diff options
Diffstat (limited to 'copy.c')
| -rw-r--r-- | copy.c | 48 |
1 files changed, 43 insertions, 5 deletions
diff --git a/copy.c b/copy.c index bcb7b4d..7442306 100644 --- a/copy.c +++ b/copy.c @@ -51,13 +51,51 @@ visitphi(Phi *p, Ref *cp, RList ***pw) update(p->to, r, cp, pw); } +static int +iscopy(Ins *i, Ref r, Fn *fn) +{ + static bits extcpy[] = { + [WFull] = 0, + [Wsb] = BIT(Wsb) | BIT(Wsh) | BIT(Wsw), + [Wub] = BIT(Wub) | BIT(Wuh) | BIT(Wuw), + [Wsh] = BIT(Wsh) | BIT(Wsw), + [Wuh] = BIT(Wuh) | BIT(Wuw), + [Wsw] = BIT(Wsw), + [Wuw] = BIT(Wuw), + }; + int k, w; + Tmp *t; + + if (i->op == Ocopy) + return 1; + if (!isext(i->op)) + return 0; + if (i->op == Oextsw || i->op == Oextuw) + if (i->cls == Kw) + return 1; + if (rtype(r) == RTmp) { + t = &fn->tmp[r.val]; + w = t->width; + k = t->cls; + assert(k == Kw || k == Kl); + } else { + assert(rtype(r) == RCon); + w = WFull; + k = Kl; + } + if (i->cls == Kl && k == Kw) + /* not enough bits in r */ + return 0; + return (BIT(Wsb + (i->op - Oextsb)) & extcpy[w]) != 0; +} + static void -visitins(Ins *i, Ref *cp, RList ***pw) +visitins(Ins *i, Ref *cp, RList ***pw, Fn *fn) { Ref r; - if (i->op == Ocopy) { - r = copyof(i->arg[0], cp); + r = copyof(i->arg[0], cp); + if (iscopy(i, r, fn)) { update(i->to, r, cp, pw); } else if (!req(i->to, R)) { assert(rtype(i->to) == RTmp); @@ -91,7 +129,7 @@ copy(Fn *fn) for (p=b->phi; p; p=p->link) visitphi(p, cp, &pw); for (i=b->ins; i-b->ins < b->nins; i++) - visitins(i, cp, &pw); + visitins(i, cp, &pw, fn); } while ((w1=w)) { t = w->t; @@ -103,7 +141,7 @@ copy(Fn *fn) visitphi(u->u.phi, cp, &pw); break; case UIns: - visitins(u->u.ins, cp, &pw); + visitins(u->u.ins, cp, &pw, fn); break; case UJmp: break; |