diff options
| -rw-r--r-- | mem.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/mem.c b/mem.c index a574e1f..7570f19 100644 --- a/mem.c +++ b/mem.c @@ -197,7 +197,7 @@ coalesce(Fn *fn) Blk *b, **ps, *succ[3]; Ins *i; Use *u; - Tmp *t; + Tmp *t, *ts; Ref *arg; bits x; int n, m, nsl, ip, *stk; @@ -213,6 +213,7 @@ coalesce(Fn *fn) t->visit = -1; if (t->alias.type == ALoc) if (t->alias.slot == &t->alias) + if (t->bid == fn->start->id) if (t->alias.u.loc.sz != -1) { t->visit = nsl; vgrow(&sl, ++nsl); @@ -356,11 +357,22 @@ coalesce(Fn *fn) /* substitute fused slots */ for (s=sl; s<&sl[nsl]; s++) { - if (s->s == s) - continue; t = &fn->tmp[s->t]; assert(t->ndef == 1 && t->def); + if (s->s == s) + continue; *t->def = (Ins){.op = Onop}; + ts = &fn->tmp[s->s->t]; + assert(t->bid == ts->bid); + if (t->def < ts->def) { + /* make sure the slot we + * selected has a def that + * dominates its new uses + */ + *t->def = *ts->def; + *ts->def = (Ins){.op = Onop}; + ts->def = t->def; + } for (u=t->use; u<&t->use[t->nuse]; u++) { if (u->type == UJmp) { b = fn->rpo[u->bid]; |