From 599cf3976679e1b345307d9c02057f02aa95528f Mon Sep 17 00:00:00 2001 From: Wilco Dijkstra Date: Tue, 14 Aug 2018 10:45:59 +0100 Subject: Improve performance of sinf and cosf The second patch improves performance of sinf and cosf using the same algorithms and polynomials. The returned values are identical to sincosf for the same input. ULP definitions for AArch64 and x64 are updated. sinf/cosf througput gains on Cortex-A72: * |x| < 0x1p-12 : 1.2x * |x| < M_PI_4 : 1.8x * |x| < 2 * M_PI: 1.7x * |x| < 120.0 : 2.3x * |x| < Inf : 3.0x * NEWS: Mention sinf, cosf, sincosf. * sysdeps/aarch64/libm-test-ulps: Update ULP for sinf, cosf, sincosf. * sysdeps/x86_64/fpu/libm-test-ulps: Update ULP for sinf and cosf. * sysdeps/x86_64/fpu/multiarch/s_sincosf-fma.c: Add definitions of constants rather than including generic sincosf.h. * sysdeps/x86_64/fpu/s_sincosf_data.c: Remove. * sysdeps/ieee754/flt-32/s_cosf.c (cosf): Rewrite. * sysdeps/ieee754/flt-32/s_sincosf.h (reduced_sin): Remove. (reduced_cos): Remove. (sinf_poly): New function. * sysdeps/ieee754/flt-32/s_sinf.c (sinf): Rewrite. --- sysdeps/x86_64/fpu/libm-test-ulps | 12 ++++++++++ sysdeps/x86_64/fpu/multiarch/s_sincosf-fma.c | 33 +++++++++++++++++++++++++++- sysdeps/x86_64/fpu/s_sincosf_data.c | 1 - 3 files changed, 44 insertions(+), 2 deletions(-) delete mode 100644 sysdeps/x86_64/fpu/s_sincosf_data.c (limited to 'sysdeps/x86_64') diff --git a/sysdeps/x86_64/fpu/libm-test-ulps b/sysdeps/x86_64/fpu/libm-test-ulps index 912db318b6..a51faecfc7 100644 --- a/sysdeps/x86_64/fpu/libm-test-ulps +++ b/sysdeps/x86_64/fpu/libm-test-ulps @@ -1271,24 +1271,30 @@ ldouble: 1 Function: "cos_downward": double: 1 +float: 1 float128: 3 idouble: 1 +ifloat: 1 ifloat128: 3 ildouble: 3 ldouble: 3 Function: "cos_towardzero": double: 1 +float: 1 float128: 1 idouble: 1 +ifloat: 1 ifloat128: 1 ildouble: 2 ldouble: 2 Function: "cos_upward": double: 1 +float: 1 float128: 2 idouble: 1 +ifloat: 1 ifloat128: 2 ildouble: 2 ldouble: 2 @@ -2539,24 +2545,30 @@ ldouble: 1 Function: "sin_downward": double: 1 +float: 1 float128: 3 idouble: 1 +ifloat:1 ifloat128: 3 ildouble: 3 ldouble: 3 Function: "sin_towardzero": double: 1 +float:1 float128: 2 idouble: 1 +ifloat: 1 ifloat128: 2 ildouble: 2 ldouble: 2 Function: "sin_upward": double: 1 +float:1 float128: 3 idouble: 1 +ifloat: 1 ifloat128: 3 ildouble: 3 ldouble: 3 diff --git a/sysdeps/x86_64/fpu/multiarch/s_sincosf-fma.c b/sysdeps/x86_64/fpu/multiarch/s_sincosf-fma.c index 64abe7abca..0b80c4fe0d 100644 --- a/sysdeps/x86_64/fpu/multiarch/s_sincosf-fma.c +++ b/sysdeps/x86_64/fpu/multiarch/s_sincosf-fma.c @@ -21,7 +21,6 @@ #include #include #include -#include "s_sincosf.h" #define SINCOSF __sincosf_fma @@ -31,6 +30,38 @@ # define SINCOSF_FUNC SINCOSF #endif +/* PI/2 with 98 bits of accuracy. */ +static const double PI_2_hi = 0x1.921fb544p+0; +static const double PI_2_lo = 0x1.0b4611a626332p-34; + +static const double SMALL = 0x1p-50; /* 2^-50. */ +static const double inv_PI_4 = 0x1.45f306dc9c883p+0; /* 4/PI. */ + +#define FLOAT_EXPONENT_SHIFT 23 +#define FLOAT_EXPONENT_BIAS 127 + +static const double pio2_table[] = { + 0 * M_PI_2, + 1 * M_PI_2, + 2 * M_PI_2, + 3 * M_PI_2, + 4 * M_PI_2, + 5 * M_PI_2 +}; + +static const double invpio4_table[] = { + 0x0p+0, + 0x1.45f306cp+0, + 0x1.c9c882ap-28, + 0x1.4fe13a8p-58, + 0x1.f47d4dp-85, + 0x1.bb81b6cp-112, + 0x1.4acc9ep-142, + 0x1.0e4107cp-169 +}; + +static const double ones[] = { 1.0, -1.0 }; + /* Chebyshev constants for sin and cos, range -PI/4 - PI/4. */ static const __v2df V0 = { -0x1.5555555551cd9p-3, -0x1.ffffffffe98aep-2}; static const __v2df V1 = { 0x1.1111110c2688bp-7, 0x1.55555545c50c7p-5 }; diff --git a/sysdeps/x86_64/fpu/s_sincosf_data.c b/sysdeps/x86_64/fpu/s_sincosf_data.c deleted file mode 100644 index 1cc8931700..0000000000 --- a/sysdeps/x86_64/fpu/s_sincosf_data.c +++ /dev/null @@ -1 +0,0 @@ -/* Not needed. */ -- cgit 1.4.1