[PATCH] D110786: [GlobalISel] Extend G_SELECT of known condition combine to vectors.

[Amara Emerson via Phabricator via llvm-commits]

aemerson added inline comments.


================
Comment at: llvm/lib/CodeGen/GlobalISel/Utils.cpp:1019-1030
+Optional<APInt>
+llvm::isConstantOrConstantVector(MachineInstr &MI,
+                                 const MachineRegisterInfo &MRI) {
+  Register Def = MI.getOperand(0).getReg();
+  if (auto C = getIConstantVRegValWithLookThrough(Def, MRI))
+    return C->Value;
+  auto RegOrCst = getBuildVectorConstantSplat(MI, MRI);
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Actually this doesn't have the same meaning as the DAG counterpart. This one only checks for constant scalars or splats of scalars. I'll rename this to make it clear.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D110786/new/

https://reviews.llvm.org/D110786