[llvm] [SLP]Remove operands upon marking instruction for deletion. (PR #97409)

[Simon Pilgrim via llvm-commits]

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@@ -17344,14 +17370,11 @@ class HorizontalReduction {
         Value *ReducedSubTree =
             emitReduction(VectorizedRoot, Builder, ReduxWidth, TTI);
         if (ReducedSubTree->getType() != VL.front()->getType()) {
-          ReducedSubTree = Builder.CreateIntCast(
-              ReducedSubTree, VL.front()->getType(), any_of(VL, [&](Value *R) {
-                KnownBits Known = computeKnownBits(
-                    R, cast<Instruction>(ReductionOps.front().front())
-                           ->getModule()
-                           ->getDataLayout());
-                return !Known.isNonNegative();
-              }));
+          assert(ReducedSubTree->getType() != VL.front()->getType() &&
+                 "Expected different reduction type.");
+          ReducedSubTree =
+              Builder.CreateIntCast(ReducedSubTree, VL.front()->getType(),
+                                    *V.isSignedMinBitwidthRootNode());
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RKSimon wrote:

Why is it safe to directly dereference an optional?

https://github.com/llvm/llvm-project/pull/97409