[PATCH] D36990: [GISel]: Translate phi into generic G_PHI instruction

[Aditya Nandakumar via Phabricator via llvm-commits]

aditya_nandakumar added inline comments.


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Comment at: lib/Target/AArch64/AArch64RegisterBankInfo.cpp:423
   // or already have some operands assigned to banks.
-  if (!isPreISelGenericOpcode(Opc)) {
+  if (!isPreISelGenericOpcode(Opc) || Opc == TargetOpcode::G_PHI) {
     const RegisterBankInfo::InstructionMapping &Mapping =
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qcolombet wrote:
> We should need to do that.
> Could you describe what happen if you don't?
When it returns the best mapping, it creates for NumOperands (say with 2 PHI values - it's 5). Then it fails the verification of the best mapping.
assert(NumOperands == (isCopyLike(MI) ? 1 : MI.getNumOperands()) && "NumOperands must match, see constructor");
I made the change so G_PHI would have been treated as it were a PHI.


Repository:
  rL LLVM

https://reviews.llvm.org/D36990