[llvm] [VPlan] Enable CSE of VPWidenPHIRecipe. (PR #207573)

[Owen Anderson via llvm-commits]

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@@ -1256,6 +1256,9 @@ getOpcodeOrIntrinsicID(const VPSingleDefRecipe *R) {
       .Case<VPInstruction, VPWidenRecipe, VPWidenCastRecipe, VPWidenGEPRecipe,
             VPReplicateRecipe>(
           [](auto *I) { return std::make_pair(false, I->getOpcode()); })
+      .Case([](const VPWidenPHIRecipe *I) {
+        return std::make_pair(true, Instruction::PHI);
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resistor wrote:

Confirmed locally that making this change fixes the crash I'm seeing.

https://github.com/llvm/llvm-project/pull/207573