作者：glycerin
项目：zygomy
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：glycerin
项目：zygomy
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：glycerin
项目：zygomy
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：glycerin
项目：zygomy
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：glycerin
项目：zygomy
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：glycerin
项目：zygomy
// 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
// MOVW [email protected], R9
// ADD $offset, R9
// CALL (R9)
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 = AMOVW
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_R9
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_R9
p2 := obj.Appendp(ctxt, p1)
p2.As = obj.ACALL
p2.To.Type = obj.TYPE_MEM
p2.To.Reg = REG_R9
return
}
// 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 {
// MOVW $sym, Rx becomes MOVW [email protected], Rx
// MOVW $sym+<off>, Rx becomes MOVW [email protected], Rx; ADD <off>, Rx
if p.As != AMOVW {
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 MOVW [email protected], R9; MOVx (R9), Ry
// MOVx Ry, sym becomes MOVW [email protected], R9; MOVx Ry, (R9)
// 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 = AMOVW
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 = REG_R9
p2.As = p.As
p2.From = p.From
p2.To = p.To
if p.From.Name == obj.NAME_EXTERN {
//.........这里部分代码省略.........
作者：glycerin
项目：zygomy
func xfol(ctxt *obj.Link, p *obj.Prog, last **obj.Prog) {
var q *obj.Prog
var r *obj.Prog
var b obj.As
for p != nil {
a := 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
(*last).Pc = pc_cnt
pc_cnt += 1
p = p.Link
xfol(ctxt, p, last)
p = q
if p != nil && p.Mark&FOLL == 0 {
continue
}
return
}
if q != nil {
p.Mark |= FOLL
p = q
if p.Mark&FOLL == 0 {
continue
}
}
}
if p.Mark&FOLL != 0 {
q = p
for i := 0; i < 4; i, q = i+1, q.Link {
if q == *last || (q.Mark&NOSCHED != 0) {
break
}
b = 0 /* set */
a = q.As
if a == obj.ANOP {
i--
continue
}
if a != ABR && a != obj.ARET {
if q.Pcond == nil || (q.Pcond.Mark&FOLL != 0) {
continue
}
b = relinv(a)
if b == 0 {
continue
}
}
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
(*last).Pc = pc_cnt
pc_cnt += 1
continue
}
(*last).Link = r
*last = r
(*last).Pc = pc_cnt
pc_cnt += 1
if a == ABR || a == obj.ARET {
return
}
r.As = 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("can't happen 2\n")
}
return
}
}
a = ABR
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
}
//.........这里部分代码省略.........
作者：glycerin
项目：zygomy
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 ASYNC,
AWORD:
q = p
p.Mark |= LABEL | SYNC
continue
case AMOVW, AMOVWZ, AMOVD:
q = p
if p.From.Reg >= REG_RESERVED || p.To.Reg >= REG_RESERVED {
p.Mark |= LABEL | SYNC
}
continue
case AFABS,
AFADD,
AFDIV,
AFMADD,
AFMOVD,
AFMOVS,
AFMSUB,
AFMUL,
AFNABS,
AFNEG,
AFNMADD,
AFNMSUB,
ALEDBR,
ALDEBR,
AFSUB:
q = p
p.Mark |= FLOAT
continue
case ABL,
ABCL,
obj.ADUFFZERO,
obj.ADUFFCOPY:
cursym.Text.Mark &^= LEAF
fallthrough
case ABC,
//.........这里部分代码省略.........
作者：glycerin
项目：zygomy
// Rewrite p, if necessary, to access global data via the global offset table.
func rewriteToUseGot(ctxt *obj.Link, p *obj.Prog) {
// At the moment EXRL instructions are not emitted by the compiler and only reference local symbols in
// assembly code.
if p.As == AEXRL {
return
}
// 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.To.Type != obj.TYPE_REG || p.As != AMOVD {
ctxt.Diag("do not know how to handle LEA-type insn to non-register in %v with -dynlink", p)
}
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 = 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
// MOVD sym, Ry becomes MOVD [email protected], REGTMP; MOVD (REGTMP), Ry
// MOVD Ry, sym becomes MOVD [email protected], 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)
}
作者：glycerin
项目：zygomy
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
*/
ctxt.Bso.Flush()
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
//.........这里部分代码省略.........
作者：glycerin
项目：zygomy
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.........
作者：glycerin
项目：zygomy
func span0(ctxt *obj.Link, cursym *obj.LSym) {
p := cursym.Text
if p == nil || p.Link == nil { // handle external functions and ELF section symbols
return
}
ctxt.Cursym = cursym
ctxt.Autosize = int32(p.To.Offset + 8)
if oprange[AOR&obj.AMask] == nil {
buildop(ctxt)
}
c := int64(0)
p.Pc = c
var m int
var o *Optab
for p = p.Link; p != nil; p = p.Link {
ctxt.Curp = p
p.Pc = c
o = oplook(ctxt, p)
m = int(o.size)
if m == 0 {
if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != obj.AUSEFIELD {
ctxt.Diag("zero-width instruction\n%v", p)
}
continue
}
c += int64(m)
}
cursym.Size = c
/*
* if any procedure is large enough to
* generate a large SBRA branch, then
* generate extra passes putting branches
* around jmps to fix. this is rare.
*/
bflag := 1
var otxt int64
var q *obj.Prog
for bflag != 0 {
if ctxt.Debugvlog != 0 {
fmt.Fprintf(ctxt.Bso, "%5.2f span1\n", obj.Cputime())
}
bflag = 0
c = 0
for p = cursym.Text.Link; p != nil; p = p.Link {
p.Pc = c
o = oplook(ctxt, p)
// very large conditional branches
if o.type_ == 6 && p.Pcond != nil {
otxt = p.Pcond.Pc - c
if otxt < -(1<<17)+10 || otxt >= (1<<17)-10 {
q = ctxt.NewProg()
q.Link = p.Link
p.Link = q
q.As = AJMP
q.Lineno = p.Lineno
q.To.Type = obj.TYPE_BRANCH
q.Pcond = p.Pcond
p.Pcond = q
q = ctxt.NewProg()
q.Link = p.Link
p.Link = q
q.As = AJMP
q.Lineno = p.Lineno
q.To.Type = obj.TYPE_BRANCH
q.Pcond = q.Link.Link
addnop(ctxt, p.Link)
addnop(ctxt, p)
bflag = 1
}
}
m = int(o.size)
if m == 0 {
if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != obj.AUSEFIELD {
ctxt.Diag("zero-width instruction\n%v", p)
}
continue
}
c += int64(m)
}
cursym.Size = c
}
c += -c & (FuncAlign - 1)
cursym.Size = c
/*
* lay out the code, emitting code and data relocations.
*/
//.........这里部分代码省略.........
作者：glycerin
项目：zygomy
func softfloat(ctxt *obj.Link, cursym *obj.LSym) {
if ctxt.Goarm > 5 {
return
}
symsfloat := obj.Linklookup(ctxt, "_sfloat", 0)
wasfloat := 0
for p := cursym.Text; p != nil; p = p.Link {
if p.Pcond != nil {
p.Pcond.Mark |= LABEL
}
}
var next *obj.Prog
for p := cursym.Text; p != nil; p = p.Link {
switch p.As {
case AMOVW:
if isfloatreg(&p.To) || isfloatreg(&p.From) {
goto soft
}
goto notsoft
case AMOVWD,
AMOVWF,
AMOVDW,
AMOVFW,
AMOVFD,
AMOVDF,
AMOVF,
AMOVD,
ACMPF,
ACMPD,
AADDF,
AADDD,
ASUBF,
ASUBD,
AMULF,
AMULD,
ADIVF,
ADIVD,
ASQRTF,
ASQRTD,
AABSF,
AABSD:
goto soft
default:
goto notsoft
}
soft:
if wasfloat == 0 || (p.Mark&LABEL != 0) {
next = ctxt.NewProg()
*next = *p
// BL _sfloat(SB)
*p = obj.Prog{}
p.Ctxt = ctxt
p.Link = next
p.As = ABL
p.To.Type = obj.TYPE_BRANCH
p.To.Sym = symsfloat
p.Lineno = next.Lineno
p = next
wasfloat = 1
}
continue
notsoft:
wasfloat = 0
}
}
作者：glycerin
项目：zygomy
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,
ALBAR,
ASTBCCC,
ASTWCCC,
AECIWX,
AECOWX,
AEIEIO,
AICBI,
AISYNC,
ATLBIE,
ATLBIEL,
ASLBIA,
ASLBIE,
ASLBMFEE,
ASLBMFEV,
ASLBMTE,
ADCBF,
ADCBI,
ADCBST,
ADCBT,
ADCBTST,
ADCBZ,
ASYNC,
ATLBSYNC,
APTESYNC,
ALWSYNC,
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
}
//.........这里部分代码省略.........
作者：glycerin
项目：zygomy
func xfol(ctxt *obj.Link, p *obj.Prog, last **obj.Prog) {
var q *obj.Prog
var r *obj.Prog
var b obj.As
var i int
loop:
if p == nil {
return
}
a := 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 = 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("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 == ABR || a == obj.ARET || a == ARFI || a == ARFCI || a == ARFID || a == AHRFID {
return
}
r.As = 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("can't happen 2\n")
}
return
}
}
a = ABR
q = ctxt.NewProg()
q.As = a
q.Lineno = p.Lineno
q.To.Type = obj.TYPE_BRANCH
q.To.Offset = p.Pc
q.Pcond = p
//.........这里部分代码省略.........
作者：glycerin
项目：zygomy
func asmout(ctxt *obj.Link, p *obj.Prog, o *Optab, out []uint32) {
o1 := uint32(0)
o2 := uint32(0)
o3 := uint32(0)
o4 := uint32(0)
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 {
a = AADDU // sign-extended to high 32 bits
}
o1 = OP_RRR(oprrr(ctxt, a), uint32(p.From.Reg), uint32(REGZERO), 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 := AADDVU
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))
case 10: /* add $con,[r1],r2 ==> mov $con, t; add t,[r1],r2 */
v := regoff(ctxt, &p.From)
a := AOR
if v < 0 {
a = AADDU
//.........这里部分代码省略.........
作者：glycerin
项目：zygomy
func buildop(ctxt *obj.Link) {
var n int
for i := 0; i < C_NCLASS; i++ {
for n = 0; n < C_NCLASS; n++ {
if cmp(n, i) {
xcmp[i][n] = true
}
}
}
for n = 0; optab[n].as != obj.AXXX; n++ {
}
sort.Sort(ocmp(optab[:n]))
for i := 0; i < n; i++ {
r := optab[i].as
r0 := r & obj.AMask
start := i
for optab[i].as == r {
i++
}
oprange[r0] = optab[start:i]
i--
switch r {
default:
ctxt.Diag("unknown op in build: %v", obj.Aconv(r))
log.Fatalf("bad code")
case AABSF:
opset(AMOVFD, r0)
opset(AMOVDF, r0)
opset(AMOVWF, r0)
opset(AMOVFW, r0)
opset(AMOVWD, r0)
opset(AMOVDW, r0)
opset(ANEGF, r0)
opset(ANEGD, r0)
opset(AABSD, r0)
opset(ATRUNCDW, r0)
opset(ATRUNCFW, r0)
opset(ATRUNCDV, r0)
opset(ATRUNCFV, r0)
opset(AMOVVF, r0)
opset(AMOVFV, r0)
opset(AMOVVD, r0)
opset(AMOVDV, r0)
case AADD:
opset(ASGT, r0)
opset(ASGTU, r0)
opset(AADDU, r0)
opset(AADDV, r0)
opset(AADDVU, r0)
case AADDF:
opset(ADIVF, r0)
opset(ADIVD, r0)
opset(AMULF, r0)
opset(AMULD, r0)
opset(ASUBF, r0)
opset(ASUBD, r0)
opset(AADDD, r0)
case AAND:
opset(AOR, r0)
opset(AXOR, r0)
case ABEQ:
opset(ABNE, r0)
case ABLEZ:
opset(ABGEZ, r0)
opset(ABGEZAL, r0)
opset(ABLTZ, r0)
opset(ABLTZAL, r0)
opset(ABGTZ, r0)
case AMOVB:
opset(AMOVH, r0)
case AMOVBU:
opset(AMOVHU, r0)
case AMUL:
opset(AREM, r0)
opset(AREMU, r0)
opset(ADIVU, r0)
opset(AMULU, r0)
opset(ADIV, r0)
opset(ADIVV, r0)
opset(ADIVVU, r0)
opset(AMULV, r0)
opset(AMULVU, r0)
opset(AREMV, r0)
opset(AREMVU, r0)
case ASLL:
opset(ASRL, r0)
opset(ASRA, r0)
opset(ASLLV, r0)
//.........这里部分代码省略.........
作者：glycerin
项目：zygomy
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
if a.Sym.Type == obj.STLSBSS {
return C_TLS
}
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 = a.Offset
goto consize
}
//.........这里部分代码省略.........
作者：glycerin
项目：zygomy
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 p1 *obj.Prog
var p2 *obj.Prog
var q2 *obj.Prog
for p := cursym.Text; p != nil; p = p.Link {
o := 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：glycerin
项目：zygomy
func oprrr(ctxt *obj.Link, a obj.As) uint32 {
switch a {
case AADD:
return OP(4, 0)
case AADDU:
return OP(4, 1)
case ASGT:
return OP(5, 2)
case ASGTU:
return OP(5, 3)
case AAND:
return OP(4, 4)
case AOR:
return OP(4, 5)
case AXOR:
return OP(4, 6)
case ASUB:
return OP(4, 2)
case ASUBU:
return OP(4, 3)
case ANOR:
return OP(4, 7)
case ASLL:
return OP(0, 4)
case ASRL:
return OP(0, 6)
case ASRA:
return OP(0, 7)
case ASLLV:
return OP(2, 4)
case ASRLV:
return OP(2, 6)
case ASRAV:
return OP(2, 7)
case AADDV:
return OP(5, 4)
case AADDVU:
return OP(5, 5)
case ASUBV:
return OP(5, 6)
case ASUBVU:
return OP(5, 7)
case AREM,
ADIV:
return OP(3, 2)
case AREMU,
ADIVU:
return OP(3, 3)
case AMUL:
return OP(3, 0)
case AMULU:
return OP(3, 1)
case AREMV,
ADIVV:
return OP(3, 6)
case AREMVU,
ADIVVU:
return OP(3, 7)
case AMULV:
return OP(3, 4)
case AMULVU:
return OP(3, 5)
case AJMP:
return OP(1, 0)
case AJAL:
return OP(1, 1)
case ABREAK:
return OP(1, 5)
case ASYSCALL:
return OP(1, 4)
case ATLBP:
return MMU(1, 0)
case ATLBR:
return MMU(0, 1)
case ATLBWI:
return MMU(0, 2)
case ATLBWR:
return MMU(0, 6)
case ARFE:
return MMU(2, 0)
case ADIVF:
return FPF(0, 3)
case ADIVD:
return FPD(0, 3)
case AMULF:
return FPF(0, 2)
case AMULD:
return FPD(0, 2)
case ASUBF:
return FPF(0, 1)
case ASUBD:
return FPD(0, 1)
case AADDF:
return FPF(0, 0)
case AADDD:
return FPD(0, 0)
case ATRUNCFV:
//.........这里部分代码省略.........
