[llvm] [GlobalIsel] Add G_SCMP and G_UCMP instructions (PR #98894)

[Matt Arsenault via llvm-commits]

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@@ -1544,6 +1544,26 @@ void MachineVerifier::verifyPreISelGenericInstruction(const MachineInstr *MI) {
 
     break;
   }
+  case TargetOpcode::G_SCMP:
+  case TargetOpcode::G_UCMP: {
+    LLT DstTy = MRI->getType(MI->getOperand(0).getReg());
+    LLT SrcTy = MRI->getType(MI->getOperand(1).getReg());
+    LLT SrcTy2 = MRI->getType(MI->getOperand(2).getReg());
+
+    if ((DstTy.isVector() != SrcTy.isVector()) ||
+        (DstTy.isVector() &&
+         DstTy.getElementCount() != SrcTy.getElementCount())) {
+      report("Generic vector scmp/ucmp must preserve number of lanes", MI);
+      break;
+    }
+
+    if (SrcTy != SrcTy2) {
+      report("Generic scmp/ucmp must have same input types", MI);
+      break;
+    }
+
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arsenm wrote:

Are pointers valid? 

https://github.com/llvm/llvm-project/pull/98894