diff options
Diffstat (limited to 'fold.c')
| -rw-r--r-- | fold.c | 64 |
1 files changed, 34 insertions, 30 deletions
diff --git a/fold.c b/fold.c index ea1cb6e..c507101 100644 --- a/fold.c +++ b/fold.c @@ -73,9 +73,8 @@ visitphi(Phi *p, int n, Fn *fn) dead = edge[m][1].dead; else die("invalid phi argument"); - if (!dead) { - m = latval(p->arg[a]); - assert(m != Top); + m = latval(p->arg[a]); + if (!dead && m != Top) { if (v != Top && (v == Bot || m == Bot || v != m)) v = Bot; else @@ -100,9 +99,10 @@ visitins(Ins *i, Fn *fn) r = latval(i->arg[1]); else r = CON_Z.val; - assert(l != Top && r != Top); if (l == Bot || r == Bot) v = Bot; + else if (l == Top || r == Top) + v = Top; else v = opfold(i->op, i->cls, &fn->con[l], &fn->con[r], fn); } else @@ -157,6 +157,23 @@ initedge(Edge *e, Blk *s) e->work = 0; } +static int +renref(Ref *r, Fn *fn) +{ + if (rtype(*r) == RTmp) + switch (val[r->val]) { + case Top: + err("temporary %%%s is ill-defined", + fn->tmp[r->val].name); + case Bot: + break; + default: + *r = CON(val[r->val]); + return 1; + } + return 0; +} + /* require rpo, use, pred */ void fold(Fn *fn) @@ -166,7 +183,7 @@ fold(Fn *fn) Blk *b, **pb; Phi *p, **pp; Ins *i; - int n, l, d; + int n, d; uint a; val = emalloc(fn->ntmp * sizeof val[0]); @@ -210,15 +227,14 @@ fold(Fn *fn) } else if (nuse) { u = usewrk[--nuse]; - if (u->type == UPhi) { - visitphi(u->u.phi, u->bid, fn); - continue; - } n = u->bid; b = fn->rpo[n]; if (b->visit == 0) continue; switch (u->type) { + case UPhi: + visitphi(u->u.phi, u->bid, fn); + break; case UIns: visitins(u->u.ins, fn); break; @@ -263,34 +279,22 @@ fold(Fn *fn) *pp = p->link; else { for (a=0; a<p->narg; a++) - if (rtype(p->arg[a]) == RTmp) - if ((l=val[p->arg[a].val]) != Bot) - p->arg[a] = CON(l); + renref(&p->arg[a], fn); pp = &p->link; } - for (i=b->ins; i-b->ins < b->nins; i++) { - if (rtype(i->to) == RTmp) - if (val[i->to.val] != Bot) { + for (i=b->ins; i-b->ins < b->nins; i++) + if (renref(&i->to, fn)) *i = (Ins){.op = ONop}; - continue; - } - for (n=0; n<2; n++) - if (rtype(i->arg[n]) == RTmp) - if ((l=val[i->arg[n].val]) != Bot) - i->arg[n] = CON(l); - } - if (b->jmp.type == JJnz) { - if ((l=latval(b->jmp.arg)) != Bot) { + else + for (n=0; n<2; n++) + renref(&i->arg[n], fn); + renref(&b->jmp.arg, fn); + if (b->jmp.type == JJnz && rtype(b->jmp.arg) == RCon) { b->jmp.type = JJmp; b->jmp.arg = R; - if (czero(&fn->con[l], 0)) + if (czero(&fn->con[b->jmp.arg.val], 0)) b->s1 = b->s2; b->s2 = 0; - } - } else { - if (rtype(b->jmp.arg) == RTmp) - if ((l=val[b->jmp.arg.val]) != Bot) - b->jmp.arg = CON(l); } pb = &b->link; } |