[libc][math] Refactor fma implementation to header-only in src/__support/math folder.

[bassiounix]

Part of #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

[llvmbot]

@llvm/pr-subscribers-libc

Author: Muhammad Bassiouni (bassiounix)

Changes

Part of #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

---

Full diff: https://github.com/llvm/llvm-project/pull/163968.diff

9 Files Affected:

• (modified) libc/shared/math.h (+1)
• (added) libc/shared/math/fma.h (+23)
• (modified) libc/src/__support/math/CMakeLists.txt (+8)
• (added) libc/src/__support/math/fma.h (+27)
• (modified) libc/src/math/generic/CMakeLists.txt (+1-1)
• (modified) libc/src/math/generic/fma.cpp (+2-5)
• (modified) libc/test/shared/CMakeLists.txt (+1)
• (modified) libc/test/shared/shared_math_test.cpp (+1)
• (modified) utils/bazel/llvm-project-overlay/libc/BUILD.bazel (+11-3)

diff --git a/libc/shared/math.h b/libc/shared/math.h
index 874c2c0779adb..79ba2ea5aa6ff 100644
--- a/libc/shared/math.h
+++ b/libc/shared/math.h
@@ -57,6 +57,7 @@
 #include "math/expm1.h"
 #include "math/expm1f.h"
 #include "math/expm1f16.h"
+#include "math/fma.h"
 #include "math/frexpf.h"
 #include "math/frexpf128.h"
 #include "math/frexpf16.h"
diff --git a/libc/shared/math/fma.h b/libc/shared/math/fma.h
new file mode 100644
index 0000000000000..82f1dac61dda2
--- /dev/null
+++ b/libc/shared/math/fma.h
@@ -0,0 +1,23 @@
+//===-- Shared fma 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_FMA_H
+#define LLVM_LIBC_SHARED_MATH_FMA_H
+
+#include "shared/libc_common.h"
+#include "src/__support/math/fma.h"
+
+namespace LIBC_NAMESPACE_DECL {
+namespace shared {
+
+using math::fma;
+
+} // namespace shared
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SHARED_MATH_FMA_H
diff --git a/libc/src/__support/math/CMakeLists.txt b/libc/src/__support/math/CMakeLists.txt
index 0cae228d7f10f..1911481d0649e 100644
--- a/libc/src/__support/math/CMakeLists.txt
+++ b/libc/src/__support/math/CMakeLists.txt
@@ -593,6 +593,14 @@ add_header_library(
     libc.src.__support.math.exp10_float16_constants
 )
 
+add_header_library(
+  fma
+  HDRS
+    fma.h
+  DEPENDS
+    libc.src.__support.FPUtil.fma
+)
+
 add_header_library(
   frexpf128
   HDRS
diff --git a/libc/src/__support/math/fma.h b/libc/src/__support/math/fma.h
new file mode 100644
index 0000000000000..d996610167a19
--- /dev/null
+++ b/libc/src/__support/math/fma.h
@@ -0,0 +1,27 @@
+//===-- Implementation header for fma ---------------------------*- 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_FMA_H
+#define LLVM_LIBC_SRC___SUPPORT_MATH_FMA_H
+
+#include "src/__support/FPUtil/FMA.h"
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+namespace math {
+
+LIBC_INLINE static double fma(double x, double y, double z) {
+  return fputil::fma<double>(x, y, z);
+}
+
+} // namespace math
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC___SUPPORT_MATH_FMA_H
diff --git a/libc/src/math/generic/CMakeLists.txt b/libc/src/math/generic/CMakeLists.txt
index b13da9770dc69..7103c6947eba0 100644
--- a/libc/src/math/generic/CMakeLists.txt
+++ b/libc/src/math/generic/CMakeLists.txt
@@ -4722,7 +4722,7 @@ add_entrypoint_object(
   HDRS
     ../fma.h
   DEPENDS
-    libc.src.__support.FPUtil.fma
+    libc.src.__support.math.fma
 )
 
 add_entrypoint_object(
diff --git a/libc/src/math/generic/fma.cpp b/libc/src/math/generic/fma.cpp
index 2ea4ae9961150..3ccdb78846e34 100644
--- a/libc/src/math/generic/fma.cpp
+++ b/libc/src/math/generic/fma.cpp
@@ -7,15 +7,12 @@
 //===----------------------------------------------------------------------===//
 
 #include "src/math/fma.h"
-#include "src/__support/common.h"
-
-#include "src/__support/FPUtil/FMA.h"
-#include "src/__support/macros/config.h"
+#include "src/__support/math/fma.h"
 
 namespace LIBC_NAMESPACE_DECL {
 
 LLVM_LIBC_FUNCTION(double, fma, (double x, double y, double z)) {
-  return fputil::fma<double>(x, y, z);
+  return math::fma(x, y, z);
 }
 
 } // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/test/shared/CMakeLists.txt b/libc/test/shared/CMakeLists.txt
index bfcac7884e646..cd4b5ec75f876 100644
--- a/libc/test/shared/CMakeLists.txt
+++ b/libc/test/shared/CMakeLists.txt
@@ -53,6 +53,7 @@ add_fp_unittest(
     libc.src.__support.math.exp10f16
     libc.src.__support.math.expf
     libc.src.__support.math.expf16
+    libc.src.__support.math.fma
     libc.src.__support.math.frexpf
     libc.src.__support.math.frexpf128
     libc.src.__support.math.frexpf16
diff --git a/libc/test/shared/shared_math_test.cpp b/libc/test/shared/shared_math_test.cpp
index 3369cb5e2cf03..7357e24603004 100644
--- a/libc/test/shared/shared_math_test.cpp
+++ b/libc/test/shared/shared_math_test.cpp
@@ -90,6 +90,7 @@ TEST(LlvmLibcSharedMathTest, AllDouble) {
   EXPECT_FP_EQ(0x1p+0, LIBC_NAMESPACE::shared::exp2(0.0));
   EXPECT_FP_EQ(0x1p+0, LIBC_NAMESPACE::shared::exp10(0.0));
   EXPECT_FP_EQ(0x0p+0, LIBC_NAMESPACE::shared::expm1(0.0));
+  EXPECT_FP_EQ(0x0p+0, LIBC_NAMESPACE::shared::fma(0.0, 0.0, 0.0));
 }
 
 #ifdef LIBC_TYPES_HAS_FLOAT128
diff --git a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
index 7c98fc7d53796..1902b43216a7c 100644
--- a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
@@ -2791,6 +2791,14 @@ libc_support_library(
     ],
 )
 
+libc_support_library(
+    name = "__support_math_fma",
+    hdrs = ["src/__support/math/fma.h"],
+    deps = [
+        ":__support_fputil_fma",
+    ],
+)
+
 libc_support_library(
     name = "__support_math_frexpf128",
     hdrs = ["src/__support/math/frexpf128.h"],
@@ -3093,15 +3101,15 @@ libc_support_library(
     name = "__support_math_expm1f16",
     hdrs = ["src/__support/math/expm1f16.h"],
     deps = [
+        ":__support_fputil_except_value_utils",
         ":__support_fputil_fma",
         ":__support_fputil_multiply_add",
         ":__support_fputil_nearest_integer",
         ":__support_fputil_polyeval",
         ":__support_fputil_rounding_mode",
-        ":__support_fputil_except_value_utils",
         ":__support_macros_optimization",
         ":__support_macros_properties_cpu_features",
-        ":__support_math_expxf16_utils"
+        ":__support_math_expxf16_utils",
     ],
 )
 
@@ -4001,7 +4009,7 @@ libc_math_function(name = "floorf16")
 libc_math_function(
     name = "fma",
     additional_deps = [
-        ":__support_fputil_fma",
+        ":__support_math_fma",
     ],
 )
 

[bassiounix]

Merge activity

• Mar 17, 7:22 PM UTC: Graphite rebased this pull request as part of a merge.