[llvm] [DAGCombiner] Merge debug locations when combining stores (PR #225358)

[Jeremy Morse via llvm-commits]

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@@ -0,0 +1,178 @@
+; RUN: llc -O2 -mtriple=x86_64-unknown-linux-gnu -verify-machineinstrs -stop-after=finalize-isel -o - %s | FileCheck %s
+
+;; Consecutive stores combined into a single store must merge their locations,
+;; rather than attributing all effects to the lowest-addressed store's scope.
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jmorse wrote:

I feel this is good coverage; but the comments on each function are sufficiently abstract that it becomes a little difficult to work out exactly what they're testing, would you be able to make them a bit more precise? (Comments inline).

https://github.com/llvm/llvm-project/pull/225358