作者：duhaibo040
项目：go-
func nacladdr(ctxt *obj.Link, p *obj.Prog, a *obj.Addr) {
if p.As == ALEAL || p.As == ALEAQ {
return
}
if a.Reg == REG_BP {
ctxt.Diag("invalid address: %v", p)
return
}
if a.Reg == REG_TLS {
a.Reg = REG_BP
}
if a.Type == obj.TYPE_MEM && a.Name == obj.NAME_NONE {
switch a.Reg {
// all ok
case REG_BP, REG_SP, REG_R15:
break
default:
if a.Index != REG_NONE {
ctxt.Diag("invalid address %v", p)
}
a.Index = a.Reg
if a.Index != REG_NONE {
a.Scale = 1
}
a.Reg = REG_R15
}
}
}
作者：arnold
项目：g
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
}
作者：arnold
项目：g
func initdiv(ctxt *obj.Link) {
if ctxt.Sym_div != nil {
return
}
ctxt.Sym_div = obj.Linklookup(ctxt, "_div", 0)
ctxt.Sym_divu = obj.Linklookup(ctxt, "_divu", 0)
ctxt.Sym_mod = obj.Linklookup(ctxt, "_mod", 0)
ctxt.Sym_modu = obj.Linklookup(ctxt, "_modu", 0)
}
作者：danny800
项目：g
func oplook(ctxt *obj.Link, p *obj.Prog) *Optab {
if oprange[AOR&obj.AMask].start == nil {
buildop(ctxt)
}
a1 := int(p.Optab)
if a1 != 0 {
return &optab[a1-1:][0]
}
a1 = int(p.From.Class)
if a1 == 0 {
a1 = aclass(ctxt, &p.From) + 1
p.From.Class = int8(a1)
}
a1--
a3 := int(p.To.Class)
if a3 == 0 {
a3 = aclass(ctxt, &p.To) + 1
p.To.Class = int8(a3)
}
a3--
a2 := C_NONE
if p.Reg != 0 {
a2 = C_REG
}
//print("oplook %P %d %d %d\n", p, a1, a2, a3);
r0 := p.As & obj.AMask
o := oprange[r0].start
if o == nil {
o = oprange[r0].stop /* just generate an error */
}
e := oprange[r0].stop
c1 := xcmp[a1][:]
c3 := xcmp[a3][:]
for ; -cap(o) < -cap(e); o = o[1:] {
if int(o[0].a2) == a2 {
if c1[o[0].a1] != 0 {
if c3[o[0].a3] != 0 {
p.Optab = uint16((-cap(o) + cap(optab)) + 1)
return &o[0]
}
}
}
}
ctxt.Diag("illegal combination %v %v %v %v", obj.Aconv(int(p.As)), DRconv(a1), DRconv(a2), DRconv(a3))
prasm(p)
if o == nil {
o = optab
}
return &o[0]
}
作者：Harvey-O
项目：g
func addnop(ctxt *obj.Link, p *obj.Prog) {
q := ctxt.NewProg()
// we want to use the canonical NOP (SLL $0,R0,R0) here,
// however, as the assembler will always replace $0
// as R0, we have to resort to manually encode the SLL
// instruction as WORD $0.
q.As = AWORD
q.Lineno = p.Lineno
q.From.Type = obj.TYPE_CONST
q.From.Name = obj.NAME_NONE
q.From.Offset = 0
q.Link = p.Link
p.Link = q
}
作者：2theto
项目：g
func oplook(ctxt *obj.Link, p *obj.Prog) *Optab {
if oprange[AOR&obj.AMask] == nil {
buildop(ctxt)
}
a1 := int(p.Optab)
if a1 != 0 {
return &optab[a1-1]
}
a1 = int(p.From.Class)
if a1 == 0 {
a1 = aclass(ctxt, &p.From) + 1
p.From.Class = int8(a1)
}
a1--
a3 := int(p.To.Class)
if a3 == 0 {
a3 = aclass(ctxt, &p.To) + 1
p.To.Class = int8(a3)
}
a3--
a2 := C_NONE
if p.Reg != 0 {
a2 = C_REG
}
//print("oplook %P %d %d %d\n", p, a1, a2, a3);
ops := oprange[p.As&obj.AMask]
c1 := &xcmp[a1]
c3 := &xcmp[a3]
for i := range ops {
op := &ops[i]
if int(op.a2) == a2 && c1[op.a1] && c3[op.a3] {
p.Optab = uint16(cap(optab) - cap(ops) + i + 1)
return op
}
}
ctxt.Diag("illegal combination %v %v %v %v", obj.Aconv(p.As), DRconv(a1), DRconv(a2), DRconv(a3))
prasm(p)
if ops == nil {
ops = optab
}
return &ops[0]
}
作者：achand
项目：g
func preprocess(ctxt *obj.Link, cursym *obj.LSym) {
if ctxt.Headtype == obj.Hplan9 && ctxt.Plan9privates == nil {
ctxt.Plan9privates = obj.Linklookup(ctxt, "_privates", 0)
}
ctxt.Cursym = cursym
if cursym.Text == nil || cursym.Text.Link == nil {
return
}
p := cursym.Text
autoffset := int32(p.To.Offset)
if autoffset < 0 {
autoffset = 0
}
var bpsize int
if p.Mode == 64 && ctxt.Framepointer_enabled && autoffset > 0 && p.From3.Offset&obj.NOFRAME == 0 {
// Make room for to save a base pointer. If autoffset == 0,
// this might do something special like a tail jump to
// another function, so in that case we omit this.
bpsize = ctxt.Arch.PtrSize
autoffset += int32(bpsize)
p.To.Offset += int64(bpsize)
} else {
bpsize = 0
}
textarg := int64(p.To.Val.(int32))
cursym.Args = int32(textarg)
cursym.Locals = int32(p.To.Offset)
// TODO(rsc): Remove.
if p.Mode == 32 && cursym.Locals < 0 {
cursym.Locals = 0
}
// TODO(rsc): Remove 'p.Mode == 64 &&'.
if p.Mode == 64 && autoffset < obj.StackSmall && p.From3Offset()&obj.NOSPLIT == 0 {
leaf := true
LeafSearch:
for q := p; q != nil; q = q.Link {
switch q.As {
case obj.ACALL:
// Treat common runtime calls that take no arguments
// the same as duffcopy and duffzero.
if !isZeroArgRuntimeCall(q.To.Sym) {
leaf = false
break LeafSearch
}
fallthrough
case obj.ADUFFCOPY, obj.ADUFFZERO:
if autoffset >= obj.StackSmall-8 {
leaf = false
break LeafSearch
}
}
}
if leaf {
p.From3.Offset |= obj.NOSPLIT
}
}
if p.From3Offset()&obj.NOSPLIT == 0 || p.From3Offset()&obj.WRAPPER != 0 {
p = obj.Appendp(ctxt, p)
p = load_g_cx(ctxt, p) // load g into CX
}
if cursym.Text.From3Offset()&obj.NOSPLIT == 0 {
p = stacksplit(ctxt, p, autoffset, int32(textarg)) // emit split check
}
if autoffset != 0 {
if autoffset%int32(ctxt.Arch.RegSize) != 0 {
ctxt.Diag("unaligned stack size %d", autoffset)
}
p = obj.Appendp(ctxt, p)
p.As = AADJSP
p.From.Type = obj.TYPE_CONST
p.From.Offset = int64(autoffset)
p.Spadj = autoffset
}
deltasp := autoffset
if bpsize > 0 {
// Save caller's BP
p = obj.Appendp(ctxt, p)
p.As = AMOVQ
p.From.Type = obj.TYPE_REG
p.From.Reg = REG_BP
p.To.Type = obj.TYPE_MEM
p.To.Reg = REG_SP
p.To.Scale = 1
p.To.Offset = int64(autoffset) - int64(bpsize)
// Move current frame to BP
//.........这里部分代码省略.........
作者：duhaibo040
项目：go-
// Rewrite p, if necessary, to access global data via the global offset table.
func rewriteToUseGot(ctxt *obj.Link, p *obj.Prog) {
var add, lea, mov obj.As
var reg int16
if p.Mode == 64 {
add = AADDQ
lea = ALEAQ
mov = AMOVQ
reg = REG_R15
} else {
add = AADDL
lea = ALEAL
mov = AMOVL
reg = REG_CX
}
if p.As == obj.ADUFFCOPY || p.As == obj.ADUFFZERO {
// ADUFFxxx $offset
// becomes
// $MOV [email protected], $reg
// $ADD $offset, $reg
// CALL $reg
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 = mov
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 = reg
p.To.Offset = 0
p.To.Sym = nil
p1 := obj.Appendp(ctxt, p)
p1.As = add
p1.From.Type = obj.TYPE_CONST
p1.From.Offset = offset
p1.To.Type = obj.TYPE_REG
p1.To.Reg = reg
p2 := obj.Appendp(ctxt, p1)
p2.As = obj.ACALL
p2.To.Type = obj.TYPE_REG
p2.To.Reg = reg
}
// 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.As == lea && p.From.Type == obj.TYPE_MEM && p.From.Name == obj.NAME_EXTERN && !p.From.Sym.Local {
// $LEA sym, Rx becomes $MOV $sym, Rx which will be rewritten below
p.As = mov
p.From.Type = obj.TYPE_ADDR
}
if p.From.Type == obj.TYPE_ADDR && p.From.Name == obj.NAME_EXTERN && !p.From.Sym.Local {
// $MOV $sym, Rx becomes $MOV [email protected], Rx
// $MOV $sym+<off>, Rx becomes $MOV [email protected], Rx; $LEA <off>(Rx), Rx
// On 386 only, more complicated things like PUSHL $sym become $MOV [email protected], CX; PUSHL CX
cmplxdest := false
pAs := p.As
var dest obj.Addr
if p.To.Type != obj.TYPE_REG || pAs != mov {
if p.Mode == 64 {
ctxt.Diag("do not know how to handle LEA-type insn to non-register in %v with -dynlink", p)
}
cmplxdest = true
dest = p.To
p.As = mov
p.To.Type = obj.TYPE_REG
p.To.Reg = REG_CX
p.To.Sym = nil
p.To.Name = obj.NAME_NONE
}
p.From.Type = obj.TYPE_MEM
p.From.Name = obj.NAME_GOTREF
q := p
if p.From.Offset != 0 {
q = obj.Appendp(ctxt, p)
q.As = lea
q.From.Type = obj.TYPE_MEM
q.From.Reg = p.To.Reg
q.From.Offset = p.From.Offset
q.To = p.To
p.From.Offset = 0
}
if cmplxdest {
q = obj.Appendp(ctxt, q)
q.As = pAs
q.To = dest
q.From.Type = obj.TYPE_REG
q.From.Reg = REG_CX
}
}
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
//.........这里部分代码省略.........
作者：arnold
项目：g
func xfol(ctxt *obj.Link, p *obj.Prog, last **obj.Prog) {
var q *obj.Prog
var r *obj.Prog
var a int
var i int
loop:
if p == nil {
return
}
a = int(p.As)
if a == AB {
q = p.Pcond
if q != nil && q.As != obj.ATEXT {
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 = int(q.As)
if a == obj.ANOP {
i--
continue
}
if a == AB || (a == obj.ARET && q.Scond == C_SCOND_NONE) || a == ARFE || a == obj.AUNDEF {
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 && q.Scond == C_SCOND_NONE) || a == ARFE || a == obj.AUNDEF {
return
}
r.As = ABNE
if a == ABNE {
r.As = ABEQ
}
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 = int16(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 && p.Scond == C_SCOND_NONE) || a == ARFE || a == obj.AUNDEF {
return
}
if p.Pcond != nil {
if a != ABL && a != ABX && p.Link != nil {
//.........这里部分代码省略.........
作者：danny800
项目：g
func aclass(ctxt *obj.Link, a *obj.Addr) int {
switch a.Type {
case obj.TYPE_NONE:
return C_NONE
case obj.TYPE_REG:
if REG_R0 <= a.Reg && a.Reg <= REG_R31 {
return C_REG
}
if REG_F0 <= a.Reg && a.Reg <= REG_F31 {
return C_FREG
}
if REG_M0 <= a.Reg && a.Reg <= REG_M31 {
return C_MREG
}
if REG_FCR0 <= a.Reg && a.Reg <= REG_FCR31 {
return C_FCREG
}
if a.Reg == REG_LO {
return C_LO
}
if a.Reg == REG_HI {
return C_HI
}
return C_GOK
case obj.TYPE_MEM:
switch a.Name {
case obj.NAME_EXTERN,
obj.NAME_STATIC:
if a.Sym == nil {
break
}
ctxt.Instoffset = a.Offset
if a.Sym != nil { // use relocation
return C_ADDR
}
return C_LEXT
case obj.NAME_AUTO:
ctxt.Instoffset = int64(ctxt.Autosize) + a.Offset
if ctxt.Instoffset >= -BIG && ctxt.Instoffset < BIG {
return C_SAUTO
}
return C_LAUTO
case obj.NAME_PARAM:
ctxt.Instoffset = int64(ctxt.Autosize) + a.Offset + 8
if ctxt.Instoffset >= -BIG && ctxt.Instoffset < BIG {
return C_SAUTO
}
return C_LAUTO
case obj.NAME_NONE:
ctxt.Instoffset = a.Offset
if ctxt.Instoffset == 0 {
return C_ZOREG
}
if ctxt.Instoffset >= -BIG && ctxt.Instoffset < BIG {
return C_SOREG
}
return C_LOREG
}
return C_GOK
case obj.TYPE_TEXTSIZE:
return C_TEXTSIZE
case obj.TYPE_CONST,
obj.TYPE_ADDR:
switch a.Name {
case obj.NAME_NONE:
ctxt.Instoffset = a.Offset
if a.Reg != 0 {
if -BIG <= ctxt.Instoffset && ctxt.Instoffset <= BIG {
return C_SACON
}
if isint32(ctxt.Instoffset) {
return C_LACON
}
return C_DACON
}
goto consize
case obj.NAME_EXTERN,
obj.NAME_STATIC:
s := a.Sym
if s == nil {
break
}
if s.Type == obj.SCONST {
ctxt.Instoffset = s.Value + a.Offset
goto consize
}
ctxt.Instoffset = s.Value + a.Offset
/* not sure why this barfs */
//.........这里部分代码省略.........
作者：danny800
项目：g
func opirr(ctxt *obj.Link, a int) uint32 {
switch a {
case AADD:
return SP(1, 0)
case AADDU:
return SP(1, 1)
case ASGT:
return SP(1, 2)
case ASGTU:
return SP(1, 3)
case AAND:
return SP(1, 4)
case AOR:
return SP(1, 5)
case AXOR:
return SP(1, 6)
case ALAST:
return SP(1, 7) /* lui */
case ASLL:
return OP(0, 0)
case ASRL:
return OP(0, 2)
case ASRA:
return OP(0, 3)
case AADDV:
return SP(3, 0)
case AADDVU:
return SP(3, 1)
case AJMP:
return SP(0, 2)
case AJAL,
obj.ADUFFZERO,
obj.ADUFFCOPY:
return SP(0, 3)
case ABEQ:
return SP(0, 4)
case ABEQ + ALAST:
return SP(2, 4) /* likely */
case ABNE:
return SP(0, 5)
case ABNE + ALAST:
return SP(2, 5) /* likely */
case ABGEZ:
return SP(0, 1) | BCOND(0, 1)
case ABGEZ + ALAST:
return SP(0, 1) | BCOND(0, 3) /* likely */
case ABGEZAL:
return SP(0, 1) | BCOND(2, 1)
case ABGEZAL + ALAST:
return SP(0, 1) | BCOND(2, 3) /* likely */
case ABGTZ:
return SP(0, 7)
case ABGTZ + ALAST:
return SP(2, 7) /* likely */
case ABLEZ:
return SP(0, 6)
case ABLEZ + ALAST:
return SP(2, 6) /* likely */
case ABLTZ:
return SP(0, 1) | BCOND(0, 0)
case ABLTZ + ALAST:
return SP(0, 1) | BCOND(0, 2) /* likely */
case ABLTZAL:
return SP(0, 1) | BCOND(2, 0)
case ABLTZAL + ALAST:
return SP(0, 1) | BCOND(2, 2) /* likely */
case ABFPT:
return SP(2, 1) | (257 << 16)
case ABFPT + ALAST:
return SP(2, 1) | (259 << 16) /* likely */
case ABFPF:
return SP(2, 1) | (256 << 16)
case ABFPF + ALAST:
return SP(2, 1) | (258 << 16) /* likely */
case AMOVB,
AMOVBU:
return SP(5, 0)
case AMOVH,
AMOVHU:
return SP(5, 1)
case AMOVW,
AMOVWU:
return SP(5, 3)
case AMOVV:
return SP(7, 7)
case AMOVF:
return SP(7, 1)
case AMOVD:
return SP(7, 5)
case AMOVWL:
return SP(5, 2)
case AMOVWR:
return SP(5, 6)
case AMOVVL:
return SP(5, 4)
case AMOVVR:
return SP(5, 5)
//.........这里部分代码省略.........
作者：danny800
项目：g
func vregoff(ctxt *obj.Link, a *obj.Addr) int64 {
ctxt.Instoffset = 0
aclass(ctxt, a)
return ctxt.Instoffset
}
作者：arnold
项目：g
func preprocess(ctxt *obj.Link, cursym *obj.LSym) {
autosize := int32(0)
ctxt.Cursym = cursym
if cursym.Text == nil || cursym.Text.Link == nil {
return
}
softfloat(ctxt, cursym)
p := cursym.Text
autoffset := int32(p.To.Offset)
if autoffset < 0 {
autoffset = 0
}
cursym.Locals = autoffset
cursym.Args = p.To.Val.(int32)
/*
* find leaf subroutines
* strip NOPs
* expand RET
* expand BECOME pseudo
*/
var q1 *obj.Prog
var q *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 ADIV, ADIVU, AMOD, AMODU:
q = p
if ctxt.Sym_div == nil {
initdiv(ctxt)
}
cursym.Text.Mark &^= LEAF
continue
case obj.ANOP:
q1 = p.Link
q.Link = q1 /* q is non-nop */
if q1 != nil {
q1.Mark |= p.Mark
}
continue
case ABL,
ABX,
obj.ADUFFZERO,
obj.ADUFFCOPY:
cursym.Text.Mark &^= LEAF
fallthrough
case AB,
ABEQ,
ABNE,
ABCS,
ABHS,
ABCC,
ABLO,
ABMI,
ABPL,
ABVS,
ABVC,
ABHI,
ABLS,
ABGE,
ABLT,
ABGT,
ABLE:
q1 = p.Pcond
if q1 != nil {
for q1.As == obj.ANOP {
q1 = q1.Link
p.Pcond = q1
}
}
}
q = p
}
var o int
var p1 *obj.Prog
var p2 *obj.Prog
var q2 *obj.Prog
for p := cursym.Text; p != nil; p = p.Link {
o = int(p.As)
switch o {
case obj.ATEXT:
autosize = int32(p.To.Offset + 4)
if autosize <= 4 {
if cursym.Text.Mark&LEAF != 0 {
p.To.Offset = -4
autosize = 0
//.........这里部分代码省略.........
作者：gmw
项目：g
func preprocess(ctxt *obj.Link, cursym *obj.LSym) {
// TODO(minux): add morestack short-cuts with small fixed frame-size.
ctxt.Cursym = cursym
if cursym.Text == nil || cursym.Text.Link == nil {
return
}
p := cursym.Text
textstksiz := p.To.Offset
if textstksiz == -8 {
// Compatibility hack.
p.From3.Offset |= obj.NOFRAME
textstksiz = 0
}
if textstksiz%8 != 0 {
ctxt.Diag("frame size %d not a multiple of 8", textstksiz)
}
if p.From3.Offset&obj.NOFRAME != 0 {
if textstksiz != 0 {
ctxt.Diag("NOFRAME functions must have a frame size of 0, not %d", textstksiz)
}
}
cursym.Args = p.To.Val.(int32)
cursym.Locals = int32(textstksiz)
/*
* find leaf subroutines
* strip NOPs
* expand RET
* expand BECOME pseudo
*/
if ctxt.Debugvlog != 0 {
fmt.Fprintf(ctxt.Bso, "%5.2f noops\n", obj.Cputime())
}
ctxt.Bso.Flush()
var q *obj.Prog
var q1 *obj.Prog
for p := cursym.Text; p != nil; p = p.Link {
switch p.As {
/* too hard, just leave alone */
case obj.ATEXT:
q = p
p.Mark |= LABEL | LEAF | SYNC
if p.Link != nil {
p.Link.Mark |= LABEL
}
case ANOR:
q = p
if p.To.Type == obj.TYPE_REG {
if p.To.Reg == REGZERO {
p.Mark |= LABEL | SYNC
}
}
case ALWAR,
ASTWCCC,
AECIWX,
AECOWX,
AEIEIO,
AICBI,
AISYNC,
ATLBIE,
ATLBIEL,
ASLBIA,
ASLBIE,
ASLBMFEE,
ASLBMFEV,
ASLBMTE,
ADCBF,
ADCBI,
ADCBST,
ADCBT,
ADCBTST,
ADCBZ,
ASYNC,
ATLBSYNC,
APTESYNC,
ATW,
AWORD,
ARFI,
ARFCI,
ARFID,
AHRFID:
q = p
p.Mark |= LABEL | SYNC
continue
case AMOVW, AMOVWZ, AMOVD:
q = p
if p.From.Reg >= REG_SPECIAL || p.To.Reg >= REG_SPECIAL {
p.Mark |= LABEL | SYNC
}
continue
case AFABS,
//.........这里部分代码省略.........
作者：gmw
项目：g
// 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 [email protected], R12
// ADD $offset, R12
// MOVD R12, CTR
// BL (CTR)
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 = REG_R12
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 = REG_R12
p2 := obj.Appendp(ctxt, p1)
p2.As = AMOVD
p2.From.Type = obj.TYPE_REG
p2.From.Reg = REG_R12
p2.To.Type = obj.TYPE_REG
p2.To.Reg = REG_CTR
p3 := obj.Appendp(ctxt, p2)
p3.As = obj.ACALL
p3.From.Type = obj.TYPE_REG
p3.From.Reg = REG_R12
p3.To.Type = obj.TYPE_REG
p3.To.Reg = REG_CTR
}
// 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 [email protected], Rx
// MOVD $sym+<off>, Rx becomes MOVD [email protected], 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 [email protected], REGTMP; MOVx (REGTMP), Ry
// MOVx Ry, sym becomes MOVD [email protected], REGTMP; MOVx 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
//.........这里部分代码省略.........
作者：gmw
项目：g
func xfol(ctxt *obj.Link, p *obj.Prog, last **obj.Prog) {
var q *obj.Prog
var r *obj.Prog
var a int
var b int
var i int
loop:
if p == nil {
return
}
a = int(p.As)
if a == ABR {
q = p.Pcond
if (p.Mark&NOSCHED != 0) || q != nil && (q.Mark&NOSCHED != 0) {
p.Mark |= FOLL
(*last).Link = p
*last = p
p = p.Link
xfol(ctxt, p, last)
p = q
if p != nil && p.Mark&FOLL == 0 {
goto loop
}
return
}
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.Mark&NOSCHED != 0) {
break
}
b = 0 /* set */
a = int(q.As)
if a == obj.ANOP {
i--
continue
}
if a == ABR || a == obj.ARET || a == ARFI || a == ARFCI || a == ARFID || a == AHRFID {
goto copy
}
if q.Pcond == nil || (q.Pcond.Mark&FOLL != 0) {
continue
}
b = relinv(a)
if b == 0 {
continue
}
copy:
for {
r = ctxt.NewProg()
*r = *p
if r.Mark&FOLL == 0 {
fmt.Printf("cant 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 == ABR || a == obj.ARET || a == ARFI || a == ARFCI || a == ARFID || a == AHRFID {
return
}
r.As = int16(b)
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("cant happen 2\n")
}
return
}
}
a = ABR
q = ctxt.NewProg()
q.As = int16(a)
q.Lineno = p.Lineno
q.To.Type = obj.TYPE_BRANCH
q.To.Offset = p.Pc
//.........这里部分代码省略.........
作者：hurkg
项目：g
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,
//.........这里部分代码省略.........
作者：Harvey-O
项目：g
func opirr(ctxt *obj.Link, a obj.As) uint32 {
switch a {
case AADD:
return SP(1, 0)
case AADDU:
return SP(1, 1)
case ASGT:
return SP(1, 2)
case ASGTU:
return SP(1, 3)
case AAND:
return SP(1, 4)
case AOR:
return SP(1, 5)
case AXOR:
return SP(1, 6)
case ALUI:
return SP(1, 7)
case ASLL:
return OP(0, 0)
case ASRL:
return OP(0, 2)
case ASRA:
return OP(0, 3)
case AADDV:
return SP(3, 0)
case AADDVU:
return SP(3, 1)
case AJMP:
return SP(0, 2)
case AJAL,
obj.ADUFFZERO,
obj.ADUFFCOPY:
return SP(0, 3)
case ABEQ:
return SP(0, 4)
case -ABEQ:
return SP(2, 4) /* likely */
case ABNE:
return SP(0, 5)
case -ABNE:
return SP(2, 5) /* likely */
case ABGEZ:
return SP(0, 1) | BCOND(0, 1)
case -ABGEZ:
return SP(0, 1) | BCOND(0, 3) /* likely */
case ABGEZAL:
return SP(0, 1) | BCOND(2, 1)
case -ABGEZAL:
return SP(0, 1) | BCOND(2, 3) /* likely */
case ABGTZ:
return SP(0, 7)
case -ABGTZ:
return SP(2, 7) /* likely */
case ABLEZ:
return SP(0, 6)
case -ABLEZ:
return SP(2, 6) /* likely */
case ABLTZ:
return SP(0, 1) | BCOND(0, 0)
case -ABLTZ:
return SP(0, 1) | BCOND(0, 2) /* likely */
case ABLTZAL:
return SP(0, 1) | BCOND(2, 0)
case -ABLTZAL:
return SP(0, 1) | BCOND(2, 2) /* likely */
case ABFPT:
return SP(2, 1) | (257 << 16)
case -ABFPT:
return SP(2, 1) | (259 << 16) /* likely */
case ABFPF:
return SP(2, 1) | (256 << 16)
case -ABFPF:
return SP(2, 1) | (258 << 16) /* likely */
case AMOVB,
AMOVBU:
return SP(5, 0)
case AMOVH,
AMOVHU:
return SP(5, 1)
case AMOVW,
AMOVWU:
return SP(5, 3)
case AMOVV:
return SP(7, 7)
case AMOVF:
return SP(7, 1)
case AMOVD:
return SP(7, 5)
case AMOVWL:
return SP(5, 2)
case AMOVWR:
return SP(5, 6)
case AMOVVL:
return SP(5, 4)
case AMOVVR:
return SP(5, 5)
//.........这里部分代码省略.........
作者：Harvey-O
项目：g
func asmout(ctxt *obj.Link, p *obj.Prog, o *Optab, out []uint32) {
o1 := uint32(0)
o2 := uint32(0)
o3 := uint32(0)
o4 := uint32(0)
add := AADDU
if ctxt.Mode&Mips64 != 0 {
add = AADDVU
}
switch o.type_ {
default:
ctxt.Diag("unknown type %d %v", o.type_)
prasm(p)
case 0: /* pseudo ops */
break
case 1: /* mov r1,r2 ==> OR r1,r0,r2 */
a := AOR
if p.As == AMOVW && ctxt.Mode&Mips64 != 0 {
a = AADDU // sign-extended to high 32 bits
}
o1 = OP_RRR(oprrr(ctxt, a), uint32(REGZERO), uint32(p.From.Reg), uint32(p.To.Reg))
case 2: /* add/sub r1,[r2],r3 */
r := int(p.Reg)
if r == 0 {
r = int(p.To.Reg)
}
o1 = OP_RRR(oprrr(ctxt, p.As), uint32(p.From.Reg), uint32(r), uint32(p.To.Reg))
case 3: /* mov $soreg, r ==> or/add $i,o,r */
v := regoff(ctxt, &p.From)
r := int(p.From.Reg)
if r == 0 {
r = int(o.param)
}
a := add
if o.a1 == C_ANDCON {
a = AOR
}
o1 = OP_IRR(opirr(ctxt, a), uint32(v), uint32(r), uint32(p.To.Reg))
case 4: /* add $scon,[r1],r2 */
v := regoff(ctxt, &p.From)
r := int(p.Reg)
if r == 0 {
r = int(p.To.Reg)
}
o1 = OP_IRR(opirr(ctxt, p.As), uint32(v), uint32(r), uint32(p.To.Reg))
case 5: /* syscall */
o1 = oprrr(ctxt, p.As)
case 6: /* beq r1,[r2],sbra */
v := int32(0)
if p.Pcond == nil {
v = int32(-4) >> 2
} else {
v = int32(p.Pcond.Pc-p.Pc-4) >> 2
}
if (v<<16)>>16 != v {
ctxt.Diag("short branch too far\n%v", p)
}
o1 = OP_IRR(opirr(ctxt, p.As), uint32(v), uint32(p.From.Reg), uint32(p.Reg))
// for ABFPT and ABFPF only: always fill delay slot with 0
// see comments in func preprocess for details.
o2 = 0
case 7: /* mov r, soreg ==> sw o(r) */
r := int(p.To.Reg)
if r == 0 {
r = int(o.param)
}
v := regoff(ctxt, &p.To)
o1 = OP_IRR(opirr(ctxt, p.As), uint32(v), uint32(r), uint32(p.From.Reg))
case 8: /* mov soreg, r ==> lw o(r) */
r := int(p.From.Reg)
if r == 0 {
r = int(o.param)
}
v := regoff(ctxt, &p.From)
o1 = OP_IRR(opirr(ctxt, -p.As), uint32(v), uint32(r), uint32(p.To.Reg))
case 9: /* sll r1,[r2],r3 */
r := int(p.Reg)
if r == 0 {
r = int(p.To.Reg)
}
o1 = OP_RRR(oprrr(ctxt, p.As), uint32(r), uint32(p.From.Reg), uint32(p.To.Reg))
//.........这里部分代码省略.........
作者：duhaibo040
项目：go-
func progedit(ctxt *obj.Link, p *obj.Prog) {
// Maintain information about code generation mode.
if ctxt.Mode == 0 {
ctxt.Mode = ctxt.Arch.Regsize * 8
}
p.Mode = int8(ctxt.Mode)
switch p.As {
case AMODE:
if p.From.Type == obj.TYPE_CONST || (p.From.Type == obj.TYPE_MEM && p.From.Reg == REG_NONE) {
switch int(p.From.Offset) {
case 16, 32, 64:
ctxt.Mode = int(p.From.Offset)
}
}
obj.Nopout(p)
}
// Thread-local storage references use the TLS pseudo-register.
// As a register, TLS refers to the thread-local storage base, and it
// can only be loaded into another register:
//
// MOVQ TLS, AX
//
// An offset from the thread-local storage base is written off(reg)(TLS*1).
// Semantically it is off(reg), but the (TLS*1) annotation marks this as
// indexing from the loaded TLS base. This emits a relocation so that
// if the linker needs to adjust the offset, it can. For example:
//
// MOVQ TLS, AX
// MOVQ 0(AX)(TLS*1), CX // load g into CX
//
// On systems that support direct access to the TLS memory, this
// pair of instructions can be reduced to a direct TLS memory reference:
//
// MOVQ 0(TLS), CX // load g into CX
//
// The 2-instruction and 1-instruction forms correspond to the two code
// sequences for loading a TLS variable in the local exec model given in "ELF
// Handling For Thread-Local Storage".
//
// We apply this rewrite on systems that support the 1-instruction form.
// The decision is made using only the operating system and the -shared flag,
// not the link mode. If some link modes on a particular operating system
// require the 2-instruction form, then all builds for that operating system
// will use the 2-instruction form, so that the link mode decision can be
// delayed to link time.
//
// In this way, all supported systems use identical instructions to
// access TLS, and they are rewritten appropriately first here in
// liblink and then finally using relocations in the linker.
//
// When -shared is passed, we leave the code in the 2-instruction form but
// assemble (and relocate) them in different ways to generate the initial
// exec code sequence. It's a bit of a fluke that this is possible without
// rewriting the instructions more comprehensively, and it only does because
// we only support a single TLS variable (g).
if CanUse1InsnTLS(ctxt) {
// Reduce 2-instruction sequence to 1-instruction sequence.
// Sequences like
// MOVQ TLS, BX
// ... off(BX)(TLS*1) ...
// become
// NOP
// ... off(TLS) ...
//
// TODO(rsc): Remove the Hsolaris special case. It exists only to
// guarantee we are producing byte-identical binaries as before this code.
// But it should be unnecessary.
if (p.As == AMOVQ || p.As == AMOVL) && p.From.Type == obj.TYPE_REG && p.From.Reg == REG_TLS && p.To.Type == obj.TYPE_REG && REG_AX <= p.To.Reg && p.To.Reg <= REG_R15 && ctxt.Headtype != obj.Hsolaris {
obj.Nopout(p)
}
if p.From.Type == obj.TYPE_MEM && p.From.Index == REG_TLS && REG_AX <= p.From.Reg && p.From.Reg <= REG_R15 {
p.From.Reg = REG_TLS
p.From.Scale = 0
p.From.Index = REG_NONE
}
if p.To.Type == obj.TYPE_MEM && p.To.Index == REG_TLS && REG_AX <= p.To.Reg && p.To.Reg <= REG_R15 {
p.To.Reg = REG_TLS
p.To.Scale = 0
p.To.Index = REG_NONE
}
} else {
// load_g_cx, below, always inserts the 1-instruction sequence. Rewrite it
// as the 2-instruction sequence if necessary.
// MOVQ 0(TLS), BX
// becomes
// MOVQ TLS, BX
// MOVQ 0(BX)(TLS*1), BX
if (p.As == AMOVQ || p.As == AMOVL) && p.From.Type == obj.TYPE_MEM && p.From.Reg == REG_TLS && p.To.Type == obj.TYPE_REG && REG_AX <= p.To.Reg && p.To.Reg <= REG_R15 {
q := obj.Appendp(ctxt, p)
q.As = p.As
q.From = p.From
q.From.Type = obj.TYPE_MEM
q.From.Reg = p.To.Reg
q.From.Index = REG_TLS
q.From.Scale = 2 // TODO: use 1
q.To = p.To
//.........这里部分代码省略.........
