[llvm] [BFI] Preserve zero-mass exits in solveIrreducibleMass (PR #218140)

[Alexis Engelke via llvm-commits]

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@@ -0,0 +1,60 @@
+; test for https://github.com/llvm/llvm-project/issues/217740
+
+; REQUIRES: asserts
+
+; RUN: llc -O3 -o /dev/null %s
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aengelke wrote:

Restrict passes to just require/print the analysis. Also remove requires: asserts, check output and preferably use update-test-checks.

https://github.com/llvm/llvm-project/pull/218140