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-rw-r--r--src/cmd/8g/peep.c890
1 files changed, 0 insertions, 890 deletions
diff --git a/src/cmd/8g/peep.c b/src/cmd/8g/peep.c
deleted file mode 100644
index 5ad29e1b2..000000000
--- a/src/cmd/8g/peep.c
+++ /dev/null
@@ -1,890 +0,0 @@
-// Derived from Inferno utils/6c/peep.c
-// http://code.google.com/p/inferno-os/source/browse/utils/6c/peep.c
-//
-// 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.
-
-#include "gg.h"
-#include "opt.h"
-
-#define REGEXT 0
-
-static void conprop(Reg *r);
-
-// do we need the carry bit
-static int
-needc(Prog *p)
-{
- while(p != P) {
- switch(p->as) {
- case AADCL:
- case ASBBL:
- case ARCRL:
- return 1;
- case AADDL:
- case ASUBL:
- case AJMP:
- case ARET:
- case ACALL:
- return 0;
- default:
- if(p->to.type == D_BRANCH)
- return 0;
- }
- p = p->link;
- }
- return 0;
-}
-
-static Reg*
-rnops(Reg *r)
-{
- Prog *p;
- Reg *r1;
-
- if(r != R)
- for(;;) {
- p = r->prog;
- if(p->as != ANOP || p->from.type != D_NONE || p->to.type != D_NONE)
- break;
- r1 = uniqs(r);
- if(r1 == R)
- break;
- r = r1;
- }
- return r;
-}
-
-void
-peep(void)
-{
- Reg *r, *r1, *r2;
- Prog *p, *p1;
- int t;
-
- /*
- * complete R structure
- */
- t = 0;
- for(r=firstr; r!=R; r=r1) {
- r1 = r->link;
- if(r1 == R)
- break;
- p = r->prog->link;
- while(p != r1->prog)
- switch(p->as) {
- default:
- r2 = rega();
- r->link = r2;
- r2->link = r1;
-
- r2->prog = p;
- p->reg = r2;
-
- r2->p1 = r;
- r->s1 = r2;
- r2->s1 = r1;
- r1->p1 = r2;
-
- r = r2;
- t++;
-
- case ADATA:
- case AGLOBL:
- case ANAME:
- case ASIGNAME:
- p = p->link;
- }
- }
-
- // movb elimination.
- // movb is simulated by the linker
- // when a register other than ax, bx, cx, dx
- // is used, so rewrite to other instructions
- // when possible. a movb into a register
- // can smash the entire 32-bit register without
- // causing any trouble.
- for(r=firstr; r!=R; r=r->link) {
- p = r->prog;
- if(p->as == AMOVB && regtyp(&p->to)) {
- // movb into register.
- // from another register or constant can be movl.
- if(regtyp(&p->from) || p->from.type == D_CONST)
- p->as = AMOVL;
- else
- p->as = AMOVBLZX;
- }
- }
-
- // constant propagation
- // find MOV $con,R followed by
- // another MOV $con,R without
- // setting R in the interim
- for(r=firstr; r!=R; r=r->link) {
- p = r->prog;
- switch(p->as) {
- case ALEAL:
- if(regtyp(&p->to))
- if(p->from.sym != S)
- conprop(r);
- break;
-
- case AMOVB:
- case AMOVW:
- case AMOVL:
- if(regtyp(&p->to))
- if(p->from.type == D_CONST)
- conprop(r);
- break;
- }
- }
-
-loop1:
- if(debug['P'] && debug['v'])
- dumpit("loop1", firstr);
-
- t = 0;
- for(r=firstr; r!=R; r=r->link) {
- p = r->prog;
- switch(p->as) {
- case AMOVB:
- case AMOVW:
- case AMOVL:
- if(regtyp(&p->to))
- if(regtyp(&p->from)) {
- if(copyprop(r)) {
- excise(r);
- t++;
- } else
- if(subprop(r) && copyprop(r)) {
- excise(r);
- t++;
- }
- }
- break;
-
- case AMOVBLZX:
- case AMOVWLZX:
- case AMOVBLSX:
- case AMOVWLSX:
- if(regtyp(&p->to)) {
- r1 = rnops(uniqs(r));
- if(r1 != R) {
- p1 = r1->prog;
- if(p->as == p1->as && p->to.type == p1->from.type){
- p1->as = AMOVL;
- t++;
- }
- }
- }
- break;
-
- case AADDB:
- case AADDL:
- case AADDW:
- if(p->from.type != D_CONST || needc(p->link))
- break;
- if(p->from.offset == -1){
- if(p->as == AADDL)
- p->as = ADECL;
- else
- p->as = ADECW;
- p->from = zprog.from;
- break;
- }
- if(p->from.offset == 1){
- if(p->as == AADDL)
- p->as = AINCL;
- else
- p->as = AINCW;
- p->from = zprog.from;
- break;
- }
- break;
-
- case ASUBB:
- case ASUBL:
- case ASUBW:
- if(p->from.type != D_CONST || needc(p->link))
- break;
- if(p->from.offset == -1) {
- if(p->as == ASUBL)
- p->as = AINCL;
- else
- p->as = AINCW;
- p->from = zprog.from;
- break;
- }
- if(p->from.offset == 1){
- if(p->as == ASUBL)
- p->as = ADECL;
- else
- p->as = ADECW;
- p->from = zprog.from;
- break;
- }
- break;
- }
- }
- if(t)
- goto loop1;
-}
-
-void
-excise(Reg *r)
-{
- Prog *p;
-
- p = r->prog;
- if(debug['P'] && debug['v'])
- print("%P ===delete===\n", p);
-
- p->as = ANOP;
- p->from = zprog.from;
- p->to = zprog.to;
-
- ostats.ndelmov++;
-}
-
-Reg*
-uniqp(Reg *r)
-{
- Reg *r1;
-
- r1 = r->p1;
- if(r1 == R) {
- r1 = r->p2;
- if(r1 == R || r1->p2link != R)
- return R;
- } else
- if(r->p2 != R)
- return R;
- return r1;
-}
-
-Reg*
-uniqs(Reg *r)
-{
- Reg *r1;
-
- r1 = r->s1;
- if(r1 == R) {
- r1 = r->s2;
- if(r1 == R)
- return R;
- } else
- if(r->s2 != R)
- return R;
- return r1;
-}
-
-int
-regtyp(Adr *a)
-{
- int t;
-
- t = a->type;
- if(t >= D_AX && t <= D_DI)
- return 1;
- return 0;
-}
-
-/*
- * the idea is to substitute
- * one register for another
- * from one MOV to another
- * MOV a, R0
- * ADD b, R0 / no use of R1
- * MOV R0, R1
- * would be converted to
- * MOV a, R1
- * ADD b, R1
- * MOV R1, R0
- * hopefully, then the former or latter MOV
- * will be eliminated by copy propagation.
- */
-int
-subprop(Reg *r0)
-{
- Prog *p;
- Adr *v1, *v2;
- Reg *r;
- int t;
-
- p = r0->prog;
- v1 = &p->from;
- if(!regtyp(v1))
- return 0;
- v2 = &p->to;
- if(!regtyp(v2))
- return 0;
- for(r=uniqp(r0); r!=R; r=uniqp(r)) {
- if(uniqs(r) == R)
- break;
- p = r->prog;
- switch(p->as) {
- case ACALL:
- return 0;
-
- case AIMULL:
- case AIMULW:
- if(p->to.type != D_NONE)
- break;
-
- case ADIVB:
- case ADIVL:
- case ADIVW:
- case AIDIVB:
- case AIDIVL:
- case AIDIVW:
- case AIMULB:
- case AMULB:
- case AMULL:
- case AMULW:
-
- case ARCLB:
- case ARCLL:
- case ARCLW:
- case ARCRB:
- case ARCRL:
- case ARCRW:
- case AROLB:
- case AROLL:
- case AROLW:
- case ARORB:
- case ARORL:
- case ARORW:
- case ASALB:
- case ASALL:
- case ASALW:
- case ASARB:
- case ASARL:
- case ASARW:
- case ASHLB:
- case ASHLL:
- case ASHLW:
- case ASHRB:
- case ASHRL:
- case ASHRW:
-
- case AREP:
- case AREPN:
-
- case ACWD:
- case ACDQ:
-
- case ASTOSB:
- case ASTOSL:
- case AMOVSB:
- case AMOVSL:
- return 0;
-
- case AMOVB:
- case AMOVW:
- case AMOVL:
- if(p->to.type == v1->type)
- goto gotit;
- break;
- }
- if(copyau(&p->from, v2) ||
- copyau(&p->to, v2))
- break;
- if(copysub(&p->from, v1, v2, 0) ||
- copysub(&p->to, v1, v2, 0))
- break;
- }
- return 0;
-
-gotit:
- copysub(&p->to, v1, v2, 1);
- if(debug['P']) {
- print("gotit: %D->%D\n%P", v1, v2, r->prog);
- if(p->from.type == v2->type)
- print(" excise");
- print("\n");
- }
- for(r=uniqs(r); r!=r0; r=uniqs(r)) {
- p = r->prog;
- copysub(&p->from, v1, v2, 1);
- copysub(&p->to, v1, v2, 1);
- if(debug['P'])
- print("%P\n", r->prog);
- }
- t = v1->type;
- v1->type = v2->type;
- v2->type = t;
- if(debug['P'])
- print("%P last\n", r->prog);
- return 1;
-}
-
-/*
- * The idea is to remove redundant copies.
- * v1->v2 F=0
- * (use v2 s/v2/v1/)*
- * set v1 F=1
- * use v2 return fail
- * -----------------
- * v1->v2 F=0
- * (use v2 s/v2/v1/)*
- * set v1 F=1
- * set v2 return success
- */
-int
-copyprop(Reg *r0)
-{
- Prog *p;
- Adr *v1, *v2;
- Reg *r;
-
- p = r0->prog;
- v1 = &p->from;
- v2 = &p->to;
- if(copyas(v1, v2))
- return 1;
- for(r=firstr; r!=R; r=r->link)
- r->active = 0;
- return copy1(v1, v2, r0->s1, 0);
-}
-
-int
-copy1(Adr *v1, Adr *v2, Reg *r, int f)
-{
- int t;
- Prog *p;
-
- if(r->active) {
- if(debug['P'])
- print("act set; return 1\n");
- return 1;
- }
- r->active = 1;
- if(debug['P'])
- print("copy %D->%D f=%d\n", v1, v2, f);
- for(; r != R; r = r->s1) {
- p = r->prog;
- if(debug['P'])
- print("%P", p);
- if(!f && uniqp(r) == R) {
- f = 1;
- if(debug['P'])
- print("; merge; f=%d", f);
- }
- t = copyu(p, v2, A);
- switch(t) {
- case 2: /* rar, cant split */
- if(debug['P'])
- print("; %D rar; return 0\n", v2);
- return 0;
-
- case 3: /* set */
- if(debug['P'])
- print("; %D set; return 1\n", v2);
- return 1;
-
- case 1: /* used, substitute */
- case 4: /* use and set */
- if(f) {
- if(!debug['P'])
- return 0;
- if(t == 4)
- print("; %D used+set and f=%d; return 0\n", v2, f);
- else
- print("; %D used and f=%d; return 0\n", v2, f);
- return 0;
- }
- if(copyu(p, v2, v1)) {
- if(debug['P'])
- print("; sub fail; return 0\n");
- return 0;
- }
- if(debug['P'])
- print("; sub %D/%D", v2, v1);
- if(t == 4) {
- if(debug['P'])
- print("; %D used+set; return 1\n", v2);
- return 1;
- }
- break;
- }
- if(!f) {
- t = copyu(p, v1, A);
- if(!f && (t == 2 || t == 3 || t == 4)) {
- f = 1;
- if(debug['P'])
- print("; %D set and !f; f=%d", v1, f);
- }
- }
- if(debug['P'])
- print("\n");
- if(r->s2)
- if(!copy1(v1, v2, r->s2, f))
- return 0;
- }
- return 1;
-}
-
-/*
- * return
- * 1 if v only used (and substitute),
- * 2 if read-alter-rewrite
- * 3 if set
- * 4 if set and used
- * 0 otherwise (not touched)
- */
-int
-copyu(Prog *p, Adr *v, Adr *s)
-{
-
- switch(p->as) {
-
- default:
- if(debug['P'])
- print("unknown op %A\n", p->as);
- /* SBBL; ADCL; FLD1; SAHF */
- return 2;
-
-
- case ANEGB:
- case ANEGW:
- case ANEGL:
- case ANOTB:
- case ANOTW:
- case ANOTL:
- if(copyas(&p->to, v))
- return 2;
- break;
-
- case ALEAL: /* lhs addr, rhs store */
- if(copyas(&p->from, v))
- return 2;
-
-
- case ANOP: /* rhs store */
- case AMOVB:
- case AMOVW:
- case AMOVL:
- case AMOVBLSX:
- case AMOVBLZX:
- case AMOVWLSX:
- case AMOVWLZX:
- if(copyas(&p->to, v)) {
- if(s != A)
- return copysub(&p->from, v, s, 1);
- if(copyau(&p->from, v))
- return 4;
- return 3;
- }
- goto caseread;
-
- case ARCLB:
- case ARCLL:
- case ARCLW:
- case ARCRB:
- case ARCRL:
- case ARCRW:
- case AROLB:
- case AROLL:
- case AROLW:
- case ARORB:
- case ARORL:
- case ARORW:
- case ASALB:
- case ASALL:
- case ASALW:
- case ASARB:
- case ASARL:
- case ASARW:
- case ASHLB:
- case ASHLL:
- case ASHLW:
- case ASHRB:
- case ASHRL:
- case ASHRW:
- if(copyas(&p->to, v))
- return 2;
- if(copyas(&p->from, v))
- if(p->from.type == D_CX)
- return 2;
- goto caseread;
-
- case AADDB: /* rhs rar */
- case AADDL:
- case AADDW:
- case AANDB:
- case AANDL:
- case AANDW:
- case ADECL:
- case ADECW:
- case AINCL:
- case AINCW:
- case ASUBB:
- case ASUBL:
- case ASUBW:
- case AORB:
- case AORL:
- case AORW:
- case AXORB:
- case AXORL:
- case AXORW:
- if(copyas(&p->to, v))
- return 2;
- goto caseread;
-
- case ACMPL: /* read only */
- case ACMPW:
- case ACMPB:
- caseread:
- if(s != A) {
- if(copysub(&p->from, v, s, 1))
- return 1;
- return copysub(&p->to, v, s, 1);
- }
- if(copyau(&p->from, v))
- return 1;
- if(copyau(&p->to, v))
- return 1;
- break;
-
- case AJGE: /* no reference */
- case AJNE:
- case AJLE:
- case AJEQ:
- case AJHI:
- case AJLS:
- case AJMI:
- case AJPL:
- case AJGT:
- case AJLT:
- case AJCC:
- case AJCS:
-
- case AADJSP:
- case AWAIT:
- case ACLD:
- break;
-
- case AIMULL:
- case AIMULW:
- if(p->to.type != D_NONE) {
- if(copyas(&p->to, v))
- return 2;
- goto caseread;
- }
-
- case ADIVB:
- case ADIVL:
- case ADIVW:
- case AIDIVB:
- case AIDIVL:
- case AIDIVW:
- case AIMULB:
- case AMULB:
- case AMULL:
- case AMULW:
-
- case ACWD:
- case ACDQ:
- if(v->type == D_AX || v->type == D_DX)
- return 2;
- goto caseread;
-
- case AREP:
- case AREPN:
- if(v->type == D_CX)
- return 2;
- goto caseread;
-
- case AMOVSB:
- case AMOVSL:
- if(v->type == D_DI || v->type == D_SI)
- return 2;
- goto caseread;
-
- case ASTOSB:
- case ASTOSL:
- if(v->type == D_AX || v->type == D_DI)
- return 2;
- goto caseread;
-
- case AJMP: /* funny */
- if(s != A) {
- if(copysub(&p->to, v, s, 1))
- return 1;
- return 0;
- }
- if(copyau(&p->to, v))
- return 1;
- return 0;
-
- case ARET: /* funny */
- if(v->type == REGRET || v->type == FREGRET)
- return 2;
- if(s != A)
- return 1;
- return 3;
-
- case ACALL: /* funny */
- if(REGEXT && v->type <= REGEXT && v->type > exregoffset)
- return 2;
- if(REGARG >= 0 && v->type == (uchar)REGARG)
- return 2;
-
- if(s != A) {
- if(copysub(&p->to, v, s, 1))
- return 1;
- return 0;
- }
- if(copyau(&p->to, v))
- return 4;
- return 3;
-
- case ATEXT: /* funny */
- if(REGARG >= 0 && v->type == (uchar)REGARG)
- return 3;
- return 0;
- }
- return 0;
-}
-
-/*
- * direct reference,
- * could be set/use depending on
- * semantics
- */
-int
-copyas(Adr *a, Adr *v)
-{
- if(a->type != v->type)
- return 0;
- if(regtyp(v))
- return 1;
- if(v->type == D_AUTO || v->type == D_PARAM)
- if(v->offset == a->offset)
- return 1;
- return 0;
-}
-
-/*
- * either direct or indirect
- */
-int
-copyau(Adr *a, Adr *v)
-{
-
- if(copyas(a, v))
- return 1;
- if(regtyp(v)) {
- if(a->type-D_INDIR == v->type)
- return 1;
- if(a->index == v->type)
- return 1;
- }
- return 0;
-}
-
-/*
- * substitute s for v in a
- * return failure to substitute
- */
-int
-copysub(Adr *a, Adr *v, Adr *s, int f)
-{
- int t;
-
- if(copyas(a, v)) {
- t = s->type;
- if(t >= D_AX && t <= D_DI) {
- if(f)
- a->type = t;
- }
- return 0;
- }
- if(regtyp(v)) {
- t = v->type;
- if(a->type == t+D_INDIR) {
- if((s->type == D_BP) && a->index != D_NONE)
- return 1; /* can't use BP-base with index */
- if(f)
- a->type = s->type+D_INDIR;
-// return 0;
- }
- if(a->index == t) {
- if(f)
- a->index = s->type;
- return 0;
- }
- return 0;
- }
- return 0;
-}
-
-static void
-conprop(Reg *r0)
-{
- Reg *r;
- Prog *p, *p0;
- int t;
- Adr *v0;
-
- p0 = r0->prog;
- v0 = &p0->to;
- r = r0;
-
-loop:
- r = uniqs(r);
- if(r == R || r == r0)
- return;
- if(uniqp(r) == R)
- return;
-
- p = r->prog;
- t = copyu(p, v0, A);
- switch(t) {
- case 0: // miss
- case 1: // use
- goto loop;
-
- case 2: // rar
- case 4: // use and set
- break;
-
- case 3: // set
- if(p->as == p0->as)
- if(p->from.type == p0->from.type)
- if(p->from.sym == p0->from.sym)
- if(p->from.offset == p0->from.offset)
- if(p->from.scale == p0->from.scale)
- if(p->from.dval == p0->from.dval)
- if(p->from.index == p0->from.index) {
- excise(r);
- t++;
- goto loop;
- }
- break;
- }
-}
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