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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85635 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman 2009-10-30 23:15:43 +00:00
parent 1107c63efe
commit 0e747beb3c
1 changed files with 5 additions and 0 deletions
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lib/Transforms/Utils/SimplifyCFG.cpp
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@ -1753,8 +1753,13 @@ static bool SimplifyCondBranchToCondBranch(BranchInst *PBI, BranchInst *BI) {
/// nodes in this block. This doesn't try to be clever about PHI nodes
/// which differ only in the order of the incoming values, but instcombine
/// orders them so it usually won't matter.
///
static bool EliminateDuplicatePHINodes(BasicBlock *BB) {
bool Changed = false;
// This implementation doesn't currently consider undef operands
// specially. Theroetically, two phis which are identical except for
// one having an undef where the other doesn't could be collapsed.
// Map from PHI hash values to PHI nodes. If multiple PHIs have
// the same hash value, the element is the first PHI in the