[llvm] [InstCombine] Transform (fcmp + fadd + sel) into (fcmp + sel + fadd) (PR #106492)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,634 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt < %s -passes=instcombine -S | FileCheck %s
+
+; fcmp OGT + fadd + sel => fcmp OGT + sel => fmaxnum
+
+define float @test_fcmp_ogt_fadd_select_constant(float %in) {
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arsenm wrote:

This case fails alive: https://alive2.llvm.org/ce/z/_h-8Lw

You can't preserve the nnan unless it was also present on the fadd and fcmp 

https://github.com/llvm/llvm-project/pull/106492