[libc-commits] [libc] [llvm] [libc][math] Refactor sincos implementation to header only (PR #177522)
via libc-commits
libc-commits at lists.llvm.org
Mon Jan 26 21:11:59 PST 2026
https://github.com/tnuha updated https://github.com/llvm/llvm-project/pull/177522
>From c2ca2c419dc1241fa1e39c69df6c42324b813da2 Mon Sep 17 00:00:00 2001
From: ash <ashkernel02 at gmail.com>
Date: Thu, 22 Jan 2026 15:19:36 -0700
Subject: [PATCH 01/13] [libc][math] Refactor sincos implementation to header
only in src/__support/math directory. Part of llvm#147386
in preparation for: https://discourse.llvm.org/t/rfc-make-clang-builtin-math-functions-constexpr-with-llvm-libc-to-support-c-23-constexpr-math-functions/86450
---
libc/shared/math.h | 1 +
libc/shared/math/sincos.h | 23 +++
libc/src/__support/math/CMakeLists.txt | 21 +++
libc/src/__support/math/sincos.h | 232 +++++++++++++++++++++++++
libc/src/math/generic/sincos.cpp | 210 +---------------------
5 files changed, 279 insertions(+), 208 deletions(-)
create mode 100644 libc/shared/math/sincos.h
create mode 100644 libc/src/__support/math/sincos.h
diff --git a/libc/shared/math.h b/libc/shared/math.h
index 6b66c5e75e457..a9c356cf8708c 100644
--- a/libc/shared/math.h
+++ b/libc/shared/math.h
@@ -78,5 +78,6 @@
#include "math/rsqrtf.h"
#include "math/rsqrtf16.h"
#include "math/sin.h"
+#include "math/sincos.h"
#endif // LLVM_LIBC_SHARED_MATH_H
diff --git a/libc/shared/math/sincos.h b/libc/shared/math/sincos.h
new file mode 100644
index 0000000000000..fec49a02feb12
--- /dev/null
+++ b/libc/shared/math/sincos.h
@@ -0,0 +1,23 @@
+//===-- Shared sincos 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_SINCOS_H
+#define LLVM_LIBC_SHARED_MATH_SINCOS_H
+
+#include "shared/libc_common.h"
+#include "src/__support/math/sincos.h"
+
+namespace LIBC_NAMESPACE_DECL {
+namespace shared {
+
+using math::sincos;
+
+} // namespace shared
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SHARED_MATH_SINCOS_H
diff --git a/libc/src/__support/math/CMakeLists.txt b/libc/src/__support/math/CMakeLists.txt
index 0e7a082434fb5..5e9a1d76ef875 100644
--- a/libc/src/__support/math/CMakeLists.txt
+++ b/libc/src/__support/math/CMakeLists.txt
@@ -1053,6 +1053,27 @@ add_header_library(
libc.src.__support.macros.optimization
)
+add_header_library(
+ sincos
+ HDRS
+ sincos.h
+ DEPENDS
+ libc.hdr.errno_macros
+ src.__support.FPUtil.FEnvImpl
+ src.__support.FPUtil.FPBits
+ src.__support.FPUtil.double_double
+ src.__support.FPUtil.dyadic_float
+ src.__support.FPUtil.except_value_utils
+ src.__support.FPUtil.multiply_add
+ src.__support.FPUtil.rounding_mode
+ src.__support.common
+ src.__support.macros.config
+ src.__support.macros.optimization
+ src.__support.macros.properties.cpu_features
+ src.__support.math.range_reduction_double_common
+ src.__support.math.sincos_eval
+)
+
add_header_library(
sincos_eval
HDRS
diff --git a/libc/src/__support/math/sincos.h b/libc/src/__support/math/sincos.h
new file mode 100644
index 0000000000000..4e4be20e2b30f
--- /dev/null
+++ b/libc/src/__support/math/sincos.h
@@ -0,0 +1,232 @@
+//===-- Implementation header for sincos ------------------------*- 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_SINCOS_H
+#define LLVM_LIBC_SRC___SUPPORT_MATH_SINCOS_H
+
+#include "hdr/errno_macros.h"
+#include "range_reduction_double_common.h"
+#include "sincos_eval.h"
+#include "src/__support/FPUtil/FEnvImpl.h"
+#include "src/__support/FPUtil/FPBits.h"
+#include "src/__support/FPUtil/double_double.h"
+#include "src/__support/FPUtil/dyadic_float.h"
+#include "src/__support/FPUtil/except_value_utils.h"
+#include "src/__support/FPUtil/multiply_add.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" // LIBC_UNLIKELY
+#include "src/__support/macros/properties/cpu_features.h" // LIBC_TARGET_CPU_HAS_FMA
+
+#ifdef LIBC_TARGET_CPU_HAS_FMA_DOUBLE
+#include "src/__support/math/range_reduction_double_fma.h"
+#else
+#include "src/__support/math/range_reduction_double_nofma.h"
+#endif // LIBC_TARGET_CPU_HAS_FMA_DOUBLE
+
+namespace LIBC_NAMESPACE_DECL {
+
+namespace math {
+
+using DoubleDouble = fputil::DoubleDouble;
+using Float128 = typename fputil::DyadicFloat<128>;
+
+// LLVM_LIBC_FUNCTION(void, sincos, (double x, double *sin_x, double *cos_x)) {
+static constexpr void sincos(double x, double *sin_x, double *cos_x) {
+ using namespace math::range_reduction_double_internal;
+ using FPBits = typename fputil::FPBits<double>;
+ FPBits xbits(x);
+
+ uint16_t x_e = xbits.get_biased_exponent();
+
+ DoubleDouble y;
+ unsigned k = 0;
+ LargeRangeReduction range_reduction_large{};
+
+ // |x| < 2^16
+ if (LIBC_LIKELY(x_e < FPBits::EXP_BIAS + FAST_PASS_EXPONENT)) {
+ // |x| < 2^-7
+ if (LIBC_UNLIKELY(x_e < FPBits::EXP_BIAS - 7)) {
+ // |x| < 2^-27
+ if (LIBC_UNLIKELY(x_e < FPBits::EXP_BIAS - 27)) {
+ // Signed zeros.
+ if (LIBC_UNLIKELY(x == 0.0)) {
+ *sin_x = x;
+ *cos_x = 1.0;
+ return;
+ }
+
+ // For |x| < 2^-27, max(|sin(x) - x|, |cos(x) - 1|) < ulp(x)/2.
+#ifdef LIBC_TARGET_CPU_HAS_FMA_DOUBLE
+ *sin_x = fputil::multiply_add(x, -0x1.0p-54, x);
+ *cos_x = fputil::multiply_add(x, -x, 1.0);
+#else
+ *cos_x = fputil::round_result_slightly_down(1.0);
+
+ if (LIBC_UNLIKELY(x_e < 4)) {
+ int rounding_mode = fputil::quick_get_round();
+ if (rounding_mode == FE_TOWARDZERO ||
+ (xbits.sign() == Sign::POS && rounding_mode == FE_DOWNWARD) ||
+ (xbits.sign() == Sign::NEG && rounding_mode == FE_UPWARD))
+ *sin_x = FPBits(xbits.uintval() - 1).get_val();
+ }
+ *sin_x = fputil::multiply_add(x, -0x1.0p-54, x);
+#endif // LIBC_TARGET_CPU_HAS_FMA_DOUBLE
+ return;
+ }
+ // No range reduction needed.
+ k = 0;
+ y.lo = 0.0;
+ y.hi = x;
+ } else {
+ // Small range reduction.
+ k = range_reduction_small(x, y);
+ }
+ } else {
+ // Inf or NaN
+ if (LIBC_UNLIKELY(x_e > 2 * FPBits::EXP_BIAS)) {
+ if (xbits.is_signaling_nan()) {
+ fputil::raise_except_if_required(FE_INVALID);
+ *sin_x = *cos_x = FPBits::quiet_nan().get_val();
+ return;
+ }
+
+ // sin(+-Inf) = NaN
+ if (xbits.get_mantissa() == 0) {
+ fputil::set_errno_if_required(EDOM);
+ fputil::raise_except_if_required(FE_INVALID);
+ }
+ *sin_x = *cos_x = x + FPBits::quiet_nan().get_val();
+ return;
+ }
+
+ // Large range reduction.
+ k = range_reduction_large.fast(x, y);
+ }
+
+ DoubleDouble sin_y, cos_y;
+
+ [[maybe_unused]] double err =
+ math::sincos_eval_internal::sincos_eval(y, sin_y, cos_y);
+
+ // Look up sin(k * pi/128) and cos(k * pi/128)
+#ifdef LIBC_MATH_HAS_SMALL_TABLES
+ // Memory saving versions. Use 65-entry table.
+ auto get_idx_dd = [](unsigned kk) -> DoubleDouble {
+ unsigned idx = (kk & 64) ? 64 - (kk & 63) : (kk & 63);
+ DoubleDouble ans = SIN_K_PI_OVER_128[idx];
+ if (kk & 128) {
+ ans.hi = -ans.hi;
+ ans.lo = -ans.lo;
+ }
+ return ans;
+ };
+ DoubleDouble sin_k = get_idx_dd(k);
+ DoubleDouble cos_k = get_idx_dd(k + 64);
+#else
+ // Fast look up version, but needs 256-entry table.
+ // cos(k * pi/128) = sin(k * pi/128 + pi/2) = sin((k + 64) * pi/128).
+ DoubleDouble sin_k = SIN_K_PI_OVER_128[k & 255];
+ DoubleDouble cos_k = SIN_K_PI_OVER_128[(k + 64) & 255];
+#endif // LIBC_MATH_HAS_SMALL_TABLES
+
+ DoubleDouble msin_k{-sin_k.lo, -sin_k.hi};
+
+ // After range reduction, k = round(x * 128 / pi) and y = x - k * (pi / 128).
+ // So k is an integer and -pi / 256 <= y <= pi / 256.
+ // Then sin(x) = sin((k * pi/128 + y)
+ // = sin(y) * cos(k*pi/128) + cos(y) * sin(k*pi/128)
+ DoubleDouble sin_k_cos_y = fputil::quick_mult(cos_y, sin_k);
+ DoubleDouble cos_k_sin_y = fputil::quick_mult(sin_y, cos_k);
+ // cos(x) = cos((k * pi/128 + y)
+ // = cos(y) * cos(k*pi/128) - sin(y) * sin(k*pi/128)
+ DoubleDouble cos_k_cos_y = fputil::quick_mult(cos_y, cos_k);
+ DoubleDouble msin_k_sin_y = fputil::quick_mult(sin_y, msin_k);
+
+ DoubleDouble sin_dd =
+ fputil::exact_add<false>(sin_k_cos_y.hi, cos_k_sin_y.hi);
+ DoubleDouble cos_dd =
+ fputil::exact_add<false>(cos_k_cos_y.hi, msin_k_sin_y.hi);
+ sin_dd.lo += sin_k_cos_y.lo + cos_k_sin_y.lo;
+ cos_dd.lo += msin_k_sin_y.lo + cos_k_cos_y.lo;
+
+#ifdef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
+ *sin_x = sin_dd.hi + sin_dd.lo;
+ *cos_x = cos_dd.hi + cos_dd.lo;
+ return;
+#else
+ // Accurate test and pass for correctly rounded implementation.
+
+ double sin_lp = sin_dd.lo + err;
+ double sin_lm = sin_dd.lo - err;
+ double cos_lp = cos_dd.lo + err;
+ double cos_lm = cos_dd.lo - err;
+
+ double sin_upper = sin_dd.hi + sin_lp;
+ double sin_lower = sin_dd.hi + sin_lm;
+ double cos_upper = cos_dd.hi + cos_lp;
+ double cos_lower = cos_dd.hi + cos_lm;
+
+ // Ziv's rounding test.
+ if (LIBC_LIKELY(sin_upper == sin_lower && cos_upper == cos_lower)) {
+ *sin_x = sin_upper;
+ *cos_x = cos_upper;
+ return;
+ }
+
+ Float128 u_f128, sin_u, cos_u;
+ if (LIBC_LIKELY(x_e < FPBits::EXP_BIAS + FAST_PASS_EXPONENT))
+ u_f128 = range_reduction_small_f128(x);
+ else
+ u_f128 = range_reduction_large.accurate();
+
+ math::sincos_eval_internal::sincos_eval(u_f128, sin_u, cos_u);
+
+ auto get_sin_k = [](unsigned kk) -> Float128 {
+ unsigned idx = (kk & 64) ? 64 - (kk & 63) : (kk & 63);
+ Float128 ans = SIN_K_PI_OVER_128_F128[idx];
+ if (kk & 128)
+ ans.sign = Sign::NEG;
+ return ans;
+ };
+
+ // cos(k * pi/128) = sin(k * pi/128 + pi/2) = sin((k + 64) * pi/128).
+ Float128 sin_k_f128 = get_sin_k(k);
+ Float128 cos_k_f128 = get_sin_k(k + 64);
+ Float128 msin_k_f128 = get_sin_k(k + 128);
+
+ // TODO: Add assertion if Ziv's accuracy tests fail in debug mode.
+ // https://github.com/llvm/llvm-project/issues/96452.
+
+ if (sin_upper == sin_lower)
+ *sin_x = sin_upper;
+ else
+ // sin(x) = sin((k * pi/128 + u)
+ // = sin(u) * cos(k*pi/128) + cos(u) * sin(k*pi/128)
+ *sin_x = static_cast<double>(
+ fputil::quick_add(fputil::quick_mul(sin_k_f128, cos_u),
+ fputil::quick_mul(cos_k_f128, sin_u)));
+
+ if (cos_upper == cos_lower)
+ *cos_x = cos_upper;
+ else
+ // cos(x) = cos((k * pi/128 + u)
+ // = cos(u) * cos(k*pi/128) - sin(u) * sin(k*pi/128)
+ *cos_x = static_cast<double>(
+ fputil::quick_add(fputil::quick_mul(cos_k_f128, cos_u),
+ fputil::quick_mul(msin_k_f128, sin_u)));
+
+#endif // !LIBC_MATH_HAS_SKIP_ACCURATE_PASS
+}
+
+} // namespace math
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC___SUPPORT_MATH_SINCOS_H
diff --git a/libc/src/math/generic/sincos.cpp b/libc/src/math/generic/sincos.cpp
index 38661deaa886a..346531ea53255 100644
--- a/libc/src/math/generic/sincos.cpp
+++ b/libc/src/math/generic/sincos.cpp
@@ -6,218 +6,12 @@
//
//===----------------------------------------------------------------------===//
+#include "src/__support/math/sincos.h"
#include "src/math/sincos.h"
-#include "hdr/errno_macros.h"
-#include "src/__support/FPUtil/FEnvImpl.h"
-#include "src/__support/FPUtil/FPBits.h"
-#include "src/__support/FPUtil/double_double.h"
-#include "src/__support/FPUtil/dyadic_float.h"
-#include "src/__support/FPUtil/except_value_utils.h"
-#include "src/__support/FPUtil/multiply_add.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" // LIBC_UNLIKELY
-#include "src/__support/macros/properties/cpu_features.h" // LIBC_TARGET_CPU_HAS_FMA
-#include "src/__support/math/range_reduction_double_common.h"
-#include "src/__support/math/sincos_eval.h"
-
-#ifdef LIBC_TARGET_CPU_HAS_FMA_DOUBLE
-#include "src/__support/math/range_reduction_double_fma.h"
-#else
-#include "src/__support/math/range_reduction_double_nofma.h"
-#endif // LIBC_TARGET_CPU_HAS_FMA_DOUBLE
namespace LIBC_NAMESPACE_DECL {
-
-using DoubleDouble = fputil::DoubleDouble;
-using Float128 = typename fputil::DyadicFloat<128>;
-
LLVM_LIBC_FUNCTION(void, sincos, (double x, double *sin_x, double *cos_x)) {
- using namespace math::range_reduction_double_internal;
- using FPBits = typename fputil::FPBits<double>;
- FPBits xbits(x);
-
- uint16_t x_e = xbits.get_biased_exponent();
-
- DoubleDouble y;
- unsigned k;
- LargeRangeReduction range_reduction_large{};
-
- // |x| < 2^16
- if (LIBC_LIKELY(x_e < FPBits::EXP_BIAS + FAST_PASS_EXPONENT)) {
- // |x| < 2^-7
- if (LIBC_UNLIKELY(x_e < FPBits::EXP_BIAS - 7)) {
- // |x| < 2^-27
- if (LIBC_UNLIKELY(x_e < FPBits::EXP_BIAS - 27)) {
- // Signed zeros.
- if (LIBC_UNLIKELY(x == 0.0)) {
- *sin_x = x;
- *cos_x = 1.0;
- return;
- }
-
- // For |x| < 2^-27, max(|sin(x) - x|, |cos(x) - 1|) < ulp(x)/2.
-#ifdef LIBC_TARGET_CPU_HAS_FMA_DOUBLE
- *sin_x = fputil::multiply_add(x, -0x1.0p-54, x);
- *cos_x = fputil::multiply_add(x, -x, 1.0);
-#else
- *cos_x = fputil::round_result_slightly_down(1.0);
-
- if (LIBC_UNLIKELY(x_e < 4)) {
- int rounding_mode = fputil::quick_get_round();
- if (rounding_mode == FE_TOWARDZERO ||
- (xbits.sign() == Sign::POS && rounding_mode == FE_DOWNWARD) ||
- (xbits.sign() == Sign::NEG && rounding_mode == FE_UPWARD))
- *sin_x = FPBits(xbits.uintval() - 1).get_val();
- }
- *sin_x = fputil::multiply_add(x, -0x1.0p-54, x);
-#endif // LIBC_TARGET_CPU_HAS_FMA_DOUBLE
- return;
- }
- // No range reduction needed.
- k = 0;
- y.lo = 0.0;
- y.hi = x;
- } else {
- // Small range reduction.
- k = range_reduction_small(x, y);
- }
- } else {
- // Inf or NaN
- if (LIBC_UNLIKELY(x_e > 2 * FPBits::EXP_BIAS)) {
- if (xbits.is_signaling_nan()) {
- fputil::raise_except_if_required(FE_INVALID);
- *sin_x = *cos_x = FPBits::quiet_nan().get_val();
- return;
- }
-
- // sin(+-Inf) = NaN
- if (xbits.get_mantissa() == 0) {
- fputil::set_errno_if_required(EDOM);
- fputil::raise_except_if_required(FE_INVALID);
- }
- *sin_x = *cos_x = x + FPBits::quiet_nan().get_val();
- return;
- }
-
- // Large range reduction.
- k = range_reduction_large.fast(x, y);
- }
-
- DoubleDouble sin_y, cos_y;
-
- [[maybe_unused]] double err =
- math::sincos_eval_internal::sincos_eval(y, sin_y, cos_y);
-
- // Look up sin(k * pi/128) and cos(k * pi/128)
-#ifdef LIBC_MATH_HAS_SMALL_TABLES
- // Memory saving versions. Use 65-entry table.
- auto get_idx_dd = [](unsigned kk) -> DoubleDouble {
- unsigned idx = (kk & 64) ? 64 - (kk & 63) : (kk & 63);
- DoubleDouble ans = SIN_K_PI_OVER_128[idx];
- if (kk & 128) {
- ans.hi = -ans.hi;
- ans.lo = -ans.lo;
- }
- return ans;
- };
- DoubleDouble sin_k = get_idx_dd(k);
- DoubleDouble cos_k = get_idx_dd(k + 64);
-#else
- // Fast look up version, but needs 256-entry table.
- // cos(k * pi/128) = sin(k * pi/128 + pi/2) = sin((k + 64) * pi/128).
- DoubleDouble sin_k = SIN_K_PI_OVER_128[k & 255];
- DoubleDouble cos_k = SIN_K_PI_OVER_128[(k + 64) & 255];
-#endif // LIBC_MATH_HAS_SMALL_TABLES
-
- DoubleDouble msin_k{-sin_k.lo, -sin_k.hi};
-
- // After range reduction, k = round(x * 128 / pi) and y = x - k * (pi / 128).
- // So k is an integer and -pi / 256 <= y <= pi / 256.
- // Then sin(x) = sin((k * pi/128 + y)
- // = sin(y) * cos(k*pi/128) + cos(y) * sin(k*pi/128)
- DoubleDouble sin_k_cos_y = fputil::quick_mult(cos_y, sin_k);
- DoubleDouble cos_k_sin_y = fputil::quick_mult(sin_y, cos_k);
- // cos(x) = cos((k * pi/128 + y)
- // = cos(y) * cos(k*pi/128) - sin(y) * sin(k*pi/128)
- DoubleDouble cos_k_cos_y = fputil::quick_mult(cos_y, cos_k);
- DoubleDouble msin_k_sin_y = fputil::quick_mult(sin_y, msin_k);
-
- DoubleDouble sin_dd =
- fputil::exact_add<false>(sin_k_cos_y.hi, cos_k_sin_y.hi);
- DoubleDouble cos_dd =
- fputil::exact_add<false>(cos_k_cos_y.hi, msin_k_sin_y.hi);
- sin_dd.lo += sin_k_cos_y.lo + cos_k_sin_y.lo;
- cos_dd.lo += msin_k_sin_y.lo + cos_k_cos_y.lo;
-
-#ifdef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
- *sin_x = sin_dd.hi + sin_dd.lo;
- *cos_x = cos_dd.hi + cos_dd.lo;
- return;
-#else
- // Accurate test and pass for correctly rounded implementation.
-
- double sin_lp = sin_dd.lo + err;
- double sin_lm = sin_dd.lo - err;
- double cos_lp = cos_dd.lo + err;
- double cos_lm = cos_dd.lo - err;
-
- double sin_upper = sin_dd.hi + sin_lp;
- double sin_lower = sin_dd.hi + sin_lm;
- double cos_upper = cos_dd.hi + cos_lp;
- double cos_lower = cos_dd.hi + cos_lm;
-
- // Ziv's rounding test.
- if (LIBC_LIKELY(sin_upper == sin_lower && cos_upper == cos_lower)) {
- *sin_x = sin_upper;
- *cos_x = cos_upper;
- return;
- }
-
- Float128 u_f128, sin_u, cos_u;
- if (LIBC_LIKELY(x_e < FPBits::EXP_BIAS + FAST_PASS_EXPONENT))
- u_f128 = range_reduction_small_f128(x);
- else
- u_f128 = range_reduction_large.accurate();
-
- math::sincos_eval_internal::sincos_eval(u_f128, sin_u, cos_u);
-
- auto get_sin_k = [](unsigned kk) -> Float128 {
- unsigned idx = (kk & 64) ? 64 - (kk & 63) : (kk & 63);
- Float128 ans = SIN_K_PI_OVER_128_F128[idx];
- if (kk & 128)
- ans.sign = Sign::NEG;
- return ans;
- };
-
- // cos(k * pi/128) = sin(k * pi/128 + pi/2) = sin((k + 64) * pi/128).
- Float128 sin_k_f128 = get_sin_k(k);
- Float128 cos_k_f128 = get_sin_k(k + 64);
- Float128 msin_k_f128 = get_sin_k(k + 128);
-
- // TODO: Add assertion if Ziv's accuracy tests fail in debug mode.
- // https://github.com/llvm/llvm-project/issues/96452.
-
- if (sin_upper == sin_lower)
- *sin_x = sin_upper;
- else
- // sin(x) = sin((k * pi/128 + u)
- // = sin(u) * cos(k*pi/128) + cos(u) * sin(k*pi/128)
- *sin_x = static_cast<double>(
- fputil::quick_add(fputil::quick_mul(sin_k_f128, cos_u),
- fputil::quick_mul(cos_k_f128, sin_u)));
-
- if (cos_upper == cos_lower)
- *cos_x = cos_upper;
- else
- // cos(x) = cos((k * pi/128 + u)
- // = cos(u) * cos(k*pi/128) - sin(u) * sin(k*pi/128)
- *cos_x = static_cast<double>(
- fputil::quick_add(fputil::quick_mul(cos_k_f128, cos_u),
- fputil::quick_mul(msin_k_f128, sin_u)));
-
-#endif // !LIBC_MATH_HAS_SKIP_ACCURATE_PASS
+ return math::sincos(x, sin_x, cos_x);
}
} // namespace LIBC_NAMESPACE_DECL
>From 9122894efe1dc014393a5ebfc88e54f715c59fc5 Mon Sep 17 00:00:00 2001
From: ash <ashkernel02 at gmail.com>
Date: Fri, 23 Jan 2026 08:08:18 -0700
Subject: [PATCH 02/13] inline, comment removed
---
libc/src/__support/math/sincos.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/libc/src/__support/math/sincos.h b/libc/src/__support/math/sincos.h
index 4e4be20e2b30f..b07149d11034b 100644
--- a/libc/src/__support/math/sincos.h
+++ b/libc/src/__support/math/sincos.h
@@ -37,8 +37,8 @@ namespace math {
using DoubleDouble = fputil::DoubleDouble;
using Float128 = typename fputil::DyadicFloat<128>;
-// LLVM_LIBC_FUNCTION(void, sincos, (double x, double *sin_x, double *cos_x)) {
-static constexpr void sincos(double x, double *sin_x, double *cos_x) {
+LIBC_INLINE static constexpr void sincos(double x, double *sin_x,
+ double *cos_x) {
using namespace math::range_reduction_double_internal;
using FPBits = typename fputil::FPBits<double>;
FPBits xbits(x);
>From 5aabdd696db9b5ca31f38b675c9c902ae2980029 Mon Sep 17 00:00:00 2001
From: ash <ashkernel02 at gmail.com>
Date: Fri, 23 Jan 2026 08:22:24 -0700
Subject: [PATCH 03/13] generic CMakeLists, manually updated BUILD.bazel
---
libc/src/math/generic/CMakeLists.txt | 12 +---------
.../llvm-project-overlay/libc/BUILD.bazel | 24 +++++++++++++++----
2 files changed, 20 insertions(+), 16 deletions(-)
diff --git a/libc/src/math/generic/CMakeLists.txt b/libc/src/math/generic/CMakeLists.txt
index bf799ce41363c..3a020b8ae65a5 100644
--- a/libc/src/math/generic/CMakeLists.txt
+++ b/libc/src/math/generic/CMakeLists.txt
@@ -413,17 +413,7 @@ add_entrypoint_object(
HDRS
../sincos.h
DEPENDS
- libc.src.__support.math.range_reduction_double
- libc.src.__support.math.sincos_eval
- libc.hdr.errno_macros
- libc.src.errno.errno
- libc.src.__support.FPUtil.double_double
- libc.src.__support.FPUtil.dyadic_float
- 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.macros.optimization
+ libc.src.__support.math.sincos
)
add_entrypoint_object(
diff --git a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
index 7251f491bc757..4139bd384120c 100644
--- a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
@@ -3259,6 +3259,24 @@ libc_support_library(
],
)
+libc_support_library(
+ name = "__support_math_sincos",
+ hdrs = ["src/__support/math/sincos.h"],
+ deps = [
+ ":__support_common",
+ ":__support_fputil_fenv_impl",
+ ":__support_fputil_fp_bits",
+ ":__support_fputil_double_double",
+ ":__support_fputil_dyadic_float",
+ ":__support_fputil_except_value_utils",
+ ":__support_fputil_multiply_add",
+ ":__support_fputil_rounding_mode",
+ ":__support_macros_optimization",
+ ":__support_macros_properties_cpu_features",
+ ":__support_macros_config"
+ ],
+)
+
libc_support_library(
name = "__support_sincos_eval",
hdrs = [
@@ -4927,11 +4945,7 @@ libc_math_function(
libc_math_function(
name = "sincos",
additional_deps = [
- ":__support_fputil_multiply_add",
- ":__support_macros_optimization",
- ":__support_macros_properties_cpu_features",
- ":__support_range_reduction_double",
- ":__support_sincos_eval",
+ ":__support_math_sincos",
],
)
>From a5ded227bf12dd35128e77c6829bcb67b25d6541 Mon Sep 17 00:00:00 2001
From: Ash <97464181+tnuha at users.noreply.github.com>
Date: Fri, 23 Jan 2026 22:13:05 +0000
Subject: [PATCH 04/13] Update libc/src/math/generic/sincos.cpp
Co-authored-by: Muhammad Bassiouni <60100307+bassiounix at users.noreply.github.com>
---
libc/src/math/generic/sincos.cpp | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/libc/src/math/generic/sincos.cpp b/libc/src/math/generic/sincos.cpp
index 346531ea53255..7306188650167 100644
--- a/libc/src/math/generic/sincos.cpp
+++ b/libc/src/math/generic/sincos.cpp
@@ -6,8 +6,8 @@
//
//===----------------------------------------------------------------------===//
-#include "src/__support/math/sincos.h"
#include "src/math/sincos.h"
+#include "src/__support/math/sincos.h"
namespace LIBC_NAMESPACE_DECL {
LLVM_LIBC_FUNCTION(void, sincos, (double x, double *sin_x, double *cos_x)) {
>From 3b795ea599014daedce66625ca6351df5fb062aa Mon Sep 17 00:00:00 2001
From: Ash <97464181+tnuha at users.noreply.github.com>
Date: Fri, 23 Jan 2026 22:13:15 +0000
Subject: [PATCH 05/13] Update libc/src/math/generic/CMakeLists.txt
Co-authored-by: Muhammad Bassiouni <60100307+bassiounix at users.noreply.github.com>
---
libc/src/math/generic/CMakeLists.txt | 1 +
1 file changed, 1 insertion(+)
diff --git a/libc/src/math/generic/CMakeLists.txt b/libc/src/math/generic/CMakeLists.txt
index 3a020b8ae65a5..745942a14f4fa 100644
--- a/libc/src/math/generic/CMakeLists.txt
+++ b/libc/src/math/generic/CMakeLists.txt
@@ -414,6 +414,7 @@ add_entrypoint_object(
../sincos.h
DEPENDS
libc.src.__support.math.sincos
+ libc.src.errno.errno
)
add_entrypoint_object(
>From bd6ecb7cc05b3a0843296de92fe1826b7997009d Mon Sep 17 00:00:00 2001
From: Ash <97464181+tnuha at users.noreply.github.com>
Date: Fri, 23 Jan 2026 22:13:28 +0000
Subject: [PATCH 06/13] Update libc/src/__support/math/sincos.h
Co-authored-by: Muhammad Bassiouni <60100307+bassiounix at users.noreply.github.com>
---
libc/src/__support/math/sincos.h | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/libc/src/__support/math/sincos.h b/libc/src/__support/math/sincos.h
index b07149d11034b..677ebfc480e53 100644
--- a/libc/src/__support/math/sincos.h
+++ b/libc/src/__support/math/sincos.h
@@ -34,11 +34,10 @@ namespace LIBC_NAMESPACE_DECL {
namespace math {
-using DoubleDouble = fputil::DoubleDouble;
-using Float128 = typename fputil::DyadicFloat<128>;
-
LIBC_INLINE static constexpr void sincos(double x, double *sin_x,
double *cos_x) {
+ using DoubleDouble = fputil::DoubleDouble;
+ using Float128 = typename fputil::DyadicFloat<128>;
using namespace math::range_reduction_double_internal;
using FPBits = typename fputil::FPBits<double>;
FPBits xbits(x);
>From e20a483e1ee4e27ae7bd5a42d5a718cfccc0795f Mon Sep 17 00:00:00 2001
From: Ash <97464181+tnuha at users.noreply.github.com>
Date: Fri, 23 Jan 2026 22:13:41 +0000
Subject: [PATCH 07/13] Update libc/src/__support/math/CMakeLists.txt
Co-authored-by: Muhammad Bassiouni <60100307+bassiounix at users.noreply.github.com>
---
libc/src/__support/math/CMakeLists.txt | 22 +++++++++-------------
1 file changed, 9 insertions(+), 13 deletions(-)
diff --git a/libc/src/__support/math/CMakeLists.txt b/libc/src/__support/math/CMakeLists.txt
index 5e9a1d76ef875..ee493fcda57eb 100644
--- a/libc/src/__support/math/CMakeLists.txt
+++ b/libc/src/__support/math/CMakeLists.txt
@@ -1058,20 +1058,16 @@ add_header_library(
HDRS
sincos.h
DEPENDS
+ .range_reduction_double
+ .sincos_eval
libc.hdr.errno_macros
- src.__support.FPUtil.FEnvImpl
- src.__support.FPUtil.FPBits
- src.__support.FPUtil.double_double
- src.__support.FPUtil.dyadic_float
- src.__support.FPUtil.except_value_utils
- src.__support.FPUtil.multiply_add
- src.__support.FPUtil.rounding_mode
- src.__support.common
- src.__support.macros.config
- src.__support.macros.optimization
- src.__support.macros.properties.cpu_features
- src.__support.math.range_reduction_double_common
- src.__support.math.sincos_eval
+ libc.src.__support.FPUtil.double_double
+ libc.src.__support.FPUtil.dyadic_float
+ 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.macros.optimization
)
add_header_library(
>From cce0e46aec2d9bfdaa243b4d80124fb07539043a Mon Sep 17 00:00:00 2001
From: ash <ashkernel02 at gmail.com>
Date: Sat, 24 Jan 2026 20:23:02 -0700
Subject: [PATCH 08/13] update shared
---
libc/test/shared/CMakeLists.txt | 1 +
libc/test/shared/shared_math_test.cpp | 4 ++++
2 files changed, 5 insertions(+)
diff --git a/libc/test/shared/CMakeLists.txt b/libc/test/shared/CMakeLists.txt
index 3be8f992aa486..aa65be4aafec3 100644
--- a/libc/test/shared/CMakeLists.txt
+++ b/libc/test/shared/CMakeLists.txt
@@ -74,4 +74,5 @@ add_fp_unittest(
libc.src.__support.math.rsqrtf
libc.src.__support.math.rsqrtf16
libc.src.__support.math.sin
+ libc.src.__support.math.sincos
)
diff --git a/libc/test/shared/shared_math_test.cpp b/libc/test/shared/shared_math_test.cpp
index 655d96692f1b8..b830c7e7e6991 100644
--- a/libc/test/shared/shared_math_test.cpp
+++ b/libc/test/shared/shared_math_test.cpp
@@ -87,6 +87,8 @@ TEST(LlvmLibcSharedMathTest, AllFloat) {
}
TEST(LlvmLibcSharedMathTest, AllDouble) {
+ double sin, cos;
+ LIBC_NAMESPACE::shared::sincos(0.0, &sin, &cos);
EXPECT_FP_EQ(0x1.921fb54442d18p+0, LIBC_NAMESPACE::shared::acos(0.0));
EXPECT_FP_EQ(0x0p+0, LIBC_NAMESPACE::shared::asin(0.0));
EXPECT_FP_EQ(0x0p+0, LIBC_NAMESPACE::shared::atan(0.0));
@@ -101,6 +103,8 @@ TEST(LlvmLibcSharedMathTest, AllDouble) {
EXPECT_FP_EQ(0x0p+0, LIBC_NAMESPACE::shared::fsqrt(0.0));
EXPECT_FP_EQ(0x0p+0, LIBC_NAMESPACE::shared::log(1.0));
EXPECT_FP_EQ(0.0, LIBC_NAMESPACE::shared::sin(0.0));
+ EXPECT_FP_EQ(1.0, cos);
+ EXPECT_FP_EQ(0.0, sin);
}
TEST(LlvmLibcSharedMathTest, AllLongDouble) {
>From 7ae2dd56bd19e5989f0b923d91dda0a25741b40f Mon Sep 17 00:00:00 2001
From: Ash <97464181+tnuha at users.noreply.github.com>
Date: Tue, 27 Jan 2026 03:11:01 +0000
Subject: [PATCH 09/13] Update libc/src/__support/math/sincos.h
Co-authored-by: Muhammad Bassiouni <60100307+bassiounix at users.noreply.github.com>
---
libc/src/__support/math/sincos.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/libc/src/__support/math/sincos.h b/libc/src/__support/math/sincos.h
index 677ebfc480e53..ecfea0c70c315 100644
--- a/libc/src/__support/math/sincos.h
+++ b/libc/src/__support/math/sincos.h
@@ -25,9 +25,9 @@
#include "src/__support/macros/properties/cpu_features.h" // LIBC_TARGET_CPU_HAS_FMA
#ifdef LIBC_TARGET_CPU_HAS_FMA_DOUBLE
-#include "src/__support/math/range_reduction_double_fma.h"
+#include "range_reduction_double_fma.h"
#else
-#include "src/__support/math/range_reduction_double_nofma.h"
+#include "range_reduction_double_nofma.h"
#endif // LIBC_TARGET_CPU_HAS_FMA_DOUBLE
namespace LIBC_NAMESPACE_DECL {
>From aead1f3fb4d876ba4aadc849ca4d0834ea7d108e Mon Sep 17 00:00:00 2001
From: Ash <97464181+tnuha at users.noreply.github.com>
Date: Tue, 27 Jan 2026 03:11:16 +0000
Subject: [PATCH 10/13] Update libc/src/__support/math/sincos.h
Co-authored-by: Muhammad Bassiouni <60100307+bassiounix at users.noreply.github.com>
---
libc/src/__support/math/sincos.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/libc/src/__support/math/sincos.h b/libc/src/__support/math/sincos.h
index ecfea0c70c315..9d7eb9fba194e 100644
--- a/libc/src/__support/math/sincos.h
+++ b/libc/src/__support/math/sincos.h
@@ -34,7 +34,7 @@ namespace LIBC_NAMESPACE_DECL {
namespace math {
-LIBC_INLINE static constexpr void sincos(double x, double *sin_x,
+LIBC_INLINE static void sincos(double x, double *sin_x,
double *cos_x) {
using DoubleDouble = fputil::DoubleDouble;
using Float128 = typename fputil::DyadicFloat<128>;
>From e55d1e2a101113454b47dcfce5ad49a04f40b042 Mon Sep 17 00:00:00 2001
From: ash <ashkernel02 at gmail.com>
Date: Mon, 26 Jan 2026 20:27:12 -0700
Subject: [PATCH 11/13] math dependencies
---
utils/bazel/llvm-project-overlay/libc/BUILD.bazel | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
index de7812639d793..4015604eae2d2 100644
--- a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
@@ -3417,7 +3417,9 @@ libc_support_library(
":__support_fputil_rounding_mode",
":__support_macros_optimization",
":__support_macros_properties_cpu_features",
- ":__support_macros_config"
+ ":__support_macros_config",
+ ":__support_sincos_eval",
+ ":range_reduction_double_common",
],
)
>From 3906a69213fc3f9046547535b064c4b433c7aa8f Mon Sep 17 00:00:00 2001
From: Ash <97464181+tnuha at users.noreply.github.com>
Date: Tue, 27 Jan 2026 05:08:45 +0000
Subject: [PATCH 12/13] Update
utils/bazel/llvm-project-overlay/libc/BUILD.bazel
Co-authored-by: Muhammad Bassiouni <60100307+bassiounix at users.noreply.github.com>
---
utils/bazel/llvm-project-overlay/libc/BUILD.bazel | 1 +
1 file changed, 1 insertion(+)
diff --git a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
index 22dc64000e0cc..61cc5a0c160ea 100644
--- a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
@@ -5193,6 +5193,7 @@ libc_math_function(
name = "sincos",
additional_deps = [
":__support_math_sincos",
+ ":errno",
],
)
>From 085441bd09fcde046742af6a2126d6643847f5e9 Mon Sep 17 00:00:00 2001
From: ash <ashkernel02 at gmail.com>
Date: Mon, 26 Jan 2026 22:12:03 -0700
Subject: [PATCH 13/13] support range reduction double common
---
utils/bazel/llvm-project-overlay/libc/BUILD.bazel | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
index 61cc5a0c160ea..dceac92bd3a0c 100644
--- a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
@@ -3467,7 +3467,7 @@ libc_support_library(
":__support_macros_properties_cpu_features",
":__support_macros_config",
":__support_sincos_eval",
- ":range_reduction_double_common",
+ ":__support_range_reduction_double_common",
],
)
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