[llvm] [VPlan] Model cost of safe-divisor in VPlan (PR #154468)

[David Sherwood via llvm-commits]

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@@ -7949,6 +7949,7 @@ VPWidenRecipe *VPRecipeBuilder::tryToWiden(Instruction *I,
       VPValue *One =
           Plan.getOrAddLiveIn(ConstantInt::get(I->getType(), 1u, false));
       auto *SafeRHS = Builder.createSelect(Mask, Ops[1], One, I->getDebugLoc());
+      SafeRHS->setUnderlyingValue(I);
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david-arm wrote:

However, I'm happy to pull this into https://github.com/llvm/llvm-project/pull/152707 if we're happy with the potential impact of having the same underlying value for multiple recipes. It would reduce the scope of my PR to strictly divides. Any thoughts @fhahn?

https://github.com/llvm/llvm-project/pull/154468