Change PHINode::hasConstantValue to have a DominatorTree argument

instead of a bool argument, and to do the dominator check itself.
This makes it eaiser to use when DominatorTree information is
available.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80920 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman
2009-09-03 15:34:35 +00:00
parent dd12de686c
commit bccfc24c4e
7 changed files with 49 additions and 37 deletions

View File

@@ -255,7 +255,7 @@ ReprocessLoop:
PHINode *PN;
for (BasicBlock::iterator I = L->getHeader()->begin();
(PN = dyn_cast<PHINode>(I++)); )
if (Value *V = PN->hasConstantValue()) {
if (Value *V = PN->hasConstantValue(DT)) {
if (AA) AA->deleteValue(PN);
PN->replaceAllUsesWith(V);
PN->eraseFromParent();
@@ -417,14 +417,13 @@ static PHINode *FindPHIToPartitionLoops(Loop *L, DominatorTree *DT,
for (BasicBlock::iterator I = L->getHeader()->begin(); isa<PHINode>(I); ) {
PHINode *PN = cast<PHINode>(I);
++I;
if (Value *V = PN->hasConstantValue())
if (!isa<Instruction>(V) || DT->dominates(cast<Instruction>(V), PN)) {
// This is a degenerate PHI already, don't modify it!
PN->replaceAllUsesWith(V);
if (AA) AA->deleteValue(PN);
PN->eraseFromParent();
continue;
}
if (Value *V = PN->hasConstantValue(DT)) {
// This is a degenerate PHI already, don't modify it!
PN->replaceAllUsesWith(V);
if (AA) AA->deleteValue(PN);
PN->eraseFromParent();
continue;
}
// Scan this PHI node looking for a use of the PHI node by itself.
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)