cmd/compile, cmd/internal/obj: centralize knowledge of size of fixed part of stack
Shared libraries on ppc64le will require a larger minimum stack frame (because
the ABI mandates that the TOC pointer is available at 24(R1)). Part 2a of
preparing for that is to have all bits of arch-independent and ppc64-specific
codegen that need to know call a function to find out.
Change-Id: I55899f73037e92227813c491049a3bd6f30bd41f
Reviewed-on: https://go-review.googlesource.com/15524
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/src/cmd/compile/internal/gc/cgen.go b/src/cmd/compile/internal/gc/cgen.go
index 951f84f..d6538a3 100644
--- a/src/cmd/compile/internal/gc/cgen.go
+++ b/src/cmd/compile/internal/gc/cgen.go
@@ -810,10 +810,7 @@
a := &p.To
a.Type = obj.TYPE_MEM
a.Reg = int16(Thearch.REGSP)
- a.Offset = 0
- if HasLinkRegister() {
- a.Offset += int64(Widthptr)
- }
+ a.Offset = Ctxt.FixedFrameSize()
p2 := Thearch.Gins(Thearch.Optoas(OAS, Types[Tptr]), &src, nil)
p2.To = p.To
p2.To.Offset += int64(Widthptr)
@@ -849,10 +846,7 @@
a := &p.To
a.Type = obj.TYPE_MEM
a.Reg = int16(Thearch.REGSP)
- a.Offset = 0
- if HasLinkRegister() {
- a.Offset += int64(Widthptr)
- }
+ a.Offset = Ctxt.FixedFrameSize()
if needType {
a.Offset += int64(Widthptr)
}
@@ -1686,10 +1680,7 @@
a.Op = OINDREG
a.Reg = int16(Thearch.REGSP)
a.Addable = true
- a.Xoffset = fp.Width
- if HasLinkRegister() {
- a.Xoffset += int64(Ctxt.Arch.Ptrsize)
- }
+ a.Xoffset = fp.Width + Ctxt.FixedFrameSize()
a.Type = n.Type
return
@@ -2219,11 +2210,7 @@
var flist Iter
t = Structfirst(&flist, Getoutarg(t))
if t != nil {
- w := t.Width
- if HasLinkRegister() {
- w += int64(Ctxt.Arch.Ptrsize)
- }
- return w
+ return t.Width + Ctxt.FixedFrameSize()
}
}
@@ -2379,17 +2366,11 @@
// size of arguments at 0(SP)
stk.Op = OINDREG
stk.Reg = int16(Thearch.REGSP)
- stk.Xoffset = 0
- if HasLinkRegister() {
- stk.Xoffset += int64(Ctxt.Arch.Ptrsize)
- }
+ stk.Xoffset = Ctxt.FixedFrameSize()
Thearch.Ginscon(Thearch.Optoas(OAS, Types[TINT32]), int64(Argsize(f.Type)), &stk)
// FuncVal* at 8(SP)
- stk.Xoffset = int64(Widthptr)
- if HasLinkRegister() {
- stk.Xoffset += int64(Ctxt.Arch.Ptrsize)
- }
+ stk.Xoffset = int64(Widthptr) + Ctxt.FixedFrameSize()
var reg Node
Nodreg(®, Types[Tptr], Thearch.REGCALLX2)
@@ -2447,10 +2428,7 @@
var nodsp Node
Nodindreg(&nodsp, Types[Tptr], Thearch.REGSP)
- nodsp.Xoffset = 0
- if HasLinkRegister() {
- nodsp.Xoffset += int64(Ctxt.Arch.Ptrsize)
- }
+ nodsp.Xoffset = Ctxt.FixedFrameSize()
if proc != 0 {
nodsp.Xoffset += 2 * int64(Widthptr) // leave room for size & fn
}
@@ -2541,11 +2519,6 @@
Ginscall(n.Left, proc)
}
-func HasLinkRegister() bool {
- c := Ctxt.Arch.Thechar
- return c != '6' && c != '8'
-}
-
/*
* call to n has already been generated.
* generate:
@@ -2568,10 +2541,7 @@
nod.Reg = int16(Thearch.REGSP)
nod.Addable = true
- nod.Xoffset = fp.Width
- if HasLinkRegister() {
- nod.Xoffset += int64(Ctxt.Arch.Ptrsize)
- }
+ nod.Xoffset = fp.Width + Ctxt.FixedFrameSize()
nod.Type = fp.Type
Cgen_as(res, &nod)
}
@@ -2597,10 +2567,7 @@
nod1.Op = OINDREG
nod1.Reg = int16(Thearch.REGSP)
nod1.Addable = true
- nod1.Xoffset = fp.Width
- if HasLinkRegister() {
- nod1.Xoffset += int64(Ctxt.Arch.Ptrsize)
- }
+ nod1.Xoffset = fp.Width + Ctxt.FixedFrameSize()
nod1.Type = fp.Type
if res.Op != OREGISTER {
@@ -2858,10 +2825,7 @@
arg.Op = OINDREG
arg.Reg = int16(Thearch.REGSP)
arg.Addable = true
- arg.Xoffset = 0
- if HasLinkRegister() {
- arg.Xoffset = int64(Ctxt.Arch.Ptrsize)
- }
+ arg.Xoffset = Ctxt.FixedFrameSize()
arg.Type = Ptrto(Types[TUINT8])
Cgen(typename(res.Type), &arg)
arg.Xoffset += int64(Widthptr)
diff --git a/src/cmd/compile/internal/gc/gsubr.go b/src/cmd/compile/internal/gc/gsubr.go
index 37c2e99..5c057d5 100644
--- a/src/cmd/compile/internal/gc/gsubr.go
+++ b/src/cmd/compile/internal/gc/gsubr.go
@@ -568,9 +568,7 @@
n.Op = OINDREG
n.Reg = int16(Thearch.REGSP)
- if HasLinkRegister() {
- n.Xoffset += int64(Ctxt.Arch.Ptrsize)
- }
+ n.Xoffset += Ctxt.FixedFrameSize()
case 1: // input arg
n.Class = PPARAM
diff --git a/src/cmd/compile/internal/ppc64/ggen.go b/src/cmd/compile/internal/ppc64/ggen.go
index 195f2b0..d0bdebb 100644
--- a/src/cmd/compile/internal/ppc64/ggen.go
+++ b/src/cmd/compile/internal/ppc64/ggen.go
@@ -69,10 +69,10 @@
}
if cnt < int64(4*gc.Widthptr) {
for i := int64(0); i < cnt; i += int64(gc.Widthptr) {
- p = appendpp(p, ppc64.AMOVD, obj.TYPE_REG, ppc64.REGZERO, 0, obj.TYPE_MEM, ppc64.REGSP, 8+frame+lo+i)
+ p = appendpp(p, ppc64.AMOVD, obj.TYPE_REG, ppc64.REGZERO, 0, obj.TYPE_MEM, ppc64.REGSP, gc.Ctxt.FixedFrameSize()+frame+lo+i)
}
} else if cnt <= int64(128*gc.Widthptr) {
- p = appendpp(p, ppc64.AADD, obj.TYPE_CONST, 0, 8+frame+lo-8, obj.TYPE_REG, ppc64.REGRT1, 0)
+ p = appendpp(p, ppc64.AADD, obj.TYPE_CONST, 0, gc.Ctxt.FixedFrameSize()+frame+lo-8, obj.TYPE_REG, ppc64.REGRT1, 0)
p.Reg = ppc64.REGSP
p = appendpp(p, obj.ADUFFZERO, obj.TYPE_NONE, 0, 0, obj.TYPE_MEM, 0, 0)
f := gc.Sysfunc("duffzero")
@@ -80,7 +80,7 @@
gc.Afunclit(&p.To, f)
p.To.Offset = 4 * (128 - cnt/int64(gc.Widthptr))
} else {
- p = appendpp(p, ppc64.AMOVD, obj.TYPE_CONST, 0, 8+frame+lo-8, obj.TYPE_REG, ppc64.REGTMP, 0)
+ p = appendpp(p, ppc64.AMOVD, obj.TYPE_CONST, 0, gc.Ctxt.FixedFrameSize()+frame+lo-8, obj.TYPE_REG, ppc64.REGTMP, 0)
p = appendpp(p, ppc64.AADD, obj.TYPE_REG, ppc64.REGTMP, 0, obj.TYPE_REG, ppc64.REGRT1, 0)
p.Reg = ppc64.REGSP
p = appendpp(p, ppc64.AMOVD, obj.TYPE_CONST, 0, cnt, obj.TYPE_REG, ppc64.REGTMP, 0)
diff --git a/src/cmd/internal/obj/link.go b/src/cmd/internal/obj/link.go
index 75b8d5e..22dbc86 100644
--- a/src/cmd/internal/obj/link.go
+++ b/src/cmd/internal/obj/link.go
@@ -523,6 +523,19 @@
Etextp *LSym
}
+// The smallest possible offset from the hardware stack pointer to a local
+// variable on the stack. Architectures that use a link register save its value
+// on the stack in the function prologue and so always have a pointer between
+// the hardware stack pointer and the local variable area.
+func (ctxt *Link) FixedFrameSize() int64 {
+ switch ctxt.Arch.Thechar {
+ case '6', '8':
+ return 0
+ default:
+ return int64(ctxt.Arch.Ptrsize)
+ }
+}
+
type SymVer struct {
Name string
Version int // TODO: make int16 to match LSym.Version?
diff --git a/src/cmd/internal/obj/ppc64/asm9.go b/src/cmd/internal/obj/ppc64/asm9.go
index 43ff683..c7bd835 100644
--- a/src/cmd/internal/obj/ppc64/asm9.go
+++ b/src/cmd/internal/obj/ppc64/asm9.go
@@ -595,7 +595,7 @@
return C_LAUTO
case obj.NAME_PARAM:
- ctxt.Instoffset = int64(ctxt.Autosize) + a.Offset + 8
+ ctxt.Instoffset = int64(ctxt.Autosize) + a.Offset + ctxt.FixedFrameSize()
if ctxt.Instoffset >= -BIG && ctxt.Instoffset < BIG {
return C_SAUTO
}
@@ -658,7 +658,7 @@
return C_LACON
case obj.NAME_PARAM:
- ctxt.Instoffset = int64(ctxt.Autosize) + a.Offset + 8
+ ctxt.Instoffset = int64(ctxt.Autosize) + a.Offset + ctxt.FixedFrameSize()
if ctxt.Instoffset >= -BIG && ctxt.Instoffset < BIG {
return C_SACON
}
diff --git a/src/cmd/internal/obj/ppc64/obj9.go b/src/cmd/internal/obj/ppc64/obj9.go
index e1f3435..e72832d 100644
--- a/src/cmd/internal/obj/ppc64/obj9.go
+++ b/src/cmd/internal/obj/ppc64/obj9.go
@@ -337,7 +337,7 @@
if p.From3.Offset&obj.NOFRAME == 0 {
// If there is a stack frame at all, it includes
// space to save the LR.
- autosize += 8
+ autosize += int32(ctxt.FixedFrameSize())
}
p.To.Offset = int64(autosize)
@@ -445,7 +445,7 @@
q = obj.Appendp(ctxt, q)
q.As = AADD
q.From.Type = obj.TYPE_CONST
- q.From.Offset = int64(autosize) + 8
+ q.From.Offset = int64(autosize) + ctxt.FixedFrameSize()
q.Reg = REGSP
q.To.Type = obj.TYPE_REG
q.To.Reg = REG_R5
@@ -465,7 +465,7 @@
q = obj.Appendp(ctxt, q)
q.As = AADD
q.From.Type = obj.TYPE_CONST
- q.From.Offset = 8
+ q.From.Offset = ctxt.FixedFrameSize()
q.Reg = REGSP
q.To.Type = obj.TYPE_REG
q.To.Reg = REG_R6
