[PATCH] D136201: [InstCombine] Handle PHI nodes when eliminating constant memcpy

[Nikita Popov via Phabricator via llvm-commits]

nikic added inline comments.


================
Comment at: llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp:52
   while (!ValuesToInspect.empty()) {
-    auto ValuePair = ValuesToInspect.pop_back_val();
-    const bool IsOffset = ValuePair.second;
-    for (auto &U : ValuePair.first->uses()) {
-      auto *I = cast<Instruction>(U.getUser());
+    auto [Val, IsOffset, LastPHI] = ValuesToInspect.pop_back_val();
+
----------------
Why do we need the LastPHI variable? I'd have expected that just setting `IsOffset=true` is equivalent? (With a rename `IsOffset` -> `ForbidCopy` or something?)


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D136201/new/

https://reviews.llvm.org/D136201