diff options
Diffstat (limited to 'llvm/lib/Analysis')
| -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()) |
