[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 +1,57 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
+; RUN: opt < %s -passes='sroa' -S | FileCheck %s
+define double @phi_with_nsz(double %x) "no-signed-zeros-fp-math" {
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arsenm wrote:

the correct form is "no-signed-zeros-fp-math"="true". The verifier should really check this (or we should start auto upgrading to drop the pointless bool value) 

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