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

[Florian Hahn via llvm-commits]

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@@ -706,13 +706,15 @@ TEST_F(VPBasicBlockTest, reassociateBlocks) {
 
 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
 TEST_F(VPBasicBlockTest, print) {
-  VPInstruction *TC = new VPInstruction(Instruction::Add, {});
+  VPInstruction *TC = new VPInstruction(Instruction::PHI, {});
   VPlan &Plan = getPlan(TC);
+  IntegerType *Int32 = IntegerType::get(C, 32);
+  VPValue *Val = Plan.getOrAddLiveIn(ConstantInt::get(Int32, 1));
   VPBasicBlock *VPBB0 = Plan.getEntry();
   VPBB0->appendRecipe(TC);
 
-  VPInstruction *I1 = new VPInstruction(Instruction::Add, {});
-  VPInstruction *I2 = new VPInstruction(Instruction::Sub, {I1});
+  VPInstruction *I1 = new VPInstruction(Instruction::Add, {Val, Val});
+  VPInstruction *I2 = new VPInstruction(Instruction::Sub, {I1, Val});
   VPInstruction *I3 = new VPInstruction(Instruction::Br, {I1, I2});
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fhahn wrote:

Yep, this just creates artificial VPInstructions to test printing, the ocpodes don't really matter, other than checking.

We should probably tighten down which kinds of opcodes are supported for VPInstruction

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