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author | H.J. Lu <hjl.tools@gmail.com> | 2017-10-22 07:49:36 -0700 |
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committer | H.J. Lu <hjl.tools@gmail.com> | 2017-10-22 07:49:55 -0700 |
commit | e1f59bebd885c442c14df3554da9fe08792ce7ce (patch) | |
tree | 2a8d4b88a4373cc77e4085d050d806b7bd216549 /sysdeps/x86_64/fpu/e_expf.S | |
parent | a159b53fa059947cc2548e3b0d5bdcf7b9630ba8 (diff) | |
download | glibc-e1f59bebd885c442c14df3554da9fe08792ce7ce.tar glibc-e1f59bebd885c442c14df3554da9fe08792ce7ce.tar.gz glibc-e1f59bebd885c442c14df3554da9fe08792ce7ce.tar.bz2 glibc-e1f59bebd885c442c14df3554da9fe08792ce7ce.zip |
x86-64: Replace assembly versions of e_expf with generic e_expf.c
This patch replaces x86-64 assembly versions of e_expf with generic
e_expf.c. For workload-spec2017.wrf, on Nehalem, it improves
performance by:
Before After Improvement
reciprocal-throughput 36.039 20.7749 73%
latency 58.8096 40.8715 43%
On Skylake, it improves
Before After Improvement
reciprocal-throughput 18.4436 11.1693 65%
latency 47.5162 37.5411 26%
* sysdeps/x86_64/fpu/e_expf.S: Removed.
* sysdeps/x86_64/fpu/multiarch/e_expf-fma.S: Likewise.
* sysdeps/x86_64/fpu/w_expf.c: Likewise.
* sysdeps/x86_64/fpu/libm-test-ulps: Updated for generic
e_expf.c.
* sysdeps/x86_64/fpu/multiarch/Makefile (CFLAGS-e_expf-fma.c):
New.
* sysdeps/x86_64/fpu/multiarch/e_expf-fma.c: New file.
* sysdeps/x86_64/fpu/multiarch/e_expf.c (__redirect_ieee754_expf):
Renamed to ...
(__redirect_expf): This.
(SYMBOL_NAME): Changed to expf.
(__ieee754_expf): Renamed to ...
(__expf): This.
(__GI___expf): This.
(__ieee754_expf): Add strong_alias.
(__expf_finite): Likewise.
(__expf): New.
Include <sysdeps/ieee754/flt-32/e_expf.c>.
Diffstat (limited to 'sysdeps/x86_64/fpu/e_expf.S')
-rw-r--r-- | sysdeps/x86_64/fpu/e_expf.S | 339 |
1 files changed, 0 insertions, 339 deletions
diff --git a/sysdeps/x86_64/fpu/e_expf.S b/sysdeps/x86_64/fpu/e_expf.S deleted file mode 100644 index c3bf312c44..0000000000 --- a/sysdeps/x86_64/fpu/e_expf.S +++ /dev/null @@ -1,339 +0,0 @@ -/* Optimized __ieee754_expf function. - Copyright (C) 2012-2017 Free Software Foundation, Inc. - Contributed by Intel Corporation. - 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 <sysdep.h> - -/* Short algorithm description: - * - * Let K = 64 (table size). - * e^x = 2^(x/log(2)) = 2^n * T[j] * (1 + P(y)) - * where - * x = m*log(2)/K + y, y in [0.0..log(2)/K] - * m = n*K + j, m,n,j - signed integer, j in [0..K-1] - * values of 2^(j/K) are tabulated as T[j]. - * - * P(y) is a minimax polynomial approximation of expf(x)-1 - * on small interval [0.0..log(2)/K]. - * - * P(y) = P3*y*y*y*y + P2*y*y*y + P1*y*y + P0*y, calculated as - * z = y*y; P(y) = (P3*z + P1)*z + (P2*z + P0)*y - * - * Special cases: - * expf(NaN) = NaN - * expf(+INF) = +INF - * expf(-INF) = 0 - * expf(x) = 1 for subnormals - * for finite argument, only expf(0)=1 is exact - * expf(x) overflows if x>88.7228317260742190 - * expf(x) underflows if x<-103.972076416015620 - */ - - .text -ENTRY(__ieee754_expf) - /* Input: single precision x in %xmm0 */ - cvtss2sd %xmm0, %xmm1 /* Convert x to double precision */ - movd %xmm0, %ecx /* Copy x */ - movsd L(DP_KLN2)(%rip), %xmm2 /* DP K/log(2) */ - movsd L(DP_P2)(%rip), %xmm3 /* DP P2 */ - movl %ecx, %eax /* x */ - mulsd %xmm1, %xmm2 /* DP x*K/log(2) */ - andl $0x7fffffff, %ecx /* |x| */ - lea L(DP_T)(%rip), %rsi /* address of table T[j] */ - cmpl $0x42ad496b, %ecx /* |x|<125*log(2) ? */ - movsd L(DP_P3)(%rip), %xmm4 /* DP P3 */ - addsd L(DP_RS)(%rip), %xmm2 /* DP x*K/log(2)+RS */ - jae L(special_paths) - - /* Here if |x|<125*log(2) */ - cmpl $0x31800000, %ecx /* |x|<2^(-28) ? */ - jb L(small_arg) - - /* Main path: here if 2^(-28)<=|x|<125*log(2) */ - cvtsd2ss %xmm2, %xmm2 /* SP x*K/log(2)+RS */ - movd %xmm2, %eax /* bits of n*K+j with trash */ - subss L(SP_RS)(%rip), %xmm2 /* SP t=round(x*K/log(2)) */ - movl %eax, %edx /* n*K+j with trash */ - cvtss2sd %xmm2, %xmm2 /* DP t */ - andl $0x3f, %eax /* bits of j */ - mulsd L(DP_NLN2K)(%rip), %xmm2/* DP -t*log(2)/K */ - andl $0xffffffc0, %edx /* bits of n */ -#ifdef __AVX__ - vaddsd %xmm1, %xmm2, %xmm0 /* DP y=x-t*log(2)/K */ - vmulsd %xmm0, %xmm0, %xmm2 /* DP z=y*y */ -#else - addsd %xmm1, %xmm2 /* DP y=x-t*log(2)/K */ - movaps %xmm2, %xmm0 /* DP y */ - mulsd %xmm2, %xmm2 /* DP z=y*y */ -#endif - mulsd %xmm2, %xmm4 /* DP P3*z */ - addl $0x1fc0, %edx /* bits of n + SP exponent bias */ - mulsd %xmm2, %xmm3 /* DP P2*z */ - shll $17, %edx /* SP 2^n */ - addsd L(DP_P1)(%rip), %xmm4 /* DP P3*z+P1 */ - addsd L(DP_P0)(%rip), %xmm3 /* DP P2*z+P0 */ - movd %edx, %xmm1 /* SP 2^n */ - mulsd %xmm2, %xmm4 /* DP (P3*z+P1)*z */ - mulsd %xmm3, %xmm0 /* DP (P2*z+P0)*y */ - addsd %xmm4, %xmm0 /* DP P(y) */ - mulsd (%rsi,%rax,8), %xmm0 /* DP P(y)*T[j] */ - addsd (%rsi,%rax,8), %xmm0 /* DP T[j]*(P(y)+1) */ - cvtsd2ss %xmm0, %xmm0 /* SP T[j]*(P(y)+1) */ - mulss %xmm1, %xmm0 /* SP result=2^n*(T[j]*(P(y)+1)) */ - ret - - .p2align 4 -L(small_arg): - /* Here if 0<=|x|<2^(-28) */ - addss L(SP_ONE)(%rip), %xmm0 /* 1.0 + x */ - /* Return 1.0 with inexact raised, except for x==0 */ - ret - - .p2align 4 -L(special_paths): - /* Here if 125*log(2)<=|x| */ - shrl $31, %eax /* Get sign bit of x, and depending on it: */ - lea L(SP_RANGE)(%rip), %rdx /* load over/underflow bound */ - cmpl (%rdx,%rax,4), %ecx /* |x|<under/overflow bound ? */ - jbe L(near_under_or_overflow) - - /* Here if |x|>under/overflow bound */ - cmpl $0x7f800000, %ecx /* |x| is finite ? */ - jae L(arg_inf_or_nan) - - /* Here if |x|>under/overflow bound, and x is finite */ - testq %rax, %rax /* sign of x nonzero ? */ - je L(res_overflow) - - /* Here if -inf<x<underflow bound (x<0) */ - movss L(SP_SMALL)(%rip), %xmm0/* load small value 2^(-100) */ - mulss %xmm0, %xmm0 /* Return underflowed result (zero or subnormal) */ - ret - - .p2align 4 -L(res_overflow): - /* Here if overflow bound<x<inf (x>0) */ - movss L(SP_LARGE)(%rip), %xmm0/* load large value 2^100 */ - mulss %xmm0, %xmm0 /* Return overflowed result (Inf or max normal) */ - ret - - .p2align 4 -L(arg_inf_or_nan): - /* Here if |x| is Inf or NAN */ - jne L(arg_nan) /* |x| is Inf ? */ - - /* Here if |x| is Inf */ - lea L(SP_INF_0)(%rip), %rdx /* depending on sign of x: */ - movss (%rdx,%rax,4), %xmm0 /* return zero or Inf */ - ret - - .p2align 4 -L(arg_nan): - /* Here if |x| is NaN */ - addss %xmm0, %xmm0 /* Return x+x (raise invalid) */ - ret - - .p2align 4 -L(near_under_or_overflow): - /* Here if 125*log(2)<=|x|<under/overflow bound */ - cvtsd2ss %xmm2, %xmm2 /* SP x*K/log(2)+RS */ - movd %xmm2, %eax /* bits of n*K+j with trash */ - subss L(SP_RS)(%rip), %xmm2 /* SP t=round(x*K/log(2)) */ - movl %eax, %edx /* n*K+j with trash */ - cvtss2sd %xmm2, %xmm2 /* DP t */ - andl $0x3f, %eax /* bits of j */ - mulsd L(DP_NLN2K)(%rip), %xmm2/* DP -t*log(2)/K */ - andl $0xffffffc0, %edx /* bits of n */ -#ifdef __AVX__ - vaddsd %xmm1, %xmm2, %xmm0 /* DP y=x-t*log(2)/K */ - vmulsd %xmm0, %xmm0, %xmm2 /* DP z=y*y */ -#else - addsd %xmm1, %xmm2 /* DP y=x-t*log(2)/K */ - movaps %xmm2, %xmm0 /* DP y */ - mulsd %xmm2, %xmm2 /* DP z=y*y */ -#endif - mulsd %xmm2, %xmm4 /* DP P3*z */ - addl $0xffc0, %edx /* bits of n + DP exponent bias */ - mulsd %xmm2, %xmm3 /* DP P2*z */ - shlq $46, %rdx /* DP 2^n */ - addsd L(DP_P1)(%rip), %xmm4 /* DP P3*z+P1 */ - addsd L(DP_P0)(%rip), %xmm3 /* DP P2*z+P0 */ - movd %rdx, %xmm1 /* DP 2^n */ - mulsd %xmm2, %xmm4 /* DP (P3*z+P1)*z */ - mulsd %xmm3, %xmm0 /* DP (P2*z+P0)*y */ - addsd %xmm4, %xmm0 /* DP P(y) */ - mulsd (%rsi,%rax,8), %xmm0 /* DP P(y)*T[j] */ - addsd (%rsi,%rax,8), %xmm0 /* DP T[j]*(P(y)+1) */ - mulsd %xmm1, %xmm0 /* DP result=2^n*(T[j]*(P(y)+1)) */ - cvtsd2ss %xmm0, %xmm0 /* convert result to single precision */ - ret -END(__ieee754_expf) - - .section .rodata, "a" - .p2align 3 -L(DP_T): /* table of double precision values 2^(j/K) for j=[0..K-1] */ - .long 0x00000000, 0x3ff00000 - .long 0x3e778061, 0x3ff02c9a - .long 0xd3158574, 0x3ff059b0 - .long 0x18759bc8, 0x3ff08745 - .long 0x6cf9890f, 0x3ff0b558 - .long 0x32d3d1a2, 0x3ff0e3ec - .long 0xd0125b51, 0x3ff11301 - .long 0xaea92de0, 0x3ff1429a - .long 0x3c7d517b, 0x3ff172b8 - .long 0xeb6fcb75, 0x3ff1a35b - .long 0x3168b9aa, 0x3ff1d487 - .long 0x88628cd6, 0x3ff2063b - .long 0x6e756238, 0x3ff2387a - .long 0x65e27cdd, 0x3ff26b45 - .long 0xf51fdee1, 0x3ff29e9d - .long 0xa6e4030b, 0x3ff2d285 - .long 0x0a31b715, 0x3ff306fe - .long 0xb26416ff, 0x3ff33c08 - .long 0x373aa9cb, 0x3ff371a7 - .long 0x34e59ff7, 0x3ff3a7db - .long 0x4c123422, 0x3ff3dea6 - .long 0x21f72e2a, 0x3ff4160a - .long 0x6061892d, 0x3ff44e08 - .long 0xb5c13cd0, 0x3ff486a2 - .long 0xd5362a27, 0x3ff4bfda - .long 0x769d2ca7, 0x3ff4f9b2 - .long 0x569d4f82, 0x3ff5342b - .long 0x36b527da, 0x3ff56f47 - .long 0xdd485429, 0x3ff5ab07 - .long 0x15ad2148, 0x3ff5e76f - .long 0xb03a5585, 0x3ff6247e - .long 0x82552225, 0x3ff66238 - .long 0x667f3bcd, 0x3ff6a09e - .long 0x3c651a2f, 0x3ff6dfb2 - .long 0xe8ec5f74, 0x3ff71f75 - .long 0x564267c9, 0x3ff75feb - .long 0x73eb0187, 0x3ff7a114 - .long 0x36cf4e62, 0x3ff7e2f3 - .long 0x994cce13, 0x3ff82589 - .long 0x9b4492ed, 0x3ff868d9 - .long 0x422aa0db, 0x3ff8ace5 - .long 0x99157736, 0x3ff8f1ae - .long 0xb0cdc5e5, 0x3ff93737 - .long 0x9fde4e50, 0x3ff97d82 - .long 0x82a3f090, 0x3ff9c491 - .long 0x7b5de565, 0x3ffa0c66 - .long 0xb23e255d, 0x3ffa5503 - .long 0x5579fdbf, 0x3ffa9e6b - .long 0x995ad3ad, 0x3ffae89f - .long 0xb84f15fb, 0x3ffb33a2 - .long 0xf2fb5e47, 0x3ffb7f76 - .long 0x904bc1d2, 0x3ffbcc1e - .long 0xdd85529c, 0x3ffc199b - .long 0x2e57d14b, 0x3ffc67f1 - .long 0xdcef9069, 0x3ffcb720 - .long 0x4a07897c, 0x3ffd072d - .long 0xdcfba487, 0x3ffd5818 - .long 0x03db3285, 0x3ffda9e6 - .long 0x337b9b5f, 0x3ffdfc97 - .long 0xe78b3ff6, 0x3ffe502e - .long 0xa2a490da, 0x3ffea4af - .long 0xee615a27, 0x3ffefa1b - .long 0x5b6e4540, 0x3fff5076 - .long 0x819e90d8, 0x3fffa7c1 - .type L(DP_T), @object - ASM_SIZE_DIRECTIVE(L(DP_T)) - - .section .rodata.cst8,"aM",@progbits,8 - .p2align 3 -L(DP_KLN2): /* double precision K/log(2) */ - .long 0x652b82fe, 0x40571547 - .type L(DP_KLN2), @object - ASM_SIZE_DIRECTIVE(L(DP_KLN2)) - - .p2align 3 -L(DP_NLN2K): /* double precision -log(2)/K */ - .long 0xfefa39ef, 0xbf862e42 - .type L(DP_NLN2K), @object - ASM_SIZE_DIRECTIVE(L(DP_NLN2K)) - - .p2align 3 -L(DP_RS): /* double precision 2^23+2^22 */ - .long 0x00000000, 0x41680000 - .type L(DP_RS), @object - ASM_SIZE_DIRECTIVE(L(DP_RS)) - - .p2align 3 -L(DP_P3): /* double precision polynomial coefficient P3 */ - .long 0xeb78fa85, 0x3fa56420 - .type L(DP_P3), @object - ASM_SIZE_DIRECTIVE(L(DP_P3)) - - .p2align 3 -L(DP_P1): /* double precision polynomial coefficient P1 */ - .long 0x008d6118, 0x3fe00000 - .type L(DP_P1), @object - ASM_SIZE_DIRECTIVE(L(DP_P1)) - - .p2align 3 -L(DP_P2): /* double precision polynomial coefficient P2 */ - .long 0xda752d4f, 0x3fc55550 - .type L(DP_P2), @object - ASM_SIZE_DIRECTIVE(L(DP_P2)) - - .p2align 3 -L(DP_P0): /* double precision polynomial coefficient P0 */ - .long 0xffffe7c6, 0x3fefffff - .type L(DP_P0), @object - ASM_SIZE_DIRECTIVE(L(DP_P0)) - - .p2align 3 -L(SP_RANGE): /* single precision overflow/underflow bounds */ - .long 0x42b17217 /* if x>this bound, then result overflows */ - .long 0x42cff1b4 /* if x<this bound, then result underflows */ - .type L(SP_RANGE), @object - ASM_SIZE_DIRECTIVE(L(SP_RANGE)) - - .p2align 3 -L(SP_INF_0): - .long 0x7f800000 /* single precision Inf */ - .long 0 /* single precision zero */ - .type L(SP_INF_0), @object - ASM_SIZE_DIRECTIVE(L(SP_INF_0)) - - .section .rodata.cst4,"aM",@progbits,4 - .p2align 2 -L(SP_RS): /* single precision 2^23+2^22 */ - .long 0x4b400000 - .type L(SP_RS), @object - ASM_SIZE_DIRECTIVE(L(SP_RS)) - - .p2align 2 -L(SP_SMALL): /* single precision small value 2^(-100) */ - .long 0x0d800000 - .type L(SP_SMALL), @object - ASM_SIZE_DIRECTIVE(L(SP_SMALL)) - - .p2align 2 -L(SP_LARGE): /* single precision large value 2^100 */ - .long 0x71800000 - .type L(SP_LARGE), @object - ASM_SIZE_DIRECTIVE(L(SP_LARGE)) - - .p2align 2 -L(SP_ONE): /* single precision 1.0 */ - .long 0x3f800000 - .type L(SP_ONE), @object - ASM_SIZE_DIRECTIVE(L(SP_ONE)) - -strong_alias (__ieee754_expf, __expf_finite) |