From 20f4f606525b223d509a88b7b05116fb2a77757b Mon Sep 17 00:00:00 2001 From: bassiounix Date: Sun, 5 Oct 2025 06:09:45 +0300 Subject: [PATCH] [libc][math] Refactor exp2f implementation to header-only in src/__support/math folder. --- libc/shared/math.h | 1 + libc/shared/math/exp2f.h | 23 ++++++++++++ libc/src/__support/math/CMakeLists.txt | 18 ++++++++++ .../exp2f_impl.h => __support/math/exp2f.h} | 22 ++++++------ libc/src/math/generic/CMakeLists.txt | 22 ++---------- libc/src/math/generic/exp2f.cpp | 4 +-- libc/src/math/generic/powf.cpp | 5 ++- libc/test/shared/CMakeLists.txt | 1 + libc/test/shared/shared_math_test.cpp | 1 + .../llvm-project-overlay/libc/BUILD.bazel | 36 +++++++++---------- 10 files changed, 80 insertions(+), 53 deletions(-) create mode 100644 libc/shared/math/exp2f.h rename libc/src/{math/generic/exp2f_impl.h => __support/math/exp2f.h} (94%) diff --git a/libc/shared/math.h b/libc/shared/math.h index 924d0cb4f3bfa..1262fa6f682d0 100644 --- a/libc/shared/math.h +++ b/libc/shared/math.h @@ -48,6 +48,7 @@ #include "math/exp10m1f.h" #include "math/exp10m1f16.h" #include "math/exp2.h" +#include "math/exp2f.h" #include "math/expf.h" #include "math/expf16.h" #include "math/frexpf.h" diff --git a/libc/shared/math/exp2f.h b/libc/shared/math/exp2f.h new file mode 100644 index 0000000000000..8c37cbb702e91 --- /dev/null +++ b/libc/shared/math/exp2f.h @@ -0,0 +1,23 @@ +//===-- Shared exp2f 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_EXP2F_H +#define LLVM_LIBC_SHARED_MATH_EXP2F_H + +#include "shared/libc_common.h" +#include "src/__support/math/exp2f.h" + +namespace LIBC_NAMESPACE_DECL { +namespace shared { + +using math::exp2f; + +} // namespace shared +} // namespace LIBC_NAMESPACE_DECL + +#endif // LLVM_LIBC_SHARED_MATH_EXP2F_H diff --git a/libc/src/__support/math/CMakeLists.txt b/libc/src/__support/math/CMakeLists.txt index 4130fdf02078b..203ebb4bf1760 100644 --- a/libc/src/__support/math/CMakeLists.txt +++ b/libc/src/__support/math/CMakeLists.txt @@ -735,6 +735,24 @@ add_header_library( libc.src.errno.errno ) +add_header_library( + exp2f + HDRS + exp2f.h + DEPENDS + .exp10f_utils + libc.src.__support.FPUtil.except_value_utils + libc.src.__support.FPUtil.fenv_impl + libc.src.__support.FPUtil.fp_bits + libc.src.__support.FPUtil.multiply_add + libc.src.__support.FPUtil.nearest_integer + libc.src.__support.FPUtil.polyeval + libc.src.__support.FPUtil.rounding_mode + libc.src.__support.macros.optimization + libc.src.__support.common + libc.src.errno.errno +) + add_header_library( exp10 HDRS diff --git a/libc/src/math/generic/exp2f_impl.h b/libc/src/__support/math/exp2f.h similarity index 94% rename from libc/src/math/generic/exp2f_impl.h rename to libc/src/__support/math/exp2f.h index b85bb1548019f..ef2aad051b8a9 100644 --- a/libc/src/math/generic/exp2f_impl.h +++ b/libc/src/__support/math/exp2f.h @@ -1,4 +1,4 @@ -//===-- Single-precision 2^x function -------------------------------------===// +//===-- Implementation header for exp2f -------------------------*- C++ -*-===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. @@ -6,9 +6,10 @@ // //===----------------------------------------------------------------------===// -#ifndef LLVM_LIBC_SRC_MATH_GENERIC_EXP2F_IMPL_H -#define LLVM_LIBC_SRC_MATH_GENERIC_EXP2F_IMPL_H +#ifndef LLVM_LIBC_SRC___SUPPORT_MATH_EXP2F_H +#define LLVM_LIBC_SRC___SUPPORT_MATH_EXP2F_H +#include "exp10f_utils.h" #include "src/__support/FPUtil/FEnvImpl.h" #include "src/__support/FPUtil/FPBits.h" #include "src/__support/FPUtil/PolyEval.h" @@ -20,12 +21,12 @@ #include "src/__support/macros/config.h" #include "src/__support/macros/optimization.h" // LIBC_UNLIKELY #include "src/__support/macros/properties/cpu_features.h" -#include "src/__support/math/exp10f_utils.h" namespace LIBC_NAMESPACE_DECL { -namespace generic { -LIBC_INLINE float exp2f(float x) { +namespace math { + +LIBC_INLINE static constexpr float exp2f(float x) { using FPBits = typename fputil::FPBits; FPBits xbits(x); @@ -120,8 +121,8 @@ LIBC_INLINE float exp2f(float x) { // of 2^mid. // kf = (hi + mid) * 2^5 = round(x * 2^5) - float kf; - int k; + float kf = 0; + int k = 0; #ifdef LIBC_TARGET_CPU_HAS_NEAREST_INT kf = fputil::nearest_integer(x * 32.0f); k = static_cast(kf); @@ -161,7 +162,8 @@ LIBC_INLINE float exp2f(float x) { return static_cast(fputil::multiply_add(p, dx_sq * mh, c1 * mh)); } -} // namespace generic +} // namespace math + } // namespace LIBC_NAMESPACE_DECL -#endif // LLVM_LIBC_SRC_MATH_GENERIC_EXP2F_IMPL_H +#endif // LLVM_LIBC_SRC___SUPPORT_MATH_EXP2F_H diff --git a/libc/src/math/generic/CMakeLists.txt b/libc/src/math/generic/CMakeLists.txt index 28ea475f09656..5738fe86f6c7b 100644 --- a/libc/src/math/generic/CMakeLists.txt +++ b/libc/src/math/generic/CMakeLists.txt @@ -1451,24 +1451,6 @@ add_entrypoint_object( libc.src.__support.math.exp2 ) -add_header_library( - exp2f_impl - HDRS - exp2f_impl.h - DEPENDS - libc.src.__support.FPUtil.except_value_utils - libc.src.__support.FPUtil.fenv_impl - libc.src.__support.FPUtil.fp_bits - libc.src.__support.FPUtil.multiply_add - libc.src.__support.FPUtil.nearest_integer - libc.src.__support.FPUtil.polyeval - libc.src.__support.FPUtil.rounding_mode - libc.src.__support.macros.optimization - libc.src.__support.math.exp10f_utils - libc.src.__support.common - libc.src.errno.errno -) - add_entrypoint_object( exp2f SRCS @@ -1476,7 +1458,7 @@ add_entrypoint_object( HDRS ../exp2f.h DEPENDS - .exp2f_impl + libc.src.__support.math.exp2f ) add_entrypoint_object( @@ -1659,8 +1641,8 @@ add_entrypoint_object( HDRS ../powf.h DEPENDS - .exp2f_impl libc.src.__support.math.exp10f + libc.src.__support.math.exp2f libc.src.__support.CPP.bit libc.src.__support.FPUtil.fenv_impl libc.src.__support.FPUtil.fp_bits diff --git a/libc/src/math/generic/exp2f.cpp b/libc/src/math/generic/exp2f.cpp index 60d6510f23699..3117f73b59bcf 100644 --- a/libc/src/math/generic/exp2f.cpp +++ b/libc/src/math/generic/exp2f.cpp @@ -9,10 +9,10 @@ #include "src/math/exp2f.h" #include "src/__support/common.h" // for LLVM_LIBC_FUNCTION #include "src/__support/macros/config.h" -#include "src/math/generic/exp2f_impl.h" +#include "src/__support/math/exp2f.h" namespace LIBC_NAMESPACE_DECL { -LLVM_LIBC_FUNCTION(float, exp2f, (float x)) { return generic::exp2f(x); } +LLVM_LIBC_FUNCTION(float, exp2f, (float x)) { return math::exp2f(x); } } // namespace LIBC_NAMESPACE_DECL diff --git a/libc/src/math/generic/powf.cpp b/libc/src/math/generic/powf.cpp index 12246e9878758..dd2b6aa788b9b 100644 --- a/libc/src/math/generic/powf.cpp +++ b/libc/src/math/generic/powf.cpp @@ -20,10 +20,9 @@ #include "src/__support/macros/optimization.h" // LIBC_UNLIKELY #include "src/__support/math/common_constants.h" // Lookup tables EXP_M1 and EXP_M2. #include "src/__support/math/exp10f.h" // Speedup for powf(10, y) = exp10f(y) +#include "src/__support/math/exp2f.h" // Speedup for powf(2, y) = exp2f(y) #include "src/__support/math/exp_constants.h" -#include "exp2f_impl.h" // Speedup for powf(2, y) = exp2f(y) - namespace LIBC_NAMESPACE_DECL { using fputil::DoubleDouble; @@ -779,7 +778,7 @@ LLVM_LIBC_FUNCTION(float, powf, (float x, float y)) { #ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS case 0x4000'0000: // x = 2.0f // pow(2, y) = exp2(y) - return generic::exp2f(y); + return math::exp2f(y); case 0x4120'0000: // x = 10.0f // pow(10, y) = exp10(y) return math::exp10f(y); diff --git a/libc/test/shared/CMakeLists.txt b/libc/test/shared/CMakeLists.txt index 040f6356b2577..dbc3889c76471 100644 --- a/libc/test/shared/CMakeLists.txt +++ b/libc/test/shared/CMakeLists.txt @@ -41,6 +41,7 @@ add_fp_unittest( libc.src.__support.math.erff libc.src.__support.math.exp libc.src.__support.math.exp2 + libc.src.__support.math.exp2f libc.src.__support.math.exp10 libc.src.__support.math.exp10f libc.src.__support.math.exp10f16 diff --git a/libc/test/shared/shared_math_test.cpp b/libc/test/shared/shared_math_test.cpp index ef2e7b8d71456..d118d96da69dd 100644 --- a/libc/test/shared/shared_math_test.cpp +++ b/libc/test/shared/shared_math_test.cpp @@ -62,6 +62,7 @@ TEST(LlvmLibcSharedMathTest, AllFloat) { EXPECT_FP_EQ(0x0p+0f, LIBC_NAMESPACE::shared::erff(0.0f)); EXPECT_FP_EQ(0x1p+0f, LIBC_NAMESPACE::shared::exp10f(0.0f)); EXPECT_FP_EQ(0x1p+0f, LIBC_NAMESPACE::shared::expf(0.0f)); + EXPECT_FP_EQ(0x1p+0f, LIBC_NAMESPACE::shared::exp2f(0.0f)); EXPECT_FP_EQ_ALL_ROUNDING(0.75f, LIBC_NAMESPACE::shared::frexpf(24.0f, &exponent)); diff --git a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel index e91e7c8aa7c86..00db514beaf34 100644 --- a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel +++ b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel @@ -2167,22 +2167,6 @@ libc_support_library( ], ) -libc_support_library( - name = "exp2f_impl", - hdrs = ["src/math/generic/exp2f_impl.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_macros_optimization", - ":__support_math_common_constants", - ":__support_math_exp10f_utils", - ], -) - libc_support_library( name = "__support_math_acos", hdrs = ["src/__support/math/acos.h"], @@ -2895,6 +2879,22 @@ libc_support_library( ], ) +libc_support_library( + name = "__support_math_exp2f", + hdrs = ["src/__support/math/exp2f.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_macros_optimization", + ":__support_math_common_constants", + ":__support_math_exp10f_utils", + ], +) + libc_support_library( name = "__support_math_exp10", hdrs = ["src/__support/math/exp10.h"], @@ -3676,7 +3676,7 @@ libc_math_function( libc_math_function( name = "exp2f", additional_deps = [ - ":exp2f_impl", + ":__support_math_exp2f", ], ) @@ -4511,7 +4511,7 @@ libc_math_function( ":__support_macros_optimization", ":__support_math_exp10f", ":__support_math_common_constants", - ":exp2f_impl", + ":__support_math_exp2f", ], )