[PATCH] D31852: [PowerPC] Convert reg/reg instructions fed by constants to reg/imm instructions (pre and post RA)

[Nemanja Ivanovic via Phabricator via llvm-commits]

nemanjai added inline comments.


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Comment at: lib/Target/PowerPC/PPCInstrInfo.cpp:2314
+  unsigned ConstantOperand = ~0U;
+  MachineInstr *DefMI = getConstantDefMI(MI, ConstantOperand,
+                                         SeenIntermediateUse);
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hfinkel wrote:
> I see why you did this, but I don't like the interface to this function: it is unintuitive that it might return non-null, and yet, you also need to check that the ConstantOp is not -1 to know if the return value is valid. Can you please change this so that it uniformly returns non-null only if it succeeds (and, thus, the constant is valid).
That is a really good point. I'll change it to return non-null only if the constant operand is a valid operand of the instruction.


Repository:
  rL LLVM

https://reviews.llvm.org/D31852