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implement tanpif
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12 files changed

+248
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‎libc/config/linux/aarch64/entrypoints.txt‎

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@@ -625,6 +625,7 @@ set(TARGET_LIBM_ENTRYPOINTS
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libc.src.math.tan
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libc.src.math.tanf
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libc.src.math.tanhf
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libc.src.math.tanpif
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libc.src.math.totalorder
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libc.src.math.totalorderf
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libc.src.math.totalorderl

‎libc/config/linux/x86_64/entrypoints.txt‎

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@@ -657,6 +657,7 @@ set(TARGET_LIBM_ENTRYPOINTS
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libc.src.math.tan
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libc.src.math.tanf
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libc.src.math.tanhf
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libc.src.math.tanpif
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libc.src.math.totalorder
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libc.src.math.totalorderf
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libc.src.math.totalorderl

‎libc/docs/headers/math/index.rst‎

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@@ -349,7 +349,7 @@ Higher Math Functions
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+-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
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| tanh | |check| | | | |check| | | 7.12.5.6 | F.10.2.6 |
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+-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
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| tanpi | | | | |check| | | 7.12.4.14 | F.10.1.14 |
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| tanpi | |check| | | | |check| | | 7.12.4.14 | F.10.1.14 |
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+-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
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| tgamma | | | | | | 7.12.8.4 | F.10.5.4 |
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+-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+

‎libc/include/math.yaml‎

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@@ -2524,6 +2524,12 @@ functions:
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arguments:
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- type: _Float16
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guard: LIBC_TYPES_HAS_FLOAT16
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- name: tanpif
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standards:
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- stdc
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return_type: float
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arguments:
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- type: float
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- name: tanpif16
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standards:
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- stdc

‎libc/src/math/CMakeLists.txt‎

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@@ -519,6 +519,8 @@ add_math_entrypoint_object(tanf16)
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add_math_entrypoint_object(tanh)
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add_math_entrypoint_object(tanhf)
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add_math_entrypoint_object(tanhf16)
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add_math_entrypoint_object(tanpif)
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add_math_entrypoint_object(tanpif16)
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add_math_entrypoint_object(tgamma)

‎libc/src/math/generic/CMakeLists.txt‎

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@@ -606,6 +606,21 @@ add_entrypoint_object(
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libc.src.__support.macros.properties.types
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)
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add_entrypoint_object(
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tanpif
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SRCS
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tanpif.cpp
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HDRS
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../tanpif.h
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DEPENDS
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.sincosf_utils
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libc.src.__support.FPUtil.except_value_utils
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libc.src.__support.FPUtil.fenv_impl
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libc.src.__support.FPUtil.fp_bits
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libc.src.__support.FPUtil.multiply_add
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libc.src.__support.macros.optimization
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)
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add_entrypoint_object(
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tanpif16
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SRCS

‎libc/src/math/generic/tanpif.cpp‎

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//===-- Single-precision tanpi function -----------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#include "src/math/tanpif.h"
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#include "sincosf_utils.h"
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#include "src/__support/FPUtil/FEnvImpl.h"
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#include "src/__support/FPUtil/FPBits.h"
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#include "src/__support/FPUtil/cast.h"
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#include "src/__support/FPUtil/except_value_utils.h"
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#include "src/__support/FPUtil/multiply_add.h"
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#include "src/__support/common.h"
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#include "src/__support/macros/config.h"
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#include "src/__support/macros/optimization.h" // LIBC_UNLIKELY
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namespace LIBC_NAMESPACE_DECL {
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#ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
23+
constexpr size_t N_EXCEPTS = 3;
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constexpr fputil::ExceptValues<float, N_EXCEPTS> TANPIF_EXCEPTS{{
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// (input, RZ output, RU offset, RD offset, RN offset)
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{0x38F26685, 0x39BE6182, 1, 0, 0},
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{0x3E933802, 0x3FA267DD, 1, 0, 0},
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{0x3F3663FF, 0xBFA267DD, 0, 1, 0},
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}};
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#endif // !LIBC_MATH_HAS_SKIP_ACCURATE_PASS
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LLVM_LIBC_FUNCTION(float, tanpif, (float x)) {
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using FPBits = typename fputil::FPBits<float>;
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FPBits xbits(x);
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uint32_t x_u = xbits.uintval();
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uint32_t x_abs = x_u & 0x7fff'ffffU;
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double xd = static_cast<double>(xbits.get_val());
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// Handle exceptional values
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if (LIBC_UNLIKELY(x_abs <= 0x3F3663FF)) {
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if (LIBC_UNLIKELY(x_abs == 0U))
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return x;
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#ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
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bool x_sign = x_u >> 31;
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if (auto r = TANPIF_EXCEPTS.lookup_odd(x_abs, x_sign);
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LIBC_UNLIKELY(r.has_value()))
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return r.value();
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#endif // !LIBC_MATH_HAS_SKIP_ACCURATE_PASS
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}
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// Numbers greater or equal to 2^23 are always integers, or infinity, or NaN
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if (LIBC_UNLIKELY(x_abs >= 0x4B00'0000)) {
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// x is inf or NaN.
58+
if (LIBC_UNLIKELY(x_abs >= 0x7f80'0000U)) {
59+
if (xbits.is_signaling_nan()) {
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fputil::raise_except_if_required(FE_INVALID);
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return FPBits::quiet_nan().get_val();
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}
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if (x_abs == 0x7f80'0000U) {
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fputil::set_errno_if_required(EDOM);
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fputil::raise_except_if_required(FE_INVALID);
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}
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return x + FPBits::quiet_nan().get_val();
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}
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return FPBits::zero(xbits.sign()).get_val();
73+
}
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// Range reduction:
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// For |x| > 1/32, we perform range reduction as follows:
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// Find k and y such that:
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// x = (k + y) * 1/32
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// k is an integer
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// |y| < 0.5
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//
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// This is done by performing:
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// k = round(x * 32)
84+
// y = x * 32 - k
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//
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// Once k and y are computed, we then deduce the answer by the formula:
87+
// tan(x) = sin(x) / cos(x)
88+
// = (sin_y * cos_k + cos_y * sin_k) / (cos_y * cos_k - sin_y * sin_k)
89+
double sin_k, cos_k, sin_y, cosm1_y;
90+
sincospif_eval(xd, sin_k, cos_k, sin_y, cosm1_y);
91+
92+
if (LIBC_UNLIKELY(sin_y == 0 && cos_k == 0)) {
93+
fputil::set_errno_if_required(EDOM);
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fputil::raise_except_if_required(FE_DIVBYZERO);
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96+
int32_t x_mp5_u = static_cast<int32_t>(x - 0.5);
97+
return ((x_mp5_u & 0x1) ? -1 : 1) * FPBits::inf().get_val();
98+
}
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using fputil::multiply_add;
101+
return fputil::cast<float>(
102+
multiply_add(sin_y, cos_k, multiply_add(cosm1_y, sin_k, sin_k)) /
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multiply_add(sin_y, -sin_k, multiply_add(cosm1_y, cos_k, cos_k)));
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}
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} // namespace LIBC_NAMESPACE_DECL

‎libc/src/math/tanpif.h‎

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//===-- Implementation header for tanpif ------------------------*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_LIBC_SRC_MATH_TANPIF_H
10+
#define LLVM_LIBC_SRC_MATH_TANPIF_H
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#include "src/__support/macros/config.h"
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namespace LIBC_NAMESPACE_DECL {
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float tanpif(float x);
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} // namespace LIBC_NAMESPACE_DECL
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#endif // LLVM_LIBC_SRC_MATH_TANPIF_H

‎libc/test/src/math/exhaustive/CMakeLists.txt‎

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@@ -122,6 +122,22 @@ add_fp_unittest(
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-lpthread
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)
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125+
add_fp_unittest(
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tanpif_test
127+
NO_RUN_POSTBUILD
128+
NEED_MPFR
129+
SUITE
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libc_math_exhaustive_tests
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SRCS
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tanpif_test.cpp
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DEPENDS
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.exhaustive_test
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libc.src.math.tanpif
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libc.src.__support.FPUtil.fp_bits
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LINK_LIBRARIES
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-lpthread
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)
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add_fp_unittest(
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erff_test
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NO_RUN_POSTBUILD

‎libc/test/src/math/exhaustive/tanpif_test.cpp‎

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1+
//===-- Exhaustive test for tanpif ----------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4+
// See https://llvm.org/LICENSE.txt for license information.
5+
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
7+
//===----------------------------------------------------------------------===//
8+
9+
#include "exhaustive_test.h"
10+
#include "src/math/tanpif.h"
11+
#include "utils/MPFRWrapper/MPFRUtils.h"
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13+
namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
14+
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using LlvmLibcTanpifExhaustiveTest =
16+
LlvmLibcUnaryOpExhaustiveMathTest<float, mpfr::Operation::Tanpi,
17+
LIBC_NAMESPACE::tanpif>;
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19+
// Range: [0, Inf];
20+
static constexpr uint32_t POS_START = 0x0000'0000U;
21+
static constexpr uint32_t POS_STOP = 0x7f80'0000U;
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TEST_F(LlvmLibcTanpifExhaustiveTest, PostiveRange) {
24+
test_full_range_all_roundings(POS_START, POS_STOP);
25+
}
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// Range: [-Inf, 0];
28+
static constexpr uint32_t NEG_START = 0xb000'0000U;
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static constexpr uint32_t NEG_STOP = 0xff80'0000U;
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31+
TEST_F(LlvmLibcTanpifExhaustiveTest, NegativeRange) {
32+
test_full_range_all_roundings(NEG_START, NEG_STOP);
33+
}

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