[libc] [llvm] [libc][math] Refactor expf16 implementation to header-only in src/__support/math folder. (PR #147428)
Muhammad Bassiouni via llvm-commits
llvm-commits at lists.llvm.org
Tue Jul 8 09:20:05 PDT 2025
https://github.com/bassiounix updated https://github.com/llvm/llvm-project/pull/147428
>From 8a9ca87fda767b0463be195665690208a1f26377 Mon Sep 17 00:00:00 2001
From: bassiounix <muhammad.m.bassiouni at gmail.com>
Date: Tue, 8 Jul 2025 02:56:22 +0300
Subject: [PATCH 1/5] [libc][math] Refactor expf16 implementation to
header-only in src/__support/math folder.
---
libc/shared/math.h | 1 +
libc/shared/math/expf16.h | 23 ++++
libc/src/__support/math/CMakeLists.txt | 28 +++++
.../__support/math/exp_float16_constants.h | 38 ++++++
libc/src/__support/math/expf16.h | 116 ++++++++++++++++++
libc/src/math/generic/CMakeLists.txt | 14 +--
libc/src/math/generic/expf16.cpp | 115 +----------------
.../llvm-project-overlay/libc/BUILD.bazel | 29 +++++
8 files changed, 239 insertions(+), 125 deletions(-)
create mode 100644 libc/shared/math/expf16.h
create mode 100644 libc/src/__support/math/exp_float16_constants.h
create mode 100644 libc/src/__support/math/expf16.h
diff --git a/libc/shared/math.h b/libc/shared/math.h
index 4ddc29c7ae834..9db53b69041d0 100644
--- a/libc/shared/math.h
+++ b/libc/shared/math.h
@@ -12,5 +12,6 @@
#include "libc_common.h"
#include "math/expf.h"
+#include "math/expf16.h"
#endif // LLVM_LIBC_SHARED_MATH_H
diff --git a/libc/shared/math/expf16.h b/libc/shared/math/expf16.h
new file mode 100644
index 0000000000000..4e6ab78b26467
--- /dev/null
+++ b/libc/shared/math/expf16.h
@@ -0,0 +1,23 @@
+//===-- Shared expf16 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_EXPF16_H
+#define LLVM_LIBC_SHARED_MATH_EXPF16_H
+
+#include "shared/libc_common.h"
+#include "src/__support/math/expf16.h"
+
+namespace LIBC_NAMESPACE_DECL {
+namespace shared {
+
+using math::expf16;
+
+} // namespace shared
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SHARED_MATH_EXPF16_H
diff --git a/libc/src/__support/math/CMakeLists.txt b/libc/src/__support/math/CMakeLists.txt
index 66c1d19a1cab0..6d4d548f2e48f 100644
--- a/libc/src/__support/math/CMakeLists.txt
+++ b/libc/src/__support/math/CMakeLists.txt
@@ -22,3 +22,31 @@ add_header_library(
libc.src.__support.macros.config
libc.src.__support.macros.optimization
)
+
+add_header_library(
+ exp_float16_constants
+ HDRS
+ exp_float16_constants.h
+ DEPENDS
+ libc.src.__support.FPUtil.except_value_utils
+)
+
+add_header_library(
+ expf16
+ HDRS
+ expf16.h
+ DEPENDS
+ .expxf16
+ libc.hdr.errno_macros
+ libc.hdr.fenv_macros
+ libc.src.__support.CPP.array
+ libc.src.__support.FPUtil.cast
+ 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
+)
diff --git a/libc/src/__support/math/exp_float16_constants.h b/libc/src/__support/math/exp_float16_constants.h
new file mode 100644
index 0000000000000..9c3aa05e9551c
--- /dev/null
+++ b/libc/src/__support/math/exp_float16_constants.h
@@ -0,0 +1,38 @@
+//===-- High and Low Excepts for expf16 functions ---------------*- 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_EXP_FLOAT16_CONSTANTS_H
+#define LLVM_LIBC_SRC___SUPPORT_MATH_EXP_FLOAT16_CONSTANTS_H
+
+#include "src/__support/FPUtil/except_value_utils.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+#ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
+static constexpr fputil::ExceptValues<float16, 2> EXPF16_EXCEPTS_LO = {{
+ // (input, RZ output, RU offset, RD offset, RN offset)
+ // x = 0x1.de4p-8, expf16(x) = 0x1.01cp+0 (RZ)
+ {0x1f79U, 0x3c07U, 1U, 0U, 0U},
+ // x = 0x1.73cp-6, expf16(x) = 0x1.05cp+0 (RZ)
+ {0x25cfU, 0x3c17U, 1U, 0U, 0U},
+}};
+
+static constexpr fputil::ExceptValues<float16, 3> EXPF16_EXCEPTS_HI = {{
+ // (input, RZ output, RU offset, RD offset, RN offset)
+ // x = 0x1.c34p+0, expf16(x) = 0x1.74cp+2 (RZ)
+ {0x3f0dU, 0x45d3U, 1U, 0U, 1U},
+ // x = -0x1.488p-5, expf16(x) = 0x1.ebcp-1 (RZ)
+ {0xa922U, 0x3bafU, 1U, 0U, 0U},
+ // x = -0x1.55p-5, expf16(x) = 0x1.ebp-1 (RZ)
+ {0xa954U, 0x3bacU, 1U, 0U, 0U},
+}};
+#endif // !LIBC_MATH_HAS_SKIP_ACCURATE_PASS
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC___SUPPORT_MATH_EXP_FLOAT16_CONSTANTS_H
diff --git a/libc/src/__support/math/expf16.h b/libc/src/__support/math/expf16.h
new file mode 100644
index 0000000000000..29a8e44d373f5
--- /dev/null
+++ b/libc/src/__support/math/expf16.h
@@ -0,0 +1,116 @@
+//===-- Implementation header for expf16 ------------------------*- 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_EXPF16_H
+#define LLVM_LIBC_SRC___SUPPORT_MATH_EXPF16_H
+
+#include "exp_float16_constants.h"
+
+#include "hdr/errno_macros.h"
+#include "src/math/generic/expxf16.h"
+#include "hdr/fenv_macros.h"
+#include "src/__support/common.h"
+#include "src/__support/FPUtil/FEnvImpl.h"
+#include "src/__support/FPUtil/FPBits.h"
+#include "src/__support/FPUtil/PolyEval.h"
+#include "src/__support/FPUtil/cast.h"
+#include "src/__support/FPUtil/rounding_mode.h"
+#include "src/__support/macros/optimization.h"
+#include "src/__support/macros/config.h"
+#include "src/__support/FPUtil/except_value_utils.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+namespace math {
+
+static constexpr float16 expf16(float16 x) {
+ using FPBits = fputil::FPBits<float16>;
+ FPBits x_bits(x);
+
+ uint16_t x_u = x_bits.uintval();
+ uint16_t x_abs = x_u & 0x7fffU;
+
+ // When 0 < |x| <= 2^(-5), or |x| >= 12, or x is NaN.
+ if (LIBC_UNLIKELY(x_abs <= 0x2800U || x_abs >= 0x4a00U)) {
+ // exp(NaN) = NaN
+ if (x_bits.is_nan()) {
+ if (x_bits.is_signaling_nan()) {
+ fputil::raise_except_if_required(FE_INVALID);
+ return FPBits::quiet_nan().get_val();
+ }
+
+ return x;
+ }
+
+ // When x >= 12.
+ if (x_bits.is_pos() && x_abs >= 0x4a00U) {
+ // exp(+inf) = +inf
+ if (x_bits.is_inf())
+ return FPBits::inf().get_val();
+
+ switch (fputil::quick_get_round()) {
+ case FE_TONEAREST:
+ case FE_UPWARD:
+ fputil::set_errno_if_required(ERANGE);
+ fputil::raise_except_if_required(FE_OVERFLOW);
+ return FPBits::inf().get_val();
+ default:
+ return FPBits::max_normal().get_val();
+ }
+ }
+
+ // When x <= -18.
+ if (x_u >= 0xcc80U) {
+ // exp(-inf) = +0
+ if (x_bits.is_inf())
+ return FPBits::zero().get_val();
+
+ fputil::set_errno_if_required(ERANGE);
+ fputil::raise_except_if_required(FE_UNDERFLOW | FE_INEXACT);
+
+ switch (fputil::quick_get_round()) {
+ case FE_UPWARD:
+ return FPBits::min_subnormal().get_val();
+ default:
+ return FPBits::zero().get_val();
+ }
+ }
+
+ // When 0 < |x| <= 2^(-5).
+ if (x_abs <= 0x2800U && !x_bits.is_zero()) {
+#ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
+ if (auto r = EXPF16_EXCEPTS_LO.lookup(x_u); LIBC_UNLIKELY(r.has_value()))
+ return r.value();
+#endif // !LIBC_MATH_HAS_SKIP_ACCURATE_PASS
+
+ float xf = x;
+ // Degree-3 minimax polynomial generated by Sollya with the following
+ // commands:
+ // > display = hexadecimal;
+ // > P = fpminimax(expm1(x)/x, 2, [|SG...|], [-2^-5, 2^-5]);
+ // > 1 + x * P;
+ return fputil::cast<float16>(
+ fputil::polyeval(xf, 0x1p+0f, 0x1p+0f, 0x1.0004p-1f, 0x1.555778p-3f));
+ }
+ }
+
+#ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
+ if (auto r = EXPF16_EXCEPTS_HI.lookup(x_u); LIBC_UNLIKELY(r.has_value()))
+ return r.value();
+#endif // !LIBC_MATH_HAS_SKIP_ACCURATE_PASS
+
+ // exp(x) = exp(hi + mid) * exp(lo)
+ auto [exp_hi_mid, exp_lo] = exp_range_reduction(x);
+ return fputil::cast<float16>(exp_hi_mid * exp_lo);
+}
+
+} // namespace math
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC___SUPPORT_MATH_EXPF16_H
diff --git a/libc/src/math/generic/CMakeLists.txt b/libc/src/math/generic/CMakeLists.txt
index fd1e6c0d648aa..8d15c2879a8bf 100644
--- a/libc/src/math/generic/CMakeLists.txt
+++ b/libc/src/math/generic/CMakeLists.txt
@@ -1332,19 +1332,7 @@ add_entrypoint_object(
HDRS
../expf16.h
DEPENDS
- .expxf16
- libc.hdr.errno_macros
- libc.hdr.fenv_macros
- libc.src.__support.CPP.array
- libc.src.__support.FPUtil.cast
- 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.expf
)
add_entrypoint_object(
diff --git a/libc/src/math/generic/expf16.cpp b/libc/src/math/generic/expf16.cpp
index 1af9b3ec9ad6e..ad213e237f021 100644
--- a/libc/src/math/generic/expf16.cpp
+++ b/libc/src/math/generic/expf16.cpp
@@ -7,120 +7,11 @@
//===----------------------------------------------------------------------===//
#include "src/math/expf16.h"
-#include "expxf16.h"
-#include "hdr/errno_macros.h"
-#include "hdr/fenv_macros.h"
-#include "src/__support/FPUtil/FEnvImpl.h"
-#include "src/__support/FPUtil/FPBits.h"
-#include "src/__support/FPUtil/PolyEval.h"
-#include "src/__support/FPUtil/cast.h"
-#include "src/__support/FPUtil/except_value_utils.h"
-#include "src/__support/FPUtil/rounding_mode.h"
-#include "src/__support/common.h"
-#include "src/__support/macros/config.h"
-#include "src/__support/macros/optimization.h"
-namespace LIBC_NAMESPACE_DECL {
-
-#ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
-static constexpr fputil::ExceptValues<float16, 2> EXPF16_EXCEPTS_LO = {{
- // (input, RZ output, RU offset, RD offset, RN offset)
- // x = 0x1.de4p-8, expf16(x) = 0x1.01cp+0 (RZ)
- {0x1f79U, 0x3c07U, 1U, 0U, 0U},
- // x = 0x1.73cp-6, expf16(x) = 0x1.05cp+0 (RZ)
- {0x25cfU, 0x3c17U, 1U, 0U, 0U},
-}};
-
-static constexpr fputil::ExceptValues<float16, 3> EXPF16_EXCEPTS_HI = {{
- // (input, RZ output, RU offset, RD offset, RN offset)
- // x = 0x1.c34p+0, expf16(x) = 0x1.74cp+2 (RZ)
- {0x3f0dU, 0x45d3U, 1U, 0U, 1U},
- // x = -0x1.488p-5, expf16(x) = 0x1.ebcp-1 (RZ)
- {0xa922U, 0x3bafU, 1U, 0U, 0U},
- // x = -0x1.55p-5, expf16(x) = 0x1.ebp-1 (RZ)
- {0xa954U, 0x3bacU, 1U, 0U, 0U},
-}};
-#endif // !LIBC_MATH_HAS_SKIP_ACCURATE_PASS
-
-LLVM_LIBC_FUNCTION(float16, expf16, (float16 x)) {
- using FPBits = fputil::FPBits<float16>;
- FPBits x_bits(x);
-
- uint16_t x_u = x_bits.uintval();
- uint16_t x_abs = x_u & 0x7fffU;
-
- // When 0 < |x| <= 2^(-5), or |x| >= 12, or x is NaN.
- if (LIBC_UNLIKELY(x_abs <= 0x2800U || x_abs >= 0x4a00U)) {
- // exp(NaN) = NaN
- if (x_bits.is_nan()) {
- if (x_bits.is_signaling_nan()) {
- fputil::raise_except_if_required(FE_INVALID);
- return FPBits::quiet_nan().get_val();
- }
-
- return x;
- }
-
- // When x >= 12.
- if (x_bits.is_pos() && x_abs >= 0x4a00U) {
- // exp(+inf) = +inf
- if (x_bits.is_inf())
- return FPBits::inf().get_val();
+#include "src/__support/math/expf16.h"
- switch (fputil::quick_get_round()) {
- case FE_TONEAREST:
- case FE_UPWARD:
- fputil::set_errno_if_required(ERANGE);
- fputil::raise_except_if_required(FE_OVERFLOW);
- return FPBits::inf().get_val();
- default:
- return FPBits::max_normal().get_val();
- }
- }
-
- // When x <= -18.
- if (x_u >= 0xcc80U) {
- // exp(-inf) = +0
- if (x_bits.is_inf())
- return FPBits::zero().get_val();
-
- fputil::set_errno_if_required(ERANGE);
- fputil::raise_except_if_required(FE_UNDERFLOW | FE_INEXACT);
-
- switch (fputil::quick_get_round()) {
- case FE_UPWARD:
- return FPBits::min_subnormal().get_val();
- default:
- return FPBits::zero().get_val();
- }
- }
-
- // When 0 < |x| <= 2^(-5).
- if (x_abs <= 0x2800U && !x_bits.is_zero()) {
-#ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
- if (auto r = EXPF16_EXCEPTS_LO.lookup(x_u); LIBC_UNLIKELY(r.has_value()))
- return r.value();
-#endif // !LIBC_MATH_HAS_SKIP_ACCURATE_PASS
-
- float xf = x;
- // Degree-3 minimax polynomial generated by Sollya with the following
- // commands:
- // > display = hexadecimal;
- // > P = fpminimax(expm1(x)/x, 2, [|SG...|], [-2^-5, 2^-5]);
- // > 1 + x * P;
- return fputil::cast<float16>(
- fputil::polyeval(xf, 0x1p+0f, 0x1p+0f, 0x1.0004p-1f, 0x1.555778p-3f));
- }
- }
-
-#ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
- if (auto r = EXPF16_EXCEPTS_HI.lookup(x_u); LIBC_UNLIKELY(r.has_value()))
- return r.value();
-#endif // !LIBC_MATH_HAS_SKIP_ACCURATE_PASS
+namespace LIBC_NAMESPACE_DECL {
- // exp(x) = exp(hi + mid) * exp(lo)
- auto [exp_hi_mid, exp_lo] = exp_range_reduction(x);
- return fputil::cast<float16>(exp_hi_mid * exp_lo);
-}
+LLVM_LIBC_FUNCTION(float16, expf16, (float16 x)) { return math::expf16(x); }
} // namespace LIBC_NAMESPACE_DECL
diff --git a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
index 2484a2f1e2bd7..efba1eb640eb8 100644
--- a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
@@ -2096,6 +2096,34 @@ libc_support_library(
],
)
+libc_support_library(
+ name = "__support_math_exp_float16_constants",
+ hdrs = ["src/__support/math/exp_float16_constants.h"],
+ deps = [
+ ":__support_FPUtil_except_value_utils"
+ ],
+)
+
+libc_support_library(
+ name = "__support_math_expf16",
+ hdrs = ["src/__support/math/expf16.h"],
+ deps = [
+ ":__support_common",
+ ":hdr_errno_macros",
+ ":hdr_fenv_macros",
+ ":__support_cpp_array",
+ ":__support_fputil_cast",
+ ":__support_fputil_except_value_utils",
+ ":__support_fputil_fenv_impl",
+ ":__support_fputil_fp_bits",
+ ":__support_fputil_multiply_add",
+ ":__support_fputil_nearest_integer",
+ ":__support_fputil_polyeval",
+ ":__support_fputil_rounding_mode",
+ ":__support_macros_optimization",
+ ],
+)
+
############################### complex targets ################################
libc_function(
@@ -2701,6 +2729,7 @@ libc_math_function(
libc_math_function(
name = "expf16",
additional_deps = [
+ ":__support_math_expf16",
":expxf16",
],
)
>From b22f973fbd649092b582649b684ed791a8464e39 Mon Sep 17 00:00:00 2001
From: bassiounix <muhammad.m.bassiouni at gmail.com>
Date: Tue, 8 Jul 2025 03:11:39 +0300
Subject: [PATCH 2/5] fix code style
---
libc/src/__support/math/expf16.h | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/libc/src/__support/math/expf16.h b/libc/src/__support/math/expf16.h
index 29a8e44d373f5..7fd8ce0173f59 100644
--- a/libc/src/__support/math/expf16.h
+++ b/libc/src/__support/math/expf16.h
@@ -12,24 +12,24 @@
#include "exp_float16_constants.h"
#include "hdr/errno_macros.h"
-#include "src/math/generic/expxf16.h"
#include "hdr/fenv_macros.h"
-#include "src/__support/common.h"
#include "src/__support/FPUtil/FEnvImpl.h"
#include "src/__support/FPUtil/FPBits.h"
#include "src/__support/FPUtil/PolyEval.h"
#include "src/__support/FPUtil/cast.h"
+#include "src/__support/FPUtil/except_value_utils.h"
#include "src/__support/FPUtil/rounding_mode.h"
-#include "src/__support/macros/optimization.h"
+#include "src/__support/common.h"
#include "src/__support/macros/config.h"
-#include "src/__support/FPUtil/except_value_utils.h"
+#include "src/__support/macros/optimization.h"
+#include "src/math/generic/expxf16.h"
namespace LIBC_NAMESPACE_DECL {
namespace math {
static constexpr float16 expf16(float16 x) {
- using FPBits = fputil::FPBits<float16>;
+ using FPBits = fputil::FPBits<float16>;
FPBits x_bits(x);
uint16_t x_u = x_bits.uintval();
>From d48dbb5aeeb43ab36ffbc8a0ae22a4a3d8b7f933 Mon Sep 17 00:00:00 2001
From: bassiounix <muhammad.m.bassiouni at gmail.com>
Date: Tue, 8 Jul 2025 05:00:58 +0300
Subject: [PATCH 3/5] fix dependency
---
libc/src/math/generic/CMakeLists.txt | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/libc/src/math/generic/CMakeLists.txt b/libc/src/math/generic/CMakeLists.txt
index 8d15c2879a8bf..884d29c90fe72 100644
--- a/libc/src/math/generic/CMakeLists.txt
+++ b/libc/src/math/generic/CMakeLists.txt
@@ -1332,7 +1332,7 @@ add_entrypoint_object(
HDRS
../expf16.h
DEPENDS
- libc.src.__support.math.expf
+ libc.src.__support.math.expf16
)
add_entrypoint_object(
>From 8437b69e453db2facd0f850cf2bc678df4596952 Mon Sep 17 00:00:00 2001
From: bassiounix <muhammad.m.bassiouni at gmail.com>
Date: Tue, 8 Jul 2025 19:09:42 +0300
Subject: [PATCH 4/5] Remove `expf16_constants.h`
---
libc/src/__support/math/CMakeLists.txt | 8 ----
.../__support/math/exp_float16_constants.h | 38 -------------------
libc/src/__support/math/expf16.h | 24 ++++++++++--
.../llvm-project-overlay/libc/BUILD.bazel | 8 ----
4 files changed, 21 insertions(+), 57 deletions(-)
delete mode 100644 libc/src/__support/math/exp_float16_constants.h
diff --git a/libc/src/__support/math/CMakeLists.txt b/libc/src/__support/math/CMakeLists.txt
index 6d4d548f2e48f..a26782b6867c7 100644
--- a/libc/src/__support/math/CMakeLists.txt
+++ b/libc/src/__support/math/CMakeLists.txt
@@ -23,14 +23,6 @@ add_header_library(
libc.src.__support.macros.optimization
)
-add_header_library(
- exp_float16_constants
- HDRS
- exp_float16_constants.h
- DEPENDS
- libc.src.__support.FPUtil.except_value_utils
-)
-
add_header_library(
expf16
HDRS
diff --git a/libc/src/__support/math/exp_float16_constants.h b/libc/src/__support/math/exp_float16_constants.h
deleted file mode 100644
index 9c3aa05e9551c..0000000000000
--- a/libc/src/__support/math/exp_float16_constants.h
+++ /dev/null
@@ -1,38 +0,0 @@
-//===-- High and Low Excepts for expf16 functions ---------------*- 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_EXP_FLOAT16_CONSTANTS_H
-#define LLVM_LIBC_SRC___SUPPORT_MATH_EXP_FLOAT16_CONSTANTS_H
-
-#include "src/__support/FPUtil/except_value_utils.h"
-
-namespace LIBC_NAMESPACE_DECL {
-
-#ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
-static constexpr fputil::ExceptValues<float16, 2> EXPF16_EXCEPTS_LO = {{
- // (input, RZ output, RU offset, RD offset, RN offset)
- // x = 0x1.de4p-8, expf16(x) = 0x1.01cp+0 (RZ)
- {0x1f79U, 0x3c07U, 1U, 0U, 0U},
- // x = 0x1.73cp-6, expf16(x) = 0x1.05cp+0 (RZ)
- {0x25cfU, 0x3c17U, 1U, 0U, 0U},
-}};
-
-static constexpr fputil::ExceptValues<float16, 3> EXPF16_EXCEPTS_HI = {{
- // (input, RZ output, RU offset, RD offset, RN offset)
- // x = 0x1.c34p+0, expf16(x) = 0x1.74cp+2 (RZ)
- {0x3f0dU, 0x45d3U, 1U, 0U, 1U},
- // x = -0x1.488p-5, expf16(x) = 0x1.ebcp-1 (RZ)
- {0xa922U, 0x3bafU, 1U, 0U, 0U},
- // x = -0x1.55p-5, expf16(x) = 0x1.ebp-1 (RZ)
- {0xa954U, 0x3bacU, 1U, 0U, 0U},
-}};
-#endif // !LIBC_MATH_HAS_SKIP_ACCURATE_PASS
-
-} // namespace LIBC_NAMESPACE_DECL
-
-#endif // LLVM_LIBC_SRC___SUPPORT_MATH_EXP_FLOAT16_CONSTANTS_H
diff --git a/libc/src/__support/math/expf16.h b/libc/src/__support/math/expf16.h
index 7fd8ce0173f59..37ada30e1ae0a 100644
--- a/libc/src/__support/math/expf16.h
+++ b/libc/src/__support/math/expf16.h
@@ -9,8 +9,6 @@
#ifndef LLVM_LIBC_SRC___SUPPORT_MATH_EXPF16_H
#define LLVM_LIBC_SRC___SUPPORT_MATH_EXPF16_H
-#include "exp_float16_constants.h"
-
#include "hdr/errno_macros.h"
#include "hdr/fenv_macros.h"
#include "src/__support/FPUtil/FEnvImpl.h"
@@ -28,7 +26,27 @@ namespace LIBC_NAMESPACE_DECL {
namespace math {
-static constexpr float16 expf16(float16 x) {
+LIBC_INLINE static constexpr float16 expf16(float16 x) {
+#ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
+ constexpr fputil::ExceptValues<float16, 2> EXPF16_EXCEPTS_LO = {{
+ // (input, RZ output, RU offset, RD offset, RN offset)
+ // x = 0x1.de4p-8, expf16(x) = 0x1.01cp+0 (RZ)
+ {0x1f79U, 0x3c07U, 1U, 0U, 0U},
+ // x = 0x1.73cp-6, expf16(x) = 0x1.05cp+0 (RZ)
+ {0x25cfU, 0x3c17U, 1U, 0U, 0U},
+ }};
+
+ constexpr fputil::ExceptValues<float16, 3> EXPF16_EXCEPTS_HI = {{
+ // (input, RZ output, RU offset, RD offset, RN offset)
+ // x = 0x1.c34p+0, expf16(x) = 0x1.74cp+2 (RZ)
+ {0x3f0dU, 0x45d3U, 1U, 0U, 1U},
+ // x = -0x1.488p-5, expf16(x) = 0x1.ebcp-1 (RZ)
+ {0xa922U, 0x3bafU, 1U, 0U, 0U},
+ // x = -0x1.55p-5, expf16(x) = 0x1.ebp-1 (RZ)
+ {0xa954U, 0x3bacU, 1U, 0U, 0U},
+ }};
+#endif // !LIBC_MATH_HAS_SKIP_ACCURATE_PASS
+
using FPBits = fputil::FPBits<float16>;
FPBits x_bits(x);
diff --git a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
index efba1eb640eb8..01fa6107ebf07 100644
--- a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
@@ -2096,14 +2096,6 @@ libc_support_library(
],
)
-libc_support_library(
- name = "__support_math_exp_float16_constants",
- hdrs = ["src/__support/math/exp_float16_constants.h"],
- deps = [
- ":__support_FPUtil_except_value_utils"
- ],
-)
-
libc_support_library(
name = "__support_math_expf16",
hdrs = ["src/__support/math/expf16.h"],
>From 87159aec4eee2587d583abc5421afbb935a00346 Mon Sep 17 00:00:00 2001
From: bassiounix <muhammad.m.bassiouni at gmail.com>
Date: Tue, 8 Jul 2025 19:19:49 +0300
Subject: [PATCH 5/5] remove `LIBC_INLINE`
---
libc/src/__support/math/expf16.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/libc/src/__support/math/expf16.h b/libc/src/__support/math/expf16.h
index 37ada30e1ae0a..6df5f6bb790e9 100644
--- a/libc/src/__support/math/expf16.h
+++ b/libc/src/__support/math/expf16.h
@@ -26,7 +26,7 @@ namespace LIBC_NAMESPACE_DECL {
namespace math {
-LIBC_INLINE static constexpr float16 expf16(float16 x) {
+static constexpr float16 expf16(float16 x) {
#ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
constexpr fputil::ExceptValues<float16, 2> EXPF16_EXCEPTS_LO = {{
// (input, RZ output, RU offset, RD offset, RN offset)
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