[libc-commits] [libc] [libc][math][c23] Add acoshf16 C23 math function. (PR #130588)
Harrison Hao via libc-commits
libc-commits at lists.llvm.org
Thu Mar 13 05:52:17 PDT 2025
https://github.com/harrisonGPU updated https://github.com/llvm/llvm-project/pull/130588
>From 170d23e151ad5c07fb282d988ab8d467c2c4952f Mon Sep 17 00:00:00 2001
From: Harrison Hao <tsworld1314 at gmail.com>
Date: Mon, 10 Mar 2025 20:04:11 +0800
Subject: [PATCH 1/8] [libc][math][c23] Add acoshf16 C23 math function.
---
libc/config/linux/x86_64/entrypoints.txt | 1 +
libc/docs/headers/math/index.rst | 2 +-
libc/include/math.yaml | 7 +++
libc/src/math/CMakeLists.txt | 1 +
libc/src/math/acoshf16.h | 21 +++++++++
libc/src/math/generic/CMakeLists.txt | 20 ++++++++
libc/src/math/generic/acoshf16.cpp | 55 ++++++++++++++++++++++
libc/test/src/math/CMakeLists.txt | 11 +++++
libc/test/src/math/acoshf16_test.cpp | 52 ++++++++++++++++++++
libc/test/src/math/smoke/CMakeLists.txt | 11 +++++
libc/test/src/math/smoke/acoshf16_test.cpp | 41 ++++++++++++++++
11 files changed, 221 insertions(+), 1 deletion(-)
create mode 100644 libc/src/math/acoshf16.h
create mode 100644 libc/src/math/generic/acoshf16.cpp
create mode 100644 libc/test/src/math/acoshf16_test.cpp
create mode 100644 libc/test/src/math/smoke/acoshf16_test.cpp
diff --git a/libc/config/linux/x86_64/entrypoints.txt b/libc/config/linux/x86_64/entrypoints.txt
index 12dc87bf945fd..b705d81fff79c 100644
--- a/libc/config/linux/x86_64/entrypoints.txt
+++ b/libc/config/linux/x86_64/entrypoints.txt
@@ -653,6 +653,7 @@ if(LIBC_TYPES_HAS_FLOAT16)
# math.h C23 _Float16 entrypoints
libc.src.math.asinf16
libc.src.math.acosf16
+ libc.src.math.acoshf16
libc.src.math.canonicalizef16
libc.src.math.ceilf16
libc.src.math.copysignf16
diff --git a/libc/docs/headers/math/index.rst b/libc/docs/headers/math/index.rst
index 5b855ce4881c3..e137626361f48 100644
--- a/libc/docs/headers/math/index.rst
+++ b/libc/docs/headers/math/index.rst
@@ -251,7 +251,7 @@ Higher Math Functions
+===========+==================+=================+========================+======================+========================+========================+============================+
| acos | |check| | | | |check| | | 7.12.4.1 | F.10.1.1 |
+-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
-| acosh | |check| | | | | | 7.12.5.1 | F.10.2.1 |
+| acosh | |check| | | | |check| | | 7.12.5.1 | F.10.2.1 |
+-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
| acospi | | | | | | 7.12.4.8 | F.10.1.8 |
+-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
diff --git a/libc/include/math.yaml b/libc/include/math.yaml
index a66f981030864..7fd73445cc74e 100644
--- a/libc/include/math.yaml
+++ b/libc/include/math.yaml
@@ -27,6 +27,13 @@ functions:
return_type: float
arguments:
- type: float
+ name: acoshf16
+ standards:
+ - stdc
+ return_type: _Float16
+ arguments:
+ - type: _Float16
+ guard: LIBC_TYPES_HAS_FLOAT16
- name: asin
standards:
- stdc
diff --git a/libc/src/math/CMakeLists.txt b/libc/src/math/CMakeLists.txt
index f18a73d46f9aa..bdf8b923416d8 100644
--- a/libc/src/math/CMakeLists.txt
+++ b/libc/src/math/CMakeLists.txt
@@ -46,6 +46,7 @@ add_math_entrypoint_object(acosf16)
add_math_entrypoint_object(acosh)
add_math_entrypoint_object(acoshf)
+add_math_entrypoint_object(acoshf16)
add_math_entrypoint_object(asin)
add_math_entrypoint_object(asinf)
diff --git a/libc/src/math/acoshf16.h b/libc/src/math/acoshf16.h
new file mode 100644
index 0000000000000..a23426ffe589d
--- /dev/null
+++ b/libc/src/math/acoshf16.h
@@ -0,0 +1,21 @@
+//===-- Implementation header for acoshf16 -----------------------*- 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_MATH_ACOSHF16_H
+#define LLVM_LIBC_SRC_MATH_ACOSHF16_H
+
+#include "src/__support/macros/config.h"
+#include "src/__support/macros/properties/types.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+float16 acoshf16(float16 x);
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_MATH_ACOSHF16_H
diff --git a/libc/src/math/generic/CMakeLists.txt b/libc/src/math/generic/CMakeLists.txt
index 3114289bad486..be3634dfebdc7 100644
--- a/libc/src/math/generic/CMakeLists.txt
+++ b/libc/src/math/generic/CMakeLists.txt
@@ -3944,6 +3944,26 @@ add_entrypoint_object(
libc.src.__support.macros.optimization
)
+add_entrypoint_object(
+ acoshf16
+ SRCS
+ acoshf16.cpp
+ HDRS
+ ../acoshf16.h
+ DEPENDS
+ libc.hdr.errno_macros
+ libc.hdr.fenv_macros
+ 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.polyeval
+ libc.src.__support.FPUtil.sqrt
+ libc.src.__support.macros.optimization
+ libc.src.__support.macros.properties.types
+)
+
add_entrypoint_object(
asinhf
SRCS
diff --git a/libc/src/math/generic/acoshf16.cpp b/libc/src/math/generic/acoshf16.cpp
new file mode 100644
index 0000000000000..01f97f536c256
--- /dev/null
+++ b/libc/src/math/generic/acoshf16.cpp
@@ -0,0 +1,55 @@
+//===-- Half-precision acoshf16 function -----------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/math/acoshf16.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/sqrt.h"
+#include "src/__support/FPUtil/multiply_add.h"
+#include "src/__support/FPUtil/cast.h"
+#include "src/__support/macros/optimization.h"
+#include "src/math/generic/explogxf.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
+ using FPBits = fputil::FPBits<float16>;
+ FPBits xbits(x);
+
+ uint16_t x_u = xbits.uintval();
+ uint16_t x_abs = x_u & 0x7fff;
+
+ // acoshf16(x) domain: x >= 1.0
+ if (LIBC_UNLIKELY(x_abs < 0x3c00)) {
+ fputil::set_errno_if_required(EDOM);
+ fputil::raise_except_if_required(FE_INVALID);
+ return FPBits::quiet_nan().get_val();
+ }
+
+ if (LIBC_UNLIKELY(x == float16(1.0f)))
+ return float16(0.0f);
+
+ // acosh(inf) = inf, acosh(NaN) = NaN
+ if (LIBC_UNLIKELY(xbits.is_inf_or_nan()))
+ return x;
+
+ // Compute in float32 for accuracy
+ float xf32 = static_cast<float>(x);
+ // sqrt(x^2 - 1)
+ float sqrt_term = fputil::sqrt<float>(
+ fputil::multiply_add(xf32, xf32, -1.0f));
+
+ // log(x + sqrt(x^2 - 1))
+ float result = static_cast<float>(log_eval(xf32 + sqrt_term));
+
+ return fputil::cast<float16>(result);
+}
+
+} // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/test/src/math/CMakeLists.txt b/libc/test/src/math/CMakeLists.txt
index 53ddd301900c0..311d56a2a33ab 100644
--- a/libc/test/src/math/CMakeLists.txt
+++ b/libc/test/src/math/CMakeLists.txt
@@ -2173,6 +2173,17 @@ add_fp_unittest(
libc.src.__support.FPUtil.fp_bits
)
+add_fp_unittest(
+ acoshf16_test
+ NEED_MPFR
+ SUITE
+ libc-math-unittests
+ SRCS
+ acoshf16_test.cpp
+ DEPENDS
+ libc.src.math.acoshf16
+)
+
add_fp_unittest(
asinf_test
NEED_MPFR
diff --git a/libc/test/src/math/acoshf16_test.cpp b/libc/test/src/math/acoshf16_test.cpp
new file mode 100644
index 0000000000000..d4ebef87f3b61
--- /dev/null
+++ b/libc/test/src/math/acoshf16_test.cpp
@@ -0,0 +1,52 @@
+//===-- Unittests for acoshf16 ---------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/__support/FPUtil/FPBits.h"
+#include "src/errno/libc_errno.h"
+#include "src/math/acoshf16.h"
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+#include "utils/MPFRWrapper/MPFRUtils.h"
+
+using LlvmLibcAcoshf16Test = LIBC_NAMESPACE::testing::FPTest<float16>;
+namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
+
+TEST_F(LlvmLibcAcoshf16Test, SpecialNumbers) {
+ LIBC_NAMESPACE::libc_errno = 0;
+
+ // NaN input
+ EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::acoshf16(aNaN));
+ EXPECT_MATH_ERRNO(0);
+
+ // acoshf16(1.0) = 0
+ EXPECT_FP_EQ_ALL_ROUNDING(float16(0.0f), LIBC_NAMESPACE::acoshf16(float16(1.0f)));
+ EXPECT_MATH_ERRNO(0);
+
+ // Domain error (x < 1)
+ EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::acoshf16(float16(0.5f)));
+ EXPECT_MATH_ERRNO(EDOM);
+
+ // acoshf16(+inf) = inf
+ EXPECT_FP_EQ_ALL_ROUNDING(inf, LIBC_NAMESPACE::acoshf16(inf));
+ EXPECT_MATH_ERRNO(0);
+
+ // acoshf16(x) domain error (negative infinity)
+ EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::acoshf16(neg_inf));
+ EXPECT_MATH_ERRNO(EDOM);
+}
+
+TEST_F(LlvmLibcAcoshf16Test, InFloat16Range) {
+ constexpr uint16_t START = 0x3c00U; // 1.0
+ constexpr uint16_t STOP = 0x7bffU; // Largest finite float16 value
+
+ for (uint16_t bits = START; bits <= STOP; ++bits) {
+ float16 x = FPBits(bits).get_val();
+ ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Acosh, float(x),
+ float(LIBC_NAMESPACE::acoshf16(x)), 0.5);
+ }
+}
diff --git a/libc/test/src/math/smoke/CMakeLists.txt b/libc/test/src/math/smoke/CMakeLists.txt
index 6f94440d826d9..4303afd242e22 100644
--- a/libc/test/src/math/smoke/CMakeLists.txt
+++ b/libc/test/src/math/smoke/CMakeLists.txt
@@ -3945,6 +3945,17 @@ add_fp_unittest(
libc.src.__support.FPUtil.fp_bits
)
+add_fp_unittest(
+ acoshf16_test
+ SUITE
+ libc-math-smoke-tests
+ SRCS
+ acoshf16_test.cpp
+ DEPENDS
+ libc.src.errno.errno
+ libc.src.math.acoshf16
+)
+
add_fp_unittest(
asinf_test
SUITE
diff --git a/libc/test/src/math/smoke/acoshf16_test.cpp b/libc/test/src/math/smoke/acoshf16_test.cpp
new file mode 100644
index 0000000000000..e197f3f305834
--- /dev/null
+++ b/libc/test/src/math/smoke/acoshf16_test.cpp
@@ -0,0 +1,41 @@
+//===-- Unittests for acoshf16 --------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/errno/libc_errno.h"
+#include "src/math/acoshf16.h"
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+
+using LlvmLibcAcoshf16Test = LIBC_NAMESPACE::testing::FPTest<float16>;
+
+TEST_F(LlvmLibcAcoshf16Test, SpecialNumbers) {
+ LIBC_NAMESPACE::libc_errno = 0;
+ EXPECT_FP_EQ(aNaN, LIBC_NAMESPACE::acoshf16(aNaN));
+ EXPECT_MATH_ERRNO(0);
+
+ EXPECT_FP_EQ_WITH_EXCEPTION(aNaN, LIBC_NAMESPACE::acoshf16(sNaN), FE_INVALID);
+ EXPECT_MATH_ERRNO(0);
+
+ EXPECT_FP_EQ(aNaN, LIBC_NAMESPACE::acoshf16(zero));
+ EXPECT_MATH_ERRNO(EDOM);
+
+ EXPECT_FP_EQ(aNaN, LIBC_NAMESPACE::acoshf16(neg_zero));
+ EXPECT_MATH_ERRNO(EDOM);
+
+ EXPECT_FP_EQ(inf, LIBC_NAMESPACE::acoshf16(inf));
+ EXPECT_MATH_ERRNO(0);
+
+ EXPECT_FP_EQ(aNaN, LIBC_NAMESPACE::acoshf16(neg_inf));
+ EXPECT_MATH_ERRNO(EDOM);
+
+ EXPECT_FP_EQ(float16(0.0f), LIBC_NAMESPACE::acoshf16(float16(1.0f)));
+ EXPECT_MATH_ERRNO(0);
+
+ EXPECT_FP_EQ(aNaN, LIBC_NAMESPACE::acoshf16(float16(0.5f)));
+ EXPECT_MATH_ERRNO(EDOM);
+}
\ No newline at end of file
>From 18e165b6114096c1ce3f4ffc576ad95e944d947f Mon Sep 17 00:00:00 2001
From: Harrison Hao <tsworld1314 at gmail.com>
Date: Mon, 10 Mar 2025 21:57:22 +0800
Subject: [PATCH 2/8] [libc][math][c23] Fix some build issues.
---
libc/src/math/generic/CMakeLists.txt | 2 +
libc/src/math/generic/acoshf16.cpp | 58 +++++++++++++++++++++-------
libc/test/src/math/acoshf16_test.cpp | 51 +++++++++++++++++-------
3 files changed, 83 insertions(+), 28 deletions(-)
diff --git a/libc/src/math/generic/CMakeLists.txt b/libc/src/math/generic/CMakeLists.txt
index be3634dfebdc7..db5a23c199eea 100644
--- a/libc/src/math/generic/CMakeLists.txt
+++ b/libc/src/math/generic/CMakeLists.txt
@@ -3951,6 +3951,8 @@ add_entrypoint_object(
HDRS
../acoshf16.h
DEPENDS
+ .common_constants
+ .explogxf
libc.hdr.errno_macros
libc.hdr.fenv_macros
libc.src.__support.FPUtil.cast
diff --git a/libc/src/math/generic/acoshf16.cpp b/libc/src/math/generic/acoshf16.cpp
index 01f97f536c256..dc8bdebc90abb 100644
--- a/libc/src/math/generic/acoshf16.cpp
+++ b/libc/src/math/generic/acoshf16.cpp
@@ -11,10 +11,11 @@
#include "hdr/fenv_macros.h"
#include "src/__support/FPUtil/FEnvImpl.h"
#include "src/__support/FPUtil/FPBits.h"
-#include "src/__support/FPUtil/sqrt.h"
-#include "src/__support/FPUtil/multiply_add.h"
#include "src/__support/FPUtil/cast.h"
+#include "src/__support/FPUtil/multiply_add.h"
+#include "src/__support/FPUtil/sqrt.h"
#include "src/__support/macros/optimization.h"
+#include "src/math/generic/common_constants.h"
#include "src/math/generic/explogxf.h"
namespace LIBC_NAMESPACE_DECL {
@@ -26,30 +27,57 @@ LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
uint16_t x_u = xbits.uintval();
uint16_t x_abs = x_u & 0x7fff;
- // acoshf16(x) domain: x >= 1.0
+ // Check for NaN input first.
+ if (LIBC_UNLIKELY(xbits.is_nan())) {
+ if (xbits.is_signaling_nan()) {
+ fputil::raise_except(FE_INVALID);
+ return FPBits::quiet_nan().get_val();
+ }
+ return x;
+ }
+
+ // Check for infinite inputs.
+ if (LIBC_UNLIKELY(xbits.is_inf())) {
+ if (xbits.is_neg()) {
+ fputil::set_errno_if_required(EDOM);
+ fputil::raise_except(FE_INVALID);
+ return FPBits::quiet_nan().get_val();
+ }
+ return x;
+ }
+
+ // Domain error for inputs less than 1.0.
if (LIBC_UNLIKELY(x_abs < 0x3c00)) {
fputil::set_errno_if_required(EDOM);
- fputil::raise_except_if_required(FE_INVALID);
+ fputil::raise_except(FE_INVALID);
return FPBits::quiet_nan().get_val();
}
- if (LIBC_UNLIKELY(x == float16(1.0f)))
+ // acosh(1.0) exactly equals 0.0
+ if (LIBC_UNLIKELY(xbits.uintval() == 0x3c00U))
return float16(0.0f);
- // acosh(inf) = inf, acosh(NaN) = NaN
- if (LIBC_UNLIKELY(xbits.is_inf_or_nan()))
- return x;
-
- // Compute in float32 for accuracy
float xf32 = static_cast<float>(x);
- // sqrt(x^2 - 1)
- float sqrt_term = fputil::sqrt<float>(
- fputil::multiply_add(xf32, xf32, -1.0f));
- // log(x + sqrt(x^2 - 1))
+ // High precision for inputs very close to 1.0
+ if (LIBC_UNLIKELY(xf32 < 1.25f)) {
+ float delta = xf32 - 1.0f;
+ float sqrt_2_delta = fputil::sqrt<float>(2.0f * delta);
+ double correction = (double)delta / 12.0 - (3.0 * (double)delta * delta) / 160.0;
+ double precise_result = (double)sqrt_2_delta * (1.0 - correction);
+ return fputil::cast<float16>(static_cast<float>(precise_result));
+ }
+ // Special optimization for large input values.
+ if (LIBC_UNLIKELY(xf32 >= 32.0f)) {
+ float result = static_cast<float>(log_eval(2.0f * xf32));
+ return fputil::cast<float16>(result);
+ }
+
+ // Standard computation for general case.
+ float sqrt_term = fputil::sqrt<float>(fputil::multiply_add(xf32, xf32, -1.0f));
float result = static_cast<float>(log_eval(xf32 + sqrt_term));
return fputil::cast<float16>(result);
}
-} // namespace LIBC_NAMESPACE_DECL
+} // namespace LIBC_NAMESPACE_DECL
\ No newline at end of file
diff --git a/libc/test/src/math/acoshf16_test.cpp b/libc/test/src/math/acoshf16_test.cpp
index d4ebef87f3b61..099486ba338c0 100644
--- a/libc/test/src/math/acoshf16_test.cpp
+++ b/libc/test/src/math/acoshf16_test.cpp
@@ -1,17 +1,17 @@
-//===-- Unittests for acoshf16 ---------------------------------------------===//
+//===-- Unittests for acoshf16 ----------------------------------------------===//
//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// 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
//
//===----------------------------------------------------------------------===//
-#include "src/__support/FPUtil/FPBits.h"
#include "src/errno/libc_errno.h"
#include "src/math/acoshf16.h"
+#include "src/__support/FPUtil/FPBits.h"
#include "test/UnitTest/FPMatcher.h"
-#include "test/UnitTest/Test.h"
#include "utils/MPFRWrapper/MPFRUtils.h"
+#include <stdint.h>
using LlvmLibcAcoshf16Test = LIBC_NAMESPACE::testing::FPTest<float16>;
namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
@@ -19,34 +19,59 @@ namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
TEST_F(LlvmLibcAcoshf16Test, SpecialNumbers) {
LIBC_NAMESPACE::libc_errno = 0;
- // NaN input
EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::acoshf16(aNaN));
EXPECT_MATH_ERRNO(0);
- // acoshf16(1.0) = 0
- EXPECT_FP_EQ_ALL_ROUNDING(float16(0.0f), LIBC_NAMESPACE::acoshf16(float16(1.0f)));
+ EXPECT_FP_EQ_WITH_EXCEPTION(aNaN, LIBC_NAMESPACE::acoshf16(sNaN), FE_INVALID);
+ EXPECT_MATH_ERRNO(0);
+
+ EXPECT_FP_EQ_ALL_ROUNDING(float16(0.0f),
+ LIBC_NAMESPACE::acoshf16(float16(1.0f)));
EXPECT_MATH_ERRNO(0);
- // Domain error (x < 1)
EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::acoshf16(float16(0.5f)));
EXPECT_MATH_ERRNO(EDOM);
- // acoshf16(+inf) = inf
EXPECT_FP_EQ_ALL_ROUNDING(inf, LIBC_NAMESPACE::acoshf16(inf));
EXPECT_MATH_ERRNO(0);
- // acoshf16(x) domain error (negative infinity)
EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::acoshf16(neg_inf));
EXPECT_MATH_ERRNO(EDOM);
}
TEST_F(LlvmLibcAcoshf16Test, InFloat16Range) {
- constexpr uint16_t START = 0x3c00U; // 1.0
- constexpr uint16_t STOP = 0x7bffU; // Largest finite float16 value
+ constexpr uint16_t START = 0x3C00U; // 1.0
+ constexpr uint16_t STOP = 0x7BFFU; // Largest finite float16 value
for (uint16_t bits = START; bits <= STOP; ++bits) {
float16 x = FPBits(bits).get_val();
+ if (FPBits(bits).is_nan() || FPBits(bits).is_inf())
+ continue;
ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Acosh, float(x),
- float(LIBC_NAMESPACE::acoshf16(x)), 0.5);
+ float(LIBC_NAMESPACE::acoshf16(x)),
+ 5.0);
+ }
+}
+
+TEST_F(LlvmLibcAcoshf16Test, SpecificBitPatterns) {
+ constexpr int N = 12;
+ constexpr uint16_t INPUTS[N] = {
+ 0x3C00, // 1.0
+ 0x3C01, // just above 1.0 (minimally larger than 1)
+ 0x3E00, // 1.5
+ 0x4200, // 3.0
+ 0x4500, // 5.0
+ 0x4900, // 10.0
+ 0x51FF, // ~47.94 (random mid-range value)
+ 0x5CB0, // ~300.0 (random mid-range value)
+ 0x643F, // ~1087.6 (random large value)
+ 0x77FF, // just below next exponent interval (max for exponent 0x1D)
+ 0x7801, // just above previous value (min for exponent 0x1E)
+ 0x7BFF // 65504.0 (max finite half)
+ };
+ for (int i = 0; i < N; ++i) {
+ float16 x = FPBits(INPUTS[i]).get_val();
+ EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Acosh, x,
+ LIBC_NAMESPACE::acoshf16(x), 0.5);
}
}
>From 7711a3ba00f402939306c63c604967bd48b1d0a5 Mon Sep 17 00:00:00 2001
From: Harrison Hao <tsworld1314 at gmail.com>
Date: Tue, 11 Mar 2025 11:13:10 +0800
Subject: [PATCH 3/8] [libc][math][c23] Fix some test failures.
---
libc/src/math/generic/acoshf16.cpp | 25 ++++++++++++----
libc/test/src/math/acoshf16_test.cpp | 45 +++++++++++++++-------------
2 files changed, 45 insertions(+), 25 deletions(-)
diff --git a/libc/src/math/generic/acoshf16.cpp b/libc/src/math/generic/acoshf16.cpp
index dc8bdebc90abb..8d629bad55c92 100644
--- a/libc/src/math/generic/acoshf16.cpp
+++ b/libc/src/math/generic/acoshf16.cpp
@@ -23,10 +23,18 @@ namespace LIBC_NAMESPACE_DECL {
LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
using FPBits = fputil::FPBits<float16>;
FPBits xbits(x);
-
uint16_t x_u = xbits.uintval();
uint16_t x_abs = x_u & 0x7fff;
+// if (LIBC_UNLIKELY(x <= 1.0f)) {
+// if (x == 1.0f)
+// return 0.0f;
+// // x < 1.
+// fputil::set_errno_if_required(EDOM);
+// fputil::raise_except_if_required(FE_INVALID);
+// return FPBits::quiet_nan().get_val();
+// }
+
// Check for NaN input first.
if (LIBC_UNLIKELY(xbits.is_nan())) {
if (xbits.is_signaling_nan()) {
@@ -62,11 +70,18 @@ LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
// High precision for inputs very close to 1.0
if (LIBC_UNLIKELY(xf32 < 1.25f)) {
float delta = xf32 - 1.0f;
- float sqrt_2_delta = fputil::sqrt<float>(2.0f * delta);
- double correction = (double)delta / 12.0 - (3.0 * (double)delta * delta) / 160.0;
- double precise_result = (double)sqrt_2_delta * (1.0 - correction);
- return fputil::cast<float16>(static_cast<float>(precise_result));
+ float sqrt_2 = fputil::sqrt<float>(2.0f * delta);
+ float sqrt_2d = fputil::sqrt<float>(2.0f * delta);
+ float d32 = delta * fputil::sqrt<float>(delta);
+ float term2 = d32 / (6.0f * fputil::sqrt<float>(2.0f));
+ float d52 = d32 * delta;
+ float term3 = 3.0f * d52 / (80.0f * sqrt_2);
+ float d72 = d52 * delta;
+ float term4 = 5.0f * d72 / (1792.0f * sqrt_2);
+ float result = sqrt_2d - term2 + term3 - term4;
+ return fputil::cast<float16>(result);
}
+
// Special optimization for large input values.
if (LIBC_UNLIKELY(xf32 >= 32.0f)) {
float result = static_cast<float>(log_eval(2.0f * xf32));
diff --git a/libc/test/src/math/acoshf16_test.cpp b/libc/test/src/math/acoshf16_test.cpp
index 099486ba338c0..d13e8f693f80b 100644
--- a/libc/test/src/math/acoshf16_test.cpp
+++ b/libc/test/src/math/acoshf16_test.cpp
@@ -6,6 +6,7 @@
//
//===----------------------------------------------------------------------===//
+#include "src/__support/FPUtil/cast.h"
#include "src/errno/libc_errno.h"
#include "src/math/acoshf16.h"
#include "src/__support/FPUtil/FPBits.h"
@@ -40,34 +41,38 @@ TEST_F(LlvmLibcAcoshf16Test, SpecialNumbers) {
}
TEST_F(LlvmLibcAcoshf16Test, InFloat16Range) {
- constexpr uint16_t START = 0x3C00U; // 1.0
- constexpr uint16_t STOP = 0x7BFFU; // Largest finite float16 value
+ constexpr uint32_t COUNT = 100'000;
+ constexpr uint32_t STEP = UINT32_MAX / COUNT;
- for (uint16_t bits = START; bits <= STOP; ++bits) {
- float16 x = FPBits(bits).get_val();
- if (FPBits(bits).is_nan() || FPBits(bits).is_inf())
+ for (uint32_t i = 0, v = 0; i <= COUNT; ++i, v += STEP) {
+ LIBC_NAMESPACE::fputil::FPBits<float> bits(v);
+ float xf32 = bits.get_val();
+ if (bits.is_nan() || bits.is_inf())
continue;
- ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Acosh, float(x),
- float(LIBC_NAMESPACE::acoshf16(x)),
- 5.0);
+ if (xf32 < 1.0f)
+ continue;
+ float16 xh = LIBC_NAMESPACE::fputil::cast<float16>(xf32);
+
+ EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Acosh, xh,
+ LIBC_NAMESPACE::acoshf16(xh), 3.0);
}
}
TEST_F(LlvmLibcAcoshf16Test, SpecificBitPatterns) {
constexpr int N = 12;
constexpr uint16_t INPUTS[N] = {
- 0x3C00, // 1.0
- 0x3C01, // just above 1.0 (minimally larger than 1)
- 0x3E00, // 1.5
- 0x4200, // 3.0
- 0x4500, // 5.0
- 0x4900, // 10.0
- 0x51FF, // ~47.94 (random mid-range value)
- 0x5CB0, // ~300.0 (random mid-range value)
- 0x643F, // ~1087.6 (random large value)
- 0x77FF, // just below next exponent interval (max for exponent 0x1D)
- 0x7801, // just above previous value (min for exponent 0x1E)
- 0x7BFF // 65504.0 (max finite half)
+ 0x3C00, // x = 1.0
+ 0x3C01, // x = just above 1.0 (minimally larger than 1)
+ 0x3E00, // x = 1.5
+ 0x4200, // x = 3.0
+ 0x4500, // x = 5.0
+ 0x4900, // x = 10.0
+ 0x51FF, // x = ~47.94
+ 0x5CB0, // x = ~300.0
+ 0x643F, // x = ~1087.6
+ 0x77FF, // x = just below next exponent interval (max for exponent 0x1D)
+ 0x7801, // x = just above previous value (min for exponent 0x1E)
+ 0x7BFF // x = 65504.0 (max finite half)
};
for (int i = 0; i < N; ++i) {
float16 x = FPBits(INPUTS[i]).get_val();
>From 2c140519f3f4f89fbc254f4300e2b319495077f3 Mon Sep 17 00:00:00 2001
From: Harrison Hao <tsworld1314 at gmail.com>
Date: Tue, 11 Mar 2025 20:19:01 +0800
Subject: [PATCH 4/8] [libc][math][c23] Do some change for comments.
---
libc/docs/headers/math/index.rst | 2 +-
libc/src/math/acoshf16.h | 2 +-
libc/src/math/generic/acoshf16.cpp | 46 ++++++++++++++--------------
libc/test/src/math/acoshf16_test.cpp | 22 +++++--------
4 files changed, 33 insertions(+), 39 deletions(-)
diff --git a/libc/docs/headers/math/index.rst b/libc/docs/headers/math/index.rst
index e137626361f48..8dc7c8c1a0966 100644
--- a/libc/docs/headers/math/index.rst
+++ b/libc/docs/headers/math/index.rst
@@ -251,7 +251,7 @@ Higher Math Functions
+===========+==================+=================+========================+======================+========================+========================+============================+
| acos | |check| | | | |check| | | 7.12.4.1 | F.10.1.1 |
+-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
-| acosh | |check| | | | |check| | | 7.12.5.1 | F.10.2.1 |
+| acosh | |check| | | | |check| | | 7.12.5.1 | F.10.2.1 |
+-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
| acospi | | | | | | 7.12.4.8 | F.10.1.8 |
+-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
diff --git a/libc/src/math/acoshf16.h b/libc/src/math/acoshf16.h
index a23426ffe589d..f471ecfeb6154 100644
--- a/libc/src/math/acoshf16.h
+++ b/libc/src/math/acoshf16.h
@@ -1,4 +1,4 @@
-//===-- Implementation header for acoshf16 -----------------------*- C++ -*-===//
+//===-- Implementation header for acoshf16 ----------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
diff --git a/libc/src/math/generic/acoshf16.cpp b/libc/src/math/generic/acoshf16.cpp
index 8d629bad55c92..8ebaabdf670ad 100644
--- a/libc/src/math/generic/acoshf16.cpp
+++ b/libc/src/math/generic/acoshf16.cpp
@@ -1,4 +1,4 @@
-//===-- Half-precision acoshf16 function -----------------------------------===//
+//===-- Half-precision acoshf16 function ----------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
@@ -38,7 +38,7 @@ LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
// Check for NaN input first.
if (LIBC_UNLIKELY(xbits.is_nan())) {
if (xbits.is_signaling_nan()) {
- fputil::raise_except(FE_INVALID);
+ fputil::raise_except_if_required(FE_INVALID);
return FPBits::quiet_nan().get_val();
}
return x;
@@ -48,7 +48,7 @@ LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
if (LIBC_UNLIKELY(xbits.is_inf())) {
if (xbits.is_neg()) {
fputil::set_errno_if_required(EDOM);
- fputil::raise_except(FE_INVALID);
+ fputil::raise_except_if_required(FE_INVALID);
return FPBits::quiet_nan().get_val();
}
return x;
@@ -57,36 +57,36 @@ LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
// Domain error for inputs less than 1.0.
if (LIBC_UNLIKELY(x_abs < 0x3c00)) {
fputil::set_errno_if_required(EDOM);
- fputil::raise_except(FE_INVALID);
+ fputil::raise_except_if_required(FE_INVALID);
return FPBits::quiet_nan().get_val();
}
// acosh(1.0) exactly equals 0.0
- if (LIBC_UNLIKELY(xbits.uintval() == 0x3c00U))
+ if (LIBC_UNLIKELY(x_u == 0x3c00U))
return float16(0.0f);
float xf32 = static_cast<float>(x);
// High precision for inputs very close to 1.0
- if (LIBC_UNLIKELY(xf32 < 1.25f)) {
- float delta = xf32 - 1.0f;
- float sqrt_2 = fputil::sqrt<float>(2.0f * delta);
- float sqrt_2d = fputil::sqrt<float>(2.0f * delta);
- float d32 = delta * fputil::sqrt<float>(delta);
- float term2 = d32 / (6.0f * fputil::sqrt<float>(2.0f));
- float d52 = d32 * delta;
- float term3 = 3.0f * d52 / (80.0f * sqrt_2);
- float d72 = d52 * delta;
- float term4 = 5.0f * d72 / (1792.0f * sqrt_2);
- float result = sqrt_2d - term2 + term3 - term4;
- return fputil::cast<float16>(result);
- }
+ // if (LIBC_UNLIKELY(xf32 < 1.25f)) {
+ // float delta = xf32 - 1.0f;
+ // float sqrt_2 = fputil::sqrt<float>(2.0f * delta);
+ // float sqrt_2d = fputil::sqrt<float>(2.0f * delta);
+ // float d32 = delta * fputil::sqrt<float>(delta);
+ // float term2 = d32 / (6.0f * fputil::sqrt<float>(2.0f));
+ // float d52 = d32 * delta;
+ // float term3 = 3.0f * d52 / (80.0f * sqrt_2);
+ // float d72 = d52 * delta;
+ // float term4 = 5.0f * d72 / (1792.0f * sqrt_2);
+ // float result = sqrt_2d - term2 + term3 - term4;
+ // return fputil::cast<float16>(result);
+ // }
// Special optimization for large input values.
- if (LIBC_UNLIKELY(xf32 >= 32.0f)) {
- float result = static_cast<float>(log_eval(2.0f * xf32));
- return fputil::cast<float16>(result);
- }
+ // if (LIBC_UNLIKELY(xf32 >= 32.0f)) {
+ // float result = static_cast<float>(log_eval(2.0f * xf32));
+ // return fputil::cast<float16>(result);
+ // }
// Standard computation for general case.
float sqrt_term = fputil::sqrt<float>(fputil::multiply_add(xf32, xf32, -1.0f));
@@ -95,4 +95,4 @@ LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
return fputil::cast<float16>(result);
}
-} // namespace LIBC_NAMESPACE_DECL
\ No newline at end of file
+} // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/test/src/math/acoshf16_test.cpp b/libc/test/src/math/acoshf16_test.cpp
index d13e8f693f80b..2e457815debcd 100644
--- a/libc/test/src/math/acoshf16_test.cpp
+++ b/libc/test/src/math/acoshf16_test.cpp
@@ -17,6 +17,9 @@
using LlvmLibcAcoshf16Test = LIBC_NAMESPACE::testing::FPTest<float16>;
namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
+static constexpr uint16_t START = 0x3c00U;
+static constexpr uint16_t STOP = 0x7bffU;
+
TEST_F(LlvmLibcAcoshf16Test, SpecialNumbers) {
LIBC_NAMESPACE::libc_errno = 0;
@@ -40,21 +43,12 @@ TEST_F(LlvmLibcAcoshf16Test, SpecialNumbers) {
EXPECT_MATH_ERRNO(EDOM);
}
-TEST_F(LlvmLibcAcoshf16Test, InFloat16Range) {
- constexpr uint32_t COUNT = 100'000;
- constexpr uint32_t STEP = UINT32_MAX / COUNT;
-
- for (uint32_t i = 0, v = 0; i <= COUNT; ++i, v += STEP) {
- LIBC_NAMESPACE::fputil::FPBits<float> bits(v);
- float xf32 = bits.get_val();
- if (bits.is_nan() || bits.is_inf())
- continue;
- if (xf32 < 1.0f)
- continue;
- float16 xh = LIBC_NAMESPACE::fputil::cast<float16>(xf32);
+TEST_F(LlvmLibcAcoshf16Test, PositiveRange) {
+ for (uint16_t v = START; v <= STOP; ++v) {
+ float16 x = FPBits(v).get_val();
- EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Acosh, xh,
- LIBC_NAMESPACE::acoshf16(xh), 3.0);
+ EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Acosh, x,
+ LIBC_NAMESPACE::acoshf16(x), 3.0);
}
}
>From 7ddbb63f4e1be4eeb96bebdf40c630c56e3af47b Mon Sep 17 00:00:00 2001
From: Harrison Hao <tsworld1314 at gmail.com>
Date: Tue, 11 Mar 2025 20:35:32 +0800
Subject: [PATCH 5/8] [libc][math][c23] Do some change for comments again.
---
libc/src/math/generic/CMakeLists.txt | 1 -
libc/src/math/generic/acoshf16.cpp | 4 ++--
libc/test/src/math/acoshf16_test.cpp | 2 +-
libc/test/src/math/smoke/acoshf16_test.cpp | 2 +-
4 files changed, 4 insertions(+), 5 deletions(-)
diff --git a/libc/src/math/generic/CMakeLists.txt b/libc/src/math/generic/CMakeLists.txt
index db5a23c199eea..fd5ecd72b765f 100644
--- a/libc/src/math/generic/CMakeLists.txt
+++ b/libc/src/math/generic/CMakeLists.txt
@@ -3956,7 +3956,6 @@ add_entrypoint_object(
libc.hdr.errno_macros
libc.hdr.fenv_macros
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
diff --git a/libc/src/math/generic/acoshf16.cpp b/libc/src/math/generic/acoshf16.cpp
index 8ebaabdf670ad..be596873579d1 100644
--- a/libc/src/math/generic/acoshf16.cpp
+++ b/libc/src/math/generic/acoshf16.cpp
@@ -55,7 +55,7 @@ LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
}
// Domain error for inputs less than 1.0.
- if (LIBC_UNLIKELY(x_abs < 0x3c00)) {
+ if (LIBC_UNLIKELY(x_abs < 0x3c00U)) {
fputil::set_errno_if_required(EDOM);
fputil::raise_except_if_required(FE_INVALID);
return FPBits::quiet_nan().get_val();
@@ -65,7 +65,7 @@ LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
if (LIBC_UNLIKELY(x_u == 0x3c00U))
return float16(0.0f);
- float xf32 = static_cast<float>(x);
+ float xf32 = x;
// High precision for inputs very close to 1.0
// if (LIBC_UNLIKELY(xf32 < 1.25f)) {
diff --git a/libc/test/src/math/acoshf16_test.cpp b/libc/test/src/math/acoshf16_test.cpp
index 2e457815debcd..d2883abc0f350 100644
--- a/libc/test/src/math/acoshf16_test.cpp
+++ b/libc/test/src/math/acoshf16_test.cpp
@@ -1,4 +1,4 @@
-//===-- Unittests for acoshf16 ----------------------------------------------===//
+//===-- Unittests for acoshf16 --------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
diff --git a/libc/test/src/math/smoke/acoshf16_test.cpp b/libc/test/src/math/smoke/acoshf16_test.cpp
index e197f3f305834..b8d13b9fe88c3 100644
--- a/libc/test/src/math/smoke/acoshf16_test.cpp
+++ b/libc/test/src/math/smoke/acoshf16_test.cpp
@@ -38,4 +38,4 @@ TEST_F(LlvmLibcAcoshf16Test, SpecialNumbers) {
EXPECT_FP_EQ(aNaN, LIBC_NAMESPACE::acoshf16(float16(0.5f)));
EXPECT_MATH_ERRNO(EDOM);
-}
\ No newline at end of file
+}
>From 4517e2fb287dbadecd7fc8be6bdcddaa465f9b7d Mon Sep 17 00:00:00 2001
From: Harrison Hao <tsworld1314 at gmail.com>
Date: Tue, 11 Mar 2025 20:50:15 +0800
Subject: [PATCH 6/8] [libc][math][c23] Fix clang format issue.
---
libc/src/math/generic/acoshf16.cpp | 21 +++++++++++----------
libc/test/src/math/acoshf16_test.cpp | 6 +++---
2 files changed, 14 insertions(+), 13 deletions(-)
diff --git a/libc/src/math/generic/acoshf16.cpp b/libc/src/math/generic/acoshf16.cpp
index be596873579d1..162ec9cd1bbb4 100644
--- a/libc/src/math/generic/acoshf16.cpp
+++ b/libc/src/math/generic/acoshf16.cpp
@@ -26,15 +26,15 @@ LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
uint16_t x_u = xbits.uintval();
uint16_t x_abs = x_u & 0x7fff;
-// if (LIBC_UNLIKELY(x <= 1.0f)) {
-// if (x == 1.0f)
-// return 0.0f;
-// // x < 1.
-// fputil::set_errno_if_required(EDOM);
-// fputil::raise_except_if_required(FE_INVALID);
-// return FPBits::quiet_nan().get_val();
-// }
-
+ // if (LIBC_UNLIKELY(x <= 1.0f)) {
+ // if (x == 1.0f)
+ // return 0.0f;
+ // // x < 1.
+ // fputil::set_errno_if_required(EDOM);
+ // fputil::raise_except_if_required(FE_INVALID);
+ // return FPBits::quiet_nan().get_val();
+ // }
+
// Check for NaN input first.
if (LIBC_UNLIKELY(xbits.is_nan())) {
if (xbits.is_signaling_nan()) {
@@ -89,7 +89,8 @@ LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
// }
// Standard computation for general case.
- float sqrt_term = fputil::sqrt<float>(fputil::multiply_add(xf32, xf32, -1.0f));
+ float sqrt_term =
+ fputil::sqrt<float>(fputil::multiply_add(xf32, xf32, -1.0f));
float result = static_cast<float>(log_eval(xf32 + sqrt_term));
return fputil::cast<float16>(result);
diff --git a/libc/test/src/math/acoshf16_test.cpp b/libc/test/src/math/acoshf16_test.cpp
index d2883abc0f350..84574a565b9be 100644
--- a/libc/test/src/math/acoshf16_test.cpp
+++ b/libc/test/src/math/acoshf16_test.cpp
@@ -1,15 +1,15 @@
//===-- Unittests for acoshf16 --------------------------------------------===//
//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// 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
//
//===----------------------------------------------------------------------===//
+#include "src/__support/FPUtil/FPBits.h"
#include "src/__support/FPUtil/cast.h"
#include "src/errno/libc_errno.h"
#include "src/math/acoshf16.h"
-#include "src/__support/FPUtil/FPBits.h"
#include "test/UnitTest/FPMatcher.h"
#include "utils/MPFRWrapper/MPFRUtils.h"
#include <stdint.h>
@@ -18,7 +18,7 @@ using LlvmLibcAcoshf16Test = LIBC_NAMESPACE::testing::FPTest<float16>;
namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
static constexpr uint16_t START = 0x3c00U;
-static constexpr uint16_t STOP = 0x7bffU;
+static constexpr uint16_t STOP = 0x7bffU;
TEST_F(LlvmLibcAcoshf16Test, SpecialNumbers) {
LIBC_NAMESPACE::libc_errno = 0;
>From 82de264d8321866693420f64e8559476af3ac4f9 Mon Sep 17 00:00:00 2001
From: Harrison Hao <tsworld1314 at gmail.com>
Date: Wed, 12 Mar 2025 21:57:24 +0800
Subject: [PATCH 7/8] [libc][math][c23] Reduce MPFR to 1.
---
libc/src/math/generic/acoshf16.cpp | 51 +++++++++++-----------------
libc/test/src/math/acoshf16_test.cpp | 2 +-
2 files changed, 21 insertions(+), 32 deletions(-)
diff --git a/libc/src/math/generic/acoshf16.cpp b/libc/src/math/generic/acoshf16.cpp
index 162ec9cd1bbb4..c133026f8f445 100644
--- a/libc/src/math/generic/acoshf16.cpp
+++ b/libc/src/math/generic/acoshf16.cpp
@@ -7,34 +7,28 @@
//===----------------------------------------------------------------------===//
#include "src/math/acoshf16.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/cast.h"
+#include "src/__support/FPUtil/except_value_utils.h"
+#include "src/__support/FPUtil/generic/sqrt.h"
#include "src/__support/FPUtil/multiply_add.h"
-#include "src/__support/FPUtil/sqrt.h"
#include "src/__support/macros/optimization.h"
-#include "src/math/generic/common_constants.h"
#include "src/math/generic/explogxf.h"
namespace LIBC_NAMESPACE_DECL {
+static constexpr size_t N_EXCEPTS = 1;
+static constexpr fputil::ExceptValues<float16, N_EXCEPTS> ACOSHF16_EXCEPTS{
+ {// (input, RZ output, RU offset, RD offset, RN offset)
+ {0x41B7, 0x3ED8, 0, 1, 0}}};
+
LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
using FPBits = fputil::FPBits<float16>;
FPBits xbits(x);
uint16_t x_u = xbits.uintval();
uint16_t x_abs = x_u & 0x7fff;
- // if (LIBC_UNLIKELY(x <= 1.0f)) {
- // if (x == 1.0f)
- // return 0.0f;
- // // x < 1.
- // fputil::set_errno_if_required(EDOM);
- // fputil::raise_except_if_required(FE_INVALID);
- // return FPBits::quiet_nan().get_val();
- // }
-
// Check for NaN input first.
if (LIBC_UNLIKELY(xbits.is_nan())) {
if (xbits.is_signaling_nan()) {
@@ -68,25 +62,20 @@ LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
float xf32 = x;
// High precision for inputs very close to 1.0
- // if (LIBC_UNLIKELY(xf32 < 1.25f)) {
- // float delta = xf32 - 1.0f;
- // float sqrt_2 = fputil::sqrt<float>(2.0f * delta);
- // float sqrt_2d = fputil::sqrt<float>(2.0f * delta);
- // float d32 = delta * fputil::sqrt<float>(delta);
- // float term2 = d32 / (6.0f * fputil::sqrt<float>(2.0f));
- // float d52 = d32 * delta;
- // float term3 = 3.0f * d52 / (80.0f * sqrt_2);
- // float d72 = d52 * delta;
- // float term4 = 5.0f * d72 / (1792.0f * sqrt_2);
- // float result = sqrt_2d - term2 + term3 - term4;
- // return fputil::cast<float16>(result);
- // }
+ if (LIBC_UNLIKELY(xf32 < 1.25f)) {
+ float delta = xf32 - 1.0f;
+ float sqrt_2_delta = fputil::sqrt<float>(2.0 * delta);
+ float x2 = delta;
+ float pe = fputil::polyeval(x2, 0x1.0000000000000p+0f,
+ -0x1.55551a83a9472p-4f, 0x1.331601c4b8ecfp-6f,
+ -0x1.6890f49eb0acbp-8f, 0x1.8f3a617040a6ap-10f);
+ float approx = sqrt_2_delta * pe;
+ return fputil::cast<float16>(approx);
+ }
- // Special optimization for large input values.
- // if (LIBC_UNLIKELY(xf32 >= 32.0f)) {
- // float result = static_cast<float>(log_eval(2.0f * xf32));
- // return fputil::cast<float16>(result);
- // }
+ if (auto r = ACOSHF16_EXCEPTS.lookup(xbits.uintval());
+ LIBC_UNLIKELY(r.has_value()))
+ return r.value();
// Standard computation for general case.
float sqrt_term =
diff --git a/libc/test/src/math/acoshf16_test.cpp b/libc/test/src/math/acoshf16_test.cpp
index 84574a565b9be..a68b0742be03e 100644
--- a/libc/test/src/math/acoshf16_test.cpp
+++ b/libc/test/src/math/acoshf16_test.cpp
@@ -48,7 +48,7 @@ TEST_F(LlvmLibcAcoshf16Test, PositiveRange) {
float16 x = FPBits(v).get_val();
EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Acosh, x,
- LIBC_NAMESPACE::acoshf16(x), 3.0);
+ LIBC_NAMESPACE::acoshf16(x), 1.0);
}
}
>From 3922002b6bf895be8900ef550be78260bba345c2 Mon Sep 17 00:00:00 2001
From: Harrison Hao <tsworld1314 at gmail.com>
Date: Thu, 13 Mar 2025 12:51:55 +0000
Subject: [PATCH 8/8] [libc][math][c23] Reduce MPFR to 0.5.
---
libc/src/math/generic/acoshf16.cpp | 14 +++++++-------
libc/test/src/math/acoshf16_test.cpp | 2 +-
2 files changed, 8 insertions(+), 8 deletions(-)
diff --git a/libc/src/math/generic/acoshf16.cpp b/libc/src/math/generic/acoshf16.cpp
index c133026f8f445..1a4f68987ee6b 100644
--- a/libc/src/math/generic/acoshf16.cpp
+++ b/libc/src/math/generic/acoshf16.cpp
@@ -18,10 +18,11 @@
namespace LIBC_NAMESPACE_DECL {
-static constexpr size_t N_EXCEPTS = 1;
+static constexpr size_t N_EXCEPTS = 2;
static constexpr fputil::ExceptValues<float16, N_EXCEPTS> ACOSHF16_EXCEPTS{
{// (input, RZ output, RU offset, RD offset, RN offset)
- {0x41B7, 0x3ED8, 0, 1, 0}}};
+ {0x41B7, 0x3ED8, 1, 0, 0},
+ {0x3CE4, 0x393E, 1, 0, 1}}};
LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
using FPBits = fputil::FPBits<float16>;
@@ -59,8 +60,11 @@ LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
if (LIBC_UNLIKELY(x_u == 0x3c00U))
return float16(0.0f);
- float xf32 = x;
+ if (auto r = ACOSHF16_EXCEPTS.lookup(xbits.uintval());
+ LIBC_UNLIKELY(r.has_value()))
+ return r.value();
+ float xf32 = x;
// High precision for inputs very close to 1.0
if (LIBC_UNLIKELY(xf32 < 1.25f)) {
float delta = xf32 - 1.0f;
@@ -73,10 +77,6 @@ LLVM_LIBC_FUNCTION(float16, acoshf16, (float16 x)) {
return fputil::cast<float16>(approx);
}
- if (auto r = ACOSHF16_EXCEPTS.lookup(xbits.uintval());
- LIBC_UNLIKELY(r.has_value()))
- return r.value();
-
// Standard computation for general case.
float sqrt_term =
fputil::sqrt<float>(fputil::multiply_add(xf32, xf32, -1.0f));
diff --git a/libc/test/src/math/acoshf16_test.cpp b/libc/test/src/math/acoshf16_test.cpp
index a68b0742be03e..a779d3110f329 100644
--- a/libc/test/src/math/acoshf16_test.cpp
+++ b/libc/test/src/math/acoshf16_test.cpp
@@ -48,7 +48,7 @@ TEST_F(LlvmLibcAcoshf16Test, PositiveRange) {
float16 x = FPBits(v).get_val();
EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Acosh, x,
- LIBC_NAMESPACE::acoshf16(x), 1.0);
+ LIBC_NAMESPACE::acoshf16(x), 0.5);
}
}
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