diff --git a/SHARED-FILES b/SHARED-FILES
index 228f415dfd..d367f4b62f 100644
--- a/SHARED-FILES
+++ b/SHARED-FILES
@@ -268,3 +268,7 @@ sysdeps/ieee754/flt-32/s_log10p1f.c
(file src/binary32/log10p1/log10p1f.c in CORE-MATH)
- The code was adapted to use glibc code style and internal
functions to handle errno, overflow, and underflow.
+sysdeps/ieee754/flt-32/s_cbrtf.c
+ (file src/binary32/cbrt/cbrtf.c in CORE-MATH)
+ - The code was adapted to use glibc code style and internal
+ functions to handle errno, overflow, and underflow.
diff --git a/sysdeps/aarch64/libm-test-ulps b/sysdeps/aarch64/libm-test-ulps
index c523d45802..4979769b58 100644
--- a/sysdeps/aarch64/libm-test-ulps
+++ b/sysdeps/aarch64/libm-test-ulps
@@ -474,7 +474,6 @@ ldouble: 2
Function: "cbrt":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_advsimd":
@@ -483,7 +482,6 @@ float: 1
Function: "cbrt_downward":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_sve":
@@ -492,12 +490,10 @@ float: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
ldouble: 1
Function: "cbrt_upward":
double: 5
-float: 1
ldouble: 1
Function: Real part of "ccos":
diff --git a/sysdeps/alpha/fpu/libm-test-ulps b/sysdeps/alpha/fpu/libm-test-ulps
index 212c52c8cc..a2b5404f9d 100644
--- a/sysdeps/alpha/fpu/libm-test-ulps
+++ b/sysdeps/alpha/fpu/libm-test-ulps
@@ -417,22 +417,18 @@ ldouble: 2
Function: "cbrt":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_downward":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
ldouble: 1
Function: "cbrt_upward":
double: 5
-float: 1
ldouble: 1
Function: Real part of "ccos":
diff --git a/sysdeps/arc/fpu/libm-test-ulps b/sysdeps/arc/fpu/libm-test-ulps
index 7812a11b5b..c6f3646797 100644
--- a/sysdeps/arc/fpu/libm-test-ulps
+++ b/sysdeps/arc/fpu/libm-test-ulps
@@ -337,19 +337,15 @@ float: 2
Function: "cbrt":
double: 4
-float: 1
Function: "cbrt_downward":
double: 4
-float: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
Function: "cbrt_upward":
double: 5
-float: 1
Function: Real part of "ccos":
double: 3
diff --git a/sysdeps/arc/nofpu/libm-test-ulps b/sysdeps/arc/nofpu/libm-test-ulps
index d0cfa46c3d..6319012db5 100644
--- a/sysdeps/arc/nofpu/libm-test-ulps
+++ b/sysdeps/arc/nofpu/libm-test-ulps
@@ -84,7 +84,6 @@ float: 1
Function: "cbrt":
double: 4
-float: 1
Function: Real part of "ccos":
double: 1
diff --git a/sysdeps/arm/libm-test-ulps b/sysdeps/arm/libm-test-ulps
index 6cdd3d53d6..d9317046a9 100644
--- a/sysdeps/arm/libm-test-ulps
+++ b/sysdeps/arm/libm-test-ulps
@@ -333,19 +333,15 @@ float: 1
Function: "cbrt":
double: 4
-float: 1
Function: "cbrt_downward":
double: 4
-float: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
Function: "cbrt_upward":
double: 5
-float: 1
Function: Real part of "ccos":
double: 1
diff --git a/sysdeps/csky/fpu/libm-test-ulps b/sysdeps/csky/fpu/libm-test-ulps
index a7b2bec17e..c3a3db9bcb 100644
--- a/sysdeps/csky/fpu/libm-test-ulps
+++ b/sysdeps/csky/fpu/libm-test-ulps
@@ -330,19 +330,15 @@ float: 1
Function: "cbrt":
double: 4
-float: 1
Function: "cbrt_downward":
double: 4
-float: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
Function: "cbrt_upward":
double: 5
-float: 1
Function: Real part of "ccos":
double: 1
diff --git a/sysdeps/csky/nofpu/libm-test-ulps b/sysdeps/csky/nofpu/libm-test-ulps
index 4e4451a5d2..68a74bf1d0 100644
--- a/sysdeps/csky/nofpu/libm-test-ulps
+++ b/sysdeps/csky/nofpu/libm-test-ulps
@@ -328,19 +328,15 @@ float: 1
Function: "cbrt":
double: 4
-float: 1
Function: "cbrt_downward":
double: 4
-float: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
Function: "cbrt_upward":
double: 5
-float: 1
Function: Real part of "ccos":
double: 1
diff --git a/sysdeps/hppa/fpu/libm-test-ulps b/sysdeps/hppa/fpu/libm-test-ulps
index 0af5b61362..a3e66291a0 100644
--- a/sysdeps/hppa/fpu/libm-test-ulps
+++ b/sysdeps/hppa/fpu/libm-test-ulps
@@ -338,20 +338,16 @@ float: 1
Function: "cbrt":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_downward":
double: 4
-float: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
Function: "cbrt_upward":
double: 5
-float: 1
Function: Real part of "ccos":
double: 1
diff --git a/sysdeps/ieee754/flt-32/s_cbrtf.c b/sysdeps/ieee754/flt-32/s_cbrtf.c
index 68b8b0ec37..5a7a9a952d 100644
--- a/sysdeps/ieee754/flt-32/s_cbrtf.c
+++ b/sysdeps/ieee754/flt-32/s_cbrtf.c
@@ -1,61 +1,99 @@
-/* Compute cubic root of float value.
- Copyright (C) 1997-2024 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
+/* Correctly-rounded cubic root of binary32 value.
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
+Copyright (c) 2023, 2024 Alexei Sibidanov.
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
+The original version of this file was copied from the CORE-MATH
+project (file src/binary32/cbrt/cbrtf.c, revision bc385c2).
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- . */
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
-#include
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+#include
#include
-
-
-#define CBRT2 1.2599210498948731648 /* 2^(1/3) */
-#define SQR_CBRT2 1.5874010519681994748 /* 2^(2/3) */
-
-static const double factor[5] =
-{
- 1.0 / SQR_CBRT2,
- 1.0 / CBRT2,
- 1.0,
- CBRT2,
- SQR_CBRT2
-};
-
+#include
+#include
+#include "math_config.h"
float
__cbrtf (float x)
{
- float xm, ym, u, t2;
- int xe;
-
- /* Reduce X. XM now is an range 1.0 to 0.5. */
- xm = __frexpf (fabsf (x), &xe);
-
- /* If X is not finite or is null return it (with raising exceptions
- if necessary.
- Note: *Our* version of `frexp' sets XE to zero if the argument is
- Inf or NaN. This is not portable but faster. */
- if (xe == 0 && fpclassify (x) <= FP_ZERO)
- return x + x;
-
- u = (0.492659620528969547 + (0.697570460207922770
- - 0.191502161678719066 * xm) * xm);
-
- t2 = u * u * u;
-
- ym = u * (t2 + 2.0 * xm) / (2.0 * t2 + xm) * factor[2 + xe % 3];
-
- return __ldexpf (x > 0.0 ? ym : -ym, xe / 3);
+ static const union
+ {
+ double d;
+ uint64_t u;
+ } escale[3] =
+ {
+ { .d = 1.0 },
+ { .d = 0x1.428a2f98d728bp+0 }, /* 2^(1/3) */
+ { .d = 0x1.965fea53d6e3dp+0 }, /* 2^(2/3) */
+ };
+ uint32_t u = asuint (x);
+ uint32_t au = u << 1;
+ uint32_t sgn = u >> 31;
+ uint32_t e = au >> 24;
+ if (__glibc_unlikely (au < 1u << 24 || au >= 0xffu << 24))
+ {
+ if (au >= 0xffu << 24)
+ return x + x; /* inf, nan */
+ if (au == 0)
+ return x; /* +-0 */
+ int nz = __builtin_clz (au) - 7; /* subnormal */
+ au <<= nz;
+ e -= nz - 1;
+ }
+ uint32_t mant = au & 0xffffff;
+ e += 899;
+ uint32_t et = e / 3, it = e % 3;
+ uint64_t isc = escale[it].u;
+ isc += (int64_t) (et - 342) << 52;
+ isc |= (int64_t) sgn << 63;
+ double cvt2 = asdouble (isc);
+ static const double c[] =
+ {
+ 0x1.2319d352ea5d5p-1, 0x1.67ad8ee258d1ap-1, -0x1.9342edf9cbad9p-2,
+ 0x1.b6388fc510a75p-3, -0x1.6002455599e2fp-4, 0x1.7b096936192c4p-6,
+ -0x1.e5577187e8bf8p-9, 0x1.169ef81d6c34ep-12
+ };
+ double z = asdouble ((uint64_t) mant << 28 | UINT64_C(0x3ff) << 52);
+ double r0 = -0x1.9931c6c2d19d1p-6 / z;
+ double z2 = z * z;
+ double z4 = z2 * z2;
+ double f = ((c[0] + z * c[1]) + z2 * (c[2] + z * c[3]))
+ + z4 * ((c[4] + z * c[5]) + z2 * (c[6] + z * c[7])) + r0;
+ double r = f * cvt2;
+ float ub = r;
+ float lb = r - cvt2 * 1.4182e-9;
+ if (__glibc_likely (ub == lb))
+ return ub;
+ const double u0 = -0x1.ab16ec65d138fp+3;
+ double h = f * f * f - z;
+ f -= (f * r0 * u0) * h;
+ r = f * cvt2;
+ uint64_t cvt1 = asuint64 (r);
+ ub = r;
+ int64_t m0 = cvt1 << 19;
+ int64_t m1 = m0 >> 63;
+ if (__glibc_unlikely ((m0 ^ m1) < (UINT64_C(1) << 31)))
+ {
+ cvt1 = (cvt1 + (UINT64_C(1) << 31)) & UINT64_C(0xffffffff00000000);
+ ub = asdouble (cvt1);
+ }
+ return ub;
}
libm_alias_float (__cbrt, cbrt)
diff --git a/sysdeps/loongarch/lp64/libm-test-ulps b/sysdeps/loongarch/lp64/libm-test-ulps
index 7c20711268..1aaf7b3fa3 100644
--- a/sysdeps/loongarch/lp64/libm-test-ulps
+++ b/sysdeps/loongarch/lp64/libm-test-ulps
@@ -417,22 +417,18 @@ ldouble: 2
Function: "cbrt":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_downward":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
ldouble: 1
Function: "cbrt_upward":
double: 5
-float: 1
ldouble: 1
Function: Real part of "ccos":
diff --git a/sysdeps/m68k/m680x0/fpu/libm-test-ulps b/sysdeps/m68k/m680x0/fpu/libm-test-ulps
index 3964b83b81..8456a59010 100644
--- a/sysdeps/m68k/m680x0/fpu/libm-test-ulps
+++ b/sysdeps/m68k/m680x0/fpu/libm-test-ulps
@@ -379,22 +379,18 @@ ldouble: 1
Function: "cbrt":
double: 1
-float: 1
ldouble: 1
Function: "cbrt_downward":
double: 1
-float: 1
ldouble: 1
Function: "cbrt_towardzero":
double: 1
-float: 1
ldouble: 1
Function: "cbrt_upward":
double: 1
-float: 1
ldouble: 1
Function: Real part of "ccos":
diff --git a/sysdeps/microblaze/libm-test-ulps b/sysdeps/microblaze/libm-test-ulps
index 328e31582b..c89096defd 100644
--- a/sysdeps/microblaze/libm-test-ulps
+++ b/sysdeps/microblaze/libm-test-ulps
@@ -81,7 +81,6 @@ float: 1
Function: "cbrt":
double: 3
-float: 1
Function: Real part of "ccos":
double: 1
diff --git a/sysdeps/mips/mips32/libm-test-ulps b/sysdeps/mips/mips32/libm-test-ulps
index c319e0642c..cef264d649 100644
--- a/sysdeps/mips/mips32/libm-test-ulps
+++ b/sysdeps/mips/mips32/libm-test-ulps
@@ -333,19 +333,15 @@ float: 1
Function: "cbrt":
double: 4
-float: 1
Function: "cbrt_downward":
double: 4
-float: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
Function: "cbrt_upward":
double: 5
-float: 1
Function: Real part of "ccos":
double: 1
diff --git a/sysdeps/mips/mips64/libm-test-ulps b/sysdeps/mips/mips64/libm-test-ulps
index 365b860c54..724249d3ad 100644
--- a/sysdeps/mips/mips64/libm-test-ulps
+++ b/sysdeps/mips/mips64/libm-test-ulps
@@ -417,22 +417,18 @@ ldouble: 2
Function: "cbrt":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_downward":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
ldouble: 1
Function: "cbrt_upward":
double: 5
-float: 1
ldouble: 1
Function: Real part of "ccos":
diff --git a/sysdeps/nios2/libm-test-ulps b/sysdeps/nios2/libm-test-ulps
index 5240767c0e..dbccba13cb 100644
--- a/sysdeps/nios2/libm-test-ulps
+++ b/sysdeps/nios2/libm-test-ulps
@@ -84,7 +84,6 @@ float: 1
Function: "cbrt":
double: 4
-float: 1
Function: Real part of "ccos":
double: 1
diff --git a/sysdeps/or1k/fpu/libm-test-ulps b/sysdeps/or1k/fpu/libm-test-ulps
index 9ced4b0052..df2b69ac75 100644
--- a/sysdeps/or1k/fpu/libm-test-ulps
+++ b/sysdeps/or1k/fpu/libm-test-ulps
@@ -333,19 +333,15 @@ float: 1
Function: "cbrt":
double: 4
-float: 1
Function: "cbrt_downward":
double: 4
-float: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
Function: "cbrt_upward":
double: 5
-float: 1
Function: Real part of "ccos":
double: 1
diff --git a/sysdeps/or1k/nofpu/libm-test-ulps b/sysdeps/or1k/nofpu/libm-test-ulps
index c7ae0f002b..2263f3f0b7 100644
--- a/sysdeps/or1k/nofpu/libm-test-ulps
+++ b/sysdeps/or1k/nofpu/libm-test-ulps
@@ -333,19 +333,15 @@ float: 1
Function: "cbrt":
double: 4
-float: 1
Function: "cbrt_downward":
double: 4
-float: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
Function: "cbrt_upward":
double: 5
-float: 1
Function: Real part of "ccos":
double: 1
diff --git a/sysdeps/powerpc/fpu/libm-test-ulps b/sysdeps/powerpc/fpu/libm-test-ulps
index 8d0c18eed1..36fa54d97e 100644
--- a/sysdeps/powerpc/fpu/libm-test-ulps
+++ b/sysdeps/powerpc/fpu/libm-test-ulps
@@ -506,25 +506,21 @@ ldouble: 6
Function: "cbrt":
double: 4
-float: 1
float128: 1
ldouble: 1
Function: "cbrt_downward":
double: 4
-float: 1
float128: 1
ldouble: 5
Function: "cbrt_towardzero":
double: 3
-float: 1
float128: 1
ldouble: 3
Function: "cbrt_upward":
double: 5
-float: 1
float128: 2
ldouble: 2
diff --git a/sysdeps/powerpc/nofpu/libm-test-ulps b/sysdeps/powerpc/nofpu/libm-test-ulps
index 20036c779c..c32c8017b4 100644
--- a/sysdeps/powerpc/nofpu/libm-test-ulps
+++ b/sysdeps/powerpc/nofpu/libm-test-ulps
@@ -421,22 +421,18 @@ ldouble: 6
Function: "cbrt":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_downward":
double: 4
-float: 1
ldouble: 5
Function: "cbrt_towardzero":
double: 3
-float: 1
ldouble: 3
Function: "cbrt_upward":
double: 5
-float: 1
ldouble: 2
Function: Real part of "ccos":
diff --git a/sysdeps/riscv/nofpu/libm-test-ulps b/sysdeps/riscv/nofpu/libm-test-ulps
index cccc864a7a..79927c2bd9 100644
--- a/sysdeps/riscv/nofpu/libm-test-ulps
+++ b/sysdeps/riscv/nofpu/libm-test-ulps
@@ -417,22 +417,18 @@ ldouble: 2
Function: "cbrt":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_downward":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
ldouble: 1
Function: "cbrt_upward":
double: 5
-float: 1
ldouble: 1
Function: Real part of "ccos":
diff --git a/sysdeps/riscv/rvd/libm-test-ulps b/sysdeps/riscv/rvd/libm-test-ulps
index 14fc7633af..fbd5b8fed7 100644
--- a/sysdeps/riscv/rvd/libm-test-ulps
+++ b/sysdeps/riscv/rvd/libm-test-ulps
@@ -417,22 +417,18 @@ ldouble: 2
Function: "cbrt":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_downward":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
ldouble: 1
Function: "cbrt_upward":
double: 5
-float: 1
ldouble: 1
Function: Real part of "ccos":
diff --git a/sysdeps/s390/fpu/libm-test-ulps b/sysdeps/s390/fpu/libm-test-ulps
index a25bb505b3..ade5a39db4 100644
--- a/sysdeps/s390/fpu/libm-test-ulps
+++ b/sysdeps/s390/fpu/libm-test-ulps
@@ -417,22 +417,18 @@ ldouble: 2
Function: "cbrt":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_downward":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
ldouble: 1
Function: "cbrt_upward":
double: 5
-float: 1
ldouble: 1
Function: Real part of "ccos":
diff --git a/sysdeps/sh/libm-test-ulps b/sysdeps/sh/libm-test-ulps
index 8562796de8..b0040d7218 100644
--- a/sysdeps/sh/libm-test-ulps
+++ b/sysdeps/sh/libm-test-ulps
@@ -164,11 +164,9 @@ float: 2
Function: "cbrt":
double: 4
-float: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
Function: Real part of "ccos":
double: 1
diff --git a/sysdeps/sparc/fpu/libm-test-ulps b/sysdeps/sparc/fpu/libm-test-ulps
index 6ea02058e9..d78b46b97b 100644
--- a/sysdeps/sparc/fpu/libm-test-ulps
+++ b/sysdeps/sparc/fpu/libm-test-ulps
@@ -417,22 +417,18 @@ ldouble: 2
Function: "cbrt":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_downward":
double: 4
-float: 1
ldouble: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
ldouble: 1
Function: "cbrt_upward":
double: 5
-float: 1
ldouble: 1
Function: Real part of "ccos":
diff --git a/sysdeps/x86_64/fpu/libm-test-ulps b/sysdeps/x86_64/fpu/libm-test-ulps
index e3c811549c..327937929d 100644
--- a/sysdeps/x86_64/fpu/libm-test-ulps
+++ b/sysdeps/x86_64/fpu/libm-test-ulps
@@ -638,25 +638,21 @@ ldouble: 1
Function: "cbrt":
double: 4
-float: 1
float128: 1
ldouble: 1
Function: "cbrt_downward":
double: 4
-float: 1
float128: 1
ldouble: 1
Function: "cbrt_towardzero":
double: 3
-float: 1
float128: 1
ldouble: 1
Function: "cbrt_upward":
double: 5
-float: 1
float128: 1
ldouble: 1