[llvm] [VPlan] Manage instruction medata in VPlan. (PR #135272)

[via llvm-commits]

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@@ -1509,9 +1514,11 @@ void VPWidenSelectRecipe::execute(VPTransformState &State) {
   Value *Op1 = State.get(getOperand(2));
   Value *Sel = State.Builder.CreateSelect(Cond, Op0, Op1);
   State.set(this, Sel);
-  if (isa<FPMathOperator>(Sel))
-    applyFlags(*cast<Instruction>(Sel));
-  State.addMetadata(Sel, dyn_cast_or_null<Instruction>(getUnderlyingValue()));
+  if (auto *I = dyn_cast<Instruction>(Sel)) {
+    if (isa<FPMathOperator>(I))
+      applyFlags(*I);
+    applyMetadata(*I);
+  }
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ayalz wrote:

Independent, consistency nit: good to keep State.set() as the last operation of execute(), after fully finishing to build the new instruction/value, including applying its flags/metadata. Conceptually, flags and metadata could be folded into Builder.CreateSelect().

https://github.com/llvm/llvm-project/pull/135272