[llvm] [VPlan] Use VPInstructionWithType for uniform casts. (PR #140623)

[Luke Lau via llvm-commits]

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@@ -1067,8 +1070,9 @@ class VPInstructionWithType : public VPInstruction {
 public:
   VPInstructionWithType(unsigned Opcode, ArrayRef<VPValue *> Operands,
                         Type *ResultTy, const VPIRFlags &Flags, DebugLoc DL,
-                        const Twine &Name = "")
-      : VPInstruction(Opcode, Operands, Flags, DL, Name), ResultTy(ResultTy) {}
+                        bool SingleScalar = false, const Twine &Name = "")
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lukel97 wrote:

Nit, should this match the VPInstruction arg name?
```suggestion
                        bool IsSingleScalar = false, const Twine &Name = "")
```

https://github.com/llvm/llvm-project/pull/140623