[llvm] Merge sourcelocation in CSEMIRBuilder::getDominatingInstrForID. (PR #90922)

[Adrian Prantl via llvm-commits]

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@@ -99,6 +100,8 @@ class LegalizationArtifactCombiner {
       const LLT DstTy = MRI.getType(DstReg);
       if (isInstLegal({TargetOpcode::G_CONSTANT, {DstTy}})) {
         auto &CstVal = SrcMI->getOperand(1);
+        Builder.MergedLocation = DILocation::getMergedLocation(
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adrian-prantl wrote:

I don't think I like this solution of keeping global state in the MachineBuilder over threading it through the API.

https://github.com/llvm/llvm-project/pull/90922