[llvm] [SimplifyCFG] Set branch weights when merging conditional store to address (PR #154841)

[Mircea Trofin via llvm-commits]

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@@ -203,6 +203,8 @@ static cl::opt<unsigned> MaxJumpThreadingLiveBlocks(
     cl::desc("Limit number of blocks a define in a threaded block is allowed "
              "to be live in"));
 
+extern cl::opt<bool> ProfcheckDisableMetadataFixes;
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mtrofin wrote:

It's solely for a one-off ablation test I want to do at the end of this, to evaluate the performance impact of improving !prof propagation, after which I'll remove it. It's false by default. 

https://github.com/llvm/llvm-project/pull/154841