1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
/* Function logf vectorized with SSE4.
Copyright (C) 2014-2019 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
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include "svml_s_logf_data.h"
.text
ENTRY (_ZGVbN4v_logf_sse4)
/*
ALGORITHM DESCRIPTION:
log(x) = exponent_x*log(2) + log(mantissa_x), if mantissa_x<4/3
log(x) = (exponent_x+1)*log(2) + log(0.5*mantissa_x), if mantissa_x>4/3
R = mantissa_x - 1, if mantissa_x<4/3
R = 0.5*mantissa_x - 1, if mantissa_x>4/3
|R|< 1/3
log(1+R) is approximated as a polynomial: degree 9 for 1-ulp,
degree 7 for 4-ulp, degree 3 for half-precision. */
pushq %rbp
cfi_adjust_cfa_offset (8)
cfi_rel_offset (%rbp, 0)
movq %rsp, %rbp
cfi_def_cfa_register (%rbp)
andq $-64, %rsp
subq $320, %rsp
/* reduction: compute r,n */
movaps %xmm0, %xmm2
/* check for working range,
set special argument mask (denormals/zero/Inf/NaN) */
movq __svml_slog_data@GOTPCREL(%rip), %rax
movdqu _iHiDelta(%rax), %xmm1
movdqu _iLoRange(%rax), %xmm4
paddd %xmm0, %xmm1
movdqu _iBrkValue(%rax), %xmm3
pcmpgtd %xmm1, %xmm4
movdqu _iOffExpoMask(%rax), %xmm1
psubd %xmm3, %xmm2
pand %xmm2, %xmm1
/* exponent_x (mantissa_x<4/3) or exponent_x+1 (mantissa_x>4/3) */
psrad $23, %xmm2
paddd %xmm3, %xmm1
movups _sPoly_7(%rax), %xmm5
/* mantissa_x (mantissa_x<4/3), or 0.5*mantissa_x (mantissa_x>4/3) */
cvtdq2ps %xmm2, %xmm6
/* reduced argument R */
subps _sOne(%rax), %xmm1
movmskps %xmm4, %ecx
/* final reconstruction:
add exponent_value*log2 to polynomial result */
mulps _sLn2(%rax), %xmm6
/* polynomial evaluation starts here */
mulps %xmm1, %xmm5
addps _sPoly_6(%rax), %xmm5
mulps %xmm1, %xmm5
addps _sPoly_5(%rax), %xmm5
mulps %xmm1, %xmm5
addps _sPoly_4(%rax), %xmm5
mulps %xmm1, %xmm5
addps _sPoly_3(%rax), %xmm5
mulps %xmm1, %xmm5
addps _sPoly_2(%rax), %xmm5
mulps %xmm1, %xmm5
addps _sPoly_1(%rax), %xmm5
mulps %xmm1, %xmm5
/* polynomial evaluation end */
mulps %xmm1, %xmm5
addps %xmm5, %xmm1
addps %xmm6, %xmm1
testl %ecx, %ecx
jne .LBL_1_3
.LBL_1_2:
cfi_remember_state
movdqa %xmm1, %xmm0
movq %rbp, %rsp
cfi_def_cfa_register (%rsp)
popq %rbp
cfi_adjust_cfa_offset (-8)
cfi_restore (%rbp)
ret
.LBL_1_3:
cfi_restore_state
movups %xmm0, 192(%rsp)
movups %xmm1, 256(%rsp)
je .LBL_1_2
xorb %dl, %dl
xorl %eax, %eax
movups %xmm8, 112(%rsp)
movups %xmm9, 96(%rsp)
movups %xmm10, 80(%rsp)
movups %xmm11, 64(%rsp)
movups %xmm12, 48(%rsp)
movups %xmm13, 32(%rsp)
movups %xmm14, 16(%rsp)
movups %xmm15, (%rsp)
movq %rsi, 136(%rsp)
movq %rdi, 128(%rsp)
movq %r12, 168(%rsp)
cfi_offset_rel_rsp (12, 168)
movb %dl, %r12b
movq %r13, 160(%rsp)
cfi_offset_rel_rsp (13, 160)
movl %ecx, %r13d
movq %r14, 152(%rsp)
cfi_offset_rel_rsp (14, 152)
movl %eax, %r14d
movq %r15, 144(%rsp)
cfi_offset_rel_rsp (15, 144)
cfi_remember_state
.LBL_1_6:
btl %r14d, %r13d
jc .LBL_1_12
.LBL_1_7:
lea 1(%r14), %esi
btl %esi, %r13d
jc .LBL_1_10
.LBL_1_8:
incb %r12b
addl $2, %r14d
cmpb $16, %r12b
jb .LBL_1_6
movups 112(%rsp), %xmm8
movups 96(%rsp), %xmm9
movups 80(%rsp), %xmm10
movups 64(%rsp), %xmm11
movups 48(%rsp), %xmm12
movups 32(%rsp), %xmm13
movups 16(%rsp), %xmm14
movups (%rsp), %xmm15
movq 136(%rsp), %rsi
movq 128(%rsp), %rdi
movq 168(%rsp), %r12
cfi_restore (%r12)
movq 160(%rsp), %r13
cfi_restore (%r13)
movq 152(%rsp), %r14
cfi_restore (%r14)
movq 144(%rsp), %r15
cfi_restore (%r15)
movups 256(%rsp), %xmm1
jmp .LBL_1_2
.LBL_1_10:
cfi_restore_state
movzbl %r12b, %r15d
movss 196(%rsp,%r15,8), %xmm0
call JUMPTARGET(logf)
movss %xmm0, 260(%rsp,%r15,8)
jmp .LBL_1_8
.LBL_1_12:
movzbl %r12b, %r15d
movss 192(%rsp,%r15,8), %xmm0
call JUMPTARGET(logf)
movss %xmm0, 256(%rsp,%r15,8)
jmp .LBL_1_7
END (_ZGVbN4v_logf_sse4)
|