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Don't confuse canonicalize and lookup. Fixes predsimplify.reg4.ll. Also 

corrects missing optimization opportunity removing cases from a switch.

llvm-svn: 30009
This commit is contained in:
Nick Lewycky 2006-09-01 03:26:35 +00:00
parent 31305c45da
commit f6f529d008
1 changed files with 18 additions and 19 deletions
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37
llvm/lib/Transforms/Scalar/PredicateSimplifier.cpp
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@ -576,30 +576,29 @@ void PredicateSimplifier::visit(BranchInst *BI,
void PredicateSimplifier::visit(SwitchInst *SI,
DominatorTree::Node *DTNode, PropertySet KP) {
Value *Condition = SI->getCondition();
DEBUG(assert(Condition == KP.canonicalize(Condition) &&
"Instruction wasn't already canonicalized?"));
// If there's an NEProperty covering this SwitchInst, we may be able to
// eliminate one of the cases.
if (Value *C = KP.lookup(Condition)) {
Condition = C;
for (PropertySet::ConstPropertyIterator I = KP.Properties.begin(),
E = KP.Properties.end(); I != E; ++I) {
if (I->Opcode != PropertySet::NE) continue;
Value *V1 = KP.lookup(I->V1),
*V2 = KP.lookup(I->V2);
if (V1 != C && V2 != C) continue;
for (PropertySet::ConstPropertyIterator I = KP.Properties.begin(),
E = KP.Properties.end(); I != E; ++I) {
if (I->Opcode != PropertySet::NE) continue;
Value *V1 = KP.canonicalize(I->V1),
*V2 = KP.canonicalize(I->V2);
if (V1 != Condition && V2 != Condition) continue;
// Is one side a number?
ConstantInt *CI = dyn_cast<ConstantInt>(KP.lookup(I->V1));
if (!CI) CI = dyn_cast<ConstantInt>(KP.lookup(I->V2));
// Is one side a number?
ConstantInt *CI = dyn_cast<ConstantInt>(KP.canonicalize(I->V1));
if (!CI) CI = dyn_cast<ConstantInt>(KP.canonicalize(I->V2));
if (CI) {
unsigned i = SI->findCaseValue(CI);
if (i != 0) {
SI->getSuccessor(i)->removePredecessor(SI->getParent());
SI->removeCase(i);
modified = true;
++NumSwitchCases;
}
if (CI) {
unsigned i = SI->findCaseValue(CI);
if (i != 0) {
SI->getSuccessor(i)->removePredecessor(SI->getParent());
SI->removeCase(i);
modified = true;
++NumSwitchCases;
}
}
}