[llvm] [MCP] Optimize copies when src is used during backward propagation (PR #111130)

[Matt Arsenault via llvm-commits]

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@@ -667,6 +707,26 @@ bool MachineCopyPropagation::hasOverlappingMultipleDef(
   return false;
 }
 
+/// Return true if it is safe to update the users of the source register of the
+/// copy.
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arsenm wrote:

Document parameters?

https://github.com/llvm/llvm-project/pull/111130