[libc-commits] [libc] [libc][math] Implement cbrtf function correctly rounded to all rounding modes. (PR #97936)
via libc-commits
libc-commits at lists.llvm.org
Sat Jul 6 21:36:39 PDT 2024
https://github.com/lntue updated https://github.com/llvm/llvm-project/pull/97936
>From 435f286882f19475b92b573e39352971be4aaa27 Mon Sep 17 00:00:00 2001
From: Tue Ly <lntue.h at gmail.com>
Date: Sun, 7 Jul 2024 04:01:46 +0000
Subject: [PATCH 1/2] [libc][math] Implement cbrtf function correctly rounded
to all rounding modes.
---
libc/config/darwin/arm/entrypoints.txt | 1 +
libc/config/gpu/entrypoints.txt | 1 +
libc/config/linux/aarch64/entrypoints.txt | 1 +
libc/config/linux/arm/entrypoints.txt | 1 +
libc/config/linux/riscv/entrypoints.txt | 1 +
libc/config/linux/x86_64/entrypoints.txt | 1 +
libc/config/windows/entrypoints.txt | 1 +
libc/docs/math/index.rst | 2 +-
libc/spec/stdc.td | 2 +
libc/src/__support/FPUtil/FEnvImpl.h | 6 +
libc/src/math/CMakeLists.txt | 2 +
libc/src/math/cbrtf.h | 18 ++
libc/src/math/generic/CMakeLists.txt | 16 ++
libc/src/math/generic/cbrtf.cpp | 157 ++++++++++++++++++
libc/test/src/math/CMakeLists.txt | 12 ++
libc/test/src/math/cbrtf_test.cpp | 42 +++++
libc/test/src/math/exhaustive/CMakeLists.txt | 16 ++
libc/test/src/math/exhaustive/cbrtf_test.cpp | 33 ++++
.../src/math/exhaustive/exhaustive_test.h | 15 +-
libc/test/src/math/smoke/CMakeLists.txt | 10 ++
libc/test/src/math/smoke/cbrtf_test.cpp | 33 ++++
libc/utils/MPFRWrapper/MPFRUtils.cpp | 8 +
libc/utils/MPFRWrapper/MPFRUtils.h | 1 +
23 files changed, 372 insertions(+), 8 deletions(-)
create mode 100644 libc/src/math/cbrtf.h
create mode 100644 libc/src/math/generic/cbrtf.cpp
create mode 100644 libc/test/src/math/cbrtf_test.cpp
create mode 100644 libc/test/src/math/exhaustive/cbrtf_test.cpp
create mode 100644 libc/test/src/math/smoke/cbrtf_test.cpp
diff --git a/libc/config/darwin/arm/entrypoints.txt b/libc/config/darwin/arm/entrypoints.txt
index 9eb7d8960c6e4..383118dc781e5 100644
--- a/libc/config/darwin/arm/entrypoints.txt
+++ b/libc/config/darwin/arm/entrypoints.txt
@@ -123,6 +123,7 @@ set(TARGET_LIBM_ENTRYPOINTS
libc.src.math.atan2f
libc.src.math.atanf
libc.src.math.atanhf
+ libc.src.math.cbrtf
libc.src.math.copysign
libc.src.math.copysignf
libc.src.math.copysignl
diff --git a/libc/config/gpu/entrypoints.txt b/libc/config/gpu/entrypoints.txt
index c8d68d61f3212..62f3f0df247cc 100644
--- a/libc/config/gpu/entrypoints.txt
+++ b/libc/config/gpu/entrypoints.txt
@@ -242,6 +242,7 @@ set(TARGET_LIBM_ENTRYPOINTS
libc.src.math.atanf
libc.src.math.atanh
libc.src.math.atanhf
+ libc.src.math.cbrtf
libc.src.math.ceil
libc.src.math.ceilf
libc.src.math.copysign
diff --git a/libc/config/linux/aarch64/entrypoints.txt b/libc/config/linux/aarch64/entrypoints.txt
index 6c67e4bbadee7..2e4ac7b98c8ec 100644
--- a/libc/config/linux/aarch64/entrypoints.txt
+++ b/libc/config/linux/aarch64/entrypoints.txt
@@ -343,6 +343,7 @@ set(TARGET_LIBM_ENTRYPOINTS
libc.src.math.atan2f
libc.src.math.atanf
libc.src.math.atanhf
+ libc.src.math.cbrtf
libc.src.math.ceil
libc.src.math.ceilf
libc.src.math.ceill
diff --git a/libc/config/linux/arm/entrypoints.txt b/libc/config/linux/arm/entrypoints.txt
index a24514e29334d..b0ee0e989b5ed 100644
--- a/libc/config/linux/arm/entrypoints.txt
+++ b/libc/config/linux/arm/entrypoints.txt
@@ -216,6 +216,7 @@ set(TARGET_LIBM_ENTRYPOINTS
libc.src.math.atan2f
libc.src.math.atanf
libc.src.math.atanhf
+ libc.src.math.cbrtf
libc.src.math.ceil
libc.src.math.ceilf
libc.src.math.ceill
diff --git a/libc/config/linux/riscv/entrypoints.txt b/libc/config/linux/riscv/entrypoints.txt
index 2b7e3d0256fc3..37f5764547401 100644
--- a/libc/config/linux/riscv/entrypoints.txt
+++ b/libc/config/linux/riscv/entrypoints.txt
@@ -345,6 +345,7 @@ set(TARGET_LIBM_ENTRYPOINTS
libc.src.math.atan2f
libc.src.math.atanf
libc.src.math.atanhf
+ libc.src.math.cbrtf
libc.src.math.ceil
libc.src.math.ceilf
libc.src.math.ceill
diff --git a/libc/config/linux/x86_64/entrypoints.txt b/libc/config/linux/x86_64/entrypoints.txt
index 2ca8f00d2de50..57a6a1f53375a 100644
--- a/libc/config/linux/x86_64/entrypoints.txt
+++ b/libc/config/linux/x86_64/entrypoints.txt
@@ -368,6 +368,7 @@ set(TARGET_LIBM_ENTRYPOINTS
libc.src.math.canonicalize
libc.src.math.canonicalizef
libc.src.math.canonicalizel
+ libc.src.math.cbrtf
libc.src.math.ceil
libc.src.math.ceilf
libc.src.math.ceill
diff --git a/libc/config/windows/entrypoints.txt b/libc/config/windows/entrypoints.txt
index b33d572cf999a..499c6bfe3a229 100644
--- a/libc/config/windows/entrypoints.txt
+++ b/libc/config/windows/entrypoints.txt
@@ -121,6 +121,7 @@ set(TARGET_LIBM_ENTRYPOINTS
libc.src.math.atan2f
libc.src.math.atanf
libc.src.math.atanhf
+ libc.src.math.cbrtf
libc.src.math.copysign
libc.src.math.copysignf
libc.src.math.copysignl
diff --git a/libc/docs/math/index.rst b/libc/docs/math/index.rst
index 422acfcdd4cec..7914a3d7e6d1a 100644
--- a/libc/docs/math/index.rst
+++ b/libc/docs/math/index.rst
@@ -266,7 +266,7 @@ Higher Math Functions
+-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
| atanpi | | | | | | 7.12.4.10 | F.10.1.10 |
+-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
-| cbrt | | | | | | 7.12.7.1 | F.10.4.1 |
+| cbrt | |check| | | | | | 7.12.7.1 | F.10.4.1 |
+-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
| compoundn | | | | | | 7.12.7.2 | F.10.4.2 |
+-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
diff --git a/libc/spec/stdc.td b/libc/spec/stdc.td
index feaa3fbfa66aa..aa56152aee141 100644
--- a/libc/spec/stdc.td
+++ b/libc/spec/stdc.td
@@ -382,6 +382,8 @@ def StdC : StandardSpec<"stdc"> {
],
[], // Enumerations
[
+ FunctionSpec<"cbrtf", RetValSpec<FloatType>, [ArgSpec<FloatType>]>,
+
FunctionSpec<"copysign", RetValSpec<DoubleType>, [ArgSpec<DoubleType>, ArgSpec<DoubleType>]>,
FunctionSpec<"copysignf", RetValSpec<FloatType>, [ArgSpec<FloatType>, ArgSpec<FloatType>]>,
FunctionSpec<"copysignl", RetValSpec<LongDoubleType>, [ArgSpec<LongDoubleType>, ArgSpec<LongDoubleType>]>,
diff --git a/libc/src/__support/FPUtil/FEnvImpl.h b/libc/src/__support/FPUtil/FEnvImpl.h
index 13e668becc651..1674dd0358e88 100644
--- a/libc/src/__support/FPUtil/FEnvImpl.h
+++ b/libc/src/__support/FPUtil/FEnvImpl.h
@@ -67,6 +67,12 @@ LIBC_INLINE int set_env(const fenv_t *) { return 0; }
namespace LIBC_NAMESPACE::fputil {
+LIBC_INLINE int clear_except_if_required(int excepts) {
+ if (math_errhandling & MATH_ERREXCEPT)
+ return clear_except(excepts);
+ return 0;
+}
+
LIBC_INLINE int set_except_if_required(int excepts) {
if (math_errhandling & MATH_ERREXCEPT)
return set_except(excepts);
diff --git a/libc/src/math/CMakeLists.txt b/libc/src/math/CMakeLists.txt
index e21011f37b53c..74c2e4efda617 100644
--- a/libc/src/math/CMakeLists.txt
+++ b/libc/src/math/CMakeLists.txt
@@ -65,6 +65,8 @@ add_math_entrypoint_object(canonicalizel)
add_math_entrypoint_object(canonicalizef16)
add_math_entrypoint_object(canonicalizef128)
+add_math_entrypoint_object(cbrtf)
+
add_math_entrypoint_object(ceil)
add_math_entrypoint_object(ceilf)
add_math_entrypoint_object(ceill)
diff --git a/libc/src/math/cbrtf.h b/libc/src/math/cbrtf.h
new file mode 100644
index 0000000000000..74744594f2986
--- /dev/null
+++ b/libc/src/math/cbrtf.h
@@ -0,0 +1,18 @@
+//===-- Implementation header for cbrtf -------------------------*- 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_CBRTF_H
+#define LLVM_LIBC_SRC_MATH_CBRTF_H
+
+namespace LIBC_NAMESPACE {
+
+float cbrtf(float x);
+
+} // namespace LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SRC_MATH_CBRTF_H
diff --git a/libc/src/math/generic/CMakeLists.txt b/libc/src/math/generic/CMakeLists.txt
index fc7d6996af1e6..e2bbdcfe5a15b 100644
--- a/libc/src/math/generic/CMakeLists.txt
+++ b/libc/src/math/generic/CMakeLists.txt
@@ -4092,3 +4092,19 @@ add_entrypoint_object(
COMPILE_OPTIONS
-O3
)
+
+add_entrypoint_object(
+ cbrtf
+ SRCS
+ cbrtf.cpp
+ HDRS
+ ../cbrtf.h
+ COMPILE_OPTIONS
+ -O3
+ DEPENDS
+ libc.hdr.fenv_macros
+ libc.src.__support.FPUtil.fenv_impl
+ libc.src.__support.FPUtil.fp_bits
+ libc.src.__support.FPUtil.multiply_add
+ libc.src.__support.macros.optimization
+)
diff --git a/libc/src/math/generic/cbrtf.cpp b/libc/src/math/generic/cbrtf.cpp
new file mode 100644
index 0000000000000..a1eb58d463a06
--- /dev/null
+++ b/libc/src/math/generic/cbrtf.cpp
@@ -0,0 +1,157 @@
+//===-- Implementation of cbrtf 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/cbrtf.h"
+#include "hdr/fenv_macros.h"
+#include "src/__support/FPUtil/FEnvImpl.h"
+#include "src/__support/FPUtil/FPBits.h"
+#include "src/__support/FPUtil/multiply_add.h"
+#include "src/__support/common.h"
+#include "src/__support/macros/optimization.h" // LIBC_UNLIKELY
+
+namespace LIBC_NAMESPACE {
+
+namespace {
+
+// Look up table for 2^(i/3) for i = 0, 1, 2.
+constexpr double CBRT2[3] = {1.0, 0x1.428a2f98d728bp0, 0x1.965fea53d6e3dp0};
+
+// Degree-7 polynomials approximation of ((1 + x)^(1/3) - 1)/x for 0 <= x <= 1
+// generated by Sollya with:
+// > for i from 0 to 15 do {
+// P = fpminimax((1 + x)^(1/3) - 1)/x, 6, [|D...|], [i/16, (i + 1)/16]);
+// print("{", coeff(P, 0), ",", coeff(P, 1), ",", coeff(P, 2), ",",
+// coeff(P, 3), ",", coeff(P, 4), ",", coeff(P, 5), ",",
+// coeff(P, 6), "},");
+// };
+// Then (1 + x)^(1/3) ~ 1 + x * P(x).
+constexpr double COEFFS[16][7] = {
+ {0x1.55555555554ebp-2, -0x1.c71c71c678c0cp-4, 0x1.f9add2776de81p-5,
+ -0x1.511e10aa964a7p-5, 0x1.ee44165937fa2p-6, -0x1.7c5c9e059345dp-6,
+ 0x1.047f75e0aff14p-6},
+ {0x1.5555554d1149ap-2, -0x1.c71c676fcb5bp-4, 0x1.f9ab127dc57ebp-5,
+ -0x1.50ea8fd1d4c15p-5, 0x1.e9d68f28ced43p-6, -0x1.60e0e1e661311p-6,
+ 0x1.716eca1d6e3bcp-7},
+ {0x1.5555546377d45p-2, -0x1.c71bc1c6d49d2p-4, 0x1.f9924cc0ed24dp-5,
+ -0x1.4fea3beb53b3bp-5, 0x1.de028a9a07b1bp-6, -0x1.3b090d2233524p-6,
+ 0x1.0aeca34893785p-7},
+ {0x1.55554dce9f649p-2, -0x1.c7188b34b98f8p-4, 0x1.f93e1af34af49p-5,
+ -0x1.4d9a06be75c63p-5, 0x1.cb943f4f68992p-6, -0x1.139a685a5e3c4p-6,
+ 0x1.88410674c6a5dp-8},
+ {0x1.5555347d211c3p-2, -0x1.c70f2a4b1a5fap-4, 0x1.f88420e8602c3p-5,
+ -0x1.49becfa4ed3ep-5, 0x1.b475cd9013162p-6, -0x1.dcfee1dd2f8efp-7,
+ 0x1.249bb51a1c498p-8},
+ {0x1.5554f01b33dbap-2, -0x1.c6facb929dbf1p-4, 0x1.f73fb7861252ep-5,
+ -0x1.4459a4a0071fap-5, 0x1.9a8df2b504fc2p-6, -0x1.9a7ce3006d06ep-7,
+ 0x1.ba9230918fa2ep-9},
+ {0x1.55545c695db5fp-2, -0x1.c6d6089f20275p-4, 0x1.f556e0ea80efp-5,
+ -0x1.3d91372d083f4p-5, 0x1.7f66cff331f4p-6, -0x1.606a562491737p-7,
+ 0x1.52e3e17c71069p-9},
+ {0x1.55534a879232ap-2, -0x1.c69b836998b84p-4, 0x1.f2bb26dac0e4cp-5,
+ -0x1.359eed43716d7p-5, 0x1.64218cd824fbcp-6, -0x1.2e703e2e091e8p-7,
+ 0x1.0677d9af6aad4p-9},
+ {0x1.5551836bb5494p-2, -0x1.c64658c15353bp-4, 0x1.ef68517451a6ep-5,
+ -0x1.2cc20a980dceep-5, 0x1.49843e0fad93ap-6, -0x1.03c59ccb68e54p-7,
+ 0x1.9ad325dc7adcbp-10},
+ {0x1.554ecacb0d035p-2, -0x1.c5d2664026ffcp-4, 0x1.eb624796ba809p-5,
+ -0x1.233803d19a535p-5, 0x1.300decb1c3c28p-6, -0x1.befe18031ec3dp-8,
+ 0x1.449f5ee175c69p-10},
+ {0x1.554ae1f5ae815p-2, -0x1.c53c6b14ff6b2p-4, 0x1.e6b2d5127bb5bp-5,
+ -0x1.19387336788a3p-5, 0x1.180955a6ab255p-6, -0x1.81696703ba369p-8,
+ 0x1.02cb36389bd79p-10},
+ {0x1.55458a59f356ep-2, -0x1.c4820dd631ae9p-4, 0x1.e167af818bd15p-5,
+ -0x1.0ef35f6f72e52p-5, 0x1.019c33b65e4ebp-6, -0x1.4d25bdd52d3a5p-8,
+ 0x1.a008ae91f5936p-11},
+ {0x1.553e878eafee1p-2, -0x1.c3a1d0b2a3db2p-4, 0x1.db90d8ed9f89bp-5,
+ -0x1.0490e20f1ae91p-5, 0x1.d9a5d1fc42fe3p-7, -0x1.20bf8227c2abfp-8,
+ 0x1.50f8174cdb6e9p-11},
+ {0x1.5535a0dedf1b1p-2, -0x1.c29afb8bd01a1p-4, 0x1.d53f6371c1e27p-5,
+ -0x1.f463209b433e2p-6, 0x1.b35222a17e44p-7, -0x1.f5efbf505e133p-9,
+ 0x1.12e0e94e8586dp-11},
+ {0x1.552aa25e57bfdp-2, -0x1.c16d811e4acadp-4, 0x1.ce8489b47aa51p-5,
+ -0x1.dfde7ff758ea8p-6, 0x1.901f43aac38c8p-7, -0x1.b581d07df5ad5p-9,
+ 0x1.c3726535f1fc6p-12},
+ {0x1.551d5d9b204d3p-2, -0x1.c019e328f8db1p-4, 0x1.c7710f44fc3cep-5,
+ -0x1.cbbbe25ea8ba4p-6, 0x1.6fe270088623dp-7, -0x1.7e6fc79733761p-9,
+ 0x1.75077abf18d84p-12},
+};
+
+} // anonymous namespace
+
+LLVM_LIBC_FUNCTION(float, cbrtf, (float x)) {
+ using FloatBits = typename fputil::FPBits<float>;
+ using DoubleBits = typename fputil::FPBits<double>;
+
+ FloatBits x_bits(x);
+
+ uint32_t x_abs = x_bits.uintval() & 0x7fff'ffff;
+ uint32_t sign_bit = (x_bits.uintval() >> 31) << DoubleBits::EXP_LEN;
+
+ if (LIBC_UNLIKELY(x_abs == 0 || x_abs >= 0x7f80'0000)) {
+ // x is 0, Inf, or NaN.
+ return x;
+ }
+
+ double xd = static_cast<double>(x);
+ DoubleBits xd_bits(xd);
+
+ // When using biased exponent of x in double precision,
+ // x_e = real_exponent_of_x + 1023
+ // Then:
+ // x_e / 3 = real_exponent_of_x / 3 + 1023/3
+ // = real_exponent_of_x / 3 + 341
+ // So to make it the correct biased exponent of x^(1/3), we add
+ // 1023 - 341 = 682
+ // to the quotient x_e / 3.
+ unsigned x_e = static_cast<unsigned>(xd_bits.get_biased_exponent());
+ unsigned out_e = (x_e / 3 + 682) | sign_bit;
+ unsigned shift_e = x_e % 3;
+
+ // Set x_m = 2^(x_e % 3) * (1.mantissa)
+ uint64_t x_m = xd_bits.get_mantissa();
+ // Use the leading 4 bits for look up table
+ unsigned idx = static_cast<unsigned>(x_m >> (DoubleBits::FRACTION_LEN - 4));
+
+ x_m |= static_cast<uint64_t>(DoubleBits::EXP_BIAS)
+ << DoubleBits::FRACTION_LEN;
+
+ double x_reduced = DoubleBits(x_m).get_val();
+ double dx = x_reduced - 1.0;
+
+ double dx_sq = dx * dx;
+ double c0 = fputil::multiply_add(dx, COEFFS[idx][0], 1.0);
+ double c1 = fputil::multiply_add(dx, COEFFS[idx][2], COEFFS[idx][1]);
+ double c2 = fputil::multiply_add(dx, COEFFS[idx][4], COEFFS[idx][3]);
+ double c3 = fputil::multiply_add(dx, COEFFS[idx][6], COEFFS[idx][5]);
+
+ double dx_4 = dx_sq * dx_sq;
+ double p0 = fputil::multiply_add(dx_sq, c1, c0);
+ double p1 = fputil::multiply_add(dx_sq, c3, c2);
+
+ double r = fputil::multiply_add(dx_4, p1, p0) * CBRT2[shift_e];
+
+ uint64_t r_m = DoubleBits(r).get_mantissa();
+ // Check if the output is exact. To be exact, the smallest 1-bit of the
+ // output has to be at least 2^-7 or higher. So we check the lowest 44 bits
+ // to see if they are within 2^(-52 + 3) errors from all zeros, then the
+ // result cube root is exact.
+ if (LIBC_UNLIKELY(((r_m + 8) & 0xfffffffffff) <= 16)) {
+ if ((r_m & 0xfffffffffff) <= 8)
+ r_m &= 0xffff'ffff'ffff'ffe0;
+ else
+ r_m = (r_m & 0xffff'ffff'ffff'ffe0) + 0x20;
+ fputil::clear_except_if_required(FE_INEXACT);
+ }
+ // Adjust exponent and sign.
+ uint64_t r_bits =
+ r_m | (static_cast<uint64_t>(out_e) << DoubleBits::FRACTION_LEN);
+
+ return static_cast<float>(DoubleBits(r_bits).get_val());
+}
+
+} // namespace LIBC_NAMESPACE
diff --git a/libc/test/src/math/CMakeLists.txt b/libc/test/src/math/CMakeLists.txt
index 35ca97b5de8af..0dc7ae6aae2df 100644
--- a/libc/test/src/math/CMakeLists.txt
+++ b/libc/test/src/math/CMakeLists.txt
@@ -2213,6 +2213,18 @@ add_fp_unittest(
libc.src.math.f16sqrtl
)
+add_fp_unittest(
+ cbrtf_test
+ NEED_MPFR
+ SUITE
+ libc-math-unittests
+ SRCS
+ cbrtf_test.cpp
+ DEPENDS
+ libc.src.math.cbrtf
+ libc.src.__support.FPUtil.fp_bits
+)
+
add_subdirectory(generic)
add_subdirectory(smoke)
diff --git a/libc/test/src/math/cbrtf_test.cpp b/libc/test/src/math/cbrtf_test.cpp
new file mode 100644
index 0000000000000..1d7d2189d5268
--- /dev/null
+++ b/libc/test/src/math/cbrtf_test.cpp
@@ -0,0 +1,42 @@
+//===-- Unittests for cbrtf -----------------------------------------------===//
+//
+// 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/math_macros.h"
+#include "src/__support/FPUtil/FPBits.h"
+#include "src/math/cbrtf.h"
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+#include "utils/MPFRWrapper/MPFRUtils.h"
+
+using LlvmLibcCbrtfTest = LIBC_NAMESPACE::testing::FPTest<float>;
+
+namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
+
+TEST_F(LlvmLibcCbrtfTest, InFloatRange) {
+ constexpr uint32_t COUNT = 100'000;
+ const uint32_t STEP = FPBits(inf).uintval() / COUNT;
+ for (uint32_t i = 0, v = 0; i <= COUNT; ++i, v += STEP) {
+ float x = FPBits(v).get_val();
+ EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Cbrt, x,
+ LIBC_NAMESPACE::cbrtf(x), 0.5);
+ EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Cbrt, -x,
+ LIBC_NAMESPACE::cbrtf(-x), 0.5);
+ }
+}
+
+TEST_F(LlvmLibcCbrtfTest, SpecialValues) {
+ constexpr float INPUTS[] = {
+ 0x1.60451p2f, 0x1.31304cp1f, 0x1.d17cp2f, 0x1.bp-143f, 0x1.338cp2f,
+ };
+ for (float v : INPUTS) {
+ float x = FPBits(v).get_val();
+ mpfr::ForceRoundingMode r(mpfr::RoundingMode::Upward);
+ EXPECT_MPFR_MATCH(mpfr::Operation::Cbrt, x, LIBC_NAMESPACE::cbrtf(x), 0.5,
+ mpfr::RoundingMode::Upward);
+ }
+}
diff --git a/libc/test/src/math/exhaustive/CMakeLists.txt b/libc/test/src/math/exhaustive/CMakeLists.txt
index c5f75b51cbd9f..6c10ea422109e 100644
--- a/libc/test/src/math/exhaustive/CMakeLists.txt
+++ b/libc/test/src/math/exhaustive/CMakeLists.txt
@@ -486,3 +486,19 @@ add_fp_unittest(
LINK_LIBRARIES
-lpthread
)
+
+add_fp_unittest(
+ cbrtf_test
+ NO_RUN_POSTBUILD
+ NEED_MPFR
+ SUITE
+ libc_math_exhaustive_tests
+ SRCS
+ cbrtf_test.cpp
+ DEPENDS
+ .exhaustive_test
+ libc.src.math.cbrtf
+ libc.src.__support.FPUtil.fp_bits
+ LINK_LIBRARIES
+ -lpthread
+)
diff --git a/libc/test/src/math/exhaustive/cbrtf_test.cpp b/libc/test/src/math/exhaustive/cbrtf_test.cpp
new file mode 100644
index 0000000000000..e4511e1f7ee1b
--- /dev/null
+++ b/libc/test/src/math/exhaustive/cbrtf_test.cpp
@@ -0,0 +1,33 @@
+//===-- Exhaustive test for cbrtf -----------------------------------------===//
+//
+// 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 "exhaustive_test.h"
+#include "src/math/cbrtf.h"
+#include "utils/MPFRWrapper/MPFRUtils.h"
+
+namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
+
+using LlvmLibcCbrtfExhaustiveTest =
+ LlvmLibcUnaryOpExhaustiveMathTest<float, mpfr::Operation::Cbrt,
+ LIBC_NAMESPACE::cbrtf>;
+
+// Range: [0, Inf];
+static constexpr uint32_t POS_START = 0x0000'0000U;
+static constexpr uint32_t POS_STOP = 0x7f80'0000U;
+
+TEST_F(LlvmLibcCbrtfExhaustiveTest, PostiveRange) {
+ test_full_range_all_roundings(POS_START, POS_STOP);
+}
+
+// Range: [-Inf, 0];
+static constexpr uint32_t NEG_START = 0x8000'0000U;
+static constexpr uint32_t NEG_STOP = 0xff80'0000U;
+
+TEST_F(LlvmLibcCbrtfExhaustiveTest, NegativeRange) {
+ test_full_range_all_roundings(NEG_START, NEG_STOP);
+}
diff --git a/libc/test/src/math/exhaustive/exhaustive_test.h b/libc/test/src/math/exhaustive/exhaustive_test.h
index 6f0c78ebefa47..94489d2e55daa 100644
--- a/libc/test/src/math/exhaustive/exhaustive_test.h
+++ b/libc/test/src/math/exhaustive/exhaustive_test.h
@@ -61,9 +61,9 @@ struct UnaryOpChecker : public virtual LIBC_NAMESPACE::testing::Test {
TEST_MPFR_MATCH_ROUNDING_SILENTLY(Op, x, Func(x), 0.5, rounding);
failed += (!correct);
// Uncomment to print out failed values.
- // if (!correct) {
- // EXPECT_MPFR_MATCH_ROUNDING(Op, x, Func(x), 0.5, rounding);
- // }
+ if (!correct) {
+ EXPECT_MPFR_MATCH_ROUNDING(Op, x, Func(x), 0.5, rounding);
+ }
} while (bits++ < stop);
return failed;
}
@@ -97,9 +97,9 @@ struct BinaryOpChecker : public virtual LIBC_NAMESPACE::testing::Test {
0.5, rounding);
failed += (!correct);
// Uncomment to print out failed values.
- // if (!correct) {
- // EXPECT_MPFR_MATCH_ROUNDING(Op, input, Func(x, y), 0.5, rounding);
- // }
+ if (!correct) {
+ EXPECT_MPFR_MATCH_ROUNDING(Op, input, Func(x, y), 0.5, rounding);
+ }
} while (ybits++ < y_stop);
} while (xbits++ < x_stop);
return failed;
@@ -187,7 +187,8 @@ struct LlvmLibcExhaustiveMathTest
std::stringstream msg;
msg << "Test failed for " << std::dec << failed_in_range
<< " inputs in range: ";
- explain_failed_range(msg, start, stop, extra_range_bounds...);
+ explain_failed_range(msg, range_begin, range_end,
+ extra_range_bounds...);
msg << "\n";
std::cerr << msg.str() << std::flush;
diff --git a/libc/test/src/math/smoke/CMakeLists.txt b/libc/test/src/math/smoke/CMakeLists.txt
index b72d4b30787a0..7f1bc0c204c68 100644
--- a/libc/test/src/math/smoke/CMakeLists.txt
+++ b/libc/test/src/math/smoke/CMakeLists.txt
@@ -3961,3 +3961,13 @@ add_fp_unittest(
DEPENDS
libc.src.math.tan
)
+
+add_fp_unittest(
+ cbrtf_test
+ SUITE
+ libc-math-smoke-tests
+ SRCS
+ cbrtf_test.cpp
+ DEPENDS
+ libc.src.math.cbrtf
+)
diff --git a/libc/test/src/math/smoke/cbrtf_test.cpp b/libc/test/src/math/smoke/cbrtf_test.cpp
new file mode 100644
index 0000000000000..5d75cd0075187
--- /dev/null
+++ b/libc/test/src/math/smoke/cbrtf_test.cpp
@@ -0,0 +1,33 @@
+//===-- Unittests for cbrtf -----------------------------------------------===//
+//
+// 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/cbrtf.h"
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+
+using LlvmLibcCbrtfTest = LIBC_NAMESPACE::testing::FPTest<float>;
+
+using LIBC_NAMESPACE::testing::tlog;
+
+TEST_F(LlvmLibcCbrtfTest, SpecialNumbers) {
+ // EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::cbrtf(aNaN));
+ // EXPECT_FP_EQ_ALL_ROUNDING(inf, LIBC_NAMESPACE::cbrtf(inf));
+ // EXPECT_FP_EQ_ALL_ROUNDING(neg_inf, LIBC_NAMESPACE::cbrtf(neg_inf));
+ // EXPECT_FP_EQ_ALL_ROUNDING(zero, LIBC_NAMESPACE::cbrtf(zero));
+ // EXPECT_FP_EQ_ALL_ROUNDING(neg_zero, LIBC_NAMESPACE::cbrtf(neg_zero));
+ // EXPECT_FP_EQ_ALL_ROUNDING(1.0f, LIBC_NAMESPACE::cbrtf(1.0f));
+ // EXPECT_FP_EQ_ALL_ROUNDING(-1.0f, LIBC_NAMESPACE::cbrtf(-1.0f));
+ // EXPECT_FP_EQ_ALL_ROUNDING(2.0f, LIBC_NAMESPACE::cbrtf(8.0f));
+ // EXPECT_FP_EQ_ALL_ROUNDING(-2.0f, LIBC_NAMESPACE::cbrtf(-8.0f));
+ EXPECT_FP_EQ_ALL_ROUNDING(3.0f, LIBC_NAMESPACE::cbrtf(27.0f));
+ // EXPECT_FP_EQ_ALL_ROUNDING(-3.0f, LIBC_NAMESPACE::cbrtf(-27.0f));
+ // EXPECT_FP_EQ_ALL_ROUNDING(5.0f, LIBC_NAMESPACE::cbrtf(125.0f));
+ // EXPECT_FP_EQ_ALL_ROUNDING(-5.0f, LIBC_NAMESPACE::cbrtf(-125.0f));
+ // EXPECT_FP_EQ_ALL_ROUNDING(0x1.0p42f, LIBC_NAMESPACE::cbrtf(0x1.0p126f));
+ // EXPECT_FP_EQ_ALL_ROUNDING(-0x1.0p42f, LIBC_NAMESPACE::cbrtf(-0x1.0p126f));
+}
diff --git a/libc/utils/MPFRWrapper/MPFRUtils.cpp b/libc/utils/MPFRWrapper/MPFRUtils.cpp
index 6548fc36cb6b4..99a240e555af2 100644
--- a/libc/utils/MPFRWrapper/MPFRUtils.cpp
+++ b/libc/utils/MPFRWrapper/MPFRUtils.cpp
@@ -221,6 +221,12 @@ class MPFRNumber {
return result;
}
+ MPFRNumber cbrt() const {
+ MPFRNumber result(*this);
+ mpfr_cbrt(result.value, value, mpfr_rounding);
+ return result;
+ }
+
MPFRNumber ceil() const {
MPFRNumber result(*this);
mpfr_ceil(result.value, value);
@@ -702,6 +708,8 @@ unary_operation(Operation op, InputType input, unsigned int precision,
return mpfrInput.atan();
case Operation::Atanh:
return mpfrInput.atanh();
+ case Operation::Cbrt:
+ return mpfrInput.cbrt();
case Operation::Ceil:
return mpfrInput.ceil();
case Operation::Cos:
diff --git a/libc/utils/MPFRWrapper/MPFRUtils.h b/libc/utils/MPFRWrapper/MPFRUtils.h
index 002dc919396e7..fd0d72472bf7e 100644
--- a/libc/utils/MPFRWrapper/MPFRUtils.h
+++ b/libc/utils/MPFRWrapper/MPFRUtils.h
@@ -31,6 +31,7 @@ enum class Operation : int {
Asinh,
Atan,
Atanh,
+ Cbrt,
Ceil,
Cos,
Cosh,
>From c50769060662832c2c6d034e43d9f4f0dfa22e27 Mon Sep 17 00:00:00 2001
From: Tue Ly <lntue.h at gmail.com>
Date: Sun, 7 Jul 2024 04:35:59 +0000
Subject: [PATCH 2/2] Fix smoke test and missing FMA flag from
FPUtil.multiply_add target.
---
libc/src/__support/FPUtil/CMakeLists.txt | 2 ++
libc/test/src/math/smoke/cbrtf_test.cpp | 28 ++++++++++++------------
2 files changed, 16 insertions(+), 14 deletions(-)
diff --git a/libc/src/__support/FPUtil/CMakeLists.txt b/libc/src/__support/FPUtil/CMakeLists.txt
index 84c5f802710c4..793d3a121c742 100644
--- a/libc/src/__support/FPUtil/CMakeLists.txt
+++ b/libc/src/__support/FPUtil/CMakeLists.txt
@@ -155,6 +155,8 @@ add_header_library(
multiply_add.h
DEPENDS
libc.src.__support.common
+ FLAGS
+ FMA_OPT
)
add_header_library(
diff --git a/libc/test/src/math/smoke/cbrtf_test.cpp b/libc/test/src/math/smoke/cbrtf_test.cpp
index 5d75cd0075187..a68e57744bd0e 100644
--- a/libc/test/src/math/smoke/cbrtf_test.cpp
+++ b/libc/test/src/math/smoke/cbrtf_test.cpp
@@ -15,19 +15,19 @@ using LlvmLibcCbrtfTest = LIBC_NAMESPACE::testing::FPTest<float>;
using LIBC_NAMESPACE::testing::tlog;
TEST_F(LlvmLibcCbrtfTest, SpecialNumbers) {
- // EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::cbrtf(aNaN));
- // EXPECT_FP_EQ_ALL_ROUNDING(inf, LIBC_NAMESPACE::cbrtf(inf));
- // EXPECT_FP_EQ_ALL_ROUNDING(neg_inf, LIBC_NAMESPACE::cbrtf(neg_inf));
- // EXPECT_FP_EQ_ALL_ROUNDING(zero, LIBC_NAMESPACE::cbrtf(zero));
- // EXPECT_FP_EQ_ALL_ROUNDING(neg_zero, LIBC_NAMESPACE::cbrtf(neg_zero));
- // EXPECT_FP_EQ_ALL_ROUNDING(1.0f, LIBC_NAMESPACE::cbrtf(1.0f));
- // EXPECT_FP_EQ_ALL_ROUNDING(-1.0f, LIBC_NAMESPACE::cbrtf(-1.0f));
- // EXPECT_FP_EQ_ALL_ROUNDING(2.0f, LIBC_NAMESPACE::cbrtf(8.0f));
- // EXPECT_FP_EQ_ALL_ROUNDING(-2.0f, LIBC_NAMESPACE::cbrtf(-8.0f));
+ EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::cbrtf(aNaN));
+ EXPECT_FP_EQ_ALL_ROUNDING(inf, LIBC_NAMESPACE::cbrtf(inf));
+ EXPECT_FP_EQ_ALL_ROUNDING(neg_inf, LIBC_NAMESPACE::cbrtf(neg_inf));
+ EXPECT_FP_EQ_ALL_ROUNDING(zero, LIBC_NAMESPACE::cbrtf(zero));
+ EXPECT_FP_EQ_ALL_ROUNDING(neg_zero, LIBC_NAMESPACE::cbrtf(neg_zero));
+ EXPECT_FP_EQ_ALL_ROUNDING(1.0f, LIBC_NAMESPACE::cbrtf(1.0f));
+ EXPECT_FP_EQ_ALL_ROUNDING(-1.0f, LIBC_NAMESPACE::cbrtf(-1.0f));
+ EXPECT_FP_EQ_ALL_ROUNDING(2.0f, LIBC_NAMESPACE::cbrtf(8.0f));
+ EXPECT_FP_EQ_ALL_ROUNDING(-2.0f, LIBC_NAMESPACE::cbrtf(-8.0f));
EXPECT_FP_EQ_ALL_ROUNDING(3.0f, LIBC_NAMESPACE::cbrtf(27.0f));
- // EXPECT_FP_EQ_ALL_ROUNDING(-3.0f, LIBC_NAMESPACE::cbrtf(-27.0f));
- // EXPECT_FP_EQ_ALL_ROUNDING(5.0f, LIBC_NAMESPACE::cbrtf(125.0f));
- // EXPECT_FP_EQ_ALL_ROUNDING(-5.0f, LIBC_NAMESPACE::cbrtf(-125.0f));
- // EXPECT_FP_EQ_ALL_ROUNDING(0x1.0p42f, LIBC_NAMESPACE::cbrtf(0x1.0p126f));
- // EXPECT_FP_EQ_ALL_ROUNDING(-0x1.0p42f, LIBC_NAMESPACE::cbrtf(-0x1.0p126f));
+ EXPECT_FP_EQ_ALL_ROUNDING(-3.0f, LIBC_NAMESPACE::cbrtf(-27.0f));
+ EXPECT_FP_EQ_ALL_ROUNDING(5.0f, LIBC_NAMESPACE::cbrtf(125.0f));
+ EXPECT_FP_EQ_ALL_ROUNDING(-5.0f, LIBC_NAMESPACE::cbrtf(-125.0f));
+ EXPECT_FP_EQ_ALL_ROUNDING(0x1.0p42f, LIBC_NAMESPACE::cbrtf(0x1.0p126f));
+ EXPECT_FP_EQ_ALL_ROUNDING(-0x1.0p42f, LIBC_NAMESPACE::cbrtf(-0x1.0p126f));
}
More information about the libc-commits
mailing list