[llvm] [ConstantFolding] Add ilogb in isMathLibCallNoop (PR #122582)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,13 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt < %s -O1 -S | FileCheck %s
+
+define i32 @ilogb_const1() {
+; CHECK-LABEL: define noundef i32 @ilogb_const1(
+; CHECK-SAME: ) local_unnamed_addr #[[ATTR0:[0-9]+]] {
+; CHECK-NEXT:    ret i32 2
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arsenm wrote:

Attribute noise will disappear with this reduced to running instsimplify 

https://github.com/llvm/llvm-project/pull/122582