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

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,67 @@
+# This test checks to make sure that when an instruction (%35 in the test) is 
+# moved due to matching a result of a fold of two other instructions
+# (%16, and %17 in the test) in the legalizer, the DILocation of the 
+# instruction that is moved (%35) is updated appropriately.
+
+# RUN: llc %s -O0 --start-before=legalizer --stop-after=legalizer -o - | FileCheck %s 
+# CHECK-NOT: %35:_(s32) = G_CONSTANT i32 0, debug-location !71
+# CHECK: %35:_(s32) = G_CONSTANT i32 0, debug-location !DILocation(line: 0,
+--- |
+  source_filename = "/tmp/main.ll"
+  target datalayout = "e-m:o-i64:64-i128:128-n32:64-S128"
+  target triple = "arm64-apple-macosx14.0.0"
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arsenm wrote:

Can drop this 

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