diff options
| -rw-r--r-- | all.h | 2 | ||||
| -rw-r--r-- | cfg.c | 48 | ||||
| -rw-r--r-- | fold.c | 12 |
3 files changed, 34 insertions, 28 deletions
diff --git a/all.h b/all.h index cc94161..a40627c 100644 --- a/all.h +++ b/all.h @@ -547,7 +547,7 @@ void err(char *, ...) __attribute__((noreturn)); /* cfg.c */ Blk *blknew(void); -void blkdel(Blk *); +void edgedel(Blk *, Blk **); void fillpreds(Fn *); void fillrpo(Fn *); void filldom(Fn *); diff --git a/cfg.c b/cfg.c index 5385811..8c6278f 100644 --- a/cfg.c +++ b/cfg.c @@ -12,32 +12,33 @@ blknew() } void -blkdel(Blk *b) +edgedel(Blk *bs, Blk **pbd) { - Blk *s, **ps, *succ[3]; + Blk *bd; Phi *p; uint a; + int mult; - succ[0] = b->s1; - succ[1] = b->s2 == b->s1 ? 0 : b->s2; - succ[2] = 0; - for (ps=succ; (s=*ps); ps++) { - for (p=s->phi; p; p=p->link) { - for (a=0; p->blk[a]!=b; a++) - assert(a+1<p->narg); - p->narg--; - memmove(&p->blk[a], &p->blk[a+1], - sizeof p->blk[0] * (p->narg-a)); - memmove(&p->arg[a], &p->arg[a+1], - sizeof p->arg[0] * (p->narg-a)); - } - if (s->npred != 0) { - for (a=0; s->pred[a]!=b; a++) - assert(a+1<s->npred); - s->npred--; - memmove(&s->pred[a], &s->pred[a+1], - sizeof s->pred[0] * (s->npred-a)); - } + bd = *pbd; + mult = 1 + (bs->s1 == bs->s2); + *pbd = 0; + if (!bd || mult > 1) + return; + for (p=bd->phi; p; p=p->link) { + for (a=0; p->blk[a]!=bs; a++) + assert(a+1<p->narg); + p->narg--; + memmove(&p->blk[a], &p->blk[a+1], + sizeof p->blk[0] * (p->narg-a)); + memmove(&p->arg[a], &p->arg[a+1], + sizeof p->arg[0] * (p->narg-a)); + } + if (bd->npred != 0) { + for (a=0; bd->pred[a]!=bs; a++) + assert(a+1<bd->npred); + bd->npred--; + memmove(&bd->pred[a], &bd->pred[a+1], + sizeof bd->pred[0] * (bd->npred-a)); } } @@ -110,7 +111,8 @@ fillrpo(Fn *f) f->rpo = alloc(f->nblk * sizeof f->rpo[0]); for (p=&f->start; (b=*p);) { if (b->id == -1u) { - blkdel(b); + edgedel(b, &b->s1); + edgedel(b, &b->s2); *p = b->link; } else { b->id -= n; diff --git a/fold.c b/fold.c index c8d490c..0cbd6fa 100644 --- a/fold.c +++ b/fold.c @@ -275,7 +275,8 @@ fold(Fn *fn) d = 1; if (debug['F']) fprintf(stderr, "%s ", b->name); - blkdel(b); + edgedel(b, &b->s1); + edgedel(b, &b->s2); *pb = b->link; continue; } @@ -296,11 +297,14 @@ fold(Fn *fn) renref(&i->arg[n]); renref(&b->jmp.arg); if (b->jmp.type == Jjnz && rtype(b->jmp.arg) == RCon) { - b->jmp.type = Jjmp; - if (czero(&fn->con[b->jmp.arg.val], 0)) + if (czero(&fn->con[b->jmp.arg.val], 0)) { + edgedel(b, &b->s1); b->s1 = b->s2; + b->s2 = 0; + } else + edgedel(b, &b->s2); + b->jmp.type = Jjmp; b->jmp.arg = R; - b->s2 = 0; } pb = &b->link; } |