math: Use tanpif from CORE-MATH

The CORE-MATH implementation is correctly rounded (for any rounding mode) and shows better performance to the generic tanpif. The code was adapted to glibc style and to use the definition of math_config.h (to handle errno, overflow, and underflow). Benchtest on x64_64 (Ryzen 9 5900X, gcc 14.2.1), aarch64 (Neoverse-N1, gcc 13.3.1), and powerpc (POWER10, gcc 13.2.1): latency master patched improvement x86_64 85.1683 47.7990 43.88% x86_64v2 76.8219 41.4679 46.02% x86_64v3 73.7775 37.7734 48.80% aarch64 (Neoverse) 35.4514 18.0742 49.02% power8 22.7604 10.1054 55.60% power10 22.1358 9.9553 55.03% reciprocal-throughput master patched improvement x86_64 41.0174 19.4718 52.53% x86_64v2 34.8565 11.3761 67.36% x86_64v3 34.0325 9.6989 71.50% aarch64 (Neoverse) 25.4349 9.2017 63.82% power8 13.8626 3.8486 72.24% power10 11.7933 3.6420 69.12% Reviewed-by: DJ Delorie <dj@redhat.com>
2025-02-17 13:00:43 +08:00 · 2024-12-20 13:38:40 -03:00 · 2024-12-20 13:38:40 -03:00 · 8f170dc819
commit 8f170dc819
parent de2fca9fe2
21 changed files with 120 additions and 59 deletions
--- a/4
+++ b/4
@ -358,3 +358,7 @@ sysdeps/ieee754/flt-32/s_sinpif.c:
  (src/binary32/sinpi/sinpif.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_tanpif.c:
+  (src/binary32/tanpi/tanpif.c in CORE-MATH)
+  - the code was adapted to use glibc code style and internal
+    functions to handle errno, overflow, and underflow.
--- a/sysdeps/aarch64/libm-test-ulps
+++ b/sysdeps/aarch64/libm-test-ulps
@ -1681,7 +1681,6 @@ ldouble: 3

 Function: "tanpi":
 double: 3
-float: 3
 ldouble: 3

 Function: "tanpi_advsimd":
@ -1690,7 +1689,6 @@ float: 2

 Function: "tanpi_downward":
 double: 2
-float: 3
 ldouble: 4

 Function: "tanpi_sve":
@ -1699,12 +1697,10 @@ float: 2

 Function: "tanpi_towardzero":
 double: 2
-float: 3
 ldouble: 4

 Function: "tanpi_upward":
 double: 2
-float: 4
 ldouble: 4

 Function: "tgamma":
--- a/sysdeps/arc/fpu/libm-test-ulps
+++ b/sysdeps/arc/fpu/libm-test-ulps
@ -1137,19 +1137,15 @@ double: 3

 Function: "tanpi":
 double: 3
-float: 3

 Function: "tanpi_downward":
 double: 2
-float: 3

 Function: "tanpi_towardzero":
 double: 2
-float: 3

 Function: "tanpi_upward":
 double: 2
-float: 4

 Function: "tgamma":
 double: 9
--- a/sysdeps/arc/nofpu/libm-test-ulps
+++ b/sysdeps/arc/nofpu/libm-test-ulps
@ -271,7 +271,6 @@ double: 2

 Function: "tanpi":
 double: 3
-float: 3

 Function: "tgamma":
 double: 9
--- a/sysdeps/arm/libm-test-ulps
+++ b/sysdeps/arm/libm-test-ulps
@ -1130,19 +1130,15 @@ double: 3

 Function: "tanpi":
 double: 3
-float: 3

 Function: "tanpi_downward":
 double: 2
-float: 3

 Function: "tanpi_towardzero":
 double: 2
-float: 3

 Function: "tanpi_upward":
 double: 2
-float: 4

 Function: "tgamma":
 double: 9
--- a/sysdeps/hppa/fpu/libm-test-ulps
+++ b/sysdeps/hppa/fpu/libm-test-ulps
@ -1160,19 +1160,15 @@ double: 3

 Function: "tanpi":
 double: 3
-float: 3

 Function: "tanpi_downward":
 double: 2
-float: 3

 Function: "tanpi_towardzero":
 double: 2
-float: 3

 Function: "tanpi_upward":
 double: 2
-float: 4

 Function: "tgamma":
 double: 9
--- a/sysdeps/i386/fpu/libm-test-ulps
+++ b/sysdeps/i386/fpu/libm-test-ulps
@ -1750,25 +1750,21 @@ ldouble: 4

 Function: "tanpi":
 double: 3
-float: 3
 float128: 3
 ldouble: 3

 Function: "tanpi_downward":
 double: 2
-float: 3
 float128: 4
 ldouble: 4

 Function: "tanpi_towardzero":
 double: 2
-float: 3
 float128: 4
 ldouble: 4

 Function: "tanpi_upward":
 double: 2
-float: 4
 float128: 4
 ldouble: 4

--- a/sysdeps/i386/i686/fpu/multiarch/libm-test-ulps
+++ b/sysdeps/i386/i686/fpu/multiarch/libm-test-ulps
@ -1755,25 +1755,21 @@ ldouble: 4

 Function: "tanpi":
 double: 3
-float: 3
 float128: 3
 ldouble: 3

 Function: "tanpi_downward":
 double: 2
-float: 3
 float128: 4
 ldouble: 4

 Function: "tanpi_towardzero":
 double: 2
-float: 3
 float128: 4
 ldouble: 4

 Function: "tanpi_upward":
 double: 2
-float: 4
 float128: 4
 ldouble: 4

--- a/sysdeps/ieee754/flt-32/math_config.h
+++ b/sysdeps/ieee754/flt-32/math_config.h
@ -84,6 +84,31 @@ roundeven_finite (double x)
 #endif
 }

+#ifndef ROUNDEVENF_INTRINSICS
+/* When set, roundevenf_finite will route to the internal roundevenf function.  */
+# define ROUNDEVENF_INTRINSICS 1
+#endif
+
+static inline float
+roundevenf_finite (float x)
+{
+  if (!isfinite (x))
+    __builtin_unreachable ();
+#if ROUNDEVENF_INTRINSICS
+  return roundevenf (x);
+#else
+  float y = roundf (x);
+  if (fabs (x - y) == 0.5)
+    {
+      union { float f; uint32_t i; } u = {y};
+      union { float f; uint32_t i; } v = {y - copysignf (1.0, x)};
+      if (__builtin_ctzl (v.i) > __builtin_ctzl (u.i))
+        y = v.f;
+    }
+  return y;
+#endif
+}
+
 static inline uint32_t
 asuint (float f)
 {
--- a/sysdeps/ieee754/flt-32/s_tanpif.c
+++ b/sysdeps/ieee754/flt-32/s_tanpif.c
@ -0,0 +1,90 @@
+/* Correctly-rounded tangent of binary32 value for angles in half-revolutions
+
+Copyright (c) 2022-2025 Alexei Sibidanov.
+
+The original version of this file was copied from the CORE-MATH
+project (src/binary32/tanpi/tanpif.c, revision 3bbf907).
+
+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:
+
+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 <stdint.h>
+#include <errno.h>
+#include <libm-alias-float.h>
+#include "math_config.h"
+
+float
+__tanpif (float x)
+{
+  uint32_t ix = asuint (x);
+  uint32_t e = ix & (0xff << 23);
+  if (__glibc_unlikely (e > (150 << 23))) /* |x| > 2^23 */
+    {
+      if (e == (0xff << 23)) /* x = nan or inf */
+	{
+	  if (!(ix << 9)) /* x = inf */
+	    return __math_invalidf (x);
+	  return x + x; /* x = nan */
+	}
+      return copysign (0.0f, x);
+    }
+  float x4 = 4.0f * x;
+  float nx4 = roundevenf_finite (x4);
+  float dx4 = x4 - nx4;
+  float ni = roundevenf_finite (x);
+  float zf = x - ni;
+  if (__glibc_unlikely (dx4 == 0.0f)) /* 4*x integer */
+    {
+      int k = x4;
+      if (k & 1)
+	return copysignf (1.0f, zf); /* x = 1/4 mod 1/2 */
+      k &= 7;
+      if (k == 0)
+	return copysignf (0.0f, x); /* x = 0 mod 2 */
+      if (k == 4)
+	return -copysignf (0.0f, x); /*  x = 1 mod 2 */
+      __set_errno (ERANGE);
+      if (k == 2)
+	return 1.0f / 0.0f; /* x = 1/2 mod 2 */
+      if (k == 6)
+	return -1.0f / 0.0f; /* x = -1/2 mod 2 */
+    }
+  ix = asuint (zf);
+  uint32_t a = ix & (~0u >> 1);
+  /* x=0x1.267004p-2 is not correctly rounded for RNDZ/RNDD by the code below */
+  if (__glibc_unlikely (a == 0x3e933802u))
+    return copysignf (0x1.44cfbap+0f, zf) + copysignf (0x1p-25f, zf);
+  /* x=-0x1.e4cd0ap-14 is not correctly rounded for RNDU by the code below */
+  if (__glibc_unlikely (a == 0x38f26685u))
+    return copysignf (0x1.7cc304p-12, zf) + copysignf (0x1p-37f, zf);
+
+  double z = zf, z2 = z * z;
+
+  static const double cn[] = { 0x1.921fb54442d19p-1, -0x1.1f458b3e1f8d6p-2,
+			       0x1.68a34bd0b8f6ap-6, -0x1.e4866f7a25f99p-13 };
+  static const double cd[] = { 0x1p+0, -0x1.4b4b98d2df3a7p-1,
+			       0x1.8e9926d2bb901p-4, -0x1.a6f77fd847eep-9 };
+  double z4
+      = z2 * z2,
+      r = (z - z * z2) * ((cn[0] + z2 * cn[1]) + z4 * (cn[2] + z2 * cn[3]))
+	  / (((cd[0] + z2 * cd[1]) + z4 * (cd[2] + z2 * cd[3])) * (0.25 - z2));
+  return r;
+}
+libm_alias_float (__tanpi, tanpi)
--- a/sysdeps/loongarch/lp64/libm-test-ulps
+++ b/sysdeps/loongarch/lp64/libm-test-ulps
@ -1437,22 +1437,18 @@ ldouble: 3

 Function: "tanpi":
 double: 3
-float: 3
 ldouble: 3

 Function: "tanpi_downward":
 double: 2
-float: 3
 ldouble: 4

 Function: "tanpi_towardzero":
 double: 2
-float: 3
 ldouble: 4

 Function: "tanpi_upward":
 double: 2
-float: 4
 ldouble: 4

 Function: "tgamma":
--- a/sysdeps/mips/mips64/libm-test-ulps
+++ b/sysdeps/mips/mips64/libm-test-ulps
@ -1449,22 +1449,18 @@ ldouble: 3

 Function: "tanpi":
 double: 3
-float: 3
 ldouble: 3

 Function: "tanpi_downward":
 double: 2
-float: 3
 ldouble: 4

 Function: "tanpi_towardzero":
 double: 2
-float: 3
 ldouble: 4

 Function: "tanpi_upward":
 double: 2
-float: 4
 ldouble: 4

 Function: "tgamma":
--- a/sysdeps/or1k/fpu/libm-test-ulps
+++ b/sysdeps/or1k/fpu/libm-test-ulps
@ -1115,19 +1115,15 @@ double: 3

 Function: "tanpi":
 double: 3
-float: 3

 Function: "tanpi_downward":
 double: 2
-float: 3

 Function: "tanpi_towardzero":
 double: 2
-float: 3

 Function: "tanpi_upward":
 double: 2
-float: 4

 Function: "tgamma":
 double: 9
--- a/sysdeps/or1k/nofpu/libm-test-ulps
+++ b/sysdeps/or1k/nofpu/libm-test-ulps
@ -1015,7 +1015,6 @@ double: 3

 Function: "tanpi":
 double: 3
-float: 3

 Function: "tgamma":
 double: 9
--- a/sysdeps/powerpc/fpu/libm-test-ulps
+++ b/sysdeps/powerpc/fpu/libm-test-ulps
@ -1857,25 +1857,21 @@ ldouble: 6

 Function: "tanpi":
 double: 3
-float: 3
 float128: 2
 ldouble: 2

 Function: "tanpi_downward":
 double: 2
-float: 3
 float128: 4
 ldouble: 8

 Function: "tanpi_towardzero":
 double: 2
-float: 3
 float128: 4
 ldouble: 8

 Function: "tanpi_upward":
 double: 2
-float: 4
 float128: 4
 ldouble: 8

--- a/sysdeps/powerpc/fpu/math_private.h
+++ b/sysdeps/powerpc/fpu/math_private.h
@ -62,6 +62,7 @@ __ieee754_sqrtf128 (_Float128 __x)
 #ifdef _ARCH_PWR6
 /* ISA 2.03 provides frin/round() and cntlzw/ctznll().  */
 # define ROUNDEVEN_INTRINSICS 0
+# define ROUNDEVENF_INTRINSICS 0
 #endif

 #endif /* _PPC_MATH_PRIVATE_H_ */
--- a/sysdeps/riscv/nofpu/libm-test-ulps
+++ b/sysdeps/riscv/nofpu/libm-test-ulps
@ -1306,7 +1306,6 @@ ldouble: 3

 Function: "tanpi":
 double: 3
-float: 3
 ldouble: 3

 Function: "tgamma":
--- a/sysdeps/riscv/rvd/libm-test-ulps
+++ b/sysdeps/riscv/rvd/libm-test-ulps
@ -1452,22 +1452,18 @@ ldouble: 3

 Function: "tanpi":
 double: 3
-float: 3
 ldouble: 3

 Function: "tanpi_downward":
 double: 2
-float: 3
 ldouble: 4

 Function: "tanpi_towardzero":
 double: 2
-float: 3
 ldouble: 4

 Function: "tanpi_upward":
 double: 2
-float: 4
 ldouble: 4

 Function: "tgamma":
--- a/sysdeps/s390/fpu/libm-test-ulps
+++ b/sysdeps/s390/fpu/libm-test-ulps
@ -1434,22 +1434,18 @@ ldouble: 3

 Function: "tanpi":
 double: 3
-float: 3
 ldouble: 3

 Function: "tanpi_downward":
 double: 2
-float: 3
 ldouble: 4

 Function: "tanpi_towardzero":
 double: 2
-float: 3
 ldouble: 4

 Function: "tanpi_upward":
 double: 2
-float: 4
 ldouble: 4

 Function: "tgamma":
--- a/sysdeps/sparc/fpu/libm-test-ulps
+++ b/sysdeps/sparc/fpu/libm-test-ulps
@ -1449,22 +1449,18 @@ ldouble: 3

 Function: "tanpi":
 double: 3
-float: 3
 ldouble: 3

 Function: "tanpi_downward":
 double: 2
-float: 3
 ldouble: 4

 Function: "tanpi_towardzero":
 double: 2
-float: 3
 ldouble: 4

 Function: "tanpi_upward":
 double: 2
-float: 4
 ldouble: 4

 Function: "tgamma":
--- a/sysdeps/x86_64/fpu/libm-test-ulps
+++ b/sysdeps/x86_64/fpu/libm-test-ulps
@ -2292,25 +2292,21 @@ double: 1

 Function: "tanpi":
 double: 3
-float: 3
 float128: 3
 ldouble: 3

 Function: "tanpi_downward":
 double: 2
-float: 3
 float128: 4
 ldouble: 4

 Function: "tanpi_towardzero":
 double: 2
-float: 3
 float128: 4
 ldouble: 4

 Function: "tanpi_upward":
 double: 2
-float: 4
 float128: 4
 ldouble: 4