[llvm] [SROA] Propagate no-signed-zeros(nsz) fast-math flag on the phi node using function attribute (PR #83381)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,24 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -passes='default<O1>' -S < %s | FileCheck %s
+
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arsenm wrote:

Test name could use more elaboration, and a comment 

https://github.com/llvm/llvm-project/pull/83381