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| author | Nick Lewycky <nicholas@mxc.ca> | 2009-09-19 19:00:06 +0000 |
|---|---|---|
| committer | Nick Lewycky <nicholas@mxc.ca> | 2009-09-19 19:00:06 +0000 |
| commit | 3b8bd05081c9969cca43033782a1f984a12ae41d (patch) | |
| tree | 285371efdef83e57f8bf93e89ff2557b22761021 /llvm/lib/Analysis/SparsePropagation.cpp | |
| parent | aecd74d8951e62fd60e60cbb112e1e78dee210f5 (diff) | |
| download | bcm5719-llvm-3b8bd05081c9969cca43033782a1f984a12ae41d.tar.gz bcm5719-llvm-3b8bd05081c9969cca43033782a1f984a12ae41d.zip | |
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llvm-svn: 82319
Diffstat (limited to 'llvm/lib/Analysis/SparsePropagation.cpp')
| -rw-r--r-- | llvm/lib/Analysis/SparsePropagation.cpp | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/llvm/lib/Analysis/SparsePropagation.cpp b/llvm/lib/Analysis/SparsePropagation.cpp index 8a74745dd3f..b7844f02276 100644 --- a/llvm/lib/Analysis/SparsePropagation.cpp +++ b/llvm/lib/Analysis/SparsePropagation.cpp @@ -223,6 +223,9 @@ void SparseSolver::visitTerminatorInst(TerminatorInst &TI) { } void SparseSolver::visitPHINode(PHINode &PN) { + // The lattice function may store more information on a PHINode than could be + // computed from its incoming values. For example, SSI form stores its sigma + // functions as PHINodes with a single incoming value. if (LatticeFunc->IsSpecialCasedPHI(&PN)) { LatticeVal IV = LatticeFunc->ComputeInstructionState(PN, *this); if (IV != LatticeFunc->getUntrackedVal()) |
