[llvm] [VPlan] Add VPInst::getNumOperandsForOpcode, use to verify in ctor (NFC) (PR #142284)

[via llvm-commits]

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@@ -722,7 +724,7 @@ TEST_F(VPBasicBlockTest, print) {
   VPBB1->setName("bb1");
 
   VPInstruction *I4 = new VPInstruction(Instruction::Mul, {I2, I1});
-  VPInstruction *I5 = new VPInstruction(Instruction::Ret, {I4});
+  VPInstruction *I5 = new VPInstruction(Instruction::Br, {I4});
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ayalz wrote:

Avoid checking return with a single operand? A VPInstruction with an Instruction opcode should retain the latter's number of operands, but that may require checking an underlying Instruction?

https://github.com/llvm/llvm-project/pull/142284