mirror of
https://github.com/42wim/matterbridge.git
synced 2024-11-26 12:42:03 -08:00
1006 lines
22 KiB
Go
1006 lines
22 KiB
Go
// cmd/7l/noop.c, cmd/7l/obj.c, cmd/ld/pass.c from Vita Nuova.
|
|
// https://code.google.com/p/ken-cc/source/browse/
|
|
//
|
|
// Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved.
|
|
// Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
|
|
// Portions Copyright © 1997-1999 Vita Nuova Limited
|
|
// Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
|
|
// Portions Copyright © 2004,2006 Bruce Ellis
|
|
// Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
|
|
// Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
|
|
// Portions Copyright © 2009 The Go Authors. All rights reserved.
|
|
//
|
|
// Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
// of this software and associated documentation files (the "Software"), to deal
|
|
// in the Software without restriction, including without limitation the rights
|
|
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
// copies of the Software, and to permit persons to whom the Software is
|
|
// furnished to do so, subject to the following conditions:
|
|
//
|
|
// The above copyright notice and this permission notice shall be included in
|
|
// all copies or substantial portions of the Software.
|
|
//
|
|
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
|
// THE SOFTWARE.
|
|
|
|
package arm64
|
|
|
|
import (
|
|
"fmt"
|
|
"log"
|
|
"math"
|
|
|
|
"github.com/google/gops/internal/obj"
|
|
"github.com/google/gops/internal/sys"
|
|
)
|
|
|
|
var complements = []obj.As{
|
|
AADD: ASUB,
|
|
AADDW: ASUBW,
|
|
ASUB: AADD,
|
|
ASUBW: AADDW,
|
|
ACMP: ACMN,
|
|
ACMPW: ACMNW,
|
|
ACMN: ACMP,
|
|
ACMNW: ACMPW,
|
|
}
|
|
|
|
func stacksplit(ctxt *obj.Link, p *obj.Prog, framesize int32) *obj.Prog {
|
|
// MOV g_stackguard(g), R1
|
|
p = obj.Appendp(ctxt, p)
|
|
|
|
p.As = AMOVD
|
|
p.From.Type = obj.TYPE_MEM
|
|
p.From.Reg = REGG
|
|
p.From.Offset = 2 * int64(ctxt.Arch.PtrSize) // G.stackguard0
|
|
if ctxt.Cursym.CFunc() {
|
|
p.From.Offset = 3 * int64(ctxt.Arch.PtrSize) // G.stackguard1
|
|
}
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REG_R1
|
|
|
|
q := (*obj.Prog)(nil)
|
|
if framesize <= obj.StackSmall {
|
|
// small stack: SP < stackguard
|
|
// MOV SP, R2
|
|
// CMP stackguard, R2
|
|
p = obj.Appendp(ctxt, p)
|
|
|
|
p.As = AMOVD
|
|
p.From.Type = obj.TYPE_REG
|
|
p.From.Reg = REGSP
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REG_R2
|
|
|
|
p = obj.Appendp(ctxt, p)
|
|
p.As = ACMP
|
|
p.From.Type = obj.TYPE_REG
|
|
p.From.Reg = REG_R1
|
|
p.Reg = REG_R2
|
|
} else if framesize <= obj.StackBig {
|
|
// large stack: SP-framesize < stackguard-StackSmall
|
|
// SUB $framesize, SP, R2
|
|
// CMP stackguard, R2
|
|
p = obj.Appendp(ctxt, p)
|
|
|
|
p.As = ASUB
|
|
p.From.Type = obj.TYPE_CONST
|
|
p.From.Offset = int64(framesize)
|
|
p.Reg = REGSP
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REG_R2
|
|
|
|
p = obj.Appendp(ctxt, p)
|
|
p.As = ACMP
|
|
p.From.Type = obj.TYPE_REG
|
|
p.From.Reg = REG_R1
|
|
p.Reg = REG_R2
|
|
} else {
|
|
// Such a large stack we need to protect against wraparound
|
|
// if SP is close to zero.
|
|
// SP-stackguard+StackGuard < framesize + (StackGuard-StackSmall)
|
|
// The +StackGuard on both sides is required to keep the left side positive:
|
|
// SP is allowed to be slightly below stackguard. See stack.h.
|
|
// CMP $StackPreempt, R1
|
|
// BEQ label_of_call_to_morestack
|
|
// ADD $StackGuard, SP, R2
|
|
// SUB R1, R2
|
|
// MOV $(framesize+(StackGuard-StackSmall)), R3
|
|
// CMP R3, R2
|
|
p = obj.Appendp(ctxt, p)
|
|
|
|
p.As = ACMP
|
|
p.From.Type = obj.TYPE_CONST
|
|
p.From.Offset = obj.StackPreempt
|
|
p.Reg = REG_R1
|
|
|
|
p = obj.Appendp(ctxt, p)
|
|
q = p
|
|
p.As = ABEQ
|
|
p.To.Type = obj.TYPE_BRANCH
|
|
|
|
p = obj.Appendp(ctxt, p)
|
|
p.As = AADD
|
|
p.From.Type = obj.TYPE_CONST
|
|
p.From.Offset = obj.StackGuard
|
|
p.Reg = REGSP
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REG_R2
|
|
|
|
p = obj.Appendp(ctxt, p)
|
|
p.As = ASUB
|
|
p.From.Type = obj.TYPE_REG
|
|
p.From.Reg = REG_R1
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REG_R2
|
|
|
|
p = obj.Appendp(ctxt, p)
|
|
p.As = AMOVD
|
|
p.From.Type = obj.TYPE_CONST
|
|
p.From.Offset = int64(framesize) + (obj.StackGuard - obj.StackSmall)
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REG_R3
|
|
|
|
p = obj.Appendp(ctxt, p)
|
|
p.As = ACMP
|
|
p.From.Type = obj.TYPE_REG
|
|
p.From.Reg = REG_R3
|
|
p.Reg = REG_R2
|
|
}
|
|
|
|
// BLS do-morestack
|
|
bls := obj.Appendp(ctxt, p)
|
|
bls.As = ABLS
|
|
bls.To.Type = obj.TYPE_BRANCH
|
|
|
|
var last *obj.Prog
|
|
for last = ctxt.Cursym.Text; last.Link != nil; last = last.Link {
|
|
}
|
|
|
|
// Now we are at the end of the function, but logically
|
|
// we are still in function prologue. We need to fix the
|
|
// SP data and PCDATA.
|
|
spfix := obj.Appendp(ctxt, last)
|
|
spfix.As = obj.ANOP
|
|
spfix.Spadj = -framesize
|
|
|
|
pcdata := obj.Appendp(ctxt, spfix)
|
|
pcdata.Lineno = ctxt.Cursym.Text.Lineno
|
|
pcdata.Mode = ctxt.Cursym.Text.Mode
|
|
pcdata.As = obj.APCDATA
|
|
pcdata.From.Type = obj.TYPE_CONST
|
|
pcdata.From.Offset = obj.PCDATA_StackMapIndex
|
|
pcdata.To.Type = obj.TYPE_CONST
|
|
pcdata.To.Offset = -1 // pcdata starts at -1 at function entry
|
|
|
|
// MOV LR, R3
|
|
movlr := obj.Appendp(ctxt, pcdata)
|
|
movlr.As = AMOVD
|
|
movlr.From.Type = obj.TYPE_REG
|
|
movlr.From.Reg = REGLINK
|
|
movlr.To.Type = obj.TYPE_REG
|
|
movlr.To.Reg = REG_R3
|
|
if q != nil {
|
|
q.Pcond = movlr
|
|
}
|
|
bls.Pcond = movlr
|
|
|
|
debug := movlr
|
|
if false {
|
|
debug = obj.Appendp(ctxt, debug)
|
|
debug.As = AMOVD
|
|
debug.From.Type = obj.TYPE_CONST
|
|
debug.From.Offset = int64(framesize)
|
|
debug.To.Type = obj.TYPE_REG
|
|
debug.To.Reg = REGTMP
|
|
}
|
|
|
|
// BL runtime.morestack(SB)
|
|
call := obj.Appendp(ctxt, debug)
|
|
call.As = ABL
|
|
call.To.Type = obj.TYPE_BRANCH
|
|
morestack := "runtime.morestack"
|
|
switch {
|
|
case ctxt.Cursym.CFunc():
|
|
morestack = "runtime.morestackc"
|
|
case ctxt.Cursym.Text.From3.Offset&obj.NEEDCTXT == 0:
|
|
morestack = "runtime.morestack_noctxt"
|
|
}
|
|
call.To.Sym = obj.Linklookup(ctxt, morestack, 0)
|
|
|
|
// B start
|
|
jmp := obj.Appendp(ctxt, call)
|
|
jmp.As = AB
|
|
jmp.To.Type = obj.TYPE_BRANCH
|
|
jmp.Pcond = ctxt.Cursym.Text.Link
|
|
jmp.Spadj = +framesize
|
|
|
|
// placeholder for bls's jump target
|
|
// p = obj.Appendp(ctxt, p)
|
|
// p.As = obj.ANOP
|
|
|
|
return bls
|
|
}
|
|
|
|
func progedit(ctxt *obj.Link, p *obj.Prog) {
|
|
p.From.Class = 0
|
|
p.To.Class = 0
|
|
|
|
// $0 results in C_ZCON, which matches both C_REG and various
|
|
// C_xCON, however the C_REG cases in asmout don't expect a
|
|
// constant, so they will use the register fields and assemble
|
|
// a R0. To prevent that, rewrite $0 as ZR.
|
|
if p.From.Type == obj.TYPE_CONST && p.From.Offset == 0 {
|
|
p.From.Type = obj.TYPE_REG
|
|
p.From.Reg = REGZERO
|
|
}
|
|
if p.To.Type == obj.TYPE_CONST && p.To.Offset == 0 {
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REGZERO
|
|
}
|
|
|
|
// Rewrite BR/BL to symbol as TYPE_BRANCH.
|
|
switch p.As {
|
|
case AB,
|
|
ABL,
|
|
obj.ARET,
|
|
obj.ADUFFZERO,
|
|
obj.ADUFFCOPY:
|
|
if p.To.Sym != nil {
|
|
p.To.Type = obj.TYPE_BRANCH
|
|
}
|
|
break
|
|
}
|
|
|
|
// Rewrite float constants to values stored in memory.
|
|
switch p.As {
|
|
case AFMOVS:
|
|
if p.From.Type == obj.TYPE_FCONST {
|
|
f32 := float32(p.From.Val.(float64))
|
|
i32 := math.Float32bits(f32)
|
|
if i32 == 0 {
|
|
p.From.Type = obj.TYPE_REG
|
|
p.From.Reg = REGZERO
|
|
break
|
|
}
|
|
literal := fmt.Sprintf("$f32.%08x", i32)
|
|
s := obj.Linklookup(ctxt, literal, 0)
|
|
s.Size = 4
|
|
p.From.Type = obj.TYPE_MEM
|
|
p.From.Sym = s
|
|
p.From.Sym.Set(obj.AttrLocal, true)
|
|
p.From.Name = obj.NAME_EXTERN
|
|
p.From.Offset = 0
|
|
}
|
|
|
|
case AFMOVD:
|
|
if p.From.Type == obj.TYPE_FCONST {
|
|
i64 := math.Float64bits(p.From.Val.(float64))
|
|
if i64 == 0 {
|
|
p.From.Type = obj.TYPE_REG
|
|
p.From.Reg = REGZERO
|
|
break
|
|
}
|
|
literal := fmt.Sprintf("$f64.%016x", i64)
|
|
s := obj.Linklookup(ctxt, literal, 0)
|
|
s.Size = 8
|
|
p.From.Type = obj.TYPE_MEM
|
|
p.From.Sym = s
|
|
p.From.Sym.Set(obj.AttrLocal, true)
|
|
p.From.Name = obj.NAME_EXTERN
|
|
p.From.Offset = 0
|
|
}
|
|
|
|
break
|
|
}
|
|
|
|
// Rewrite negative immediates as positive immediates with
|
|
// complementary instruction.
|
|
switch p.As {
|
|
case AADD, ASUB, ACMP, ACMN:
|
|
if p.From.Type == obj.TYPE_CONST && p.From.Offset < 0 && p.From.Offset != -1<<63 {
|
|
p.From.Offset = -p.From.Offset
|
|
p.As = complements[p.As]
|
|
}
|
|
case AADDW, ASUBW, ACMPW, ACMNW:
|
|
if p.From.Type == obj.TYPE_CONST && p.From.Offset < 0 && int32(p.From.Offset) != -1<<31 {
|
|
p.From.Offset = -p.From.Offset
|
|
p.As = complements[p.As]
|
|
}
|
|
}
|
|
|
|
// For 32-bit logical instruction with constant,
|
|
// rewrite the high 32-bit to be a repetition of
|
|
// the low 32-bit, so that the BITCON test can be
|
|
// shared for both 32-bit and 64-bit. 32-bit ops
|
|
// will zero the high 32-bit of the destination
|
|
// register anyway.
|
|
switch p.As {
|
|
case AANDW, AORRW, AEORW, AANDSW:
|
|
if p.From.Type == obj.TYPE_CONST {
|
|
v := p.From.Offset & 0xffffffff
|
|
p.From.Offset = v | v<<32
|
|
}
|
|
}
|
|
|
|
if ctxt.Flag_dynlink {
|
|
rewriteToUseGot(ctxt, p)
|
|
}
|
|
}
|
|
|
|
// Rewrite p, if necessary, to access global data via the global offset table.
|
|
func rewriteToUseGot(ctxt *obj.Link, p *obj.Prog) {
|
|
if p.As == obj.ADUFFCOPY || p.As == obj.ADUFFZERO {
|
|
// ADUFFxxx $offset
|
|
// becomes
|
|
// MOVD runtime.duffxxx@GOT, REGTMP
|
|
// ADD $offset, REGTMP
|
|
// CALL REGTMP
|
|
var sym *obj.LSym
|
|
if p.As == obj.ADUFFZERO {
|
|
sym = obj.Linklookup(ctxt, "runtime.duffzero", 0)
|
|
} else {
|
|
sym = obj.Linklookup(ctxt, "runtime.duffcopy", 0)
|
|
}
|
|
offset := p.To.Offset
|
|
p.As = AMOVD
|
|
p.From.Type = obj.TYPE_MEM
|
|
p.From.Name = obj.NAME_GOTREF
|
|
p.From.Sym = sym
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REGTMP
|
|
p.To.Name = obj.NAME_NONE
|
|
p.To.Offset = 0
|
|
p.To.Sym = nil
|
|
p1 := obj.Appendp(ctxt, p)
|
|
p1.As = AADD
|
|
p1.From.Type = obj.TYPE_CONST
|
|
p1.From.Offset = offset
|
|
p1.To.Type = obj.TYPE_REG
|
|
p1.To.Reg = REGTMP
|
|
p2 := obj.Appendp(ctxt, p1)
|
|
p2.As = obj.ACALL
|
|
p2.To.Type = obj.TYPE_REG
|
|
p2.To.Reg = REGTMP
|
|
}
|
|
|
|
// We only care about global data: NAME_EXTERN means a global
|
|
// symbol in the Go sense, and p.Sym.Local is true for a few
|
|
// internally defined symbols.
|
|
if p.From.Type == obj.TYPE_ADDR && p.From.Name == obj.NAME_EXTERN && !p.From.Sym.Local() {
|
|
// MOVD $sym, Rx becomes MOVD sym@GOT, Rx
|
|
// MOVD $sym+<off>, Rx becomes MOVD sym@GOT, Rx; ADD <off>, Rx
|
|
if p.As != AMOVD {
|
|
ctxt.Diag("do not know how to handle TYPE_ADDR in %v with -dynlink", p)
|
|
}
|
|
if p.To.Type != obj.TYPE_REG {
|
|
ctxt.Diag("do not know how to handle LEAQ-type insn to non-register in %v with -dynlink", p)
|
|
}
|
|
p.From.Type = obj.TYPE_MEM
|
|
p.From.Name = obj.NAME_GOTREF
|
|
if p.From.Offset != 0 {
|
|
q := obj.Appendp(ctxt, p)
|
|
q.As = AADD
|
|
q.From.Type = obj.TYPE_CONST
|
|
q.From.Offset = p.From.Offset
|
|
q.To = p.To
|
|
p.From.Offset = 0
|
|
}
|
|
}
|
|
if p.From3 != nil && p.From3.Name == obj.NAME_EXTERN {
|
|
ctxt.Diag("don't know how to handle %v with -dynlink", p)
|
|
}
|
|
var source *obj.Addr
|
|
// MOVx sym, Ry becomes MOVD sym@GOT, REGTMP; MOVx (REGTMP), Ry
|
|
// MOVx Ry, sym becomes MOVD sym@GOT, REGTMP; MOVD Ry, (REGTMP)
|
|
// An addition may be inserted between the two MOVs if there is an offset.
|
|
if p.From.Name == obj.NAME_EXTERN && !p.From.Sym.Local() {
|
|
if p.To.Name == obj.NAME_EXTERN && !p.To.Sym.Local() {
|
|
ctxt.Diag("cannot handle NAME_EXTERN on both sides in %v with -dynlink", p)
|
|
}
|
|
source = &p.From
|
|
} else if p.To.Name == obj.NAME_EXTERN && !p.To.Sym.Local() {
|
|
source = &p.To
|
|
} else {
|
|
return
|
|
}
|
|
if p.As == obj.ATEXT || p.As == obj.AFUNCDATA || p.As == obj.ACALL || p.As == obj.ARET || p.As == obj.AJMP {
|
|
return
|
|
}
|
|
if source.Sym.Type == obj.STLSBSS {
|
|
return
|
|
}
|
|
if source.Type != obj.TYPE_MEM {
|
|
ctxt.Diag("don't know how to handle %v with -dynlink", p)
|
|
}
|
|
p1 := obj.Appendp(ctxt, p)
|
|
p2 := obj.Appendp(ctxt, p1)
|
|
p1.As = AMOVD
|
|
p1.From.Type = obj.TYPE_MEM
|
|
p1.From.Sym = source.Sym
|
|
p1.From.Name = obj.NAME_GOTREF
|
|
p1.To.Type = obj.TYPE_REG
|
|
p1.To.Reg = REGTMP
|
|
|
|
p2.As = p.As
|
|
p2.From = p.From
|
|
p2.To = p.To
|
|
if p.From.Name == obj.NAME_EXTERN {
|
|
p2.From.Reg = REGTMP
|
|
p2.From.Name = obj.NAME_NONE
|
|
p2.From.Sym = nil
|
|
} else if p.To.Name == obj.NAME_EXTERN {
|
|
p2.To.Reg = REGTMP
|
|
p2.To.Name = obj.NAME_NONE
|
|
p2.To.Sym = nil
|
|
} else {
|
|
return
|
|
}
|
|
obj.Nopout(p)
|
|
}
|
|
|
|
func follow(ctxt *obj.Link, s *obj.LSym) {
|
|
ctxt.Cursym = s
|
|
|
|
firstp := ctxt.NewProg()
|
|
lastp := firstp
|
|
xfol(ctxt, s.Text, &lastp)
|
|
lastp.Link = nil
|
|
s.Text = firstp.Link
|
|
}
|
|
|
|
func relinv(a obj.As) obj.As {
|
|
switch a {
|
|
case ABEQ:
|
|
return ABNE
|
|
case ABNE:
|
|
return ABEQ
|
|
case ABCS:
|
|
return ABCC
|
|
case ABHS:
|
|
return ABLO
|
|
case ABCC:
|
|
return ABCS
|
|
case ABLO:
|
|
return ABHS
|
|
case ABMI:
|
|
return ABPL
|
|
case ABPL:
|
|
return ABMI
|
|
case ABVS:
|
|
return ABVC
|
|
case ABVC:
|
|
return ABVS
|
|
case ABHI:
|
|
return ABLS
|
|
case ABLS:
|
|
return ABHI
|
|
case ABGE:
|
|
return ABLT
|
|
case ABLT:
|
|
return ABGE
|
|
case ABGT:
|
|
return ABLE
|
|
case ABLE:
|
|
return ABGT
|
|
case ACBZ:
|
|
return ACBNZ
|
|
case ACBNZ:
|
|
return ACBZ
|
|
case ACBZW:
|
|
return ACBNZW
|
|
case ACBNZW:
|
|
return ACBZW
|
|
}
|
|
|
|
log.Fatalf("unknown relation: %s", Anames[a-obj.ABaseARM64])
|
|
return 0
|
|
}
|
|
|
|
func xfol(ctxt *obj.Link, p *obj.Prog, last **obj.Prog) {
|
|
var q *obj.Prog
|
|
var r *obj.Prog
|
|
var i int
|
|
|
|
loop:
|
|
if p == nil {
|
|
return
|
|
}
|
|
a := p.As
|
|
if a == AB {
|
|
q = p.Pcond
|
|
if q != nil {
|
|
p.Mark |= FOLL
|
|
p = q
|
|
if !(p.Mark&FOLL != 0) {
|
|
goto loop
|
|
}
|
|
}
|
|
}
|
|
|
|
if p.Mark&FOLL != 0 {
|
|
i = 0
|
|
q = p
|
|
for ; i < 4; i, q = i+1, q.Link {
|
|
if q == *last || q == nil {
|
|
break
|
|
}
|
|
a = q.As
|
|
if a == obj.ANOP {
|
|
i--
|
|
continue
|
|
}
|
|
|
|
if a == AB || a == obj.ARET || a == AERET {
|
|
goto copy
|
|
}
|
|
if q.Pcond == nil || (q.Pcond.Mark&FOLL != 0) {
|
|
continue
|
|
}
|
|
if a != ABEQ && a != ABNE {
|
|
continue
|
|
}
|
|
|
|
copy:
|
|
for {
|
|
r = ctxt.NewProg()
|
|
*r = *p
|
|
if !(r.Mark&FOLL != 0) {
|
|
fmt.Printf("can't happen 1\n")
|
|
}
|
|
r.Mark |= FOLL
|
|
if p != q {
|
|
p = p.Link
|
|
(*last).Link = r
|
|
*last = r
|
|
continue
|
|
}
|
|
|
|
(*last).Link = r
|
|
*last = r
|
|
if a == AB || a == obj.ARET || a == AERET {
|
|
return
|
|
}
|
|
if a == ABNE {
|
|
r.As = ABEQ
|
|
} else {
|
|
r.As = ABNE
|
|
}
|
|
r.Pcond = p.Link
|
|
r.Link = p.Pcond
|
|
if !(r.Link.Mark&FOLL != 0) {
|
|
xfol(ctxt, r.Link, last)
|
|
}
|
|
if !(r.Pcond.Mark&FOLL != 0) {
|
|
fmt.Printf("can't happen 2\n")
|
|
}
|
|
return
|
|
}
|
|
}
|
|
|
|
a = AB
|
|
q = ctxt.NewProg()
|
|
q.As = a
|
|
q.Lineno = p.Lineno
|
|
q.To.Type = obj.TYPE_BRANCH
|
|
q.To.Offset = p.Pc
|
|
q.Pcond = p
|
|
p = q
|
|
}
|
|
|
|
p.Mark |= FOLL
|
|
(*last).Link = p
|
|
*last = p
|
|
if a == AB || a == obj.ARET || a == AERET {
|
|
return
|
|
}
|
|
if p.Pcond != nil {
|
|
if a != ABL && p.Link != nil {
|
|
q = obj.Brchain(ctxt, p.Link)
|
|
if a != obj.ATEXT {
|
|
if q != nil && (q.Mark&FOLL != 0) {
|
|
p.As = relinv(a)
|
|
p.Link = p.Pcond
|
|
p.Pcond = q
|
|
}
|
|
}
|
|
|
|
xfol(ctxt, p.Link, last)
|
|
q = obj.Brchain(ctxt, p.Pcond)
|
|
if q == nil {
|
|
q = p.Pcond
|
|
}
|
|
if q.Mark&FOLL != 0 {
|
|
p.Pcond = q
|
|
return
|
|
}
|
|
|
|
p = q
|
|
goto loop
|
|
}
|
|
}
|
|
|
|
p = p.Link
|
|
goto loop
|
|
}
|
|
|
|
func preprocess(ctxt *obj.Link, cursym *obj.LSym) {
|
|
ctxt.Cursym = cursym
|
|
|
|
if cursym.Text == nil || cursym.Text.Link == nil {
|
|
return
|
|
}
|
|
|
|
p := cursym.Text
|
|
textstksiz := p.To.Offset
|
|
aoffset := int32(textstksiz)
|
|
|
|
cursym.Args = p.To.Val.(int32)
|
|
cursym.Locals = int32(textstksiz)
|
|
|
|
/*
|
|
* find leaf subroutines
|
|
* strip NOPs
|
|
* expand RET
|
|
*/
|
|
q := (*obj.Prog)(nil)
|
|
var q1 *obj.Prog
|
|
for p := cursym.Text; p != nil; p = p.Link {
|
|
switch p.As {
|
|
case obj.ATEXT:
|
|
p.Mark |= LEAF
|
|
|
|
case obj.ARET:
|
|
break
|
|
|
|
case obj.ANOP:
|
|
q1 = p.Link
|
|
q.Link = q1 /* q is non-nop */
|
|
q1.Mark |= p.Mark
|
|
continue
|
|
|
|
case ABL,
|
|
obj.ADUFFZERO,
|
|
obj.ADUFFCOPY:
|
|
cursym.Text.Mark &^= LEAF
|
|
fallthrough
|
|
|
|
case ACBNZ,
|
|
ACBZ,
|
|
ACBNZW,
|
|
ACBZW,
|
|
ATBZ,
|
|
ATBNZ,
|
|
AB,
|
|
ABEQ,
|
|
ABNE,
|
|
ABCS,
|
|
ABHS,
|
|
ABCC,
|
|
ABLO,
|
|
ABMI,
|
|
ABPL,
|
|
ABVS,
|
|
ABVC,
|
|
ABHI,
|
|
ABLS,
|
|
ABGE,
|
|
ABLT,
|
|
ABGT,
|
|
ABLE,
|
|
AADR, /* strange */
|
|
AADRP:
|
|
q1 = p.Pcond
|
|
|
|
if q1 != nil {
|
|
for q1.As == obj.ANOP {
|
|
q1 = q1.Link
|
|
p.Pcond = q1
|
|
}
|
|
}
|
|
|
|
break
|
|
}
|
|
|
|
q = p
|
|
}
|
|
|
|
var q2 *obj.Prog
|
|
var retjmp *obj.LSym
|
|
for p := cursym.Text; p != nil; p = p.Link {
|
|
o := p.As
|
|
switch o {
|
|
case obj.ATEXT:
|
|
cursym.Text = p
|
|
if textstksiz < 0 {
|
|
ctxt.Autosize = 0
|
|
} else {
|
|
ctxt.Autosize = int32(textstksiz + 8)
|
|
}
|
|
if (cursym.Text.Mark&LEAF != 0) && ctxt.Autosize <= 8 {
|
|
ctxt.Autosize = 0
|
|
} else if ctxt.Autosize&(16-1) != 0 {
|
|
// The frame includes an LR.
|
|
// If the frame size is 8, it's only an LR,
|
|
// so there's no potential for breaking references to
|
|
// local variables by growing the frame size,
|
|
// because there are no local variables.
|
|
// But otherwise, if there is a non-empty locals section,
|
|
// the author of the code is responsible for making sure
|
|
// that the frame size is 8 mod 16.
|
|
if ctxt.Autosize == 8 {
|
|
ctxt.Autosize += 8
|
|
cursym.Locals += 8
|
|
} else {
|
|
ctxt.Diag("%v: unaligned frame size %d - must be 8 mod 16 (or 0)", p, ctxt.Autosize-8)
|
|
}
|
|
}
|
|
p.To.Offset = int64(ctxt.Autosize) - 8
|
|
if ctxt.Autosize == 0 && !(cursym.Text.Mark&LEAF != 0) {
|
|
if ctxt.Debugvlog != 0 {
|
|
ctxt.Logf("save suppressed in: %s\n", cursym.Text.From.Sym.Name)
|
|
}
|
|
cursym.Text.Mark |= LEAF
|
|
}
|
|
|
|
if !(p.From3.Offset&obj.NOSPLIT != 0) {
|
|
p = stacksplit(ctxt, p, ctxt.Autosize) // emit split check
|
|
}
|
|
|
|
aoffset = ctxt.Autosize
|
|
if aoffset > 0xF0 {
|
|
aoffset = 0xF0
|
|
}
|
|
if cursym.Text.Mark&LEAF != 0 {
|
|
cursym.Set(obj.AttrLeaf, true)
|
|
if ctxt.Autosize == 0 {
|
|
break
|
|
}
|
|
}
|
|
|
|
// Frame is non-empty. Make sure to save link register, even if
|
|
// it is a leaf function, so that traceback works.
|
|
q = p
|
|
if ctxt.Autosize > aoffset {
|
|
// Frame size is too large for a MOVD.W instruction.
|
|
// Store link register before decrementing SP, so if a signal comes
|
|
// during the execution of the function prologue, the traceback
|
|
// code will not see a half-updated stack frame.
|
|
q = obj.Appendp(ctxt, q)
|
|
q.Lineno = p.Lineno
|
|
q.As = ASUB
|
|
q.From.Type = obj.TYPE_CONST
|
|
q.From.Offset = int64(ctxt.Autosize)
|
|
q.Reg = REGSP
|
|
q.To.Type = obj.TYPE_REG
|
|
q.To.Reg = REGTMP
|
|
|
|
q = obj.Appendp(ctxt, q)
|
|
q.Lineno = p.Lineno
|
|
q.As = AMOVD
|
|
q.From.Type = obj.TYPE_REG
|
|
q.From.Reg = REGLINK
|
|
q.To.Type = obj.TYPE_MEM
|
|
q.To.Reg = REGTMP
|
|
|
|
q1 = obj.Appendp(ctxt, q)
|
|
q1.Lineno = p.Lineno
|
|
q1.As = AMOVD
|
|
q1.From.Type = obj.TYPE_REG
|
|
q1.From.Reg = REGTMP
|
|
q1.To.Type = obj.TYPE_REG
|
|
q1.To.Reg = REGSP
|
|
q1.Spadj = ctxt.Autosize
|
|
} else {
|
|
// small frame, update SP and save LR in a single MOVD.W instruction
|
|
q1 = obj.Appendp(ctxt, q)
|
|
q1.As = AMOVD
|
|
q1.Lineno = p.Lineno
|
|
q1.From.Type = obj.TYPE_REG
|
|
q1.From.Reg = REGLINK
|
|
q1.To.Type = obj.TYPE_MEM
|
|
q1.Scond = C_XPRE
|
|
q1.To.Offset = int64(-aoffset)
|
|
q1.To.Reg = REGSP
|
|
q1.Spadj = aoffset
|
|
}
|
|
|
|
if cursym.Text.From3.Offset&obj.WRAPPER != 0 {
|
|
// if(g->panic != nil && g->panic->argp == FP) g->panic->argp = bottom-of-frame
|
|
//
|
|
// MOV g_panic(g), R1
|
|
// CMP ZR, R1
|
|
// BEQ end
|
|
// MOV panic_argp(R1), R2
|
|
// ADD $(autosize+8), RSP, R3
|
|
// CMP R2, R3
|
|
// BNE end
|
|
// ADD $8, RSP, R4
|
|
// MOVD R4, panic_argp(R1)
|
|
// end:
|
|
// NOP
|
|
//
|
|
// The NOP is needed to give the jumps somewhere to land.
|
|
// It is a liblink NOP, not a ARM64 NOP: it encodes to 0 instruction bytes.
|
|
q = q1
|
|
|
|
q = obj.Appendp(ctxt, q)
|
|
q.As = AMOVD
|
|
q.From.Type = obj.TYPE_MEM
|
|
q.From.Reg = REGG
|
|
q.From.Offset = 4 * int64(ctxt.Arch.PtrSize) // G.panic
|
|
q.To.Type = obj.TYPE_REG
|
|
q.To.Reg = REG_R1
|
|
|
|
q = obj.Appendp(ctxt, q)
|
|
q.As = ACMP
|
|
q.From.Type = obj.TYPE_REG
|
|
q.From.Reg = REGZERO
|
|
q.Reg = REG_R1
|
|
|
|
q = obj.Appendp(ctxt, q)
|
|
q.As = ABEQ
|
|
q.To.Type = obj.TYPE_BRANCH
|
|
q1 = q
|
|
|
|
q = obj.Appendp(ctxt, q)
|
|
q.As = AMOVD
|
|
q.From.Type = obj.TYPE_MEM
|
|
q.From.Reg = REG_R1
|
|
q.From.Offset = 0 // Panic.argp
|
|
q.To.Type = obj.TYPE_REG
|
|
q.To.Reg = REG_R2
|
|
|
|
q = obj.Appendp(ctxt, q)
|
|
q.As = AADD
|
|
q.From.Type = obj.TYPE_CONST
|
|
q.From.Offset = int64(ctxt.Autosize) + 8
|
|
q.Reg = REGSP
|
|
q.To.Type = obj.TYPE_REG
|
|
q.To.Reg = REG_R3
|
|
|
|
q = obj.Appendp(ctxt, q)
|
|
q.As = ACMP
|
|
q.From.Type = obj.TYPE_REG
|
|
q.From.Reg = REG_R2
|
|
q.Reg = REG_R3
|
|
|
|
q = obj.Appendp(ctxt, q)
|
|
q.As = ABNE
|
|
q.To.Type = obj.TYPE_BRANCH
|
|
q2 = q
|
|
|
|
q = obj.Appendp(ctxt, q)
|
|
q.As = AADD
|
|
q.From.Type = obj.TYPE_CONST
|
|
q.From.Offset = 8
|
|
q.Reg = REGSP
|
|
q.To.Type = obj.TYPE_REG
|
|
q.To.Reg = REG_R4
|
|
|
|
q = obj.Appendp(ctxt, q)
|
|
q.As = AMOVD
|
|
q.From.Type = obj.TYPE_REG
|
|
q.From.Reg = REG_R4
|
|
q.To.Type = obj.TYPE_MEM
|
|
q.To.Reg = REG_R1
|
|
q.To.Offset = 0 // Panic.argp
|
|
|
|
q = obj.Appendp(ctxt, q)
|
|
|
|
q.As = obj.ANOP
|
|
q1.Pcond = q
|
|
q2.Pcond = q
|
|
}
|
|
|
|
case obj.ARET:
|
|
nocache(p)
|
|
if p.From.Type == obj.TYPE_CONST {
|
|
ctxt.Diag("using BECOME (%v) is not supported!", p)
|
|
break
|
|
}
|
|
|
|
retjmp = p.To.Sym
|
|
p.To = obj.Addr{}
|
|
if cursym.Text.Mark&LEAF != 0 {
|
|
if ctxt.Autosize != 0 {
|
|
p.As = AADD
|
|
p.From.Type = obj.TYPE_CONST
|
|
p.From.Offset = int64(ctxt.Autosize)
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REGSP
|
|
p.Spadj = -ctxt.Autosize
|
|
}
|
|
} else {
|
|
/* want write-back pre-indexed SP+autosize -> SP, loading REGLINK*/
|
|
aoffset = ctxt.Autosize
|
|
|
|
if aoffset > 0xF0 {
|
|
aoffset = 0xF0
|
|
}
|
|
p.As = AMOVD
|
|
p.From.Type = obj.TYPE_MEM
|
|
p.Scond = C_XPOST
|
|
p.From.Offset = int64(aoffset)
|
|
p.From.Reg = REGSP
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REGLINK
|
|
p.Spadj = -aoffset
|
|
if ctxt.Autosize > aoffset {
|
|
q = ctxt.NewProg()
|
|
q.As = AADD
|
|
q.From.Type = obj.TYPE_CONST
|
|
q.From.Offset = int64(ctxt.Autosize) - int64(aoffset)
|
|
q.To.Type = obj.TYPE_REG
|
|
q.To.Reg = REGSP
|
|
q.Link = p.Link
|
|
q.Spadj = int32(-q.From.Offset)
|
|
q.Lineno = p.Lineno
|
|
p.Link = q
|
|
p = q
|
|
}
|
|
}
|
|
|
|
if p.As != obj.ARET {
|
|
q = ctxt.NewProg()
|
|
q.Lineno = p.Lineno
|
|
q.Link = p.Link
|
|
p.Link = q
|
|
p = q
|
|
}
|
|
|
|
if retjmp != nil { // retjmp
|
|
p.As = AB
|
|
p.To.Type = obj.TYPE_BRANCH
|
|
p.To.Sym = retjmp
|
|
p.Spadj = +ctxt.Autosize
|
|
break
|
|
}
|
|
|
|
p.As = obj.ARET
|
|
p.To.Type = obj.TYPE_MEM
|
|
p.To.Offset = 0
|
|
p.To.Reg = REGLINK
|
|
p.Spadj = +ctxt.Autosize
|
|
|
|
case AADD, ASUB:
|
|
if p.To.Type == obj.TYPE_REG && p.To.Reg == REGSP && p.From.Type == obj.TYPE_CONST {
|
|
if p.As == AADD {
|
|
p.Spadj = int32(-p.From.Offset)
|
|
} else {
|
|
p.Spadj = int32(+p.From.Offset)
|
|
}
|
|
}
|
|
break
|
|
}
|
|
}
|
|
}
|
|
|
|
func nocache(p *obj.Prog) {
|
|
p.Optab = 0
|
|
p.From.Class = 0
|
|
p.To.Class = 0
|
|
}
|
|
|
|
var unaryDst = map[obj.As]bool{
|
|
AWORD: true,
|
|
ADWORD: true,
|
|
ABL: true,
|
|
AB: true,
|
|
ASVC: true,
|
|
}
|
|
|
|
var Linkarm64 = obj.LinkArch{
|
|
Arch: sys.ArchARM64,
|
|
Preprocess: preprocess,
|
|
Assemble: span7,
|
|
Follow: follow,
|
|
Progedit: progedit,
|
|
UnaryDst: unaryDst,
|
|
}
|