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go / go / 365059e1d13c30c26ef0725becea2329f47cc16f / . / src / cmd / compile / internal / gc / ssa.go
blob: d4d23a2956edf65b92b75c3165fae4c57a965b42 [file] [log] [blame]
// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package gc
import (
"encoding/binary"
"fmt"
"html"
"os"
"sort"
"bufio"
"bytes"
"cmd/compile/internal/ssa"
"cmd/compile/internal/types"
"cmd/internal/obj"
"cmd/internal/obj/x86"
"cmd/internal/objabi"
"cmd/internal/src"
"cmd/internal/sys"
)
var ssaConfig *ssa.Config
var ssaCaches []ssa.Cache
var ssaDump string // early copy of $GOSSAFUNC; the func name to dump output for
var ssaDumpStdout bool // whether to dump to stdout
var ssaDumpCFG string // generate CFGs for these phases
const ssaDumpFile = "ssa.html"
// The max number of defers in a function using open-coded defers. We enforce this
// limit because the deferBits bitmask is currently a single byte (to minimize code size)
const maxOpenDefers = 8
// ssaDumpInlined holds all inlined functions when ssaDump contains a function name.
var ssaDumpInlined []*Node
func initssaconfig() {
types_ := ssa.NewTypes()
if thearch.SoftFloat {
softfloatInit()
}
// Generate a few pointer types that are uncommon in the frontend but common in the backend.
// Caching is disabled in the backend, so generating these here avoids allocations.
_ = types.NewPtr(types.Types[TINTER]) // *interface{}
_ = types.NewPtr(types.NewPtr(types.Types[TSTRING])) // **string
_ = types.NewPtr(types.NewPtr(types.Idealstring)) // **string
_ = types.NewPtr(types.NewSlice(types.Types[TINTER])) // *[]interface{}
_ = types.NewPtr(types.NewPtr(types.Bytetype)) // **byte
_ = types.NewPtr(types.NewSlice(types.Bytetype)) // *[]byte
_ = types.NewPtr(types.NewSlice(types.Types[TSTRING])) // *[]string
_ = types.NewPtr(types.NewSlice(types.Idealstring)) // *[]string
_ = types.NewPtr(types.NewPtr(types.NewPtr(types.Types[TUINT8]))) // ***uint8
_ = types.NewPtr(types.Types[TINT16]) // *int16
_ = types.NewPtr(types.Types[TINT64]) // *int64
_ = types.NewPtr(types.Errortype) // *error
types.NewPtrCacheEnabled = false
ssaConfig = ssa.NewConfig(thearch.LinkArch.Name, *types_, Ctxt, Debug['N'] == 0)
if thearch.LinkArch.Name == "386" {
ssaConfig.Set387(thearch.Use387)
}
ssaConfig.SoftFloat = thearch.SoftFloat
ssaConfig.Race = flag_race
ssaCaches = make([]ssa.Cache, nBackendWorkers)
// Set up some runtime functions we'll need to call.
assertE2I = sysfunc("assertE2I")
assertE2I2 = sysfunc("assertE2I2")
assertI2I = sysfunc("assertI2I")
assertI2I2 = sysfunc("assertI2I2")
deferproc = sysfunc("deferproc")
deferprocStack = sysfunc("deferprocStack")
Deferreturn = sysfunc("deferreturn")
Duffcopy = sysvar("duffcopy") // asm func with special ABI
Duffzero = sysvar("duffzero") // asm func with special ABI
gcWriteBarrier = sysvar("gcWriteBarrier") // asm func with special ABI
goschedguarded = sysfunc("goschedguarded")
growslice = sysfunc("growslice")
msanread = sysfunc("msanread")
msanwrite = sysfunc("msanwrite")
newobject = sysfunc("newobject")
newproc = sysfunc("newproc")
panicdivide = sysfunc("panicdivide")
panicdottypeE = sysfunc("panicdottypeE")
panicdottypeI = sysfunc("panicdottypeI")
panicnildottype = sysfunc("panicnildottype")
panicoverflow = sysfunc("panicoverflow")
panicshift = sysfunc("panicshift")
raceread = sysfunc("raceread")
racereadrange = sysfunc("racereadrange")
racewrite = sysfunc("racewrite")
racewriterange = sysfunc("racewriterange")
x86HasPOPCNT = sysvar("x86HasPOPCNT") // bool
x86HasSSE41 = sysvar("x86HasSSE41") // bool
x86HasFMA = sysvar("x86HasFMA") // bool
armHasVFPv4 = sysvar("armHasVFPv4") // bool
arm64HasATOMICS = sysvar("arm64HasATOMICS") // bool
typedmemclr = sysfunc("typedmemclr")
typedmemmove = sysfunc("typedmemmove")
Udiv = sysvar("udiv") // asm func with special ABI
writeBarrier = sysvar("writeBarrier") // struct { bool; ... }
zerobaseSym = sysvar("zerobase")
// asm funcs with special ABI
if thearch.LinkArch.Name == "amd64" {
GCWriteBarrierReg = map[int16]*obj.LSym{
x86.REG_AX: sysvar("gcWriteBarrier"),
x86.REG_CX: sysvar("gcWriteBarrierCX"),
x86.REG_DX: sysvar("gcWriteBarrierDX"),
x86.REG_BX: sysvar("gcWriteBarrierBX"),
x86.REG_BP: sysvar("gcWriteBarrierBP"),
x86.REG_SI: sysvar("gcWriteBarrierSI"),
x86.REG_R8: sysvar("gcWriteBarrierR8"),
x86.REG_R9: sysvar("gcWriteBarrierR9"),
}
}
if thearch.LinkArch.Family == sys.Wasm {
BoundsCheckFunc[ssa.BoundsIndex] = sysvar("goPanicIndex")
BoundsCheckFunc[ssa.BoundsIndexU] = sysvar("goPanicIndexU")
BoundsCheckFunc[ssa.BoundsSliceAlen] = sysvar("goPanicSliceAlen")
BoundsCheckFunc[ssa.BoundsSliceAlenU] = sysvar("goPanicSliceAlenU")
BoundsCheckFunc[ssa.BoundsSliceAcap] = sysvar("goPanicSliceAcap")
BoundsCheckFunc[ssa.BoundsSliceAcapU] = sysvar("goPanicSliceAcapU")
BoundsCheckFunc[ssa.BoundsSliceB] = sysvar("goPanicSliceB")
BoundsCheckFunc[ssa.BoundsSliceBU] = sysvar("goPanicSliceBU")
BoundsCheckFunc[ssa.BoundsSlice3Alen] = sysvar("goPanicSlice3Alen")
BoundsCheckFunc[ssa.BoundsSlice3AlenU] = sysvar("goPanicSlice3AlenU")
BoundsCheckFunc[ssa.BoundsSlice3Acap] = sysvar("goPanicSlice3Acap")
BoundsCheckFunc[ssa.BoundsSlice3AcapU] = sysvar("goPanicSlice3AcapU")
BoundsCheckFunc[ssa.BoundsSlice3B] = sysvar("goPanicSlice3B")
BoundsCheckFunc[ssa.BoundsSlice3BU] = sysvar("goPanicSlice3BU")
BoundsCheckFunc[ssa.BoundsSlice3C] = sysvar("goPanicSlice3C")
BoundsCheckFunc[ssa.BoundsSlice3CU] = sysvar("goPanicSlice3CU")
} else {
BoundsCheckFunc[ssa.BoundsIndex] = sysvar("panicIndex")
BoundsCheckFunc[ssa.BoundsIndexU] = sysvar("panicIndexU")
BoundsCheckFunc[ssa.BoundsSliceAlen] = sysvar("panicSliceAlen")
BoundsCheckFunc[ssa.BoundsSliceAlenU] = sysvar("panicSliceAlenU")
BoundsCheckFunc[ssa.BoundsSliceAcap] = sysvar("panicSliceAcap")
BoundsCheckFunc[ssa.BoundsSliceAcapU] = sysvar("panicSliceAcapU")
BoundsCheckFunc[ssa.BoundsSliceB] = sysvar("panicSliceB")
BoundsCheckFunc[ssa.BoundsSliceBU] = sysvar("panicSliceBU")
BoundsCheckFunc[ssa.BoundsSlice3Alen] = sysvar("panicSlice3Alen")
BoundsCheckFunc[ssa.BoundsSlice3AlenU] = sysvar("panicSlice3AlenU")
BoundsCheckFunc[ssa.BoundsSlice3Acap] = sysvar("panicSlice3Acap")
BoundsCheckFunc[ssa.BoundsSlice3AcapU] = sysvar("panicSlice3AcapU")
BoundsCheckFunc[ssa.BoundsSlice3B] = sysvar("panicSlice3B")
BoundsCheckFunc[ssa.BoundsSlice3BU] = sysvar("panicSlice3BU")
BoundsCheckFunc[ssa.BoundsSlice3C] = sysvar("panicSlice3C")
BoundsCheckFunc[ssa.BoundsSlice3CU] = sysvar("panicSlice3CU")
}
if thearch.LinkArch.PtrSize == 4 {
ExtendCheckFunc[ssa.BoundsIndex] = sysvar("panicExtendIndex")
ExtendCheckFunc[ssa.BoundsIndexU] = sysvar("panicExtendIndexU")
ExtendCheckFunc[ssa.BoundsSliceAlen] = sysvar("panicExtendSliceAlen")
ExtendCheckFunc[ssa.BoundsSliceAlenU] = sysvar("panicExtendSliceAlenU")
ExtendCheckFunc[ssa.BoundsSliceAcap] = sysvar("panicExtendSliceAcap")
ExtendCheckFunc[ssa.BoundsSliceAcapU] = sysvar("panicExtendSliceAcapU")
ExtendCheckFunc[ssa.BoundsSliceB] = sysvar("panicExtendSliceB")
ExtendCheckFunc[ssa.BoundsSliceBU] = sysvar("panicExtendSliceBU")
ExtendCheckFunc[ssa.BoundsSlice3Alen] = sysvar("panicExtendSlice3Alen")
ExtendCheckFunc[ssa.BoundsSlice3AlenU] = sysvar("panicExtendSlice3AlenU")
ExtendCheckFunc[ssa.BoundsSlice3Acap] = sysvar("panicExtendSlice3Acap")
ExtendCheckFunc[ssa.BoundsSlice3AcapU] = sysvar("panicExtendSlice3AcapU")
ExtendCheckFunc[ssa.BoundsSlice3B] = sysvar("panicExtendSlice3B")
ExtendCheckFunc[ssa.BoundsSlice3BU] = sysvar("panicExtendSlice3BU")
ExtendCheckFunc[ssa.BoundsSlice3C] = sysvar("panicExtendSlice3C")
ExtendCheckFunc[ssa.BoundsSlice3CU] = sysvar("panicExtendSlice3CU")
}
// GO386=387 runtime definitions
ControlWord64trunc = sysvar("controlWord64trunc") // uint16
ControlWord32 = sysvar("controlWord32") // uint16
// Wasm (all asm funcs with special ABIs)
WasmMove = sysvar("wasmMove")
WasmZero = sysvar("wasmZero")
WasmDiv = sysvar("wasmDiv")
WasmTruncS = sysvar("wasmTruncS")
WasmTruncU = sysvar("wasmTruncU")
SigPanic = sysfunc("sigpanic")
}
// getParam returns the Field of ith param of node n (which is a
// function/method/interface call), where the receiver of a method call is
// considered as the 0th parameter. This does not include the receiver of an
// interface call.
func getParam(n *Node, i int) *types.Field {
t := n.Left.Type
if n.Op == OCALLMETH {
if i == 0 {
return t.Recv()
}
return t.Params().Field(i - 1)
}
return t.Params().Field(i)
}
// dvarint writes a varint v to the funcdata in symbol x and returns the new offset
func dvarint(x *obj.LSym, off int, v int64) int {
if v < 0 || v > 1e9 {
panic(fmt.Sprintf("dvarint: bad offset for funcdata - %v", v))
}
if v < 1<<7 {
return duint8(x, off, uint8(v))
}
off = duint8(x, off, uint8((v&127)|128))
if v < 1<<14 {
return duint8(x, off, uint8(v>>7))
}
off = duint8(x, off, uint8(((v>>7)&127)|128))
if v < 1<<21 {
return duint8(x, off, uint8(v>>14))
}
off = duint8(x, off, uint8(((v>>14)&127)|128))
if v < 1<<28 {
return duint8(x, off, uint8(v>>21))
}
off = duint8(x, off, uint8(((v>>21)&127)|128))
return duint8(x, off, uint8(v>>28))
}
// emitOpenDeferInfo emits FUNCDATA information about the defers in a function
// that is using open-coded defers. This funcdata is used to determine the active
// defers in a function and execute those defers during panic processing.
//
// The funcdata is all encoded in varints (since values will almost always be less than
// 128, but stack offsets could potentially be up to 2Gbyte). All "locations" (offsets)
// for stack variables are specified as the number of bytes below varp (pointer to the
// top of the local variables) for their starting address. The format is:
//
// - Max total argument size among all the defers
// - Offset of the deferBits variable
// - Number of defers in the function
// - Information about each defer call, in reverse order of appearance in the function:
// - Total argument size of the call
// - Offset of the closure value to call
// - Number of arguments (including interface receiver or method receiver as first arg)
// - Information about each argument
// - Offset of the stored defer argument in this function's frame
// - Size of the argument
// - Offset of where argument should be placed in the args frame when making call
func (s *state) emitOpenDeferInfo() {
x := Ctxt.Lookup(s.curfn.Func.lsym.Name + ".opendefer")
s.curfn.Func.lsym.Func.OpenCodedDeferInfo = x
off := 0
// Compute maxargsize (max size of arguments for all defers)
// first, so we can output it first to the funcdata
var maxargsize int64
for i := len(s.openDefers) - 1; i >= 0; i-- {
r := s.openDefers[i]
argsize := r.n.Left.Type.ArgWidth()
if argsize > maxargsize {
maxargsize = argsize
}
}
off = dvarint(x, off, maxargsize)
off = dvarint(x, off, -s.deferBitsTemp.Xoffset)
off = dvarint(x, off, int64(len(s.openDefers)))
// Write in reverse-order, for ease of running in that order at runtime
for i := len(s.openDefers) - 1; i >= 0; i-- {
r := s.openDefers[i]
off = dvarint(x, off, r.n.Left.Type.ArgWidth())
off = dvarint(x, off, -r.closureNode.Xoffset)
numArgs := len(r.argNodes)
if r.rcvrNode != nil {
// If there's an interface receiver, treat/place it as the first
// arg. (If there is a method receiver, it's already included as
// first arg in r.argNodes.)
numArgs++
}
off = dvarint(x, off, int64(numArgs))
if r.rcvrNode != nil {
off = dvarint(x, off, -r.rcvrNode.Xoffset)
off = dvarint(x, off, s.config.PtrSize)
off = dvarint(x, off, 0)
}
for j, arg := range r.argNodes {
f := getParam(r.n, j)
off = dvarint(x, off, -arg.Xoffset)
off = dvarint(x, off, f.Type.Size())
off = dvarint(x, off, f.Offset)
}
}
}
// buildssa builds an SSA function for fn.
// worker indicates which of the backend workers is doing the processing.
func buildssa(fn *Node, worker int) *ssa.Func {
name := fn.funcname()
printssa := name == ssaDump
var astBuf *bytes.Buffer
if printssa {
astBuf = &bytes.Buffer{}
fdumplist(astBuf, "buildssa-enter", fn.Func.Enter)
fdumplist(astBuf, "buildssa-body", fn.Nbody)
fdumplist(astBuf, "buildssa-exit", fn.Func.Exit)
if ssaDumpStdout {
fmt.Println("generating SSA for", name)
fmt.Print(astBuf.String())
}
}
var s state
s.pushLine(fn.Pos)
defer s.popLine()
s.hasdefer = fn.Func.HasDefer()
if fn.Func.Pragma&CgoUnsafeArgs != 0 {
s.cgoUnsafeArgs = true
}
fe := ssafn{
curfn: fn,
log: printssa && ssaDumpStdout,
}
s.curfn = fn
s.f = ssa.NewFunc(&fe)
s.config = ssaConfig
s.f.Type = fn.Type
s.f.Config = ssaConfig
s.f.Cache = &ssaCaches[worker]
s.f.Cache.Reset()
s.f.DebugTest = s.f.DebugHashMatch("GOSSAHASH", name)
s.f.Name = name
s.f.PrintOrHtmlSSA = printssa
if fn.Func.Pragma&Nosplit != 0 {
s.f.NoSplit = true
}
s.panics = map[funcLine]*ssa.Block{}
s.softFloat = s.config.SoftFloat
if printssa {
s.f.HTMLWriter = ssa.NewHTMLWriter(ssaDumpFile, s.f, ssaDumpCFG)
// TODO: generate and print a mapping from nodes to values and blocks
dumpSourcesColumn(s.f.HTMLWriter, fn)
s.f.HTMLWriter.WriteAST("AST", astBuf)
}
// Allocate starting block
s.f.Entry = s.f.NewBlock(ssa.BlockPlain)
// Allocate starting values
s.labels = map[string]*ssaLabel{}
s.labeledNodes = map[*Node]*ssaLabel{}
s.fwdVars = map[*Node]*ssa.Value{}
s.startmem = s.entryNewValue0(ssa.OpInitMem, types.TypeMem)
s.hasOpenDefers = Debug['N'] == 0 && s.hasdefer && !s.curfn.Func.OpenCodedDeferDisallowed()
switch {
case s.hasOpenDefers && (Ctxt.Flag_shared || Ctxt.Flag_dynlink) && thearch.LinkArch.Name == "386":
// Don't support open-coded defers for 386 ONLY when using shared
// libraries, because there is extra code (added by rewriteToUseGot())
// preceding the deferreturn/ret code that is generated by gencallret()
// that we don't track correctly.
s.hasOpenDefers = false
}
if s.hasOpenDefers && s.curfn.Func.Exit.Len() > 0 {
// Skip doing open defers if there is any extra exit code (likely
// copying heap-allocated return values or race detection), since
// we will not generate that code in the case of the extra
// deferreturn/ret segment.
s.hasOpenDefers = false
}
if s.hasOpenDefers &&
s.curfn.Func.numReturns*s.curfn.Func.numDefers > 15 {
// Since we are generating defer calls at every exit for
// open-coded defers, skip doing open-coded defers if there are
// too many returns (especially if there are multiple defers).
// Open-coded defers are most important for improving performance
// for smaller functions (which don't have many returns).
s.hasOpenDefers = false
}
s.sp = s.entryNewValue0(ssa.OpSP, types.Types[TUINTPTR]) // TODO: use generic pointer type (unsafe.Pointer?) instead
s.sb = s.entryNewValue0(ssa.OpSB, types.Types[TUINTPTR])
s.startBlock(s.f.Entry)
s.vars[&memVar] = s.startmem
if s.hasOpenDefers {
// Create the deferBits variable and stack slot. deferBits is a
// bitmask showing which of the open-coded defers in this function
// have been activated.
deferBitsTemp := tempAt(src.NoXPos, s.curfn, types.Types[TUINT8])
s.deferBitsTemp = deferBitsTemp
// For this value, AuxInt is initialized to zero by default
startDeferBits := s.entryNewValue0(ssa.OpConst8, types.Types[TUINT8])
s.vars[&deferBitsVar] = startDeferBits
s.deferBitsAddr = s.addr(deferBitsTemp)
s.store(types.Types[TUINT8], s.deferBitsAddr, startDeferBits)
// Make sure that the deferBits stack slot is kept alive (for use
// by panics) and stores to deferBits are not eliminated, even if
// all checking code on deferBits in the function exit can be
// eliminated, because the defer statements were all
// unconditional.
s.vars[&memVar] = s.newValue1Apos(ssa.OpVarLive, types.TypeMem, deferBitsTemp, s.mem(), false)
}
// Generate addresses of local declarations
s.decladdrs = map[*Node]*ssa.Value{}
for _, n := range fn.Func.Dcl {
switch n.Class() {
case PPARAM, PPARAMOUT:
s.decladdrs[n] = s.entryNewValue2A(ssa.OpLocalAddr, types.NewPtr(n.Type), n, s.sp, s.startmem)
if n.Class() == PPARAMOUT && s.canSSA(n) {
// Save ssa-able PPARAMOUT variables so we can
// store them back to the stack at the end of
// the function.
s.returns = append(s.returns, n)
}
case PAUTO:
// processed at each use, to prevent Addr coming
// before the decl.
case PAUTOHEAP:
// moved to heap - already handled by frontend
case PFUNC:
// local function - already handled by frontend
default:
s.Fatalf("local variable with class %v unimplemented", n.Class())
}
}
// Populate SSAable arguments.
for _, n := range fn.Func.Dcl {
if n.Class() == PPARAM && s.canSSA(n) {
v := s.newValue0A(ssa.OpArg, n.Type, n)
s.vars[n] = v
s.addNamedValue(n, v) // This helps with debugging information, not needed for compilation itself.
}
}
// Convert the AST-based IR to the SSA-based IR
s.stmtList(fn.Func.Enter)
s.stmtList(fn.Nbody)
// fallthrough to exit
if s.curBlock != nil {
s.pushLine(fn.Func.Endlineno)
s.exit()
s.popLine()
}
for _, b := range s.f.Blocks {
if b.Pos != src.NoXPos {
s.updateUnsetPredPos(b)
}
}
s.insertPhis()
// Main call to ssa package to compile function
ssa.Compile(s.f)
if s.hasOpenDefers {
s.emitOpenDeferInfo()
}
return s.f
}
func dumpSourcesColumn(writer *ssa.HTMLWriter, fn *Node) {
// Read sources of target function fn.
fname := Ctxt.PosTable.Pos(fn.Pos).Filename()
targetFn, err := readFuncLines(fname, fn.Pos.Line(), fn.Func.Endlineno.Line())
if err != nil {
writer.Logf("cannot read sources for function %v: %v", fn, err)
}
// Read sources of inlined functions.
var inlFns []*ssa.FuncLines
for _, fi := range ssaDumpInlined {
var elno src.XPos
if fi.Name.Defn == nil {
// Endlineno is filled from exported data.
elno = fi.Func.Endlineno
} else {
elno = fi.Name.Defn.Func.Endlineno
}
fname := Ctxt.PosTable.Pos(fi.Pos).Filename()
fnLines, err := readFuncLines(fname, fi.Pos.Line(), elno.Line())
if err != nil {
writer.Logf("cannot read sources for inlined function %v: %v", fi, err)
continue
}
inlFns = append(inlFns, fnLines)
}
sort.Sort(ssa.ByTopo(inlFns))
if targetFn != nil {
inlFns = append([]*ssa.FuncLines{targetFn}, inlFns...)
}
writer.WriteSources("sources", inlFns)
}
func readFuncLines(file string, start, end uint) (*ssa.FuncLines, error) {
f, err := os.Open(os.ExpandEnv(file))
if err != nil {
return nil, err
}
defer f.Close()
var lines []string
ln := uint(1)
scanner := bufio.NewScanner(f)
for scanner.Scan() && ln <= end {
if ln >= start {
lines = append(lines, scanner.Text())
}
ln++
}
return &ssa.FuncLines{Filename: file, StartLineno: start, Lines: lines}, nil
}
// updateUnsetPredPos propagates the earliest-value position information for b
// towards all of b's predecessors that need a position, and recurs on that
// predecessor if its position is updated. B should have a non-empty position.
func (s *state) updateUnsetPredPos(b *ssa.Block) {
if b.Pos == src.NoXPos {
s.Fatalf("Block %s should have a position", b)
}
bestPos := src.NoXPos
for _, e := range b.Preds {
p := e.Block()
if !p.LackingPos() {
continue
}
if bestPos == src.NoXPos {
bestPos = b.Pos
for _, v := range b.Values {
if v.LackingPos() {
continue
}
if v.Pos != src.NoXPos {
// Assume values are still in roughly textual order;
// TODO: could also seek minimum position?
bestPos = v.Pos
break
}
}
}
p.Pos = bestPos
s.updateUnsetPredPos(p) // We do not expect long chains of these, thus recursion is okay.
}
}
// Information about each open-coded defer.
type openDeferInfo struct {
// The ODEFER node representing the function call of the defer
n *Node
// If defer call is closure call, the address of the argtmp where the
// closure is stored.
closure *ssa.Value
// The node representing the argtmp where the closure is stored - used for
// function, method, or interface call, to store a closure that panic
// processing can use for this defer.
closureNode *Node
// If defer call is interface call, the address of the argtmp where the
// receiver is stored
rcvr *ssa.Value
// The node representing the argtmp where the receiver is stored
rcvrNode *Node
// The addresses of the argtmps where the evaluated arguments of the defer
// function call are stored.
argVals []*ssa.Value
// The nodes representing the argtmps where the args of the defer are stored
argNodes []*Node
}
type state struct {
// configuration (arch) information
config *ssa.Config
// function we're building
f *ssa.Func
// Node for function
curfn *Node
// labels and labeled control flow nodes (OFOR, OFORUNTIL, OSWITCH, OSELECT) in f
labels map[string]*ssaLabel
labeledNodes map[*Node]*ssaLabel
// unlabeled break and continue statement tracking
breakTo *ssa.Block // current target for plain break statement
continueTo *ssa.Block // current target for plain continue statement
// current location where we're interpreting the AST
curBlock *ssa.Block
// variable assignments in the current block (map from variable symbol to ssa value)
// *Node is the unique identifier (an ONAME Node) for the variable.
// TODO: keep a single varnum map, then make all of these maps slices instead?
vars map[*Node]*ssa.Value
// fwdVars are variables that are used before they are defined in the current block.
// This map exists just to coalesce multiple references into a single FwdRef op.
// *Node is the unique identifier (an ONAME Node) for the variable.
fwdVars map[*Node]*ssa.Value
// all defined variables at the end of each block. Indexed by block ID.
defvars []map[*Node]*ssa.Value
// addresses of PPARAM and PPARAMOUT variables.
decladdrs map[*Node]*ssa.Value
// starting values. Memory, stack pointer, and globals pointer
startmem *ssa.Value
sp *ssa.Value
sb *ssa.Value
// value representing address of where deferBits autotmp is stored
deferBitsAddr *ssa.Value
deferBitsTemp *Node
// line number stack. The current line number is top of stack
line []src.XPos
// the last line number processed; it may have been popped
lastPos src.XPos
// list of panic calls by function name and line number.
// Used to deduplicate panic calls.
panics map[funcLine]*ssa.Block
// list of PPARAMOUT (return) variables.
returns []*Node
cgoUnsafeArgs bool
hasdefer bool // whether the function contains a defer statement
softFloat bool
hasOpenDefers bool // whether we are doing open-coded defers
// If doing open-coded defers, list of info about the defer calls in
// scanning order. Hence, at exit we should run these defers in reverse
// order of this list
openDefers []*openDeferInfo
// For open-coded defers, this is the beginning and end blocks of the last
// defer exit code that we have generated so far. We use these to share
// code between exits if the shareDeferExits option (disabled by default)
// is on.
lastDeferExit *ssa.Block // Entry block of last defer exit code we generated
lastDeferFinalBlock *ssa.Block // Final block of last defer exit code we generated
lastDeferCount int // Number of defers encountered at that point
}
type funcLine struct {
f *obj.LSym
base *src.PosBase
line uint
}
type ssaLabel struct {
target *ssa.Block // block identified by this label
breakTarget *ssa.Block // block to break to in control flow node identified by this label
continueTarget *ssa.Block // block to continue to in control flow node identified by this label
}
// label returns the label associated with sym, creating it if necessary.
func (s *state) label(sym *types.Sym) *ssaLabel {
lab := s.labels[sym.Name]
if lab == nil {
lab = new(ssaLabel)
s.labels[sym.Name] = lab
}
return lab
}
func (s *state) Logf(msg string, args ...interface{}) { s.f.Logf(msg, args...) }
func (s *state) Log() bool { return s.f.Log() }
func (s *state) Fatalf(msg string, args ...interface{}) {
s.f.Frontend().Fatalf(s.peekPos(), msg, args...)
}
func (s *state) Warnl(pos src.XPos, msg string, args ...interface{}) { s.f.Warnl(pos, msg, args...) }
func (s *state) Debug_checknil() bool { return s.f.Frontend().Debug_checknil() }
var (
// dummy node for the memory variable
memVar = Node{Op: ONAME, Sym: &types.Sym{Name: "mem"}}
// dummy nodes for temporary variables
ptrVar = Node{Op: ONAME, Sym: &types.Sym{Name: "ptr"}}
lenVar = Node{Op: ONAME, Sym: &types.Sym{Name: "len"}}
newlenVar = Node{Op: ONAME, Sym: &types.Sym{Name: "newlen"}}
capVar = Node{Op: ONAME, Sym: &types.Sym{Name: "cap"}}
typVar = Node{Op: ONAME, Sym: &types.Sym{Name: "typ"}}
okVar = Node{Op: ONAME, Sym: &types.Sym{Name: "ok"}}
deferBitsVar = Node{Op: ONAME, Sym: &types.Sym{Name: "deferBits"}}
)
// startBlock sets the current block we're generating code in to b.
func (s *state) startBlock(b *ssa.Block) {
if s.curBlock != nil {
s.Fatalf("starting block %v when block %v has not ended", b, s.curBlock)
}
s.curBlock = b
s.vars = map[*Node]*ssa.Value{}
for n := range s.fwdVars {
delete(s.fwdVars, n)
}
}
// endBlock marks the end of generating code for the current block.
// Returns the (former) current block. Returns nil if there is no current
// block, i.e. if no code flows to the current execution point.
func (s *state) endBlock() *ssa.Block {
b := s.curBlock
if b == nil {
return nil
}
for len(s.defvars) <= int(b.ID) {
s.defvars = append(s.defvars, nil)
}
s.defvars[b.ID] = s.vars
s.curBlock = nil
s.vars = nil
if b.LackingPos() {
// Empty plain blocks get the line of their successor (handled after all blocks created),
// except for increment blocks in For statements (handled in ssa conversion of OFOR),
// and for blocks ending in GOTO/BREAK/CONTINUE.
b.Pos = src.NoXPos
} else {
b.Pos = s.lastPos
}
return b
}
// pushLine pushes a line number on the line number stack.
func (s *state) pushLine(line src.XPos) {
if !line.IsKnown() {
// the frontend may emit node with line number missing,
// use the parent line number in this case.
line = s.peekPos()
if Debug['K'] != 0 {
Warn("buildssa: unknown position (line 0)")
}
} else {
s.lastPos = line
}
s.line = append(s.line, line)
}
// popLine pops the top of the line number stack.
func (s *state) popLine() {
s.line = s.line[:len(s.line)-1]
}
// peekPos peeks the top of the line number stack.
func (s *state) peekPos() src.XPos {
return s.line[len(s.line)-1]
}
// newValue0 adds a new value with no arguments to the current block.
func (s *state) newValue0(op ssa.Op, t *types.Type) *ssa.Value {
return s.curBlock.NewValue0(s.peekPos(), op, t)
}
// newValue0A adds a new value with no arguments and an aux value to the current block.
func (s *state) newValue0A(op ssa.Op, t *types.Type, aux interface{}) *ssa.Value {
return s.curBlock.NewValue0A(s.peekPos(), op, t, aux)
}
// newValue0I adds a new value with no arguments and an auxint value to the current block.
func (s *state) newValue0I(op ssa.Op, t *types.Type, auxint int64) *ssa.Value {
return s.curBlock.NewValue0I(s.peekPos(), op, t, auxint)
}
// newValue1 adds a new value with one argument to the current block.
func (s *state) newValue1(op ssa.Op, t *types.Type, arg *ssa.Value) *ssa.Value {
return s.curBlock.NewValue1(s.peekPos(), op, t, arg)
}
// newValue1A adds a new value with one argument and an aux value to the current block.
func (s *state) newValue1A(op ssa.Op, t *types.Type, aux interface{}, arg *ssa.Value) *ssa.Value {
return s.curBlock.NewValue1A(s.peekPos(), op, t, aux, arg)
}
// newValue1Apos adds a new value with one argument and an aux value to the current block.
// isStmt determines whether the created values may be a statement or not
// (i.e., false means never, yes means maybe).
func (s *state) newValue1Apos(op ssa.Op, t *types.Type, aux interface{}, arg *ssa.Value, isStmt bool) *ssa.Value {
if isStmt {
return s.curBlock.NewValue1A(s.peekPos(), op, t, aux, arg)
}
return s.curBlock.NewValue1A(s.peekPos().WithNotStmt(), op, t, aux, arg)
}
// newValue1I adds a new value with one argument and an auxint value to the current block.
func (s *state) newValue1I(op ssa.Op, t *types.Type, aux int64, arg *ssa.Value) *ssa.Value {
return s.curBlock.NewValue1I(s.peekPos(), op, t, aux, arg)
}
// newValue2 adds a new value with two arguments to the current block.
func (s *state) newValue2(op ssa.Op, t *types.Type, arg0, arg1 *ssa.Value) *ssa.Value {
return s.curBlock.NewValue2(s.peekPos(), op, t, arg0, arg1)
}
// newValue2Apos adds a new value with two arguments and an aux value to the current block.
// isStmt determines whether the created values may be a statement or not
// (i.e., false means never, yes means maybe).
func (s *state) newValue2Apos(op ssa.Op, t *types.Type, aux interface{}, arg0, arg1 *ssa.Value, isStmt bool) *ssa.Value {
if isStmt {
return s.curBlock.NewValue2A(s.peekPos(), op, t, aux, arg0, arg1)
}
return s.curBlock.NewValue2A(s.peekPos().WithNotStmt(), op, t, aux, arg0, arg1)
}
// newValue2I adds a new value with two arguments and an auxint value to the current block.
func (s *state) newValue2I(op ssa.Op, t *types.Type, aux int64, arg0, arg1 *ssa.Value) *ssa.Value {
return s.curBlock.NewValue2I(s.peekPos(), op, t, aux, arg0, arg1)
}
// newValue3 adds a new value with three arguments to the current block.
func (s *state) newValue3(op ssa.Op, t *types.Type, arg0, arg1, arg2 *ssa.Value) *ssa.Value {
return s.curBlock.NewValue3(s.peekPos(), op, t, arg0, arg1, arg2)
}
// newValue3I adds a new value with three arguments and an auxint value to the current block.
func (s *state) newValue3I(op ssa.Op, t *types.Type, aux int64, arg0, arg1, arg2 *ssa.Value) *ssa.Value {
return s.curBlock.NewValue3I(s.peekPos(), op, t, aux, arg0, arg1, arg2)
}
// newValue3A adds a new value with three arguments and an aux value to the current block.
func (s *state) newValue3A(op ssa.Op, t *types.Type, aux interface{}, arg0, arg1, arg2 *ssa.Value) *ssa.Value {
return s.curBlock.NewValue3A(s.peekPos(), op, t, aux, arg0, arg1, arg2)
}
// newValue3Apos adds a new value with three arguments and an aux value to the current block.
// isStmt determines whether the created values may be a statement or not
// (i.e., false means never, yes means maybe).
func (s *state) newValue3Apos(op ssa.Op, t *types.Type, aux interface{}, arg0, arg1, arg2 *ssa.Value, isStmt bool) *ssa.Value {
if isStmt {
return s.curBlock.NewValue3A(s.peekPos(), op, t, aux, arg0, arg1, arg2)
}
return s.curBlock.NewValue3A(s.peekPos().WithNotStmt(), op, t, aux, arg0, arg1, arg2)
}
// newValue4 adds a new value with four arguments to the current block.
func (s *state) newValue4(op ssa.Op, t *types.Type, arg0, arg1, arg2, arg3 *ssa.Value) *ssa.Value {
return s.curBlock.NewValue4(s.peekPos(), op, t, arg0, arg1, arg2, arg3)
}
// newValue4 adds a new value with four arguments and an auxint value to the current block.
func (s *state) newValue4I(op ssa.Op, t *types.Type, aux int64, arg0, arg1, arg2, arg3 *ssa.Value) *ssa.Value {
return s.curBlock.NewValue4I(s.peekPos(), op, t, aux, arg0, arg1, arg2, arg3)
}
// entryNewValue0 adds a new value with no arguments to the entry block.
func (s *state) entryNewValue0(op ssa.Op, t *types.Type) *ssa.Value {
return s.f.Entry.NewValue0(src.NoXPos, op, t)
}
// entryNewValue0A adds a new value with no arguments and an aux value to the entry block.
func (s *state) entryNewValue0A(op ssa.Op, t *types.Type, aux interface{}) *ssa.Value {
return s.f.Entry.NewValue0A(src.NoXPos, op, t, aux)
}
// entryNewValue1 adds a new value with one argument to the entry block.
func (s *state) entryNewValue1(op ssa.Op, t *types.Type, arg *ssa.Value) *ssa.Value {
return s.f.Entry.NewValue1(src.NoXPos, op, t, arg)
}
// entryNewValue1 adds a new value with one argument and an auxint value to the entry block.
func (s *state) entryNewValue1I(op ssa.Op, t *types.Type, auxint int64, arg *ssa.Value) *ssa.Value {
return s.f.Entry.NewValue1I(src.NoXPos, op, t, auxint, arg)
}
// entryNewValue1A adds a new value with one argument and an aux value to the entry block.
func (s *state) entryNewValue1A(op ssa.Op, t *types.Type, aux interface{}, arg *ssa.Value) *ssa.Value {
return s.f.Entry.NewValue1A(src.NoXPos, op, t, aux, arg)
}
// entryNewValue2 adds a new value with two arguments to the entry block.
func (s *state) entryNewValue2(op ssa.Op, t *types.Type, arg0, arg1 *ssa.Value) *ssa.Value {
return s.f.Entry.NewValue2(src.NoXPos, op, t, arg0, arg1)
}
// entryNewValue2A adds a new value with two arguments and an aux value to the entry block.
func (s *state) entryNewValue2A(op ssa.Op, t *types.Type, aux interface{}, arg0, arg1 *ssa.Value) *ssa.Value {
return s.f.Entry.NewValue2A(src.NoXPos, op, t, aux, arg0, arg1)
}
// const* routines add a new const value to the entry block.
func (s *state) constSlice(t *types.Type) *ssa.Value {
return s.f.ConstSlice(t)
}
func (s *state) constInterface(t *types.Type) *ssa.Value {
return s.f.ConstInterface(t)
}
func (s *state) constNil(t *types.Type) *ssa.Value { return s.f.ConstNil(t) }
func (s *state) constEmptyString(t *types.Type) *ssa.Value {
return s.f.ConstEmptyString(t)
}
func (s *state) constBool(c bool) *ssa.Value {
return s.f.ConstBool(types.Types[TBOOL], c)
}
func (s *state) constInt8(t *types.Type, c int8) *ssa.Value {
return s.f.ConstInt8(t, c)
}
func (s *state) constInt16(t *types.Type, c int16) *ssa.Value {
return s.f.ConstInt16(t, c)
}
func (s *state) constInt32(t *types.Type, c int32) *ssa.Value {
return s.f.ConstInt32(t, c)
}
func (s *state) constInt64(t *types.Type, c int64) *ssa.Value {
return s.f.ConstInt64(t, c)
}
func (s *state) constFloat32(t *types.Type, c float64) *ssa.Value {
return s.f.ConstFloat32(t, c)
}
func (s *state) constFloat64(t *types.Type, c float64) *ssa.Value {
return s.f.ConstFloat64(t, c)
}
func (s *state) constInt(t *types.Type, c int64) *ssa.Value {
if s.config.PtrSize == 8 {
return s.constInt64(t, c)
}
if int64(int32(c)) != c {
s.Fatalf("integer constant too big %d", c)
}
return s.constInt32(t, int32(c))
}
func (s *state) constOffPtrSP(t *types.Type, c int64) *ssa.Value {
return s.f.ConstOffPtrSP(t, c, s.sp)
}
// newValueOrSfCall* are wrappers around newValue*, which may create a call to a
// soft-float runtime function instead (when emitting soft-float code).
func (s *state) newValueOrSfCall1(op ssa.Op, t *types.Type, arg *ssa.Value) *ssa.Value {
if s.softFloat {
if c, ok := s.sfcall(op, arg); ok {
return c
}
}
return s.newValue1(op, t, arg)
}
func (s *state) newValueOrSfCall2(op ssa.Op, t *types.Type, arg0, arg1 *ssa.Value) *ssa.Value {
if s.softFloat {
if c, ok := s.sfcall(op, arg0, arg1); ok {
return c
}
}
return s.newValue2(op, t, arg0, arg1)
}
func (s *state) instrument(t *types.Type, addr *ssa.Value, wr bool) {
if !s.curfn.Func.InstrumentBody() {
return
}
w := t.Size()
if w == 0 {
return // can't race on zero-sized things
}
if ssa.IsSanitizerSafeAddr(addr) {
return
}
var fn *obj.LSym
needWidth := false
if flag_msan {
fn = msanread
if wr {
fn = msanwrite
}
needWidth = true
} else if flag_race && t.NumComponents(types.CountBlankFields) > 1 {
// for composite objects we have to write every address
// because a write might happen to any subobject.
// composites with only one element don't have subobjects, though.
fn = racereadrange
if wr {
fn = racewriterange
}
needWidth = true
} else if flag_race {
// for non-composite objects we can write just the start
// address, as any write must write the first byte.
fn = raceread
if wr {
fn = racewrite
}
} else {
panic("unreachable")
}
args := []*ssa.Value{addr}
if needWidth {
args = append(args, s.constInt(types.Types[TUINTPTR], w))
}
s.rtcall(fn, true, nil, args...)
}
func (s *state) load(t *types.Type, src *ssa.Value) *ssa.Value {
s.instrument(t, src, false)
return s.rawLoad(t, src)
}
func (s *state) rawLoad(t *types.Type, src *ssa.Value) *ssa.Value {
return s.newValue2(ssa.OpLoad, t, src, s.mem())
}
func (s *state) store(t *types.Type, dst, val *ssa.Value) {
s.vars[&memVar] = s.newValue3A(ssa.OpStore, types.TypeMem, t, dst, val, s.mem())
}
func (s *state) zero(t *types.Type, dst *ssa.Value) {
s.instrument(t, dst, true)
store := s.newValue2I(ssa.OpZero, types.TypeMem, t.Size(), dst, s.mem())
store.Aux = t
s.vars[&memVar] = store
}
func (s *state) move(t *types.Type, dst, src *ssa.Value) {
s.instrument(t, src, false)
s.instrument(t, dst, true)
store := s.newValue3I(ssa.OpMove, types.TypeMem, t.Size(), dst, src, s.mem())
store.Aux = t
s.vars[&memVar] = store
}
// stmtList converts the statement list n to SSA and adds it to s.
func (s *state) stmtList(l Nodes) {
for _, n := range l.Slice() {
s.stmt(n)
}
}
// stmt converts the statement n to SSA and adds it to s.
func (s *state) stmt(n *Node) {
if !(n.Op == OVARKILL || n.Op == OVARLIVE || n.Op == OVARDEF) {
// OVARKILL, OVARLIVE, and OVARDEF are invisible to the programmer, so we don't use their line numbers to avoid confusion in debugging.
s.pushLine(n.Pos)
defer s.popLine()
}
// If s.curBlock is nil, and n isn't a label (which might have an associated goto somewhere),
// then this code is dead. Stop here.
if s.curBlock == nil && n.Op != OLABEL {
return
}
s.stmtList(n.Ninit)
switch n.Op {
case OBLOCK:
s.stmtList(n.List)
// No-ops
case OEMPTY, ODCLCONST, ODCLTYPE, OFALL:
// Expression statements
case OCALLFUNC:
if isIntrinsicCall(n) {
s.intrinsicCall(n)
return
}
fallthrough
case OCALLMETH, OCALLINTER:
s.call(n, callNormal)
if n.Op == OCALLFUNC && n.Left.Op == ONAME && n.Left.Class() == PFUNC {
if fn := n.Left.Sym.Name; compiling_runtime && fn == "throw" ||
n.Left.Sym.Pkg == Runtimepkg && (fn == "throwinit" || fn == "gopanic" || fn == "panicwrap" || fn == "block" || fn == "panicmakeslicelen" || fn == "panicmakeslicecap") {
m := s.mem()
b := s.endBlock()
b.Kind = ssa.BlockExit
b.SetControl(m)
// TODO: never rewrite OPANIC to OCALLFUNC in the
// first place. Need to wait until all backends
// go through SSA.
}
}
case ODEFER:
if Debug_defer > 0 {
var defertype string
if s.hasOpenDefers {
defertype = "open-coded"
} else if n.Esc == EscNever {
defertype = "stack-allocated"
} else {
defertype = "heap-allocated"
}
Warnl(n.Pos, "%s defer", defertype)
}
if s.hasOpenDefers {
s.openDeferRecord(n.Left)
} else {
d := callDefer
if n.Esc == EscNever {
d = callDeferStack
}
s.call(n.Left, d)
}
case OGO:
s.call(n.Left, callGo)
case OAS2DOTTYPE:
res, resok := s.dottype(n.Right, true)
deref := false
if !canSSAType(n.Right.Type) {
if res.Op != ssa.OpLoad {
s.Fatalf("dottype of non-load")
}
mem := s.mem()
if mem.Op == ssa.OpVarKill {
mem = mem.Args[0]
}
if res.Args[1] != mem {
s.Fatalf("memory no longer live from 2-result dottype load")
}
deref = true
res = res.Args[0]
}
s.assign(n.List.First(), res, deref, 0)
s.assign(n.List.Second(), resok, false, 0)
return
case OAS2FUNC:
// We come here only when it is an intrinsic call returning two values.
if !isIntrinsicCall(n.Right) {
s.Fatalf("non-intrinsic AS2FUNC not expanded %v", n.Right)
}
v := s.intrinsicCall(n.Right)
v1 := s.newValue1(ssa.OpSelect0, n.List.First().Type, v)
v2 := s.newValue1(ssa.OpSelect1, n.List.Second().Type, v)
s.assign(n.List.First(), v1, false, 0)
s.assign(n.List.Second(), v2, false, 0)
return
case ODCL:
if n.Left.Class() == PAUTOHEAP {
s.Fatalf("DCL %v", n)
}
case OLABEL:
sym := n.Sym
lab := s.label(sym)
// Associate label with its control flow node, if any
if ctl := n.labeledControl(); ctl != nil {
s.labeledNodes[ctl] = lab
}
// The label might already have a target block via a goto.
if lab.target == nil {
lab.target = s.f.NewBlock(ssa.BlockPlain)
}
// Go to that label.
// (We pretend "label:" is preceded by "goto label", unless the predecessor is unreachable.)
if s.curBlock != nil {
b := s.endBlock()
b.AddEdgeTo(lab.target)
}
s.startBlock(lab.target)
case OGOTO:
sym := n.Sym
lab := s.label(sym)
if lab.target == nil {
lab.target = s.f.NewBlock(ssa.BlockPlain)
}
b := s.endBlock()
b.Pos = s.lastPos.WithIsStmt() // Do this even if b is an empty block.
b.AddEdgeTo(lab.target)
case OAS:
if n.Left == n.Right && n.Left.Op == ONAME {
// An x=x assignment. No point in doing anything
// here. In addition, skipping this assignment
// prevents generating:
// VARDEF x
// COPY x -> x
// which is bad because x is incorrectly considered
// dead before the vardef. See issue #14904.
return
}
// Evaluate RHS.
rhs := n.Right
if rhs != nil {
switch rhs.Op {
case OSTRUCTLIT, OARRAYLIT, OSLICELIT:
// All literals with nonzero fields have already been
// rewritten during walk. Any that remain are just T{}
// or equivalents. Use the zero value.
if !isZero(rhs) {
s.Fatalf("literal with nonzero value in SSA: %v", rhs)
}
rhs = nil
case OAPPEND:
// Check whether we're writing the result of an append back to the same slice.
// If so, we handle it specially to avoid write barriers on the fast
// (non-growth) path.
if !samesafeexpr(n.Left, rhs.List.First()) || Debug['N'] != 0 {
break
}
// If the slice can be SSA'd, it'll be on the stack,
// so there will be no write barriers,
// so there's no need to attempt to prevent them.
if s.canSSA(n.Left) {
if Debug_append > 0 { // replicating old diagnostic message
Warnl(n.Pos, "append: len-only update (in local slice)")
}
break
}
if Debug_append > 0 {
Warnl(n.Pos, "append: len-only update")
}
s.append(rhs, true)
return
}
}
if n.Left.isBlank() {
// _ = rhs
// Just evaluate rhs for side-effects.
if rhs != nil {
s.expr(rhs)
}
return
}
var t *types.Type
if n.Right != nil {
t = n.Right.Type
} else {
t = n.Left.Type
}
var r *ssa.Value
deref := !canSSAType(t)
if deref {
if rhs == nil {
r = nil // Signal assign to use OpZero.
} else {
r = s.addr(rhs)
}
} else {
if rhs == nil {
r = s.zeroVal(t)
} else {
r = s.expr(rhs)
}
}
var skip skipMask
if rhs != nil && (rhs.Op == OSLICE || rhs.Op == OSLICE3 || rhs.Op == OSLICESTR) && samesafeexpr(rhs.Left, n.Left) {
// We're assigning a slicing operation back to its source.
// Don't write back fields we aren't changing. See issue #14855.
i, j, k := rhs.SliceBounds()
if i != nil && (i.Op == OLITERAL && i.Val().Ctype() == CTINT && i.Int64() == 0) {
// [0:...] is the same as [:...]
i = nil
}
// TODO: detect defaults for len/cap also.
// Currently doesn't really work because (*p)[:len(*p)] appears here as:
// tmp = len(*p)
// (*p)[:tmp]
//if j != nil && (j.Op == OLEN && samesafeexpr(j.Left, n.Left)) {
// j = nil
//}
//if k != nil && (k.Op == OCAP && samesafeexpr(k.Left, n.Left)) {
// k = nil
//}
if i == nil {
skip |= skipPtr
if j == nil {
skip |= skipLen
}
if k == nil {
skip |= skipCap
}
}
}
s.assign(n.Left, r, deref, skip)
case OIF:
if Isconst(n.Left, CTBOOL) {
s.stmtList(n.Left.Ninit)
if n.Left.Bool() {
s.stmtList(n.Nbody)
} else {
s.stmtList(n.Rlist)
}
break
}
bEnd := s.f.NewBlock(ssa.BlockPlain)
var likely int8
if n.Likely() {
likely = 1
}
var bThen *ssa.Block
if n.Nbody.Len() != 0 {
bThen = s.f.NewBlock(ssa.BlockPlain)
} else {
bThen = bEnd
}
var bElse *ssa.Block
if n.Rlist.Len() != 0 {
bElse = s.f.NewBlock(ssa.BlockPlain)
} else {
bElse = bEnd
}
s.condBranch(n.Left, bThen, bElse, likely)
if n.Nbody.Len() != 0 {
s.startBlock(bThen)
s.stmtList(n.Nbody)
if b := s.endBlock(); b != nil {
b.AddEdgeTo(bEnd)
}
}
if n.Rlist.Len() != 0 {
s.startBlock(bElse)
s.stmtList(n.Rlist)
if b := s.endBlock(); b != nil {
b.AddEdgeTo(bEnd)
}
}
s.startBlock(bEnd)
case ORETURN:
s.stmtList(n.List)
b := s.exit()
b.Pos = s.lastPos.WithIsStmt()
case ORETJMP:
s.stmtList(n.List)
b := s.exit()
b.Kind = ssa.BlockRetJmp // override BlockRet
b.Aux = n.Sym.Linksym()
case OCONTINUE, OBREAK:
var to *ssa.Block
if n.Sym == nil {
// plain break/continue
switch n.Op {
case OCONTINUE:
to = s.continueTo
case OBREAK:
to = s.breakTo
}
} else {
// labeled break/continue; look up the target
sym := n.Sym
lab := s.label(sym)
switch n.Op {
case OCONTINUE:
to = lab.continueTarget
case OBREAK:
to = lab.breakTarget
}
}
b := s.endBlock()
b.Pos = s.lastPos.WithIsStmt() // Do this even if b is an empty block.
b.AddEdgeTo(to)
case OFOR, OFORUNTIL:
// OFOR: for Ninit; Left; Right { Nbody }
// cond (Left); body (Nbody); incr (Right)
//
// OFORUNTIL: for Ninit; Left; Right; List { Nbody }
// => body: { Nbody }; incr: Right; if Left { lateincr: List; goto body }; end:
bCond := s.f.NewBlock(ssa.BlockPlain)
bBody := s.f.NewBlock(ssa.BlockPlain)
bIncr := s.f.NewBlock(ssa.BlockPlain)
bEnd := s.f.NewBlock(ssa.BlockPlain)
// ensure empty for loops have correct position; issue #30167
bBody.Pos = n.Pos
// first, jump to condition test (OFOR) or body (OFORUNTIL)
b := s.endBlock()
if n.Op == OFOR {
b.AddEdgeTo(bCond)
// generate code to test condition
s.startBlock(bCond)
if n.Left != nil {
s.condBranch(n.Left, bBody, bEnd, 1)
} else {
b := s.endBlock()
b.Kind = ssa.BlockPlain
b.AddEdgeTo(bBody)
}
} else {
b.AddEdgeTo(bBody)
}
// set up for continue/break in body
prevContinue := s.continueTo
prevBreak := s.breakTo
s.continueTo = bIncr
s.breakTo = bEnd
lab := s.labeledNodes[n]
if lab != nil {
// labeled for loop
lab.continueTarget = bIncr
lab.breakTarget = bEnd
}
// generate body
s.startBlock(bBody)
s.stmtList(n.Nbody)
// tear down continue/break
s.continueTo = prevContinue
s.breakTo = prevBreak
if lab != nil {
lab.continueTarget = nil
lab.breakTarget = nil
}
// done with body, goto incr
if b := s.endBlock(); b != nil {
b.AddEdgeTo(bIncr)
}
// generate incr (and, for OFORUNTIL, condition)
s.startBlock(bIncr)
if n.Right != nil {
s.stmt(n.Right)
}
if n.Op == OFOR {
if b := s.endBlock(); b != nil {
b.AddEdgeTo(bCond)
// It can happen that bIncr ends in a block containing only VARKILL,
// and that muddles the debugging experience.
if n.Op != OFORUNTIL && b.Pos == src.NoXPos {
b.Pos = bCond.Pos
}
}
} else {
// bCond is unused in OFORUNTIL, so repurpose it.
bLateIncr := bCond
// test condition
s.condBranch(n.Left, bLateIncr, bEnd, 1)
// generate late increment
s.startBlock(bLateIncr)
s.stmtList(n.List)
s.endBlock().AddEdgeTo(bBody)
}
s.startBlock(bEnd)
case OSWITCH, OSELECT:
// These have been mostly rewritten by the front end into their Nbody fields.
// Our main task is to correctly hook up any break statements.
bEnd := s.f.NewBlock(ssa.BlockPlain)
prevBreak := s.breakTo
s.breakTo = bEnd
lab := s.labeledNodes[n]
if lab != nil {
// labeled
lab.breakTarget = bEnd
}
// generate body code
s.stmtList(n.Nbody)
s.breakTo = prevBreak
if lab != nil {
lab.breakTarget = nil
}
// walk adds explicit OBREAK nodes to the end of all reachable code paths.
// If we still have a current block here, then mark it unreachable.
if s.curBlock != nil {
m := s.mem()
b := s.endBlock()
b.Kind = ssa.BlockExit
b.SetControl(m)
}
s.startBlock(bEnd)
case OVARDEF:
if !s.canSSA(n.Left) {
s.vars[&memVar] = s.newValue1Apos(ssa.OpVarDef, types.TypeMem, n.Left, s.mem(), false)
}
case OVARKILL:
// Insert a varkill op to record that a variable is no longer live.
// We only care about liveness info at call sites, so putting the
// varkill in the store chain is enough to keep it correctly ordered
// with respect to call ops.
if !s.canSSA(n.Left) {
s.vars[&memVar] = s.newValue1Apos(ssa.OpVarKill, types.TypeMem, n.Left, s.mem(), false)
}
case OVARLIVE:
// Insert a varlive op to record that a variable is still live.
if !n.Left.Name.Addrtaken() {
s.Fatalf("VARLIVE variable %v must have Addrtaken set", n.Left)
}
switch n.Left.Class() {
case PAUTO, PPARAM, PPARAMOUT:
default:
s.Fatalf("VARLIVE variable %v must be Auto or Arg", n.Left)
}
s.vars[&memVar] = s.newValue1A(ssa.OpVarLive, types.TypeMem, n.Left, s.mem())
case OCHECKNIL:
p := s.expr(n.Left)
s.nilCheck(p)
case OINLMARK:
s.newValue1I(ssa.OpInlMark, types.TypeVoid, n.Xoffset, s.mem())
default:
s.Fatalf("unhandled stmt %v", n.Op)
}
}
// If true, share as many open-coded defer exits as possible (with the downside of
// worse line-number information)
const shareDeferExits = false
// exit processes any code that needs to be generated just before returning.
// It returns a BlockRet block that ends the control flow. Its control value
// will be set to the final memory state.
func (s *state) exit() *ssa.Block {
if s.hasdefer {
if s.hasOpenDefers {
if shareDeferExits && s.lastDeferExit != nil && len(s.openDefers) == s.lastDeferCount {
if s.curBlock.Kind != ssa.BlockPlain {
panic("Block for an exit should be BlockPlain")
}
s.curBlock.AddEdgeTo(s.lastDeferExit)
s.endBlock()
return s.lastDeferFinalBlock
}
s.openDeferExit()
} else {
s.rtcall(Deferreturn, true, nil)
}
}
// Run exit code. Typically, this code copies heap-allocated PPARAMOUT
// variables back to the stack.
s.stmtList(s.curfn.Func.Exit)
// Store SSAable PPARAMOUT variables back to stack locations.
for _, n := range s.returns {
addr := s.decladdrs[n]
val := s.variable(n, n.Type)
s.vars[&memVar] = s.newValue1A(ssa.OpVarDef, types.TypeMem, n, s.mem())
s.store(n.Type, addr, val)
// TODO: if val is ever spilled, we'd like to use the
// PPARAMOUT slot for spilling it. That won't happen
// currently.
}
// Do actual return.
m := s.mem()
b := s.endBlock()
b.Kind = ssa.BlockRet
b.SetControl(m)
if s.hasdefer && s.hasOpenDefers {
s.lastDeferFinalBlock = b
}
return b
}
type opAndType struct {
op Op
etype types.EType
}
var opToSSA = map[opAndType]ssa.Op{
opAndType{OADD, TINT8}: ssa.OpAdd8,
opAndType{OADD, TUINT8}: ssa.OpAdd8,
opAndType{OADD, TINT16}: ssa.OpAdd16,
opAndType{OADD, TUINT16}: ssa.OpAdd16,
opAndType{OADD, TINT32}: ssa.OpAdd32,
opAndType{OADD, TUINT32}: ssa.OpAdd32,
opAndType{OADD, TINT64}: ssa.OpAdd64,
opAndType{OADD, TUINT64}: ssa.OpAdd64,
opAndType{OADD, TFLOAT32}: ssa.OpAdd32F,
opAndType{OADD, TFLOAT64}: ssa.OpAdd64F,
opAndType{OSUB, TINT8}: ssa.OpSub8,
opAndType{OSUB, TUINT8}: ssa.OpSub8,
opAndType{OSUB, TINT16}: ssa.OpSub16,
opAndType{OSUB, TUINT16}: ssa.OpSub16,
opAndType{OSUB, TINT32}: ssa.OpSub32,
opAndType{OSUB, TUINT32}: ssa.OpSub32,
opAndType{OSUB, TINT64}: ssa.OpSub64,
opAndType{OSUB, TUINT64}: ssa.OpSub64,
opAndType{OSUB, TFLOAT32}: ssa.OpSub32F,
opAndType{OSUB, TFLOAT64}: ssa.OpSub64F,
opAndType{ONOT, TBOOL}: ssa.OpNot,
opAndType{ONEG, TINT8}: ssa.OpNeg8,
opAndType{ONEG, TUINT8}: ssa.OpNeg8,
opAndType{ONEG, TINT16}: ssa.OpNeg16,
opAndType{ONEG, TUINT16}: ssa.OpNeg16,
opAndType{ONEG, TINT32}: ssa.OpNeg32,
opAndType{ONEG, TUINT32}: ssa.OpNeg32,
opAndType{ONEG, TINT64}: ssa.OpNeg64,
opAndType{ONEG, TUINT64}: ssa.OpNeg64,
opAndType{ONEG, TFLOAT32}: ssa.OpNeg32F,
opAndType{ONEG, TFLOAT64}: ssa.OpNeg64F,
opAndType{OBITNOT, TINT8}: ssa.OpCom8,
opAndType{OBITNOT, TUINT8}: ssa.OpCom8,
opAndType{OBITNOT, TINT16}: ssa.OpCom16,
opAndType{OBITNOT, TUINT16}: ssa.OpCom16,
opAndType{OBITNOT, TINT32}: ssa.OpCom32,
opAndType{OBITNOT, TUINT32}: ssa.OpCom32,
opAndType{OBITNOT, TINT64}: ssa.OpCom64,
opAndType{OBITNOT, TUINT64}: ssa.OpCom64,
opAndType{OIMAG, TCOMPLEX64}: ssa.OpComplexImag,
opAndType{OIMAG, TCOMPLEX128}: ssa.OpComplexImag,
opAndType{OREAL, TCOMPLEX64}: ssa.OpComplexReal,
opAndType{OREAL, TCOMPLEX128}: ssa.OpComplexReal,
opAndType{OMUL, TINT8}: ssa.OpMul8,
opAndType{OMUL, TUINT8}: ssa.OpMul8,
opAndType{OMUL, TINT16}: ssa.OpMul16,
opAndType{OMUL, TUINT16}: ssa.OpMul16,
opAndType{OMUL, TINT32}: ssa.OpMul32,
opAndType{OMUL, TUINT32}: ssa.OpMul32,
opAndType{OMUL, TINT64}: ssa.OpMul64,
opAndType{OMUL, TUINT64}: ssa.OpMul64,
opAndType{OMUL, TFLOAT32}: ssa.OpMul32F,
opAndType{OMUL, TFLOAT64}: ssa.OpMul64F,
opAndType{ODIV, TFLOAT32}: ssa.OpDiv32F,
opAndType{ODIV, TFLOAT64}: ssa.OpDiv64F,
opAndType{ODIV, TINT8}: ssa.OpDiv8,
opAndType{ODIV, TUINT8}: ssa.OpDiv8u,
opAndType{ODIV, TINT16}: ssa.OpDiv16,
opAndType{ODIV, TUINT16}: ssa.OpDiv16u,
opAndType{ODIV, TINT32}: ssa.OpDiv32,
opAndType{ODIV, TUINT32}: ssa.OpDiv32u,
opAndType{ODIV, TINT64}: ssa.OpDiv64,
opAndType{ODIV, TUINT64}: ssa.OpDiv64u,
opAndType{OMOD, TINT8}: ssa.OpMod8,
opAndType{OMOD, TUINT8}: ssa.OpMod8u,
opAndType{OMOD, TINT16}: ssa.OpMod16,
opAndType{OMOD, TUINT16}: ssa.OpMod16u,
opAndType{OMOD, TINT32}: ssa.OpMod32,
opAndType{OMOD, TUINT32}: ssa.OpMod32u,
opAndType{OMOD, TINT64}: ssa.OpMod64,
opAndType{OMOD, TUINT64}: ssa.OpMod64u,
opAndType{OAND, TINT8}: ssa.OpAnd8,
opAndType{OAND, TUINT8}: ssa.OpAnd8,
opAndType{OAND, TINT16}: ssa.OpAnd16,
opAndType{OAND, TUINT16}: ssa.OpAnd16,
opAndType{OAND, TINT32}: ssa.OpAnd32,
opAndType{OAND, TUINT32}: ssa.OpAnd32,
opAndType{OAND, TINT64}: ssa.OpAnd64,
opAndType{OAND, TUINT64}: ssa.OpAnd64,
opAndType{OOR, TINT8}: ssa.OpOr8,
opAndType{OOR, TUINT8}: ssa.OpOr8,
opAndType{OOR, TINT16}: ssa.OpOr16,
opAndType{OOR, TUINT16}: ssa.OpOr16,
opAndType{OOR, TINT32}: ssa.OpOr32,
opAndType{OOR, TUINT32}: ssa.OpOr32,
opAndType{OOR, TINT64}: ssa.OpOr64,
opAndType{OOR, TUINT64}: ssa.OpOr64,
opAndType{OXOR, TINT8}: ssa.OpXor8,
opAndType{OXOR, TUINT8}: ssa.OpXor8,
opAndType{OXOR, TINT16}: ssa.OpXor16,
opAndType{OXOR, TUINT16}: ssa.OpXor16,
opAndType{OXOR, TINT32}: ssa.OpXor32,
opAndType{OXOR, TUINT32}: ssa.OpXor32,
opAndType{OXOR, TINT64}: ssa.OpXor64,
opAndType{OXOR, TUINT64}: ssa.OpXor64,
opAndType{OEQ, TBOOL}: ssa.OpEqB,
opAndType{OEQ, TINT8}: ssa.OpEq8,
opAndType{OEQ, TUINT8}: ssa.OpEq8,
opAndType{OEQ, TINT16}: ssa.OpEq16,
opAndType{OEQ, TUINT16}: ssa.OpEq16,
opAndType{OEQ, TINT32}: ssa.OpEq32,
opAndType{OEQ, TUINT32}: ssa.OpEq32,
opAndType{OEQ, TINT64}: ssa.OpEq64,
opAndType{OEQ, TUINT64}: ssa.OpEq64,
opAndType{OEQ, TINTER}: ssa.OpEqInter,
opAndType{OEQ, TSLICE}: ssa.OpEqSlice,
opAndType{OEQ, TFUNC}: ssa.OpEqPtr,
opAndType{OEQ, TMAP}: ssa.OpEqPtr,
opAndType{OEQ, TCHAN}: ssa.OpEqPtr,
opAndType{OEQ, TPTR}: ssa.OpEqPtr,
opAndType{OEQ, TUINTPTR}: ssa.OpEqPtr,
opAndType{OEQ, TUNSAFEPTR}: ssa.OpEqPtr,
opAndType{OEQ, TFLOAT64}: ssa.OpEq64F,
opAndType{OEQ, TFLOAT32}: ssa.OpEq32F,
opAndType{ONE, TBOOL}: ssa.OpNeqB,
opAndType{ONE, TINT8}: ssa.OpNeq8,
opAndType{ONE, TUINT8}: ssa.OpNeq8,
opAndType{ONE, TINT16}: ssa.OpNeq16,
opAndType{ONE, TUINT16}: ssa.OpNeq16,
opAndType{ONE, TINT32}: ssa.OpNeq32,
opAndType{ONE, TUINT32}: ssa.OpNeq32,
opAndType{ONE, TINT64}: ssa.OpNeq64,
opAndType{ONE, TUINT64}: ssa.OpNeq64,
opAndType{ONE, TINTER}: ssa.OpNeqInter,
opAndType{ONE, TSLICE}: ssa.OpNeqSlice,
opAndType{ONE, TFUNC}: ssa.OpNeqPtr,
opAndType{ONE, TMAP}: ssa.OpNeqPtr,
opAndType{ONE, TCHAN}: ssa.OpNeqPtr,
opAndType{ONE, TPTR}: ssa.OpNeqPtr,
opAndType{ONE, TUINTPTR}: ssa.OpNeqPtr,
opAndType{ONE, TUNSAFEPTR}: ssa.OpNeqPtr,
opAndType{ONE, TFLOAT64}: ssa.OpNeq64F,
opAndType{ONE, TFLOAT32}: ssa.OpNeq32F,
opAndType{OLT, TINT8}: ssa.OpLess8,
opAndType{OLT, TUINT8}: ssa.OpLess8U,
opAndType{OLT, TINT16}: ssa.OpLess16,
opAndType{OLT, TUINT16}: ssa.OpLess16U,
opAndType{OLT, TINT32}: ssa.OpLess32,
opAndType{OLT, TUINT32}: ssa.OpLess32U,
opAndType{OLT, TINT64}: ssa.OpLess64,
opAndType{OLT, TUINT64}: ssa.OpLess64U,
opAndType{OLT, TFLOAT64}: ssa.OpLess64F,
opAndType{OLT, TFLOAT32}: ssa.OpLess32F,
opAndType{OLE, TINT8}: ssa.OpLeq8,
opAndType{OLE, TUINT8}: ssa.OpLeq8U,
opAndType{OLE, TINT16}: ssa.OpLeq16,
opAndType{OLE, TUINT16}: ssa.OpLeq16U,
opAndType{OLE, TINT32}: ssa.OpLeq32,
opAndType{OLE, TUINT32}: ssa.OpLeq32U,
opAndType{OLE, TINT64}: ssa.OpLeq64,
opAndType{OLE, TUINT64}: ssa.OpLeq64U,
opAndType{OLE, TFLOAT64}: ssa.OpLeq64F,
opAndType{OLE, TFLOAT32}: ssa.OpLeq32F,
}
func (s *state) concreteEtype(t *types.Type) types.EType {
e := t.Etype
switch e {
default:
return e
case TINT:
if s.config.PtrSize == 8 {
return TINT64
}
return TINT32
case TUINT:
if s.config.PtrSize == 8 {
return TUINT64
}
return TUINT32
case TUINTPTR:
if s.config.PtrSize == 8 {
return TUINT64
}
return TUINT32
}
}
func (s *state) ssaOp(op Op, t *types.Type) ssa.Op {
etype := s.concreteEtype(t)
x, ok := opToSSA[opAndType{op, etype}]
if !ok {
s.Fatalf("unhandled binary op %v %s", op, etype)
}
return x
}
func floatForComplex(t *types.Type) *types.Type {
switch t.Etype {
case TCOMPLEX64:
return types.Types[TFLOAT32]
case TCOMPLEX128:
return types.Types[TFLOAT64]
}
Fatalf("unexpected type: %v", t)
return nil
}
func complexForFloat(t *types.Type) *types.Type {
switch t.Etype {
case TFLOAT32:
return types.Types[TCOMPLEX64]
case TFLOAT64:
return types.Types[TCOMPLEX128]
}
Fatalf("unexpected type: %v", t)
return nil
}
type opAndTwoTypes struct {
op Op
etype1 types.EType
etype2 types.EType
}
type twoTypes struct {
etype1 types.EType
etype2 types.EType
}
type twoOpsAndType struct {
op1 ssa.Op
op2 ssa.Op
intermediateType types.EType
}
var fpConvOpToSSA = map[twoTypes]twoOpsAndType{
twoTypes{TINT8, TFLOAT32}: twoOpsAndType{ssa.OpSignExt8to32, ssa.OpCvt32to32F, TINT32},
twoTypes{TINT16, TFLOAT32}: twoOpsAndType{ssa.OpSignExt16to32, ssa.OpCvt32to32F, TINT32},
twoTypes{TINT32, TFLOAT32}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt32to32F, TINT32},
twoTypes{TINT64, TFLOAT32}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt64to32F, TINT64},
twoTypes{TINT8, TFLOAT64}: twoOpsAndType{ssa.OpSignExt8to32, ssa.OpCvt32to64F, TINT32},
twoTypes{TINT16, TFLOAT64}: twoOpsAndType{ssa.OpSignExt16to32, ssa.OpCvt32to64F, TINT32},
twoTypes{TINT32, TFLOAT64}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt32to64F, TINT32},
twoTypes{TINT64, TFLOAT64}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt64to64F, TINT64},
twoTypes{TFLOAT32, TINT8}: twoOpsAndType{ssa.OpCvt32Fto32, ssa.OpTrunc32to8, TINT32},
twoTypes{TFLOAT32, TINT16}: twoOpsAndType{ssa.OpCvt32Fto32, ssa.OpTrunc32to16, TINT32},
twoTypes{TFLOAT32, TINT32}: twoOpsAndType{ssa.OpCvt32Fto32, ssa.OpCopy, TINT32},
twoTypes{TFLOAT32, TINT64}: twoOpsAndType{ssa.OpCvt32Fto64, ssa.OpCopy, TINT64},
twoTypes{TFLOAT64, TINT8}: twoOpsAndType{ssa.OpCvt64Fto32, ssa.OpTrunc32to8, TINT32},
twoTypes{TFLOAT64, TINT16}: twoOpsAndType{ssa.OpCvt64Fto32, ssa.OpTrunc32to16, TINT32},
twoTypes{TFLOAT64, TINT32}: twoOpsAndType{ssa.OpCvt64Fto32, ssa.OpCopy, TINT32},
twoTypes{TFLOAT64, TINT64}: twoOpsAndType{ssa.OpCvt64Fto64, ssa.OpCopy, TINT64},
// unsigned
twoTypes{TUINT8, TFLOAT32}: twoOpsAndType{ssa.OpZeroExt8to32, ssa.OpCvt32to32F, TINT32},
twoTypes{TUINT16, TFLOAT32}: twoOpsAndType{ssa.OpZeroExt16to32, ssa.OpCvt32to32F, TINT32},
twoTypes{TUINT32, TFLOAT32}: twoOpsAndType{ssa.OpZeroExt32to64, ssa.OpCvt64to32F, TINT64}, // go wide to dodge unsigned
twoTypes{TUINT64, TFLOAT32}: twoOpsAndType{ssa.OpCopy, ssa.OpInvalid, TUINT64}, // Cvt64Uto32F, branchy code expansion instead
twoTypes{TUINT8, TFLOAT64}: twoOpsAndType{ssa.OpZeroExt8to32, ssa.OpCvt32to64F, TINT32},
twoTypes{TUINT16, TFLOAT64}: twoOpsAndType{ssa.OpZeroExt16to32, ssa.OpCvt32to64F, TINT32},
twoTypes{TUINT32, TFLOAT64}: twoOpsAndType{ssa.OpZeroExt32to64, ssa.OpCvt64to64F, TINT64}, // go wide to dodge unsigned
twoTypes{TUINT64, TFLOAT64}: twoOpsAndType{ssa.OpCopy, ssa.OpInvalid, TUINT64}, // Cvt64Uto64F, branchy code expansion instead
twoTypes{TFLOAT32, TUINT8}: twoOpsAndType{ssa.OpCvt32Fto32, ssa.OpTrunc32to8, TINT32},
twoTypes{TFLOAT32, TUINT16}: twoOpsAndType{ssa.OpCvt32Fto32, ssa.OpTrunc32to16, TINT32},
twoTypes{TFLOAT32, TUINT32}: twoOpsAndType{ssa.OpCvt32Fto64, ssa.OpTrunc64to32, TINT64}, // go wide to dodge unsigned
twoTypes{TFLOAT32, TUINT64}: twoOpsAndType{ssa.OpInvalid, ssa.OpCopy, TUINT64}, // Cvt32Fto64U, branchy code expansion instead
twoTypes{TFLOAT64, TUINT8}: twoOpsAndType{ssa.OpCvt64Fto32, ssa.OpTrunc32to8, TINT32},
twoTypes{TFLOAT64, TUINT16}: twoOpsAndType{ssa.OpCvt64Fto32, ssa.OpTrunc32to16, TINT32},
twoTypes{TFLOAT64, TUINT32}: twoOpsAndType{ssa.OpCvt64Fto64, ssa.OpTrunc64to32, TINT64}, // go wide to dodge unsigned
twoTypes{TFLOAT64, TUINT64}: twoOpsAndType{ssa.OpInvalid, ssa.OpCopy, TUINT64}, // Cvt64Fto64U, branchy code expansion instead
// float
twoTypes{TFLOAT64, TFLOAT32}: twoOpsAndType{ssa.OpCvt64Fto32F, ssa.OpCopy, TFLOAT32},
twoTypes{TFLOAT64, TFLOAT64}: twoOpsAndType{ssa.OpRound64F, ssa.OpCopy, TFLOAT64},
twoTypes{TFLOAT32, TFLOAT32}: twoOpsAndType{ssa.OpRound32F, ssa.OpCopy, TFLOAT32},
twoTypes{TFLOAT32, TFLOAT64}: twoOpsAndType{ssa.OpCvt32Fto64F, ssa.OpCopy, TFLOAT64},
}
// this map is used only for 32-bit arch, and only includes the difference
// on 32-bit arch, don't use int64<->float conversion for uint32
var fpConvOpToSSA32 = map[twoTypes]twoOpsAndType{
twoTypes{TUINT32, TFLOAT32}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt32Uto32F, TUINT32},
twoTypes{TUINT32, TFLOAT64}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt32Uto64F, TUINT32},
twoTypes{TFLOAT32, TUINT32}: twoOpsAndType{ssa.OpCvt32Fto32U, ssa.OpCopy, TUINT32},
twoTypes{TFLOAT64, TUINT32}: twoOpsAndType{ssa.OpCvt64Fto32U, ssa.OpCopy, TUINT32},
}
// uint64<->float conversions, only on machines that have instructions for that
var uint64fpConvOpToSSA = map[twoTypes]twoOpsAndType{
twoTypes{TUINT64, TFLOAT32}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt64Uto32F, TUINT64},
twoTypes{TUINT64, TFLOAT64}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt64Uto64F, TUINT64},
twoTypes{TFLOAT32, TUINT64}: twoOpsAndType{ssa.OpCvt32Fto64U, ssa.OpCopy, TUINT64},
twoTypes{TFLOAT64, TUINT64}: twoOpsAndType{ssa.OpCvt64Fto64U, ssa.OpCopy, TUINT64},
}
var shiftOpToSSA = map[opAndTwoTypes]ssa.Op{
opAndTwoTypes{OLSH, TINT8, TUINT8}: ssa.OpLsh8x8,
opAndTwoTypes{OLSH, TUINT8, TUINT8}: ssa.OpLsh8x8,
opAndTwoTypes{OLSH, TINT8, TUINT16}: ssa.OpLsh8x16,
opAndTwoTypes{OLSH, TUINT8, TUINT16}: ssa.OpLsh8x16,
opAndTwoTypes{OLSH, TINT8, TUINT32}: ssa.OpLsh8x32,
opAndTwoTypes{OLSH, TUINT8, TUINT32}: ssa.OpLsh8x32,
opAndTwoTypes{OLSH, TINT8, TUINT64}: ssa.OpLsh8x64,
opAndTwoTypes{OLSH, TUINT8, TUINT64}: ssa.OpLsh8x64,
opAndTwoTypes{OLSH, TINT16, TUINT8}: ssa.OpLsh16x8,
opAndTwoTypes{OLSH, TUINT16, TUINT8}: ssa.OpLsh16x8,
opAndTwoTypes{OLSH, TINT16, TUINT16}: ssa.OpLsh16x16,
opAndTwoTypes{OLSH, TUINT16, TUINT16}: ssa.OpLsh16x16,
opAndTwoTypes{OLSH, TINT16, TUINT32}: ssa.OpLsh16x32,
opAndTwoTypes{OLSH, TUINT16, TUINT32}: ssa.OpLsh16x32,
opAndTwoTypes{OLSH, TINT16, TUINT64}: ssa.OpLsh16x64,
opAndTwoTypes{OLSH, TUINT16, TUINT64}: ssa.OpLsh16x64,
opAndTwoTypes{OLSH, TINT32, TUINT8}: ssa.OpLsh32x8,
opAndTwoTypes{OLSH, TUINT32, TUINT8}: ssa.OpLsh32x8,
opAndTwoTypes{OLSH, TINT32, TUINT16}: ssa.OpLsh32x16,
opAndTwoTypes{OLSH, TUINT32, TUINT16}: ssa.OpLsh32x16,
opAndTwoTypes{OLSH, TINT32, TUINT32}: ssa.OpLsh32x32,
opAndTwoTypes{OLSH, TUINT32, TUINT32}: ssa.OpLsh32x32,
opAndTwoTypes{OLSH, TINT32, TUINT64}: ssa.OpLsh32x64,
opAndTwoTypes{OLSH, TUINT32, TUINT64}: ssa.OpLsh32x64,
opAndTwoTypes{OLSH, TINT64, TUINT8}: ssa.OpLsh64x8,
opAndTwoTypes{OLSH, TUINT64, TUINT8}: ssa.OpLsh64x8,
opAndTwoTypes{OLSH, TINT64, TUINT16}: ssa.OpLsh64x16,
opAndTwoTypes{OLSH, TUINT64, TUINT16}: ssa.OpLsh64x16,
opAndTwoTypes{OLSH, TINT64, TUINT32}: ssa.OpLsh64x32,
opAndTwoTypes{OLSH, TUINT64, TUINT32}: ssa.OpLsh64x32,
opAndTwoTypes{OLSH, TINT64, TUINT64}: ssa.OpLsh64x64,
opAndTwoTypes{OLSH, TUINT64, TUINT64}: ssa.OpLsh64x64,
opAndTwoTypes{ORSH, TINT8, TUINT8}: ssa.OpRsh8x8,
opAndTwoTypes{ORSH, TUINT8, TUINT8}: ssa.OpRsh8Ux8,
opAndTwoTypes{ORSH, TINT8, TUINT16}: ssa.OpRsh8x16,
opAndTwoTypes{ORSH, TUINT8, TUINT16}: ssa.OpRsh8Ux16,
opAndTwoTypes{ORSH, TINT8, TUINT32}: ssa.OpRsh8x32,
opAndTwoTypes{ORSH, TUINT8, TUINT32}: ssa.OpRsh8Ux32,
opAndTwoTypes{ORSH, TINT8, TUINT64}: ssa.OpRsh8x64,
opAndTwoTypes{ORSH, TUINT8, TUINT64}: ssa.OpRsh8Ux64,
opAndTwoTypes{ORSH, TINT16, TUINT8}: ssa.OpRsh16x8,
opAndTwoTypes{ORSH, TUINT16, TUINT8}: ssa.OpRsh16Ux8,
opAndTwoTypes{ORSH, TINT16, TUINT16}: ssa.OpRsh16x16,
opAndTwoTypes{ORSH, TUINT16, TUINT16}: ssa.OpRsh16Ux16,
opAndTwoTypes{ORSH, TINT16, TUINT32}: ssa.OpRsh16x32,
opAndTwoTypes{ORSH, TUINT16, TUINT32}: ssa.OpRsh16Ux32,
opAndTwoTypes{ORSH, TINT16, TUINT64}: ssa.OpRsh16x64,
opAndTwoTypes{ORSH, TUINT16, TUINT64}: ssa.OpRsh16Ux64,
opAndTwoTypes{ORSH, TINT32, TUINT8}: ssa.OpRsh32x8,
opAndTwoTypes{ORSH, TUINT32, TUINT8}: ssa.OpRsh32Ux8,
opAndTwoTypes{ORSH, TINT32, TUINT16}: ssa.OpRsh32x16,
opAndTwoTypes{ORSH, TUINT32, TUINT16}: ssa.OpRsh32Ux16,
opAndTwoTypes{ORSH, TINT32, TUINT32}: ssa.OpRsh32x32,
opAndTwoTypes{ORSH, TUINT32, TUINT32}: ssa.OpRsh32Ux32,
opAndTwoTypes{ORSH, TINT32, TUINT64}: ssa.OpRsh32x64,
opAndTwoTypes{ORSH, TUINT32, TUINT64}: ssa.OpRsh32Ux64,
opAndTwoTypes{ORSH, TINT64, TUINT8}: ssa.OpRsh64x8,
opAndTwoTypes{ORSH, TUINT64, TUINT8}: ssa.OpRsh64Ux8,
opAndTwoTypes{ORSH, TINT64, TUINT16}: ssa.OpRsh64x16,
opAndTwoTypes{ORSH, TUINT64, TUINT16}: ssa.OpRsh64Ux16,
opAndTwoTypes{ORSH, TINT64, TUINT32}: ssa.OpRsh64x32,
opAndTwoTypes{ORSH, TUINT64, TUINT32}: ssa.OpRsh64Ux32,
opAndTwoTypes{ORSH, TINT64, TUINT64}: ssa.OpRsh64x64,
opAndTwoTypes{ORSH, TUINT64, TUINT64}: ssa.OpRsh64Ux64,
}
func (s *state) ssaShiftOp(op Op, t *types.Type, u *types.Type) ssa.Op {
etype1 := s.concreteEtype(t)
etype2 := s.concreteEtype(u)
x, ok := shiftOpToSSA[opAndTwoTypes{op, etype1, etype2}]
if !ok {
s.Fatalf("unhandled shift op %v etype=%s/%s", op, etype1, etype2)
}
return x
}
// expr converts the expression n to ssa, adds it to s and returns the ssa result.
func (s *state) expr(n *Node) *ssa.Value {
if !(n.Op == ONAME || n.Op == OLITERAL && n.Sym != nil) {
// ONAMEs and named OLITERALs have the line number
// of the decl, not the use. See issue 14742.
s.pushLine(n.Pos)
defer s.popLine()
}
s.stmtList(n.Ninit)
switch n.Op {
case OBYTES2STRTMP:
slice := s.expr(n.Left)
ptr := s.newValue1(ssa.OpSlicePtr, s.f.Config.Types.BytePtr, slice)
len := s.newValue1(ssa.OpSliceLen, types.Types[TINT], slice)
return s.newValue2(ssa.OpStringMake, n.Type, ptr, len)
case OSTR2BYTESTMP:
str := s.expr(n.Left)
ptr := s.newValue1(ssa.OpStringPtr, s.f.Config.Types.BytePtr, str)
len := s.newValue1(ssa.OpStringLen, types.Types[TINT], str)
return s.newValue3(ssa.OpSliceMake, n.Type, ptr, len, len)
case OCFUNC:
aux := n.Left.Sym.Linksym()
return s.entryNewValue1A(ssa.OpAddr, n.Type, aux, s.sb)
case ONAME:
if n.Class() == PFUNC {
// "value" of a function is the address of the function's closure
sym := funcsym(n.Sym).Linksym()
return s.entryNewValue1A(ssa.OpAddr, types.NewPtr(n.Type), sym, s.sb)
}
if s.canSSA(n) {
return s.variable(n, n.Type)
}
addr := s.addr(n)
return s.load(n.Type, addr)
case OCLOSUREVAR:
addr := s.addr(n)
return s.load(n.Type, addr)
case OLITERAL:
switch u := n.Val().U.(type) {
case *Mpint:
i := u.Int64()
switch n.Type.Size() {
case 1:
return s.constInt8(n.Type, int8(i))
case 2:
return s.constInt16(n.Type, int16(i))
case 4:
return s.constInt32(n.Type, int32(i))
case 8:
return s.constInt64(n.Type, i)
default:
s.Fatalf("bad integer size %d", n.Type.Size())
return nil
}
case string:
if u == "" {
return s.constEmptyString(n.Type)
}
return s.entryNewValue0A(ssa.OpConstString, n.Type, u)
case bool:
return s.constBool(u)
case *NilVal:
t := n.Type
switch {
case t.IsSlice():
return s.constSlice(t)
case t.IsInterface():
return s.constInterface(t)
default:
return s.constNil(t)
}
case *Mpflt:
switch n.Type.Size() {
case 4:
return s.constFloat32(n.Type, u.Float32())
case 8:
return s.constFloat64(n.Type, u.Float64())
default:
s.Fatalf("bad float size %d", n.Type.Size())
return nil
}
case *Mpcplx:
r := &u.Real
i := &u.Imag
switch n.Type.Size() {
case 8:
pt := types.Types[TFLOAT32]
return s.newValue2(ssa.OpComplexMake, n.Type,
s.constFloat32(pt, r.Float32()),
s.constFloat32(pt, i.Float32()))
case 16:
pt := types.Types[TFLOAT64]
return s.newValue2(ssa.OpComplexMake, n.Type,
s.constFloat64(pt, r.Float64()),
s.constFloat64(pt, i.Float64()))
default:
s.Fatalf("bad float size %d", n.Type.Size())
return nil
}
default:
s.Fatalf("unhandled OLITERAL %v", n.Val().Ctype())
return nil
}
case OCONVNOP:
to := n.Type
from := n.Left.Type
// Assume everything will work out, so set up our return value.
// Anything interesting that happens from here is a fatal.
x := s.expr(n.Left)
// Special case for not confusing GC and liveness.
// We don't want pointers accidentally classified
// as not-pointers or vice-versa because of copy
// elision.
if to.IsPtrShaped() != from.IsPtrShaped() {
return s.newValue2(ssa.OpConvert, to, x, s.mem())
}
v := s.newValue1(ssa.OpCopy, to, x) // ensure that v has the right type
// CONVNOP closure
if to.Etype == TFUNC && from.IsPtrShaped() {
return v
}
// named <--> unnamed type or typed <--> untyped const
if from.Etype == to.Etype {
return v
}
// unsafe.Pointer <--> *T
if to.Etype == TUNSAFEPTR && from.IsPtrShaped() || from.Etype == TUNSAFEPTR && to.IsPtrShaped() {
return v
}
// map <--> *hmap
if to.Etype == TMAP && from.IsPtr() &&
to.MapType().Hmap == from.Elem() {
return v
}
dowidth(from)
dowidth(to)
if from.Width != to.Width {
s.Fatalf("CONVNOP width mismatch %v (%d) -> %v (%d)\n", from, from.Width, to, to.Width)
return nil
}
if etypesign(from.Etype) != etypesign(to.Etype) {
s.Fatalf("CONVNOP sign mismatch %v (%s) -> %v (%s)\n", from, from.Etype, to, to.Etype)
return nil
}
if instrumenting {
// These appear to be fine, but they fail the
// integer constraint below, so okay them here.
// Sample non-integer conversion: map[string]string -> *uint8
return v
}
if etypesign(from.Etype) == 0 {
s.Fatalf("CONVNOP unrecognized non-integer %v -> %v\n", from, to)
return nil
}
// integer, same width, same sign
return v
case OCONV:
x := s.expr(n.Left)
ft := n.Left.Type // from type
tt := n.Type // to type
if ft.IsBoolean() && tt.IsKind(TUINT8) {
// Bool -> uint8 is generated internally when indexing into runtime.staticbyte.
return s.newValue1(ssa.OpCopy, n.Type, x)
}
if ft.IsInteger() && tt.IsInteger() {
var op ssa.Op
if tt.Size() == ft.Size() {
op = ssa.OpCopy
} else if tt.Size() < ft.Size() {
// truncation
switch 10*ft.Size() + tt.Size() {
case 21:
op = ssa.OpTrunc16to8
case 41:
op = ssa.OpTrunc32to8
case 42:
op = ssa.OpTrunc32to16
case 81:
op = ssa.OpTrunc64to8
case 82:
op = ssa.OpTrunc64to16
case 84:
op = ssa.OpTrunc64to32
default:
s.Fatalf("weird integer truncation %v -> %v", ft, tt)
}
} else if ft.IsSigned() {
// sign extension
switch 10*ft.Size() + tt.Size() {
case 12:
op = ssa.OpSignExt8to16
case 14:
op = ssa.OpSignExt8to32
case 18:
op = ssa.OpSignExt8to64
case 24:
op = ssa.OpSignExt16to32
case 28:
op = ssa.OpSignExt16to64
case 48:
op = ssa.OpSignExt32to64
default:
s.Fatalf("bad integer sign extension %v -> %v", ft, tt)
}
} else {
// zero extension
switch 10*ft.Size() + tt.Size() {
case 12:
op = ssa.OpZeroExt8to16
case 14:
op = ssa.OpZeroExt8to32
case 18:
op = ssa.OpZeroExt8to64
case 24:
op = ssa.OpZeroExt16to32
case 28:
op = ssa.OpZeroExt16to64
case 48:
op = ssa.OpZeroExt32to64
default:
s.Fatalf("weird integer sign extension %v -> %v", ft, tt)
}
}
return s.newValue1(op, n.Type, x)
}
if ft.IsFloat() || tt.IsFloat() {
conv, ok := fpConvOpToSSA[twoTypes{s.concreteEtype(ft), s.concreteEtype(tt)}]
if s.config.RegSize == 4 && thearch.LinkArch.Family != sys.MIPS && !s.softFloat {
if conv1, ok1 := fpConvOpToSSA32[twoTypes{s.concreteEtype(ft), s.concreteEtype(tt)}]; ok1 {
conv = conv1
}
}
if thearch.LinkArch.Family == sys.ARM64 || thearch.LinkArch.Family == sys.Wasm || thearch.LinkArch.Family == sys.S390X || s.softFloat {
if conv1, ok1 := uint64fpConvOpToSSA[twoTypes{s.concreteEtype(ft), s.concreteEtype(tt)}]; ok1 {
conv = conv1
}
}
if thearch.LinkArch.Family == sys.MIPS && !s.softFloat {
if ft.Size() == 4 && ft.IsInteger() && !ft.IsSigned() {
// tt is float32 or float64, and ft is also unsigned
if tt.Size() == 4 {
return s.uint32Tofloat32(n, x, ft, tt)
}
if tt.Size() == 8 {
return s.uint32Tofloat64(n, x, ft, tt)
}
} else if tt.Size() == 4 && tt.IsInteger() && !tt.IsSigned() {
// ft is float32 or float64, and tt is unsigned integer
if ft.Size() == 4 {
return s.float32ToUint32(n, x, ft, tt)
}
if ft.Size() == 8 {
return s.float64ToUint32(n, x, ft, tt)
}
}
}
if !ok {
s.Fatalf("weird float conversion %v -> %v", ft, tt)
}
op1, op2, it := conv.op1, conv.op2, conv.intermediateType
if op1 != ssa.OpInvalid && op2 != ssa.OpInvalid {
// normal case, not tripping over unsigned 64
if op1 == ssa.OpCopy {
if op2 == ssa.OpCopy {
return x
}
return s.newValueOrSfCall1(op2, n.Type, x)
}
if op2 == ssa.OpCopy {
return s.newValueOrSfCall1(op1, n.Type, x)
}
return s.newValueOrSfCall1(op2, n.Type, s.newValueOrSfCall1(op1, types.Types[it], x))
}
// Tricky 64-bit unsigned cases.
if ft.IsInteger() {
// tt is float32 or float64, and ft is also unsigned
if tt.Size() == 4 {
return s.uint64Tofloat32(n, x, ft, tt)
}
if tt.Size() == 8 {
return s.uint64Tofloat64(n, x, ft, tt)
}
s.Fatalf("weird unsigned integer to float conversion %v -> %v", ft, tt)
}
// ft is float32 or float64, and tt is unsigned integer
if ft.Size() == 4 {
return s.float32ToUint64(n, x, ft, tt)
}
if ft.Size() == 8 {
return s.float64ToUint64(n, x, ft, tt)
}
s.Fatalf("weird float to unsigned integer conversion %v -> %v", ft, tt)
return nil
}
if ft.IsComplex() && tt.IsComplex() {
var op ssa.Op
if ft.Size() == tt.Size() {
switch ft.Size() {
case 8:
op = ssa.OpRound32F
case 16:
op = ssa.OpRound64F
default:
s.Fatalf("weird complex conversion %v -> %v", ft, tt)
}
} else if ft.Size() == 8 && tt.Size() == 16 {
op = ssa.OpCvt32Fto64F
} else if ft.Size() == 16 && tt.Size() == 8 {
op = ssa.OpCvt64Fto32F
} else {
s.Fatalf("weird complex conversion %v -> %v", ft, tt)
}
ftp := floatForComplex(ft)
ttp := floatForComplex(tt)
return s.newValue2(ssa.OpComplexMake, tt,
s.newValueOrSfCall1(op, ttp, s.newValue1(ssa.OpComplexReal, ftp, x)),
s.newValueOrSfCall1(op, ttp, s.newValue1(ssa.OpComplexImag, ftp, x)))
}
s.Fatalf("unhandled OCONV %s -> %s", n.Left.Type.Etype, n.Type.Etype)
return nil
case ODOTTYPE:
res, _ := s.dottype(n, false)
return res
// binary ops
case OLT, OEQ, ONE, OLE, OGE, OGT:
a := s.expr(n.Left)
b := s.expr(n.Right)
if n.Left.Type.IsComplex() {
pt := floatForComplex(n.Left.Type)
op := s.ssaOp(OEQ, pt)
r := s.newValueOrSfCall2(op, types.Types[TBOOL], s.newValue1(ssa.OpComplexReal, pt, a), s.newValue1(ssa.OpComplexReal, pt, b))
i := s.newValueOrSfCall2(op, types.Types[TBOOL], s.newValue1(ssa.OpComplexImag, pt, a), s.newValue1(ssa.OpComplexImag, pt, b))
c := s.newValue2(ssa.OpAndB, types.Types[TBOOL], r, i)
switch n.Op {
case OEQ:
return c
case ONE:
return s.newValue1(ssa.OpNot, types.Types[TBOOL], c)
default:
s.Fatalf("ordered complex compare %v", n.Op)
}
}
// Convert OGE and OGT into OLE and OLT.
op := n.Op
switch op {
case OGE:
op, a, b = OLE, b, a
case OGT:
op, a, b = OLT, b, a
}
if n.Left.Type.IsFloat() {
// float comparison
return s.newValueOrSfCall2(s.ssaOp(op, n.Left.Type), types.Types[TBOOL], a, b)
}
// integer comparison
return s.newValue2(s.ssaOp(op, n.Left.Type), types.Types[TBOOL], a, b)
case OMUL:
a := s.expr(n.Left)
b := s.expr(n.Right)
if n.Type.IsComplex() {
mulop := ssa.OpMul64F
addop := ssa.OpAdd64F
subop := ssa.OpSub64F
pt := floatForComplex(n.Type) // Could be Float32 or Float64
wt := types.Types[TFLOAT64] // Compute in Float64 to minimize cancellation error
areal := s.newValue1(ssa.OpComplexReal, pt, a)
breal := s.newValue1(ssa.OpComplexReal, pt, b)
aimag := s.newValue1(ssa.OpComplexImag, pt, a)
bimag := s.newValue1(ssa.OpComplexImag, pt, b)
if pt != wt { // Widen for calculation
areal = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, areal)
breal = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, breal)
aimag = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, aimag)
bimag = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, bimag)
}
xreal := s.newValueOrSfCall2(subop, wt, s.newValueOrSfCall2(mulop, wt, areal, breal), s.newValueOrSfCall2(mulop, wt, aimag, bimag))
ximag := s.newValueOrSfCall2(addop, wt, s.newValueOrSfCall2(mulop, wt, areal, bimag), s.newValueOrSfCall2(mulop, wt, aimag, breal))
if pt != wt { // Narrow to store back
xreal = s.newValueOrSfCall1(ssa.OpCvt64Fto32F, pt, xreal)
ximag = s.newValueOrSfCall1(ssa.OpCvt64Fto32F, pt, ximag)
}
return s.newValue2(ssa.OpComplexMake, n.Type, xreal, ximag)
}
if n.Type.IsFloat() {
return s.newValueOrSfCall2(s.ssaOp(n.Op, n.Type), a.Type, a, b)
}
return s.newValue2(s.ssaOp(n.Op, n.Type), a.Type, a, b)
case ODIV:
a := s.expr(n.Left)
b := s.expr(n.Right)
if n.Type.IsComplex() {
// TODO this is not executed because the front-end substitutes a runtime call.
// That probably ought to change; with modest optimization the widen/narrow
// conversions could all be elided in larger expression trees.
mulop := ssa.OpMul64F
addop := ssa.OpAdd64F
subop := ssa.OpSub64F
divop := ssa.OpDiv64F
pt := floatForComplex(n.Type) // Could be Float32 or Float64
wt := types.Types[TFLOAT64] // Compute in Float64 to minimize cancellation error
areal := s.newValue1(ssa.OpComplexReal, pt, a)
breal := s.newValue1(ssa.OpComplexReal, pt, b)
aimag := s.newValue1(ssa.OpComplexImag, pt, a)
bimag := s.newValue1(ssa.OpComplexImag, pt, b)
if pt != wt { // Widen for calculation
areal = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, areal)
breal = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, breal)
aimag = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, aimag)
bimag = s.newValueOrSfCall1(ssa.OpCvt32Fto64F, wt, bimag)
}
denom := s.newValueOrSfCall2(addop, wt, s.newValueOrSfCall2(mulop, wt, breal, breal), s.newValueOrSfCall2(mulop, wt, bimag, bimag))
xreal := s.newValueOrSfCall2(addop, wt, s.newValueOrSfCall2(mulop, wt, areal, breal), s.newValueOrSfCall2(mulop, wt, aimag, bimag))
ximag := s.newValueOrSfCall2(subop, wt, s.newValueOrSfCall2(mulop, wt, aimag, breal), s.newValueOrSfCall2(mulop, wt, areal, bimag))
// TODO not sure if this is best done in wide precision or narrow
// Double-rounding might be an issue.
// Note that the pre-SSA implementation does the entire calculation
// in wide format, so wide is compatible.
xreal = s.newValueOrSfCall2(divop, wt, xreal, denom)
ximag = s.newValueOrSfCall2(divop, wt, ximag, denom)
if pt != wt { // Narrow to store back
xreal = s.newValueOrSfCall1(ssa.OpCvt64Fto32F, pt, xreal)
ximag = s.newValueOrSfCall1(ssa.OpCvt64Fto32F, pt, ximag)
}
return s.newValue2(ssa.OpComplexMake, n.Type, xreal, ximag)
}
if n.Type.IsFloat() {
return s.newValueOrSfCall2(s.ssaOp(n.Op, n.Type), a.Type, a, b)
}
return s.intDivide(n, a, b)
case OMOD:
a := s.expr(n.Left)
b := s.expr(n.Right)
return s.intDivide(n, a, b)
case OADD, OSUB:
a := s.expr(n.Left)
b := s.expr(n.Right)
if n.Type.IsComplex() {
pt := floatForComplex(n.Type)
op := s.ssaOp(n.Op, pt)
return s.newValue2(ssa.OpComplexMake, n.Type,
s.newValueOrSfCall2(op, pt, s.newValue1(ssa.OpComplexReal, pt, a), s.newValue1(ssa.OpComplexReal, pt, b)),
s.newValueOrSfCall2(op, pt, s.newValue1(ssa.OpComplexImag, pt, a), s.newValue1(ssa.OpComplexImag, pt, b)))
}
if n.Type.IsFloat() {
return s.newValueOrSfCall2(s.ssaOp(n.Op, n.Type), a.Type, a, b)
}
return s.newValue2(s.ssaOp(n.Op, n.Type), a.Type, a, b)
case OAND, OOR, OXOR:
a := s.expr(n.Left)
b := s.expr(n.Right)
return s.newValue2(s.ssaOp(n.Op, n.Type), a.Type, a, b)
case OLSH, ORSH:
a := s.expr(n.Left)
b := s.expr(n.Right)
bt := b.Type
if bt.IsSigned() {
cmp := s.newValue2(s.ssaOp(OLE, bt), types.Types[TBOOL], s.zeroVal(bt), b)
s.check(cmp, panicshift)
bt = bt.ToUnsigned()
}
return s.newValue2(s.ssaShiftOp(n.Op, n.Type, bt), a.Type, a, b)
case OANDAND, OOROR:
// To implement OANDAND (and OOROR), we introduce a
// new temporary variable to hold the result. The
// variable is associated with the OANDAND node in the
// s.vars table (normally variables are only
// associated with ONAME nodes). We convert
// A && B
// to
// var = A
// if var {
// var = B
// }
// Using var in the subsequent block introduces the
// necessary phi variable.
el := s.expr(n.Left)
s.vars[n] = el
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(el)
// In theory, we should set b.Likely here based on context.
// However, gc only gives us likeliness hints
// in a single place, for plain OIF statements,
// and passing around context is finnicky, so don't bother for now.
bRight := s.f.NewBlock(ssa.BlockPlain)
bResult := s.f.NewBlock(ssa.BlockPlain)
if n.Op == OANDAND {
b.AddEdgeTo(bRight)
b.AddEdgeTo(bResult)
} else if n.Op == OOROR {
b.AddEdgeTo(bResult)
b.AddEdgeTo(bRight)
}
s.startBlock(bRight)
er := s.expr(n.Right)
s.vars[n] = er
b = s.endBlock()
b.AddEdgeTo(bResult)
s.startBlock(bResult)
return s.variable(n, types.Types[TBOOL])
case OCOMPLEX:
r := s.expr(n.Left)
i := s.expr(n.Right)
return s.newValue2(ssa.OpComplexMake, n.Type, r, i)
// unary ops
case ONEG:
a := s.expr(n.Left)
if n.Type.IsComplex() {
tp := floatForComplex(n.Type)
negop := s.ssaOp(n.Op, tp)
return s.newValue2(ssa.OpComplexMake, n.Type,
s.newValue1(negop, tp, s.newValue1(ssa.OpComplexReal, tp, a)),
s.newValue1(negop, tp, s.newValue1(ssa.OpComplexImag, tp, a)))
}
return s.newValue1(s.ssaOp(n.Op, n.Type), a.Type, a)
case ONOT, OBITNOT:
a := s.expr(n.Left)
return s.newValue1(s.ssaOp(n.Op, n.Type), a.Type, a)
case OIMAG, OREAL:
a := s.expr(n.Left)
return s.newValue1(s.ssaOp(n.Op, n.Left.Type), n.Type, a)
case OPLUS:
return s.expr(n.Left)
case OADDR:
return s.addr(n.Left)
case ORESULT:
addr := s.constOffPtrSP(types.NewPtr(n.Type), n.Xoffset)
return s.load(n.Type, addr)
case ODEREF:
p := s.exprPtr(n.Left, n.Bounded(), n.Pos)
return s.load(n.Type, p)
case ODOT:
if n.Left.Op == OSTRUCTLIT {
// All literals with nonzero fields have already been
// rewritten during walk. Any that remain are just T{}
// or equivalents. Use the zero value.
if !isZero(n.Left) {
s.Fatalf("literal with nonzero value in SSA: %v", n.Left)
}
return s.zeroVal(n.Type)
}
// If n is addressable and can't be represented in
// SSA, then load just the selected field. This
// prevents false memory dependencies in race/msan
// instrumentation.
if islvalue(n) && !s.canSSA(n) {
p := s.addr(n)
return s.load(n.Type, p)
}
v := s.expr(n.Left)
return s.newValue1I(ssa.OpStructSelect, n.Type, int64(fieldIdx(n)), v)
case ODOTPTR:
p := s.exprPtr(n.Left, n.Bounded(), n.Pos)
p = s.newValue1I(ssa.OpOffPtr, types.NewPtr(n.Type), n.Xoffset, p)
return s.load(n.Type, p)
case OINDEX:
switch {
case n.Left.Type.IsString():
if n.Bounded() && Isconst(n.Left, CTSTR) && Isconst(n.Right, CTINT) {
// Replace "abc"[1] with 'b'.
// Delayed until now because "abc"[1] is not an ideal constant.
// See test/fixedbugs/issue11370.go.
return s.newValue0I(ssa.OpConst8, types.Types[TUINT8], int64(int8(strlit(n.Left)[n.Right.Int64()])))
}
a := s.expr(n.Left)
i := s.expr(n.Right)
len := s.newValue1(ssa.OpStringLen, types.Types[TINT], a)
i = s.boundsCheck(i, len, ssa.BoundsIndex, n.Bounded())
ptrtyp := s.f.Config.Types.BytePtr
ptr := s.newValue1(ssa.OpStringPtr, ptrtyp, a)
if Isconst(n.Right, CTINT) {
ptr = s.newValue1I(ssa.OpOffPtr, ptrtyp, n.Right.Int64(), ptr)
} else {
ptr = s.newValue2(ssa.OpAddPtr, ptrtyp, ptr, i)
}
return s.load(types.Types[TUINT8], ptr)
case n.Left.Type.IsSlice():
p := s.addr(n)
return s.load(n.Left.Type.Elem(), p)
case n.Left.Type.IsArray():
if canSSAType(n.Left.Type) {
// SSA can handle arrays of length at most 1.
bound := n.Left.Type.NumElem()
a := s.expr(n.Left)
i := s.expr(n.Right)
if bound == 0 {
// Bounds check will never succeed. Might as well
// use constants for the bounds check.
z := s.constInt(types.Types[TINT], 0)
s.boundsCheck(z, z, ssa.BoundsIndex, false)
// The return value won't be live, return junk.
return s.newValue0(ssa.OpUnknown, n.Type)
}
len := s.constInt(types.Types[TINT], bound)
s.boundsCheck(i, len, ssa.BoundsIndex, n.Bounded()) // checks i == 0
return s.newValue1I(ssa.OpArraySelect, n.Type, 0, a)
}
p := s.addr(n)
return s.load(n.Left.Type.Elem(), p)
default:
s.Fatalf("bad type for index %v", n.Left.Type)
return nil
}
case OLEN, OCAP:
switch {
case n.Left.Type.IsSlice():
op := ssa.OpSliceLen
if n.Op == OCAP {
op = ssa.OpSliceCap
}
return s.newValue1(op, types.Types[TINT], s.expr(n.Left))
case n.Left.Type.IsString(): // string; not reachable for OCAP
return s.newValue1(ssa.OpStringLen, types.Types[TINT], s.expr(n.Left))
case n.Left.Type.IsMap(), n.Left.Type.IsChan():
return s.referenceTypeBuiltin(n, s.expr(n.Left))
default: // array
return s.constInt(types.Types[TINT], n.Left.Type.NumElem())
}
case OSPTR:
a := s.expr(n.Left)
if n.Left.Type.IsSlice() {
return s.newValue1(ssa.OpSlicePtr, n.Type, a)
} else {
return s.newValue1(ssa.OpStringPtr, n.Type, a)
}
case OITAB:
a := s.expr(n.Left)
return s.newValue1(ssa.OpITab, n.Type, a)
case OIDATA:
a := s.expr(n.Left)
return s.newValue1(ssa.OpIData, n.Type, a)
case OEFACE:
tab := s.expr(n.Left)
data := s.expr(n.Right)
return s.newValue2(ssa.OpIMake, n.Type, tab, data)
case OSLICEHEADER:
p := s.expr(n.Left)
l := s.expr(n.List.First())
c := s.expr(n.List.Second())
return s.newValue3(ssa.OpSliceMake, n.Type, p, l, c)
case OSLICE, OSLICEARR, OSLICE3, OSLICE3ARR:
v := s.expr(n.Left)
var i, j, k *ssa.Value
low, high, max := n.SliceBounds()
if low != nil {
i = s.expr(low)
}
if high != nil {
j = s.expr(high)
}
if max != nil {
k = s.expr(max)
}
p, l, c := s.slice(v, i, j, k, n.Bounded())
return s.newValue3(ssa.OpSliceMake, n.Type, p, l, c)
case OSLICESTR:
v := s.expr(n.Left)
var i, j *ssa.Value
low, high, _ := n.SliceBounds()
if low != nil {
i = s.expr(low)
}
if high != nil {
j = s.expr(high)
}
p, l, _ := s.slice(v, i, j, nil, n.Bounded())
return s.newValue2(ssa.OpStringMake, n.Type, p, l)
case OCALLFUNC:
if isIntrinsicCall(n) {
return s.intrinsicCall(n)
}
fallthrough
case OCALLINTER, OCALLMETH:
a := s.call(n, callNormal)
return s.load(n.Type, a)
case OGETG:
return s.newValue1(ssa.OpGetG, n.Type, s.mem())
case OAPPEND:
return s.append(n, false)
case OSTRUCTLIT, OARRAYLIT:
// All literals with nonzero fields have already been
// rewritten during walk. Any that remain are just T{}
// or equivalents. Use the zero value.
if !isZero(n) {
s.Fatalf("literal with nonzero value in SSA: %v", n)
}
return s.zeroVal(n.Type)
case ONEWOBJ:
if n.Type.Elem().Size() == 0 {
return s.newValue1A(ssa.OpAddr, n.Type, zerobaseSym, s.sb)
}
typ := s.expr(n.Left)
vv := s.rtcall(newobject, true, []*types.Type{n.Type}, typ)
return vv[0]
default:
s.Fatalf("unhandled expr %v", n.Op)
return nil
}
}
// append converts an OAPPEND node to SSA.
// If inplace is false, it converts the OAPPEND expression n to an ssa.Value,
// adds it to s, and returns the Value.
// If inplace is true, it writes the result of the OAPPEND expression n
// back to the slice being appended to, and returns nil.
// inplace MUST be set to false if the slice can be SSA'd.
func (s *state) append(n *Node, inplace bool) *ssa.Value {
// If inplace is false, process as expression "append(s, e1, e2, e3)":
//
// ptr, len, cap := s
// newlen := len + 3
// if newlen > cap {
// ptr, len, cap = growslice(s, newlen)
// newlen = len + 3 // recalculate to avoid a spill
// }
// // with write barriers, if needed:
// *(ptr+len) = e1
// *(ptr+len+1) = e2
// *(ptr+len+2) = e3
// return makeslice(ptr, newlen, cap)
//
//
// If inplace is true, process as statement "s = append(s, e1, e2, e3)":
//
// a := &s
// ptr, len, cap := s
// newlen := len + 3
// if uint(newlen) > uint(cap) {
// newptr, len, newcap = growslice(ptr, len, cap, newlen)
// vardef(a) // if necessary, advise liveness we are writing a new a
// *a.cap = newcap // write before ptr to avoid a spill
// *a.ptr = newptr // with write barrier
// }
// newlen = len + 3 // recalculate to avoid a spill
// *a.len = newlen
// // with write barriers, if needed:
// *(ptr+len) = e1
// *(ptr+len+1) = e2
// *(ptr+len+2) = e3
et := n.Type.Elem()
pt := types.NewPtr(et)
// Evaluate slice
sn := n.List.First() // the slice node is the first in the list
var slice, addr *ssa.Value
if inplace {
addr = s.addr(sn)
slice = s.load(n.Type, addr)
} else {
slice = s.expr(sn)
}
// Allocate new blocks
grow := s.f.NewBlock(ssa.BlockPlain)
assign := s.f.NewBlock(ssa.BlockPlain)
// Decide if we need to grow
nargs := int64(n.List.Len() - 1)
p := s.newValue1(ssa.OpSlicePtr, pt, slice)
l := s.newValue1(ssa.OpSliceLen, types.Types[TINT], slice)
c := s.newValue1(ssa.OpSliceCap, types.Types[TINT], slice)
nl := s.newValue2(s.ssaOp(OADD, types.Types[TINT]), types.Types[TINT], l, s.constInt(types.Types[TINT], nargs))
cmp := s.newValue2(s.ssaOp(OLT, types.Types[TUINT]), types.Types[TBOOL], c, nl)
s.vars[&ptrVar] = p
if !inplace {
s.vars[&newlenVar] = nl
s.vars[&capVar] = c
} else {
s.vars[&lenVar] = l
}
b := s.endBlock()
b.Kind = ssa.BlockIf
b.Likely = ssa.BranchUnlikely
b.SetControl(cmp)
b.AddEdgeTo(grow)
b.AddEdgeTo(assign)
// Call growslice
s.startBlock(grow)
taddr := s.expr(n.Left)
r := s.rtcall(growslice, true, []*types.Type{pt, types.Types[TINT], types.Types[TINT]}, taddr, p, l, c, nl)
if inplace {
if sn.Op == ONAME && sn.Class() != PEXTERN {
// Tell liveness we're about to build a new slice
s.vars[&memVar] = s.newValue1A(ssa.OpVarDef, types.TypeMem, sn, s.mem())
}
capaddr := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.IntPtr, sliceCapOffset, addr)
s.store(types.Types[TINT], capaddr, r[2])
s.store(pt, addr, r[0])
// load the value we just stored to avoid having to spill it
s.vars[&ptrVar] = s.load(pt, addr)
s.vars[&lenVar] = r[1] // avoid a spill in the fast path
} else {
s.vars[&ptrVar] = r[0]
s.vars[&newlenVar] = s.newValue2(s.ssaOp(OADD, types.Types[TINT]), types.Types[TINT], r[1], s.constInt(types.Types[TINT], nargs))
s.vars[&capVar] = r[2]
}
b = s.endBlock()
b.AddEdgeTo(assign)
// assign new elements to slots
s.startBlock(assign)
if inplace {
l = s.variable(&lenVar, types.Types[TINT]) // generates phi for len
nl = s.newValue2(s.ssaOp(OADD, types.Types[TINT]), types.Types[TINT], l, s.constInt(types.Types[TINT], nargs))
lenaddr := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.IntPtr, sliceLenOffset, addr)
s.store(types.Types[TINT], lenaddr, nl)
}
// Evaluate args
type argRec struct {
// if store is true, we're appending the value v. If false, we're appending the
// value at *v.
v *ssa.Value
store bool
}
args := make([]argRec, 0, nargs)
for _, n := range n.List.Slice()[1:] {
if canSSAType(n.Type) {
args = append(args, argRec{v: s.expr(n), store: true})
} else {
v := s.addr(n)
args = append(args, argRec{v: v})
}
}
p = s.variable(&ptrVar, pt) // generates phi for ptr
if !inplace {
nl = s.variable(&newlenVar, types.Types[TINT]) // generates phi for nl
c = s.variable(&capVar, types.Types[TINT]) // generates phi for cap
}
p2 := s.newValue2(ssa.OpPtrIndex, pt, p, l)
for i, arg := range args {
addr := s.newValue2(ssa.OpPtrIndex, pt, p2, s.constInt(types.Types[TINT], int64(i)))
if arg.store {
s.storeType(et, addr, arg.v, 0, true)
} else {
s.move(et, addr, arg.v)
}
}
delete(s.vars, &ptrVar)
if inplace {
delete(s.vars, &lenVar)
return nil
}
delete(s.vars, &newlenVar)
delete(s.vars, &capVar)
// make result
return s.newValue3(ssa.OpSliceMake, n.Type, p, nl, c)
}
// condBranch evaluates the boolean expression cond and branches to yes
// if cond is true and no if cond is false.
// This function is intended to handle && and || better than just calling
// s.expr(cond) and branching on the result.
func (s *state) condBranch(cond *Node, yes, no *ssa.Block, likely int8) {
switch cond.Op {
case OANDAND:
mid := s.f.NewBlock(ssa.BlockPlain)
s.stmtList(cond.Ninit)
s.condBranch(cond.Left, mid, no, max8(likely, 0))
s.startBlock(mid)
s.condBranch(cond.Right, yes, no, likely)
return
// Note: if likely==1, then both recursive calls pass 1.
// If likely==-1, then we don't have enough information to decide
// whether the first branch is likely or not. So we pass 0 for
// the likeliness of the first branch.
// TODO: have the frontend give us branch prediction hints for
// OANDAND and OOROR nodes (if it ever has such info).
case OOROR:
mid := s.f.NewBlock(ssa.BlockPlain)
s.stmtList(cond.Ninit)
s.condBranch(cond.Left, yes, mid, min8(likely, 0))
s.startBlock(mid)
s.condBranch(cond.Right, yes, no, likely)
return
// Note: if likely==-1, then both recursive calls pass -1.
// If likely==1, then we don't have enough info to decide
// the likelihood of the first branch.
case ONOT:
s.stmtList(cond.Ninit)
s.condBranch(cond.Left, no, yes, -likely)
return
}
c := s.expr(cond)
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(c)
b.Likely = ssa.BranchPrediction(likely) // gc and ssa both use -1/0/+1 for likeliness
b.AddEdgeTo(yes)
b.AddEdgeTo(no)
}
type skipMask uint8
const (
skipPtr skipMask = 1 << iota
skipLen
skipCap
)
// assign does left = right.
// Right has already been evaluated to ssa, left has not.
// If deref is true, then we do left = *right instead (and right has already been nil-checked).
// If deref is true and right == nil, just do left = 0.
// skip indicates assignments (at the top level) that can be avoided.
func (s *state) assign(left *Node, right *ssa.Value, deref bool, skip skipMask) {
if left.Op == ONAME && left.isBlank() {
return
}
t := left.Type
dowidth(t)
if s.canSSA(left) {
if deref {
s.Fatalf("can SSA LHS %v but not RHS %s", left, right)
}
if left.Op == ODOT {
// We're assigning to a field of an ssa-able value.
// We need to build a new structure with the new value for the
// field we're assigning and the old values for the other fields.
// For instance:
// type T struct {a, b, c int}
// var T x
// x.b = 5
// For the x.b = 5 assignment we want to generate x = T{x.a, 5, x.c}
// Grab information about the structure type.
t := left.Left.Type
nf := t.NumFields()
idx := fieldIdx(left)
// Grab old value of structure.
old := s.expr(left.Left)
// Make new structure.
new := s.newValue0(ssa.StructMakeOp(t.NumFields()), t)
// Add fields as args.
for i := 0; i < nf; i++ {
if i == idx {
new.AddArg(right)
} else {
new.AddArg(s.newValue1I(ssa.OpStructSelect, t.FieldType(i), int64(i), old))
}
}
// Recursively assign the new value we've made to the base of the dot op.
s.assign(left.Left, new, false, 0)
// TODO: do we need to update named values here?
return
}
if left.Op == OINDEX && left.Left.Type.IsArray() {
s.pushLine(left.Pos)
defer s.popLine()
// We're assigning to an element of an ssa-able array.
// a[i] = v
t := left.Left.Type
n := t.NumElem()
i := s.expr(left.Right) // index
if n == 0 {
// The bounds check must fail. Might as well
// ignore the actual index and just use zeros.
z := s.constInt(types.Types[TINT], 0)
s.boundsCheck(z, z, ssa.BoundsIndex, false)
return
}
if n != 1 {
s.Fatalf("assigning to non-1-length array")
}
// Rewrite to a = [1]{v}
len := s.constInt(types.Types[TINT], 1)
s.boundsCheck(i, len, ssa.BoundsIndex, false) // checks i == 0
v := s.newValue1(ssa.OpArrayMake1, t, right)
s.assign(left.Left, v, false, 0)
return
}
// Update variable assignment.
s.vars[left] = right
s.addNamedValue(left, right)
return
}
// If this assignment clobbers an entire local variable, then emit
// OpVarDef so liveness analysis knows the variable is redefined.
if base := clobberBase(left); base.Op == ONAME && base.Class() != PEXTERN && skip == 0 {
s.vars[&memVar] = s.newValue1Apos(ssa.OpVarDef, types.TypeMem, base, s.mem(), !base.IsAutoTmp())
}
// Left is not ssa-able. Compute its address.
addr := s.addr(left)
if isReflectHeaderDataField(left) {
// Package unsafe's documentation says storing pointers into
// reflect.SliceHeader and reflect.StringHeader's Data fields
// is valid, even though they have type uintptr (#19168).
// Mark it pointer type to signal the writebarrier pass to
// insert a write barrier.
t = types.Types[TUNSAFEPTR]
}
if deref {
// Treat as a mem->mem move.
if right == nil {
s.zero(t, addr)
} else {
s.move(t, addr, right)
}
return
}
// Treat as a store.
s.storeType(t, addr, right, skip, !left.IsAutoTmp())
}
// zeroVal returns the zero value for type t.
func (s *state) zeroVal(t *types.Type) *ssa.Value {
switch {
case t.IsInteger():
switch t.Size() {
case 1:
return s.constInt8(t, 0)
case 2:
return s.constInt16(t, 0)
case 4:
return s.constInt32(t, 0)
case 8:
return s.constInt64(t, 0)
default:
s.Fatalf("bad sized integer type %v", t)
}
case t.IsFloat():
switch t.Size() {
case 4:
return s.constFloat32(t, 0)
case 8:
return s.constFloat64(t, 0)
default:
s.Fatalf("bad sized float type %v", t)
}
case t.IsComplex():
switch t.Size() {
case 8:
z := s.constFloat32(types.Types[TFLOAT32], 0)
return s.entryNewValue2(ssa.OpComplexMake, t, z, z)
case 16:
z := s.constFloat64(types.Types[TFLOAT64], 0)
return s.entryNewValue2(ssa.OpComplexMake, t, z, z)
default:
s.Fatalf("bad sized complex type %v", t)
}
case t.IsString():
return s.constEmptyString(t)
case t.IsPtrShaped():
return s.constNil(t)
case t.IsBoolean():
return s.constBool(false)
case t.IsInterface():
return s.constInterface(t)
case t.IsSlice():
return s.constSlice(t)
case t.IsStruct():
n := t.NumFields()
v := s.entryNewValue0(ssa.StructMakeOp(t.NumFields()), t)
for i := 0; i < n; i++ {
v.AddArg(s.zeroVal(t.FieldType(i)))
}
return v
case t.IsArray():
switch t.NumElem() {
case 0:
return s.entryNewValue0(ssa.OpArrayMake0, t)
case 1:
return s.entryNewValue1(ssa.OpArrayMake1, t, s.zeroVal(t.Elem()))
}
}
s.Fatalf("zero for type %v not implemented", t)
return nil
}
type callKind int8
const (
callNormal callKind = iota
callDefer
callDeferStack
callGo
)
type sfRtCallDef struct {
rtfn *obj.LSym
rtype types.EType
}
var softFloatOps map[ssa.Op]sfRtCallDef
func softfloatInit() {
// Some of these operations get transformed by sfcall.
softFloatOps = map[ssa.Op]sfRtCallDef{
ssa.OpAdd32F: sfRtCallDef{sysfunc("fadd32"), TFLOAT32},
ssa.OpAdd64F: sfRtCallDef{sysfunc("fadd64"), TFLOAT64},
ssa.OpSub32F: sfRtCallDef{sysfunc("fadd32"), TFLOAT32},
ssa.OpSub64F: sfRtCallDef{sysfunc("fadd64"), TFLOAT64},
ssa.OpMul32F: sfRtCallDef{sysfunc("fmul32"), TFLOAT32},
ssa.OpMul64F: sfRtCallDef{sysfunc("fmul64"), TFLOAT64},
ssa.OpDiv32F: sfRtCallDef{sysfunc("fdiv32"), TFLOAT32},
ssa.OpDiv64F: sfRtCallDef{sysfunc("fdiv64"), TFLOAT64},
ssa.OpEq64F: sfRtCallDef{sysfunc("feq64"), TBOOL},
ssa.OpEq32F: sfRtCallDef{sysfunc("feq32"), TBOOL},
ssa.OpNeq64F: sfRtCallDef{sysfunc("feq64"), TBOOL},
ssa.OpNeq32F: sfRtCallDef{sysfunc("feq32"), TBOOL},
ssa.OpLess64F: sfRtCallDef{sysfunc("fgt64"), TBOOL},
ssa.OpLess32F: sfRtCallDef{sysfunc("fgt32"), TBOOL},
ssa.OpLeq64F: sfRtCallDef{sysfunc("fge64"), TBOOL},
ssa.OpLeq32F: sfRtCallDef{sysfunc("fge32"), TBOOL},
ssa.OpCvt32to32F: sfRtCallDef{sysfunc("fint32to32"), TFLOAT32},
ssa.OpCvt32Fto32: sfRtCallDef{sysfunc("f32toint32"), TINT32},
ssa.OpCvt64to32F: sfRtCallDef{sysfunc("fint64to32"), TFLOAT32},
ssa.OpCvt32Fto64: sfRtCallDef{sysfunc("f32toint64"), TINT64},
ssa.OpCvt64Uto32F: sfRtCallDef{sysfunc("fuint64to32"), TFLOAT32},
ssa.OpCvt32Fto64U: sfRtCallDef{sysfunc("f32touint64"), TUINT64},
ssa.OpCvt32to64F: sfRtCallDef{sysfunc("fint32to64"), TFLOAT64},
ssa.OpCvt64Fto32: sfRtCallDef{sysfunc("f64toint32"), TINT32},
ssa.OpCvt64to64F: sfRtCallDef{sysfunc("fint64to64"), TFLOAT64},
ssa.OpCvt64Fto64: sfRtCallDef{sysfunc("f64toint64"), TINT64},
ssa.OpCvt64Uto64F: sfRtCallDef{sysfunc("fuint64to64"), TFLOAT64},
ssa.OpCvt64Fto64U: sfRtCallDef{sysfunc("f64touint64"), TUINT64},
ssa.OpCvt32Fto64F: sfRtCallDef{sysfunc("f32to64"), TFLOAT64},
ssa.OpCvt64Fto32F: sfRtCallDef{sysfunc("f64to32"), TFLOAT32},
}
}
// TODO: do not emit sfcall if operation can be optimized to constant in later
// opt phase
func (s *state) sfcall(op ssa.Op, args ...*ssa.Value) (*ssa.Value, bool) {
if callDef, ok := softFloatOps[op]; ok {
switch op {
case ssa.OpLess32F,
ssa.OpLess64F,
ssa.OpLeq32F,
ssa.OpLeq64F:
args[0], args[1] = args[1], args[0]
case ssa.OpSub32F,
ssa.OpSub64F:
args[1] = s.newValue1(s.ssaOp(ONEG, types.Types[callDef.rtype]), args[1].Type, args[1])
}
result := s.rtcall(callDef.rtfn, true, []*types.Type{types.Types[callDef.rtype]}, args...)[0]
if op == ssa.OpNeq32F || op == ssa.OpNeq64F {
result = s.newValue1(ssa.OpNot, result.Type, result)
}
return result, true
}
return nil, false
}
var intrinsics map[intrinsicKey]intrinsicBuilder
// An intrinsicBuilder converts a call node n into an ssa value that
// implements that call as an intrinsic. args is a list of arguments to the func.
type intrinsicBuilder func(s *state, n *Node, args []*ssa.Value) *ssa.Value
type intrinsicKey struct {
arch *sys.Arch
pkg string
fn string
}
func init() {
intrinsics = map[intrinsicKey]intrinsicBuilder{}
var all []*sys.Arch
var p4 []*sys.Arch
var p8 []*sys.Arch
var lwatomics []*sys.Arch
for _, a := range &sys.Archs {
all = append(all, a)
if a.PtrSize == 4 {
p4 = append(p4, a)
} else {
p8 = append(p8, a)
}
if a.Family != sys.PPC64 {
lwatomics = append(lwatomics, a)
}
}
// add adds the intrinsic b for pkg.fn for the given list of architectures.
add := func(pkg, fn string, b intrinsicBuilder, archs ...*sys.Arch) {
for _, a := range archs {
intrinsics[intrinsicKey{a, pkg, fn}] = b
}
}
// addF does the same as add but operates on architecture families.
addF := func(pkg, fn string, b intrinsicBuilder, archFamilies ...sys.ArchFamily) {
m := 0
for _, f := range archFamilies {
if f >= 32 {
panic("too many architecture families")
}
m |= 1 << uint(f)
}
for _, a := range all {
if m>>uint(a.Family)&1 != 0 {
intrinsics[intrinsicKey{a, pkg, fn}] = b
}
}
}
// alias defines pkg.fn = pkg2.fn2 for all architectures in archs for which pkg2.fn2 exists.
alias := func(pkg, fn, pkg2, fn2 string, archs ...*sys.Arch) {
aliased := false
for _, a := range archs {
if b, ok := intrinsics[intrinsicKey{a, pkg2, fn2}]; ok {
intrinsics[intrinsicKey{a, pkg, fn}] = b
aliased = true
}
}
if !aliased {
panic(fmt.Sprintf("attempted to alias undefined intrinsic: %s.%s", pkg, fn))
}
}
/******** runtime ********/
if !instrumenting {
add("runtime", "slicebytetostringtmp",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
// Compiler frontend optimizations emit OBYTES2STRTMP nodes
// for the backend instead of slicebytetostringtmp calls
// when not instrumenting.
return s.newValue2(ssa.OpStringMake, n.Type, args[0], args[1])
},
all...)
}
addF("runtime/internal/math", "MulUintptr",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
if s.config.PtrSize == 4 {
return s.newValue2(ssa.OpMul32uover, types.NewTuple(types.Types[TUINT], types.Types[TUINT]), args[0], args[1])
}
return s.newValue2(ssa.OpMul64uover, types.NewTuple(types.Types[TUINT], types.Types[TUINT]), args[0], args[1])
},
sys.AMD64, sys.I386, sys.MIPS64)
add("runtime", "KeepAlive",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
data := s.newValue1(ssa.OpIData, s.f.Config.Types.BytePtr, args[0])
s.vars[&memVar] = s.newValue2(ssa.OpKeepAlive, types.TypeMem, data, s.mem())
return nil
},
all...)
add("runtime", "getclosureptr",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue0(ssa.OpGetClosurePtr, s.f.Config.Types.Uintptr)
},
all...)
add("runtime", "getcallerpc",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue0(ssa.OpGetCallerPC, s.f.Config.Types.Uintptr)
},
all...)
add("runtime", "getcallersp",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue0(ssa.OpGetCallerSP, s.f.Config.Types.Uintptr)
},
all...)
/******** runtime/internal/sys ********/
addF("runtime/internal/sys", "Ctz32",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpCtz32, types.Types[TINT], args[0])
},
sys.AMD64, sys.ARM64, sys.ARM, sys.S390X, sys.MIPS, sys.PPC64)
addF("runtime/internal/sys", "Ctz64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpCtz64, types.Types[TINT], args[0])
},
sys.AMD64, sys.ARM64, sys.ARM, sys.S390X, sys.MIPS, sys.PPC64)
addF("runtime/internal/sys", "Bswap32",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpBswap32, types.Types[TUINT32], args[0])
},
sys.AMD64, sys.ARM64, sys.ARM, sys.S390X)
addF("runtime/internal/sys", "Bswap64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpBswap64, types.Types[TUINT64], args[0])
},
sys.AMD64, sys.ARM64, sys.ARM, sys.S390X)
/******** runtime/internal/atomic ********/
addF("runtime/internal/atomic", "Load",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
v := s.newValue2(ssa.OpAtomicLoad32, types.NewTuple(types.Types[TUINT32], types.TypeMem), args[0], s.mem())
s.vars[&memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v)
return s.newValue1(ssa.OpSelect0, types.Types[TUINT32], v)
},
sys.AMD64, sys.ARM64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X)
addF("runtime/internal/atomic", "Load8",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
v := s.newValue2(ssa.OpAtomicLoad8, types.NewTuple(types.Types[TUINT8], types.TypeMem), args[0], s.mem())
s.vars[&memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v)
return s.newValue1(ssa.OpSelect0, types.Types[TUINT8], v)
},
sys.AMD64, sys.ARM64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X)
addF("runtime/internal/atomic", "Load64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
v := s.newValue2(ssa.OpAtomicLoad64, types.NewTuple(types.Types[TUINT64], types.TypeMem), args[0], s.mem())
s.vars[&memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v)
return s.newValue1(ssa.OpSelect0, types.Types[TUINT64], v)
},
sys.AMD64, sys.ARM64, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X)
addF("runtime/internal/atomic", "LoadAcq",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
v := s.newValue2(ssa.OpAtomicLoadAcq32, types.NewTuple(types.Types[TUINT32], types.TypeMem), args[0], s.mem())
s.vars[&memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v)
return s.newValue1(ssa.OpSelect0, types.Types[TUINT32], v)
},
sys.PPC64, sys.S390X)
addF("runtime/internal/atomic", "Loadp",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
v := s.newValue2(ssa.OpAtomicLoadPtr, types.NewTuple(s.f.Config.Types.BytePtr, types.TypeMem), args[0], s.mem())
s.vars[&memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v)
return s.newValue1(ssa.OpSelect0, s.f.Config.Types.BytePtr, v)
},
sys.AMD64, sys.ARM64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X)
addF("runtime/internal/atomic", "Store",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
s.vars[&memVar] = s.newValue3(ssa.OpAtomicStore32, types.TypeMem, args[0], args[1], s.mem())
return nil
},
sys.AMD64, sys.ARM64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X)
addF("runtime/internal/atomic", "Store8",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
s.vars[&memVar] = s.newValue3(ssa.OpAtomicStore8, types.TypeMem, args[0], args[1], s.mem())
return nil
},
sys.AMD64, sys.ARM64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X)
addF("runtime/internal/atomic", "Store64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
s.vars[&memVar] = s.newValue3(ssa.OpAtomicStore64, types.TypeMem, args[0], args[1], s.mem())
return nil
},
sys.AMD64, sys.ARM64, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X)
addF("runtime/internal/atomic", "StorepNoWB",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
s.vars[&memVar] = s.newValue3(ssa.OpAtomicStorePtrNoWB, types.TypeMem, args[0], args[1], s.mem())
return nil
},
sys.AMD64, sys.ARM64, sys.MIPS, sys.MIPS64, sys.RISCV64, sys.S390X)
addF("runtime/internal/atomic", "StoreRel",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
s.vars[&memVar] = s.newValue3(ssa.OpAtomicStoreRel32, types.TypeMem, args[0], args[1], s.mem())
return nil
},
sys.PPC64, sys.S390X)
addF("runtime/internal/atomic", "Xchg",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
v := s.newValue3(ssa.OpAtomicExchange32, types.NewTuple(types.Types[TUINT32], types.TypeMem), args[0], args[1], s.mem())
s.vars[&memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v)
return s.newValue1(ssa.OpSelect0, types.Types[TUINT32], v)
},
sys.AMD64, sys.ARM64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X)
addF("runtime/internal/atomic", "Xchg64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
v := s.newValue3(ssa.OpAtomicExchange64, types.NewTuple(types.Types[TUINT64], types.TypeMem), args[0], args[1], s.mem())
s.vars[&memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v)
return s.newValue1(ssa.OpSelect0, types.Types[TUINT64], v)
},
sys.AMD64, sys.ARM64, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X)
addF("runtime/internal/atomic", "Xadd",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
v := s.newValue3(ssa.OpAtomicAdd32, types.NewTuple(types.Types[TUINT32], types.TypeMem), args[0], args[1], s.mem())
s.vars[&memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v)
return s.newValue1(ssa.OpSelect0, types.Types[TUINT32], v)
},
sys.AMD64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X)
addF("runtime/internal/atomic", "Xadd64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
v := s.newValue3(ssa.OpAtomicAdd64, types.NewTuple(types.Types[TUINT64], types.TypeMem), args[0], args[1], s.mem())
s.vars[&memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v)
return s.newValue1(ssa.OpSelect0, types.Types[TUINT64], v)
},
sys.AMD64, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X)
makeXaddARM64 := func(op0 ssa.Op, op1 ssa.Op, ty types.EType) func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
// Target Atomic feature is identified by dynamic detection
addr := s.entryNewValue1A(ssa.OpAddr, types.Types[TBOOL].PtrTo(), arm64HasATOMICS, s.sb)
v := s.load(types.Types[TBOOL], addr)
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(v)
bTrue := s.f.NewBlock(ssa.BlockPlain)
bFalse := s.f.NewBlock(ssa.BlockPlain)
bEnd := s.f.NewBlock(ssa.BlockPlain)
b.AddEdgeTo(bTrue)
b.AddEdgeTo(bFalse)
b.Likely = ssa.BranchUnlikely // most machines don't have Atomics nowadays
// We have atomic instructions - use it directly.
s.startBlock(bTrue)
v0 := s.newValue3(op1, types.NewTuple(types.Types[ty], types.TypeMem), args[0], args[1], s.mem())
s.vars[&memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v0)
s.vars[n] = s.newValue1(ssa.OpSelect0, types.Types[ty], v0)
s.endBlock().AddEdgeTo(bEnd)
// Use original instruction sequence.
s.startBlock(bFalse)
v1 := s.newValue3(op0, types.NewTuple(types.Types[ty], types.TypeMem), args[0], args[1], s.mem())
s.vars[&memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v1)
s.vars[n] = s.newValue1(ssa.OpSelect0, types.Types[ty], v1)
s.endBlock().AddEdgeTo(bEnd)
// Merge results.
s.startBlock(bEnd)
return s.variable(n, types.Types[ty])
}
}
addF("runtime/internal/atomic", "Xadd",
makeXaddARM64(ssa.OpAtomicAdd32, ssa.OpAtomicAdd32Variant, TUINT32),
sys.ARM64)
addF("runtime/internal/atomic", "Xadd64",
makeXaddARM64(ssa.OpAtomicAdd64, ssa.OpAtomicAdd64Variant, TUINT64),
sys.ARM64)
addF("runtime/internal/atomic", "Cas",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
v := s.newValue4(ssa.OpAtomicCompareAndSwap32, types.NewTuple(types.Types[TBOOL], types.TypeMem), args[0], args[1], args[2], s.mem())
s.vars[&memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v)
return s.newValue1(ssa.OpSelect0, types.Types[TBOOL], v)
},
sys.AMD64, sys.ARM64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X)
addF("runtime/internal/atomic", "Cas64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
v := s.newValue4(ssa.OpAtomicCompareAndSwap64, types.NewTuple(types.Types[TBOOL], types.TypeMem), args[0], args[1], args[2], s.mem())
s.vars[&memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v)
return s.newValue1(ssa.OpSelect0, types.Types[TBOOL], v)
},
sys.AMD64, sys.ARM64, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X)
addF("runtime/internal/atomic", "CasRel",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
v := s.newValue4(ssa.OpAtomicCompareAndSwap32, types.NewTuple(types.Types[TBOOL], types.TypeMem), args[0], args[1], args[2], s.mem())
s.vars[&memVar] = s.newValue1(ssa.OpSelect1, types.TypeMem, v)
return s.newValue1(ssa.OpSelect0, types.Types[TBOOL], v)
},
sys.PPC64)
addF("runtime/internal/atomic", "And8",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
s.vars[&memVar] = s.newValue3(ssa.OpAtomicAnd8, types.TypeMem, args[0], args[1], s.mem())
return nil
},
sys.AMD64, sys.ARM64, sys.MIPS, sys.PPC64, sys.S390X)
addF("runtime/internal/atomic", "Or8",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
s.vars[&memVar] = s.newValue3(ssa.OpAtomicOr8, types.TypeMem, args[0], args[1], s.mem())
return nil
},
sys.AMD64, sys.ARM64, sys.MIPS, sys.PPC64, sys.S390X)
alias("runtime/internal/atomic", "Loadint64", "runtime/internal/atomic", "Load64", all...)
alias("runtime/internal/atomic", "Xaddint64", "runtime/internal/atomic", "Xadd64", all...)
alias("runtime/internal/atomic", "Loaduint", "runtime/internal/atomic", "Load", p4...)
alias("runtime/internal/atomic", "Loaduint", "runtime/internal/atomic", "Load64", p8...)
alias("runtime/internal/atomic", "Loaduintptr", "runtime/internal/atomic", "Load", p4...)
alias("runtime/internal/atomic", "Loaduintptr", "runtime/internal/atomic", "Load64", p8...)
alias("runtime/internal/atomic", "LoadAcq", "runtime/internal/atomic", "Load", lwatomics...)
alias("runtime/internal/atomic", "Storeuintptr", "runtime/internal/atomic", "Store", p4...)
alias("runtime/internal/atomic", "Storeuintptr", "runtime/internal/atomic", "Store64", p8...)
alias("runtime/internal/atomic", "StoreRel", "runtime/internal/atomic", "Store", lwatomics...)
alias("runtime/internal/atomic", "Xchguintptr", "runtime/internal/atomic", "Xchg", p4...)
alias("runtime/internal/atomic", "Xchguintptr", "runtime/internal/atomic", "Xchg64", p8...)
alias("runtime/internal/atomic", "Xadduintptr", "runtime/internal/atomic", "Xadd", p4...)
alias("runtime/internal/atomic", "Xadduintptr", "runtime/internal/atomic", "Xadd64", p8...)
alias("runtime/internal/atomic", "Casuintptr", "runtime/internal/atomic", "Cas", p4...)
alias("runtime/internal/atomic", "Casuintptr", "runtime/internal/atomic", "Cas64", p8...)
alias("runtime/internal/atomic", "Casp1", "runtime/internal/atomic", "Cas", p4...)
alias("runtime/internal/atomic", "Casp1", "runtime/internal/atomic", "Cas64", p8...)
alias("runtime/internal/atomic", "CasRel", "runtime/internal/atomic", "Cas", lwatomics...)
/******** math ********/
addF("math", "Sqrt",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpSqrt, types.Types[TFLOAT64], args[0])
},
sys.I386, sys.AMD64, sys.ARM, sys.ARM64, sys.MIPS, sys.MIPS64, sys.PPC64, sys.RISCV64, sys.S390X, sys.Wasm)
addF("math", "Trunc",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpTrunc, types.Types[TFLOAT64], args[0])
},
sys.ARM64, sys.PPC64, sys.S390X, sys.Wasm)
addF("math", "Ceil",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpCeil, types.Types[TFLOAT64], args[0])
},
sys.ARM64, sys.PPC64, sys.S390X, sys.Wasm)
addF("math", "Floor",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpFloor, types.Types[TFLOAT64], args[0])
},
sys.ARM64, sys.PPC64, sys.S390X, sys.Wasm)
addF("math", "Round",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpRound, types.Types[TFLOAT64], args[0])
},
sys.ARM64, sys.PPC64, sys.S390X)
addF("math", "RoundToEven",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpRoundToEven, types.Types[TFLOAT64], args[0])
},
sys.ARM64, sys.S390X, sys.Wasm)
addF("math", "Abs",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpAbs, types.Types[TFLOAT64], args[0])
},
sys.ARM64, sys.ARM, sys.PPC64, sys.Wasm)
addF("math", "Copysign",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue2(ssa.OpCopysign, types.Types[TFLOAT64], args[0], args[1])
},
sys.PPC64, sys.Wasm)
addF("math", "FMA",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue3(ssa.OpFMA, types.Types[TFLOAT64], args[0], args[1], args[2])
},
sys.ARM64, sys.PPC64, sys.S390X)
addF("math", "FMA",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
if !s.config.UseFMA {
a := s.call(n, callNormal)
s.vars[n] = s.load(types.Types[TFLOAT64], a)
return s.variable(n, types.Types[TFLOAT64])
}
v := s.entryNewValue0A(ssa.OpHasCPUFeature, types.Types[TBOOL], x86HasFMA)
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(v)
bTrue := s.f.NewBlock(ssa.BlockPlain)
bFalse := s.f.NewBlock(ssa.BlockPlain)
bEnd := s.f.NewBlock(ssa.BlockPlain)
b.AddEdgeTo(bTrue)
b.AddEdgeTo(bFalse)
b.Likely = ssa.BranchLikely // >= haswell cpus are common
// We have the intrinsic - use it directly.
s.startBlock(bTrue)
s.vars[n] = s.newValue3(ssa.OpFMA, types.Types[TFLOAT64], args[0], args[1], args[2])
s.endBlock().AddEdgeTo(bEnd)
// Call the pure Go version.
s.startBlock(bFalse)
a := s.call(n, callNormal)
s.vars[n] = s.load(types.Types[TFLOAT64], a)
s.endBlock().AddEdgeTo(bEnd)
// Merge results.
s.startBlock(bEnd)
return s.variable(n, types.Types[TFLOAT64])
},
sys.AMD64)
addF("math", "FMA",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
if !s.config.UseFMA {
a := s.call(n, callNormal)
s.vars[n] = s.load(types.Types[TFLOAT64], a)
return s.variable(n, types.Types[TFLOAT64])
}
addr := s.entryNewValue1A(ssa.OpAddr, types.Types[TBOOL].PtrTo(), armHasVFPv4, s.sb)
v := s.load(types.Types[TBOOL], addr)
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(v)
bTrue := s.f.NewBlock(ssa.BlockPlain)
bFalse := s.f.NewBlock(ssa.BlockPlain)
bEnd := s.f.NewBlock(ssa.BlockPlain)
b.AddEdgeTo(bTrue)
b.AddEdgeTo(bFalse)
b.Likely = ssa.BranchLikely
// We have the intrinsic - use it directly.
s.startBlock(bTrue)
s.vars[n] = s.newValue3(ssa.OpFMA, types.Types[TFLOAT64], args[0], args[1], args[2])
s.endBlock().AddEdgeTo(bEnd)
// Call the pure Go version.
s.startBlock(bFalse)
a := s.call(n, callNormal)
s.vars[n] = s.load(types.Types[TFLOAT64], a)
s.endBlock().AddEdgeTo(bEnd)
// Merge results.
s.startBlock(bEnd)
return s.variable(n, types.Types[TFLOAT64])
},
sys.ARM)
makeRoundAMD64 := func(op ssa.Op) func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
v := s.entryNewValue0A(ssa.OpHasCPUFeature, types.Types[TBOOL], x86HasSSE41)
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(v)
bTrue := s.f.NewBlock(ssa.BlockPlain)
bFalse := s.f.NewBlock(ssa.BlockPlain)
bEnd := s.f.NewBlock(ssa.BlockPlain)
b.AddEdgeTo(bTrue)
b.AddEdgeTo(bFalse)
b.Likely = ssa.BranchLikely // most machines have sse4.1 nowadays
// We have the intrinsic - use it directly.
s.startBlock(bTrue)
s.vars[n] = s.newValue1(op, types.Types[TFLOAT64], args[0])
s.endBlock().AddEdgeTo(bEnd)
// Call the pure Go version.
s.startBlock(bFalse)
a := s.call(n, callNormal)
s.vars[n] = s.load(types.Types[TFLOAT64], a)
s.endBlock().AddEdgeTo(bEnd)
// Merge results.
s.startBlock(bEnd)
return s.variable(n, types.Types[TFLOAT64])
}
}
addF("math", "RoundToEven",
makeRoundAMD64(ssa.OpRoundToEven),
sys.AMD64)
addF("math", "Floor",
makeRoundAMD64(ssa.OpFloor),
sys.AMD64)
addF("math", "Ceil",
makeRoundAMD64(ssa.OpCeil),
sys.AMD64)
addF("math", "Trunc",
makeRoundAMD64(ssa.OpTrunc),
sys.AMD64)
/******** math/bits ********/
addF("math/bits", "TrailingZeros64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpCtz64, types.Types[TINT], args[0])
},
sys.AMD64, sys.ARM64, sys.ARM, sys.S390X, sys.MIPS, sys.PPC64, sys.Wasm)
addF("math/bits", "TrailingZeros32",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpCtz32, types.Types[TINT], args[0])
},
sys.AMD64, sys.ARM64, sys.ARM, sys.S390X, sys.MIPS, sys.PPC64, sys.Wasm)
addF("math/bits", "TrailingZeros16",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
x := s.newValue1(ssa.OpZeroExt16to32, types.Types[TUINT32], args[0])
c := s.constInt32(types.Types[TUINT32], 1<<16)
y := s.newValue2(ssa.OpOr32, types.Types[TUINT32], x, c)
return s.newValue1(ssa.OpCtz32, types.Types[TINT], y)
},
sys.MIPS)
addF("math/bits", "TrailingZeros16",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpCtz16, types.Types[TINT], args[0])
},
sys.AMD64, sys.I386, sys.ARM, sys.ARM64, sys.Wasm)
addF("math/bits", "TrailingZeros16",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
x := s.newValue1(ssa.OpZeroExt16to64, types.Types[TUINT64], args[0])
c := s.constInt64(types.Types[TUINT64], 1<<16)
y := s.newValue2(ssa.OpOr64, types.Types[TUINT64], x, c)
return s.newValue1(ssa.OpCtz64, types.Types[TINT], y)
},
sys.S390X, sys.PPC64)
addF("math/bits", "TrailingZeros8",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
x := s.newValue1(ssa.OpZeroExt8to32, types.Types[TUINT32], args[0])
c := s.constInt32(types.Types[TUINT32], 1<<8)
y := s.newValue2(ssa.OpOr32, types.Types[TUINT32], x, c)
return s.newValue1(ssa.OpCtz32, types.Types[TINT], y)
},
sys.MIPS)
addF("math/bits", "TrailingZeros8",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpCtz8, types.Types[TINT], args[0])
},
sys.AMD64, sys.ARM, sys.ARM64, sys.Wasm)
addF("math/bits", "TrailingZeros8",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
x := s.newValue1(ssa.OpZeroExt8to64, types.Types[TUINT64], args[0])
c := s.constInt64(types.Types[TUINT64], 1<<8)
y := s.newValue2(ssa.OpOr64, types.Types[TUINT64], x, c)
return s.newValue1(ssa.OpCtz64, types.Types[TINT], y)
},
sys.S390X)
alias("math/bits", "ReverseBytes64", "runtime/internal/sys", "Bswap64", all...)
alias("math/bits", "ReverseBytes32", "runtime/internal/sys", "Bswap32", all...)
// ReverseBytes inlines correctly, no need to intrinsify it.
// ReverseBytes16 lowers to a rotate, no need for anything special here.
addF("math/bits", "Len64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpBitLen64, types.Types[TINT], args[0])
},
sys.AMD64, sys.ARM64, sys.ARM, sys.S390X, sys.MIPS, sys.PPC64, sys.Wasm)
addF("math/bits", "Len32",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpBitLen32, types.Types[TINT], args[0])
},
sys.AMD64, sys.ARM64)
addF("math/bits", "Len32",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
if s.config.PtrSize == 4 {
return s.newValue1(ssa.OpBitLen32, types.Types[TINT], args[0])
}
x := s.newValue1(ssa.OpZeroExt32to64, types.Types[TUINT64], args[0])
return s.newValue1(ssa.OpBitLen64, types.Types[TINT], x)
},
sys.ARM, sys.S390X, sys.MIPS, sys.PPC64, sys.Wasm)
addF("math/bits", "Len16",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
if s.config.PtrSize == 4 {
x := s.newValue1(ssa.OpZeroExt16to32, types.Types[TUINT32], args[0])
return s.newValue1(ssa.OpBitLen32, types.Types[TINT], x)
}
x := s.newValue1(ssa.OpZeroExt16to64, types.Types[TUINT64], args[0])
return s.newValue1(ssa.OpBitLen64, types.Types[TINT], x)
},
sys.ARM64, sys.ARM, sys.S390X, sys.MIPS, sys.PPC64, sys.Wasm)
addF("math/bits", "Len16",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpBitLen16, types.Types[TINT], args[0])
},
sys.AMD64)
addF("math/bits", "Len8",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
if s.config.PtrSize == 4 {
x := s.newValue1(ssa.OpZeroExt8to32, types.Types[TUINT32], args[0])
return s.newValue1(ssa.OpBitLen32, types.Types[TINT], x)
}
x := s.newValue1(ssa.OpZeroExt8to64, types.Types[TUINT64], args[0])
return s.newValue1(ssa.OpBitLen64, types.Types[TINT], x)
},
sys.ARM64, sys.ARM, sys.S390X, sys.MIPS, sys.PPC64, sys.Wasm)
addF("math/bits", "Len8",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpBitLen8, types.Types[TINT], args[0])
},
sys.AMD64)
addF("math/bits", "Len",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
if s.config.PtrSize == 4 {
return s.newValue1(ssa.OpBitLen32, types.Types[TINT], args[0])
}
return s.newValue1(ssa.OpBitLen64, types.Types[TINT], args[0])
},
sys.AMD64, sys.ARM64, sys.ARM, sys.S390X, sys.MIPS, sys.PPC64, sys.Wasm)
// LeadingZeros is handled because it trivially calls Len.
addF("math/bits", "Reverse64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpBitRev64, types.Types[TINT], args[0])
},
sys.ARM64)
addF("math/bits", "Reverse32",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpBitRev32, types.Types[TINT], args[0])
},
sys.ARM64)
addF("math/bits", "Reverse16",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpBitRev16, types.Types[TINT], args[0])
},
sys.ARM64)
addF("math/bits", "Reverse8",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpBitRev8, types.Types[TINT], args[0])
},
sys.ARM64)
addF("math/bits", "Reverse",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
if s.config.PtrSize == 4 {
return s.newValue1(ssa.OpBitRev32, types.Types[TINT], args[0])
}
return s.newValue1(ssa.OpBitRev64, types.Types[TINT], args[0])
},
sys.ARM64)
addF("math/bits", "RotateLeft8",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue2(ssa.OpRotateLeft8, types.Types[TUINT8], args[0], args[1])
},
sys.AMD64)
addF("math/bits", "RotateLeft16",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue2(ssa.OpRotateLeft16, types.Types[TUINT16], args[0], args[1])
},
sys.AMD64)
addF("math/bits", "RotateLeft32",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue2(ssa.OpRotateLeft32, types.Types[TUINT32], args[0], args[1])
},
sys.AMD64, sys.ARM, sys.ARM64, sys.S390X, sys.PPC64, sys.Wasm)
addF("math/bits", "RotateLeft64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue2(ssa.OpRotateLeft64, types.Types[TUINT64], args[0], args[1])
},
sys.AMD64, sys.ARM64, sys.S390X, sys.PPC64, sys.Wasm)
alias("math/bits", "RotateLeft", "math/bits", "RotateLeft64", p8...)
makeOnesCountAMD64 := func(op64 ssa.Op, op32 ssa.Op) func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
v := s.entryNewValue0A(ssa.OpHasCPUFeature, types.Types[TBOOL], x86HasPOPCNT)
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(v)
bTrue := s.f.NewBlock(ssa.BlockPlain)
bFalse := s.f.NewBlock(ssa.BlockPlain)
bEnd := s.f.NewBlock(ssa.BlockPlain)
b.AddEdgeTo(bTrue)
b.AddEdgeTo(bFalse)
b.Likely = ssa.BranchLikely // most machines have popcnt nowadays
// We have the intrinsic - use it directly.
s.startBlock(bTrue)
op := op64
if s.config.PtrSize == 4 {
op = op32
}
s.vars[n] = s.newValue1(op, types.Types[TINT], args[0])
s.endBlock().AddEdgeTo(bEnd)
// Call the pure Go version.
s.startBlock(bFalse)
a := s.call(n, callNormal)
s.vars[n] = s.load(types.Types[TINT], a)
s.endBlock().AddEdgeTo(bEnd)
// Merge results.
s.startBlock(bEnd)
return s.variable(n, types.Types[TINT])
}
}
addF("math/bits", "OnesCount64",
makeOnesCountAMD64(ssa.OpPopCount64, ssa.OpPopCount64),
sys.AMD64)
addF("math/bits", "OnesCount64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpPopCount64, types.Types[TINT], args[0])
},
sys.PPC64, sys.ARM64, sys.S390X, sys.Wasm)
addF("math/bits", "OnesCount32",
makeOnesCountAMD64(ssa.OpPopCount32, ssa.OpPopCount32),
sys.AMD64)
addF("math/bits", "OnesCount32",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpPopCount32, types.Types[TINT], args[0])
},
sys.PPC64, sys.ARM64, sys.S390X, sys.Wasm)
addF("math/bits", "OnesCount16",
makeOnesCountAMD64(ssa.OpPopCount16, ssa.OpPopCount16),
sys.AMD64)
addF("math/bits", "OnesCount16",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpPopCount16, types.Types[TINT], args[0])
},
sys.ARM64, sys.S390X, sys.PPC64, sys.Wasm)
addF("math/bits", "OnesCount8",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue1(ssa.OpPopCount8, types.Types[TINT], args[0])
},
sys.S390X, sys.PPC64, sys.Wasm)
addF("math/bits", "OnesCount",
makeOnesCountAMD64(ssa.OpPopCount64, ssa.OpPopCount32),
sys.AMD64)
addF("math/bits", "Mul64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue2(ssa.OpMul64uhilo, types.NewTuple(types.Types[TUINT64], types.Types[TUINT64]), args[0], args[1])
},
sys.AMD64, sys.ARM64, sys.PPC64, sys.S390X, sys.MIPS64)
alias("math/bits", "Mul", "math/bits", "Mul64", sys.ArchAMD64, sys.ArchARM64, sys.ArchPPC64, sys.ArchS390X, sys.ArchMIPS64, sys.ArchMIPS64LE)
addF("math/bits", "Add64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue3(ssa.OpAdd64carry, types.NewTuple(types.Types[TUINT64], types.Types[TUINT64]), args[0], args[1], args[2])
},
sys.AMD64, sys.ARM64, sys.PPC64, sys.S390X)
alias("math/bits", "Add", "math/bits", "Add64", sys.ArchAMD64, sys.ArchARM64, sys.ArchPPC64, sys.ArchS390X)
addF("math/bits", "Sub64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue3(ssa.OpSub64borrow, types.NewTuple(types.Types[TUINT64], types.Types[TUINT64]), args[0], args[1], args[2])
},
sys.AMD64, sys.ARM64, sys.S390X)
alias("math/bits", "Sub", "math/bits", "Sub64", sys.ArchAMD64, sys.ArchARM64, sys.ArchS390X)
addF("math/bits", "Div64",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
// check for divide-by-zero/overflow and panic with appropriate message
cmpZero := s.newValue2(s.ssaOp(ONE, types.Types[TUINT64]), types.Types[TBOOL], args[2], s.zeroVal(types.Types[TUINT64]))
s.check(cmpZero, panicdivide)
cmpOverflow := s.newValue2(s.ssaOp(OLT, types.Types[TUINT64]), types.Types[TBOOL], args[0], args[2])
s.check(cmpOverflow, panicoverflow)
return s.newValue3(ssa.OpDiv128u, types.NewTuple(types.Types[TUINT64], types.Types[TUINT64]), args[0], args[1], args[2])
},
sys.AMD64)
alias("math/bits", "Div", "math/bits", "Div64", sys.ArchAMD64)
alias("runtime/internal/sys", "Ctz8", "math/bits", "TrailingZeros8", all...)
alias("runtime/internal/sys", "TrailingZeros8", "math/bits", "TrailingZeros8", all...)
alias("runtime/internal/sys", "TrailingZeros64", "math/bits", "TrailingZeros64", all...)
alias("runtime/internal/sys", "Len8", "math/bits", "Len8", all...)
alias("runtime/internal/sys", "Len64", "math/bits", "Len64", all...)
alias("runtime/internal/sys", "OnesCount64", "math/bits", "OnesCount64", all...)
/******** sync/atomic ********/
// Note: these are disabled by flag_race in findIntrinsic below.
alias("sync/atomic", "LoadInt32", "runtime/internal/atomic", "Load", all...)
alias("sync/atomic", "LoadInt64", "runtime/internal/atomic", "Load64", all...)
alias("sync/atomic", "LoadPointer", "runtime/internal/atomic", "Loadp", all...)
alias("sync/atomic", "LoadUint32", "runtime/internal/atomic", "Load", all...)
alias("sync/atomic", "LoadUint64", "runtime/internal/atomic", "Load64", all...)
alias("sync/atomic", "LoadUintptr", "runtime/internal/atomic", "Load", p4...)
alias("sync/atomic", "LoadUintptr", "runtime/internal/atomic", "Load64", p8...)
alias("sync/atomic", "StoreInt32", "runtime/internal/atomic", "Store", all...)
alias("sync/atomic", "StoreInt64", "runtime/internal/atomic", "Store64", all...)
// Note: not StorePointer, that needs a write barrier. Same below for {CompareAnd}Swap.
alias("sync/atomic", "StoreUint32", "runtime/internal/atomic", "Store", all...)
alias("sync/atomic", "StoreUint64", "runtime/internal/atomic", "Store64", all...)
alias("sync/atomic", "StoreUintptr", "runtime/internal/atomic", "Store", p4...)
alias("sync/atomic", "StoreUintptr", "runtime/internal/atomic", "Store64", p8...)
alias("sync/atomic", "SwapInt32", "runtime/internal/atomic", "Xchg", all...)
alias("sync/atomic", "SwapInt64", "runtime/internal/atomic", "Xchg64", all...)
alias("sync/atomic", "SwapUint32", "runtime/internal/atomic", "Xchg", all...)
alias("sync/atomic", "SwapUint64", "runtime/internal/atomic", "Xchg64", all...)
alias("sync/atomic", "SwapUintptr", "runtime/internal/atomic", "Xchg", p4...)
alias("sync/atomic", "SwapUintptr", "runtime/internal/atomic", "Xchg64", p8...)
alias("sync/atomic", "CompareAndSwapInt32", "runtime/internal/atomic", "Cas", all...)
alias("sync/atomic", "CompareAndSwapInt64", "runtime/internal/atomic", "Cas64", all...)
alias("sync/atomic", "CompareAndSwapUint32", "runtime/internal/atomic", "Cas", all...)
alias("sync/atomic", "CompareAndSwapUint64", "runtime/internal/atomic", "Cas64", all...)
alias("sync/atomic", "CompareAndSwapUintptr", "runtime/internal/atomic", "Cas", p4...)
alias("sync/atomic", "CompareAndSwapUintptr", "runtime/internal/atomic", "Cas64", p8...)
alias("sync/atomic", "AddInt32", "runtime/internal/atomic", "Xadd", all...)
alias("sync/atomic", "AddInt64", "runtime/internal/atomic", "Xadd64", all...)
alias("sync/atomic", "AddUint32", "runtime/internal/atomic", "Xadd", all...)
alias("sync/atomic", "AddUint64", "runtime/internal/atomic", "Xadd64", all...)
alias("sync/atomic", "AddUintptr", "runtime/internal/atomic", "Xadd", p4...)
alias("sync/atomic", "AddUintptr", "runtime/internal/atomic", "Xadd64", p8...)
/******** math/big ********/
add("math/big", "mulWW",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue2(ssa.OpMul64uhilo, types.NewTuple(types.Types[TUINT64], types.Types[TUINT64]), args[0], args[1])
},
sys.ArchAMD64, sys.ArchARM64, sys.ArchPPC64LE, sys.ArchPPC64, sys.ArchS390X)
add("math/big", "divWW",
func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
return s.newValue3(ssa.OpDiv128u, types.NewTuple(types.Types[TUINT64], types.Types[TUINT64]), args[0], args[1], args[2])
},
sys.ArchAMD64)
}
// findIntrinsic returns a function which builds the SSA equivalent of the
// function identified by the symbol sym. If sym is not an intrinsic call, returns nil.
func findIntrinsic(sym *types.Sym) intrinsicBuilder {
if sym == nil || sym.Pkg == nil {
return nil
}
pkg := sym.Pkg.Path
if sym.Pkg == localpkg {
pkg = myimportpath
}
if flag_race && pkg == "sync/atomic" {
// The race detector needs to be able to intercept these calls.
// We can't intrinsify them.
return nil
}
// Skip intrinsifying math functions (which may contain hard-float
// instructions) when soft-float
if thearch.SoftFloat && pkg == "math" {
return nil
}
fn := sym.Name
if ssa.IntrinsicsDisable {
if pkg == "runtime" && (fn == "getcallerpc" || fn == "getcallersp" || fn == "getclosureptr") {
// These runtime functions don't have definitions, must be intrinsics.
} else {
return nil
}
}
return intrinsics[intrinsicKey{thearch.LinkArch.Arch, pkg, fn}]
}
func isIntrinsicCall(n *Node) bool {
if n == nil || n.Left == nil {
return false
}
return findIntrinsic(n.Left.Sym) != nil
}
// intrinsicCall converts a call to a recognized intrinsic function into the intrinsic SSA operation.
func (s *state) intrinsicCall(n *Node) *ssa.Value {
v := findIntrinsic(n.Left.Sym)(s, n, s.intrinsicArgs(n))
if ssa.IntrinsicsDebug > 0 {
x := v
if x == nil {
x = s.mem()
}
if x.Op == ssa.OpSelect0 || x.Op == ssa.OpSelect1 {
x = x.Args[0]
}
Warnl(n.Pos, "intrinsic substitution for %v with %s", n.Left.Sym.Name, x.LongString())
}
return v
}
// intrinsicArgs extracts args from n, evaluates them to SSA values, and returns them.
func (s *state) intrinsicArgs(n *Node) []*ssa.Value {
// Construct map of temps; see comments in s.call about the structure of n.
temps := map[*Node]*ssa.Value{}
for _, a := range n.List.Slice() {
if a.Op != OAS {
s.Fatalf("non-assignment as a temp function argument %v", a.Op)
}
l, r := a.Left, a.Right
if l.Op != ONAME {
s.Fatalf("non-ONAME temp function argument %v", a.Op)
}
// Evaluate and store to "temporary".
// Walk ensures these temporaries are dead outside of n.
temps[l] = s.expr(r)
}
args := make([]*ssa.Value, n.Rlist.Len())
for i, n := range n.Rlist.Slice() {
// Store a value to an argument slot.
if x, ok := temps[n]; ok {
// This is a previously computed temporary.
args[i] = x
continue
}
// This is an explicit value; evaluate it.
args[i] = s.expr(n)
}
return args
}
// openDeferRecord adds code to evaluate and store the args for an open-code defer
// call, and records info about the defer, so we can generate proper code on the
// exit paths. n is the sub-node of the defer node that is the actual function
// call. We will also record funcdata information on where the args are stored
// (as well as the deferBits variable), and this will enable us to run the proper
// defer calls during panics.
func (s *state) openDeferRecord(n *Node) {
// Do any needed expression evaluation for the args (including the
// receiver, if any). This may be evaluating something like 'autotmp_3 =
// once.mutex'. Such a statement will create a mapping in s.vars[] from
// the autotmp name to the evaluated SSA arg value, but won't do any
// stores to the stack.
s.stmtList(n.List)
var args []*ssa.Value
var argNodes []*Node
opendefer := &openDeferInfo{
n: n,
}
fn := n.Left
if n.Op == OCALLFUNC {
// We must always store the function value in a stack slot for the
// runtime panic code to use. But in the defer exit code, we will
// call the function directly if it is a static function.
closureVal := s.expr(fn)
closure := s.openDeferSave(nil, fn.Type, closureVal)
opendefer.closureNode = closure.Aux.(*Node)
if !(fn.Op == ONAME && fn.Class() == PFUNC) {
opendefer.closure = closure
}
} else if n.Op == OCALLMETH {
if fn.Op != ODOTMETH {
Fatalf("OCALLMETH: n.Left not an ODOTMETH: %v", fn)
}
closureVal := s.getMethodClosure(fn)
// We must always store the function value in a stack slot for the
// runtime panic code to use. But in the defer exit code, we will
// call the method directly.
closure := s.openDeferSave(nil, fn.Type, closureVal)
opendefer.closureNode = closure.Aux.(*Node)
} else {
if fn.Op != ODOTINTER {
Fatalf("OCALLINTER: n.Left not an ODOTINTER: %v", fn.Op)
}
closure, rcvr := s.getClosureAndRcvr(fn)
opendefer.closure = s.openDeferSave(nil, closure.Type, closure)
// Important to get the receiver type correct, so it is recognized
// as a pointer for GC purposes.
opendefer.rcvr = s.openDeferSave(nil, fn.Type.Recv().Type, rcvr)
opendefer.closureNode = opendefer.closure.Aux.(*Node)
opendefer.rcvrNode = opendefer.rcvr.Aux.(*Node)
}
for _, argn := range n.Rlist.Slice() {
var v *ssa.Value
if canSSAType(argn.Type) {
v = s.openDeferSave(nil, argn.Type, s.expr(argn))
} else {
v = s.openDeferSave(argn, argn.Type, nil)
}
args = append(args, v)
argNodes = append(argNodes, v.Aux.(*Node))
}
opendefer.argVals = args
opendefer.argNodes = argNodes
index := len(s.openDefers)
s.openDefers = append(s.openDefers, opendefer)
// Update deferBits only after evaluation and storage to stack of
// args/receiver/interface is successful.
bitvalue := s.constInt8(types.Types[TUINT8], 1<<uint(index))
newDeferBits := s.newValue2(ssa.OpOr8, types.Types[TUINT8], s.variable(&deferBitsVar, types.Types[TUINT8]), bitvalue)
s.vars[&deferBitsVar] = newDeferBits
s.store(types.Types[TUINT8], s.deferBitsAddr, newDeferBits)
}
// openDeferSave generates SSA nodes to store a value (with type t) for an
// open-coded defer at an explicit autotmp location on the stack, so it can be
// reloaded and used for the appropriate call on exit. If type t is SSAable, then
// val must be non-nil (and n should be nil) and val is the value to be stored. If
// type t is non-SSAable, then n must be non-nil (and val should be nil) and n is
// evaluated (via s.addr() below) to get the value that is to be stored. The
// function returns an SSA value representing a pointer to the autotmp location.
func (s *state) openDeferSave(n *Node, t *types.Type, val *ssa.Value) *ssa.Value {
canSSA := canSSAType(t)
var pos src.XPos
if canSSA {
pos = val.Pos
} else {
pos = n.Pos
}
argTemp := tempAt(pos.WithNotStmt(), s.curfn, t)
argTemp.Name.SetOpenDeferSlot(true)
var addrArgTemp *ssa.Value
// Use OpVarLive to make sure stack slots for the args, etc. are not
// removed by dead-store elimination
if s.curBlock.ID != s.f.Entry.ID {
// Force the argtmp storing this defer function/receiver/arg to be
// declared in the entry block, so that it will be live for the
// defer exit code (which will actually access it only if the
// associated defer call has been activated).
s.defvars[s.f.Entry.ID][&memVar] = s.entryNewValue1A(ssa.OpVarDef, types.TypeMem, argTemp, s.defvars[s.f.Entry.ID][&memVar])
s.defvars[s.f.Entry.ID][&memVar] = s.entryNewValue1A(ssa.OpVarLive, types.TypeMem, argTemp, s.defvars[s.f.Entry.ID][&memVar])
addrArgTemp = s.entryNewValue2A(ssa.OpLocalAddr, types.NewPtr(argTemp.Type), argTemp, s.sp, s.defvars[s.f.Entry.ID][&memVar])
} else {
// Special case if we're still in the entry block. We can't use
// the above code, since s.defvars[s.f.Entry.ID] isn't defined
// until we end the entry block with s.endBlock().
s.vars[&memVar] = s.newValue1Apos(ssa.OpVarDef, types.TypeMem, argTemp, s.mem(), false)
s.vars[&memVar] = s.newValue1Apos(ssa.OpVarLive, types.TypeMem, argTemp, s.mem(), false)
addrArgTemp = s.newValue2Apos(ssa.OpLocalAddr, types.NewPtr(argTemp.Type), argTemp, s.sp, s.mem(), false)
}
if types.Haspointers(t) {
// Since we may use this argTemp during exit depending on the
// deferBits, we must define it unconditionally on entry.
// Therefore, we must make sure it is zeroed out in the entry
// block if it contains pointers, else GC may wrongly follow an
// uninitialized pointer value.
argTemp.Name.SetNeedzero(true)
}
if !canSSA {
a := s.addr(n)
s.move(t, addrArgTemp, a)
return addrArgTemp
}
// We are storing to the stack, hence we can avoid the full checks in
// storeType() (no write barrier) and do a simple store().
s.store(t, addrArgTemp, val)
return addrArgTemp
}
// openDeferExit generates SSA for processing all the open coded defers at exit.
// The code involves loading deferBits, and checking each of the bits to see if
// the corresponding defer statement was executed. For each bit that is turned
// on, the associated defer call is made.
func (s *state) openDeferExit() {
deferExit := s.f.NewBlock(ssa.BlockPlain)
s.endBlock().AddEdgeTo(deferExit)
s.startBlock(deferExit)
s.lastDeferExit = deferExit
s.lastDeferCount = len(s.openDefers)
zeroval := s.constInt8(types.Types[TUINT8], 0)
// Test for and run defers in reverse order
for i := len(s.openDefers) - 1; i >= 0; i-- {
r := s.openDefers[i]
bCond := s.f.NewBlock(ssa.BlockPlain)
bEnd := s.f.NewBlock(ssa.BlockPlain)
deferBits := s.variable(&deferBitsVar, types.Types[TUINT8])
// Generate code to check if the bit associated with the current
// defer is set.
bitval := s.constInt8(types.Types[TUINT8], 1<<uint(i))
andval := s.newValue2(ssa.OpAnd8, types.Types[TUINT8], deferBits, bitval)
eqVal := s.newValue2(ssa.OpEq8, types.Types[TBOOL], andval, zeroval)
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(eqVal)
b.AddEdgeTo(bEnd)
b.AddEdgeTo(bCond)
bCond.AddEdgeTo(bEnd)
s.startBlock(bCond)
// Clear this bit in deferBits and force store back to stack, so
// we will not try to re-run this defer call if this defer call panics.
nbitval := s.newValue1(ssa.OpCom8, types.Types[TUINT8], bitval)
maskedval := s.newValue2(ssa.OpAnd8, types.Types[TUINT8], deferBits, nbitval)
s.store(types.Types[TUINT8], s.deferBitsAddr, maskedval)
// Use this value for following tests, so we keep previous
// bits cleared.
s.vars[&deferBitsVar] = maskedval
// Generate code to call the function call of the defer, using the
// closure/receiver/args that were stored in argtmps at the point
// of the defer statement.
argStart := Ctxt.FixedFrameSize()
fn := r.n.Left
stksize := fn.Type.ArgWidth()
if r.rcvr != nil {
// rcvr in case of OCALLINTER
v := s.load(r.rcvr.Type.Elem(), r.rcvr)
addr := s.constOffPtrSP(s.f.Config.Types.UintptrPtr, argStart)
s.store(types.Types[TUINTPTR], addr, v)
}
for j, argAddrVal := range r.argVals {
f := getParam(r.n, j)
pt := types.NewPtr(f.Type)
addr := s.constOffPtrSP(pt, argStart+f.Offset)
if !canSSAType(f.Type) {
s.move(f.Type, addr, argAddrVal)
} else {
argVal := s.load(f.Type, argAddrVal)
s.storeType(f.Type, addr, argVal, 0, false)
}
}
var call *ssa.Value
if r.closure != nil {
v := s.load(r.closure.Type.Elem(), r.closure)
s.maybeNilCheckClosure(v, callDefer)
codeptr := s.rawLoad(types.Types[TUINTPTR], v)
call = s.newValue3(ssa.OpClosureCall, types.TypeMem, codeptr, v, s.mem())
} else {
// Do a static call if the original call was a static function or method
call = s.newValue1A(ssa.OpStaticCall, types.TypeMem, fn.Sym.Linksym(), s.mem())
}
call.AuxInt = stksize
s.vars[&memVar] = call
// Make sure that the stack slots with pointers are kept live
// through the call (which is a pre-emption point). Also, we will
// use the first call of the last defer exit to compute liveness
// for the deferreturn, so we want all stack slots to be live.
if r.closureNode != nil {
s.vars[&memVar] = s.newValue1Apos(ssa.OpVarLive, types.TypeMem, r.closureNode, s.mem(), false)
}
if r.rcvrNode != nil {
if types.Haspointers(r.rcvrNode.Type) {
s.vars[&memVar] = s.newValue1Apos(ssa.OpVarLive, types.TypeMem, r.rcvrNode, s.mem(), false)
}
}
for _, argNode := range r.argNodes {
if types.Haspointers(argNode.Type) {
s.vars[&memVar] = s.newValue1Apos(ssa.OpVarLive, types.TypeMem, argNode, s.mem(), false)
}
}
if i == len(s.openDefers)-1 {
// Record the call of the first defer. This will be used
// to set liveness info for the deferreturn (which is also
// used for any location that causes a runtime panic)
s.f.LastDeferExit = call
}
s.endBlock()
s.startBlock(bEnd)
}
}
// Calls the function n using the specified call type.
// Returns the address of the return value (or nil if none).
func (s *state) call(n *Node, k callKind) *ssa.Value {
var sym *types.Sym // target symbol (if static)
var closure *ssa.Value // ptr to closure to run (if dynamic)
var codeptr *ssa.Value // ptr to target code (if dynamic)
var rcvr *ssa.Value // receiver to set
fn := n.Left
switch n.Op {
case OCALLFUNC:
if k == callNormal && fn.Op == ONAME && fn.Class() == PFUNC {
sym = fn.Sym
break
}
closure = s.expr(fn)
if k != callDefer && k != callDeferStack {
// Deferred nil function needs to panic when the function is invoked,
// not the point of defer statement.
s.maybeNilCheckClosure(closure, k)
}
case OCALLMETH:
if fn.Op != ODOTMETH {
s.Fatalf("OCALLMETH: n.Left not an ODOTMETH: %v", fn)
}
if k == callNormal {
sym = fn.Sym
break
}
closure = s.getMethodClosure(fn)
// Note: receiver is already present in n.Rlist, so we don't
// want to set it here.
case OCALLINTER:
if fn.Op != ODOTINTER {
s.Fatalf("OCALLINTER: n.Left not an ODOTINTER: %v", fn.Op)
}
var iclosure *ssa.Value
iclosure, rcvr = s.getClosureAndRcvr(fn)
if k == callNormal {
codeptr = s.load(types.Types[TUINTPTR], iclosure)
} else {
closure = iclosure
}
}
dowidth(fn.Type)
stksize := fn.Type.ArgWidth() // includes receiver, args, and results
// Run all assignments of temps.
// The temps are introduced to avoid overwriting argument
// slots when arguments themselves require function calls.
s.stmtList(n.List)
var call *ssa.Value
if k == callDeferStack {
// Make a defer struct d on the stack.
t := deferstruct(stksize)
d := tempAt(n.Pos, s.curfn, t)
s.vars[&memVar] = s.newValue1A(ssa.OpVarDef, types.TypeMem, d, s.mem())
addr := s.addr(d)
// Must match reflect.go:deferstruct and src/runtime/runtime2.go:_defer.
// 0: siz
s.store(types.Types[TUINT32],
s.newValue1I(ssa.OpOffPtr, types.Types[TUINT32].PtrTo(), t.FieldOff(0), addr),
s.constInt32(types.Types[TUINT32], int32(stksize)))
// 1: started, set in deferprocStack
// 2: heap, set in deferprocStack
// 3: openDefer
// 4: sp, set in deferprocStack
// 5: pc, set in deferprocStack
// 6: fn
s.store(closure.Type,
s.newValue1I(ssa.OpOffPtr, closure.Type.PtrTo(), t.FieldOff(6), addr),
closure)
// 7: panic, set in deferprocStack
// 8: link, set in deferprocStack
// 9: framepc
// 10: varp
// 11: fd
// Then, store all the arguments of the defer call.
ft := fn.Type
off := t.FieldOff(12)
args := n.Rlist.Slice()
// Set receiver (for interface calls). Always a pointer.
if rcvr != nil {
p := s.newValue1I(ssa.OpOffPtr, ft.Recv().Type.PtrTo(), off, addr)
s.store(types.Types[TUINTPTR], p, rcvr)
}
// Set receiver (for method calls).
if n.Op == OCALLMETH {
f := ft.Recv()
s.storeArgWithBase(args[0], f.Type, addr, off+f.Offset)
args = args[1:]
}
// Set other args.
for _, f := range ft.Params().Fields().Slice() {
s.storeArgWithBase(args[0], f.Type, addr, off+f.Offset)
args = args[1:]
}
// Call runtime.deferprocStack with pointer to _defer record.
arg0 := s.constOffPtrSP(types.Types[TUINTPTR], Ctxt.FixedFrameSize())
s.store(types.Types[TUINTPTR], arg0, addr)
call = s.newValue1A(ssa.OpStaticCall, types.TypeMem, deferprocStack, s.mem())
if stksize < int64(Widthptr) {
// We need room for both the call to deferprocStack and the call to
// the deferred function.
stksize = int64(Widthptr)
}
call.AuxInt = stksize
} else {
// Store arguments to stack, including defer/go arguments and receiver for method calls.
// These are written in SP-offset order.
argStart := Ctxt.FixedFrameSize()
// Defer/go args.
if k != callNormal {
// Write argsize and closure (args to newproc/deferproc).
argsize := s.constInt32(types.Types[TUINT32], int32(stksize))
addr := s.constOffPtrSP(s.f.Config.Types.UInt32Ptr, argStart)
s.store(types.Types[TUINT32], addr, argsize)
addr = s.constOffPtrSP(s.f.Config.Types.UintptrPtr, argStart+int64(Widthptr))
s.store(types.Types[TUINTPTR], addr, closure)
stksize += 2 * int64(Widthptr)
argStart += 2 * int64(Widthptr)
}
// Set receiver (for interface calls).
if rcvr != nil {
addr := s.constOffPtrSP(s.f.Config.Types.UintptrPtr, argStart)
s.store(types.Types[TUINTPTR], addr, rcvr)
}
// Write args.
t := n.Left.Type
args := n.Rlist.Slice()
if n.Op == OCALLMETH {
f := t.Recv()
s.storeArg(args[0], f.Type, argStart+f.Offset)
args = args[1:]
}
for i, n := range args {
f := t.Params().Field(i)
s.storeArg(n, f.Type, argStart+f.Offset)
}
// call target
switch {
case k == callDefer:
call = s.newValue1A(ssa.OpStaticCall, types.TypeMem, deferproc, s.mem())
case k == callGo:
call = s.newValue1A(ssa.OpStaticCall, types.TypeMem, newproc, s.mem())
case closure != nil:
// rawLoad because loading the code pointer from a
// closure is always safe, but IsSanitizerSafeAddr
// can't always figure that out currently, and it's
// critical that we not clobber any arguments already
// stored onto the stack.
codeptr = s.rawLoad(types.Types[TUINTPTR], closure)
call = s.newValue3(ssa.OpClosureCall, types.TypeMem, codeptr, closure, s.mem())
case codeptr != nil:
call = s.newValue2(ssa.OpInterCall, types.TypeMem, codeptr, s.mem())
case sym != nil:
call = s.newValue1A(ssa.OpStaticCall, types.TypeMem, sym.Linksym(), s.mem())
default:
s.Fatalf("bad call type %v %v", n.Op, n)
}
call.AuxInt = stksize // Call operations carry the argsize of the callee along with them
}
s.vars[&memVar] = call
// Finish block for defers
if k == callDefer || k == callDeferStack {
b := s.endBlock()
b.Kind = ssa.BlockDefer
b.SetControl(call)
bNext := s.f.NewBlock(ssa.BlockPlain)
b.AddEdgeTo(bNext)
// Add recover edge to exit code.
r := s.f.NewBlock(ssa.BlockPlain)
s.startBlock(r)
s.exit()
b.AddEdgeTo(r)
b.Likely = ssa.BranchLikely
s.startBlock(bNext)
}
res := n.Left.Type.Results()
if res.NumFields() == 0 || k != callNormal {
// call has no return value. Continue with the next statement.
return nil
}
fp := res.Field(0)
return s.constOffPtrSP(types.NewPtr(fp.Type), fp.Offset+Ctxt.FixedFrameSize())
}
// maybeNilCheckClosure checks if a nil check of a closure is needed in some
// architecture-dependent situations and, if so, emits the nil check.
func (s *state) maybeNilCheckClosure(closure *ssa.Value, k callKind) {
if thearch.LinkArch.Family == sys.Wasm || objabi.GOOS == "aix" && k != callGo {
// On AIX, the closure needs to be verified as fn can be nil, except if it's a call go. This needs to be handled by the runtime to have the "go of nil func value" error.
// TODO(neelance): On other architectures this should be eliminated by the optimization steps
s.nilCheck(closure)
}
}
// getMethodClosure returns a value representing the closure for a method call
func (s *state) getMethodClosure(fn *Node) *ssa.Value {
// Make a name n2 for the function.
// fn.Sym might be sync.(*Mutex).Unlock.
// Make a PFUNC node out of that, then evaluate it.
// We get back an SSA value representing &sync.(*Mutex).Unlock·f.
// We can then pass that to defer or go.
n2 := newnamel(fn.Pos, fn.Sym)
n2.Name.Curfn = s.curfn
n2.SetClass(PFUNC)
// n2.Sym already existed, so it's already marked as a function.
n2.Pos = fn.Pos
n2.Type = types.Types[TUINT8] // dummy type for a static closure. Could use runtime.funcval if we had it.
return s.expr(n2)
}
// getClosureAndRcvr returns values for the appropriate closure and receiver of an
// interface call
func (s *state) getClosureAndRcvr(fn *Node) (*ssa.Value, *ssa.Value) {
i := s.expr(fn.Left)
itab := s.newValue1(ssa.OpITab, types.Types[TUINTPTR], i)
s.nilCheck(itab)
itabidx := fn.Xoffset + 2*int64(Widthptr) + 8 // offset of fun field in runtime.itab
closure := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.UintptrPtr, itabidx, itab)
rcvr := s.newValue1(ssa.OpIData, types.Types[TUINTPTR], i)
return closure, rcvr
}
// etypesign returns the signed-ness of e, for integer/pointer etypes.
// -1 means signed, +1 means unsigned, 0 means non-integer/non-pointer.
func etypesign(e types.EType) int8 {
switch e {
case TINT8, TINT16, TINT32, TINT64, TINT:
return -1
case TUINT8, TUINT16, TUINT32, TUINT64, TUINT, TUINTPTR, TUNSAFEPTR:
return +1
}
return 0
}
// addr converts the address of the expression n to SSA, adds it to s and returns the SSA result.
// The value that the returned Value represents is guaranteed to be non-nil.
func (s *state) addr(n *Node) *ssa.Value {
if n.Op != ONAME {
s.pushLine(n.Pos)
defer s.popLine()
}
t := types.NewPtr(n.Type)
switch n.Op {
case ONAME:
switch n.Class() {
case PEXTERN:
// global variable
v := s.entryNewValue1A(ssa.OpAddr, t, n.Sym.Linksym(), s.sb)
// TODO: Make OpAddr use AuxInt as well as Aux.
if n.Xoffset != 0 {
v = s.entryNewValue1I(ssa.OpOffPtr, v.Type, n.Xoffset, v)
}
return v
case PPARAM:
// parameter slot
v := s.decladdrs[n]
if v != nil {
return v
}
if n == nodfp {
// Special arg that points to the frame pointer (Used by ORECOVER).
return s.entryNewValue2A(ssa.OpLocalAddr, t, n, s.sp, s.startmem)
}
s.Fatalf("addr of undeclared ONAME %v. declared: %v", n, s.decladdrs)
return nil
case PAUTO:
return s.newValue2Apos(ssa.OpLocalAddr, t, n, s.sp, s.mem(), !n.IsAutoTmp())
case PPARAMOUT: // Same as PAUTO -- cannot generate LEA early.
// ensure that we reuse symbols for out parameters so
// that cse works on their addresses
return s.newValue2Apos(ssa.OpLocalAddr, t, n, s.sp, s.mem(), true)
default:
s.Fatalf("variable address class %v not implemented", n.Class())
return nil
}
case ORESULT:
// load return from callee
return s.constOffPtrSP(t, n.Xoffset)
case OINDEX:
if n.Left.Type.IsSlice() {
a := s.expr(n.Left)
i := s.expr(n.Right)
len := s.newValue1(ssa.OpSliceLen, types.Types[TINT], a)
i = s.boundsCheck(i, len, ssa.BoundsIndex, n.Bounded())
p := s.newValue1(ssa.OpSlicePtr, t, a)
return s.newValue2(ssa.OpPtrIndex, t, p, i)
} else { // array
a := s.addr(n.Left)
i := s.expr(n.Right)
len := s.constInt(types.Types[TINT], n.Left.Type.NumElem())
i = s.boundsCheck(i, len, ssa.BoundsIndex, n.Bounded())
return s.newValue2(ssa.OpPtrIndex, types.NewPtr(n.Left.Type.Elem()), a, i)
}
case ODEREF:
return s.exprPtr(n.Left, n.Bounded(), n.Pos)
case ODOT:
p := s.addr(n.Left)
return s.newValue1I(ssa.OpOffPtr, t, n.Xoffset, p)
case ODOTPTR:
p := s.exprPtr(n.Left, n.Bounded(), n.Pos)
return s.newValue1I(ssa.OpOffPtr, t, n.Xoffset, p)
case OCLOSUREVAR:
return s.newValue1I(ssa.OpOffPtr, t, n.Xoffset,
s.entryNewValue0(ssa.OpGetClosurePtr, s.f.Config.Types.BytePtr))
case OCONVNOP:
addr := s.addr(n.Left)
return s.newValue1(ssa.OpCopy, t, addr) // ensure that addr has the right type
case OCALLFUNC, OCALLINTER, OCALLMETH:
return s.call(n, callNormal)
case ODOTTYPE:
v, _ := s.dottype(n, false)
if v.Op != ssa.OpLoad {
s.Fatalf("dottype of non-load")
}
if v.Args[1] != s.mem() {
s.Fatalf("memory no longer live from dottype load")
}
return v.Args[0]
default:
s.Fatalf("unhandled addr %v", n.Op)
return nil
}
}
// canSSA reports whether n is SSA-able.
// n must be an ONAME (or an ODOT sequence with an ONAME base).
func (s *state) canSSA(n *Node) bool {
if Debug['N'] != 0 {
return false
}
for n.Op == ODOT || (n.Op == OINDEX && n.Left.Type.IsArray()) {
n = n.Left
}
if n.Op != ONAME {
return false
}
if n.Name.Addrtaken() {
return false
}
if n.isParamHeapCopy() {
return false
}
if n.Class() == PAUTOHEAP {
s.Fatalf("canSSA of PAUTOHEAP %v", n)
}
switch n.Class() {
case PEXTERN:
return false
case PPARAMOUT:
if s.hasdefer {
// TODO: handle this case? Named return values must be
// in memory so that the deferred function can see them.
// Maybe do: if !strings.HasPrefix(n.String(), "~") { return false }
// Or maybe not, see issue 18860. Even unnamed return values
// must be written back so if a defer recovers, the caller can see them.
return false
}
if s.cgoUnsafeArgs {
// Cgo effectively takes the address of all result args,
// but the compiler can't see that.
return false
}
}
if n.Class() == PPARAM && n.Sym != nil && n.Sym.Name == ".this" {
// wrappers generated by genwrapper need to update
// the .this pointer in place.
// TODO: treat as a PPARMOUT?
return false
}
return canSSAType(n.Type)
// TODO: try to make more variables SSAable?
}
// canSSA reports whether variables of type t are SSA-able.
func canSSAType(t *types.Type) bool {
dowidth(t)
if t.Width > int64(4*Widthptr) {
// 4*Widthptr is an arbitrary constant. We want it
// to be at least 3*Widthptr so slices can be registerized.
// Too big and we'll introduce too much register pressure.
return false
}
switch t.Etype {
case TARRAY:
// We can't do larger arrays because dynamic indexing is
// not supported on SSA variables.
// TODO: allow if all indexes are constant.
if t.NumElem() <= 1 {
return canSSAType(t.Elem())
}
return false
case TSTRUCT:
if t.NumFields() > ssa.MaxStruct {
return false
}
for _, t1 := range t.Fields().Slice() {
if !canSSAType(t1.Type) {
return false
}
}
return true
default:
return true
}
}
// exprPtr evaluates n to a pointer and nil-checks it.
func (s *state) exprPtr(n *Node, bounded bool, lineno src.XPos) *ssa.Value {
p := s.expr(n)
if bounded || n.NonNil() {
if s.f.Frontend().Debug_checknil() && lineno.Line() > 1 {
s.f.Warnl(lineno, "removed nil check")
}
return p
}
s.nilCheck(p)
return p
}
// nilCheck generates nil pointer checking code.
// Used only for automatically inserted nil checks,
// not for user code like 'x != nil'.
func (s *state) nilCheck(ptr *ssa.Value) {
if disable_checknil != 0 || s.curfn.Func.NilCheckDisabled() {
return
}
s.newValue2(ssa.OpNilCheck, types.TypeVoid, ptr, s.mem())
}
// boundsCheck generates bounds checking code. Checks if 0 <= idx <[=] len, branches to exit if not.
// Starts a new block on return.
// On input, len must be converted to full int width and be nonnegative.
// Returns idx converted to full int width.
// If bounded is true then caller guarantees the index is not out of bounds
// (but boundsCheck will still extend the index to full int width).
func (s *state) boundsCheck(idx, len *ssa.Value, kind ssa.BoundsKind, bounded bool) *ssa.Value {
idx = s.extendIndex(idx, len, kind, bounded)
if bounded || Debug['B'] != 0 {
// If bounded or bounds checking is flag-disabled, then no check necessary,
// just return the extended index.
//
// Here, bounded == true if the compiler generated the index itself,
// such as in the expansion of a slice initializer. These indexes are
// compiler-generated, not Go program variables, so they cannot be
// attacker-controlled, so we can omit Spectre masking as well.
//
// Note that we do not want to omit Spectre masking in code like:
//
// if 0 <= i && i < len(x) {
// use(x[i])
// }
//
// Lucky for us, bounded==false for that code.
// In that case (handled below), we emit a bound check (and Spectre mask)
// and then the prove pass will remove the bounds check.
// In theory the prove pass could potentially remove certain
// Spectre masks, but it's very delicate and probably better
// to be conservative and leave them all in.
return idx
}
bNext := s.f.NewBlock(ssa.BlockPlain)
bPanic := s.f.NewBlock(ssa.BlockExit)
if !idx.Type.IsSigned() {
switch kind {
case ssa.BoundsIndex:
kind = ssa.BoundsIndexU
case ssa.BoundsSliceAlen:
kind = ssa.BoundsSliceAlenU
case ssa.BoundsSliceAcap:
kind = ssa.BoundsSliceAcapU
case ssa.BoundsSliceB:
kind = ssa.BoundsSliceBU
case ssa.BoundsSlice3Alen:
kind = ssa.BoundsSlice3AlenU
case ssa.BoundsSlice3Acap:
kind = ssa.BoundsSlice3AcapU
case ssa.BoundsSlice3B:
kind = ssa.BoundsSlice3BU
case ssa.BoundsSlice3C:
kind = ssa.BoundsSlice3CU
}
}
var cmp *ssa.Value
if kind == ssa.BoundsIndex || kind == ssa.BoundsIndexU {
cmp = s.newValue2(ssa.OpIsInBounds, types.Types[TBOOL], idx, len)
} else {
cmp = s.newValue2(ssa.OpIsSliceInBounds, types.Types[TBOOL], idx, len)
}
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(cmp)
b.Likely = ssa.BranchLikely
b.AddEdgeTo(bNext)
b.AddEdgeTo(bPanic)
s.startBlock(bPanic)
if thearch.LinkArch.Family == sys.Wasm {
// TODO(khr): figure out how to do "register" based calling convention for bounds checks.
// Should be similar to gcWriteBarrier, but I can't make it work.
s.rtcall(BoundsCheckFunc[kind], false, nil, idx, len)
} else {
mem := s.newValue3I(ssa.OpPanicBounds, types.TypeMem, int64(kind), idx, len, s.mem())
s.endBlock().SetControl(mem)
}
s.startBlock(bNext)
// In Spectre index mode, apply an appropriate mask to avoid speculative out-of-bounds accesses.
if spectreIndex {
op := ssa.OpSpectreIndex
if kind != ssa.BoundsIndex && kind != ssa.BoundsIndexU {
op = ssa.OpSpectreSliceIndex
}
idx = s.newValue2(op, types.Types[TINT], idx, len)
}
return idx
}
// If cmp (a bool) is false, panic using the given function.
func (s *state) check(cmp *ssa.Value, fn *obj.LSym) {
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(cmp)
b.Likely = ssa.BranchLikely
bNext := s.f.NewBlock(ssa.BlockPlain)
line := s.peekPos()
pos := Ctxt.PosTable.Pos(line)
fl := funcLine{f: fn, base: pos.Base(), line: pos.Line()}
bPanic := s.panics[fl]
if bPanic == nil {
bPanic = s.f.NewBlock(ssa.BlockPlain)
s.panics[fl] = bPanic
s.startBlock(bPanic)
// The panic call takes/returns memory to ensure that the right
// memory state is observed if the panic happens.
s.rtcall(fn, false, nil)
}
b.AddEdgeTo(bNext)
b.AddEdgeTo(bPanic)
s.startBlock(bNext)
}
func (s *state) intDivide(n *Node, a, b *ssa.Value) *ssa.Value {
needcheck := true
switch b.Op {
case ssa.OpConst8, ssa.OpConst16, ssa.OpConst32, ssa.OpConst64:
if b.AuxInt != 0 {
needcheck = false
}
}
if needcheck {
// do a size-appropriate check for zero
cmp := s.newValue2(s.ssaOp(ONE, n.Type), types.Types[TBOOL], b, s.zeroVal(n.Type))
s.check(cmp, panicdivide)
}
return s.newValue2(s.ssaOp(n.Op, n.Type), a.Type, a, b)
}
// rtcall issues a call to the given runtime function fn with the listed args.
// Returns a slice of results of the given result types.
// The call is added to the end of the current block.
// If returns is false, the block is marked as an exit block.
func (s *state) rtcall(fn *obj.LSym, returns bool, results []*types.Type, args ...*ssa.Value) []*ssa.Value {
// Write args to the stack
off := Ctxt.FixedFrameSize()
for _, arg := range args {
t := arg.Type
off = Rnd(off, t.Alignment())
ptr := s.constOffPtrSP(t.PtrTo(), off)
size := t.Size()
s.store(t, ptr, arg)
off += size
}
off = Rnd(off, int64(Widthreg))
// Issue call
call := s.newValue1A(ssa.OpStaticCall, types.TypeMem, fn, s.mem())
s.vars[&memVar] = call
if !returns {
// Finish block
b := s.endBlock()
b.Kind = ssa.BlockExit
b.SetControl(call)
call.AuxInt = off - Ctxt.FixedFrameSize()
if len(results) > 0 {
s.Fatalf("panic call can't have results")
}
return nil
}
// Load results
res := make([]*ssa.Value, len(results))
for i, t := range results {
off = Rnd(off, t.Alignment())
ptr := s.constOffPtrSP(types.NewPtr(t), off)
res[i] = s.load(t, ptr)
off += t.Size()
}
off = Rnd(off, int64(Widthptr))
// Remember how much callee stack space we needed.
call.AuxInt = off
return res
}
// do *left = right for type t.
func (s *state) storeType(t *types.Type, left, right *ssa.Value, skip skipMask, leftIsStmt bool) {
s.instrument(t, left, true)
if skip == 0 && (!types.Haspointers(t) || ssa.IsStackAddr(left)) {
// Known to not have write barrier. Store the whole type.
s.vars[&memVar] = s.newValue3Apos(ssa.OpStore, types.TypeMem, t, left, right, s.mem(), leftIsStmt)
return
}
// store scalar fields first, so write barrier stores for
// pointer fields can be grouped together, and scalar values
// don't need to be live across the write barrier call.
// TODO: if the writebarrier pass knows how to reorder stores,
// we can do a single store here as long as skip==0.
s.storeTypeScalars(t, left, right, skip)
if skip&skipPtr == 0 && types.Haspointers(t) {
s.storeTypePtrs(t, left, right)
}
}
// do *left = right for all scalar (non-pointer) parts of t.
func (s *state) storeTypeScalars(t *types.Type, left, right *ssa.Value, skip skipMask) {
switch {
case t.IsBoolean() || t.IsInteger() || t.IsFloat() || t.IsComplex():
s.store(t, left, right)
case t.IsPtrShaped():
// no scalar fields.
case t.IsString():
if skip&skipLen != 0 {
return
}
len := s.newValue1(ssa.OpStringLen, types.Types[TINT], right)
lenAddr := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.IntPtr, s.config.PtrSize, left)
s.store(types.Types[TINT], lenAddr, len)
case t.IsSlice():
if skip&skipLen == 0 {
len := s.newValue1(ssa.OpSliceLen, types.Types[TINT], right)
lenAddr := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.IntPtr, s.config.PtrSize, left)
s.store(types.Types[TINT], lenAddr, len)
}
if skip&skipCap == 0 {
cap := s.newValue1(ssa.OpSliceCap, types.Types[TINT], right)
capAddr := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.IntPtr, 2*s.config.PtrSize, left)
s.store(types.Types[TINT], capAddr, cap)
}
case t.IsInterface():
// itab field doesn't need a write barrier (even though it is a pointer).
itab := s.newValue1(ssa.OpITab, s.f.Config.Types.BytePtr, right)
s.store(types.Types[TUINTPTR], left, itab)
case t.IsStruct():
n := t.NumFields()
for i := 0; i < n; i++ {
ft := t.FieldType(i)
addr := s.newValue1I(ssa.OpOffPtr, ft.PtrTo(), t.FieldOff(i), left)
val := s.newValue1I(ssa.OpStructSelect, ft, int64(i), right)
s.storeTypeScalars(ft, addr, val, 0)
}
case t.IsArray() && t.NumElem() == 0:
// nothing
case t.IsArray() && t.NumElem() == 1:
s.storeTypeScalars(t.Elem(), left, s.newValue1I(ssa.OpArraySelect, t.Elem(), 0, right), 0)
default:
s.Fatalf("bad write barrier type %v", t)
}
}
// do *left = right for all pointer parts of t.
func (s *state) storeTypePtrs(t *types.Type, left, right *ssa.Value) {
switch {
case t.IsPtrShaped():
s.store(t, left, right)
case t.IsString():
ptr := s.newValue1(ssa.OpStringPtr, s.f.Config.Types.BytePtr, right)
s.store(s.f.Config.Types.BytePtr, left, ptr)
case t.IsSlice():
elType := types.NewPtr(t.Elem())
ptr := s.newValue1(ssa.OpSlicePtr, elType, right)
s.store(elType, left, ptr)
case t.IsInterface():
// itab field is treated as a scalar.
idata := s.newValue1(ssa.OpIData, s.f.Config.Types.BytePtr, right)
idataAddr := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.BytePtrPtr, s.config.PtrSize, left)
s.store(s.f.Config.Types.BytePtr, idataAddr, idata)
case t.IsStruct():
n := t.NumFields()
for i := 0; i < n; i++ {
ft := t.FieldType(i)
if !types.Haspointers(ft) {
continue
}
addr := s.newValue1I(ssa.OpOffPtr, ft.PtrTo(), t.FieldOff(i), left)
val := s.newValue1I(ssa.OpStructSelect, ft, int64(i), right)
s.storeTypePtrs(ft, addr, val)
}
case t.IsArray() && t.NumElem() == 0:
// nothing
case t.IsArray() && t.NumElem() == 1:
s.storeTypePtrs(t.Elem(), left, s.newValue1I(ssa.OpArraySelect, t.Elem(), 0, right))
default:
s.Fatalf("bad write barrier type %v", t)
}
}
func (s *state) storeArg(n *Node, t *types.Type, off int64) {
s.storeArgWithBase(n, t, s.sp, off)
}
func (s *state) storeArgWithBase(n *Node, t *types.Type, base *ssa.Value, off int64) {
pt := types.NewPtr(t)
var addr *ssa.Value
if base == s.sp {
// Use special routine that avoids allocation on duplicate offsets.
addr = s.constOffPtrSP(pt, off)
} else {
addr = s.newValue1I(ssa.OpOffPtr, pt, off, base)
}
if !canSSAType(t) {
a := s.addr(n)
s.move(t, addr, a)
return
}
a := s.expr(n)
s.storeType(t, addr, a, 0, false)
}
// slice computes the slice v[i:j:k] and returns ptr, len, and cap of result.
// i,j,k may be nil, in which case they are set to their default value.
// v may be a slice, string or pointer to an array.
func (s *state) slice(v, i, j, k *ssa.Value, bounded bool) (p, l, c *ssa.Value) {
t := v.Type
var ptr, len, cap *ssa.Value
switch {
case t.IsSlice():
ptr = s.newValue1(ssa.OpSlicePtr, types.NewPtr(t.Elem()), v)
len = s.newValue1(ssa.OpSliceLen, types.Types[TINT], v)
cap = s.newValue1(ssa.OpSliceCap, types.Types[TINT], v)
case t.IsString():
ptr = s.newValue1(ssa.OpStringPtr, types.NewPtr(types.Types[TUINT8]), v)
len = s.newValue1(ssa.OpStringLen, types.Types[TINT], v)
cap = len
case t.IsPtr():
if !t.Elem().IsArray() {
s.Fatalf("bad ptr to array in slice %v\n", t)
}
s.nilCheck(v)
ptr = s.newValue1(ssa.OpCopy, types.NewPtr(t.Elem().Elem()), v)
len = s.constInt(types.Types[TINT], t.Elem().NumElem())
cap = len
default:
s.Fatalf("bad type in slice %v\n", t)
}
// Set default values
if i == nil {
i = s.constInt(types.Types[TINT], 0)
}
if j == nil {
j = len
}
three := true
if k == nil {
three = false
k = cap
}
// Panic if slice indices are not in bounds.
// Make sure we check these in reverse order so that we're always
// comparing against a value known to be nonnegative. See issue 28797.
if three {
if k != cap {
kind := ssa.BoundsSlice3Alen
if t.IsSlice() {
kind = ssa.BoundsSlice3Acap
}
k = s.boundsCheck(k, cap, kind, bounded)
}
if j != k {
j = s.boundsCheck(j, k, ssa.BoundsSlice3B, bounded)
}
i = s.boundsCheck(i, j, ssa.BoundsSlice3C, bounded)
} else {
if j != k {
kind := ssa.BoundsSliceAlen
if t.IsSlice() {
kind = ssa.BoundsSliceAcap
}
j = s.boundsCheck(j, k, kind, bounded)
}
i = s.boundsCheck(i, j, ssa.BoundsSliceB, bounded)
}
// Word-sized integer operations.
subOp := s.ssaOp(OSUB, types.Types[TINT])
mulOp := s.ssaOp(OMUL, types.Types[TINT])
andOp := s.ssaOp(OAND, types.Types[TINT])
// Calculate the length (rlen) and capacity (rcap) of the new slice.
// For strings the capacity of the result is unimportant. However,
// we use rcap to test if we've generated a zero-length slice.
// Use length of strings for that.
rlen := s.newValue2(subOp, types.Types[TINT], j, i)
rcap := rlen
if j != k && !t.IsString() {
rcap = s.newValue2(subOp, types.Types[TINT], k, i)
}
if (i.Op == ssa.OpConst64 || i.Op == ssa.OpConst32) && i.AuxInt == 0 {
// No pointer arithmetic necessary.
return ptr, rlen, rcap
}
// Calculate the base pointer (rptr) for the new slice.
//
// Generate the following code assuming that indexes are in bounds.
// The masking is to make sure that we don't generate a slice
// that points to the next object in memory. We cannot just set
// the pointer to nil because then we would create a nil slice or
// string.
//
// rcap = k - i
// rlen = j - i
// rptr = ptr + (mask(rcap) & (i * stride))
//
// Where mask(x) is 0 if x==0 and -1 if x>0 and stride is the width
// of the element type.
stride := s.constInt(types.Types[TINT], ptr.Type.Elem().Width)
// The delta is the number of bytes to offset ptr by.
delta := s.newValue2(mulOp, types.Types[TINT], i, stride)
// If we're slicing to the point where the capacity is zero,
// zero out the delta.
mask := s.newValue1(ssa.OpSlicemask, types.Types[TINT], rcap)
delta = s.newValue2(andOp, types.Types[TINT], delta, mask)
// Compute rptr = ptr + delta.
rptr := s.newValue2(ssa.OpAddPtr, ptr.Type, ptr, delta)
return rptr, rlen, rcap
}
type u642fcvtTab struct {
leq, cvt2F, and, rsh, or, add ssa.Op
one func(*state, *types.Type, int64) *ssa.Value
}
var u64_f64 = u642fcvtTab{
leq: ssa.OpLeq64,
cvt2F: ssa.OpCvt64to64F,
and: ssa.OpAnd64,
rsh: ssa.OpRsh64Ux64,
or: ssa.OpOr64,
add: ssa.OpAdd64F,
one: (*state).constInt64,
}
var u64_f32 = u642fcvtTab{
leq: ssa.OpLeq64,
cvt2F: ssa.OpCvt64to32F,
and: ssa.OpAnd64,
rsh: ssa.OpRsh64Ux64,
or: ssa.OpOr64,
add: ssa.OpAdd32F,
one: (*state).constInt64,
}
func (s *state) uint64Tofloat64(n *Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value {
return s.uint64Tofloat(&u64_f64, n, x, ft, tt)
}
func (s *state) uint64Tofloat32(n *Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value {
return s.uint64Tofloat(&u64_f32, n, x, ft, tt)
}
func (s *state) uint64Tofloat(cvttab *u642fcvtTab, n *Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value {
// if x >= 0 {
// result = (floatY) x
// } else {
// y = uintX(x) ; y = x & 1
// z = uintX(x) ; z = z >> 1
// z = z >> 1
// z = z | y
// result = floatY(z)
// result = result + result
// }
//
// Code borrowed from old code generator.
// What's going on: large 64-bit "unsigned" looks like
// negative number to hardware's integer-to-float
// conversion. However, because the mantissa is only
// 63 bits, we don't need the LSB, so instead we do an
// unsigned right shift (divide by two), convert, and
// double. However, before we do that, we need to be
// sure that we do not lose a "1" if that made the
// difference in the resulting rounding. Therefore, we
// preserve it, and OR (not ADD) it back in. The case
// that matters is when the eleven discarded bits are
// equal to 10000000001; that rounds up, and the 1 cannot
// be lost else it would round down if the LSB of the
// candidate mantissa is 0.
cmp := s.newValue2(cvttab.leq, types.Types[TBOOL], s.zeroVal(ft), x)
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(cmp)
b.Likely = ssa.BranchLikely
bThen := s.f.NewBlock(ssa.BlockPlain)
bElse := s.f.NewBlock(ssa.BlockPlain)
bAfter := s.f.NewBlock(ssa.BlockPlain)
b.AddEdgeTo(bThen)
s.startBlock(bThen)
a0 := s.newValue1(cvttab.cvt2F, tt, x)
s.vars[n] = a0
s.endBlock()
bThen.AddEdgeTo(bAfter)
b.AddEdgeTo(bElse)
s.startBlock(bElse)
one := cvttab.one(s, ft, 1)
y := s.newValue2(cvttab.and, ft, x, one)
z := s.newValue2(cvttab.rsh, ft, x, one)
z = s.newValue2(cvttab.or, ft, z, y)
a := s.newValue1(cvttab.cvt2F, tt, z)
a1 := s.newValue2(cvttab.add, tt, a, a)
s.vars[n] = a1
s.endBlock()
bElse.AddEdgeTo(bAfter)
s.startBlock(bAfter)
return s.variable(n, n.Type)
}
type u322fcvtTab struct {
cvtI2F, cvtF2F ssa.Op
}
var u32_f64 = u322fcvtTab{
cvtI2F: ssa.OpCvt32to64F,
cvtF2F: ssa.OpCopy,
}
var u32_f32 = u322fcvtTab{
cvtI2F: ssa.OpCvt32to32F,
cvtF2F: ssa.OpCvt64Fto32F,
}
func (s *state) uint32Tofloat64(n *Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value {
return s.uint32Tofloat(&u32_f64, n, x, ft, tt)
}
func (s *state) uint32Tofloat32(n *Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value {
return s.uint32Tofloat(&u32_f32, n, x, ft, tt)
}
func (s *state) uint32Tofloat(cvttab *u322fcvtTab, n *Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value {
// if x >= 0 {
// result = floatY(x)
// } else {
// result = floatY(float64(x) + (1<<32))
// }
cmp := s.newValue2(ssa.OpLeq32, types.Types[TBOOL], s.zeroVal(ft), x)
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(cmp)
b.Likely = ssa.BranchLikely
bThen := s.f.NewBlock(ssa.BlockPlain)
bElse := s.f.NewBlock(ssa.BlockPlain)
bAfter := s.f.NewBlock(ssa.BlockPlain)
b.AddEdgeTo(bThen)
s.startBlock(bThen)
a0 := s.newValue1(cvttab.cvtI2F, tt, x)
s.vars[n] = a0
s.endBlock()
bThen.AddEdgeTo(bAfter)
b.AddEdgeTo(bElse)
s.startBlock(bElse)
a1 := s.newValue1(ssa.OpCvt32to64F, types.Types[TFLOAT64], x)
twoToThe32 := s.constFloat64(types.Types[TFLOAT64], float64(1<<32))
a2 := s.newValue2(ssa.OpAdd64F, types.Types[TFLOAT64], a1, twoToThe32)
a3 := s.newValue1(cvttab.cvtF2F, tt, a2)
s.vars[n] = a3
s.endBlock()
bElse.AddEdgeTo(bAfter)
s.startBlock(bAfter)
return s.variable(n, n.Type)
}
// referenceTypeBuiltin generates code for the len/cap builtins for maps and channels.
func (s *state) referenceTypeBuiltin(n *Node, x *ssa.Value) *ssa.Value {
if !n.Left.Type.IsMap() && !n.Left.Type.IsChan() {
s.Fatalf("node must be a map or a channel")
}
// if n == nil {
// return 0
// } else {
// // len
// return *((*int)n)
// // cap
// return *(((*int)n)+1)
// }
lenType := n.Type
nilValue := s.constNil(types.Types[TUINTPTR])
cmp := s.newValue2(ssa.OpEqPtr, types.Types[TBOOL], x, nilValue)
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(cmp)
b.Likely = ssa.BranchUnlikely
bThen := s.f.NewBlock(ssa.BlockPlain)
bElse := s.f.NewBlock(ssa.BlockPlain)
bAfter := s.f.NewBlock(ssa.BlockPlain)
// length/capacity of a nil map/chan is zero
b.AddEdgeTo(bThen)
s.startBlock(bThen)
s.vars[n] = s.zeroVal(lenType)
s.endBlock()
bThen.AddEdgeTo(bAfter)
b.AddEdgeTo(bElse)
s.startBlock(bElse)
switch n.Op {
case OLEN:
// length is stored in the first word for map/chan
s.vars[n] = s.load(lenType, x)
case OCAP:
// capacity is stored in the second word for chan
sw := s.newValue1I(ssa.OpOffPtr, lenType.PtrTo(), lenType.Width, x)
s.vars[n] = s.load(lenType, sw)
default:
s.Fatalf("op must be OLEN or OCAP")
}
s.endBlock()
bElse.AddEdgeTo(bAfter)
s.startBlock(bAfter)
return s.variable(n, lenType)
}
type f2uCvtTab struct {
ltf, cvt2U, subf, or ssa.Op
floatValue func(*state, *types.Type, float64) *ssa.Value
intValue func(*state, *types.Type, int64) *ssa.Value
cutoff uint64
}
var f32_u64 = f2uCvtTab{
ltf: ssa.OpLess32F,
cvt2U: ssa.OpCvt32Fto64,
subf: ssa.OpSub32F,
or: ssa.OpOr64,
floatValue: (*state).constFloat32,
intValue: (*state).constInt64,
cutoff: 1 << 63,
}
var f64_u64 = f2uCvtTab{
ltf: ssa.OpLess64F,
cvt2U: ssa.OpCvt64Fto64,
subf: ssa.OpSub64F,
or: ssa.OpOr64,
floatValue: (*state).constFloat64,
intValue: (*state).constInt64,
cutoff: 1 << 63,
}
var f32_u32 = f2uCvtTab{
ltf: ssa.OpLess32F,
cvt2U: ssa.OpCvt32Fto32,
subf: ssa.OpSub32F,
or: ssa.OpOr32,
floatValue: (*state).constFloat32,
intValue: func(s *state, t *types.Type, v int64) *ssa.Value { return s.constInt32(t, int32(v)) },
cutoff: 1 << 31,
}
var f64_u32 = f2uCvtTab{
ltf: ssa.OpLess64F,
cvt2U: ssa.OpCvt64Fto32,
subf: ssa.OpSub64F,
or: ssa.OpOr32,
floatValue: (*state).constFloat64,
intValue: func(s *state, t *types.Type, v int64) *ssa.Value { return s.constInt32(t, int32(v)) },
cutoff: 1 << 31,
}
func (s *state) float32ToUint64(n *Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value {
return s.floatToUint(&f32_u64, n, x, ft, tt)
}
func (s *state) float64ToUint64(n *Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value {
return s.floatToUint(&f64_u64, n, x, ft, tt)
}
func (s *state) float32ToUint32(n *Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value {
return s.floatToUint(&f32_u32, n, x, ft, tt)
}
func (s *state) float64ToUint32(n *Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value {
return s.floatToUint(&f64_u32, n, x, ft, tt)
}
func (s *state) floatToUint(cvttab *f2uCvtTab, n *Node, x *ssa.Value, ft, tt *types.Type) *ssa.Value {
// cutoff:=1<<(intY_Size-1)
// if x < floatX(cutoff) {
// result = uintY(x)
// } else {
// y = x - floatX(cutoff)
// z = uintY(y)
// result = z | -(cutoff)
// }
cutoff := cvttab.floatValue(s, ft, float64(cvttab.cutoff))
cmp := s.newValue2(cvttab.ltf, types.Types[TBOOL], x, cutoff)
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(cmp)
b.Likely = ssa.BranchLikely
bThen := s.f.NewBlock(ssa.BlockPlain)
bElse := s.f.NewBlock(ssa.BlockPlain)
bAfter := s.f.NewBlock(ssa.BlockPlain)
b.AddEdgeTo(bThen)
s.startBlock(bThen)
a0 := s.newValue1(cvttab.cvt2U, tt, x)
s.vars[n] = a0
s.endBlock()
bThen.AddEdgeTo(bAfter)
b.AddEdgeTo(bElse)
s.startBlock(bElse)
y := s.newValue2(cvttab.subf, ft, x, cutoff)
y = s.newValue1(cvttab.cvt2U, tt, y)
z := cvttab.intValue(s, tt, int64(-cvttab.cutoff))
a1 := s.newValue2(cvttab.or, tt, y, z)
s.vars[n] = a1
s.endBlock()
bElse.AddEdgeTo(bAfter)
s.startBlock(bAfter)
return s.variable(n, n.Type)
}
// dottype generates SSA for a type assertion node.
// commaok indicates whether to panic or return a bool.
// If commaok is false, resok will be nil.
func (s *state) dottype(n *Node, commaok bool) (res, resok *ssa.Value) {
iface := s.expr(n.Left) // input interface
target := s.expr(n.Right) // target type
byteptr := s.f.Config.Types.BytePtr
if n.Type.IsInterface() {
if n.Type.IsEmptyInterface() {
// Converting to an empty interface.
// Input could be an empty or nonempty interface.
if Debug_typeassert > 0 {
Warnl(n.Pos, "type assertion inlined")
}
// Get itab/type field from input.
itab := s.newValue1(ssa.OpITab, byteptr, iface)
// Conversion succeeds iff that field is not nil.
cond := s.newValue2(ssa.OpNeqPtr, types.Types[TBOOL], itab, s.constNil(byteptr))
if n.Left.Type.IsEmptyInterface() && commaok {
// Converting empty interface to empty interface with ,ok is just a nil check.
return iface, cond
}
// Branch on nilness.
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(cond)
b.Likely = ssa.BranchLikely
bOk := s.f.NewBlock(ssa.BlockPlain)
bFail := s.f.NewBlock(ssa.BlockPlain)
b.AddEdgeTo(bOk)
b.AddEdgeTo(bFail)
if !commaok {
// On failure, panic by calling panicnildottype.
s.startBlock(bFail)
s.rtcall(panicnildottype, false, nil, target)
// On success, return (perhaps modified) input interface.
s.startBlock(bOk)
if n.Left.Type.IsEmptyInterface() {
res = iface // Use input interface unchanged.
return
}
// Load type out of itab, build interface with existing idata.
off := s.newValue1I(ssa.OpOffPtr, byteptr, int64(Widthptr), itab)
typ := s.load(byteptr, off)
idata := s.newValue1(ssa.OpIData, n.Type, iface)
res = s.newValue2(ssa.OpIMake, n.Type, typ, idata)
return
}
s.startBlock(bOk)
// nonempty -> empty
// Need to load type from itab
off := s.newValue1I(ssa.OpOffPtr, byteptr, int64(Widthptr), itab)
s.vars[&typVar] = s.load(byteptr, off)
s.endBlock()
// itab is nil, might as well use that as the nil result.
s.startBlock(bFail)
s.vars[&typVar] = itab
s.endBlock()
// Merge point.
bEnd := s.f.NewBlock(ssa.BlockPlain)
bOk.AddEdgeTo(bEnd)
bFail.AddEdgeTo(bEnd)
s.startBlock(bEnd)
idata := s.newValue1(ssa.OpIData, n.Type, iface)
res = s.newValue2(ssa.OpIMake, n.Type, s.variable(&typVar, byteptr), idata)
resok = cond
delete(s.vars, &typVar)
return
}
// converting to a nonempty interface needs a runtime call.
if Debug_typeassert > 0 {
Warnl(n.Pos, "type assertion not inlined")
}
if n.Left.Type.IsEmptyInterface() {
if commaok {
call := s.rtcall(assertE2I2, true, []*types.Type{n.Type, types.Types[TBOOL]}, target, iface)
return call[0], call[1]
}
return s.rtcall(assertE2I, true, []*types.Type{n.Type}, target, iface)[0], nil
}
if commaok {
call := s.rtcall(assertI2I2, true, []*types.Type{n.Type, types.Types[TBOOL]}, target, iface)
return call[0], call[1]
}
return s.rtcall(assertI2I, true, []*types.Type{n.Type}, target, iface)[0], nil
}
if Debug_typeassert > 0 {
Warnl(n.Pos, "type assertion inlined")
}
// Converting to a concrete type.
direct := isdirectiface(n.Type)
itab := s.newValue1(ssa.OpITab, byteptr, iface) // type word of interface
if Debug_typeassert > 0 {
Warnl(n.Pos, "type assertion inlined")
}
var targetITab *ssa.Value
if n.Left.Type.IsEmptyInterface() {
// Looking for pointer to target type.
targetITab = target
} else {
// Looking for pointer to itab for target type and source interface.
targetITab = s.expr(n.List.First())
}
var tmp *Node // temporary for use with large types
var addr *ssa.Value // address of tmp
if commaok && !canSSAType(n.Type) {
// unSSAable type, use temporary.
// TODO: get rid of some of these temporaries.
tmp = tempAt(n.Pos, s.curfn, n.Type)
s.vars[&memVar] = s.newValue1A(ssa.OpVarDef, types.TypeMem, tmp, s.mem())
addr = s.addr(tmp)
}
cond := s.newValue2(ssa.OpEqPtr, types.Types[TBOOL], itab, targetITab)
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(cond)
b.Likely = ssa.BranchLikely
bOk := s.f.NewBlock(ssa.BlockPlain)
bFail := s.f.NewBlock(ssa.BlockPlain)
b.AddEdgeTo(bOk)
b.AddEdgeTo(bFail)
if !commaok {
// on failure, panic by calling panicdottype
s.startBlock(bFail)
taddr := s.expr(n.Right.Right)
if n.Left.Type.IsEmptyInterface() {
s.rtcall(panicdottypeE, false, nil, itab, target, taddr)
} else {
s.rtcall(panicdottypeI, false, nil, itab, target, taddr)
}
// on success, return data from interface
s.startBlock(bOk)
if direct {
return s.newValue1(ssa.OpIData, n.Type, iface), nil
}
p := s.newValue1(ssa.OpIData, types.NewPtr(n.Type), iface)
return s.load(n.Type, p), nil
}
// commaok is the more complicated case because we have
// a control flow merge point.
bEnd := s.f.NewBlock(ssa.BlockPlain)
// Note that we need a new valVar each time (unlike okVar where we can
// reuse the variable) because it might have a different type every time.
valVar := &Node{Op: ONAME, Sym: &types.Sym{Name: "val"}}
// type assertion succeeded
s.startBlock(bOk)
if tmp == nil {
if direct {
s.vars[valVar] = s.newValue1(ssa.OpIData, n.Type, iface)
} else {
p := s.newValue1(ssa.OpIData, types.NewPtr(n.Type), iface)
s.vars[valVar] = s.load(n.Type, p)
}
} else {
p := s.newValue1(ssa.OpIData, types.NewPtr(n.Type), iface)
s.move(n.Type, addr, p)
}
s.vars[&okVar] = s.constBool(true)
s.endBlock()
bOk.AddEdgeTo(bEnd)
// type assertion failed
s.startBlock(bFail)
if tmp == nil {
s.vars[valVar] = s.zeroVal(n.Type)
} else {
s.zero(n.Type, addr)
}
s.vars[&okVar] = s.constBool(false)
s.endBlock()
bFail.AddEdgeTo(bEnd)
// merge point
s.startBlock(bEnd)
if tmp == nil {
res = s.variable(valVar, n.Type)
delete(s.vars, valVar)
} else {
res = s.load(n.Type, addr)
s.vars[&memVar] = s.newValue1A(ssa.OpVarKill, types.TypeMem, tmp, s.mem())
}
resok = s.variable(&okVar, types.Types[TBOOL])
delete(s.vars, &okVar)
return res, resok
}
// variable returns the value of a variable at the current location.
func (s *state) variable(name *Node, t *types.Type) *ssa.Value {
v := s.vars[name]
if v != nil {
return v
}
v = s.fwdVars[name]
if v != nil {
return v
}
if s.curBlock == s.f.Entry {
// No variable should be live at entry.
s.Fatalf("Value live at entry. It shouldn't be. func %s, node %v, value %v", s.f.Name, name, v)
}
// Make a FwdRef, which records a value that's live on block input.
// We'll find the matching definition as part of insertPhis.
v = s.newValue0A(ssa.OpFwdRef, t, name)
s.fwdVars[name] = v
s.addNamedValue(name, v)
return v
}
func (s *state) mem() *ssa.Value {
return s.variable(&memVar, types.TypeMem)
}
func (s *state) addNamedValue(n *Node, v *ssa.Value) {
if n.Class() == Pxxx {
// Don't track our dummy nodes (&memVar etc.).
return
}
if n.IsAutoTmp() {
// Don't track temporary variables.
return
}
if n.Class() == PPARAMOUT {
// Don't track named output values. This prevents return values
// from being assigned too early. See #14591 and #14762. TODO: allow this.
return
}
if n.Class() == PAUTO && n.Xoffset != 0 {
s.Fatalf("AUTO var with offset %v %d", n, n.Xoffset)
}
loc := ssa.LocalSlot{N: n, Type: n.Type, Off: 0}
values, ok := s.f.NamedValues[loc]
if !ok {
s.f.Names = append(s.f.Names, loc)
}
s.f.NamedValues[loc] = append(values, v)
}
// Generate a disconnected call to a runtime routine and a return.
func gencallret(pp *Progs, sym *obj.LSym) *obj.Prog {
p := pp.Prog(obj.ACALL)
p.To.Type = obj.TYPE_MEM
p.To.Name = obj.NAME_EXTERN
p.To.Sym = sym
p = pp.Prog(obj.ARET)
return p
}
// Branch is an unresolved branch.
type Branch struct {
P *obj.Prog // branch instruction
B *ssa.Block // target
}
// SSAGenState contains state needed during Prog generation.
type SSAGenState struct {
pp *Progs
// Branches remembers all the branch instructions we've seen
// and where they would like to go.
Branches []Branch
// bstart remembers where each block starts (indexed by block ID)
bstart []*obj.Prog
// 387 port: maps from SSE registers (REG_X?) to 387 registers (REG_F?)
SSEto387 map[int16]int16
// Some architectures require a 64-bit temporary for FP-related register shuffling. Examples include x86-387, PPC, and Sparc V8.
ScratchFpMem *Node
maxarg int64 // largest frame size for arguments to calls made by the function
// Map from GC safe points to liveness index, generated by
// liveness analysis.
livenessMap LivenessMap
// lineRunStart records the beginning of the current run of instructions
// within a single block sharing the same line number
// Used to move statement marks to the beginning of such runs.
lineRunStart *obj.Prog
// wasm: The number of values on the WebAssembly stack. This is only used as a safeguard.
OnWasmStackSkipped int
// Liveness index for the first function call in the final defer exit code
// path that we generated. All defer functions and args should be live at
// this point. This will be used to set the liveness for the deferreturn.
lastDeferLiveness LivenessIndex
}
// Prog appends a new Prog.
func (s *SSAGenState) Prog(as obj.As) *obj.Prog {
p := s.pp.Prog(as)
if ssa.LosesStmtMark(as) {
return p
}
// Float a statement start to the beginning of any same-line run.
// lineRunStart is reset at block boundaries, which appears to work well.
if s.lineRunStart == nil || s.lineRunStart.Pos.Line() != p.Pos.Line() {
s.lineRunStart = p
} else if p.Pos.IsStmt() == src.PosIsStmt {
s.lineRunStart.Pos = s.lineRunStart.Pos.WithIsStmt()
p.Pos = p.Pos.WithNotStmt()
}
return p
}
// Pc returns the current Prog.
func (s *SSAGenState) Pc() *obj.Prog {
return s.pp.next
}
// SetPos sets the current source position.
func (s *SSAGenState) SetPos(pos src.XPos) {
s.pp.pos = pos
}
// Br emits a single branch instruction and returns the instruction.
// Not all architectures need the returned instruction, but otherwise
// the boilerplate is common to all.
func (s *SSAGenState) Br(op obj.As, target *ssa.Block) *obj.Prog {
p := s.Prog(op)
p.To.Type = obj.TYPE_BRANCH
s.Branches = append(s.Branches, Branch{P: p, B: target})
return p
}
// DebugFriendlySetPosFrom adjusts Pos.IsStmt subject to heuristics
// that reduce "jumpy" line number churn when debugging.
// Spill/fill/copy instructions from the register allocator,
// phi functions, and instructions with a no-pos position
// are examples of instructions that can cause churn.
func (s *SSAGenState) DebugFriendlySetPosFrom(v *ssa.Value) {
switch v.Op {
case ssa.OpPhi, ssa.OpCopy, ssa.OpLoadReg, ssa.OpStoreReg:
// These are not statements
s.SetPos(v.Pos.WithNotStmt())
default:
p := v.Pos
if p != src.NoXPos {
// If the position is defined, update the position.
// Also convert default IsStmt to NotStmt; only
// explicit statement boundaries should appear
// in the generated code.
if p.IsStmt() != src.PosIsStmt {
p = p.WithNotStmt()
// Calls use the pos attached to v, but copy the statement mark from SSAGenState
}
s.SetPos(p)
} else {
s.SetPos(s.pp.pos.WithNotStmt())
}
}
}
// byXoffset implements sort.Interface for []*Node using Xoffset as the ordering.
type byXoffset []*Node
func (s byXoffset) Len() int { return len(s) }
func (s byXoffset) Less(i, j int) bool { return s[i].Xoffset < s[j].Xoffset }
func (s byXoffset) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
func emitStackObjects(e *ssafn, pp *Progs) {
var vars []*Node
for _, n := range e.curfn.Func.Dcl {
if livenessShouldTrack(n) && n.Name.Addrtaken() {
vars = append(vars, n)
}
}
if len(vars) == 0 {
return
}
// Sort variables from lowest to highest address.
sort.Sort(byXoffset(vars))
// Populate the stack object data.
// Format must match runtime/stack.go:stackObjectRecord.
x := e.curfn.Func.lsym.Func.StackObjects
off := 0
off = duintptr(x, off, uint64(len(vars)))
for _, v := range vars {
// Note: arguments and return values have non-negative Xoffset,
// in which case the offset is relative to argp.
// Locals have a negative Xoffset, in which case the offset is relative to varp.
off = duintptr(x, off, uint64(v.Xoffset))
if !typesym(v.Type).Siggen() {
e.Fatalf(v.Pos, "stack object's type symbol not generated for type %s", v.Type)
}
off = dsymptr(x, off, dtypesym(v.Type), 0)
}
// Emit a funcdata pointing at the stack object data.
p := pp.Prog(obj.AFUNCDATA)
Addrconst(&p.From, objabi.FUNCDATA_StackObjects)
p.To.Type = obj.TYPE_MEM
p.To.Name = obj.NAME_EXTERN
p.To.Sym = x
if debuglive != 0 {
for _, v := range vars {
Warnl(v.Pos, "stack object %v %s", v, v.Type.String())
}
}
}
// genssa appends entries to pp for each instruction in f.
func genssa(f *ssa.Func, pp *Progs) {
var s SSAGenState
e := f.Frontend().(*ssafn)
s.livenessMap = liveness(e, f, pp)
emitStackObjects(e, pp)
openDeferInfo := e.curfn.Func.lsym.Func.OpenCodedDeferInfo
if openDeferInfo != nil {
// This function uses open-coded defers -- write out the funcdata
// info that we computed at the end of genssa.
p := pp.Prog(obj.AFUNCDATA)
Addrconst(&p.From, objabi.FUNCDATA_OpenCodedDeferInfo)
p.To.Type = obj.TYPE_MEM
p.To.Name = obj.NAME_EXTERN
p.To.Sym = openDeferInfo
}
// Remember where each block starts.
s.bstart = make([]*obj.Prog, f.NumBlocks())
s.pp = pp
var progToValue map[*obj.Prog]*ssa.Value
var progToBlock map[*obj.Prog]*ssa.Block
var valueToProgAfter []*obj.Prog // The first Prog following computation of a value v; v is visible at this point.
if f.PrintOrHtmlSSA {
progToValue = make(map[*obj.Prog]*ssa.Value, f.NumValues())
progToBlock = make(map[*obj.Prog]*ssa.Block, f.NumBlocks())
f.Logf("genssa %s\n", f.Name)
progToBlock[s.pp.next] = f.Blocks[0]
}
if thearch.Use387 {
s.SSEto387 = map[int16]int16{}
}
s.ScratchFpMem = e.scratchFpMem
if Ctxt.Flag_locationlists {
if cap(f.Cache.ValueToProgAfter) < f.NumValues() {
f.Cache.ValueToProgAfter = make([]*obj.Prog, f.NumValues())
}
valueToProgAfter = f.Cache.ValueToProgAfter[:f.NumValues()]
for i := range valueToProgAfter {
valueToProgAfter[i] = nil
}
}
// If the very first instruction is not tagged as a statement,
// debuggers may attribute it to previous function in program.
firstPos := src.NoXPos
for _, v := range f.Entry.Values {
if v.Pos.IsStmt() == src.PosIsStmt {
firstPos = v.Pos
v.Pos = firstPos.WithDefaultStmt()
break
}
}
// inlMarks has an entry for each Prog that implements an inline mark.
// It maps from that Prog to the global inlining id of the inlined body
// which should unwind to this Prog's location.
var inlMarks map[*obj.Prog]int32
var inlMarkList []*obj.Prog
// inlMarksByPos maps from a (column 1) source position to the set of
// Progs that are in the set above and have that source position.
var inlMarksByPos map[src.XPos][]*obj.Prog
// Emit basic blocks
for i, b := range f.Blocks {
s.bstart[b.ID] = s.pp.next
s.lineRunStart = nil
// Attach a "default" liveness info. Normally this will be
// overwritten in the Values loop below for each Value. But
// for an empty block this will be used for its control
// instruction. We won't use the actual liveness map on a
// control instruction. Just mark it something that is
// preemptible, unless this function is "all unsafe".
s.pp.nextLive = LivenessIndex{-1, -1, allUnsafe(f)}
// Emit values in block
thearch.SSAMarkMoves(&s, b)
for _, v := range b.Values {
x := s.pp.next
s.DebugFriendlySetPosFrom(v)
switch v.Op {
case ssa.OpInitMem:
// memory arg needs no code
case ssa.OpArg:
// input args need no code
case ssa.OpSP, ssa.OpSB:
// nothing to do
case ssa.OpSelect0, ssa.OpSelect1:
// nothing to do
case ssa.OpGetG:
// nothing to do when there's a g register,
// and checkLower complains if there's not
case ssa.OpVarDef, ssa.OpVarLive, ssa.OpKeepAlive, ssa.OpVarKill:
// nothing to do; already used by liveness
case ssa.OpPhi:
CheckLoweredPhi(v)
case ssa.OpConvert:
// nothing to do; no-op conversion for liveness
if v.Args[0].Reg() != v.Reg() {
v.Fatalf("OpConvert should be a no-op: %s; %s", v.Args[0].LongString(), v.LongString())
}
case ssa.OpInlMark:
p := thearch.Ginsnop(s.pp)
if inlMarks == nil {
inlMarks = map[*obj.Prog]int32{}
inlMarksByPos = map[src.XPos][]*obj.Prog{}
}
inlMarks[p] = v.AuxInt32()
inlMarkList = append(inlMarkList, p)
pos := v.Pos.AtColumn1()
inlMarksByPos[pos] = append(inlMarksByPos[pos], p)
default:
// Attach this safe point to the next
// instruction.
s.pp.nextLive = s.livenessMap.Get(v)
// Remember the liveness index of the first defer call of
// the last defer exit
if v.Block.Func.LastDeferExit != nil && v == v.Block.Func.LastDeferExit {
s.lastDeferLiveness = s.pp.nextLive
}
// Special case for first line in function; move it to the start.
if firstPos != src.NoXPos {
s.SetPos(firstPos)
firstPos = src.NoXPos
}
// let the backend handle it
thearch.SSAGenValue(&s, v)
}
if Ctxt.Flag_locationlists {
valueToProgAfter[v.ID] = s.pp.next
}
if f.PrintOrHtmlSSA {
for ; x != s.pp.next; x = x.Link {
progToValue[x] = v
}
}
}
// If this is an empty infinite loop, stick a hardware NOP in there so that debuggers are less confused.
if s.bstart[b.ID] == s.pp.next && len(b.Succs) == 1 && b.Succs[0].Block() == b {
p := thearch.Ginsnop(s.pp)
p.Pos = p.Pos.WithIsStmt()
if b.Pos == src.NoXPos {
b.Pos = p.Pos // It needs a file, otherwise a no-file non-zero line causes confusion. See #35652.
if b.Pos == src.NoXPos {
b.Pos = pp.Text.Pos // Sometimes p.Pos is empty. See #35695.
}
}
b.Pos = b.Pos.WithBogusLine() // Debuggers are not good about infinite loops, force a change in line number
}
// Emit control flow instructions for block
var next *ssa.Block
if i < len(f.Blocks)-1 && Debug['N'] == 0 {
// If -N, leave next==nil so every block with successors
// ends in a JMP (except call blocks - plive doesn't like
// select{send,recv} followed by a JMP call). Helps keep
// line numbers for otherwise empty blocks.
next = f.Blocks[i+1]
}
x := s.pp.next
s.SetPos(b.Pos)
thearch.SSAGenBlock(&s, b, next)
if f.PrintOrHtmlSSA {
for ; x != s.pp.next; x = x.Link {
progToBlock[x] = b
}
}
}
if f.Blocks[len(f.Blocks)-1].Kind == ssa.BlockExit {
// We need the return address of a panic call to
// still be inside the function in question. So if
// it ends in a call which doesn't return, add a
// nop (which will never execute) after the call.
thearch.Ginsnop(pp)
}
if openDeferInfo != nil {
// When doing open-coded defers, generate a disconnected call to
// deferreturn and a return. This will be used to during panic
// recovery to unwind the stack and return back to the runtime.
s.pp.nextLive = s.lastDeferLiveness
gencallret(pp, Deferreturn)
}
if inlMarks != nil {
// We have some inline marks. Try to find other instructions we're
// going to emit anyway, and use those instructions instead of the
// inline marks.
for p := pp.Text; p != nil; p = p.Link {
if p.As == obj.ANOP || p.As == obj.AFUNCDATA || p.As == obj.APCDATA || p.As == obj.ATEXT || p.As == obj.APCALIGN || thearch.LinkArch.Family == sys.Wasm {
// Don't use 0-sized instructions as inline marks, because we need
// to identify inline mark instructions by pc offset.
// (Some of these instructions are sometimes zero-sized, sometimes not.
// We must not use anything that even might be zero-sized.)
// TODO: are there others?
continue
}
if _, ok := inlMarks[p]; ok {
// Don't use inline marks themselves. We don't know
// whether they will be zero-sized or not yet.
continue
}
pos := p.Pos.AtColumn1()
s := inlMarksByPos[pos]
if len(s) == 0 {
continue
}
for _, m := range s {
// We found an instruction with the same source position as
// some of the inline marks.
// Use this instruction instead.
p.Pos = p.Pos.WithIsStmt() // promote position to a statement
pp.curfn.Func.lsym.Func.AddInlMark(p, inlMarks[m])
// Make the inline mark a real nop, so it doesn't generate any code.
m.As = obj.ANOP
m.Pos = src.NoXPos
m.From = obj.Addr{}
m.To = obj.Addr{}
}
delete(inlMarksByPos, pos)
}
// Any unmatched inline marks now need to be added to the inlining tree (and will generate a nop instruction).
for _, p := range inlMarkList {
if p.As != obj.ANOP {
pp.curfn.Func.lsym.Func.AddInlMark(p, inlMarks[p])
}
}
}
if Ctxt.Flag_locationlists {
e.curfn.Func.DebugInfo = ssa.BuildFuncDebug(Ctxt, f, Debug_locationlist > 1, stackOffset)
bstart := s.bstart
// Note that at this moment, Prog.Pc is a sequence number; it's
// not a real PC until after assembly, so this mapping has to
// be done later.
e.curfn.Func.DebugInfo.GetPC = func(b, v ssa.ID) int64 {
switch v {
case ssa.BlockStart.ID:
if b == f.Entry.ID {
return 0 // Start at the very beginning, at the assembler-generated prologue.
// this should only happen for function args (ssa.OpArg)
}
return bstart[b].Pc
case ssa.BlockEnd.ID:
return e.curfn.Func.lsym.Size
default:
return valueToProgAfter[v].Pc
}
}
}
// Resolve branches, and relax DefaultStmt into NotStmt
for _, br := range s.Branches {
br.P.To.Val = s.bstart[br.B.ID]
if br.P.Pos.IsStmt() != src.PosIsStmt {
br.P.Pos = br.P.Pos.WithNotStmt()
} else if v0 := br.B.FirstPossibleStmtValue(); v0 != nil && v0.Pos.Line() == br.P.Pos.Line() && v0.Pos.IsStmt() == src.PosIsStmt {
br.P.Pos = br.P.Pos.WithNotStmt()
}
}
if e.log { // spew to stdout
filename := ""
for p := pp.Text; p != nil; p = p.Link {
if p.Pos.IsKnown() && p.InnermostFilename() != filename {
filename = p.InnermostFilename()
f.Logf("# %s\n", filename)
}
var s string
if v, ok := progToValue[p]; ok {
s = v.String()
} else if b, ok := progToBlock[p]; ok {
s = b.String()
} else {
s = " " // most value and branch strings are 2-3 characters long
}
f.Logf(" %-6s\t%.5d (%s)\t%s\n", s, p.Pc, p.InnermostLineNumber(), p.InstructionString())
}
}
if f.HTMLWriter != nil { // spew to ssa.html
var buf bytes.Buffer
buf.WriteString("<code>")
buf.WriteString("<dl class=\"ssa-gen\">")
filename := ""
for p := pp.Text; p != nil; p = p.Link {
// Don't spam every line with the file name, which is often huge.
// Only print changes, and "unknown" is not a change.
if p.Pos.IsKnown() && p.InnermostFilename() != filename {
filename = p.InnermostFilename()
buf.WriteString("<dt class=\"ssa-prog-src\"></dt><dd class=\"ssa-prog\">")
buf.WriteString(html.EscapeString("# " + filename))
buf.WriteString("</dd>")
}
buf.WriteString("<dt class=\"ssa-prog-src\">")
if v, ok := progToValue[p]; ok {
buf.WriteString(v.HTML())
} else if b, ok := progToBlock[p]; ok {
buf.WriteString("<b>" + b.HTML() + "</b>")
}
buf.WriteString("</dt>")
buf.WriteString("<dd class=\"ssa-prog\">")
buf.WriteString(fmt.Sprintf("%.5d <span class=\"l%v line-number\">(%s)</span> %s", p.Pc, p.InnermostLineNumber(), p.InnermostLineNumberHTML(), html.EscapeString(p.InstructionString())))
buf.WriteString("</dd>")
}
buf.WriteString("</dl>")
buf.WriteString("</code>")
f.HTMLWriter.WriteColumn("genssa", "genssa", "ssa-prog", buf.String())
}
defframe(&s, e)
f.HTMLWriter.Close()
f.HTMLWriter = nil
}
func defframe(s *SSAGenState, e *ssafn) {
pp := s.pp
frame := Rnd(s.maxarg+e.stksize, int64(Widthreg))
if thearch.PadFrame != nil {
frame = thearch.PadFrame(frame)
}
// Fill in argument and frame size.
pp.Text.To.Type = obj.TYPE_TEXTSIZE
pp.Text.To.Val = int32(Rnd(e.curfn.Type.ArgWidth(), int64(Widthreg)))
pp.Text.To.Offset = frame
// Insert code to zero ambiguously live variables so that the
// garbage collector only sees initialized values when it
// looks for pointers.
p := pp.Text
var lo, hi int64
// Opaque state for backend to use. Current backends use it to
// keep track of which helper registers have been zeroed.
var state uint32
// Iterate through declarations. They are sorted in decreasing Xoffset order.
for _, n := range e.curfn.Func.Dcl {
if !n.Name.Needzero() {
continue
}
if n.Class() != PAUTO {
e.Fatalf(n.Pos, "needzero class %d", n.Class())
}
if n.Type.Size()%int64(Widthptr) != 0 || n.Xoffset%int64(Widthptr) != 0 || n.Type.Size() == 0 {
e.Fatalf(n.Pos, "var %L has size %d offset %d", n, n.Type.Size(), n.Xoffset)
}
if lo != hi && n.Xoffset+n.Type.Size() >= lo-int64(2*Widthreg) {
// Merge with range we already have.
lo = n.Xoffset
continue
}
// Zero old range
p = thearch.ZeroRange(pp, p, frame+lo, hi-lo, &state)
// Set new range.
lo = n.Xoffset
hi = lo + n.Type.Size()
}
// Zero final range.
thearch.ZeroRange(pp, p, frame+lo, hi-lo, &state)
}
// For generating consecutive jump instructions to model a specific branching
type IndexJump struct {
Jump obj.As
Index int
}
func (s *SSAGenState) oneJump(b *ssa.Block, jump *IndexJump) {
p := s.Br(jump.Jump, b.Succs[jump.Index].Block())
p.Pos = b.Pos
}
// CombJump generates combinational instructions (2 at present) for a block jump,
// thereby the behaviour of non-standard condition codes could be simulated
func (s *SSAGenState) CombJump(b, next *ssa.Block, jumps *[2][2]IndexJump) {
switch next {
case b.Succs[0].Block():
s.oneJump(b, &jumps[0][0])
s.oneJump(b, &jumps[0][1])
case b.Succs[1].Block():
s.oneJump(b, &jumps[1][0])
s.oneJump(b, &jumps[1][1])
default:
var q *obj.Prog
if b.Likely != ssa.BranchUnlikely {
s.oneJump(b, &jumps[1][0])
s.oneJump(b, &jumps[1][1])
q = s.Br(obj.AJMP, b.Succs[1].Block())
} else {
s.oneJump(b, &jumps[0][0])
s.oneJump(b, &jumps[0][1])
q = s.Br(obj.AJMP, b.Succs[0].Block())
}
q.Pos = b.Pos
}
}
// AddAux adds the offset in the aux fields (AuxInt and Aux) of v to a.
func AddAux(a *obj.Addr, v *ssa.Value) {
AddAux2(a, v, v.AuxInt)
}
func AddAux2(a *obj.Addr, v *ssa.Value, offset int64) {
if a.Type != obj.TYPE_MEM && a.Type != obj.TYPE_ADDR {
v.Fatalf("bad AddAux addr %v", a)
}
// add integer offset
a.Offset += offset
// If no additional symbol offset, we're done.
if v.Aux == nil {
return
}
// Add symbol's offset from its base register.
switch n := v.Aux.(type) {
case *obj.LSym:
a.Name = obj.NAME_EXTERN
a.Sym = n
case *Node:
if n.Class() == PPARAM || n.Class() == PPARAMOUT {
a.Name = obj.NAME_PARAM
a.Sym = n.Orig.Sym.Linksym()
a.Offset += n.Xoffset
break
}
a.Name = obj.NAME_AUTO
a.Sym = n.Sym.Linksym()
a.Offset += n.Xoffset
default:
v.Fatalf("aux in %s not implemented %#v", v, v.Aux)
}
}
// extendIndex extends v to a full int width.
// panic with the given kind if v does not fit in an int (only on 32-bit archs).
func (s *state) extendIndex(idx, len *ssa.Value, kind ssa.BoundsKind, bounded bool) *ssa.Value {
size := idx.Type.Size()
if size == s.config.PtrSize {
return idx
}
if size > s.config.PtrSize {
// truncate 64-bit indexes on 32-bit pointer archs. Test the
// high word and branch to out-of-bounds failure if it is not 0.
var lo *ssa.Value
if idx.Type.IsSigned() {
lo = s.newValue1(ssa.OpInt64Lo, types.Types[TINT], idx)
} else {
lo = s.newValue1(ssa.OpInt64Lo, types.Types[TUINT], idx)
}
if bounded || Debug['B'] != 0 {
return lo
}
bNext := s.f.NewBlock(ssa.BlockPlain)
bPanic := s.f.NewBlock(ssa.BlockExit)
hi := s.newValue1(ssa.OpInt64Hi, types.Types[TUINT32], idx)
cmp := s.newValue2(ssa.OpEq32, types.Types[TBOOL], hi, s.constInt32(types.Types[TUINT32], 0))
if !idx.Type.IsSigned() {
switch kind {
case ssa.BoundsIndex:
kind = ssa.BoundsIndexU
case ssa.BoundsSliceAlen:
kind = ssa.BoundsSliceAlenU
case ssa.BoundsSliceAcap:
kind = ssa.BoundsSliceAcapU
case ssa.BoundsSliceB:
kind = ssa.BoundsSliceBU
case ssa.BoundsSlice3Alen:
kind = ssa.BoundsSlice3AlenU
case ssa.BoundsSlice3Acap:
kind = ssa.BoundsSlice3AcapU
case ssa.BoundsSlice3B:
kind = ssa.BoundsSlice3BU
case ssa.BoundsSlice3C:
kind = ssa.BoundsSlice3CU
}
}
b := s.endBlock()
b.Kind = ssa.BlockIf
b.SetControl(cmp)
b.Likely = ssa.BranchLikely
b.AddEdgeTo(bNext)
b.AddEdgeTo(bPanic)
s.startBlock(bPanic)
mem := s.newValue4I(ssa.OpPanicExtend, types.TypeMem, int64(kind), hi, lo, len, s.mem())
s.endBlock().SetControl(mem)
s.startBlock(bNext)
return lo
}
// Extend value to the required size
var op ssa.Op
if idx.Type.IsSigned() {
switch 10*size + s.config.PtrSize {
case 14:
op = ssa.OpSignExt8to32
case 18:
op = ssa.OpSignExt8to64
case 24:
op = ssa.OpSignExt16to32
case 28:
op = ssa.OpSignExt16to64
case 48:
op = ssa.OpSignExt32to64
default:
s.Fatalf("bad signed index extension %s", idx.Type)
}
} else {
switch 10*size + s.config.PtrSize {
case 14:
op = ssa.OpZeroExt8to32
case 18:
op = ssa.OpZeroExt8to64
case 24:
op = ssa.OpZeroExt16to32
case 28:
op = ssa.OpZeroExt16to64
case 48:
op = ssa.OpZeroExt32to64
default:
s.Fatalf("bad unsigned index extension %s", idx.Type)
}
}
return s.newValue1(op, types.Types[TINT], idx)
}
// CheckLoweredPhi checks that regalloc and stackalloc correctly handled phi values.
// Called during ssaGenValue.
func CheckLoweredPhi(v *ssa.Value) {
if v.Op != ssa.OpPhi {
v.Fatalf("CheckLoweredPhi called with non-phi value: %v", v.LongString())
}
if v.Type.IsMemory() {
return
}
f := v.Block.Func
loc := f.RegAlloc[v.ID]
for _, a := range v.Args {
if aloc := f.RegAlloc[a.ID]; aloc != loc { // TODO: .Equal() instead?
v.Fatalf("phi arg at different location than phi: %v @ %s, but arg %v @ %s\n%s\n", v, loc, a, aloc, v.Block.Func)
}
}
}
// CheckLoweredGetClosurePtr checks that v is the first instruction in the function's entry block.
// The output of LoweredGetClosurePtr is generally hardwired to the correct register.
// That register contains the closure pointer on closure entry.
func CheckLoweredGetClosurePtr(v *ssa.Value) {
entry := v.Block.Func.Entry
if entry != v.Block || entry.Values[0] != v {
Fatalf("in %s, badly placed LoweredGetClosurePtr: %v %v", v.Block.Func.Name, v.Block, v)
}
}
// AutoVar returns a *Node and int64 representing the auto variable and offset within it
// where v should be spilled.
func AutoVar(v *ssa.Value) (*Node, int64) {
loc := v.Block.Func.RegAlloc[v.ID].(ssa.LocalSlot)
if v.Type.Size() > loc.Type.Size() {
v.Fatalf("spill/restore type %s doesn't fit in slot type %s", v.Type, loc.Type)
}
return loc.N.(*Node), loc.Off
}
func AddrAuto(a *obj.Addr, v *ssa.Value) {
n, off := AutoVar(v)
a.Type = obj.TYPE_MEM
a.Sym = n.Sym.Linksym()
a.Reg = int16(thearch.REGSP)
a.Offset = n.Xoffset + off
if n.Class() == PPARAM || n.Class() == PPARAMOUT {
a.Name = obj.NAME_PARAM
} else {
a.Name = obj.NAME_AUTO
}
}
func (s *SSAGenState) AddrScratch(a *obj.Addr) {
if s.ScratchFpMem == nil {
panic("no scratch memory available; forgot to declare usesScratch for Op?")
}
a.Type = obj.TYPE_MEM
a.Name = obj.NAME_AUTO
a.Sym = s.ScratchFpMem.Sym.Linksym()
a.Reg = int16(thearch.REGSP)
a.Offset = s.ScratchFpMem.Xoffset
}
// Call returns a new CALL instruction for the SSA value v.
// It uses PrepareCall to prepare the call.
func (s *SSAGenState) Call(v *ssa.Value) *obj.Prog {
pPosIsStmt := s.pp.pos.IsStmt() // The statement-ness fo the call comes from ssaGenState
s.PrepareCall(v)
p := s.Prog(obj.ACALL)
if pPosIsStmt == src.PosIsStmt {
p.Pos = v.Pos.WithIsStmt()
} else {
p.Pos = v.Pos.WithNotStmt()
}
if sym, ok := v.Aux.(*obj.LSym); ok {
p.To.Type = obj.TYPE_MEM
p.To.Name = obj.NAME_EXTERN
p.To.Sym = sym
} else {
// TODO(mdempsky): Can these differences be eliminated?
switch thearch.LinkArch.Family {
case sys.AMD64, sys.I386, sys.PPC64, sys.RISCV64, sys.S390X, sys.Wasm:
p.To.Type = obj.TYPE_REG
case sys.ARM, sys.ARM64, sys.MIPS, sys.MIPS64:
p.To.Type = obj.TYPE_MEM
default:
Fatalf("unknown indirect call family")
}
p.To.Reg = v.Args[0].Reg()
}
return p
}
// PrepareCall prepares to emit a CALL instruction for v and does call-related bookkeeping.
// It must be called immediately before emitting the actual CALL instruction,
// since it emits PCDATA for the stack map at the call (calls are safe points).
func (s *SSAGenState) PrepareCall(v *ssa.Value) {
idx := s.livenessMap.Get(v)
if !idx.StackMapValid() {
// See Liveness.hasStackMap.
if sym, _ := v.Aux.(*obj.LSym); !(sym == typedmemclr || sym == typedmemmove) {
Fatalf("missing stack map index for %v", v.LongString())
}
}
if sym, _ := v.Aux.(*obj.LSym); sym == Deferreturn {
// Deferred calls will appear to be returning to
// the CALL deferreturn(SB) that we are about to emit.
// However, the stack trace code will show the line
// of the instruction byte before the return PC.
// To avoid that being an unrelated instruction,
// insert an actual hardware NOP that will have the right line number.
// This is different from obj.ANOP, which is a virtual no-op
// that doesn't make it into the instruction stream.
thearch.Ginsnopdefer(s.pp)
}
if sym, ok := v.Aux.(*obj.LSym); ok {
// Record call graph information for nowritebarrierrec
// analysis.
if nowritebarrierrecCheck != nil {
nowritebarrierrecCheck.recordCall(s.pp.curfn, sym, v.Pos)
}
}
if s.maxarg < v.AuxInt {
s.maxarg = v.AuxInt
}
}
// UseArgs records the fact that an instruction needs a certain amount of
// callee args space for its use.
func (s *SSAGenState) UseArgs(n int64) {
if s.maxarg < n {
s.maxarg = n
}
}
// fieldIdx finds the index of the field referred to by the ODOT node n.
func fieldIdx(n *Node) int {
t := n.Left.Type
f := n.Sym
if !t.IsStruct() {
panic("ODOT's LHS is not a struct")
}
var i int
for _, t1 := range t.Fields().Slice() {
if t1.Sym != f {
i++
continue
}
if t1.Offset != n.Xoffset {
panic("field offset doesn't match")
}
return i
}
panic(fmt.Sprintf("can't find field in expr %v\n", n))
// TODO: keep the result of this function somewhere in the ODOT Node
// so we don't have to recompute it each time we need it.
}
// ssafn holds frontend information about a function that the backend is processing.
// It also exports a bunch of compiler services for the ssa backend.
type ssafn struct {
curfn *Node
strings map[string]*obj.LSym // map from constant string to data symbols
scratchFpMem *Node // temp for floating point register / memory moves on some architectures
stksize int64 // stack size for current frame
stkptrsize int64 // prefix of stack containing pointers
log bool // print ssa debug to the stdout
}
// StringData returns a symbol which
// is the data component of a global string constant containing s.
func (e *ssafn) StringData(s string) *obj.LSym {
if aux, ok := e.strings[s]; ok {
return aux
}
if e.strings == nil {
e.strings = make(map[string]*obj.LSym)
}
data := stringsym(e.curfn.Pos, s)
e.strings[s] = data
return data
}
func (e *ssafn) Auto(pos src.XPos, t *types.Type) ssa.GCNode {
n := tempAt(pos, e.curfn, t) // Note: adds new auto to e.curfn.Func.Dcl list
return n
}
func (e *ssafn) SplitString(name ssa.LocalSlot) (ssa.LocalSlot, ssa.LocalSlot) {
n := name.N.(*Node)
ptrType := types.NewPtr(types.Types[TUINT8])
lenType := types.Types[TINT]
if n.Class() == PAUTO && !n.Name.Addrtaken() {
// Split this string up into two separate variables.
p := e.splitSlot(&name, ".ptr", 0, ptrType)
l := e.splitSlot(&name, ".len", ptrType.Size(), lenType)
return p, l
}
// Return the two parts of the larger variable.
return ssa.LocalSlot{N: n, Type: ptrType, Off: name.Off}, ssa.LocalSlot{N: n, Type: lenType, Off: name.Off + int64(Widthptr)}
}
func (e *ssafn) SplitInterface(name ssa.LocalSlot) (ssa.LocalSlot, ssa.LocalSlot) {
n := name.N.(*Node)
u := types.Types[TUINTPTR]
t := types.NewPtr(types.Types[TUINT8])
if n.Class() == PAUTO && !n.Name.Addrtaken() {
// Split this interface up into two separate variables.
f := ".itab"
if n.Type.IsEmptyInterface() {
f = ".type"
}
c := e.splitSlot(&name, f, 0, u) // see comment in plive.go:onebitwalktype1.
d := e.splitSlot(&name, ".data", u.Size(), t)
return c, d
}
// Return the two parts of the larger variable.
return ssa.LocalSlot{N: n, Type: u, Off: name.Off}, ssa.LocalSlot{N: n, Type: t, Off: name.Off + int64(Widthptr)}
}
func (e *ssafn) SplitSlice(name ssa.LocalSlot) (ssa.LocalSlot, ssa.LocalSlot, ssa.LocalSlot) {
n := name.N.(*Node)
ptrType := types.NewPtr(name.Type.Elem())
lenType := types.Types[TINT]
if n.Class() == PAUTO && !n.Name.Addrtaken() {
// Split this slice up into three separate variables.
p := e.splitSlot(&name, ".ptr", 0, ptrType)
l := e.splitSlot(&name, ".len", ptrType.Size(), lenType)
c := e.splitSlot(&name, ".cap", ptrType.Size()+lenType.Size(), lenType)
return p, l, c
}
// Return the three parts of the larger variable.
return ssa.LocalSlot{N: n, Type: ptrType, Off: name.Off},
ssa.LocalSlot{N: n, Type: lenType, Off: name.Off + int64(Widthptr)},
ssa.LocalSlot{N: n, Type: lenType, Off: name.Off + int64(2*Widthptr)}
}
func (e *ssafn) SplitComplex(name ssa.LocalSlot) (ssa.LocalSlot, ssa.LocalSlot) {
n := name.N.(*Node)
s := name.Type.Size() / 2
var t *types.Type
if s == 8 {
t = types.Types[TFLOAT64]
} else {
t = types.Types[TFLOAT32]
}
if n.Class() == PAUTO && !n.Name.Addrtaken() {
// Split this complex up into two separate variables.
r := e.splitSlot(&name, ".real", 0, t)
i := e.splitSlot(&name, ".imag", t.Size(), t)
return r, i
}
// Return the two parts of the larger variable.
return ssa.LocalSlot{N: n, Type: t, Off: name.Off}, ssa.LocalSlot{N: n, Type: t, Off: name.Off + s}
}
func (e *ssafn) SplitInt64(name ssa.LocalSlot) (ssa.LocalSlot, ssa.LocalSlot) {
n := name.N.(*Node)
var t *types.Type
if name.Type.IsSigned() {
t = types.Types[TINT32]
} else {
t = types.Types[TUINT32]
}
if n.Class() == PAUTO && !n.Name.Addrtaken() {
// Split this int64 up into two separate variables.
if thearch.LinkArch.ByteOrder == binary.BigEndian {
return e.splitSlot(&name, ".hi", 0, t), e.splitSlot(&name, ".lo", t.Size(), types.Types[TUINT32])
}
return e.splitSlot(&name, ".hi", t.Size(), t), e.splitSlot(&name, ".lo", 0, types.Types[TUINT32])
}
// Return the two parts of the larger variable.
if thearch.LinkArch.ByteOrder == binary.BigEndian {
return ssa.LocalSlot{N: n, Type: t, Off: name.Off}, ssa.LocalSlot{N: n, Type: types.Types[TUINT32], Off: name.Off + 4}
}
return ssa.LocalSlot{N: n, Type: t, Off: name.Off + 4}, ssa.LocalSlot{N: n, Type: types.Types[TUINT32], Off: name.Off}
}
func (e *ssafn) SplitStruct(name ssa.LocalSlot, i int) ssa.LocalSlot {
n := name.N.(*Node)
st := name.Type
ft := st.FieldType(i)
var offset int64
for f := 0; f < i; f++ {
offset += st.FieldType(f).Size()
}
if n.Class() == PAUTO && !n.Name.Addrtaken() {
// Note: the _ field may appear several times. But
// have no fear, identically-named but distinct Autos are
// ok, albeit maybe confusing for a debugger.
return e.splitSlot(&name, "."+st.FieldName(i), offset, ft)
}
return ssa.LocalSlot{N: n, Type: ft, Off: name.Off + st.FieldOff(i)}
}
func (e *ssafn) SplitArray(name ssa.LocalSlot) ssa.LocalSlot {
n := name.N.(*Node)
at := name.Type
if at.NumElem() != 1 {
e.Fatalf(n.Pos, "bad array size")
}
et := at.Elem()
if n.Class() == PAUTO && !n.Name.Addrtaken() {
return e.splitSlot(&name, "[0]", 0, et)
}
return ssa.LocalSlot{N: n, Type: et, Off: name.Off}
}
func (e *ssafn) DerefItab(it *obj.LSym, offset int64) *obj.LSym {
return itabsym(it, offset)
}
// splitSlot returns a slot representing the data of parent starting at offset.
func (e *ssafn) splitSlot(parent *ssa.LocalSlot, suffix string, offset int64, t *types.Type) ssa.LocalSlot {
s := &types.Sym{Name: parent.N.(*Node).Sym.Name + suffix, Pkg: localpkg}
n := &Node{
Name: new(Name),
Op: ONAME,
Pos: parent.N.(*Node).Pos,
}
n.Orig = n
s.Def = asTypesNode(n)
asNode(s.Def).Name.SetUsed(true)
n.Sym = s
n.Type = t
n.SetClass(PAUTO)
n.Esc = EscNever
n.Name.Curfn = e.curfn
e.curfn.Func.Dcl = append(e.curfn.Func.Dcl, n)
dowidth(t)
return ssa.LocalSlot{N: n, Type: t, Off: 0, SplitOf: parent, SplitOffset: offset}
}
func (e *ssafn) CanSSA(t *types.Type) bool {
return canSSAType(t)
}
func (e *ssafn) Line(pos src.XPos) string {
return linestr(pos)
}
// Log logs a message from the compiler.
func (e *ssafn) Logf(msg string, args ...interface{}) {
if e.log {
fmt.Printf(msg, args...)
}
}
func (e *ssafn) Log() bool {
return e.log
}
// Fatal reports a compiler error and exits.
func (e *ssafn) Fatalf(pos src.XPos, msg string, args ...interface{}) {
lineno = pos
nargs := append([]interface{}{e.curfn.funcname()}, args...)
Fatalf("'%s': "+msg, nargs...)
}
// Warnl reports a "warning", which is usually flag-triggered
// logging output for the benefit of tests.
func (e *ssafn) Warnl(pos src.XPos, fmt_ string, args ...interface{}) {
Warnl(pos, fmt_, args...)
}
func (e *ssafn) Debug_checknil() bool {
return Debug_checknil != 0
}
func (e *ssafn) UseWriteBarrier() bool {
return use_writebarrier
}
func (e *ssafn) Syslook(name string) *obj.LSym {
switch name {
case "goschedguarded":
return goschedguarded
case "writeBarrier":
return writeBarrier
case "gcWriteBarrier":
return gcWriteBarrier
case "typedmemmove":
return typedmemmove
case "typedmemclr":
return typedmemclr
}
e.Fatalf(src.NoXPos, "unknown Syslook func %v", name)
return nil
}
func (e *ssafn) SetWBPos(pos src.XPos) {
e.curfn.Func.setWBPos(pos)
}
func (n *Node) Typ() *types.Type {
return n.Type
}
func (n *Node) StorageClass() ssa.StorageClass {
switch n.Class() {
case PPARAM:
return ssa.ClassParam
case PPARAMOUT:
return ssa.ClassParamOut
case PAUTO:
return ssa.ClassAuto
default:
Fatalf("untranslatable storage class for %v: %s", n, n.Class())
return 0
}
}
func clobberBase(n *Node) *Node {
if n.Op == ODOT && n.Left.Type.NumFields() == 1 {
return clobberBase(n.Left)
}
if n.Op == OINDEX && n.Left.Type.IsArray() && n.Left.Type.NumElem() == 1 {
return clobberBase(n.Left)
}
return n
}