1 // Derived from Inferno utils/6c/txt.c
2 // http://code.google.com/p/inferno-os/source/browse/utils/6c/txt.c
4 // Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved.
5 // Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
6 // Portions Copyright © 1997-1999 Vita Nuova Limited
7 // Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
8 // Portions Copyright © 2004,2006 Bruce Ellis
9 // Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
10 // Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
11 // Portions Copyright © 2009 The Go Authors. All rights reserved.
13 // Permission is hereby granted, free of charge, to any person obtaining a copy
14 // of this software and associated documentation files (the "Software"), to deal
15 // in the Software without restriction, including without limitation the rights
16 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
17 // copies of the Software, and to permit persons to whom the Software is
18 // furnished to do so, subject to the following conditions:
20 // The above copyright notice and this permission notice shall be included in
21 // all copies or substantial portions of the Software.
23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
24 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
25 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
26 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
27 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
28 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
46 // Is this node a memory operand?
47 func Ismem(n *Node) bool {
60 return Thearch.Thechar == '6' || Thearch.Thechar == '9' // because 6g uses PC-relative addressing; TODO(rsc): not sure why 9g too
66 func Samereg(a *Node, b *Node) bool {
67 if a == nil || b == nil {
70 if a.Op != OREGISTER {
73 if b.Op != OREGISTER {
82 func Gbranch(as int, t *Type, likely int) *obj.Prog {
84 p.To.Type = obj.TYPE_BRANCH
86 if as != obj.AJMP && likely != 0 && Thearch.Thechar != '9' && Thearch.Thechar != '7' && Thearch.Thechar != '0' {
87 p.From.Type = obj.TYPE_CONST
100 func Prog(as int) *obj.Prog {
103 if as == obj.ADATA || as == obj.AGLOBL {
105 Fatalf("already dumped data")
133 func Nodreg(n *Node, t *Type, r int) {
135 Fatalf("nodreg: t nil")
146 func Nodindreg(n *Node, t *Type, r int) {
151 func Afunclit(a *obj.Addr, n *Node) {
152 if a.Type == obj.TYPE_ADDR && a.Name == obj.NAME_EXTERN {
153 a.Type = obj.TYPE_MEM
154 a.Sym = Linksym(n.Sym)
158 func Clearp(p *obj.Prog) {
176 // Fixup instructions after allocauto (formerly compactframe) has moved all autos around.
177 func fixautoused(p *obj.Prog) {
183 if p.As == obj.ATYPE && p.From.Node != nil && p.From.Name == obj.NAME_AUTO && !((p.From.Node).(*Node)).Used {
188 if (p.As == obj.AVARDEF || p.As == obj.AVARKILL || p.As == obj.AVARLIVE) && p.To.Node != nil && !((p.To.Node).(*Node)).Used {
189 // Cannot remove VARDEF instruction, because - unlike TYPE handled above -
190 // VARDEFs are interspersed with other code, and a jump might be using the
191 // VARDEF as a target. Replace with a no-op instead. A later pass will remove
198 if p.From.Name == obj.NAME_AUTO && p.From.Node != nil {
199 p.From.Offset += stkdelta[p.From.Node.(*Node)]
202 if p.To.Name == obj.NAME_AUTO && p.To.Node != nil {
203 p.To.Offset += stkdelta[p.To.Node.(*Node)]
210 func ggloblnod(nam *Node) {
211 p := Thearch.Gins(obj.AGLOBL, nam, nil)
212 p.Lineno = nam.Lineno
213 p.From.Sym.Gotype = Linksym(ngotype(nam))
215 p.To.Type = obj.TYPE_CONST
216 p.To.Offset = nam.Type.Width
217 p.From3 = new(obj.Addr)
218 if nam.Name.Readonly {
219 p.From3.Offset = obj.RODATA
221 if nam.Type != nil && !haspointers(nam.Type) {
222 p.From3.Offset |= obj.NOPTR
226 func ggloblsym(s *Sym, width int32, flags int16) {
227 p := Thearch.Gins(obj.AGLOBL, nil, nil)
228 p.From.Type = obj.TYPE_MEM
229 p.From.Name = obj.NAME_EXTERN
230 p.From.Sym = Linksym(s)
231 if flags&obj.LOCAL != 0 {
232 p.From.Sym.Local = true
235 p.To.Type = obj.TYPE_CONST
236 p.To.Offset = int64(width)
237 p.From3 = new(obj.Addr)
238 p.From3.Offset = int64(flags)
241 func gjmp(to *obj.Prog) *obj.Prog {
242 p := Gbranch(obj.AJMP, nil, 0)
249 func gtrack(s *Sym) {
250 p := Thearch.Gins(obj.AUSEFIELD, nil, nil)
251 p.From.Type = obj.TYPE_MEM
252 p.From.Name = obj.NAME_EXTERN
253 p.From.Sym = Linksym(s)
256 func gused(n *Node) {
257 Thearch.Gins(obj.ANOP, n, nil) // used
260 func Isfat(t *Type) bool {
263 case TSTRUCT, TARRAY, TSTRING,
264 TINTER: // maybe remove later
272 // Sweep the prog list to mark any used nodes.
273 func markautoused(p *obj.Prog) {
274 for ; p != nil; p = p.Link {
275 if p.As == obj.ATYPE || p.As == obj.AVARDEF || p.As == obj.AVARKILL {
279 if p.From.Node != nil {
280 ((p.From.Node).(*Node)).Used = true
283 if p.To.Node != nil {
284 ((p.To.Node).(*Node)).Used = true
289 // Naddr rewrites a to refer to n.
290 // It assumes that a is zeroed on entry.
291 func Naddr(a *obj.Addr, n *Node) {
296 if n.Type != nil && n.Type.Etype != TIDEAL {
297 // TODO(rsc): This is undone by the selective clearing of width below,
298 // to match architectures that were not as aggressive in setting width
299 // during naddr. Those widths must be cleared to avoid triggering
300 // failures in gins when it detects real but heretofore latent (and one
301 // hopes innocuous) type mismatches.
302 // The type mismatches should be fixed and the clearing below removed.
305 a.Width = n.Type.Width
310 a := a // copy to let escape into Ctxt.Dconv
313 Fatalf("naddr: bad %v %v", Oconv(int(n.Op), 0), Ctxt.Dconv(a))
316 a.Type = obj.TYPE_REG
319 if Thearch.Thechar == '8' { // TODO(rsc): Never clear a->width.
324 a.Type = obj.TYPE_MEM
326 a.Sym = Linksym(n.Sym)
328 if a.Offset != int64(int32(a.Offset)) {
329 Yyerror("offset %d too large for OINDREG", a.Offset)
331 if Thearch.Thechar == '8' { // TODO(rsc): Never clear a->width.
335 // n->left is PHEAP ONAME for stack parameter.
336 // compute address of actual parameter on stack.
338 a.Etype = uint8(Simtype[n.Left.Type.Etype])
340 a.Width = n.Left.Type.Width
342 a.Sym = Linksym(n.Left.Sym)
343 a.Type = obj.TYPE_MEM
344 a.Name = obj.NAME_PARAM
348 if !Curfn.Func.Needctxt {
349 Fatalf("closurevar without needctxt")
351 a.Type = obj.TYPE_MEM
352 a.Reg = int16(Thearch.REGCTXT)
358 a.Sym = Linksym(n.Left.Sym)
363 a.Etype = uint8(Simtype[n.Type.Etype])
369 //if(a->node >= (Node*)&n)
370 // fatal("stack node");
372 s = Lookup(".noname")
376 if n.Type.Sym != nil {
377 if n.Type.Sym.Pkg != nil {
378 s = Pkglookup(s.Name, n.Type.Sym.Pkg)
384 a.Type = obj.TYPE_MEM
387 Fatalf("naddr: ONAME class %v %d\n", n.Sym, n.Class)
390 a.Name = obj.NAME_EXTERN
393 a.Name = obj.NAME_AUTO
395 case PPARAM, PPARAMOUT:
396 a.Name = obj.NAME_PARAM
399 a.Name = obj.NAME_EXTERN
400 a.Type = obj.TYPE_ADDR
401 a.Width = int64(Widthptr)
408 // A special case to make write barriers more efficient.
409 // Taking the address of the first field of a named struct
410 // is the same as taking the address of the struct.
411 if n.Left.Type.Etype != TSTRUCT || n.Left.Type.Type.Sym != n.Right.Sym {
414 Fatalf("naddr: bad %v %v", Oconv(int(n.Op), 0), Ctxt.Dconv(a))
419 if Thearch.Thechar == '8' {
422 switch n.Val().Ctype() {
424 Fatalf("naddr: const %v", Tconv(n.Type, obj.FmtLong))
427 a.Type = obj.TYPE_FCONST
428 a.Val = mpgetflt(n.Val().U.(*Mpflt))
432 a.Type = obj.TYPE_CONST
433 a.Offset = Mpgetfix(n.Val().U.(*Mpint))
436 datagostring(n.Val().U.(string), a)
440 a.Type = obj.TYPE_CONST
441 a.Offset = int64(obj.Bool2int(n.Val().U.(bool)))
445 a.Type = obj.TYPE_CONST
451 a.Etype = uint8(Tptr)
452 if Thearch.Thechar != '0' && Thearch.Thechar != '5' && Thearch.Thechar != '7' && Thearch.Thechar != '9' { // TODO(rsc): Do this even for arm, ppc64.
453 a.Width = int64(Widthptr)
455 if a.Type != obj.TYPE_MEM {
456 a := a // copy to let escape into Ctxt.Dconv
457 Fatalf("naddr: OADDR %v (from %v)", Ctxt.Dconv(a), Oconv(int(n.Left.Op), 0))
459 a.Type = obj.TYPE_ADDR
461 // itable of interface value
465 if a.Type == obj.TYPE_CONST && a.Offset == 0 {
468 a.Etype = uint8(Tptr)
469 a.Width = int64(Widthptr)
471 // pointer in a string or slice
475 if a.Type == obj.TYPE_CONST && a.Offset == 0 {
478 a.Etype = uint8(Simtype[Tptr])
479 a.Offset += int64(Array_array)
480 a.Width = int64(Widthptr)
482 // len of string or slice
486 if a.Type == obj.TYPE_CONST && a.Offset == 0 {
489 a.Etype = uint8(Simtype[TUINT])
490 a.Offset += int64(Array_nel)
491 if Thearch.Thechar != '5' { // TODO(rsc): Do this even on arm.
492 a.Width = int64(Widthint)
495 // cap of string or slice
499 if a.Type == obj.TYPE_CONST && a.Offset == 0 {
502 a.Etype = uint8(Simtype[TUINT])
503 a.Offset += int64(Array_cap)
504 if Thearch.Thechar != '5' { // TODO(rsc): Do this even on arm.
505 a.Width = int64(Widthint)
511 func newplist() *obj.Plist {
512 pl := obj.Linknewplist(Ctxt)
521 // nodarg does something that depends on the value of
522 // fp (this was previously completely undocumented).
524 // fp=1 corresponds to input args
525 // fp=0 corresponds to output args
526 // fp=-1 is a special case of output args for a
527 // specific call from walk that previously (and
528 // incorrectly) passed a 1; the behavior is exactly
529 // the same as it is for 1, except that PARAMOUT is
530 // generated instead of PARAM.
531 func nodarg(t *Type, fp int) *Node {
534 // entire argument struct, not just one arg
535 if t.Etype == TSTRUCT && t.Funarg {
536 n = Nod(ONAME, nil, nil)
537 n.Sym = Lookup(".args")
540 first := Structfirst(&savet, &t)
542 Fatalf("nodarg: bad struct")
544 if first.Width == BADWIDTH {
545 Fatalf("nodarg: offset not computed for %v", t)
547 n.Xoffset = first.Width
552 if t.Etype != TFIELD {
553 Fatalf("nodarg: not field %v", t)
556 if fp == 1 || fp == -1 {
558 for l := Curfn.Func.Dcl; l != nil; l = l.Next {
560 if (n.Class == PPARAM || n.Class == PPARAMOUT) && !isblanksym(t.Sym) && n.Sym == t.Sym {
566 n = Nod(ONAME, nil, nil)
570 if t.Width == BADWIDTH {
571 Fatalf("nodarg: offset not computed for %v", t)
577 // Rewrite argument named _ to __,
578 // or else the assignment to _ will be
579 // discarded during code generation.
586 case 0: // output arg
589 n.Reg = int16(Thearch.REGSP)
590 n.Xoffset += Ctxt.FixedFrameSize()
595 case -1: // output arg from paramstoheap
598 case 2: // offset output arg
599 Fatalf("shouldn't be used")
606 func Patch(p *obj.Prog, to *obj.Prog) {
607 if p.To.Type != obj.TYPE_BRANCH {
608 Fatalf("patch: not a branch")
614 func unpatch(p *obj.Prog) *obj.Prog {
615 if p.To.Type != obj.TYPE_BRANCH {
616 Fatalf("unpatch: not a branch")
618 q, _ := p.To.Val.(*obj.Prog)
624 var reg [100]int // count of references to reg
625 var regstk [100][]byte // allocation sites, when -v is given
627 func GetReg(r int) int {
628 return reg[r-Thearch.REGMIN]
630 func SetReg(r, v int) {
631 reg[r-Thearch.REGMIN] = v
639 for r := Thearch.REGMIN; r <= Thearch.REGMAX; r++ {
640 reg[r-Thearch.REGMIN] = 0
642 for r := Thearch.FREGMIN; r <= Thearch.FREGMAX; r++ {
643 reg[r-Thearch.REGMIN] = 0
646 for _, r := range Thearch.ReservedRegs {
647 reg[r-Thearch.REGMIN] = 1
652 for _, r := range Thearch.ReservedRegs {
653 reg[r-Thearch.REGMIN]--
656 for r := Thearch.REGMIN; r <= Thearch.REGMAX; r++ {
657 n := reg[r-Thearch.REGMIN]
662 Yyerror("reg %v left allocated", obj.Rconv(r))
666 for r := Thearch.FREGMIN; r <= Thearch.FREGMAX; r++ {
667 n := reg[r-Thearch.REGMIN]
672 Yyerror("reg %v left allocated", obj.Rconv(r))
677 func Anyregalloc() bool {
679 for r := Thearch.REGMIN; r <= Thearch.REGMAX; r++ {
680 if reg[r-Thearch.REGMIN] == 0 {
684 return n > len(Thearch.ReservedRegs)
687 // allocate register of type t, leave in n.
688 // if o != N, o may be reusable register.
689 // caller must Regfree(n).
690 func Regalloc(n *Node, t *Type, o *Node) {
692 Fatalf("regalloc: t nil")
694 et := Simtype[t.Etype]
695 if Ctxt.Arch.Regsize == 4 && (et == TINT64 || et == TUINT64) {
696 Fatalf("regalloc 64bit")
703 Fatalf("regalloc: unknown type %v", t)
705 case TINT8, TUINT8, TINT16, TUINT16, TINT32, TUINT32, TINT64, TUINT64, TPTR32, TPTR64, TBOOL:
706 if o != nil && o.Op == OREGISTER {
708 if Thearch.REGMIN <= i && i <= Thearch.REGMAX {
712 for i = Thearch.REGMIN; i <= Thearch.REGMAX; i++ {
713 if reg[i-Thearch.REGMIN] == 0 {
719 Fatalf("out of fixed registers")
721 case TFLOAT32, TFLOAT64:
723 i = Thearch.FREGMIN // x86.REG_F0
726 if o != nil && o.Op == OREGISTER {
728 if Thearch.FREGMIN <= i && i <= Thearch.FREGMAX {
732 for i = Thearch.FREGMIN; i <= Thearch.FREGMAX; i++ {
733 if reg[i-Thearch.REGMIN] == 0 { // note: REGMIN, not FREGMIN
739 Fatalf("out of floating registers")
741 case TCOMPLEX64, TCOMPLEX128:
746 ix := i - Thearch.REGMIN
747 if reg[ix] == 0 && Debug['v'] > 0 {
748 if regstk[ix] == nil {
749 regstk[ix] = make([]byte, 4096)
752 n := runtime.Stack(stk[:cap(stk)], false)
759 func Regfree(n *Node) {
763 if n.Op != OREGISTER && n.Op != OINDREG {
764 Fatalf("regfree: not a register")
767 if i == Thearch.REGSP {
771 case Thearch.REGMIN <= i && i <= Thearch.REGMAX,
772 Thearch.FREGMIN <= i && i <= Thearch.FREGMAX:
775 Fatalf("regfree: reg out of range")
780 Fatalf("regfree: reg not allocated")
784 regstk[i] = regstk[i][:0]
788 // Reginuse reports whether r is in use.
789 func Reginuse(r int) bool {
791 case Thearch.REGMIN <= r && r <= Thearch.REGMAX,
792 Thearch.FREGMIN <= r && r <= Thearch.FREGMAX:
795 Fatalf("reginuse: reg out of range")
798 return reg[r-Thearch.REGMIN] > 0
801 // Regrealloc(n) undoes the effect of Regfree(n),
802 // so that a register can be given up but then reclaimed.
803 func Regrealloc(n *Node) {
804 if n.Op != OREGISTER && n.Op != OINDREG {
805 Fatalf("regrealloc: not a register")
808 if i == Thearch.REGSP {
812 case Thearch.REGMIN <= i && i <= Thearch.REGMAX,
813 Thearch.FREGMIN <= i && i <= Thearch.FREGMAX:
816 Fatalf("regrealloc: reg out of range")
820 if reg[i] == 0 && Debug['v'] > 0 {
821 if regstk[i] == nil {
822 regstk[i] = make([]byte, 4096)
825 n := runtime.Stack(stk[:cap(stk)], false)
833 fmt.Printf("run compiler with -v for register allocation sites\n")
837 dump := func(r int) {
838 stk := regstk[r-Thearch.REGMIN]
842 fmt.Printf("reg %v allocated at:\n", obj.Rconv(r))
843 fmt.Printf("\t%s\n", strings.Replace(strings.TrimSpace(string(stk)), "\n", "\n\t", -1))
846 for r := Thearch.REGMIN; r <= Thearch.REGMAX; r++ {
847 if reg[r-Thearch.REGMIN] != 0 {
851 for r := Thearch.FREGMIN; r <= Thearch.FREGMAX; r++ {
852 if reg[r-Thearch.REGMIN] == 0 {