[PATCH] D22466: Avoid false dependencies of undef machine operands

[Michael Kuperstein via llvm-commits]

mkuper added inline comments.

================
Comment at: lib/CodeGen/ExecutionDepsFix.cpp:492
@@ +491,3 @@
+
+  const TargetRegisterClass* OpRC = MI->getRegClassConstraint(OpIdx, TII, TRI);
+
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myatsina wrote:
> This is a bug fixed exposed by Craig Topper's commit #276393. 
> Now using the register class of the actual machine instruction operand I want to replace.
This looks a bit weird.
It would probably be better to use MRI->getRegClass(OriginalReg). 
(We already query MachineRegisterInfo in runOnFunction, you can convert that to a member)


Repository:
  rL LLVM

https://reviews.llvm.org/D22466