[libc][math][c23] Add asinbf16 math function (#184170)

Co-authored-by: bassiounix <muhammad.m.bassiouni@gmail.com>

libc/config/baremetal/aarch64/entrypoints.txt

@@ -792,6 +792,7 @@ endif()
 list(APPEND TARGET_LIBM_ENTRYPOINTS
   # bfloat16 entrypoints
   libc.src.math.atanbf16
+  libc.src.math.asinbf16
   libc.src.math.bf16add
   libc.src.math.bf16addf
   libc.src.math.bf16addl

libc/config/baremetal/arm/entrypoints.txt

@@ -801,6 +801,7 @@ endif()
 list(APPEND TARGET_LIBM_ENTRYPOINTS
   # bfloat16 entrypoints
   libc.src.math.atanbf16
+  libc.src.math.asinbf16
   libc.src.math.bf16add
   libc.src.math.bf16addf
   libc.src.math.bf16addl

libc/config/baremetal/riscv/entrypoints.txt

@@ -798,6 +798,7 @@ endif()
 list(APPEND TARGET_LIBM_ENTRYPOINTS
   # bfloat16 entrypoints
   libc.src.math.atanbf16
+  libc.src.math.asinbf16
   libc.src.math.bf16add
   libc.src.math.bf16addf
   libc.src.math.bf16addl

libc/config/darwin/aarch64/entrypoints.txt

@@ -611,6 +611,7 @@ endif()
 list(APPEND TARGET_LIBM_ENTRYPOINTS
   # bfloat16 entrypoints
   libc.src.math.atanbf16
+  libc.src.math.asinbf16
   libc.src.math.bf16add
   libc.src.math.bf16addf
   libc.src.math.bf16addl

libc/config/darwin/x86_64/entrypoints.txt

@@ -235,6 +235,7 @@ set(TARGET_LIBM_ENTRYPOINTS
 list(APPEND TARGET_LIBM_ENTRYPOINTS
   # bfloat16 entrypoints
   libc.src.math.atanbf16
+  libc.src.math.asinbf16
   libc.src.math.bf16add
   libc.src.math.bf16addf
   libc.src.math.bf16addl

libc/config/gpu/amdgpu/entrypoints.txt

@@ -627,6 +627,7 @@ endif()
 list(APPEND TARGET_LIBM_ENTRYPOINTS
   # bfloat16 entrypoints
   libc.src.math.atanbf16
+  libc.src.math.asinbf16
   libc.src.math.bf16add
   libc.src.math.bf16addf
   libc.src.math.bf16addl

libc/config/gpu/nvptx/entrypoints.txt

@@ -629,6 +629,7 @@ endif()
 list(APPEND TARGET_LIBM_ENTRYPOINTS
   # bfloat16 entrypoints
   libc.src.math.atanbf16
+  libc.src.math.asinbf16
   libc.src.math.bf16add
   libc.src.math.bf16addf
   libc.src.math.bf16addl

libc/config/linux/aarch64/entrypoints.txt

@@ -874,6 +874,7 @@ endif()
 list(APPEND TARGET_LIBM_ENTRYPOINTS
   # bfloat16 entrypoints
   libc.src.math.atanbf16
+  libc.src.math.asinbf16
   libc.src.math.bf16add
   libc.src.math.bf16addf
   libc.src.math.bf16addl

libc/config/linux/arm/entrypoints.txt

@@ -477,6 +477,7 @@ set(TARGET_LIBM_ENTRYPOINTS
 list(APPEND TARGET_LIBM_ENTRYPOINTS
   # bfloat16 entrypoints
   libc.src.math.atanbf16
+  libc.src.math.asinbf16
   libc.src.math.bf16add
   libc.src.math.bf16addf
   libc.src.math.bf16addl

libc/config/linux/riscv/entrypoints.txt

@@ -895,6 +895,7 @@ endif()
 list(APPEND TARGET_LIBM_ENTRYPOINTS
   # bfloat16 entrypoints
   libc.src.math.atanbf16
+  libc.src.math.asinbf16
   libc.src.math.bf16add
   libc.src.math.bf16addf
   libc.src.math.bf16addl

libc/config/linux/x86_64/entrypoints.txt

@@ -950,6 +950,7 @@ endif()
 list(APPEND TARGET_LIBM_ENTRYPOINTS
   # bfloat16 entrypoints
   libc.src.math.atanbf16
+  libc.src.math.asinbf16
   libc.src.math.bf16add
   libc.src.math.bf16addf
   libc.src.math.bf16addl

libc/config/windows/entrypoints.txt

@@ -323,6 +323,7 @@ set(TARGET_LIBM_ENTRYPOINTS
 list(APPEND TARGET_LIBM_ENTRYPOINTS
   # bfloat16 entrypoints
   libc.src.math.atanbf16
+  libc.src.math.asinbf16
   libc.src.math.bf16add
   libc.src.math.bf16addf
   libc.src.math.bf16addl

libc/docs/headers/math/index.rst

@@ -265,7 +265,7 @@ Higher Math Functions
 +-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
 | acospi    |                  |                 |                        | |check|              |                        |                        | 7.12.4.8               | F.10.1.8                   |
 +-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
-| asin      | |check|          | |check|         |                        | |check|              |                        |                        | 7.12.4.2               | F.10.1.2                   |
+| asin      | |check|          | |check|         |                        | |check|              |                        | |check|                | 7.12.4.2               | F.10.1.2                   |
 +-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
 | asinh     | |check|          |                 |                        | |check|              |                        |                        | 7.12.5.2               | F.10.2.2                   |
 +-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+

libc/shared/math.h

@@ -19,6 +19,7 @@
 #include "math/acospif.h"
 #include "math/acospif16.h"
 #include "math/asin.h"
+#include "math/asinbf16.h"
 #include "math/asinf.h"
 #include "math/asinf16.h"
 #include "math/asinhf.h"

libc/shared/math/asinbf16.h

@@ -0,0 +1,23 @@
+//===-- Shared asinbf16 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_ASINBF16_H
+#define LLVM_LIBC_SHARED_MATH_ASINBF16_H
+
+#include "shared/libc_common.h"
+#include "src/__support/math/asinbf16.h"
+
+namespace LIBC_NAMESPACE_DECL {
+namespace shared {
+
+using math::asinbf16;
+
+} // namespace shared
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SHARED_MATH_ASINBF16_H

libc/src/__support/FPUtil/multiply_add.h

@@ -23,7 +23,7 @@ namespace fputil {
 // which uses FMA instructions to speed up if available.
 
 template <typename T>
-LIBC_INLINE cpp::enable_if_t<(sizeof(T) > sizeof(void *)), T>
+LIBC_INLINE constexpr cpp::enable_if_t<(sizeof(T) > sizeof(void *)), T>
 multiply_add(const T &x, const T &y, const T &z) {
   return x * y + z;
 }

libc/src/__support/FPUtil/sqrt.h

@@ -15,8 +15,9 @@
 #include "src/__support/FPUtil/generic/sqrt.h"
 
 // Generic instruction specializations with __builtin_elementwise_sqrt.
-#if defined(LIBC_TARGET_CPU_HAS_FPU_FLOAT) ||                                  \
-    defined(LIBC_TARGET_CPU_HAS_FPU_DOUBLE)
+#if !defined(LIBC_HAS_CONSTANT_EVALUATION) &&                                  \
+    (defined(LIBC_TARGET_CPU_HAS_FPU_FLOAT) ||                                 \
+     defined(LIBC_TARGET_CPU_HAS_FPU_DOUBLE))
 
 #if __has_builtin(__builtin_elementwise_sqrt)
 

libc/src/__support/math/CMakeLists.txt

@@ -321,7 +321,6 @@ add_header_library(
     libc.src.__support.FPUtil.sqrt
     libc.src.__support.macros.optimization
     libc.src.__support.FPUtil.bfloat16
-    
 )
 
 add_header_library(
@@ -381,6 +380,21 @@ add_header_library(
     libc.src.__support.macros.optimization
 )
 
+add_header_library(
+  asinbf16
+  HDRS
+    asinbf16.h
+  DEPENDS
+    .inv_trigf_utils
+    libc.src.__support.FPUtil.fenv_impl
+    libc.src.__support.FPUtil.fp_bits
+    libc.src.__support.FPUtil.bfloat16
+    libc.src.__support.FPUtil.cast
+    libc.src.__support.FPUtil.multiply_add
+    libc.src.__support.FPUtil.sqrt
+    libc.src.__support.macros.optimization
+)
+
 add_header_library(
   atanpif16
   HDRS

libc/src/__support/math/acoshf_utils.h

@@ -99,7 +99,7 @@ LIBC_INLINE LIBC_CONSTEXPR double log_eval(double x) {
   uint64_t x_m = (x_u & FPBits::FRACTION_MASK) | FPBits::one().uintval();
   double m = FPBits(x_m).get_val();
 
-  double dx;
+  double dx = 0.0;
 
   // Perform exact range reduction
 #ifdef LIBC_TARGET_CPU_HAS_FMA_DOUBLE

libc/src/__support/math/asinbf16.h

@@ -0,0 +1,95 @@
+//===-- Implementation header for asinbf16 ----------------------*- 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_ASINBF16_H
+#define LLVM_LIBC_SRC___SUPPORT_MATH_ASINBF16_H
+
+#include "inv_trigf_utils.h"
+#include "src/__support/FPUtil/FEnvImpl.h"
+#include "src/__support/FPUtil/FPBits.h"
+#include "src/__support/FPUtil/bfloat16.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"
+
+namespace LIBC_NAMESPACE_DECL {
+namespace math {
+
+LIBC_INLINE LIBC_CONSTEXPR bfloat16 asinbf16(bfloat16 x) {
+  // Generated by Sollya using the following command:
+  // > display = hexadecimal;
+  // > round(pi/2, SG, RN);
+  constexpr float PI_2 = 0x1.921fb6p0f;
+
+  using FPBits = fputil::FPBits<bfloat16>;
+  FPBits xbits(x);
+
+  uint16_t x_u = xbits.uintval();
+  uint16_t x_abs = x_u & 0x7fff;
+  float x_sign = (x_u >> 15) ? -1 : 1;
+  float xf = x;
+
+  float xf_abs = (xf < 0 ? -xf : xf);
+  float x_sq = xf_abs * xf_abs;
+
+  // Case 1: |x| <= 0.5
+  if (x_abs <= 0x3F00) { // x_abs <= 0.5
+    // |x| = {0}
+    if (LIBC_UNLIKELY(x_abs == 0))
+      return x; // with sign
+
+    if (LIBC_UNLIKELY(x_abs <= 0x3D00)) {
+      int rounding = fputil::quick_get_round();
+      if ((xbits.is_pos() && rounding == FE_UPWARD) ||
+          (xbits.is_neg() && rounding == FE_DOWNWARD)) {
+        return fputil::cast<bfloat16>(fputil::multiply_add(xf, 0x1.0p-9f, xf));
+      }
+      return x;
+    }
+
+    float xp = fputil::cast<float>(inv_trigf_utils_internal::asin_eval(x_sq));
+    float result = xf * (fputil::multiply_add<float>(x_sq, xp, 1.0f));
+    return fputil::cast<bfloat16>(result);
+  }
+
+  // Case 2: 0.5 <|x| <= 1
+  //  using reduction: asin(x) = pi/2 - 2*asin(sqrt((1-x)/2))
+  if (x_abs <= 0x3F80) { // x_abs <= 1
+    // |x| = {1}
+    if (LIBC_UNLIKELY(x_abs == 0x3F80)) {
+      return fputil::cast<bfloat16>(x_sign * PI_2);
+    }
+
+    float t = fputil::multiply_add<float>(xf_abs, -0.5f, 0.5f);
+    float t_sqrt = fputil::sqrt<float>(t);
+    float tp = fputil::cast<float>(inv_trigf_utils_internal::asin_eval(t));
+    float asin_sqrt_t = t_sqrt * (fputil::multiply_add<float>(t, tp, 1.0f));
+    float result = fputil::multiply_add<float>(-2.0f, asin_sqrt_t, PI_2);
+    return fputil::cast<bfloat16>(x_sign * result);
+  }
+
+  // Case 3: NaN and Inf
+  // NaN
+  if (xbits.is_nan()) {
+    if (xbits.is_signaling_nan()) {
+      fputil::raise_except_if_required(FE_INVALID);
+      return FPBits::quiet_nan().get_val();
+    }
+    return x; // quiet NaN
+  }
+  // |x|>1 & inf
+  fputil::raise_except_if_required(FE_INVALID);
+  fputil::set_errno_if_required(EDOM); // Domain is bounded
+  return FPBits::quiet_nan().get_val();
+}
+
+} // namespace math
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC___SUPPORT_MATH_ASINBF16_H

libc/src/__support/math/inv_trigf_utils.h

@@ -171,7 +171,7 @@ LIBC_INLINE_VAR constexpr double ASIN_COEFFS[12] = {
 };
 
 // Evaluate P(x^2) - 1, where P(x^2) ~ asin(x)/x
-LIBC_INLINE double asin_eval(double xsq) {
+LIBC_INLINE LIBC_CONSTEXPR double asin_eval(double xsq) {
   double x4 = xsq * xsq;
   double c0 = fputil::multiply_add(xsq, ASIN_COEFFS[1], ASIN_COEFFS[0]);
   double c1 = fputil::multiply_add(xsq, ASIN_COEFFS[3], ASIN_COEFFS[2]);

libc/src/math/CMakeLists.txt

@@ -52,6 +52,7 @@ add_math_entrypoint_object(acospif)
 add_math_entrypoint_object(acospif16)
  
 add_math_entrypoint_object(asin)
+add_math_entrypoint_object(asinbf16)
 add_math_entrypoint_object(asinf)
 add_math_entrypoint_object(asinf16)
 

libc/src/math/asinbf16.h

@@ -0,0 +1,21 @@
+//===-- Implementation header for asinbf16 ----------------------*- 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_ASINBF16_H
+#define LLVM_LIBC_SRC_MATH_ASINBF16_H
+
+#include "src/__support/macros/config.h"
+#include "src/__support/macros/properties/types.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+bfloat16 asinbf16(bfloat16 x);
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_MATH_ASINBF16_H

libc/src/math/generic/CMakeLists.txt

@@ -4098,6 +4098,16 @@ add_entrypoint_object(
     libc.src.__support.math.atanpif16
 )
 
+add_entrypoint_object(
+  asinbf16
+  SRCS
+    asinbf16.cpp
+  HDRS
+    ../asinbf16.h
+  DEPENDS
+    libc.src.__support.math.asinbf16
+)
+
 add_entrypoint_object(
   asinf
   SRCS

libc/src/math/generic/asinbf16.cpp

@@ -0,0 +1,18 @@
+//===-- Implementation for asinbf16(x) 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/asinbf16.h"
+#include "src/__support/math/asinbf16.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+LLVM_LIBC_FUNCTION(bfloat16, asinbf16, (bfloat16 x)) {
+  return math::asinbf16(x);
+}
+
+} // namespace LIBC_NAMESPACE_DECL

libc/test/shared/CMakeLists.txt

@@ -16,6 +16,7 @@ add_fp_unittest(
     libc.src.__support.math.acospif
     libc.src.__support.math.acospif16
     libc.src.__support.math.asin
+    libc.src.__support.math.asinbf16
     libc.src.__support.math.asinf
     libc.src.__support.math.asinf16
     libc.src.__support.math.asinhf
@@ -266,5 +267,12 @@ add_fp_unittest(
   SRCS
     shared_math_constexpr_test.cpp
   DEPENDS
-    .shared_math_test
+    libc.src.__support.math.asinbf16
+    libc.src.__support.math.ceil
+    libc.src.__support.math.ceilbf16
+    libc.src.__support.math.ceilf
+    libc.src.__support.math.ceilf128
+    libc.src.__support.math.ceilf16
+    libc.src.__support.math.ceill
+    libc.src.__support.math.log
 )

libc/test/shared/shared_math_constexpr_test.cpp

@@ -9,6 +9,7 @@
 #define LIBC_ENABLE_CONSTEXPR 1
 
 #include "shared/math.h"
+#include "test/UnitTest/Test.h"
 
 //===----------------------------------------------------------------------===//
 //                       Double Tests
@@ -58,4 +59,7 @@ static_assert(float128(0.0) == LIBC_NAMESPACE::shared::ceilf128(float128(0.0)));
 //                       BFloat16 Tests
 //===----------------------------------------------------------------------===//
 
+static_assert(bfloat16(0.0) == LIBC_NAMESPACE::shared::asinbf16(bfloat16(0.0)));
 static_assert(bfloat16(0.0) == LIBC_NAMESPACE::shared::ceilbf16(bfloat16(0.0)));
+
+TEST(LlvmLibcSharedMathTest, ConstantEvaluation) {}

libc/test/shared/shared_math_test.cpp

@@ -445,6 +445,13 @@ TEST(LlvmLibcSharedMathTest, AllFloat128) {
 TEST(LlvmLibcSharedMathTest, AllBFloat16) {
   using FPBits = LIBC_NAMESPACE::fputil::FPBits<bfloat16>;
   EXPECT_FP_EQ(bfloat16(0.0), LIBC_NAMESPACE::shared::atanbf16(bfloat16(0.0)));
+  EXPECT_FP_EQ(bfloat16(0.0), LIBC_NAMESPACE::shared::asinbf16(bfloat16(0.0)));
+  EXPECT_FP_EQ(bfloat16(5.0), LIBC_NAMESPACE::shared::bf16add(2.0, 3.0));
+  EXPECT_FP_EQ(bfloat16(2.0f), LIBC_NAMESPACE::shared::bf16divf(4.0f, 2.0f));
+  EXPECT_FP_EQ(bfloat16(2.0), LIBC_NAMESPACE::shared::bf16divl(6.0L, 3.0L));
+  EXPECT_FP_EQ(bfloat16(2.0), LIBC_NAMESPACE::shared::bf16div(4.0, 2.0));
+  EXPECT_FP_EQ(bfloat16(10.0),
+               LIBC_NAMESPACE::shared::bf16fmal(2.0L, 3.0L, 4.0L));
 
   bfloat16 canonicalizebf16_cx = bfloat16(0.0);
   bfloat16 canonicalizebf16_x = bfloat16(0.0);

libc/test/src/math/CMakeLists.txt

@@ -2512,6 +2512,19 @@ add_fp_unittest(
     libc.src.math.asin
 )
 
+add_fp_unittest(
+  asinbf16_test
+  NEED_MPFR
+  SUITE
+    libc-math-unittests
+  SRCS
+    asinbf16_test.cpp
+  DEPENDS
+    libc.src.math.asinbf16
+    libc.src.__support.FPUtil.fp_bits
+    libc.src.__support.FPUtil.bfloat16
+)
+
 add_fp_unittest(
   asinf16_test
   NEED_MPFR

libc/test/src/math/asinbf16_test.cpp

@@ -0,0 +1,43 @@
+//===-- Exhaustive test for asinbf16 --------------------------------------===//
+//
+// 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/bfloat16.h"
+#include "src/math/asinbf16.h"
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+#include "utils/MPFRWrapper/MPFRUtils.h"
+
+using LlvmLibcAsinBf16Test = LIBC_NAMESPACE::testing::FPTest<bfloat16>;
+
+namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
+
+// Range: [0, Inf]
+static constexpr uint16_t POS_START = 0x0000U;
+static constexpr uint16_t POS_STOP = 0x7f80U;
+
+// Range: [-Inf, 0]
+static constexpr uint16_t NEG_START = 0x8000U;
+static constexpr uint16_t NEG_STOP = 0xff80U;
+
+TEST_F(LlvmLibcAsinBf16Test, PositiveRange) {
+  for (uint16_t v = POS_START; v <= POS_STOP; ++v) {
+    bfloat16 x = FPBits(v).get_val();
+
+    EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Asin, x,
+                                   LIBC_NAMESPACE::asinbf16(x), 0.5);
+  }
+}
+
+TEST_F(LlvmLibcAsinBf16Test, NegativeRange) {
+  for (uint16_t v = NEG_START; v <= NEG_STOP; ++v) {
+    bfloat16 x = FPBits(v).get_val();
+
+    EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Asin, x,
+                                   LIBC_NAMESPACE::asinbf16(x), 0.5);
+  }
+}

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

@@ -4839,6 +4839,19 @@ add_fp_unittest(
     libc.src.math.asin
 )
 
+add_fp_unittest(
+  asinbf16_test
+  SUITE
+    libc-math-smoke-tests
+  SRCS
+    asinbf16_test.cpp
+  DEPENDS
+    libc.hdr.errno_macros
+    libc.src.math.asinbf16
+    libc.hdr.fenv_macros
+    libc.src.__support.FPUtil.bfloat16
+)
+
 add_fp_unittest(
   asinf16_test
   SUITE

libc/test/src/math/smoke/asinbf16_test.cpp

@@ -0,0 +1,41 @@
+//===-- Unittests for asinbf16 --------------------------------------------===//
+//
+//
+// 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 "hdr/errno_macros.h"
+#include "src/__support/FPUtil/bfloat16.h"
+#include "src/math/asinbf16.h"
+#include "test/UnitTest/FEnvSafeTest.h"
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+
+class LlvmLibcAsinBf16Test : public LIBC_NAMESPACE::testing::FEnvSafeTest {
+  DECLARE_SPECIAL_CONSTANTS(bfloat16)
+public:
+  void test_special_numbers() {
+    EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::asinbf16(aNaN));
+    EXPECT_MATH_ERRNO(0);
+
+    EXPECT_FP_EQ_WITH_EXCEPTION_ALL_ROUNDING(
+        aNaN, LIBC_NAMESPACE::asinbf16(sNaN), FE_INVALID);
+    EXPECT_MATH_ERRNO(0);
+
+    EXPECT_FP_EQ_ALL_ROUNDING(zero, LIBC_NAMESPACE::asinbf16(zero));
+    EXPECT_MATH_ERRNO(0);
+
+    EXPECT_FP_EQ_ALL_ROUNDING(neg_zero, LIBC_NAMESPACE::asinbf16(neg_zero));
+    EXPECT_MATH_ERRNO(0);
+
+    EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::asinbf16(inf));
+    EXPECT_MATH_ERRNO(EDOM);
+
+    EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::asinbf16(neg_inf));
+    EXPECT_MATH_ERRNO(EDOM);
+  }
+};
+TEST_F(LlvmLibcAsinBf16Test, SpecialNumbers) { test_special_numbers(); }

utils/bazel/llvm-project-overlay/libc/BUILD.bazel

@@ -3367,6 +3367,21 @@ libc_support_library(
     ],
 )
 
+libc_support_library(
+    name = "__support_math_asinbf16",
+    hdrs = ["src/__support/math/asinbf16.h"],
+    deps = [
+        ":__support_fputil_bfloat16",
+        ":__support_fputil_cast",
+        ":__support_fputil_fenv_impl",
+        ":__support_fputil_fp_bits",
+        ":__support_fputil_multiply_add",
+        ":__support_fputil_sqrt",
+        ":__support_macros_optimization",
+        ":__support_math_inv_trigf_utils",
+    ],
+)
+
 libc_support_library(
     name = "__support_math_asinf",
     hdrs = ["src/__support/math/asinf.h"],
@@ -6563,6 +6578,13 @@ libc_math_function(
     additional_deps = [":__support_math_asin"],
 )
 
+libc_math_function(
+    name = "asinbf16",
+    additional_deps = [
+        ":__support_math_asinbf16",
+    ],
+)
+
 libc_math_function(
     name = "asinf",
     additional_deps = [":__support_math_asinf"],