+++ /dev/null
-/* SSE2 version of __ieee754_expf and __expf_finite
- Copyright (C) 2012-2017 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 <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:
- * __ieee754_expf_sse2(NaN) = NaN
- * __ieee754_expf_sse2(+INF) = +INF
- * __ieee754_expf_sse2(-INF) = 0
- * __ieee754_expf_sse2(x) = 1 for subnormals
- * for finite argument, only __ieee754_expf_sse2(0)=1 is exact
- * __ieee754_expf_sse2(x) overflows if x>700
- * __ieee754_expf_sse2(x) underflows if x<-700
- *
- * Note:
- * For |x|<700, __ieee754_expf_sse2 computes result in double precision,
- * with accuracy a bit more than needed for expf, and does not round it
- * to single precision.
- */
-
-
-#ifdef PIC
-# define MO1(symbol) L(symbol)##@GOTOFF(%edx)
-# define MO2(symbol,reg2,_scale) L(symbol)##@GOTOFF(%edx,reg2,_scale)
-#else
-# define MO1(symbol) L(symbol)
-# define MO2(symbol,reg2,_scale) L(symbol)(,reg2,_scale)
-#endif
-
- .text
-ENTRY(__ieee754_expf_sse2)
- /* Input: single precision x on stack at address 4(%esp) */
-
-#ifdef PIC
- LOAD_PIC_REG(dx)
-#endif
-
- cvtss2sd 4(%esp), %xmm1 /* Convert x to double precision */
- mov 4(%esp), %ecx /* Copy x */
- movsd MO1(DP_KLN2), %xmm2 /* DP K/log(2) */
- movsd MO1(DP_P2), %xmm3 /* DP P2 */
- movl %ecx, %eax /* x */
- mulsd %xmm1, %xmm2 /* DP x*K/log(2) */
- andl $0x7fffffff, %ecx /* |x| */
- cmpl $0x442f0000, %ecx /* |x|<700 ? */
- movsd MO1(DP_P3), %xmm4 /* DP P3 */
- addsd MO1(DP_RS), %xmm2 /* DP x*K/log(2)+RS */
- jae L(special_paths)
-
- /* Here if |x|<700 */
- cmpl $0x31800000, %ecx /* |x|<2^(-28) ? */
- jb L(small_arg)
-
- /* Main path: here if 2^(-28)<=|x|<700 */
- cvtsd2ss %xmm2, %xmm2 /* SP x*K/log(2)+RS */
- movd %xmm2, %eax /* bits of n*K+j with trash */
- subss MO1(SP_RS), %xmm2 /* SP t=round(x*K/log(2)) */
- movl %eax, %ecx /* n*K+j with trash */
- cvtss2sd %xmm2, %xmm2 /* DP t */
- andl $0x3f, %eax /* bits of j */
- mulsd MO1(DP_NLN2K), %xmm2 /* DP -t*log(2)/K */
- andl $0xffffffc0, %ecx /* 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, %ecx /* bits of n + DP exponent bias */
- mulsd %xmm2, %xmm3 /* DP P2*z */
- shrl $2, %ecx /* High 2 bytes of DP 2^n */
- pxor %xmm1, %xmm1 /* clear %xmm1 */
- addsd MO1(DP_P1), %xmm4 /* DP P3*z+P1 */
- addsd MO1(DP_P0), %xmm3 /* DP P2*z+P0 */
- pinsrw $3, %ecx, %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 MO2(DP_T,%eax,8), %xmm0 /* DP P(y)*T[j] */
- addsd MO2(DP_T,%eax,8), %xmm0 /* DP T[j]*(P(y)+1) */
- mulsd %xmm1, %xmm0 /* DP result=2^n*(T[j]*(P(y)+1)) */
- cvtsd2ss %xmm0, %xmm1
-
- lea -4(%esp), %esp /* Borrow 4 bytes of stack frame */
- movss %xmm1, 0(%esp) /* Move result from sse... */
- flds 0(%esp) /* ...to FPU. */
- lea 4(%esp), %esp /* Return back 4 bytes of stack frame */
- ret
-
- .p2align 4
-L(small_arg):
- /* Here if 0<=|x|<2^(-28) */
- movss 4(%esp), %xmm0 /* load x */
- addss MO1(SP_ONE), %xmm0 /* 1.0 + x */
- /* Return 1.0 with inexact raised, except for x==0 */
- jmp L(epilogue)
-
- .p2align 4
-L(special_paths):
- /* Here if x is NaN, or Inf, or finite |x|>=700 */
- movss 4(%esp), %xmm0 /* load x */
-
- cmpl $0x7f800000, %ecx /* |x| is finite ? */
- jae L(arg_inf_or_nan)
-
- /* Here if finite |x|>=700 */
- testl $0x80000000, %eax /* sign of x nonzero ? */
- je L(res_overflow)
-
- /* Here if finite x<=-700 */
- movss MO1(SP_SMALL), %xmm0 /* load small value 2^(-100) */
- mulss %xmm0, %xmm0 /* Return underflowed result (zero or subnormal) */
- jmp L(epilogue)
-
- .p2align 4
-L(res_overflow):
- /* Here if finite x>=700 */
- movss MO1(SP_LARGE), %xmm0 /* load large value 2^100 */
- mulss %xmm0, %xmm0 /* Return overflowed result (Inf or max normal) */
- jmp L(epilogue)
-
- .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 */
- shrl $31, %eax /* Get sign bit of x */
- movss MO2(SP_INF_0,%eax,4), %xmm0/* return zero or Inf, depending on sign of x */
- jmp L(epilogue)
-
- .p2align 4
-L(arg_nan):
- /* Here if |x| is NaN */
- addss %xmm0, %xmm0 /* Return x+x (raise invalid) */
-
- .p2align 4
-L(epilogue):
- lea -4(%esp), %esp /* Borrow 4 bytes of stack frame */
- movss %xmm0, 0(%esp) /* Move result from sse... */
- flds 0(%esp) /* ...to FPU. */
- lea 4(%esp), %esp /* Return back 4 bytes of stack frame */
- ret
-END(__ieee754_expf_sse2)
-
- .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 2
-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_sse2, __expf_finite_sse2)
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