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authorH.J. Lu <hjl.tools@gmail.com>2018-12-26 06:56:04 -0800
committerH.J. Lu <hjl.tools@gmail.com>2018-12-26 06:56:13 -0800
commit8700a7851bccce63335f937f930382de58b8a249 (patch)
tree291a8851ca6b3fb2077226741126fce06e70a948 /sysdeps/x86/fpu
parent57b3ff8e1a4ca8118c5d9a47584e6e0ce6f7002f (diff)
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x86-64: Vectorize sincosf_poly and update s_sincosf-fma.c
Add <sincosf_poly.h> and include it in s_sincosf.h to allow vectorized
sincosf_poly.  Add x86 sincosf_poly.h to vectorize sincosf_poly.  On
Broadwell, bench-sincosf shows:

       Before         After      Improvement
max    160.273        114.198        40%
min    6.25           5.625          11%
mean   13.0325        10.6462        22%

Vectorized sincosf_poly shows

       Before         After      Improvement
max    138.653        114.198        21%
min    5.004          5.625          -11%
mean   11.5934        10.6462        9%

Tested on x86-64 and i686 as well as with build-many-glibcs.py.

	* sysdeps/ieee754/flt-32/s_sincosf.h: Include <sincosf_poly.h>.
	(sincos_t, sincosf_poly, sinf_poly): Moved to ...
	* sysdeps/ieee754/flt-32/sincosf_poly.h: Here.  New file.
	* sysdeps/x86/fpu/s_sincosf_data.c: New file.
	* sysdeps/x86/fpu/sincosf_poly.h: Likewise.
	* sysdeps/x86_64/fpu/multiarch/s_sincosf-fma.c: Just include
	<sysdeps/ieee754/flt-32/s_sincosf.c>.
Diffstat (limited to 'sysdeps/x86/fpu')
-rw-r--r--sysdeps/x86/fpu/s_sincosf_data.c68
-rw-r--r--sysdeps/x86/fpu/sincosf_poly.h111
2 files changed, 179 insertions, 0 deletions
diff --git a/sysdeps/x86/fpu/s_sincosf_data.c b/sysdeps/x86/fpu/s_sincosf_data.c
new file mode 100644
index 0000000000..b219644884
--- /dev/null
+++ b/sysdeps/x86/fpu/s_sincosf_data.c
@@ -0,0 +1,68 @@
+/* Compute sine and cosine of argument.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   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.
+
+   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.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <stdint.h>
+#include <math.h>
+#include <sysdeps/ieee754/flt-32/math_config.h>
+#include <s_sincosf.h>
+
+/* The constants and polynomials for sine and cosine.  The 2nd entry
+   computes -cos (x) rather than cos (x) to get negation for free.  */
+const sincos_t __sincosf_table[2] =
+{
+  {
+    { 1.0, -1.0, -1.0, 1.0 },
+#if TOINT_INTRINSICS
+    0x1.45F306DC9C883p-1,
+#else
+    0x1.45F306DC9C883p+23,
+#endif
+    0x1.921FB54442D18p0,
+    0x1p0,
+    -0x1.ffffffd0c621cp-2,
+    { -0x1.555545995a603p-3, 0x1.55553e1068f19p-5 },
+    { 0x1.1107605230bc4p-7, -0x1.6c087e89a359dp-10 },
+    { -0x1.994eb3774cf24p-13, 0x1.99343027bf8c3p-16 }
+  },
+  {
+    { 1.0, -1.0, -1.0, 1.0 },
+#if TOINT_INTRINSICS
+    0x1.45F306DC9C883p-1,
+#else
+    0x1.45F306DC9C883p+23,
+#endif
+    0x1.921FB54442D18p0,
+    -0x1p0,
+    0x1.ffffffd0c621cp-2,
+    { -0x1.555545995a603p-3, -0x1.55553e1068f19p-5 },
+    { 0x1.1107605230bc4p-7, 0x1.6c087e89a359dp-10 },
+    { -0x1.994eb3774cf24p-13, -0x1.99343027bf8c3p-16 }
+  }
+};
+
+/* Table with 4/PI to 192 bit precision.  To avoid unaligned accesses
+   only 8 new bits are added per entry, making the table 4 times larger.  */
+const uint32_t __inv_pio4[24] =
+{
+  0xa2,       0xa2f9,	  0xa2f983,   0xa2f9836e,
+  0xf9836e4e, 0x836e4e44, 0x6e4e4415, 0x4e441529,
+  0x441529fc, 0x1529fc27, 0x29fc2757, 0xfc2757d1,
+  0x2757d1f5, 0x57d1f534, 0xd1f534dd, 0xf534ddc0,
+  0x34ddc0db, 0xddc0db62, 0xc0db6295, 0xdb629599,
+  0x6295993c, 0x95993c43, 0x993c4390, 0x3c439041
+};
diff --git a/sysdeps/x86/fpu/sincosf_poly.h b/sysdeps/x86/fpu/sincosf_poly.h
new file mode 100644
index 0000000000..396ba8993d
--- /dev/null
+++ b/sysdeps/x86/fpu/sincosf_poly.h
@@ -0,0 +1,111 @@
+/* Used by sinf, cosf and sincosf functions.  X86-64 version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   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.
+
+   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.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+typedef double v2df_t __attribute__ ((vector_size (2 * sizeof (double))));
+
+#ifdef __SSE2_MATH__
+typedef float v4sf_t __attribute__ ((vector_size (4 * sizeof (float))));
+
+static inline void
+v2df_to_sf (v2df_t v2df, float *f0p, float *f1p)
+{
+  v4sf_t v4sf = __builtin_ia32_cvtpd2ps (v2df);
+  *f0p = v4sf[0];
+  *f1p = v4sf[1];
+}
+#else
+static inline void
+v2df_to_sf (v2df_t v2df, float *f0p, float *f1p)
+{
+  *f0p = (float) v2df[0];
+  *f1p = (float) v2df[1];
+}
+#endif
+
+/* The constants and polynomials for sine and cosine.  */
+typedef struct
+{
+  double sign[4];		/* Sign of sine in quadrants 0..3.  */
+  double hpi_inv;		/* 2 / PI ( * 2^24 if !TOINT_INTRINSICS).  */
+  double hpi;			/* PI / 2.  */
+  /* Cosine polynomial: c0, c1, c2, c3, c4.
+     Sine polynomial: s1, s2, s3.  */
+  double c0, c1;
+  v2df_t s1c2, s2c3, s3c4;
+} sincos_t;
+
+/* Compute the sine and cosine of inputs X and X2 (X squared), using the
+   polynomial P and store the results in SINP and COSP.  N is the quadrant,
+   if odd the cosine and sine polynomials are swapped.  */
+static inline void
+sincosf_poly (double x, double x2, const sincos_t *p, int n, float *sinp,
+	      float *cosp)
+{
+  v2df_t vx2x2 = { x2, x2 };
+  v2df_t vxx2 = { x, x2 };
+  v2df_t vx3x4, vs1c2;
+
+  vx3x4 = vx2x2 * vxx2;
+  vs1c2 = p->s2c3 + vx2x2 * p->s3c4;
+
+  /* Swap sin/cos result based on quadrant.  */
+  if (n & 1)
+    {
+      float *tmp = cosp;
+      cosp = sinp;
+      sinp = tmp;
+    }
+
+  double c1 = p->c0 + x2 * p->c1;
+  v2df_t vxc1 = { x, c1 };
+  v2df_t vx5x6 = vx3x4 * vx2x2;
+
+  v2df_t vsincos = vxc1 + vx3x4 * p->s1c2;
+  vsincos = vsincos + vx5x6 * vs1c2;
+  v2df_to_sf (vsincos, sinp, cosp);
+}
+
+/* Return the sine of inputs X and X2 (X squared) using the polynomial P.
+   N is the quadrant, and if odd the cosine polynomial is used.  */
+static inline float
+sinf_poly (double x, double x2, const sincos_t *p, int n)
+{
+  double x3, x4, x6, x7, s, c, c1, c2, s1;
+
+  if ((n & 1) == 0)
+    {
+      x3 = x * x2;
+      s1 = p->s2c3[0] + x2 * p->s3c4[0];
+
+      x7 = x3 * x2;
+      s = x + x3 * p->s1c2[0];
+
+      return s + x7 * s1;
+    }
+  else
+    {
+      x4 = x2 * x2;
+      c2 = p->s2c3[1] + x2 * p->s3c4[1];
+      c1 = p->c0 + x2 * p->c1;
+
+      x6 = x4 * x2;
+      c = c1 + x4 * p->s1c2[1];
+
+      return c + x6 * c2;
+    }
+}