diff options
| -rw-r--r-- | all.h | 1 | ||||
| -rw-r--r-- | main.c | 1 | ||||
| -rw-r--r-- | ssa.c | 84 |
3 files changed, 81 insertions, 5 deletions
diff --git a/all.h b/all.h index 74feafe..7a636cc 100644 --- a/all.h +++ b/all.h @@ -529,6 +529,7 @@ void filluse(Fn *); void fillpreds(Fn *); void fillrpo(Fn *); void ssa(Fn *); +void ssacheck(Fn *); /* copy.c */ void copy(Fn *); diff --git a/main.c b/main.c index 5fad26e..473eaf3 100644 --- a/main.c +++ b/main.c @@ -48,6 +48,7 @@ func(Fn *fn) memopt(fn); ssa(fn); filluse(fn); + ssacheck(fn); copy(fn); filluse(fn); fold(fn); diff --git a/ssa.c b/ssa.c index 4be58ba..04ccc24 100644 --- a/ssa.c +++ b/ssa.c @@ -30,6 +30,7 @@ adduse(Tmp *tmp, int ty, Blk *b, ...) } /* fill usage, phi, and class information + * must not change .visit fields */ void filluse(Fn *fn) @@ -94,8 +95,7 @@ addpred(Blk *bp, Blk *bc) bc->pred[bc->visit++] = bp; } -/* fill predecessors information in blocks - */ +/* fill predecessors information in blocks */ void fillpreds(Fn *f) { @@ -140,8 +140,7 @@ rporec(Blk *b, int x) return x - 1; } -/* fill the rpo information in blocks - */ +/* fill the rpo information */ void fillrpo(Fn *f) { @@ -469,7 +468,7 @@ renblk(Blk *b, Name **stk, Fn *fn) renblk(s, stk, fn); } -/* require ndef */ +/* require rpo and ndef */ void ssa(Fn *fn) { @@ -509,3 +508,78 @@ ssa(Fn *fn) printfn(fn, stderr); } } + +static int +phicheck(Phi *p, Blk *b, Ref t) +{ + Blk *b1; + uint n; + + for (n=0; n<p->narg; n++) + if (req(p->arg[n], t)) { + b1 = p->blk[n]; + if (b1 != b && !sdom(b, b1)) + return 1; + } + return 0; +} + +/* require use and ssa */ +void +ssacheck(Fn *fn) +{ + Tmp *t; + Ins *i; + Phi *p; + Use *u; + Blk *b, *bu; + Ref r; + + for (t=&fn->tmp[Tmp0]; t-fn->tmp < fn->ntmp; t++) + if (t->ndef > 1) + err("ssa temporary %%%s defined more than once", + t->name); + for (b=fn->start; b; b=b->link) { + for (p=b->phi; p; p=p->link) { + r = p->to; + t = &fn->tmp[r.val]; + for (u=t->use; u-t->use < t->nuse; u++) { + bu = fn->rpo[u->bid]; + if (u->type == UPhi) { + if (phicheck(u->u.phi, b, r)) + goto Err; + } else + if (bu != b && !sdom(b, bu)) + goto Err; + } + } + for (i=b->ins; i-b->ins < b->nins; i++) { + if (rtype(i->to) != RTmp) + continue; + r = i->to; + t = &fn->tmp[r.val]; + for (u=t->use; u-t->use < t->nuse; u++) { + bu = fn->rpo[u->bid]; + if (u->type == UPhi) { + if (phicheck(u->u.phi, b, r)) + goto Err; + } else { + if (bu == b) { + if (u->type == UIns) + if (u->u.ins <= i) + goto Err; + } else + if (!sdom(b, bu)) + goto Err; + } + } + } + } + return; +Err: + if (t->visit) + die("%%%s violates ssa invariant", t->name); + else + err("ssa temporary %%%s is used undefined in @%s", + t->name, bu->name); +} |