[PATCH] D129661: [AMDGPU] Update LiveVariables after killing an immediate def

[Jay Foad via Phabricator via llvm-commits]

foad created this revision.
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D114999 <https://reviews.llvm.org/D114999> added code to kill an immediate def if it was folded into its
only use by convertToThreeAddress. This patch updates LiveVariables when
that happens in order to fix verification failures exposed by D129213 <https://reviews.llvm.org/D129213>.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D129661

Files:
  llvm/lib/Target/AMDGPU/SIInstrInfo.cpp


Index: llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
===================================================================
--- llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
+++ llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
@@ -3335,15 +3335,18 @@
       (ST.getConstantBusLimit(Opc) > 1 || !Src0->isReg() ||
        !RI.isSGPRReg(MBB.getParent()->getRegInfo(), Src0->getReg()))) {
     MachineInstr *DefMI;
-    const auto killDef = [&DefMI, &MBB, this]() -> void {
+    const auto killDef = [&]() -> void {
       const MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
       // The only user is the instruction which will be killed.
-      if (!MRI.hasOneNonDBGUse(DefMI->getOperand(0).getReg()))
+      Register DefReg = DefMI->getOperand(0).getReg();
+      if (!MRI.hasOneNonDBGUse(DefReg))
         return;
       // We cannot just remove the DefMI here, calling pass will crash.
       DefMI->setDesc(get(AMDGPU::IMPLICIT_DEF));
       for (unsigned I = DefMI->getNumOperands() - 1; I != 0; --I)
         DefMI->removeOperand(I);
+      if (LV)
+        LV->getVarInfo(DefReg).AliveBlocks.clear();
     };
 
     int64_t Imm;


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