[llvm] [VPlan] Populate and use VPIRFlags from initial VPInstruction (NFC) (PR #168450)

[Florian Hahn via llvm-commits]

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@@ -2056,24 +2056,26 @@ bool VPIRFlags::flagsValidForOpcode(unsigned Opcode) const {
   switch (OpType) {
   case OperationType::OverflowingBinOp:
     return Opcode == Instruction::Add || Opcode == Instruction::Sub ||
-           Opcode == Instruction::Mul ||
+           Opcode == Instruction::Mul || Opcode == Instruction::Shl ||
            Opcode == VPInstruction::VPInstruction::CanonicalIVIncrementForPart;
   case OperationType::Trunc:
     return Opcode == Instruction::Trunc;
   case OperationType::DisjointOp:
     return Opcode == Instruction::Or;
   case OperationType::PossiblyExactOp:
-    return Opcode == Instruction::AShr;
+    return Opcode == Instruction::AShr || Opcode == Instruction::LShr ||
+           Opcode == Instruction::UDiv || Opcode == Instruction::SDiv;
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fhahn wrote:

Yep, I was looking for something similar before adding the function, but for most IR cases, dyn_cast/cast seems to work fine.

https://github.com/llvm/llvm-project/pull/168450