[llvm] [MachinePipeliner] Improve loop carried dependence analysis (PR #94185)

[Yuta Mukai via llvm-commits]

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@@ -1,14 +1,15 @@
 # RUN: llc -mtriple=hexagon -run-pass pipeliner -debug-only=pipeliner %s -o /dev/null 2>&1 -pipeliner-experimental-cg=true | FileCheck %s
 # REQUIRES: asserts
 
-# Test that the loop carried dependence check correctly identifies a recurrence
+# Test that it correctly recognizes that there is no loop carried dependence
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ytmukai wrote:

Yes, the loop carried dependence from the load to the store shoud be detected. But it is not made a candidate for the check because `addLoopCarriedDependences()` does not cover anything other than store-to-load dependencies. This is also fixed in #121907.

https://github.com/llvm/llvm-project/pull/94185