[llvm] [InferAttrs] Handle roundeven like other libm functions (PR #170691)

[via llvm-commits]

https://github.com/valadaptive updated https://github.com/llvm/llvm-project/pull/170691

>From a1764913491e1c61094350e53a2729d6cda3235d Mon Sep 17 00:00:00 2001
From: valadaptive <valadaptive at protonmail.com>
Date: Thu, 4 Dec 2025 10:40:55 -0500
Subject: [PATCH] [InferAttrs] Handle roundeven like other libm functions

It was previously missing entirely. It behaves like floor, ceil, round,
and trunc, having no side effects.
---
 llvm/lib/Transforms/Utils/BuildLibCalls.cpp         | 3 +++
 llvm/test/Transforms/InferFunctionAttrs/annotate.ll | 9 +++++++++
 2 files changed, 12 insertions(+)

diff --git a/llvm/lib/Transforms/Utils/BuildLibCalls.cpp b/llvm/lib/Transforms/Utils/BuildLibCalls.cpp
index 02b73e85d783f..e6642cad189cd 100644
--- a/llvm/lib/Transforms/Utils/BuildLibCalls.cpp
+++ b/llvm/lib/Transforms/Utils/BuildLibCalls.cpp
@@ -1361,6 +1361,9 @@ bool llvm::inferNonMandatoryLibFuncAttrs(Function &F,
   case LibFunc_nearbyint:
   case LibFunc_nearbyintf:
   case LibFunc_nearbyintl:
+  case LibFunc_roundeven:
+  case LibFunc_roundevenf:
+  case LibFunc_roundevenl:
   case LibFunc_toascii:
   case LibFunc_trunc:
   case LibFunc_truncf:
diff --git a/llvm/test/Transforms/InferFunctionAttrs/annotate.ll b/llvm/test/Transforms/InferFunctionAttrs/annotate.ll
index 25a70a026a0b7..555262559e24d 100644
--- a/llvm/test/Transforms/InferFunctionAttrs/annotate.ll
+++ b/llvm/test/Transforms/InferFunctionAttrs/annotate.ll
@@ -918,6 +918,15 @@ declare float @roundf(float)
 ; CHECK: declare x86_fp80 @roundl(x86_fp80) [[ERRNOMEMONLY_NOFREE_NOUNWIND_WILLRETURN:#[0-9]+]]
 declare x86_fp80 @roundl(x86_fp80)
 
+; CHECK: declare double @roundeven(double) [[MEMNONE_NOFREE_NOUNWIND_WILLRETURN:#[0-9]+]]
+declare double @roundeven(double)
+
+; CHECK: declare float @roundevenf(float) [[MEMNONE_NOFREE_NOUNWIND_WILLRETURN:#[0-9]+]]
+declare float @roundevenf(float)
+
+; CHECK: declare x86_fp80 @roundevenl(x86_fp80) [[MEMNONE_NOFREE_NOUNWIND_WILLRETURN:#[0-9]+]]
+declare x86_fp80 @roundevenl(x86_fp80)
+
 ; CHECK: declare double @scalbln(double, i64) [[ERRNOMEMONLY_NOFREE_NOUNWIND_WILLRETURN:#[0-9]+]]
 declare double @scalbln(double, i64)