[llvm] [VPlan] Preserve trunc nuw/nsw in VPRecipeWithIRFlags (PR #144700)

[Luke Lau via llvm-commits]

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@@ -595,7 +595,7 @@ class VPSingleDefRecipe : public VPRecipeBase, public VPValue {
 class VPIRFlags {
   enum class OperationType : unsigned char {
     Cmp,
-    OverflowingBinOp,
+    WrappingOp,
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lukel97 wrote:

Yeah that crossed my mind too, I've added it in [0a7258a](https://github.com/llvm/llvm-project/pull/144700/commits/0a7258aabb95a811e450e97308d9e32c905b326b) and it seems to work well.

My only concern was the `VPWidenRecipe(unsigned VPDefOpcode, unsigned Opcode, ArrayRef<VPValue *> Operands, bool NUW, bool NSW, DebugLoc DL)` constructor but I think the `VPIRFlags::flagsValidForOpcode` check should catch any cases where a trunc opcode is passed into it.

https://github.com/llvm/llvm-project/pull/144700