[PATCH] D77210: [GlobalISel] Combine sext([sz]ext) -> [sz]ext, zext(zext) -> zext

[Matt Arsenault via Phabricator via llvm-commits]

arsenm added inline comments.


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Comment at: llvm/include/llvm/CodeGen/GlobalISel/LegalizationArtifactCombiner.h:128
+      LLVM_DEBUG(dbgs() << ".. Combine MI: " << MI);
+      Builder.buildZExt(DstReg, ZextSrc);
+      markInstAndDefDead(MI, *MRI.getVRegDef(SrcReg), DeadInsts);
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Can you just replace the source?


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Comment at: llvm/include/llvm/CodeGen/GlobalISel/LegalizationArtifactCombiner.h:180
+    if (mi_match(SrcReg, MRI,
+                 m_all_of(m_MInstr(ExtMI), m_any_of(m_GZExt(m_Reg(ExtSrc)),
+                                                    m_GSExt(m_Reg(ExtSrc)))))) {
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Why the m_all_of?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D77210/new/

https://reviews.llvm.org/D77210