[libc][math] Refactor bf16divl to header-only (llvm#181535)

Part of llvm#147386

in preparation for:
https://discourse.llvm.org/t/rfc-make-clang-builtin-math-functions-constexpr-with-llvm-libc-to-support-c-23-constexpr-math-functions/86450
Closes llvm#181025

Author: AbdallahRashed

libc/shared/math.h

@@ -34,6 +34,7 @@
 #include "math/bf16addf.h"
 #include "math/bf16addf128.h"
 #include "math/bf16divf.h"
+#include "math/bf16divl.h"
 #include "math/bf16fmaf.h"
 #include "math/canonicalize.h"
 #include "math/canonicalizebf16.h"

libc/shared/math/bf16divl.h

@@ -0,0 +1,23 @@
+//===-- Shared bf16divl function --------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SHARED_MATH_BF16DIVL_H
+#define LLVM_LIBC_SHARED_MATH_BF16DIVL_H
+
+#include "shared/libc_common.h"
+#include "src/__support/math/bf16divl.h"
+
+namespace LIBC_NAMESPACE_DECL {
+namespace shared {
+
+using math::bf16divl;
+
+} // namespace shared
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SHARED_MATH_BF16DIVL_H

libc/src/__support/math/CMakeLists.txt

@@ -440,6 +440,16 @@ add_header_library(
 )
 
 
+add_header_library(
+  bf16divl
+  HDRS
+    bf16divl.h
+  DEPENDS
+    libc.src.__support.FPUtil.bfloat16
+    libc.src.__support.FPUtil.generic.div
+    libc.src.__support.macros.config
+)
+
 add_header_library(
   cbrt
   HDRS

libc/src/__support/math/bf16divl.h

@@ -0,0 +1,26 @@
+//===-- Implementation header for bf16divl ----------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC___SUPPORT_MATH_BF16DIVL_H
+#define LLVM_LIBC_SRC___SUPPORT_MATH_BF16DIVL_H
+
+#include "src/__support/FPUtil/bfloat16.h"
+#include "src/__support/FPUtil/generic/div.h"
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+namespace math {
+
+LIBC_INLINE bfloat16 bf16divl(long double x, long double y) {
+  return fputil::generic::div<bfloat16>(x, y);
+}
+
+} // namespace math
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC___SUPPORT_MATH_BF16DIVL_H

libc/src/math/generic/CMakeLists.txt

@@ -5171,11 +5171,7 @@ add_entrypoint_object(
   HDRS
     ../bf16divl.h
   DEPENDS
-    libc.src.__support.common
-    libc.src.__support.FPUtil.bfloat16
-    libc.src.__support.FPUtil.generic.div
-    libc.src.__support.macros.config
-    libc.src.__support.macros.properties.types
+    libc.src.__support.math.bf16divl
 )
 
 add_entrypoint_object(

libc/src/math/generic/bf16divl.cpp

@@ -7,15 +7,12 @@
 //===----------------------------------------------------------------------===//
 
 #include "src/math/bf16divl.h"
-#include "src/__support/FPUtil/bfloat16.h"
-#include "src/__support/FPUtil/generic/div.h"
-#include "src/__support/common.h"
-#include "src/__support/macros/config.h"
+#include "src/__support/math/bf16divl.h"
 
 namespace LIBC_NAMESPACE_DECL {
 
 LLVM_LIBC_FUNCTION(bfloat16, bf16divl, (long double x, long double y)) {
-  return fputil::generic::div<bfloat16>(x, y);
+  return math::bf16divl(x, y);
 }
 
 } // namespace LIBC_NAMESPACE_DECL

libc/test/shared/CMakeLists.txt

@@ -30,6 +30,7 @@ add_fp_unittest(
     libc.src.__support.math.bf16addf
     libc.src.__support.math.bf16addf128
     libc.src.__support.math.bf16divf
+    libc.src.__support.math.bf16divl
     libc.src.__support.math.bf16fmaf
     libc.src.__support.math.canonicalize
     libc.src.__support.math.canonicalizebf16

libc/test/shared/shared_math_test.cpp

@@ -245,6 +245,7 @@ TEST(LlvmLibcSharedMathTest, AllFloat128) {
 TEST(LlvmLibcSharedMathTest, AllBFloat16) {
   EXPECT_FP_EQ(bfloat16(5.0), LIBC_NAMESPACE::shared::bf16add(2.0, 3.0));
   EXPECT_FP_EQ(bfloat16(2.0f), LIBC_NAMESPACE::shared::bf16divf(4.0f, 2.0f));
+  EXPECT_FP_EQ(bfloat16(2.0), LIBC_NAMESPACE::shared::bf16divl(6.0L, 3.0L));
 
   bfloat16 canonicalizebf16_cx = bfloat16(0.0);
   bfloat16 canonicalizebf16_x = bfloat16(0.0);

utils/bazel/llvm-project-overlay/libc/BUILD.bazel

@@ -2675,6 +2675,16 @@ libc_support_library(
     ],
 )
 
+libc_support_library(
+    name = "__support_math_bf16divl",
+    hdrs = ["src/__support/math/bf16divl.h"],
+    deps = [
+        ":__support_fputil_basic_operations",
+        ":__support_fputil_bfloat16",
+        ":__support_macros_config",
+    ],
+)
+
 libc_support_library(
     name = "__support_math_bf16fmaf",
     hdrs = ["src/__support/math/bf16fmaf.h"],
@@ -4568,6 +4578,11 @@ libc_math_function(
     additional_deps = [":__support_math_bf16addf128"],
 )
 
+libc_math_function(
+    name = "bf16divl",
+    additional_deps = [":__support_math_bf16divl"],
+)
+
 libc_math_function(
     name = "bf16fmaf",
     additional_deps = [":__support_math_bf16fmaf"],