initial cut at arm optimizer

R=rsc
CC=golang-dev
https://golang.org/cl/3921041

diff --git a/src/cmd/5g/Makefile b/src/cmd/5g/Makefile
index 1da0ef6290c030a6bb05cdbf4af7b42d51b4f524..6873fbc680d70155f36615793d1eeec8d4f1effa 100644 (file)
--- a/src/cmd/5g/Makefile
+++ b/src/cmd/5g/Makefile
@@ -24,6 +24,7 @@ OFILES=\
        cgen64.$O\
        cplx.$O\
        reg.$O\
+       peep.$O\
 
 LIB=\
        ../gc/gc.a\

diff --git a/src/cmd/5g/list.c b/src/cmd/5g/list.c
index 8547bb2f8c2ca521d066fc20d95a546608f99730..ce74d6478dde89ea13ddc7d2bb5522e4ceb90c7e 100644 (file)
--- a/src/cmd/5g/list.c
+++ b/src/cmd/5g/list.c
@@ -154,10 +154,16 @@ Dconv(Fmt *fp)
                break;
 
        case D_BRANCH:
-               if(a->sym != S)
-                       sprint(str, "%s+%d(APC)", a->sym->name, a->offset);
-               else
-                       sprint(str, "%d(APC)", a->offset);
+               if(a->branch == P || a->branch->loc == 0) {
+                       if(a->sym != S)
+                               sprint(str, "%s+%d(APC)", a->sym->name, a->offset);
+                       else
+                               sprint(str, "%d(APC)", a->offset);
+               } else
+                       if(a->sym != S)
+                               sprint(str, "%s+%d(APC)", a->sym->name, a->branch->loc);
+                       else
+                               sprint(str, "%d(APC)", a->branch->loc);
                break;
 
        case D_FCONST:

diff --git a/src/cmd/5g/reg.c b/src/cmd/5g/reg.c
index 4c5b3e31a9b78e1be00425156828fee661810341..46471a016ca7c8dab0e73aa44b7706407a58ce51 100644 (file)
--- a/src/cmd/5g/reg.c
+++ b/src/cmd/5g/reg.c
@@ -34,9 +34,9 @@
 
 #define        P2R(p)  (Reg*)(p->reg)
 
-void   addsplits(void);
-int    onlyone;
-static int     first   = 1;
+       void    addsplits(void);
+       int     noreturn(Prog *p);
+static int     first   = 0;
 
 Reg*
 rega(void)
@@ -137,13 +137,24 @@ regopt(Prog *firstp)
        uint32 vreg;
        Bits bit;
 
-return;
-
-       if(first) {
+       if(first == 0) {
                fmtinstall('Q', Qconv);
 //             exregoffset = D_R13;    // R14,R15 are external
-               first = 0;
        }
+       first++;
+
+//if(!debug['K'])
+//     return;
+
+//if(first != 19) {
+//     return;
+//}
+
+//print("optimizing %S\n", curfn->nname->sym);
+
+//debug['R'] = 2;
+//debug['P'] = 2;
+
 
        // count instructions
        nr = 0;
@@ -152,7 +163,7 @@ return;
 
        // if too big dont bother
        if(nr >= 10000) {
-               print("********** %S is too big (%d)\n", curfn->nname->sym, nr);
+//             print("********** %S is too big (%d)\n", curfn->nname->sym, nr);
                return;
        }
 
@@ -178,7 +189,7 @@ return;
         * allocate pcs
         * find use and set of variables
         */
-print("pass 1\n");
+if(0) print("pass 1\n");
        nr = 0;
        for(p=firstp; p != P; p = p->link) {
                switch(p->as) {
@@ -265,20 +276,15 @@ print("pass 1\n");
                        }
                }
        }
-       if(firstr == R) {
+       if(firstr == R)
                return;
-       }
-
-onlyone++;
-if(onlyone != 1)
-       return;
 
        /*
         * pass 2
         * turn branch references to pointers
         * build back pointers
         */
-print("pass 2\n");
+if(0) print("pass 2\n");
        for(r=firstr; r!=R; r=r->link) {
                p = r->prog;
                if(p->to.type == D_BRANCH) {
@@ -305,7 +311,7 @@ print("pass 2\n");
         * pass 2.5
         * find looping structure
         */
-print("pass 2.5\n");
+if(0) print("pass 2.5\n");
        for(r = firstr; r != R; r = r->link)
                r->active = 0;
        change = 0;
@@ -317,7 +323,7 @@ print("pass 2.5\n");
         *      back until flow graph is complete
         */
 loop1:
-print("loop 1\n");
+if(0) print("loop 1\n");
        change = 0;
        for(r = firstr; r != R; r = r->link)
                r->active = 0;
@@ -325,7 +331,7 @@ print("loop 1\n");
                if(r->prog->as == ARET)
                        prop(r, zbits, zbits);
 loop11:
-print("loop 11\n");
+if(0) print("loop 11\n");
        /* pick up unreachable code */
        i = 0;
        for(r = firstr; r != R; r = r1) {
@@ -347,7 +353,7 @@ print("loop 11\n");
         *      forward until graph is complete
         */
 loop2:
-print("loop 2\n");
+if(0) print("loop 2\n");
        change = 0;
        for(r = firstr; r != R; r = r->link)
                r->active = 0;
@@ -357,7 +363,7 @@ print("loop 2\n");
 
        addsplits();
 
-       if(debug['R'] && debug['v']) {
+       if(debug['R'] > 1) {
                print("\nprop structure:\n");
                for(r = firstr; r != R; r = r->link) {
                        print("%d:%P", r->loop, r->prog);
@@ -394,7 +400,7 @@ print("loop 2\n");
         * isolate regions
         * calculate costs (paint1)
         */
-print("pass 5\n");
+if(0) print("pass 5\n");
        r = firstr;
        if(r) {
                for(z=0; z<BITS; z++)
@@ -429,7 +435,7 @@ print("pass 5\n");
                        rgp->enter = r;
                        rgp->varno = i;
                        change = 0;
-                       if(debug['R'] && debug['v'])
+                       if(debug['R'] > 1)
                                print("\n");
                        paint1(r, i);
                        bit.b[i/32] &= ~(1L<<(i%32));
@@ -442,7 +448,7 @@ print("pass 5\n");
                        rgp->cost = change;
                        nregion++;
                        if(nregion >= NRGN) {
-                               if(debug['R'] && debug['v'])
+                               if(debug['R'] > 1)
                                        print("too many regions\n");
                                goto brk;
                        }
@@ -457,7 +463,6 @@ brk:
         * determine used registers (paint2)
         * replace code (paint3)
         */
-print("pass 6 -- %d regions\n", nregion);
        rgp = region;
        for(i=0; i<nregion; i++) {
                bit = blsh(rgp->varno);
@@ -485,9 +490,9 @@ print("pass 6 -- %d regions\n", nregion);
         * pass 7
         * peep-hole on basic block
         */
-print("pass 7\n");
+if(0) print("pass 7\n");
        if(!debug['R'] || debug['P']) {
-//             peep();
+               peep();
        }
 
        /*
@@ -495,9 +500,12 @@ print("pass 7\n");
         * eliminate nops
         * free aux structures
         */
-       for(p = firstr->prog; p != P; p = p->link){
-               while(p->link && p->link->as == ANOP)
+       for(p = firstp; p != P; p = p->link) {
+               while(p->link != P && p->link->as == ANOP)
                        p->link = p->link->link;
+               if(p->to.type == D_BRANCH)
+                       while(p->to.branch != P && p->to.branch->as == ANOP)
+                               p->to.branch = p->to.branch->link;
        }
        if(r1 != R) {
                r1->link = freer;
@@ -562,15 +570,31 @@ addmove(Reg *r, int bn, int rn, int f)
        if(a->etype == TARRAY || a->sym == S)
                a->type = D_CONST;
 
-       p1->as = AMOVW;
-       if(v->etype == TINT8 || v->etype == TUINT8)
+       switch(v->etype) {
+       default:
+               print("What is this %E\n", v->etype);
+
+       case TINT32:
+       case TUINT32:
+       case TPTR32:
+       case TBOOL:
+               p1->as = AMOVW;
+               break;
+       case TINT8:
+       case TUINT8:
                p1->as = AMOVB;
-       if(v->etype == TINT16 || v->etype == TUINT16)
+               break;
+       case TINT16:
+       case TUINT16:
                p1->as = AMOVH;
-       if(v->etype == TFLOAT)
+               break;
+       case TFLOAT32:
                p1->as = AMOVF;
-       if(v->etype == TFLOAT64)
+               break;
+       case TFLOAT64:
                p1->as = AMOVD;
+               break;
+       }
 
        p1->from.type = D_REG;
        p1->from.reg = rn;
@@ -619,32 +643,72 @@ mkvar(Reg *r, Adr *a, int docon)
        Bits bit;
        Sym *s;
 
+       // mark registers used
        t = a->type;
-       if(t == D_REG && a->reg != NREG)
-               r->regu |= RtoB(a->reg);
-       if(t == D_FREG && a->reg != NREG)
-               r->regu |= FtoB(a->reg);
-       s = a->sym;
-       o = a->offset;
-       et = a->etype;
-       if(s == S) {
-               if(t != D_CONST || !docon || a->reg != NREG)
-                       goto none;
-               et = TINT32;
+       n = D_NONE;
+
+       switch(t) {
+       default:
+               print("type %d %d %D\n", t, a->name, a);
+               goto none;
+
+       case D_NONE:
+       case D_CONST:
+       case D_FCONST:
+       case D_BRANCH:
+               goto none;
+
+       case D_REGREG:
+               if(a->offset != NREG)
+                       r->regu |= RtoB(a->offset);
+               // fallthrough
+
+       case D_REG:
+       case D_SHIFT:
+       case D_OREG:
+               if(a->reg != NREG)
+                       r->regu |= RtoB(a->reg);
+               break;
+
+       case D_FREG:
+               if(a->reg != NREG)
+                       r->regu |= FtoB(a->reg);
+               break;
        }
-       if(t == D_CONST) {
-//             if(s == S && sval(o))
-//                     goto none;
+
+       switch(a->name) {
+       default:
+               goto none;
+
+       case D_EXTERN:
+       case D_STATIC:
+       case D_AUTO:
+       case D_PARAM:
+               n = a->name;
+               break;
        }
 
        flag = 0;
+//     if(a->pun)
+//             flag = 1;
+
+       s = a->sym;
+       if(s == S)
+               goto none;
+       if(s->name[0] == '.')
+               goto none;
+       et = a->etype;
+       o = a->offset;
+       w = a->width;
+
        for(i=0; i<nvar; i++) {
                v = var+i;
                if(v->sym == s && v->name == n) {
                        if(v->offset == o)
                        if(v->etype == et)
                        if(v->width == w)
-                               return blsh(i);
+                               if(!flag)
+                                       return blsh(i);
 
                        // if they overlaps, disable both
                        if(overlap(v->offset, v->width, o, w)) {
@@ -654,12 +718,11 @@ mkvar(Reg *r, Adr *a, int docon)
                }
        }
 
-//     if(a->pun)
-//             flag = 1;
-
        switch(et) {
        case 0:
        case TFUNC:
+       case TARRAY:
+       case TSTRING:
                goto none;
        }
 
@@ -681,7 +744,7 @@ mkvar(Reg *r, Adr *a, int docon)
        v->addr = flag;         // funny punning
 
        if(debug['R'])
-               print("bit=%2d et=%2d %D\n", i, et, a);
+               print("bit=%2d et=%E pun=%d %D\n", i, et, flag, a);
 
 out:
        bit = blsh(i);
@@ -692,9 +755,6 @@ out:
                for(z=0; z<BITS; z++)
                        params.b[z] |= bit.b[z];
 
-//     if(v->etype != et || !typechlpfd[et])   /* funny punning */
-//             for(z=0; z<BITS; z++)
-//                     addrs.b[z] |= bit.b[z];
 //     if(t == D_CONST) {
 //             if(s == S) {
 //                     for(z=0; z<BITS; z++)
@@ -738,6 +798,8 @@ prop(Reg *r, Bits ref, Bits cal)
                }
                switch(r1->prog->as) {
                case ABL:
+                       if(noreturn(r1->prog))
+                               break;
                        for(z=0; z<BITS; z++) {
                                cal.b[z] |= ref.b[z] | externs.b[z];
                                ref.b[z] = 0;
@@ -753,9 +815,10 @@ prop(Reg *r, Bits ref, Bits cal)
 
                case ARET:
                        for(z=0; z<BITS; z++) {
-                               cal.b[z] = externs.b[z];
+                               cal.b[z] = externs.b[z] | ovar.b[z];
                                ref.b[z] = 0;
                        }
+                       break;
                }
                for(z=0; z<BITS; z++) {
                        ref.b[z] = (ref.b[z] & ~r1->set.b[z]) |
@@ -1008,7 +1071,7 @@ paint1(Reg *r, int bn)
 
        if(LOAD(r) & ~(r->set.b[z] & ~(r->use1.b[z]|r->use2.b[z])) & bb) {
                change -= CLOAD * r->loop;
-               if(debug['R'] && debug['v'])
+               if(debug['R'] > 1)
                        print("%d%P\td %Q $%d\n", r->loop,
                                r->prog, blsh(bn), change);
        }
@@ -1018,21 +1081,21 @@ paint1(Reg *r, int bn)
 
                if(r->use1.b[z] & bb) {
                        change += CREF * r->loop;
-                       if(debug['R'] && debug['v'])
+                       if(debug['R'] > 1)
                                print("%d%P\tu1 %Q $%d\n", r->loop,
                                        p, blsh(bn), change);
                }
 
                if((r->use2.b[z]|r->set.b[z]) & bb) {
                        change += CREF * r->loop;
-                       if(debug['R'] && debug['v'])
+                       if(debug['R'] > 1)
                                print("%d%P\tu2 %Q $%d\n", r->loop,
                                        p, blsh(bn), change);
                }
 
                if(STORE(r) & r->regdiff.b[z] & bb) {
                        change -= CLOAD * r->loop;
-                       if(debug['R'] && debug['v'])
+                       if(debug['R'] > 1)
                                print("%d%P\tst %Q $%d\n", r->loop,
                                        p, blsh(bn), change);
                }
@@ -1244,3 +1307,27 @@ BtoF(int32 b)
                return 0;
        return bitno(b) - 16;
 }
+
+static Sym*    symlist[10];
+
+int
+noreturn(Prog *p)
+{
+       Sym *s;
+       int i;
+
+       if(symlist[0] == S) {
+               symlist[0] = pkglookup("panicindex", runtimepkg);
+               symlist[1] = pkglookup("panicslice", runtimepkg);
+               symlist[2] = pkglookup("throwinit", runtimepkg);
+               symlist[3] = pkglookup("panic", runtimepkg);
+       }
+
+       s = p->to.sym;
+       if(s == S)
+               return 0;
+       for(i=0; symlist[i]!=S; i++)
+               if(s == symlist[i])
+                       return 1;
+       return 0;
+}