blob: 10f02fc9871f35a315f2f6e58d3262c643f0968b [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 ssagen
import (
"bufio"
"bytes"
"cmd/compile/internal/abi"
"encoding/binary"
"fmt"
"go/constant"
"html"
"internal/buildcfg"
"os"
"path/filepath"
"sort"
"strings"
"cmd/compile/internal/base"
"cmd/compile/internal/ir"
"cmd/compile/internal/liveness"
"cmd/compile/internal/objw"
"cmd/compile/internal/reflectdata"
"cmd/compile/internal/ssa"
"cmd/compile/internal/staticdata"
"cmd/compile/internal/typecheck"
"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 ssaDir string // optional destination for ssa dump file
var ssaDumpStdout bool // whether to dump to stdout
var ssaDumpCFG string // generate CFGs for these phases
const ssaDumpFile = "ssa.html"
// ssaDumpInlined holds all inlined functions when ssaDump contains a function name.
var ssaDumpInlined []*ir.Func
func DumpInline(fn *ir.Func) {
if ssaDump != "" && ssaDump == ir.FuncName(fn) {
ssaDumpInlined = append(ssaDumpInlined, fn)
}
}
func InitEnv() {
ssaDump = os.Getenv("GOSSAFUNC")
ssaDir = os.Getenv("GOSSADIR")
if ssaDump != "" {
if strings.HasSuffix(ssaDump, "+") {
ssaDump = ssaDump[:len(ssaDump)-1]
ssaDumpStdout = true
}
spl := strings.Split(ssaDump, ":")
if len(spl) > 1 {
ssaDump = spl[0]
ssaDumpCFG = spl[1]
}
}
}
func InitConfig() {
types_ := ssa.NewTypes()
if Arch.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[types.TINTER]) // *interface{}
_ = types.NewPtr(types.NewPtr(types.Types[types.TSTRING])) // **string
_ = types.NewPtr(types.NewSlice(types.Types[types.TINTER])) // *[]interface{}
_ = types.NewPtr(types.NewPtr(types.ByteType)) // **byte
_ = types.NewPtr(types.NewSlice(types.ByteType)) // *[]byte
_ = types.NewPtr(types.NewSlice(types.Types[types.TSTRING])) // *[]string
_ = types.NewPtr(types.NewPtr(types.NewPtr(types.Types[types.TUINT8]))) // ***uint8
_ = types.NewPtr(types.Types[types.TINT16]) // *int16
_ = types.NewPtr(types.Types[types.TINT64]) // *int64
_ = types.NewPtr(types.ErrorType) // *error
types.NewPtrCacheEnabled = false
ssaConfig = ssa.NewConfig(base.Ctxt.Arch.Name, *types_, base.Ctxt, base.Flag.N == 0)
ssaConfig.SoftFloat = Arch.SoftFloat
ssaConfig.Race = base.Flag.Race
ssaCaches = make([]ssa.Cache, base.Flag.LowerC)
// Set up some runtime functions we'll need to call.
ir.Syms.AssertE2I = typecheck.LookupRuntimeFunc("assertE2I")
ir.Syms.AssertE2I2 = typecheck.LookupRuntimeFunc("assertE2I2")
ir.Syms.AssertI2I = typecheck.LookupRuntimeFunc("assertI2I")
ir.Syms.AssertI2I2 = typecheck.LookupRuntimeFunc("assertI2I2")
ir.Syms.Deferproc = typecheck.LookupRuntimeFunc("deferproc")
ir.Syms.DeferprocStack = typecheck.LookupRuntimeFunc("deferprocStack")
ir.Syms.Deferreturn = typecheck.LookupRuntimeFunc("deferreturn")
ir.Syms.Duffcopy = typecheck.LookupRuntimeFunc("duffcopy")
ir.Syms.Duffzero = typecheck.LookupRuntimeFunc("duffzero")
ir.Syms.GCWriteBarrier = typecheck.LookupRuntimeFunc("gcWriteBarrier")
ir.Syms.Goschedguarded = typecheck.LookupRuntimeFunc("goschedguarded")
ir.Syms.Growslice = typecheck.LookupRuntimeFunc("growslice")
ir.Syms.Msanread = typecheck.LookupRuntimeFunc("msanread")
ir.Syms.Msanwrite = typecheck.LookupRuntimeFunc("msanwrite")
ir.Syms.Msanmove = typecheck.LookupRuntimeFunc("msanmove")
ir.Syms.Newobject = typecheck.LookupRuntimeFunc("newobject")
ir.Syms.Newproc = typecheck.LookupRuntimeFunc("newproc")
ir.Syms.Panicdivide = typecheck.LookupRuntimeFunc("panicdivide")
ir.Syms.PanicdottypeE = typecheck.LookupRuntimeFunc("panicdottypeE")
ir.Syms.PanicdottypeI = typecheck.LookupRuntimeFunc("panicdottypeI")
ir.Syms.Panicnildottype = typecheck.LookupRuntimeFunc("panicnildottype")
ir.Syms.Panicoverflow = typecheck.LookupRuntimeFunc("panicoverflow")
ir.Syms.Panicshift = typecheck.LookupRuntimeFunc("panicshift")
ir.Syms.Raceread = typecheck.LookupRuntimeFunc("raceread")
ir.Syms.Racereadrange = typecheck.LookupRuntimeFunc("racereadrange")
ir.Syms.Racewrite = typecheck.LookupRuntimeFunc("racewrite")
ir.Syms.Racewriterange = typecheck.LookupRuntimeFunc("racewriterange")
ir.Syms.X86HasPOPCNT = typecheck.LookupRuntimeVar("x86HasPOPCNT") // bool
ir.Syms.X86HasSSE41 = typecheck.LookupRuntimeVar("x86HasSSE41") // bool
ir.Syms.X86HasFMA = typecheck.LookupRuntimeVar("x86HasFMA") // bool
ir.Syms.ARMHasVFPv4 = typecheck.LookupRuntimeVar("armHasVFPv4") // bool
ir.Syms.ARM64HasATOMICS = typecheck.LookupRuntimeVar("arm64HasATOMICS") // bool
ir.Syms.Staticuint64s = typecheck.LookupRuntimeVar("staticuint64s")
ir.Syms.Typedmemclr = typecheck.LookupRuntimeFunc("typedmemclr")
ir.Syms.Typedmemmove = typecheck.LookupRuntimeFunc("typedmemmove")
ir.Syms.Udiv = typecheck.LookupRuntimeVar("udiv") // asm func with special ABI
ir.Syms.WriteBarrier = typecheck.LookupRuntimeVar("writeBarrier") // struct { bool; ... }
ir.Syms.Zerobase = typecheck.LookupRuntimeVar("zerobase")
// asm funcs with special ABI
if base.Ctxt.Arch.Name == "amd64" {
GCWriteBarrierReg = map[int16]*obj.LSym{
x86.REG_AX: typecheck.LookupRuntimeFunc("gcWriteBarrier"),
x86.REG_CX: typecheck.LookupRuntimeFunc("gcWriteBarrierCX"),
x86.REG_DX: typecheck.LookupRuntimeFunc("gcWriteBarrierDX"),
x86.REG_BX: typecheck.LookupRuntimeFunc("gcWriteBarrierBX"),
x86.REG_BP: typecheck.LookupRuntimeFunc("gcWriteBarrierBP"),
x86.REG_SI: typecheck.LookupRuntimeFunc("gcWriteBarrierSI"),
x86.REG_R8: typecheck.LookupRuntimeFunc("gcWriteBarrierR8"),
x86.REG_R9: typecheck.LookupRuntimeFunc("gcWriteBarrierR9"),
}
}
if Arch.LinkArch.Family == sys.Wasm {
BoundsCheckFunc[ssa.BoundsIndex] = typecheck.LookupRuntimeFunc("goPanicIndex")
BoundsCheckFunc[ssa.BoundsIndexU] = typecheck.LookupRuntimeFunc("goPanicIndexU")
BoundsCheckFunc[ssa.BoundsSliceAlen] = typecheck.LookupRuntimeFunc("goPanicSliceAlen")
BoundsCheckFunc[ssa.BoundsSliceAlenU] = typecheck.LookupRuntimeFunc("goPanicSliceAlenU")
BoundsCheckFunc[ssa.BoundsSliceAcap] = typecheck.LookupRuntimeFunc("goPanicSliceAcap")
BoundsCheckFunc[ssa.BoundsSliceAcapU] = typecheck.LookupRuntimeFunc("goPanicSliceAcapU")
BoundsCheckFunc[ssa.BoundsSliceB] = typecheck.LookupRuntimeFunc("goPanicSliceB")
BoundsCheckFunc[ssa.BoundsSliceBU] = typecheck.LookupRuntimeFunc("goPanicSliceBU")
BoundsCheckFunc[ssa.BoundsSlice3Alen] = typecheck.LookupRuntimeFunc("goPanicSlice3Alen")
BoundsCheckFunc[ssa.BoundsSlice3AlenU] = typecheck.LookupRuntimeFunc("goPanicSlice3AlenU")
BoundsCheckFunc[ssa.BoundsSlice3Acap] = typecheck.LookupRuntimeFunc("goPanicSlice3Acap")
BoundsCheckFunc[ssa.BoundsSlice3AcapU] = typecheck.LookupRuntimeFunc("goPanicSlice3AcapU")
BoundsCheckFunc[ssa.BoundsSlice3B] = typecheck.LookupRuntimeFunc("goPanicSlice3B")
BoundsCheckFunc[ssa.BoundsSlice3BU] = typecheck.LookupRuntimeFunc("goPanicSlice3BU")
BoundsCheckFunc[ssa.BoundsSlice3C] = typecheck.LookupRuntimeFunc("goPanicSlice3C")
BoundsCheckFunc[ssa.BoundsSlice3CU] = typecheck.LookupRuntimeFunc("goPanicSlice3CU")
BoundsCheckFunc[ssa.BoundsConvert] = typecheck.LookupRuntimeFunc("goPanicSliceConvert")
} else {
BoundsCheckFunc[ssa.BoundsIndex] = typecheck.LookupRuntimeFunc("panicIndex")
BoundsCheckFunc[ssa.BoundsIndexU] = typecheck.LookupRuntimeFunc("panicIndexU")
BoundsCheckFunc[ssa.BoundsSliceAlen] = typecheck.LookupRuntimeFunc("panicSliceAlen")
BoundsCheckFunc[ssa.BoundsSliceAlenU] = typecheck.LookupRuntimeFunc("panicSliceAlenU")
BoundsCheckFunc[ssa.BoundsSliceAcap] = typecheck.LookupRuntimeFunc("panicSliceAcap")
BoundsCheckFunc[ssa.BoundsSliceAcapU] = typecheck.LookupRuntimeFunc("panicSliceAcapU")
BoundsCheckFunc[ssa.BoundsSliceB] = typecheck.LookupRuntimeFunc("panicSliceB")
BoundsCheckFunc[ssa.BoundsSliceBU] = typecheck.LookupRuntimeFunc("panicSliceBU")
BoundsCheckFunc[ssa.BoundsSlice3Alen] = typecheck.LookupRuntimeFunc("panicSlice3Alen")
BoundsCheckFunc[ssa.BoundsSlice3AlenU] = typecheck.LookupRuntimeFunc("panicSlice3AlenU")
BoundsCheckFunc[ssa.BoundsSlice3Acap] = typecheck.LookupRuntimeFunc("panicSlice3Acap")
BoundsCheckFunc[ssa.BoundsSlice3AcapU] = typecheck.LookupRuntimeFunc("panicSlice3AcapU")
BoundsCheckFunc[ssa.BoundsSlice3B] = typecheck.LookupRuntimeFunc("panicSlice3B")
BoundsCheckFunc[ssa.BoundsSlice3BU] = typecheck.LookupRuntimeFunc("panicSlice3BU")
BoundsCheckFunc[ssa.BoundsSlice3C] = typecheck.LookupRuntimeFunc("panicSlice3C")
BoundsCheckFunc[ssa.BoundsSlice3CU] = typecheck.LookupRuntimeFunc("panicSlice3CU")
BoundsCheckFunc[ssa.BoundsConvert] = typecheck.LookupRuntimeFunc("panicSliceConvert")
}
if Arch.LinkArch.PtrSize == 4 {
ExtendCheckFunc[ssa.BoundsIndex] = typecheck.LookupRuntimeVar("panicExtendIndex")
ExtendCheckFunc[ssa.BoundsIndexU] = typecheck.LookupRuntimeVar("panicExtendIndexU")
ExtendCheckFunc[ssa.BoundsSliceAlen] = typecheck.LookupRuntimeVar("panicExtendSliceAlen")
ExtendCheckFunc[ssa.BoundsSliceAlenU] = typecheck.LookupRuntimeVar("panicExtendSliceAlenU")
ExtendCheckFunc[ssa.BoundsSliceAcap] = typecheck.LookupRuntimeVar("panicExtendSliceAcap")
ExtendCheckFunc[ssa.BoundsSliceAcapU] = typecheck.LookupRuntimeVar("panicExtendSliceAcapU")
ExtendCheckFunc[ssa.BoundsSliceB] = typecheck.LookupRuntimeVar("panicExtendSliceB")
ExtendCheckFunc[ssa.BoundsSliceBU] = typecheck.LookupRuntimeVar("panicExtendSliceBU")
ExtendCheckFunc[ssa.BoundsSlice3Alen] = typecheck.LookupRuntimeVar("panicExtendSlice3Alen")
ExtendCheckFunc[ssa.BoundsSlice3AlenU] = typecheck.LookupRuntimeVar("panicExtendSlice3AlenU")
ExtendCheckFunc[ssa.BoundsSlice3Acap] = typecheck.LookupRuntimeVar("panicExtendSlice3Acap")
ExtendCheckFunc[ssa.BoundsSlice3AcapU] = typecheck.LookupRuntimeVar("panicExtendSlice3AcapU")
ExtendCheckFunc[ssa.BoundsSlice3B] = typecheck.LookupRuntimeVar("panicExtendSlice3B")
ExtendCheckFunc[ssa.BoundsSlice3BU] = typecheck.LookupRuntimeVar("panicExtendSlice3BU")
ExtendCheckFunc[ssa.BoundsSlice3C] = typecheck.LookupRuntimeVar("panicExtendSlice3C")
ExtendCheckFunc[ssa.BoundsSlice3CU] = typecheck.LookupRuntimeVar("panicExtendSlice3CU")
}
// Wasm (all asm funcs with special ABIs)
ir.Syms.WasmMove = typecheck.LookupRuntimeVar("wasmMove")
ir.Syms.WasmZero = typecheck.LookupRuntimeVar("wasmZero")
ir.Syms.WasmDiv = typecheck.LookupRuntimeVar("wasmDiv")
ir.Syms.WasmTruncS = typecheck.LookupRuntimeVar("wasmTruncS")
ir.Syms.WasmTruncU = typecheck.LookupRuntimeVar("wasmTruncU")
ir.Syms.SigPanic = typecheck.LookupRuntimeFunc("sigpanic")
}
// AbiForBodylessFuncStackMap returns the ABI for a bodyless function's stack map.
// This is not necessarily the ABI used to call it.
// Currently (1.17 dev) such a stack map is always ABI0;
// any ABI wrapper that is present is nosplit, hence a precise
// stack map is not needed there (the parameters survive only long
// enough to call the wrapped assembly function).
// This always returns a freshly copied ABI.
func AbiForBodylessFuncStackMap(fn *ir.Func) *abi.ABIConfig {
return ssaConfig.ABI0.Copy() // No idea what races will result, be safe
}
// TODO (NLT 2021-04-15) This must be changed to a name that cannot match; it may be helpful to other register ABI work to keep the trigger-logic
const magicNameDotSuffix = ".MagicMethodNameForTestingRegisterABI"
const magicLastTypeName = "MagicLastTypeNameForTestingRegisterABI"
// abiForFunc implements ABI policy for a function, but does not return a copy of the ABI.
// Passing a nil function returns the default ABI based on experiment configuration.
func abiForFunc(fn *ir.Func, abi0, abi1 *abi.ABIConfig) *abi.ABIConfig {
if buildcfg.Experiment.RegabiArgs {
// Select the ABI based on the function's defining ABI.
if fn == nil {
return abi1
}
switch fn.ABI {
case obj.ABI0:
return abi0
case obj.ABIInternal:
// TODO(austin): Clean up the nomenclature here.
// It's not clear that "abi1" is ABIInternal.
return abi1
}
base.Fatalf("function %v has unknown ABI %v", fn, fn.ABI)
panic("not reachable")
}
a := abi0
if fn != nil {
name := ir.FuncName(fn)
magicName := strings.HasSuffix(name, magicNameDotSuffix)
if fn.Pragma&ir.RegisterParams != 0 { // TODO(register args) remove after register abi is working
if strings.Contains(name, ".") {
if !magicName {
base.ErrorfAt(fn.Pos(), "Calls to //go:registerparams method %s won't work, remove the pragma from the declaration.", name)
}
}
a = abi1
} else if magicName {
if base.FmtPos(fn.Pos()) == "<autogenerated>:1" {
// no way to put a pragma here, and it will error out in the real source code if they did not do it there.
a = abi1
} else {
base.ErrorfAt(fn.Pos(), "Methods with magic name %s (method %s) must also specify //go:registerparams", magicNameDotSuffix[1:], name)
}
}
if regAbiForFuncType(fn.Type().FuncType()) {
// fmt.Printf("Saw magic last type name for function %s\n", name)
a = abi1
}
}
return a
}
func regAbiForFuncType(ft *types.Func) bool {
np := ft.Params.NumFields()
return np > 0 && strings.Contains(ft.Params.FieldType(np-1).String(), magicLastTypeName)
}
// 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 *ir.CallExpr, i int) *types.Field {
t := n.X.Type()
if n.Op() == ir.OCALLMETH {
base.Fatalf("OCALLMETH missed by walkCall")
}
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 objw.Uint8(x, off, uint8(v))
}
off = objw.Uint8(x, off, uint8((v&127)|128))
if v < 1<<14 {
return objw.Uint8(x, off, uint8(v>>7))
}
off = objw.Uint8(x, off, uint8(((v>>7)&127)|128))
if v < 1<<21 {
return objw.Uint8(x, off, uint8(v>>14))
}
off = objw.Uint8(x, off, uint8(((v>>14)&127)|128))
if v < 1<<28 {
return objw.Uint8(x, off, uint8(v>>21))
}
off = objw.Uint8(x, off, uint8(((v>>21)&127)|128))
return objw.Uint8(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 := base.Ctxt.Lookup(s.curfn.LSym.Name + ".opendefer")
s.curfn.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.X.Type().ArgWidth() // TODO register args: but maybe use of abi0 will make this easy
if argsize > maxargsize {
maxargsize = argsize
}
}
off = dvarint(x, off, maxargsize)
off = dvarint(x, off, -s.deferBitsTemp.FrameOffset())
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.X.Type().ArgWidth())
off = dvarint(x, off, -r.closureNode.FrameOffset())
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))
argAdjust := 0 // presence of receiver offsets the parameter count.
if r.rcvrNode != nil {
off = dvarint(x, off, -okOffset(r.rcvrNode.FrameOffset()))
off = dvarint(x, off, s.config.PtrSize)
off = dvarint(x, off, 0) // This is okay because defer records use ABI0 (for now)
argAdjust++
}
// TODO(register args) assume abi0 for this?
ab := s.f.ABI0
pri := ab.ABIAnalyzeFuncType(r.n.X.Type().FuncType())
for j, arg := range r.argNodes {
f := getParam(r.n, j)
off = dvarint(x, off, -okOffset(arg.FrameOffset()))
off = dvarint(x, off, f.Type.Size())
off = dvarint(x, off, okOffset(pri.InParam(j+argAdjust).FrameOffset(pri)))
}
}
}
func okOffset(offset int64) int64 {
if offset == types.BOGUS_FUNARG_OFFSET {
panic(fmt.Errorf("Bogus offset %d", offset))
}
return offset
}
// buildssa builds an SSA function for fn.
// worker indicates which of the backend workers is doing the processing.
func buildssa(fn *ir.Func, worker int) *ssa.Func {
name := ir.FuncName(fn)
printssa := false
if ssaDump != "" { // match either a simple name e.g. "(*Reader).Reset", or a package.name e.g. "compress/gzip.(*Reader).Reset"
printssa = name == ssaDump || base.Ctxt.Pkgpath+"."+name == ssaDump
}
var astBuf *bytes.Buffer
if printssa {
astBuf = &bytes.Buffer{}
ir.FDumpList(astBuf, "buildssa-enter", fn.Enter)
ir.FDumpList(astBuf, "buildssa-body", fn.Body)
ir.FDumpList(astBuf, "buildssa-exit", fn.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.HasDefer()
if fn.Pragma&ir.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.Name = name
s.f.DebugTest = s.f.DebugHashMatch("GOSSAHASH")
s.f.PrintOrHtmlSSA = printssa
if fn.Pragma&ir.Nosplit != 0 {
s.f.NoSplit = true
}
s.f.ABI0 = ssaConfig.ABI0.Copy() // Make a copy to avoid racy map operations in type-register-width cache.
s.f.ABI1 = ssaConfig.ABI1.Copy()
s.f.ABIDefault = abiForFunc(nil, s.f.ABI0, s.f.ABI1)
s.f.ABISelf = abiForFunc(fn, s.f.ABI0, s.f.ABI1)
s.panics = map[funcLine]*ssa.Block{}
s.softFloat = s.config.SoftFloat
// Allocate starting block
s.f.Entry = s.f.NewBlock(ssa.BlockPlain)
s.f.Entry.Pos = fn.Pos()
if printssa {
ssaDF := ssaDumpFile
if ssaDir != "" {
ssaDF = filepath.Join(ssaDir, base.Ctxt.Pkgpath+"."+name+".html")
ssaD := filepath.Dir(ssaDF)
os.MkdirAll(ssaD, 0755)
}
s.f.HTMLWriter = ssa.NewHTMLWriter(ssaDF, 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 values
s.labels = map[string]*ssaLabel{}
s.fwdVars = map[ir.Node]*ssa.Value{}
s.startmem = s.entryNewValue0(ssa.OpInitMem, types.TypeMem)
s.hasOpenDefers = base.Flag.N == 0 && s.hasdefer && !s.curfn.OpenCodedDeferDisallowed()
switch {
case base.Debug.NoOpenDefer != 0:
s.hasOpenDefers = false
case s.hasOpenDefers && (base.Ctxt.Flag_shared || base.Ctxt.Flag_dynlink) && base.Ctxt.Arch.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 we don't track correctly.
s.hasOpenDefers = false
}
if s.hasOpenDefers && len(s.curfn.Exit) > 0 {
// Skip doing open defers if there is any extra exit code (likely
// race detection), since we will not generate that code in the
// case of the extra deferreturn/ret segment.
s.hasOpenDefers = false
}
if s.hasOpenDefers {
// Similarly, skip if there are any heap-allocated result
// parameters that need to be copied back to their stack slots.
for _, f := range s.curfn.Type().Results().FieldSlice() {
if !f.Nname.(*ir.Name).OnStack() {
s.hasOpenDefers = false
break
}
}
}
if s.hasOpenDefers &&
s.curfn.NumReturns*s.curfn.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[types.TUINTPTR]) // TODO: use generic pointer type (unsafe.Pointer?) instead
s.sb = s.entryNewValue0(ssa.OpSB, types.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 := typecheck.TempAt(src.NoXPos, s.curfn, types.Types[types.TUINT8])
deferBitsTemp.SetAddrtaken(true)
s.deferBitsTemp = deferBitsTemp
// For this value, AuxInt is initialized to zero by default
startDeferBits := s.entryNewValue0(ssa.OpConst8, types.Types[types.TUINT8])
s.vars[deferBitsVar] = startDeferBits
s.deferBitsAddr = s.addr(deferBitsTemp)
s.store(types.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)
}
var params *abi.ABIParamResultInfo
params = s.f.ABISelf.ABIAnalyze(fn.Type(), true)
// Generate addresses of local declarations
s.decladdrs = map[*ir.Name]*ssa.Value{}
for _, n := range fn.Dcl {
switch n.Class {
case ir.PPARAM:
// Be aware that blank and unnamed input parameters will not appear here, but do appear in the type
s.decladdrs[n] = s.entryNewValue2A(ssa.OpLocalAddr, types.NewPtr(n.Type()), n, s.sp, s.startmem)
case ir.PPARAMOUT:
s.decladdrs[n] = s.entryNewValue2A(ssa.OpLocalAddr, types.NewPtr(n.Type()), n, s.sp, s.startmem)
case ir.PAUTO:
// processed at each use, to prevent Addr coming
// before the decl.
default:
s.Fatalf("local variable with class %v unimplemented", n.Class)
}
}
s.f.OwnAux = ssa.OwnAuxCall(fn.LSym, params)
// Populate SSAable arguments.
for _, n := range fn.Dcl {
if n.Class == ir.PPARAM {
if 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.
} else { // address was taken AND/OR too large for SSA
paramAssignment := ssa.ParamAssignmentForArgName(s.f, n)
if len(paramAssignment.Registers) > 0 {
if TypeOK(n.Type()) { // SSA-able type, so address was taken -- receive value in OpArg, DO NOT bind to var, store immediately to memory.
v := s.newValue0A(ssa.OpArg, n.Type(), n)
s.store(n.Type(), s.decladdrs[n], v)
} else { // Too big for SSA.
// Brute force, and early, do a bunch of stores from registers
// TODO fix the nasty storeArgOrLoad recursion in ssa/expand_calls.go so this Just Works with store of a big Arg.
s.storeParameterRegsToStack(s.f.ABISelf, paramAssignment, n, s.decladdrs[n], false)
}
}
}
}
}
// Populate closure variables.
if !fn.ClosureCalled() {
clo := s.entryNewValue0(ssa.OpGetClosurePtr, s.f.Config.Types.BytePtr)
offset := int64(types.PtrSize) // PtrSize to skip past function entry PC field
for _, n := range fn.ClosureVars {
typ := n.Type()
if !n.Byval() {
typ = types.NewPtr(typ)
}
offset = types.Rnd(offset, typ.Alignment())
ptr := s.newValue1I(ssa.OpOffPtr, types.NewPtr(typ), offset, clo)
offset += typ.Size()
// If n is a small variable captured by value, promote
// it to PAUTO so it can be converted to SSA.
//
// Note: While we never capture a variable by value if
// the user took its address, we may have generated
// runtime calls that did (#43701). Since we don't
// convert Addrtaken variables to SSA anyway, no point
// in promoting them either.
if n.Byval() && !n.Addrtaken() && TypeOK(n.Type()) {
n.Class = ir.PAUTO
fn.Dcl = append(fn.Dcl, n)
s.assign(n, s.load(n.Type(), ptr), false, 0)
continue
}
if !n.Byval() {
ptr = s.load(typ, ptr)
}
s.setHeapaddr(fn.Pos(), n, ptr)
}
}
// Convert the AST-based IR to the SSA-based IR
s.stmtList(fn.Enter)
s.zeroResults()
s.paramsToHeap()
s.stmtList(fn.Body)
// fallthrough to exit
if s.curBlock != nil {
s.pushLine(fn.Endlineno)
s.exit()
s.popLine()
}
for _, b := range s.f.Blocks {
if b.Pos != src.NoXPos {
s.updateUnsetPredPos(b)
}
}
s.f.HTMLWriter.WritePhase("before insert phis", "before insert phis")
s.insertPhis()
// Main call to ssa package to compile function
ssa.Compile(s.f)
if s.hasOpenDefers {
s.emitOpenDeferInfo()
}
// Record incoming parameter spill information for morestack calls emitted in the assembler.
// This is done here, using all the parameters (used, partially used, and unused) because
// it mimics the behavior of the former ABI (everything stored) and because it's not 100%
// clear if naming conventions are respected in autogenerated code.
// TODO figure out exactly what's unused, don't spill it. Make liveness fine-grained, also.
// TODO non-amd64 architectures have link registers etc that may require adjustment here.
for _, p := range params.InParams() {
typs, offs := p.RegisterTypesAndOffsets()
for i, t := range typs {
o := offs[i] // offset within parameter
fo := p.FrameOffset(params) // offset of parameter in frame
reg := ssa.ObjRegForAbiReg(p.Registers[i], s.f.Config)
s.f.RegArgs = append(s.f.RegArgs, ssa.Spill{Reg: reg, Offset: fo + o, Type: t})
}
}
return s.f
}
func (s *state) storeParameterRegsToStack(abi *abi.ABIConfig, paramAssignment *abi.ABIParamAssignment, n *ir.Name, addr *ssa.Value, pointersOnly bool) {
typs, offs := paramAssignment.RegisterTypesAndOffsets()
for i, t := range typs {
if pointersOnly && !t.IsPtrShaped() {
continue
}
r := paramAssignment.Registers[i]
o := offs[i]
op, reg := ssa.ArgOpAndRegisterFor(r, abi)
aux := &ssa.AuxNameOffset{Name: n, Offset: o}
v := s.newValue0I(op, t, reg)
v.Aux = aux
p := s.newValue1I(ssa.OpOffPtr, types.NewPtr(t), o, addr)
s.store(t, p, v)
}
}
// zeroResults zeros the return values at the start of the function.
// We need to do this very early in the function. Defer might stop a
// panic and show the return values as they exist at the time of
// panic. For precise stacks, the garbage collector assumes results
// are always live, so we need to zero them before any allocations,
// even allocations to move params/results to the heap.
func (s *state) zeroResults() {
for _, f := range s.curfn.Type().Results().FieldSlice() {
n := f.Nname.(*ir.Name)
if !n.OnStack() {
// The local which points to the return value is the
// thing that needs zeroing. This is already handled
// by a Needzero annotation in plive.go:(*liveness).epilogue.
continue
}
// Zero the stack location containing f.
if typ := n.Type(); TypeOK(typ) {
s.assign(n, s.zeroVal(typ), false, 0)
} else {
s.vars[memVar] = s.newValue1A(ssa.OpVarDef, types.TypeMem, n, s.mem())
s.zero(n.Type(), s.decladdrs[n])
}
}
}
// paramsToHeap produces code to allocate memory for heap-escaped parameters
// and to copy non-result parameters' values from the stack.
func (s *state) paramsToHeap() {
do := func(params *types.Type) {
for _, f := range params.FieldSlice() {
if f.Nname == nil {
continue // anonymous or blank parameter
}
n := f.Nname.(*ir.Name)
if ir.IsBlank(n) || n.OnStack() {
continue
}
s.newHeapaddr(n)
if n.Class == ir.PPARAM {
s.move(n.Type(), s.expr(n.Heapaddr), s.decladdrs[n])
}
}
}
typ := s.curfn.Type()
do(typ.Recvs())
do(typ.Params())
do(typ.Results())
}
// newHeapaddr allocates heap memory for n and sets its heap address.
func (s *state) newHeapaddr(n *ir.Name) {
s.setHeapaddr(n.Pos(), n, s.newObject(n.Type()))
}
// setHeapaddr allocates a new PAUTO variable to store ptr (which must be non-nil)
// and then sets it as n's heap address.
func (s *state) setHeapaddr(pos src.XPos, n *ir.Name, ptr *ssa.Value) {
if !ptr.Type.IsPtr() || !types.Identical(n.Type(), ptr.Type.Elem()) {
base.FatalfAt(n.Pos(), "setHeapaddr %L with type %v", n, ptr.Type)
}
// Declare variable to hold address.
addr := ir.NewNameAt(pos, &types.Sym{Name: "&" + n.Sym().Name, Pkg: types.LocalPkg})
addr.SetType(types.NewPtr(n.Type()))
addr.Class = ir.PAUTO
addr.SetUsed(true)
addr.Curfn = s.curfn
s.curfn.Dcl = append(s.curfn.Dcl, addr)
types.CalcSize(addr.Type())
if n.Class == ir.PPARAMOUT {
addr.SetIsOutputParamHeapAddr(true)
}
n.Heapaddr = addr
s.assign(addr, ptr, false, 0)
}
// newObject returns an SSA value denoting new(typ).
func (s *state) newObject(typ *types.Type) *ssa.Value {
if typ.Size() == 0 {
return s.newValue1A(ssa.OpAddr, types.NewPtr(typ), ir.Syms.Zerobase, s.sb)
}
return s.rtcall(ir.Syms.Newobject, true, []*types.Type{types.NewPtr(typ)}, s.reflectType(typ))[0]
}
// reflectType returns an SSA value representing a pointer to typ's
// reflection type descriptor.
func (s *state) reflectType(typ *types.Type) *ssa.Value {
lsym := reflectdata.TypeLinksym(typ)
return s.entryNewValue1A(ssa.OpAddr, types.NewPtr(types.Types[types.TUINT8]), lsym, s.sb)
}
func dumpSourcesColumn(writer *ssa.HTMLWriter, fn *ir.Func) {
// Read sources of target function fn.
fname := base.Ctxt.PosTable.Pos(fn.Pos()).Filename()
targetFn, err := readFuncLines(fname, fn.Pos().Line(), fn.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 {
elno := fi.Endlineno
fname := base.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 node representing the call of the defer
n *ir.CallExpr
// 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 *ir.Name
// 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 *ir.Name
// 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 []*ir.Name
}
type state struct {
// configuration (arch) information
config *ssa.Config
// function we're building
f *ssa.Func
// Node for function
curfn *ir.Func
// labels in f
labels map[string]*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[ir.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[ir.Node]*ssa.Value
// all defined variables at the end of each block. Indexed by block ID.
defvars []map[ir.Node]*ssa.Value
// addresses of PPARAM and PPARAMOUT variables on the stack.
decladdrs map[*ir.Name]*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 *ir.Name
// 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
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
prevCall *ssa.Value // the previous call; use this to tie results to the call op.
}
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() }
func ssaMarker(name string) *ir.Name {
return typecheck.NewName(&types.Sym{Name: name})
}
var (
// marker node for the memory variable
memVar = ssaMarker("mem")
// marker nodes for temporary variables
ptrVar = ssaMarker("ptr")
lenVar = ssaMarker("len")
newlenVar = ssaMarker("newlen")
capVar = ssaMarker("cap")
typVar = ssaMarker("typ")
okVar = ssaMarker("ok")
deferBitsVar = ssaMarker("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[ir.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 base.Flag.K != 0 {
base.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 ssa.Aux) *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 ssa.Aux, 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 ssa.Aux, 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)
}
// newValue2A adds a new value with two arguments and an aux value to the current block.
func (s *state) newValue2A(op ssa.Op, t *types.Type, aux ssa.Aux, arg0, arg1 *ssa.Value) *ssa.Value {
return s.curBlock.NewValue2A(s.peekPos(), op, t, aux, 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 ssa.Aux, 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 ssa.Aux, 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 ssa.Aux, 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 ssa.Aux) *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 ssa.Aux, 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 ssa.Aux, 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[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)
}
type instrumentKind uint8
const (
instrumentRead = iota
instrumentWrite
instrumentMove
)
func (s *state) instrument(t *types.Type, addr *ssa.Value, kind instrumentKind) {
s.instrument2(t, addr, nil, kind)
}
// instrumentFields instruments a read/write operation on addr.
// If it is instrumenting for MSAN and t is a struct type, it instruments
// operation for each field, instead of for the whole struct.
func (s *state) instrumentFields(t *types.Type, addr *ssa.Value, kind instrumentKind) {
if !base.Flag.MSan || !t.IsStruct() {
s.instrument(t, addr, kind)
return
}
for _, f := range t.Fields().Slice() {
if f.Sym.IsBlank() {
continue
}
offptr := s.newValue1I(ssa.OpOffPtr, types.NewPtr(f.Type), abi.FieldOffsetOf(f), addr)
s.instrumentFields(f.Type, offptr, kind)
}
}
func (s *state) instrumentMove(t *types.Type, dst, src *ssa.Value) {
if base.Flag.MSan {
s.instrument2(t, dst, src, instrumentMove)
} else {
s.instrument(t, src, instrumentRead)
s.instrument(t, dst, instrumentWrite)
}
}
func (s *state) instrument2(t *types.Type, addr, addr2 *ssa.Value, kind instrumentKind) {
if !s.curfn.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 addr2 != nil && kind != instrumentMove {
panic("instrument2: non-nil addr2 for non-move instrumentation")
}
if base.Flag.MSan {
switch kind {
case instrumentRead:
fn = ir.Syms.Msanread
case instrumentWrite:
fn = ir.Syms.Msanwrite
case instrumentMove:
fn = ir.Syms.Msanmove
default:
panic("unreachable")
}
needWidth = true
} else if base.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.
switch kind {
case instrumentRead:
fn = ir.Syms.Racereadrange
case instrumentWrite:
fn = ir.Syms.Racewriterange
default:
panic("unreachable")
}
needWidth = true
} else if base.Flag.Race {
// for non-composite objects we can write just the start
// address, as any write must write the first byte.
switch kind {
case instrumentRead:
fn = ir.Syms.Raceread
case instrumentWrite:
fn = ir.Syms.Racewrite
default:
panic("unreachable")
}
} else {
panic("unreachable")
}
args := []*ssa.Value{addr}
if addr2 != nil {
args = append(args, addr2)
}
if needWidth {
args = append(args, s.constInt(types.Types[types.TUINTPTR], w))
}
s.rtcall(fn, true, nil, args...)
}
func (s *state) load(t *types.Type, src *ssa.Value) *ssa.Value {
s.instrumentFields(t, src, instrumentRead)
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, instrumentWrite)
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.instrumentMove(t, dst, src)
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 ir.Nodes) {
for _, n := range l {
s.stmt(n)
}
}
// stmt converts the statement n to SSA and adds it to s.
func (s *state) stmt(n ir.Node) {
if !(n.Op() == ir.OVARKILL || n.Op() == ir.OVARLIVE || n.Op() == ir.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() != ir.OLABEL {
return
}
s.stmtList(n.Init())
switch n.Op() {
case ir.OBLOCK:
n := n.(*ir.BlockStmt)
s.stmtList(n.List)
// No-ops
case ir.ODCLCONST, ir.ODCLTYPE, ir.OFALL:
// Expression statements
case ir.OCALLFUNC:
n := n.(*ir.CallExpr)
if ir.IsIntrinsicCall(n) {
s.intrinsicCall(n)
return
}
fallthrough
case ir.OCALLINTER:
n := n.(*ir.CallExpr)
s.callResult(n, callNormal)
if n.Op() == ir.OCALLFUNC && n.X.Op() == ir.ONAME && n.X.(*ir.Name).Class == ir.PFUNC {
if fn := n.X.Sym().Name; base.Flag.CompilingRuntime && fn == "throw" ||
n.X.Sym().Pkg == ir.Pkgs.Runtime && (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 ir.ODEFER:
n := n.(*ir.GoDeferStmt)
if base.Debug.Defer > 0 {
var defertype string
if s.hasOpenDefers {
defertype = "open-coded"
} else if n.Esc() == ir.EscNever {
defertype = "stack-allocated"
} else {
defertype = "heap-allocated"
}
base.WarnfAt(n.Pos(), "%s defer", defertype)
}
if s.hasOpenDefers {
s.openDeferRecord(n.Call.(*ir.CallExpr))
} else {
d := callDefer
if n.Esc() == ir.EscNever {
d = callDeferStack
}
s.callResult(n.Call.(*ir.CallExpr), d)
}
case ir.OGO:
n := n.(*ir.GoDeferStmt)
s.callResult(n.Call.(*ir.CallExpr), callGo)
case ir.OAS2DOTTYPE:
n := n.(*ir.AssignListStmt)
res, resok := s.dottype(n.Rhs[0].(*ir.TypeAssertExpr), true)
deref := false
if !TypeOK(n.Rhs[0].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.Lhs[0], res, deref, 0)
s.assign(n.Lhs[1], resok, false, 0)
return
case ir.OAS2FUNC:
// We come here only when it is an intrinsic call returning two values.
n := n.(*ir.AssignListStmt)
call := n.Rhs[0].(*ir.CallExpr)
if !ir.IsIntrinsicCall(call) {
s.Fatalf("non-intrinsic AS2FUNC not expanded %v", call)
}
v := s.intrinsicCall(call)
v1 := s.newValue1(ssa.OpSelect0, n.Lhs[0].Type(), v)
v2 := s.newValue1(ssa.OpSelect1, n.Lhs[1].Type(), v)
s.assign(n.Lhs[0], v1, false, 0)
s.assign(n.Lhs[1], v2, false, 0)
return
case ir.ODCL:
n := n.(*ir.Decl)
if v := n.X; v.Esc() == ir.EscHeap {
s.newHeapaddr(v)
}
case ir.OLABEL:
n := n.(*ir.LabelStmt)
sym := n.Label
lab := s.label(sym)
// 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 ir.OGOTO:
n := n.(*ir.BranchStmt)
sym := n.Label
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 ir.OAS:
n := n.(*ir.AssignStmt)
if n.X == n.Y && n.X.Op() == ir.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.Y
if rhs != nil {
switch rhs.Op() {
case ir.OSTRUCTLIT, ir.OARRAYLIT, ir.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 !ir.IsZero(rhs) {
s.Fatalf("literal with nonzero value in SSA: %v", rhs)
}
rhs = nil
case ir.OAPPEND:
rhs := rhs.(*ir.CallExpr)
// 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 !ir.SameSafeExpr(n.X, rhs.Args[0]) || base.Flag.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.X) {
if base.Debug.Append > 0 { // replicating old diagnostic message
base.WarnfAt(n.Pos(), "append: len-only update (in local slice)")
}
break
}
if base.Debug.Append > 0 {
base.WarnfAt(n.Pos(), "append: len-only update")
}
s.append(rhs, true)
return
}
}
if ir.IsBlank(n.X) {
// _ = rhs
// Just evaluate rhs for side-effects.
if rhs != nil {
s.expr(rhs)
}
return
}
var t *types.Type
if n.Y != nil {
t = n.Y.Type()
} else {
t = n.X.Type()
}
var r *ssa.Value
deref := !TypeOK(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() == ir.OSLICE || rhs.Op() == ir.OSLICE3 || rhs.Op() == ir.OSLICESTR) && ir.SameSafeExpr(rhs.(*ir.SliceExpr).X, n.X) {
// We're assigning a slicing operation back to its source.
// Don't write back fields we aren't changing. See issue #14855.
rhs := rhs.(*ir.SliceExpr)
i, j, k := rhs.Low, rhs.High, rhs.Max
if i != nil && (i.Op() == ir.OLITERAL && i.Val().Kind() == constant.Int && ir.Int64Val(i) == 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.X, r, deref, skip)
case ir.OIF:
n := n.(*ir.IfStmt)
if ir.IsConst(n.Cond, constant.Bool) {
s.stmtList(n.Cond.Init())
if ir.BoolVal(n.Cond) {
s.stmtList(n.Body)
} else {
s.stmtList(n.Else)
}
break
}
bEnd := s.f.NewBlock(ssa.BlockPlain)
var likely int8
if n.Likely {
likely = 1
}
var bThen *ssa.Block
if len(n.Body) != 0 {
bThen = s.f.NewBlock(ssa.BlockPlain)
} else {
bThen = bEnd
}
var bElse *ssa.Block
if len(n.Else) != 0 {
bElse = s.f.NewBlock(ssa.BlockPlain)
} else {
bElse = bEnd
}
s.condBranch(n.Cond, bThen, bElse, likely)
if len(n.Body) != 0 {
s.startBlock(bThen)
s.stmtList(n.Body)
if b := s.endBlock(); b != nil {
b.AddEdgeTo(bEnd)
}
}
if len(n.Else) != 0 {
s.startBlock(bElse)
s.stmtList(n.Else)
if b := s.endBlock(); b != nil {
b.AddEdgeTo(bEnd)
}
}
s.startBlock(bEnd)
case ir.ORETURN:
n := n.(*ir.ReturnStmt)
s.stmtList(n.Results)
b := s.exit()
b.Pos = s.lastPos.WithIsStmt()
case ir.OTAILCALL:
n := n.(*ir.TailCallStmt)
b := s.exit()
b.Kind = ssa.BlockRetJmp // override BlockRet
b.Aux = callTargetLSym(n.Target)
case ir.OCONTINUE, ir.OBREAK:
n := n.(*ir.BranchStmt)
var to *ssa.Block
if n.Label == nil {
// plain break/continue
switch n.Op() {
case ir.OCONTINUE:
to = s.continueTo
case ir.OBREAK:
to = s.breakTo
}
} else {
// labeled break/continue; look up the target
sym := n.Label
lab := s.label(sym)
switch n.Op() {
case ir.OCONTINUE:
to = lab.continueTarget
case ir.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 ir.OFOR, ir.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:
n := n.(*ir.ForStmt)
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() == ir.OFOR {
b.AddEdgeTo(bCond)
// generate code to test condition
s.startBlock(bCond)
if n.Cond != nil {
s.condBranch(n.Cond, 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
var lab *ssaLabel
if sym := n.Label; sym != nil {
// labeled for loop
lab = s.label(sym)
lab.continueTarget = bIncr
lab.breakTarget = bEnd
}
// generate body
s.startBlock(bBody)
s.stmtList(n.Body)
// 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.Post != nil {
s.stmt(n.Post)
}
if n.Op() == ir.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 b.Pos == src.NoXPos {
b.Pos = bCond.Pos
}
}
} else {
// bCond is unused in OFORUNTIL, so repurpose it.
bLateIncr := bCond
// test condition
s.condBranch(n.Cond, bLateIncr, bEnd, 1)
// generate late increment
s.startBlock(bLateIncr)
s.stmtList(n.Late)
s.endBlock().AddEdgeTo(bBody)
}
s.startBlock(bEnd)
case ir.OSWITCH, ir.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
var sym *types.Sym
var body ir.Nodes
if n.Op() == ir.OSWITCH {
n := n.(*ir.SwitchStmt)
sym = n.Label
body = n.Compiled
} else {
n := n.(*ir.SelectStmt)
sym = n.Label
body = n.Compiled
}
var lab *ssaLabel
if sym != nil {
// labeled
lab = s.label(sym)
lab.breakTarget = bEnd
}
// generate body code
s.stmtList(body)
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 ir.OVARDEF:
n := n.(*ir.UnaryExpr)
if !s.canSSA(n.X) {
s.vars[memVar] = s.newValue1Apos(ssa.OpVarDef, types.TypeMem, n.X.(*ir.Name), s.mem(), false)
}
case ir.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.
n := n.(*ir.UnaryExpr)
if !s.canSSA(n.X) {
s.vars[memVar] = s.newValue1Apos(ssa.OpVarKill, types.TypeMem, n.X.(*ir.Name), s.mem(), false)
}
case ir.OVARLIVE:
// Insert a varlive op to record that a variable is still live.
n := n.(*ir.UnaryExpr)
v := n.X.(*ir.Name)
if !v.Addrtaken() {
s.Fatalf("VARLIVE variable %v must have Addrtaken set", v)
}
switch v.Class {
case ir.PAUTO, ir.PPARAM, ir.PPARAMOUT:
default:
s.Fatalf("VARLIVE variable %v must be Auto or Arg", v)
}
s.vars[memVar] = s.newValue1A(ssa.OpVarLive, types.TypeMem, v, s.mem())
case ir.OCHECKNIL:
n := n.(*ir.UnaryExpr)
p := s.expr(n.X)
s.nilCheck(p)
case ir.OINLMARK:
n := n.(*ir.InlineMarkStmt)
s.newValue1I(ssa.OpInlMark, types.TypeVoid, n.Index, 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(ir.Syms.Deferreturn, true, nil)
}
}
var b *ssa.Block
var m *ssa.Value
// Do actual return.
// These currently turn into self-copies (in many cases).
resultFields := s.curfn.Type().Results().FieldSlice()
results := make([]*ssa.Value, len(resultFields)+1, len(resultFields)+1)
m = s.newValue0(ssa.OpMakeResult, s.f.OwnAux.LateExpansionResultType())
// Store SSAable and heap-escaped PPARAMOUT variables back to stack locations.
for i, f := range resultFields {
n := f.Nname.(*ir.Name)
if s.canSSA(n) { // result is in some SSA variable
if !n.IsOutputParamInRegisters() {
// We are about to store to the result slot.
s.vars[memVar] = s.newValue1A(ssa.OpVarDef, types.TypeMem, n, s.mem())
}
results[i] = s.variable(n, n.Type())
} else if !n.OnStack() { // result is actually heap allocated
// We are about to copy the in-heap result to the result slot.
s.vars[memVar] = s.newValue1A(ssa.OpVarDef, types.TypeMem, n, s.mem())
ha := s.expr(n.Heapaddr)
s.instrumentFields(n.Type(), ha, instrumentRead)
results[i] = s.newValue2(ssa.OpDereference, n.Type(), ha, s.mem())
} else { // result is not SSA-able; not escaped, so not on heap, but too large for SSA.
// Before register ABI this ought to be a self-move, home=dest,
// With register ABI, it's still a self-move if parameter is on stack (i.e., too big or overflowed)
// No VarDef, as the result slot is already holding live value.
results[i] = s.newValue2(ssa.OpDereference, n.Type(), s.addr(n), s.mem())
}
}
// Run exit code. Today, this is just racefuncexit, in -race mode.
// TODO(register args) this seems risky here with a register-ABI, but not clear it is right to do it earlier either.
// Spills in register allocation might just fix it.
s.stmtList(s.curfn.Exit)
results[len(results)-1] = s.mem()
m.AddArgs(results...)
b = s.endBlock()
b.Kind = ssa.BlockRet
b.SetControl(m)
if s.hasdefer && s.hasOpenDefers {
s.lastDeferFinalBlock = b
}
return b
}
type opAndType struct {
op ir.Op
etype types.Kind
}
var opToSSA = map[opAndType]ssa.Op{
opAndType{ir.OADD, types.TINT8}: ssa.OpAdd8,
opAndType{ir.OADD, types.TUINT8}: ssa.OpAdd8,
opAndType{ir.OADD, types.TINT16}: ssa.OpAdd16,
opAndType{ir.OADD, types.TUINT16}: ssa.OpAdd16,
opAndType{ir.OADD, types.TINT32}: ssa.OpAdd32,
opAndType{ir.OADD, types.TUINT32}: ssa.OpAdd32,
opAndType{ir.OADD, types.TINT64}: ssa.OpAdd64,
opAndType{ir.OADD, types.TUINT64}: ssa.OpAdd64,
opAndType{ir.OADD, types.TFLOAT32}: ssa.OpAdd32F,
opAndType{ir.OADD, types.TFLOAT64}: ssa.OpAdd64F,
opAndType{ir.OSUB, types.TINT8}: ssa.OpSub8,
opAndType{ir.OSUB, types.TUINT8}: ssa.OpSub8,
opAndType{ir.OSUB, types.TINT16}: ssa.OpSub16,
opAndType{ir.OSUB, types.TUINT16}: ssa.OpSub16,
opAndType{ir.OSUB, types.TINT32}: ssa.OpSub32,
opAndType{ir.OSUB, types.TUINT32}: ssa.OpSub32,
opAndType{ir.OSUB, types.TINT64}: ssa.OpSub64,
opAndType{ir.OSUB, types.TUINT64}: ssa.OpSub64,
opAndType{ir.OSUB, types.TFLOAT32}: ssa.OpSub32F,
opAndType{ir.OSUB, types.TFLOAT64}: ssa.OpSub64F,
opAndType{ir.ONOT, types.TBOOL}: ssa.OpNot,
opAndType{ir.ONEG, types.TINT8}: ssa.OpNeg8,
opAndType{ir.ONEG, types.TUINT8}: ssa.OpNeg8,
opAndType{ir.ONEG, types.TINT16}: ssa.OpNeg16,
opAndType{ir.ONEG, types.TUINT16}: ssa.OpNeg16,
opAndType{ir.ONEG, types.TINT32}: ssa.OpNeg32,
opAndType{ir.ONEG, types.TUINT32}: ssa.OpNeg32,
opAndType{ir.ONEG, types.TINT64}: ssa.OpNeg64,
opAndType{ir.ONEG, types.TUINT64}: ssa.OpNeg64,
opAndType{ir.ONEG, types.TFLOAT32}: ssa.OpNeg32F,
opAndType{ir.ONEG, types.TFLOAT64}: ssa.OpNeg64F,
opAndType{ir.OBITNOT, types.TINT8}: ssa.OpCom8,
opAndType{ir.OBITNOT, types.TUINT8}: ssa.OpCom8,
opAndType{ir.OBITNOT, types.TINT16}: ssa.OpCom16,
opAndType{ir.OBITNOT, types.TUINT16}: ssa.OpCom16,
opAndType{ir.OBITNOT, types.TINT32}: ssa.OpCom32,
opAndType{ir.OBITNOT, types.TUINT32}: ssa.OpCom32,
opAndType{ir.OBITNOT, types.TINT64}: ssa.OpCom64,
opAndType{ir.OBITNOT, types.TUINT64}: ssa.OpCom64,
opAndType{ir.OIMAG, types.TCOMPLEX64}: ssa.OpComplexImag,
opAndType{ir.OIMAG, types.TCOMPLEX128}: ssa.OpComplexImag,
opAndType{ir.OREAL, types.TCOMPLEX64}: ssa.OpComplexReal,
opAndType{ir.OREAL, types.TCOMPLEX128}: ssa.OpComplexReal,
opAndType{ir.OMUL, types.TINT8}: ssa.OpMul8,
opAndType{ir.OMUL, types.TUINT8}: ssa.OpMul8,
opAndType{ir.OMUL, types.TINT16}: ssa.OpMul16,
opAndType{ir.OMUL, types.TUINT16}: ssa.OpMul16,
opAndType{ir.OMUL, types.TINT32}: ssa.OpMul32,
opAndType{ir.OMUL, types.TUINT32}: ssa.OpMul32,
opAndType{ir.OMUL, types.TINT64}: ssa.OpMul64,
opAndType{ir.OMUL, types.TUINT64}: ssa.OpMul64,
opAndType{ir.OMUL, types.TFLOAT32}: ssa.OpMul32F,
opAndType{ir.OMUL, types.TFLOAT64}: ssa.OpMul64F,
opAndType{ir.ODIV, types.TFLOAT32}: ssa.OpDiv32F,
opAndType{ir.ODIV, types.TFLOAT64}: ssa.OpDiv64F,
opAndType{ir.ODIV, types.TINT8}: ssa.OpDiv8,
opAndType{ir.ODIV, types.TUINT8}: ssa.OpDiv8u,
opAndType{ir.ODIV, types.TINT16}: ssa.OpDiv16,
opAndType{ir.ODIV, types.TUINT16}: ssa.OpDiv16u,
opAndType{ir.ODIV, types.TINT32}: ssa.OpDiv32,
opAndType{ir.ODIV, types.TUINT32}: ssa.OpDiv32u,
opAndType{ir.ODIV, types.TINT64}: ssa.OpDiv64,
opAndType{ir.ODIV, types.TUINT64}: ssa.OpDiv64u,
opAndType{ir.OMOD, types.TINT8}: ssa.OpMod8,
opAndType{ir.OMOD, types.TUINT8}: ssa.OpMod8u,
opAndType{ir.OMOD, types.TINT16}: ssa.OpMod16,
opAndType{ir.OMOD, types.TUINT16}: ssa.OpMod16u,
opAndType{ir.OMOD, types.TINT32}: ssa.OpMod32,
opAndType{ir.OMOD, types.TUINT32}: ssa.OpMod32u,
opAndType{ir.OMOD, types.TINT64}: ssa.OpMod64,
opAndType{ir.OMOD, types.TUINT64}: ssa.OpMod64u,
opAndType{ir.OAND, types.TINT8}: ssa.OpAnd8,
opAndType{ir.OAND, types.TUINT8}: ssa.OpAnd8,
opAndType{ir.OAND, types.TINT16}: ssa.OpAnd16,
opAndType{ir.OAND, types.TUINT16}: ssa.OpAnd16,
opAndType{ir.OAND, types.TINT32}: ssa.OpAnd32,
opAndType{ir.OAND, types.TUINT32}: ssa.OpAnd32,
opAndType{ir.OAND, types.TINT64}: ssa.OpAnd64,
opAndType{ir.OAND, types.TUINT64}: ssa.OpAnd64,
opAndType{ir.OOR, types.TINT8}: ssa.OpOr8,
opAndType{ir.OOR, types.TUINT8}: ssa.OpOr8,
opAndType{ir.OOR, types.TINT16}: ssa.OpOr16,
opAndType{ir.OOR, types.TUINT16}: ssa.OpOr16,
opAndType{ir.OOR, types.TINT32}: ssa.OpOr32,
opAndType{ir.OOR, types.TUINT32}: ssa.OpOr32,
opAndType{ir.OOR, types.TINT64}: ssa.OpOr64,
opAndType{ir.OOR, types.TUINT64}: ssa.OpOr64,
opAndType{ir.OXOR, types.TINT8}: ssa.OpXor8,
opAndType{ir.OXOR, types.TUINT8}: ssa.OpXor8,
opAndType{ir.OXOR, types.TINT16}: ssa.OpXor16,
opAndType{ir.OXOR, types.TUINT16}: ssa.OpXor16,
opAndType{ir.OXOR, types.TINT32}: ssa.OpXor32,
opAndType{ir.OXOR, types.TUINT32}: ssa.OpXor32,
opAndType{ir.OXOR, types.TINT64}: ssa.OpXor64,
opAndType{ir.OXOR, types.TUINT64}: ssa.OpXor64,
opAndType{ir.OEQ, types.TBOOL}: ssa.OpEqB,
opAndType{ir.OEQ, types.TINT8}: ssa.OpEq8,
opAndType{ir.OEQ, types.TUINT8}: ssa.OpEq8,
opAndType{ir.OEQ, types.TINT16}: ssa.OpEq16,
opAndType{ir.OEQ, types.TUINT16}: ssa.OpEq16,
opAndType{ir.OEQ, types.TINT32}: ssa.OpEq32,
opAndType{ir.OEQ, types.TUINT32}: ssa.OpEq32,
opAndType{ir.OEQ, types.TINT64}: ssa.OpEq64,
opAndType{ir.OEQ, types.TUINT64}: ssa.OpEq64,
opAndType{ir.OEQ, types.TINTER}: ssa.OpEqInter,
opAndType{ir.OEQ, types.TSLICE}: ssa.OpEqSlice,
opAndType{ir.OEQ, types.TFUNC}: ssa.OpEqPtr,
opAndType{ir.OEQ, types.TMAP}: ssa.OpEqPtr,
opAndType{ir.OEQ, types.TCHAN}: ssa.OpEqPtr,
opAndType{ir.OEQ, types.TPTR}: ssa.OpEqPtr,
opAndType{ir.OEQ, types.TUINTPTR}: ssa.OpEqPtr,
opAndType{ir.OEQ, types.TUNSAFEPTR}: ssa.OpEqPtr,
opAndType{ir.OEQ, types.TFLOAT64}: ssa.OpEq64F,
opAndType{ir.OEQ, types.TFLOAT32}: ssa.OpEq32F,
opAndType{ir.ONE, types.TBOOL}: ssa.OpNeqB,
opAndType{ir.ONE, types.TINT8}: ssa.OpNeq8,
opAndType{ir.ONE, types.TUINT8}: ssa.OpNeq8,
opAndType{ir.ONE, types.TINT16}: ssa.OpNeq16,
opAndType{ir.ONE, types.TUINT16}: ssa.OpNeq16,
opAndType{ir.ONE, types.TINT32}: ssa.OpNeq32,
opAndType{ir.ONE, types.TUINT32}: ssa.OpNeq32,
opAndType{ir.ONE, types.TINT64}: ssa.OpNeq64,
opAndType{ir.ONE, types.TUINT64}: ssa.OpNeq64,
opAndType{ir.ONE, types.TINTER}: ssa.OpNeqInter,
opAndType{ir.ONE, types.TSLICE}: ssa.OpNeqSlice,
opAndType{ir.ONE, types.TFUNC}: ssa.OpNeqPtr,
opAndType{ir.ONE, types.TMAP}: ssa.OpNeqPtr,
opAndType{ir.ONE, types.TCHAN}: ssa.OpNeqPtr,
opAndType{ir.ONE, types.TPTR}: ssa.OpNeqPtr,
opAndType{ir.ONE, types.TUINTPTR}: ssa.OpNeqPtr,
opAndType{ir.ONE, types.TUNSAFEPTR}: ssa.OpNeqPtr,
opAndType{ir.ONE, types.TFLOAT64}: ssa.OpNeq64F,
opAndType{ir.ONE, types.TFLOAT32}: ssa.OpNeq32F,
opAndType{ir.OLT, types.TINT8}: ssa.OpLess8,
opAndType{ir.OLT, types.TUINT8}: ssa.OpLess8U,
opAndType{ir.OLT, types.TINT16}: ssa.OpLess16,
opAndType{ir.OLT, types.TUINT16}: ssa.OpLess16U,
opAndType{ir.OLT, types.TINT32}: ssa.OpLess32,
opAndType{ir.OLT, types.TUINT32}: ssa.OpLess32U,
opAndType{ir.OLT, types.TINT64}: ssa.OpLess64,
opAndType{ir.OLT, types.TUINT64}: ssa.OpLess64U,
opAndType{ir.OLT, types.TFLOAT64}: ssa.OpLess64F,
opAndType{ir.OLT, types.TFLOAT32}: ssa.OpLess32F,
opAndType{ir.OLE, types.TINT8}: ssa.OpLeq8,
opAndType{ir.OLE, types.TUINT8}: ssa.OpLeq8U,
opAndType{ir.OLE, types.TINT16}: ssa.OpLeq16,
opAndType{ir.OLE, types.TUINT16}: ssa.OpLeq16U,
opAndType{ir.OLE, types.TINT32}: ssa.OpLeq32,
opAndType{ir.OLE, types.TUINT32}: ssa.OpLeq32U,
opAndType{ir.OLE, types.TINT64}: ssa.OpLeq64,
opAndType{ir.OLE, types.TUINT64}: ssa.OpLeq64U,
opAndType{ir.OLE, types.TFLOAT64}: ssa.OpLeq64F,
opAndType{ir.OLE, types.TFLOAT32}: ssa.OpLeq32F,
}
func (s *state) concreteEtype(t *types.Type) types.Kind {
e := t.Kind()
switch e {
default:
return e
case types.TINT:
if s.config.PtrSize == 8 {
return types.TINT64
}
return types.TINT32
case types.TUINT:
if s.config.PtrSize == 8 {
return types.TUINT64
}
return types.TUINT32
case types.TUINTPTR:
if s.config.PtrSize == 8 {
return types.TUINT64
}
return types.TUINT32
}
}
func (s *state) ssaOp(op ir.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
}
type opAndTwoTypes struct {
op ir.Op
etype1 types.Kind
etype2 types.Kind
}
type twoTypes struct {
etype1 types.Kind
etype2 types.Kind
}
type twoOpsAndType struct {
op1 ssa.Op
op2 ssa.Op
intermediateType types.Kind
}
var fpConvOpToSSA = map[twoTypes]twoOpsAndType{
twoTypes{types.TINT8, types.TFLOAT32}: twoOpsAndType{ssa.OpSignExt8to32, ssa.OpCvt32to32F, types.TINT32},
twoTypes{types.TINT16, types.TFLOAT32}: twoOpsAndType{ssa.OpSignExt16to32, ssa.OpCvt32to32F, types.TINT32},
twoTypes{types.TINT32, types.TFLOAT32}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt32to32F, types.TINT32},
twoTypes{types.TINT64, types.TFLOAT32}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt64to32F, types.TINT64},
twoTypes{types.TINT8, types.TFLOAT64}: twoOpsAndType{ssa.OpSignExt8to32, ssa.OpCvt32to64F, types.TINT32},
twoTypes{types.TINT16, types.TFLOAT64}: twoOpsAndType{ssa.OpSignExt16to32, ssa.OpCvt32to64F, types.TINT32},
twoTypes{types.TINT32, types.TFLOAT64}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt32to64F, types.TINT32},
twoTypes{types.TINT64, types.TFLOAT64}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt64to64F, types.TINT64},
twoTypes{types.TFLOAT32, types.TINT8}: twoOpsAndType{ssa.OpCvt32Fto32, ssa.OpTrunc32to8, types.TINT32},
twoTypes{types.TFLOAT32, types.TINT16}: twoOpsAndType{ssa.OpCvt32Fto32, ssa.OpTrunc32to16, types.TINT32},
twoTypes{types.TFLOAT32, types.TINT32}: twoOpsAndType{ssa.OpCvt32Fto32, ssa.OpCopy, types.TINT32},
twoTypes{types.TFLOAT32, types.TINT64}: twoOpsAndType{ssa.OpCvt32Fto64, ssa.OpCopy, types.TINT64},
twoTypes{types.TFLOAT64, types.TINT8}: twoOpsAndType{ssa.OpCvt64Fto32, ssa.OpTrunc32to8, types.TINT32},
twoTypes{types.TFLOAT64, types.TINT16}: twoOpsAndType{ssa.OpCvt64Fto32, ssa.OpTrunc32to16, types.TINT32},
twoTypes{types.TFLOAT64, types.TINT32}: twoOpsAndType{ssa.OpCvt64Fto32, ssa.OpCopy, types.TINT32},
twoTypes{types.TFLOAT64, types.TINT64}: twoOpsAndType{ssa.OpCvt64Fto64, ssa.OpCopy, types.TINT64},
// unsigned
twoTypes{types.TUINT8, types.TFLOAT32}: twoOpsAndType{ssa.OpZeroExt8to32, ssa.OpCvt32to32F, types.TINT32},
twoTypes{types.TUINT16, types.TFLOAT32}: twoOpsAndType{ssa.OpZeroExt16to32, ssa.OpCvt32to32F, types.TINT32},
twoTypes{types.TUINT32, types.TFLOAT32}: twoOpsAndType{ssa.OpZeroExt32to64, ssa.OpCvt64to32F, types.TINT64}, // go wide to dodge unsigned
twoTypes{types.TUINT64, types.TFLOAT32}: twoOpsAndType{ssa.OpCopy, ssa.OpInvalid, types.TUINT64}, // Cvt64Uto32F, branchy code expansion instead
twoTypes{types.TUINT8, types.TFLOAT64}: twoOpsAndType{ssa.OpZeroExt8to32, ssa.OpCvt32to64F, types.TINT32},
twoTypes{types.TUINT16, types.TFLOAT64}: twoOpsAndType{ssa.OpZeroExt16to32, ssa.OpCvt32to64F, types.TINT32},
twoTypes{types.TUINT32, types.TFLOAT64}: twoOpsAndType{ssa.OpZeroExt32to64, ssa.OpCvt64to64F, types.TINT64}, // go wide to dodge unsigned
twoTypes{types.TUINT64, types.TFLOAT64}: twoOpsAndType{ssa.OpCopy, ssa.OpInvalid, types.TUINT64}, // Cvt64Uto64F, branchy code expansion instead
twoTypes{types.TFLOAT32, types.TUINT8}: twoOpsAndType{ssa.OpCvt32Fto32, ssa.OpTrunc32to8, types.TINT32},
twoTypes{types.TFLOAT32, types.TUINT16}: twoOpsAndType{ssa.OpCvt32Fto32, ssa.OpTrunc32to16, types.TINT32},
twoTypes{types.TFLOAT32, types.TUINT32}: twoOpsAndType{ssa.OpCvt32Fto64, ssa.OpTrunc64to32, types.TINT64}, // go wide to dodge unsigned
twoTypes{types.TFLOAT32, types.TUINT64}: twoOpsAndType{ssa.OpInvalid, ssa.OpCopy, types.TUINT64}, // Cvt32Fto64U, branchy code expansion instead
twoTypes{types.TFLOAT64, types.TUINT8}: twoOpsAndType{ssa.OpCvt64Fto32, ssa.OpTrunc32to8, types.TINT32},
twoTypes{types.TFLOAT64, types.TUINT16}: twoOpsAndType{ssa.OpCvt64Fto32, ssa.OpTrunc32to16, types.TINT32},
twoTypes{types.TFLOAT64, types.TUINT32}: twoOpsAndType{ssa.OpCvt64Fto64, ssa.OpTrunc64to32, types.TINT64}, // go wide to dodge unsigned
twoTypes{types.TFLOAT64, types.TUINT64}: twoOpsAndType{ssa.OpInvalid, ssa.OpCopy, types.TUINT64}, // Cvt64Fto64U, branchy code expansion instead
// float
twoTypes{types.TFLOAT64, types.TFLOAT32}: twoOpsAndType{ssa.OpCvt64Fto32F, ssa.OpCopy, types.TFLOAT32},
twoTypes{types.TFLOAT64, types.TFLOAT64}: twoOpsAndType{ssa.OpRound64F, ssa.OpCopy, types.TFLOAT64},
twoTypes{types.TFLOAT32, types.TFLOAT32}: twoOpsAndType{ssa.OpRound32F, ssa.OpCopy, types.TFLOAT32},
twoTypes{types.TFLOAT32, types.TFLOAT64}: twoOpsAndType{ssa.OpCvt32Fto64F, ssa.OpCopy, types.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{types.TUINT32, types.TFLOAT32}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt32Uto32F, types.TUINT32},
twoTypes{types.TUINT32, types.TFLOAT64}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt32Uto64F, types.TUINT32},
twoTypes{types.TFLOAT32, types.TUINT32}: twoOpsAndType{ssa.OpCvt32Fto32U, ssa.OpCopy, types.TUINT32},
twoTypes{types.TFLOAT64, types.TUINT32}: twoOpsAndType{ssa.OpCvt64Fto32U, ssa.OpCopy, types.TUINT32},
}
// uint64<->float conversions, only on machines that have instructions for that
var uint64fpConvOpToSSA = map[twoTypes]twoOpsAndType{
twoTypes{types.TUINT64, types.TFLOAT32}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt64Uto32F, types.TUINT64},
twoTypes{types.TUINT64, types.TFLOAT64}: twoOpsAndType{ssa.OpCopy, ssa.OpCvt64Uto64F, types.TUINT64},
twoTypes{types.TFLOAT32, types.TUINT64}: twoOpsAndType{ssa.OpCvt32Fto64U, ssa.OpCopy, types.TUINT64},
twoTypes{types.TFLOAT64, types.TUINT64}: twoOpsAndType{ssa.OpCvt64Fto64U, ssa.OpCopy, types.TUINT64},
}
var shiftOpToSSA = map[opAndTwoTypes]ssa.Op{
opAndTwoTypes{ir.OLSH, types.TINT8, types.TUINT8}: ssa.OpLsh8x8,
opAndTwoTypes{ir.OLSH, types.TUINT8, types.TUINT8}: ssa.OpLsh8x8,
opAndTwoTypes{ir.OLSH, types.TINT8, types.TUINT16}: ssa.OpLsh8x16,
opAndTwoTypes{ir.OLSH, types.TUINT8, types.TUINT16}: ssa.OpLsh8x16,
opAndTwoTypes{ir.OLSH, types.TINT8, types.TUINT32}: ssa.OpLsh8x32,
opAndTwoTypes{ir.OLSH, types.TUINT8, types.TUINT32}: ssa.OpLsh8x32,
opAndTwoTypes{ir.OLSH, types.TINT8, types.TUINT64}: ssa.OpLsh8x64,
opAndTwoTypes{ir.OLSH, types.TUINT8, types.TUINT64}: ssa.OpLsh8x64,
opAndTwoTypes{ir.OLSH, types.TINT16, types.TUINT8}: ssa.OpLsh16x8,
opAndTwoTypes{ir.OLSH, types.TUINT16, types.TUINT8}: ssa.OpLsh16x8,
opAndTwoTypes{ir.OLSH, types.TINT16, types.TUINT16}: ssa.OpLsh16x16,
opAndTwoTypes{ir.OLSH, types.TUINT16, types.TUINT16}: ssa.OpLsh16x16,
opAndTwoTypes{ir.OLSH, types.TINT16, types.TUINT32}: ssa.OpLsh16x32,
opAndTwoTypes{ir.OLSH, types.TUINT16, types.TUINT32}: ssa.OpLsh16x32,
opAndTwoTypes{ir.OLSH, types.TINT16, types.TUINT64}: ssa.OpLsh16x64,
opAndTwoTypes{ir.OLSH, types.TUINT16, types.TUINT64}: ssa.OpLsh16x64,
opAndTwoTypes{ir.OLSH, types.TINT32, types.TUINT8}: ssa.OpLsh32x8,
opAndTwoTypes{ir.OLSH, types.TUINT32, types.TUINT8}: ssa.OpLsh32x8,
opAndTwoTypes{ir.OLSH, types.TINT32, types.TUINT16}: ssa.OpLsh32x16,
opAndTwoTypes{ir.OLSH, types.TUINT32, types.TUINT16}: ssa.OpLsh32x16,
opAndTwoTypes{ir.OLSH, types.TINT32, types.TUINT32}: ssa.OpLsh32x32,
opAndTwoTypes{ir.OLSH, types.TUINT32, types.TUINT32}: ssa.OpLsh32x32,
opAndTwoTypes{ir.OLSH, types.TINT32, types.TUINT64}: ssa.OpLsh32x64,
opAndTwoTypes{ir.OLSH, types.TUINT32, types.TUINT64}: ssa.OpLsh32x64,
opAndTwoTypes{ir.OLSH, types.TINT64, types.TUINT8}: ssa.OpLsh64x8,
opAndTwoTypes{ir.OLSH, types.TUINT64, types.TUINT8}: ssa.OpLsh64x8,
opAndTwoTypes{ir.OLSH, types.TINT64, types.TUINT16}: ssa.OpLsh64x16,
opAndTwoTypes{ir.OLSH, types.TUINT64, types.TUINT16}: ssa.OpLsh64x16,
opAndTwoTypes{ir.OLSH, types.TINT64, types.TUINT32}: ssa.OpLsh64x32,
opAndTwoTypes{ir.OLSH, types.TUINT64, types.TUINT32}: ssa.OpLsh64x32,
opAndTwoTypes{ir.OLSH, types.TINT64, types.TUINT64}: ssa.OpLsh64x64,
opAndTwoTypes{ir.OLSH, types.TUINT64, types.TUINT64}: ssa.OpLsh64x64,
opAndTwoTypes{ir.ORSH, types.TINT8, types.TUINT8}: ssa.OpRsh8x8,
opAndTwoTypes{ir.ORSH, types.TUINT8, types.TUINT8}: ssa.OpRsh8Ux8,
opAndTwoTypes{ir.ORSH, types.TINT8, types.TUINT16}: ssa.OpRsh8x16,
opAndTwoTypes{ir.ORSH, types.TUINT8, types.TUINT16}: ssa.OpRsh8Ux16,
opAndTwoTypes{ir.ORSH, types.TINT8, types.TUINT32}: ssa.OpRsh8x32,
opAndTwoTypes{ir.ORSH, types.TUINT8, types.TUINT32}: ssa.OpRsh8Ux32,
opAndTwoTypes{ir.ORSH, types.TINT8, types.TUINT64}: ssa.OpRsh8x64,
opAndTwoTypes{ir.ORSH, types.TUINT8, types.TUINT64}: ssa.OpRsh8Ux64,
opAndTwoTypes{ir.ORSH, types.TINT16, types.TUINT8}: ssa.OpRsh16x8,
opAndTwoTypes{ir.ORSH, types.TUINT16, types.TUINT8}: ssa.OpRsh16Ux8,
opAndTwoTypes{ir.ORSH, types.TINT16, types.TUINT16}: ssa.OpRsh16x16,
opAndTwoTypes{ir.ORSH, types.TUINT16, types.TUINT16}: ssa.OpRsh16Ux16,
opAndTwoTypes{ir.ORSH, types.TINT16, types.TUINT32}: ssa.OpRsh16x32,
opAndTwoTypes{ir.ORSH, types.TUINT16, types.TUINT32}: ssa.OpRsh16Ux32,
opAndTwoTypes{ir.ORSH, types.TINT16, types.TUINT64}: ssa.OpRsh16x64,
opAndTwoTypes{ir.ORSH, types.TUINT16, types.TUINT64}: ssa.OpRsh16Ux64,
opAndTwoTypes{ir.ORSH, types.TINT32, types.TUINT8}: ssa.OpRsh32x8,
opAndTwoTypes{ir.ORSH, types.TUINT32, types.TUINT8}: ssa.OpRsh32Ux8,
opAndTwoTypes{ir.ORSH, types.TINT32, types.TUINT16}: ssa.OpRsh32x16,
opAndTwoTypes{ir.ORSH, types.TUINT32, types.TUINT16}: ssa.OpRsh32Ux16,
opAndTwoTypes{ir.ORSH, types.TINT32, types.TUINT32}: ssa.OpRsh32x32,
opAndTwoTypes{ir.ORSH, types.TUINT32, types.TUINT32}: ssa.OpRsh32Ux32,
opAndTwoTypes{ir.ORSH, types.TINT32, types.TUINT64}: ssa.OpRsh32x64,
opAndTwoTypes{ir.ORSH, types.TUINT32, types.TUINT64}: ssa.OpRsh32Ux64,
opAndTwoTypes{ir.ORSH, types.TINT64, types.TUINT8}: ssa.OpRsh64x8,
opAndTwoTypes{ir.ORSH, types.TUINT64, types.TUINT8}: ssa.OpRsh64Ux8,
opAndTwoTypes{ir.ORSH, types.TINT64, types.TUINT16}: ssa.OpRsh64x16,
opAndTwoTypes{ir.ORSH, types.TUINT64, types.TUINT16}: ssa.OpRsh64Ux16,
opAndTwoTypes{ir.ORSH, types.TINT64, types.TUINT32}: ssa.OpRsh64x32,
opAndTwoTypes{ir.ORSH, types.TUINT64, types.TUINT32}: ssa.OpRsh64Ux32,
opAndTwoTypes{ir.ORSH, types.TINT64, types.TUINT64}: ssa.OpRsh64x64,
opAndTwoTypes{ir.ORSH, types.TUINT64, types.TUINT64}: ssa.OpRsh64Ux64,
}
func (s *state) ssaShiftOp(op ir.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 ir.Node) *ssa.Value {
if ir.HasUniquePos(n) {
// 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.Init())
switch n.Op() {
case ir.OBYTES2STRTMP:
n := n.(*ir.ConvExpr)
slice := s.expr(n.X)
ptr := s.newValue1(ssa.OpSlicePtr, s.f.Config.Types.BytePtr, slice)
len := s.newValue1(ssa.OpSliceLen, types.Types[types.TINT], slice)
return s.newValue2(ssa.OpStringMake, n.Type(), ptr, len)
case ir.OSTR2BYTESTMP:
n := n.(*ir.ConvExpr)
str := s.expr(n.X)
ptr := s.newValue1(ssa.OpStringPtr, s.f.Config.Types.BytePtr, str)
len := s.newValue1(ssa.OpStringLen, types.Types[types.TINT], str)
return s.newValue3(ssa.OpSliceMake, n.Type(), ptr, len, len)
case ir.OCFUNC:
n := n.(*ir.UnaryExpr)
aux := n.X.(*ir.Name).Linksym()
// OCFUNC is used to build function values, which must
// always reference ABIInternal entry points.
if aux.ABI() != obj.ABIInternal {
s.Fatalf("expected ABIInternal: %v", aux.ABI())
}
return s.entryNewValue1A(ssa.OpAddr, n.Type(), aux, s.sb)
case ir.ONAME:
n := n.(*ir.Name)
if n.Class == ir.PFUNC {
// "value" of a function is the address of the function's closure
sym := staticdata.FuncLinksym(n)
return s.entryNewValue1A(ssa.OpAddr, types.NewPtr(n.Type()), sym, s.sb)
}
if s.canSSA(n) {
return s.variable(n, n.Type())
}
return s.load(n.Type(), s.addr(n))
case ir.OLINKSYMOFFSET:
n := n.(*ir.LinksymOffsetExpr)
return s.load(n.Type(), s.addr(n))
case ir.ONIL:
n := n.(*ir.NilExpr)
t := n.Type()
switch {
case t.IsSlice():
return s.constSlice(t)
case t.IsInterface():
return s.constInterface(t)
default:
return s.constNil(t)
}
case ir.OLITERAL:
switch u := n.Val(); u.Kind() {
case constant.Int:
i := ir.IntVal(n.Type(), u)
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 constant.String:
i := constant.StringVal(u)
if i == "" {
return s.constEmptyString(n.Type())
}
return s.entryNewValue0A(ssa.OpConstString, n.Type(), ssa.StringToAux(i))
case constant.Bool:
return s.constBool(constant.BoolVal(u))
case constant.Float:
f, _ := constant.Float64Val(u)
switch n.Type().Size() {
case 4:
return s.constFloat32(n.Type(), f)
case 8:
return s.constFloat64(n.Type(), f)
default:
s.Fatalf("bad float size %d", n.Type().Size())
return nil
}
case constant.Complex:
re, _ := constant.Float64Val(constant.Real(u))
im, _ := constant.Float64Val(constant.Imag(u))
switch n.Type().Size() {
case 8:
pt := types.Types[types.TFLOAT32]
return s.newValue2(ssa.OpComplexMake, n.Type(),
s.constFloat32(pt, re),
s.constFloat32(pt, im))
case 16:
pt := types.Types[types.TFLOAT64]
return s.newValue2(ssa.OpComplexMake, n.Type(),
s.constFloat64(pt, re),
s.constFloat64(pt, im))
default:
s.Fatalf("bad complex size %d", n.Type().Size())
return nil
}
default:
s.Fatalf("unhandled OLITERAL %v", u.Kind())
return nil
}
case ir.OCONVNOP:
n := n.(*ir.ConvExpr)
to := n.Type()
from := n.X.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.X)
if to == from {
return x
}
// 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.Kind() == types.TFUNC && from.IsPtrShaped() {
return v
}
// named <--> unnamed type or typed <--> untyped const
if from.Kind() == to.Kind() {
return v
}
// unsafe.Pointer <--> *T
if to.IsUnsafePtr() && from.IsPtrShaped() || from.IsUnsafePtr() && to.IsPtrShaped() {
return v
}
// map <--> *hmap
if to.Kind() == types.TMAP && from.IsPtr() &&
to.MapType().Hmap == from.Elem() {
return v
}
types.CalcSize(from)
types.CalcSize(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.Kind()) != etypesign(to.Kind()) {
s.Fatalf("CONVNOP sign mismatch %v (%s) -> %v (%s)\n", from, from.Kind(), to, to.Kind())
return nil
}
if base.Flag.Cfg.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.Kind()) == 0 {
s.Fatalf("CONVNOP unrecognized non-integer %v -> %v\n", from, to)
return nil
}
// integer, same width, same sign
return v
case ir.OCONV:
n := n.(*ir.ConvExpr)
x := s.expr(n.X)
ft := n.X.Type() // from type
tt := n.Type() // to type
if ft.IsBoolean() && tt.IsKind(types.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 && Arch.LinkArch.Family != sys.MIPS && !s.softFloat {
if conv1, ok1 := fpConvOpToSSA32[twoTypes{s.concreteEtype(ft), s.concreteEtype(tt)}]; ok1 {
conv = conv1
}
}
if Arch.LinkArch.Family == sys.ARM64 || Arch.LinkArch.Family == sys.Wasm || Arch.LinkArch.Family == sys.S390X || s.softFloat {
if conv1, ok1 := uint64fpConvOpToSSA[twoTypes{s.concreteEtype(ft), s.concreteEtype(tt)}]; ok1 {
conv = conv1
}
}
if Arch.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 := types.FloatForComplex(ft)
ttp := types.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.X.Type().Kind(), n.Type().Kind())
return nil
case ir.ODOTTYPE:
n := n.(*ir.TypeAssertExpr)
res, _ := s.dottype(n, false)
return res
// binary ops
case ir.OLT, ir.OEQ, ir.ONE, ir.OLE, ir.OGE, ir.OGT:
n := n.(*ir.BinaryExpr)
a := s.expr(n.X)
b := s.expr(n.Y)
if n.X.Type().IsComplex() {
pt := types.FloatForComplex(n.X.Type())
op := s.ssaOp(ir.OEQ, pt)
r := s.newValueOrSfCall2(op, types.Types[types.TBOOL], s.newValue1(ssa.OpComplexReal, pt, a), s.newValue1(ssa.OpComplexReal, pt, b))
i := s.newValueOrSfCall2(op, types.Types[types.TBOOL], s.newValue1(ssa.OpComplexImag, pt, a), s.newValue1(ssa.OpComplexImag, pt, b))
c := s.newValue2(ssa.OpAndB, types.Types[types.TBOOL], r, i)
switch n.Op() {
case ir.OEQ:
return c
case ir.ONE:
return s.newValue1(ssa.OpNot, types.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 ir.OGE:
op, a, b = ir.OLE, b, a
case ir.OGT:
op, a, b = ir.OLT, b, a
}
if n.X.Type().IsFloat() {
// float comparison
return s.newValueOrSfCall2(s.ssaOp(op, n.X.Type()), types.Types[types.TBOOL], a, b)
}
// integer comparison
return s.newValue2(s.ssaOp(op, n.X.Type()), types.Types[types.TBOOL], a, b)
case ir.OMUL:
n := n.(*ir.BinaryExpr)
a := s.expr(n.X)
b := s.expr(n.Y)
if n.Type().IsComplex() {
mulop := ssa.OpMul64F
addop := ssa.OpAdd64F
subop := ssa.OpSub64F
pt := types.FloatForComplex(n.Type()) // Could be Float32 or Float64
wt := types.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 ir.ODIV:
n := n.(*ir.BinaryExpr)
a := s.expr(n.X)
b := s.expr(n.Y)
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 := types.FloatForComplex(n.Type()) // Could be Float32 or Float64
wt := types.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 ir.OMOD:
n := n.(*ir.BinaryExpr)
a := s.expr(n.X)
b := s.expr(n.Y)
return s.intDivide(n, a, b)
case ir.OADD, ir.OSUB:
n := n.(*ir.BinaryExpr)
a := s.expr(n.X)
b := s.expr(n.Y)
if n.Type().IsComplex() {
pt := types.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 ir.OAND, ir.OOR, ir.OXOR:
n := n.(*ir.BinaryExpr)
a := s.expr(n.X)
b := s.expr(n.Y)
return s.newValue2(s.ssaOp(n.Op(), n.Type()), a.Type, a, b)
case ir.OANDNOT:
n := n.(*ir.BinaryExpr)
a := s.expr(n.X)
b := s.expr(n.Y)
b = s.newValue1(s.ssaOp(ir.OBITNOT, b.Type), b.Type, b)
return s.newValue2(s.ssaOp(ir.OAND, n.Type()), a.Type, a, b)
case ir.OLSH, ir.ORSH:
n := n.(*ir.BinaryExpr)
a := s.expr(n.X)
b := s.expr(n.Y)
bt := b.Type
if bt.IsSigned() {
cmp := s.newValue2(s.ssaOp(ir.OLE, bt), types.Types[types.TBOOL], s.zeroVal(bt), b)
s.check(cmp, ir.Syms.Panicshift)
bt = bt.ToUnsigned()
}
return s.newValue2(s.ssaShiftOp(n.Op(), n.Type(), bt), a.Type, a, b)
case ir.OANDAND, ir.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.
n := n.(*ir.LogicalExpr)
el := s.expr(n.X)
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() == ir.OANDAND {
b.AddEdgeTo(bRight)
b.AddEdgeTo(bResult)
} else if n.Op() == ir.OOROR {
b.AddEdgeTo(bResult)
b.AddEdgeTo(bRight)
}
s.startBlock(bRight)
er := s.expr(n.Y)
s.vars[n] = er
b = s.endBlock()
b.AddEdgeTo(bResult)
s.startBlock(bResult)
return s.variable(n, types.Types[types.TBOOL])
case ir.OCOMPLEX:
n := n.(*ir.BinaryExpr)
r := s.expr(n.X)
i := s.expr(n.Y)
return s.newValue2(ssa.OpComplexMake, n.Type(), r, i)
// unary ops
case ir.ONEG:
n := n.(*ir.UnaryExpr)
a := s.expr(n.X)
if n.Type().IsComplex() {
tp := types.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 ir.ONOT, ir.OBITNOT:
n := n.(*ir.UnaryExpr)
a := s.expr(n.X)
return s.newValue1(s.ssaOp(n.Op(), n.Type()), a.Type, a)
case ir.OIMAG, ir.OREAL:
n := n.(*ir.UnaryExpr)
a := s.expr(n.X)
return s.newValue1(s.ssaOp(n.Op(), n.X.Type()), n.Type(), a)
case ir.OPLUS:
n := n.(*ir.UnaryExpr)
return s.expr(n.X)
case ir.OADDR:
n := n.(*ir.AddrExpr)
return s.addr(n.X)
case ir.ORESULT:
n := n.(*ir.ResultExpr)
if s.prevCall == nil || s.prevCall.Op != ssa.OpStaticLECall && s.prevCall.Op != ssa.OpInterLECall && s.prevCall.Op != ssa.OpClosureLECall {
panic("Expected to see a previous call")
}
which := n.Index
if which == -1 {
panic(fmt.Errorf("ORESULT %v does not match call %s", n, s.prevCall))
}
return s.resultOfCall(s.prevCall, which, n.Type())
case ir.ODEREF:
n := n.(*ir.StarExpr)
p := s.exprPtr(n.X, n.Bounded(), n.Pos())
return s.load(n.Type(), p)
case ir.ODOT:
n := n.(*ir.SelectorExpr)
if n.X.Op() == ir.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 !ir.IsZero(n.X) {
s.Fatalf("literal with nonzero value in SSA: %v", n.X)
}
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 ir.IsAddressable(n) && !s.canSSA(n) {
p := s.addr(n)
return s.load(n.Type(), p)
}
v := s.expr(n.X)
return s.newValue1I(ssa.OpStructSelect, n.Type(), int64(fieldIdx(n)), v)
case ir.ODOTPTR:
n := n.(*ir.SelectorExpr)
p := s.exprPtr(n.X, n.Bounded(), n.Pos())
p = s.newValue1I(ssa.OpOffPtr, types.NewPtr(n.Type()), n.Offset(), p)
return s.load(n.Type(), p)
case ir.OINDEX:
n := n.(*ir.IndexExpr)
switch {
case n.X.Type().IsString():
if n.Bounded() && ir.IsConst(n.X, constant.String) && ir.IsConst(n.Index, constant.Int) {
// 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[types.TUINT8], int64(int8(ir.StringVal(n.X)[ir.Int64Val(n.Index)])))
}
a := s.expr(n.X)
i := s.expr(n.Index)
len := s.newValue1(ssa.OpStringLen, types.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 ir.IsConst(n.Index, constant.Int) {
ptr = s.newValue1I(ssa.OpOffPtr, ptrtyp, ir.Int64Val(n.Index), ptr)
} else {
ptr = s.newValue2(ssa.OpAddPtr, ptrtyp, ptr, i)
}
return s.load(types.Types[types.TUINT8], ptr)
case n.X.Type().IsSlice():
p := s.addr(n)
return s.load(n.X.Type().Elem(), p)
case n.X.Type().IsArray():
if TypeOK(n.X.Type()) {
// SSA can handle arrays of length at most 1.
bound := n.X.Type().NumElem()
a := s.expr(n.X)
i := s.expr(n.Index)
if bound == 0 {
// Bounds check will never succeed. Might as well
// use constants for the bounds check.
z := s.constInt(types.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[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.X.Type().Elem(), p)
default:
s.Fatalf("bad type for index %v", n.X.Type())
return nil
}
case ir.OLEN, ir.OCAP:
n := n.(*ir.UnaryExpr)
switch {
case n.X.Type().IsSlice():
op := ssa.OpSliceLen
if n.Op() == ir.OCAP {
op = ssa.OpSliceCap
}
return s.newValue1(op, types.Types[types.TINT], s.expr(n.X))
case n.X.Type().IsString(): // string; not reachable for OCAP
return s.newValue1(ssa.OpStringLen, types.Types[types.TINT], s.expr(n.X))
case n.X.Type().IsMap(), n.X.Type().IsChan():
return s.referenceTypeBuiltin(n, s.expr(n.X))
default: // array
return s.constInt(types.Types[types.TINT], n.X.Type().NumElem())
}
case ir.OSPTR:
n := n.(*ir.UnaryExpr)
a := s.expr(n.X)
if n.X.Type().IsSlice() {
return s.newValue1(ssa.OpSlicePtr, n.Type(), a)
} else {
return s.newValue1(ssa.OpStringPtr, n.Type(), a)
}
case ir.OITAB:
n := n.(*ir.UnaryExpr)
a := s.expr(n.X)
return s.newValue1(ssa.OpITab, n.Type(), a)
case ir.OIDATA:
n := n.(*ir.UnaryExpr)
a := s.expr(n.X)
return s.newValue1(ssa.OpIData, n.Type(), a)
case ir.OEFACE:
n := n.(*ir.BinaryExpr)
tab := s.expr(n.X)
data := s.expr(n.Y)
return s.newValue2(ssa.OpIMake, n.Type(), tab, data)
case ir.OSLICEHEADER:
n := n.(*ir.SliceHeaderExpr)
p := s.expr(n.Ptr)
l := s.expr(n.Len)
c := s.expr(n.Cap)
return s.newValue3(ssa.OpSliceMake, n.Type(), p, l, c)
case ir.OSLICE, ir.OSLICEARR, ir.OSLICE3, ir.OSLICE3ARR:
n := n.(*ir.SliceExpr)
v := s.expr(n.X)
var i, j, k *ssa.Value
if n.Low != nil {
i = s.expr(n.Low)
}
if n.High != nil {
j = s.expr(n.High)
}
if n.Max != nil {
k = s.expr(n.Max)
}
p, l, c := s.slice(v, i, j, k, n.Bounded())
return s.newValue3(ssa.OpSliceMake, n.Type(), p, l, c)
case ir.OSLICESTR:
n := n.(*ir.SliceExpr)
v := s.expr(n.X)
var i, j *ssa.Value
if n.Low != nil {
i = s.expr(n.Low)
}
if n.High != nil {
j = s.expr(n.High)
}
p, l, _ := s.slice(v, i, j, nil, n.Bounded())
return s.newValue2(ssa.OpStringMake, n.Type(), p, l)
case ir.OSLICE2ARRPTR:
// if arrlen > slice.len {
// panic(...)
// }
// slice.ptr
n := n.(*ir.ConvExpr)
v := s.expr(n.X)
arrlen := s.constInt(types.Types[types.TINT], n.Type().Elem().NumElem())
cap := s.newValue1(ssa.OpSliceLen, types.Types[types.TINT], v)
s.boundsCheck(arrlen, cap, ssa.BoundsConvert, false)
return s.newValue1(ssa.OpSlicePtrUnchecked, types.Types[types.TINT], v)
case ir.OCALLFUNC:
n := n.(*ir.CallExpr)
if ir.IsIntrinsicCall(n) {
return s.intrinsicCall(n)
}
fallthrough
case ir.OCALLINTER, ir.OCALLMETH:
n := n.(*ir.CallExpr)
return s.callResult(n, callNormal)
case ir.OGETG:
n := n.(*ir.CallExpr)
return s.newValue1(ssa.OpGetG, n.Type(), s.mem())
case ir.OAPPEND:
return s.append(n.(*ir.CallExpr), false)
case ir.OSTRUCTLIT, ir.OARRAYLIT:
// All literals with nonzero fields have already been
// rewritten during walk. Any that remain are just T{}
// or equivalents. Use the zero value.
n := n.(*ir.CompLitExpr)
if !ir.IsZero(n) {
s.Fatalf("literal with nonzero value in SSA: %v", n)
}
return s.zeroVal(n.Type())
case ir.ONEW:
n := n.(*ir.UnaryExpr)
return s.newObject(n.Type().Elem())
default:
s.Fatalf("unhandled expr %v", n.Op())
return nil
}
}
func (s *state) resultOfCall(c *ssa.Value, which int64, t *types.Type) *ssa.Value {
aux := c.Aux.(*ssa.AuxCall)
pa := aux.ParamAssignmentForResult(which)
// TODO(register args) determine if in-memory TypeOK is better loaded early from SelectNAddr or later when SelectN is expanded.
// SelectN is better for pattern-matching and possible call-aware analysis we might want to do in the future.
if len(pa.Registers) == 0 && !TypeOK(t) {
addr := s.newValue1I(ssa.OpSelectNAddr, types.NewPtr(t), which, c)
return s.rawLoad(t, addr)
}
return s.newValue1I(ssa.OpSelectN, t, which, c)
}
func (s *state) resultAddrOfCall(c *ssa.Value, which int64, t *types.Type) *ssa.Value {
aux := c.Aux.(*ssa.AuxCall)
pa := aux.ParamAssignmentForResult(which)
if len(pa.Registers) == 0 {
return s.newValue1I(ssa.OpSelectNAddr, types.NewPtr(t), which, c)
}
_, addr := s.temp(c.Pos, t)
rval := s.newValue1I(ssa.OpSelectN, t, which, c)
s.vars[memVar] = s.newValue3Apos(ssa.OpStore, types.TypeMem, t, addr, rval, s.mem(), false)
return addr
}
// 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 *ir.CallExpr, 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.Args[0] // 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(len(n.Args) - 1)
p := s.newValue1(ssa.OpSlicePtr, pt, slice)
l := s.newValue1(ssa.OpSliceLen, types.Types[types.TINT], slice)
c := s.newValue1(ssa.OpSliceCap, types.Types[types.TINT], slice)
nl := s.newValue2(s.ssaOp(ir.OADD, types.Types[types.TINT]), types.Types[types.TINT], l, s.constInt(types.Types[types.TINT], nargs))
cmp := s.newValue2(s.ssaOp(ir.OLT, types.Types[types.TUINT]), types.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.X)
r := s.rtcall(ir.Syms.Growslice, true, []*types.Type{pt, types.Types[types.TINT], types.Types[types.TINT]}, taddr, p, l, c, nl)
if inplace {
if sn.Op() == ir.ONAME {
sn := sn.(*ir.Name)
if sn.Class != ir.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, types.SliceCapOffset, addr)
s.store(types.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(ir.OADD, types.Types[types.TINT]), types.Types[types.TINT], r[1], s.constInt(types.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[types.TINT]) // generates phi for len
nl = s.newValue2(s.ssaOp(ir.OADD, types.Types[types.TINT]), types.Types[types.TINT], l, s.constInt(types.Types[types.TINT], nargs))
lenaddr := s.newValue1I(ssa.OpOffPtr, s.f.Config.Types.IntPtr, types.SliceLenOffset, addr)
s.store(types.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.Args[1:] {
if TypeOK(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[types.TINT]) // generates phi for nl
c = s.variable(capVar, types.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[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 ir.Node, yes, no *ssa.Block, likely int8) {
switch cond.Op() {
case ir.OANDAND:
cond := cond.(*ir.LogicalExpr)
mid := s.f.NewBlock(ssa.BlockPlain)
s.stmtList(cond.Init())
s.condBranch(cond.X, mid, no, max8(likely, 0))
s.startBlock(mid)
s.condBranch(cond.Y, 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 ir.OOROR:
cond := cond.(*ir.LogicalExpr)
mid := s.f.NewBlock(ssa.BlockPlain)
s.stmtList(cond.Init())
s.condBranch(cond.X, yes, mid, min8(likely, 0))
s.startBlock(mid)
s.condBranch(cond.Y, 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 ir.ONOT:
cond := cond.(*ir.UnaryExpr)
s.stmtList(cond.Init())
s.condBranch(cond.X, no, yes, -likely)
return
case ir.OCONVNOP:
cond := cond.(*ir.ConvExpr)
s.stmtList(cond.Init())
s.condBranch(cond.X, yes, no, 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 ir.Node, right *ssa.Value, deref bool, skip skipMask) {
if left.Op() == ir.ONAME && ir.IsBlank(left) {
return
}
t := left.Type()
types.CalcSize(t)
if s.canSSA(left) {
if deref {
s.Fatalf("can SSA LHS %v but not RHS %s", left, right)
}
if left.Op() == ir.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.
left := left.(*ir.SelectorExpr)
t := left.X.Type()
nf := t.NumFields()
idx := fieldIdx(left)
// Grab old value of structure.
old := s.expr(left.X)
// 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.X, new, false, 0)
// TODO: do we need to update named values here?
return
}
if left.Op() == ir.OINDEX && left.(*ir.IndexExpr).X.Type().IsArray() {
left := left.(*ir.IndexExpr)
s.pushLine(left.Pos())
defer s.popLine()
// We're assigning to an element of an ssa-able array.
// a[i] = v
t := left.X.Type()
n := t.NumElem()
i := s.expr(left.Index) // 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[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[types.TINT], 1)
s.boundsCheck(i, len, ssa.BoundsIndex, false) // checks i == 0
v := s.newValue1(ssa.OpArrayMake1, t, right)
s.assign(left.X, v, false, 0)
return
}
left := left.(*ir.Name)
// 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, ok := clobberBase(left).(*ir.Name); ok && base.OnStack() && skip == 0 {
s.vars[memVar] = s.newValue1Apos(ssa.OpVarDef, types.TypeMem, base, s.mem(), !ir.IsAutoTmp(base))
}
// Left is not ssa-able. Compute its address.
addr := s.addr(left)
if ir.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[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, !ir.IsAutoTmp(left))
}
// 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[types.TFLOAT32], 0)
return s.entryNewValue2(ssa.OpComplexMake, t, z, z)
case 16:
z := s.constFloat64(types.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.Kind
}
var softFloatOps map[ssa.Op]sfRtCallDef
func softfloatInit() {
// Some of these operations get transformed by sfcall.
softFloatOps = map[ssa.Op]sfRtCallDef{
ssa.OpAdd32F: sfRtCallDef{typecheck.LookupRuntimeFunc("fadd32"), types.TFLOAT32},
ssa.OpAdd64F: sfRtCallDef{typecheck.LookupRuntimeFunc("fadd64"), types.TFLOAT64},
ssa.OpSub32F: sfRtCallDef{typecheck.LookupRuntimeFunc("fadd32"), types.TFLOAT32},
ssa.OpSub64F: sfRtCallDef{typecheck.LookupRuntimeFunc("fadd64"), types.TFLOAT64},
ssa.OpMul32F: sfRtCallDef{typecheck.LookupRuntimeFunc("fmul32"), types.TFLOAT32},
ssa.OpMul64F: sfRtCallDef{typecheck.LookupRuntimeFunc("fmul64"), types.TFLOAT64},
ssa.OpDiv32F: sfRtCallDef{typecheck.LookupRuntimeFunc("fdiv32"), types.TFLOAT32},
ssa.OpDiv64F: sfRtCallDef{typecheck.LookupRuntimeFunc("fdiv64"), types.TFLOAT64},
ssa.OpEq64F: sfRtCallDef{typecheck.LookupRuntimeFunc("feq64"), types.TBOOL},
ssa.OpEq32F: sfRtCallDef{typecheck.LookupRuntimeFunc("feq32"), types.TBOOL},
ssa.OpNeq64F: sfRtCallDef{typecheck.LookupRuntimeFunc("feq64"), types.TBOOL},
ssa.OpNeq32F: sfRtCallDef{typecheck.LookupRuntimeFunc("feq32"), types.TBOOL},
ssa.OpLess64F: sfRtCallDef{typecheck.LookupRuntimeFunc("fgt64"), types.TBOOL},
ssa.OpLess32F: sfRtCallDef{typecheck.LookupRuntimeFunc("fgt32"), types.TBOOL},
ssa.OpLeq64F: sfRtCallDef{typecheck.LookupRuntimeFunc("fge64"), types.TBOOL},
ssa.OpLeq32F: sfRtCallDef{typecheck.LookupRuntimeFunc("fge32"), types.TBOOL},
ssa.OpCvt32to32F: sfRtCallDef{typecheck.LookupRuntimeFunc("fint32to32"), types.TFLOAT32},
ssa.OpCvt32Fto32: sfRtCallDef{typecheck.LookupRuntimeFunc("f32toint32"), types.TINT32},
ssa.OpCvt64to32F: sfRtCallDef{typecheck.LookupRuntimeFunc("fint64to32"), types.TFLOAT32},
ssa.OpCvt32Fto64: sfRtCallDef{typecheck.LookupRuntimeFunc("f32toint64"), types.TINT64},
ssa.OpCvt64Uto32F: sfRtCallDef{typecheck.LookupRuntimeFunc("fuint64to32"), types.TFLOAT32},
ssa.OpCvt32Fto64U: sfRtCallDef{typecheck.LookupRuntimeFunc("f32touint64"), types.TUINT64},
ssa.OpCvt32to64F: sfRtCallDef{typecheck.LookupRuntimeFunc("fint32to64"), types.TFLOAT64},
ssa.OpCvt64Fto32: sfRtCallDef{typecheck.LookupRuntimeFunc("f64toint32"), types.TINT32},
ssa.OpCvt64to64F: sfRtCallDef{typecheck.LookupRuntimeFunc("fint64to64"), types.TFLOAT64},
ssa.OpCvt64Fto64: sfRtCallDef{typecheck.LookupRuntimeFunc("f64toint64"), types.TINT64},
ssa.OpCvt64Uto64F: sfRtCallDef{typecheck.LookupRuntimeFunc("fuint64to64"), types.TFLOAT64},