[llvm] [SimplifyLibCalls] Constant fold nan libcall (PR #101459)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,41 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt < %s -passes=instcombine -S | FileCheck %s
+
+ at empty = private unnamed_addr constant [1 x i8] zeroinitializer, align 1
+ at dec = private unnamed_addr constant [2 x i8] c"1\00", align 1
+ at hex = private unnamed_addr constant [4 x i8] c"0xf\00", align 1
+
+define double @nan_empty() {
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arsenm wrote:

Check the undef/poison/null, non-constant cases? 

https://github.com/llvm/llvm-project/pull/101459