[PATCH] D134641: [AMDGPU][Backend] Fix user-after-free in AMDGPUReleaseVGPRs::isLastVGPRUseVMEMStore

[Matt Arsenault via Phabricator via llvm-commits]

arsenm added inline comments.


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Comment at: llvm/lib/Target/AMDGPU/AMDGPUReleaseVGPRs.cpp:70
+      BlockVMEMStore.resize(MF.getNumBlockIDs());
+      for (auto &MBB : MF) {
+        BlockVMEMStore[MBB.getNumber()] = lastBlockVGPRUseIsVMEMStore(MBB);
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I'd expect this to be the post_order loop


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Comment at: llvm/lib/Target/AMDGPU/AMDGPUReleaseVGPRs.cpp:76
+      for (auto *MBB : reverse(PostOrder)) {
+        auto LastUseIsVMEMStore = BlockVMEMStore[MBB->getNumber()];
+        LastUseIsVMEMStore = LastUseIsVMEMStore ||
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Just use bool?


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Comment at: llvm/lib/Target/AMDGPU/AMDGPUReleaseVGPRs.cpp:77
+        auto LastUseIsVMEMStore = BlockVMEMStore[MBB->getNumber()];
+        LastUseIsVMEMStore = LastUseIsVMEMStore ||
+                             any_of(MBB->predecessors(),
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This looks like a dead variable?


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D134641/new/

https://reviews.llvm.org/D134641