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-rw-r--r--src/cmd/9c/peep.c1076
1 files changed, 1076 insertions, 0 deletions
diff --git a/src/cmd/9c/peep.c b/src/cmd/9c/peep.c
new file mode 100644
index 000000000..2e8e2adcc
--- /dev/null
+++ b/src/cmd/9c/peep.c
@@ -0,0 +1,1076 @@
+// cmd/9c/peep.c from Vita Nuova.
+//
+// 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 © 2000-2008 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 © 2000-2008 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 "gc.h"
+
+/*
+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;
+ 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;
+ }
+ }
+
+loop1:
+ t = 0;
+ for(r=firstr; r!=R; r=r->link) {
+ p = r->prog;
+ if(p->as == AMOVW || p->as == AMOVD || p->as == AFMOVS || p->as == AFMOVD)
+ if(regtyp(&p->to)) {
+ if(regtyp(&p->from))
+ if(p->from.type == p->to.type) {
+ if(copyprop(r)) {
+ excise(r);
+ t++;
+ } else
+ if(subprop(r) && copyprop(r)) {
+ excise(r);
+ t++;
+ }
+ }
+ if(regzer(&p->from))
+ if(p->to.type == D_REG) {
+ p->from.type = D_REG;
+ p->from.reg = REGZERO;
+ if(copyprop(r)) {
+ excise(r);
+ t++;
+ } else
+ if(subprop(r) && copyprop(r)) {
+ excise(r);
+ t++;
+ }
+ }
+ }
+ }
+ if(t)
+ goto loop1;
+ /*
+ * look for MOVB x,R; MOVB R,R
+ */
+ for(r=firstr; r!=R; r=r->link) {
+ p = r->prog;
+ switch(p->as) {
+ default:
+ continue;
+ case AMOVH:
+ case AMOVHZ:
+ case AMOVB:
+ case AMOVBZ:
+ case AMOVW:
+ case AMOVWZ:
+ if(p->to.type != D_REG)
+ continue;
+ break;
+ }
+ r1 = r->link;
+ if(r1 == R)
+ continue;
+ p1 = r1->prog;
+ if(p1->as != p->as)
+ continue;
+ if(p1->from.type != D_REG || p1->from.reg != p->to.reg)
+ continue;
+ if(p1->to.type != D_REG || p1->to.reg != p->to.reg)
+ continue;
+ excise(r1);
+ }
+
+ if(debug['D'] > 1)
+ return; /* allow following code improvement to be suppressed */
+
+ /*
+ * look for OP x,y,R; CMP R, $0 -> OPCC x,y,R
+ * when OP can set condition codes correctly
+ */
+ for(r=firstr; r!=R; r=r->link) {
+ p = r->prog;
+ switch(p->as) {
+ case ACMP:
+ case ACMPW: /* always safe? */
+ if(!regzer(&p->to))
+ continue;
+ r1 = r->s1;
+ if(r1 == R)
+ continue;
+ switch(r1->prog->as) {
+ default:
+ continue;
+ case ABCL:
+ case ABC:
+ /* the conditions can be complex and these are currently little used */
+ continue;
+ case ABEQ:
+ case ABGE:
+ case ABGT:
+ case ABLE:
+ case ABLT:
+ case ABNE:
+ case ABVC:
+ case ABVS:
+ break;
+ }
+ r1 = r;
+ do
+ r1 = uniqp(r1);
+ while (r1 != R && r1->prog->as == ANOP);
+ if(r1 == R)
+ continue;
+ p1 = r1->prog;
+ if(p1->to.type != D_REG || p1->to.reg != p->from.reg)
+ continue;
+ switch(p1->as) {
+ case ASUB:
+ case AADD:
+ case AXOR:
+ case AOR:
+ /* irregular instructions */
+ if(p1->from.type == D_CONST)
+ continue;
+ break;
+ }
+ switch(p1->as) {
+ default:
+ continue;
+ case AMOVW:
+ case AMOVD:
+ if(p1->from.type != D_REG)
+ continue;
+ continue;
+ case AANDCC:
+ case AANDNCC:
+ case AORCC:
+ case AORNCC:
+ case AXORCC:
+ case ASUBCC:
+ case ASUBECC:
+ case ASUBMECC:
+ case ASUBZECC:
+ case AADDCC:
+ case AADDCCC:
+ case AADDECC:
+ case AADDMECC:
+ case AADDZECC:
+ case ARLWMICC:
+ case ARLWNMCC:
+ t = p1->as;
+ break;
+ /* don't deal with floating point instructions for now */
+/*
+ case AFABS: t = AFABSCC; break;
+ case AFADD: t = AFADDCC; break;
+ case AFADDS: t = AFADDSCC; break;
+ case AFCTIW: t = AFCTIWCC; break;
+ case AFCTIWZ: t = AFCTIWZCC; break;
+ case AFDIV: t = AFDIVCC; break;
+ case AFDIVS: t = AFDIVSCC; break;
+ case AFMADD: t = AFMADDCC; break;
+ case AFMADDS: t = AFMADDSCC; break;
+ case AFMOVD: t = AFMOVDCC; break;
+ case AFMSUB: t = AFMSUBCC; break;
+ case AFMSUBS: t = AFMSUBSCC; break;
+ case AFMUL: t = AFMULCC; break;
+ case AFMULS: t = AFMULSCC; break;
+ case AFNABS: t = AFNABSCC; break;
+ case AFNEG: t = AFNEGCC; break;
+ case AFNMADD: t = AFNMADDCC; break;
+ case AFNMADDS: t = AFNMADDSCC; break;
+ case AFNMSUB: t = AFNMSUBCC; break;
+ case AFNMSUBS: t = AFNMSUBSCC; break;
+ case AFRSP: t = AFRSPCC; break;
+ case AFSUB: t = AFSUBCC; break;
+ case AFSUBS: t = AFSUBSCC; break;
+ case ACNTLZW: t = ACNTLZWCC; break;
+ case AMTFSB0: t = AMTFSB0CC; break;
+ case AMTFSB1: t = AMTFSB1CC; break;
+*/
+ case AADD: t = AADDCC; break;
+ case AADDV: t = AADDVCC; break;
+ case AADDC: t = AADDCCC; break;
+ case AADDCV: t = AADDCVCC; break;
+ case AADDME: t = AADDMECC; break;
+ case AADDMEV: t = AADDMEVCC; break;
+ case AADDE: t = AADDECC; break;
+ case AADDEV: t = AADDEVCC; break;
+ case AADDZE: t = AADDZECC; break;
+ case AADDZEV: t = AADDZEVCC; break;
+ case AAND: t = AANDCC; break;
+ case AANDN: t = AANDNCC; break;
+ case ADIVW: t = ADIVWCC; break;
+ case ADIVWV: t = ADIVWVCC; break;
+ case ADIVWU: t = ADIVWUCC; break;
+ case ADIVWUV: t = ADIVWUVCC; break;
+ case ADIVD: t = ADIVDCC; break;
+ case ADIVDV: t = ADIVDVCC; break;
+ case ADIVDU: t = ADIVDUCC; break;
+ case ADIVDUV: t = ADIVDUVCC; break;
+ case AEQV: t = AEQVCC; break;
+ case AEXTSB: t = AEXTSBCC; break;
+ case AEXTSH: t = AEXTSHCC; break;
+ case AEXTSW: t = AEXTSWCC; break;
+ case AMULHW: t = AMULHWCC; break;
+ case AMULHWU: t = AMULHWUCC; break;
+ case AMULLW: t = AMULLWCC; break;
+ case AMULLWV: t = AMULLWVCC; break;
+ case AMULHD: t = AMULHDCC; break;
+ case AMULHDU: t = AMULHDUCC; break;
+ case AMULLD: t = AMULLDCC; break;
+ case AMULLDV: t = AMULLDVCC; break;
+ case ANAND: t = ANANDCC; break;
+ case ANEG: t = ANEGCC; break;
+ case ANEGV: t = ANEGVCC; break;
+ case ANOR: t = ANORCC; break;
+ case AOR: t = AORCC; break;
+ case AORN: t = AORNCC; break;
+ case AREM: t = AREMCC; break;
+ case AREMV: t = AREMVCC; break;
+ case AREMU: t = AREMUCC; break;
+ case AREMUV: t = AREMUVCC; break;
+ case AREMD: t = AREMDCC; break;
+ case AREMDV: t = AREMDVCC; break;
+ case AREMDU: t = AREMDUCC; break;
+ case AREMDUV: t = AREMDUVCC; break;
+ case ARLWMI: t = ARLWMICC; break;
+ case ARLWNM: t = ARLWNMCC; break;
+ case ASLW: t = ASLWCC; break;
+ case ASRAW: t = ASRAWCC; break;
+ case ASRW: t = ASRWCC; break;
+ case ASLD: t = ASLDCC; break;
+ case ASRAD: t = ASRADCC; break;
+ case ASRD: t = ASRDCC; break;
+ case ASUB: t = ASUBCC; break;
+ case ASUBV: t = ASUBVCC; break;
+ case ASUBC: t = ASUBCCC; break;
+ case ASUBCV: t = ASUBCVCC; break;
+ case ASUBME: t = ASUBMECC; break;
+ case ASUBMEV: t = ASUBMEVCC; break;
+ case ASUBE: t = ASUBECC; break;
+ case ASUBEV: t = ASUBEVCC; break;
+ case ASUBZE: t = ASUBZECC; break;
+ case ASUBZEV: t = ASUBZEVCC; break;
+ case AXOR: t = AXORCC; break;
+ break;
+ }
+ if(debug['D'])
+ print("cmp %P; %P -> ", p1, p);
+ p1->as = t;
+ if(debug['D'])
+ print("%P\n", p1);
+ excise(r);
+ continue;
+ }
+ }
+}
+
+void
+excise(Reg *r)
+{
+ Prog *p;
+
+ p = r->prog;
+ p->as = ANOP;
+ p->from = zprog.from;
+ p->from3 = zprog.from3;
+ p->to = zprog.to;
+ p->reg = zprog.reg; /**/
+}
+
+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;
+}
+
+/*
+ * if the system forces R0 to be zero,
+ * convert references to $0 to references to R0.
+ */
+int
+regzer(Addr *a)
+{
+ if(R0ISZERO) {
+ if(a->type == D_CONST)
+ if(a->sym == nil)
+ if(a->offset == 0)
+ return 1;
+ if(a->type == D_REG)
+ if(a->reg == REGZERO)
+ return 1;
+ }
+ return 0;
+}
+
+int
+regtyp(Addr *a)
+{
+
+ if(a->type == D_REG) {
+ if(!R0ISZERO || a->reg != REGZERO)
+ return 1;
+ return 0;
+ }
+ if(a->type == D_FREG)
+ 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;
+ Addr *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 ABL:
+ return 0;
+
+ case AADD:
+ case AADDC:
+ case AADDCC:
+ case AADDE:
+ case AADDECC:
+ case ASUB:
+ case ASUBCC:
+ case ASUBC:
+ case ASUBCCC:
+ case ASUBE:
+ case ASUBECC:
+ case ASLW:
+ case ASRW:
+ case ASRWCC:
+ case ASRAW:
+ case ASRAWCC:
+ case ASLD:
+ case ASRD:
+ case ASRAD:
+ case AOR:
+ case AORCC:
+ case AORN:
+ case AORNCC:
+ case AAND:
+ case AANDCC:
+ case AANDN:
+ case AANDNCC:
+ case ANAND:
+ case ANANDCC:
+ case ANOR:
+ case ANORCC:
+ case AXOR:
+ case AXORCC:
+ case AMULHW:
+ case AMULHWU:
+ case AMULLW:
+ case AMULLD:
+ case ADIVW:
+ case ADIVWU:
+ case ADIVD:
+ case ADIVDU:
+ case AREM:
+ case AREMU:
+ case AREMD:
+ case AREMDU:
+ case ARLWNM:
+ case ARLWNMCC:
+
+ case AFADD:
+ case AFADDS:
+ case AFSUB:
+ case AFSUBS:
+ case AFMUL:
+ case AFMULS:
+ case AFDIV:
+ case AFDIVS:
+ if(p->to.type == v1->type)
+ if(p->to.reg == v1->reg) {
+ if(p->reg == NREG)
+ p->reg = p->to.reg;
+ goto gotit;
+ }
+ break;
+
+ case AADDME:
+ case AADDMECC:
+ case AADDZE:
+ case AADDZECC:
+ case ASUBME:
+ case ASUBMECC:
+ case ASUBZE:
+ case ASUBZECC:
+ case ANEG:
+ case ANEGCC:
+ case AFNEG:
+ case AFNEGCC:
+ case AFMOVS:
+ case AFMOVD:
+ case AMOVW:
+ case AMOVD:
+ if(p->to.type == v1->type)
+ if(p->to.reg == v1->reg)
+ goto gotit;
+ break;
+ }
+ if(copyau(&p->from, v2) ||
+ copyau1(p, v2) ||
+ copyau(&p->to, v2))
+ break;
+ if(copysub(&p->from, v1, v2, 0) ||
+ copysub1(p, 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);
+ copysub1(p, v1, v2, 1);
+ copysub(&p->to, v1, v2, 1);
+ if(debug['P'])
+ print("%P\n", r->prog);
+ }
+ t = v1->reg;
+ v1->reg = v2->reg;
+ v2->reg = 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;
+ Addr *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(Addr *v1, Addr *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, nil);
+ switch(t) {
+ case 2: /* rar, cant split */
+ if(debug['P'])
+ print("; %Drar; return 0\n", v2);
+ return 0;
+
+ case 3: /* set */
+ if(debug['P'])
+ print("; %Dset; 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("; %Dused+set and f=%d; return 0\n", v2, f);
+ else
+ print("; %Dused 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("; %Dused+set; return 1\n", v2);
+ return 1;
+ }
+ break;
+ }
+ if(!f) {
+ t = copyu(p, v1, nil);
+ if(!f && (t == 2 || t == 3 || t == 4)) {
+ f = 1;
+ if(debug['P'])
+ print("; %Dset 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, Addr *v, Addr *s)
+{
+
+ switch(p->as) {
+
+ default:
+ if(debug['P'])
+ print(" (\?\?\?)");
+ return 2;
+
+
+ case ANOP: /* read, write */
+ case AMOVH:
+ case AMOVHZ:
+ case AMOVB:
+ case AMOVBZ:
+ case AMOVW:
+ case AMOVWZ:
+ case AMOVD:
+
+ case ANEG:
+ case ANEGCC:
+ case AADDME:
+ case AADDMECC:
+ case AADDZE:
+ case AADDZECC:
+ case ASUBME:
+ case ASUBMECC:
+ case ASUBZE:
+ case ASUBZECC:
+
+ case AFCTIW:
+ case AFCTIWZ:
+ case AFMOVS:
+ case AFMOVD:
+ case AFRSP:
+ case AFNEG:
+ case AFNEGCC:
+ if(s != nil) {
+ if(copysub(&p->from, v, s, 1))
+ return 1;
+ if(!copyas(&p->to, v))
+ if(copysub(&p->to, v, s, 1))
+ return 1;
+ return 0;
+ }
+ if(copyas(&p->to, v)) {
+ if(copyau(&p->from, v))
+ return 4;
+ return 3;
+ }
+ if(copyau(&p->from, v))
+ return 1;
+ if(copyau(&p->to, v))
+ return 1;
+ return 0;
+
+ case ARLWMI: /* read read rar */
+ case ARLWMICC:
+ if(copyas(&p->to, v))
+ return 2;
+ /* fall through */
+
+ case AADD: /* read read write */
+ case AADDC:
+ case AADDE:
+ case ASUB:
+ case ASLW:
+ case ASRW:
+ case ASRAW:
+ case ASLD:
+ case ASRD:
+ case ASRAD:
+ case AOR:
+ case AORCC:
+ case AORN:
+ case AORNCC:
+ case AAND:
+ case AANDCC:
+ case AANDN:
+ case AANDNCC:
+ case ANAND:
+ case ANANDCC:
+ case ANOR:
+ case ANORCC:
+ case AXOR:
+ case AMULHW:
+ case AMULHWU:
+ case AMULLW:
+ case AMULLD:
+ case ADIVW:
+ case ADIVD:
+ case ADIVWU:
+ case ADIVDU:
+ case AREM:
+ case AREMU:
+ case AREMD:
+ case AREMDU:
+ case ARLWNM:
+ case ARLWNMCC:
+
+ case AFADDS:
+ case AFADD:
+ case AFSUBS:
+ case AFSUB:
+ case AFMULS:
+ case AFMUL:
+ case AFDIVS:
+ case AFDIV:
+ if(s != nil) {
+ if(copysub(&p->from, v, s, 1))
+ return 1;
+ if(copysub1(p, v, s, 1))
+ return 1;
+ if(!copyas(&p->to, v))
+ if(copysub(&p->to, v, s, 1))
+ return 1;
+ return 0;
+ }
+ if(copyas(&p->to, v)) {
+ if(p->reg == NREG)
+ p->reg = p->to.reg;
+ if(copyau(&p->from, v))
+ return 4;
+ if(copyau1(p, v))
+ return 4;
+ return 3;
+ }
+ if(copyau(&p->from, v))
+ return 1;
+ if(copyau1(p, v))
+ return 1;
+ if(copyau(&p->to, v))
+ return 1;
+ return 0;
+
+ case ABEQ:
+ case ABGT:
+ case ABGE:
+ case ABLT:
+ case ABLE:
+ case ABNE:
+ case ABVC:
+ case ABVS:
+ break;
+
+ case ACMP: /* read read */
+ case ACMPU:
+ case ACMPW:
+ case ACMPWU:
+ case AFCMPO:
+ case AFCMPU:
+ if(s != nil) {
+ 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 ABR: /* funny */
+ if(s != nil) {
+ if(copysub(&p->to, v, s, 1))
+ return 1;
+ return 0;
+ }
+ if(copyau(&p->to, v))
+ return 1;
+ return 0;
+
+ case ARETURN: /* funny */
+ if(v->type == D_REG)
+ if(v->reg == REGRET)
+ return 2;
+ if(v->type == D_FREG)
+ if(v->reg == FREGRET)
+ return 2;
+
+ case ABL: /* funny */
+ if(v->type == D_REG) {
+ if(v->reg <= REGEXT && v->reg > exregoffset)
+ return 2;
+ if(v->reg == REGARG)
+ return 2;
+ }
+ if(v->type == D_FREG) {
+ if(v->reg <= FREGEXT && v->reg > exfregoffset)
+ return 2;
+ }
+
+ if(s != nil) {
+ if(copysub(&p->to, v, s, 1))
+ return 1;
+ return 0;
+ }
+ if(copyau(&p->to, v))
+ return 4;
+ return 3;
+
+ case ATEXT: /* funny */
+ if(v->type == D_REG)
+ if(v->reg == REGARG)
+ return 3;
+ return 0;
+ }
+ return 0;
+}
+
+int
+a2type(Prog *p)
+{
+
+ switch(p->as) {
+ case AADD:
+ case AADDC:
+ case AADDCC:
+ case AADDCCC:
+ case AADDE:
+ case AADDECC:
+ case AADDME:
+ case AADDMECC:
+ case AADDZE:
+ case AADDZECC:
+ case ASUB:
+ case ASUBC:
+ case ASUBCC:
+ case ASUBCCC:
+ case ASUBE:
+ case ASUBECC:
+ case ASUBME:
+ case ASUBMECC:
+ case ASUBZE:
+ case ASUBZECC:
+ case ASLW:
+ case ASLWCC:
+ case ASRW:
+ case ASRWCC:
+ case ASRAW:
+ case ASRAWCC:
+ case ASLD:
+ case ASLDCC:
+ case ASRD:
+ case ASRDCC:
+ case ASRAD:
+ case ASRADCC:
+ case AOR:
+ case AORCC:
+ case AORN:
+ case AORNCC:
+ case AAND:
+ case AANDCC:
+ case AANDN:
+ case AANDNCC:
+ case AXOR:
+ case AXORCC:
+ case ANEG:
+ case ANEGCC:
+ case AMULHW:
+ case AMULHWU:
+ case AMULLW:
+ case AMULLWCC:
+ case ADIVW:
+ case ADIVWCC:
+ case ADIVWU:
+ case ADIVWUCC:
+ case AREM:
+ case AREMCC:
+ case AREMU:
+ case AREMUCC:
+ case AMULLD:
+ case AMULLDCC:
+ case ADIVD:
+ case ADIVDCC:
+ case ADIVDU:
+ case ADIVDUCC:
+ case AREMD:
+ case AREMDCC:
+ case AREMDU:
+ case AREMDUCC:
+ case ANAND:
+ case ANANDCC:
+ case ANOR:
+ case ANORCC:
+ case ARLWMI:
+ case ARLWMICC:
+ case ARLWNM:
+ case ARLWNMCC:
+ return D_REG;
+
+ case AFADDS:
+ case AFADDSCC:
+ case AFADD:
+ case AFADDCC:
+ case AFSUBS:
+ case AFSUBSCC:
+ case AFSUB:
+ case AFSUBCC:
+ case AFMULS:
+ case AFMULSCC:
+ case AFMUL:
+ case AFMULCC:
+ case AFDIVS:
+ case AFDIVSCC:
+ case AFDIV:
+ case AFDIVCC:
+ case AFNEG:
+ case AFNEGCC:
+ return D_FREG;
+ }
+ return D_NONE;
+}
+
+/*
+ * direct reference,
+ * could be set/use depending on
+ * semantics
+ */
+int
+copyas(Addr *a, Addr *v)
+{
+
+ if(regtyp(v))
+ if(a->type == v->type)
+ if(a->reg == v->reg)
+ return 1;
+ return 0;
+}
+
+/*
+ * either direct or indirect
+ */
+int
+copyau(Addr *a, Addr *v)
+{
+
+ if(copyas(a, v))
+ return 1;
+ if(v->type == D_REG)
+ if(a->type == D_OREG)
+ if(v->reg == a->reg)
+ return 1;
+ return 0;
+}
+
+int
+copyau1(Prog *p, Addr *v)
+{
+
+ if(regtyp(v))
+ if(p->from.type == v->type || p->to.type == v->type)
+ if(p->reg == v->reg) {
+ if(a2type(p) != v->type)
+ print("botch a2type %P\n", p);
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * substitute s for v in a
+ * return failure to substitute
+ */
+int
+copysub(Addr *a, Addr *v, Addr *s, int f)
+{
+
+ if(f)
+ if(copyau(a, v))
+ a->reg = s->reg;
+ return 0;
+}
+
+int
+copysub1(Prog *p1, Addr *v, Addr *s, int f)
+{
+
+ if(f)
+ if(copyau1(p1, v))
+ p1->reg = s->reg;
+ return 0;
+}