[llvm] [DebugInfo] Don't apply is_stmt on MBB branches that preserve lines (PR #108251)

[Jeremy Morse via llvm-commits]

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@@ -0,0 +1,62 @@
+;; Checks that when an instruction at the start of a BasicBlock has the same
+;; DebugLoc as the instruction at the end of the previous BasicBlock, we add
+;; is_stmt to the new line, to ensure that we still step on it if we arrive from
+;; a BasicBlock other than the immediately preceding one, unless all known
+;; predecessor BasicBlocks end with the same line.
+
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jmorse wrote:

Convention is to put the RUN lines above this IIRC? Either way I endorse every test having an explanation of what it's testing.

https://github.com/llvm/llvm-project/pull/108251