[PATCH] D132443: [LSR] Fold terminal condition to other IV when possible

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


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Comment at: llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp:6634
+  auto IsToFold = [&](PHINode &PN) -> bool {
+    if (PN.getNumIncomingValues() != 2)
+      return false;
----------------
Is `PN.getNumIncomingValues() == 2` implied by LoopSimplifyForm?


================
Comment at: llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp:6661
+  auto IsToHelpFold = [&](PHINode &PN) -> bool {
+    if (PN.getNumIncomingValues() != 2)
+      return false;
----------------
Is `PN.getNumIncomingValues() == 2` implied by LoopSimplifyForm?


================
Comment at: llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp:6668
+    // and down in the actual transformation.
+    return PN.getBasicBlockIndex(LoopPreheader) != -1 &&
+           PN.getBasicBlockIndex(LoopLatch) != -1 &&
----------------
Are the LoopPreheader and LoopLatch being predecessors of the phi implied by LoopSimplify form?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D132443/new/

https://reviews.llvm.org/D132443