[VPlan] Refine the constructor of VPWidenIntrinsicRecipe. nfc (#113890)

Infers member MayReadFromMemory, MayWriteToMemory, and
MayHaveSideEffects based on intrinsic attributes.

---------

Co-authored-by: Florian Hahn <[email protected]>

Author: Mel-Chen

llvm/lib/Transforms/Vectorize/VPlan.h

@@ -1688,13 +1688,18 @@ class VPWidenIntrinsicRecipe : public VPRecipeWithIRFlags {
 
   VPWidenIntrinsicRecipe(Intrinsic::ID VectorIntrinsicID,
                          ArrayRef<VPValue *> CallArguments, Type *Ty,
-                         bool MayReadFromMemory, bool MayWriteToMemory,
-                         bool MayHaveSideEffects, DebugLoc DL = {})
+                         DebugLoc DL = {})
       : VPRecipeWithIRFlags(VPDef::VPWidenIntrinsicSC, CallArguments),
-        VectorIntrinsicID(VectorIntrinsicID), ResultTy(Ty),
-        MayReadFromMemory(MayReadFromMemory),
-        MayWriteToMemory(MayWriteToMemory),
-        MayHaveSideEffects(MayHaveSideEffects) {}
+        VectorIntrinsicID(VectorIntrinsicID), ResultTy(Ty) {
+    LLVMContext &Ctx = Ty->getContext();
+    AttributeList Attrs = Intrinsic::getAttributes(Ctx, VectorIntrinsicID);
+    MemoryEffects ME = Attrs.getMemoryEffects();
+    MayReadFromMemory = ME.onlyWritesMemory();
+    MayWriteToMemory = ME.onlyReadsMemory();
+    MayHaveSideEffects = MayWriteToMemory ||
+                         !Attrs.hasFnAttr(Attribute::NoUnwind) ||
+                         !Attrs.hasFnAttr(Attribute::WillReturn);
+  }
 
   ~VPWidenIntrinsicRecipe() override = default;
 

llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp

@@ -1489,7 +1489,7 @@ static void transformRecipestoEVLRecipes(VPlan &Plan, VPValue &EVL) {
                 Ops.push_back(&EVL);
                 return new VPWidenIntrinsicRecipe(Intrinsic::vp_select, Ops,
                                                   TypeInfo.inferScalarType(Sel),
-                                                  false, false, false);
+                                                  Sel->getDebugLoc());
               })
 
               .Default([&](VPRecipeBase *R) { return nullptr; });