[PATCH] D108731: [TwoAddressInstructionPass] Improve the SrcRegMap and DstRegMap computation

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


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Comment at: llvm/lib/CodeGen/TwoAddressInstructionPass.cpp:400
+  if (UseMI.isCommutable()) {
+    unsigned Src1 = TII->CommuteAnyOperandIndex;
+    unsigned Src2 = UseMI.findRegisterUseOperandIdx(Reg);
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Use `TargetInstrInfo::CommuteAnyOperandIndex` so this doesn't look like a member access?


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Comment at: llvm/lib/CodeGen/TwoAddressInstructionPass.cpp:436
+  Register Reg;
+  if (MO.isReg())
+    Reg = MO.getReg();
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Why not check isReg() inside the loop and call getReg() in the loop. That wouldn't be that expensive would it?


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Comment at: llvm/lib/CodeGen/TwoAddressInstructionPass.cpp:661
-    if (!isNew)
-      assert(SrcRegMap[NewReg] == Reg && "Can't map to two src registers!");
     VirtRegPairs.push_back(NewReg);
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Is this assert no longer valid?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D108731/new/

https://reviews.llvm.org/D108731