1/* Function logf vectorized with AVX2.
2   Copyright (C) 2014-2022 Free Software Foundation, Inc.
3   This file is part of the GNU C Library.
4
5   The GNU C Library is free software; you can redistribute it and/or
6   modify it under the terms of the GNU Lesser General Public
7   License as published by the Free Software Foundation; either
8   version 2.1 of the License, or (at your option) any later version.
9
10   The GNU C Library is distributed in the hope that it will be useful,
11   but WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13   Lesser General Public License for more details.
14
15   You should have received a copy of the GNU Lesser General Public
16   License along with the GNU C Library; if not, see
17   <https://www.gnu.org/licenses/>.  */
18
19#include <sysdep.h>
20#include "svml_s_logf_data.h"
21
22	.text
23ENTRY(_ZGVdN8v_logf_avx2)
24/*
25   ALGORITHM DESCRIPTION:
26
27    log(x) = exponent_x*log(2) + log(mantissa_x),         if mantissa_x<4/3
28    log(x) = (exponent_x+1)*log(2) + log(0.5*mantissa_x), if mantissa_x>4/3
29
30    R = mantissa_x - 1,     if mantissa_x<4/3
31    R = 0.5*mantissa_x - 1, if mantissa_x>4/3
32    |R|< 1/3
33
34    log(1+R) is approximated as a polynomial: degree 9 for 1-ulp,
35    degree 7 for 4-ulp, degree 3 for half-precision.  */
36
37        pushq     %rbp
38        cfi_adjust_cfa_offset (8)
39        cfi_rel_offset (%rbp, 0)
40        movq      %rsp, %rbp
41        cfi_def_cfa_register (%rbp)
42        andq      $-64, %rsp
43        subq      $448, %rsp
44        movq      __svml_slog_data@GOTPCREL(%rip), %rax
45        vmovaps   %ymm0, %ymm2
46        vmovups _iBrkValue(%rax), %ymm6
47        vmovups _iLoRange(%rax), %ymm1
48/* check for working range,
49   set special argument mask (denormals/zero/Inf/NaN) */
50        vpaddd _iHiDelta(%rax), %ymm2, %ymm7
51
52/* reduction: compute r,n */
53        vpsubd    %ymm6, %ymm2, %ymm4
54
55/* exponent_x (mantissa_x<4/3) or exponent_x+1 (mantissa_x>4/3) */
56        vpsrad    $23, %ymm4, %ymm3
57        vpand _iOffExpoMask(%rax), %ymm4, %ymm5
58        vmovups _sPoly_7(%rax), %ymm4
59        vcvtdq2ps %ymm3, %ymm0
60
61/* mantissa_x (mantissa_x<4/3), or 0.5*mantissa_x (mantissa_x>4/3) */
62        vpaddd    %ymm6, %ymm5, %ymm3
63
64/* reduced argument R */
65        vsubps _sOne(%rax), %ymm3, %ymm5
66
67/* polynomial evaluation starts here */
68        vfmadd213ps _sPoly_6(%rax), %ymm5, %ymm4
69        vfmadd213ps _sPoly_5(%rax), %ymm5, %ymm4
70        vfmadd213ps _sPoly_4(%rax), %ymm5, %ymm4
71        vfmadd213ps _sPoly_3(%rax), %ymm5, %ymm4
72        vfmadd213ps _sPoly_2(%rax), %ymm5, %ymm4
73        vfmadd213ps _sPoly_1(%rax), %ymm5, %ymm4
74        vmulps    %ymm5, %ymm4, %ymm6
75
76/* polynomial evaluation end */
77        vfmadd213ps %ymm5, %ymm5, %ymm6
78        vpcmpgtd  %ymm7, %ymm1, %ymm1
79        vmovmskps %ymm1, %ecx
80
81/* final reconstruction:
82   add exponent_value*log2 to polynomial result */
83        vfmadd132ps _sLn2(%rax), %ymm6, %ymm0
84        testl     %ecx, %ecx
85        jne       .LBL_1_3
86
87.LBL_1_2:
88        cfi_remember_state
89        movq      %rbp, %rsp
90        cfi_def_cfa_register (%rsp)
91        popq      %rbp
92        cfi_adjust_cfa_offset (-8)
93        cfi_restore (%rbp)
94        ret
95
96.LBL_1_3:
97        cfi_restore_state
98        vmovups   %ymm2, 320(%rsp)
99        vmovups   %ymm0, 384(%rsp)
100        je        .LBL_1_2
101
102        xorb      %dl, %dl
103        xorl      %eax, %eax
104        vmovups   %ymm8, 224(%rsp)
105        vmovups   %ymm9, 192(%rsp)
106        vmovups   %ymm10, 160(%rsp)
107        vmovups   %ymm11, 128(%rsp)
108        vmovups   %ymm12, 96(%rsp)
109        vmovups   %ymm13, 64(%rsp)
110        vmovups   %ymm14, 32(%rsp)
111        vmovups   %ymm15, (%rsp)
112        movq      %rsi, 264(%rsp)
113        movq      %rdi, 256(%rsp)
114        movq      %r12, 296(%rsp)
115        cfi_offset_rel_rsp (12, 296)
116        movb      %dl, %r12b
117        movq      %r13, 288(%rsp)
118        cfi_offset_rel_rsp (13, 288)
119        movl      %ecx, %r13d
120        movq      %r14, 280(%rsp)
121        cfi_offset_rel_rsp (14, 280)
122        movl      %eax, %r14d
123        movq      %r15, 272(%rsp)
124        cfi_offset_rel_rsp (15, 272)
125        cfi_remember_state
126
127.LBL_1_6:
128        btl       %r14d, %r13d
129        jc        .LBL_1_12
130
131.LBL_1_7:
132        lea       1(%r14), %esi
133        btl       %esi, %r13d
134        jc        .LBL_1_10
135
136.LBL_1_8:
137        incb      %r12b
138        addl      $2, %r14d
139        cmpb      $16, %r12b
140        jb        .LBL_1_6
141
142        vmovups   224(%rsp), %ymm8
143        vmovups   192(%rsp), %ymm9
144        vmovups   160(%rsp), %ymm10
145        vmovups   128(%rsp), %ymm11
146        vmovups   96(%rsp), %ymm12
147        vmovups   64(%rsp), %ymm13
148        vmovups   32(%rsp), %ymm14
149        vmovups   (%rsp), %ymm15
150        vmovups   384(%rsp), %ymm0
151        movq      264(%rsp), %rsi
152        movq      256(%rsp), %rdi
153        movq      296(%rsp), %r12
154        cfi_restore (%r12)
155        movq      288(%rsp), %r13
156        cfi_restore (%r13)
157        movq      280(%rsp), %r14
158        cfi_restore (%r14)
159        movq      272(%rsp), %r15
160        cfi_restore (%r15)
161        jmp       .LBL_1_2
162
163.LBL_1_10:
164        cfi_restore_state
165        movzbl    %r12b, %r15d
166        vmovss    324(%rsp,%r15,8), %xmm0
167        vzeroupper
168
169        call      JUMPTARGET(logf)
170
171        vmovss    %xmm0, 388(%rsp,%r15,8)
172        jmp       .LBL_1_8
173
174.LBL_1_12:
175        movzbl    %r12b, %r15d
176        vmovss    320(%rsp,%r15,8), %xmm0
177        vzeroupper
178
179        call      JUMPTARGET(logf)
180
181        vmovss    %xmm0, 384(%rsp,%r15,8)
182        jmp       .LBL_1_7
183
184END(_ZGVdN8v_logf_avx2)
185