1/* Function log2f vectorized with AVX2. 2 Copyright (C) 2021-2022 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/* 20 * ALGORITHM DESCRIPTION: 21 * 22 * Get short reciprocal approximation Rcp ~ 1/mantissa(x) 23 * R = Rcp*x - 1.0 24 * log2(x) = k - log2(Rcp) + poly_approximation(R) 25 * log2(Rcp) is tabulated 26 * 27 * 28 */ 29 30/* Offsets for data table __svml_slog2_data_internal 31 */ 32#define MinNorm 0 33#define MaxNorm 32 34#define iBrkValue 64 35#define iOffExpoMask 96 36#define One 128 37#define sPoly 160 38 39#include <sysdep.h> 40 41 .section .text.avx2, "ax", @progbits 42ENTRY(_ZGVdN8v_log2f_avx2) 43 pushq %rbp 44 cfi_def_cfa_offset(16) 45 movq %rsp, %rbp 46 cfi_def_cfa(6, 16) 47 cfi_offset(6, -16) 48 andq $-32, %rsp 49 subq $96, %rsp 50 51 /* reduction: compute r, n */ 52 vmovups iBrkValue+__svml_slog2_data_internal(%rip), %ymm4 53 vmovups sPoly+64+__svml_slog2_data_internal(%rip), %ymm9 54 vmovups sPoly+128+__svml_slog2_data_internal(%rip), %ymm10 55 vmovups sPoly+192+__svml_slog2_data_internal(%rip), %ymm12 56 vpsubd %ymm4, %ymm0, %ymm1 57 vcmplt_oqps MinNorm+__svml_slog2_data_internal(%rip), %ymm0, %ymm5 58 vcmpnle_uqps MaxNorm+__svml_slog2_data_internal(%rip), %ymm0, %ymm6 59 vpand iOffExpoMask+__svml_slog2_data_internal(%rip), %ymm1, %ymm3 60 vpsrad $23, %ymm1, %ymm2 61 vmovups sPoly+__svml_slog2_data_internal(%rip), %ymm1 62 vpaddd %ymm4, %ymm3, %ymm8 63 vcvtdq2ps %ymm2, %ymm14 64 vsubps One+__svml_slog2_data_internal(%rip), %ymm8, %ymm13 65 vfmadd213ps sPoly+32+__svml_slog2_data_internal(%rip), %ymm13, %ymm1 66 vfmadd213ps sPoly+96+__svml_slog2_data_internal(%rip), %ymm13, %ymm9 67 vmulps %ymm13, %ymm13, %ymm11 68 vfmadd213ps sPoly+160+__svml_slog2_data_internal(%rip), %ymm13, %ymm10 69 vfmadd213ps sPoly+224+__svml_slog2_data_internal(%rip), %ymm13, %ymm12 70 vfmadd213ps %ymm9, %ymm11, %ymm1 71 vfmadd213ps %ymm10, %ymm11, %ymm1 72 vfmadd213ps %ymm12, %ymm11, %ymm1 73 vfmadd213ps sPoly+256+__svml_slog2_data_internal(%rip), %ymm13, %ymm1 74 vorps %ymm6, %ymm5, %ymm7 75 76 /* combine and get argument value range mask */ 77 vmovmskps %ymm7, %edx 78 vfmadd213ps %ymm14, %ymm13, %ymm1 79 testl %edx, %edx 80 81 /* Go to special inputs processing branch */ 82 jne L(SPECIAL_VALUES_BRANCH) 83 # LOE rbx r12 r13 r14 r15 edx ymm0 ymm1 84 85 /* Restore registers 86 * and exit the function 87 */ 88 89L(EXIT): 90 vmovaps %ymm1, %ymm0 91 movq %rbp, %rsp 92 popq %rbp 93 cfi_def_cfa(7, 8) 94 cfi_restore(6) 95 ret 96 cfi_def_cfa(6, 16) 97 cfi_offset(6, -16) 98 99 /* Branch to process 100 * special inputs 101 */ 102 103L(SPECIAL_VALUES_BRANCH): 104 vmovups %ymm0, 32(%rsp) 105 vmovups %ymm1, 64(%rsp) 106 # LOE rbx r12 r13 r14 r15 edx ymm1 107 108 xorl %eax, %eax 109 # LOE rbx r12 r13 r14 r15 eax edx 110 111 vzeroupper 112 movq %r12, 16(%rsp) 113 /* DW_CFA_expression: r12 (r12) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -32; DW_OP_and; DW_OP_const4s: -80; DW_OP_plus) */ 114 .cfi_escape 0x10, 0x0c, 0x0e, 0x38, 0x1c, 0x0d, 0xe0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0xb0, 0xff, 0xff, 0xff, 0x22 115 movl %eax, %r12d 116 movq %r13, 8(%rsp) 117 /* DW_CFA_expression: r13 (r13) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -32; DW_OP_and; DW_OP_const4s: -88; DW_OP_plus) */ 118 .cfi_escape 0x10, 0x0d, 0x0e, 0x38, 0x1c, 0x0d, 0xe0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0xa8, 0xff, 0xff, 0xff, 0x22 119 movl %edx, %r13d 120 movq %r14, (%rsp) 121 /* DW_CFA_expression: r14 (r14) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -32; DW_OP_and; DW_OP_const4s: -96; DW_OP_plus) */ 122 .cfi_escape 0x10, 0x0e, 0x0e, 0x38, 0x1c, 0x0d, 0xe0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0xa0, 0xff, 0xff, 0xff, 0x22 123 # LOE rbx r15 r12d r13d 124 125 /* Range mask 126 * bits check 127 */ 128 129L(RANGEMASK_CHECK): 130 btl %r12d, %r13d 131 132 /* Call scalar math function */ 133 jc L(SCALAR_MATH_CALL) 134 # LOE rbx r15 r12d r13d 135 136 /* Special inputs 137 * processing loop 138 */ 139 140L(SPECIAL_VALUES_LOOP): 141 incl %r12d 142 cmpl $8, %r12d 143 144 /* Check bits in range mask */ 145 jl L(RANGEMASK_CHECK) 146 # LOE rbx r15 r12d r13d 147 148 movq 16(%rsp), %r12 149 cfi_restore(12) 150 movq 8(%rsp), %r13 151 cfi_restore(13) 152 movq (%rsp), %r14 153 cfi_restore(14) 154 vmovups 64(%rsp), %ymm1 155 156 /* Go to exit */ 157 jmp L(EXIT) 158 /* DW_CFA_expression: r12 (r12) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -32; DW_OP_and; DW_OP_const4s: -80; DW_OP_plus) */ 159 .cfi_escape 0x10, 0x0c, 0x0e, 0x38, 0x1c, 0x0d, 0xe0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0xb0, 0xff, 0xff, 0xff, 0x22 160 /* DW_CFA_expression: r13 (r13) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -32; DW_OP_and; DW_OP_const4s: -88; DW_OP_plus) */ 161 .cfi_escape 0x10, 0x0d, 0x0e, 0x38, 0x1c, 0x0d, 0xe0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0xa8, 0xff, 0xff, 0xff, 0x22 162 /* DW_CFA_expression: r14 (r14) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -32; DW_OP_and; DW_OP_const4s: -96; DW_OP_plus) */ 163 .cfi_escape 0x10, 0x0e, 0x0e, 0x38, 0x1c, 0x0d, 0xe0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0xa0, 0xff, 0xff, 0xff, 0x22 164 # LOE rbx r12 r13 r14 r15 ymm1 165 166 /* Scalar math fucntion call 167 * to process special input 168 */ 169 170L(SCALAR_MATH_CALL): 171 movl %r12d, %r14d 172 vmovss 32(%rsp, %r14, 4), %xmm0 173 call log2f@PLT 174 # LOE rbx r14 r15 r12d r13d xmm0 175 176 vmovss %xmm0, 64(%rsp, %r14, 4) 177 178 /* Process special inputs in loop */ 179 jmp L(SPECIAL_VALUES_LOOP) 180 # LOE rbx r15 r12d r13d 181END(_ZGVdN8v_log2f_avx2) 182 183 .section .rodata, "a" 184 .align 32 185 186#ifdef __svml_slog2_data_internal_typedef 187typedef unsigned int VUINT32; 188typedef struct { 189 __declspec(align(32)) VUINT32 MinNorm[8][1]; 190 __declspec(align(32)) VUINT32 MaxNorm[8][1]; 191 __declspec(align(32)) VUINT32 iBrkValue[8][1]; 192 __declspec(align(32)) VUINT32 iOffExpoMask[8][1]; 193 __declspec(align(32)) VUINT32 One[8][1]; 194 __declspec(align(32)) VUINT32 sPoly[9][8][1]; 195} __svml_slog2_data_internal; 196#endif 197__svml_slog2_data_internal: 198 /* MinNorm */ 199 .long 0x00800000, 0x00800000, 0x00800000, 0x00800000, 0x00800000, 0x00800000, 0x00800000, 0x00800000 200 /* MaxNorm */ 201 .align 32 202 .long 0x7f7fffff, 0x7f7fffff, 0x7f7fffff, 0x7f7fffff, 0x7f7fffff, 0x7f7fffff, 0x7f7fffff, 0x7f7fffff 203 /* iBrkValue = SP 2/3 */ 204 .align 32 205 .long 0x3f2aaaab, 0x3f2aaaab, 0x3f2aaaab, 0x3f2aaaab, 0x3f2aaaab, 0x3f2aaaab, 0x3f2aaaab, 0x3f2aaaab 206 /* iOffExpoMask = SP significand mask */ 207 .align 32 208 .long 0x007fffff, 0x007fffff, 0x007fffff, 0x007fffff, 0x007fffff, 0x007fffff, 0x007fffff, 0x007fffff 209 /* sOne = SP 1.0 */ 210 .align 32 211 .long 0x3f800000, 0x3f800000, 0x3f800000, 0x3f800000, 0x3f800000, 0x3f800000, 0x3f800000, 0x3f800000 212 /* spoly[9] */ 213 .align 32 214 .long 0x3e554012, 0x3e554012, 0x3e554012, 0x3e554012, 0x3e554012, 0x3e554012, 0x3e554012, 0x3e554012 /* coeff9 */ 215 .long 0xbe638E14, 0xbe638E14, 0xbe638E14, 0xbe638E14, 0xbe638E14, 0xbe638E14, 0xbe638E14, 0xbe638E14 /* coeff8 */ 216 .long 0x3e4D660B, 0x3e4D660B, 0x3e4D660B, 0x3e4D660B, 0x3e4D660B, 0x3e4D660B, 0x3e4D660B, 0x3e4D660B /* coeff7 */ 217 .long 0xbe727824, 0xbe727824, 0xbe727824, 0xbe727824, 0xbe727824, 0xbe727824, 0xbe727824, 0xbe727824 /* coeff6 */ 218 .long 0x3e93DD07, 0x3e93DD07, 0x3e93DD07, 0x3e93DD07, 0x3e93DD07, 0x3e93DD07, 0x3e93DD07, 0x3e93DD07 /* coeff5 */ 219 .long 0xbeB8B969, 0xbeB8B969, 0xbeB8B969, 0xbeB8B969, 0xbeB8B969, 0xbeB8B969, 0xbeB8B969, 0xbeB8B969 /* coeff4 */ 220 .long 0x3eF637C0, 0x3eF637C0, 0x3eF637C0, 0x3eF637C0, 0x3eF637C0, 0x3eF637C0, 0x3eF637C0, 0x3eF637C0 /* coeff3 */ 221 .long 0xbf38AA2B, 0xbf38AA2B, 0xbf38AA2B, 0xbf38AA2B, 0xbf38AA2B, 0xbf38AA2B, 0xbf38AA2B, 0xbf38AA2B /* coeff2 */ 222 .long 0x3fB8AA3B, 0x3fB8AA3B, 0x3fB8AA3B, 0x3fB8AA3B, 0x3fB8AA3B, 0x3fB8AA3B, 0x3fB8AA3B, 0x3fB8AA3B /* coeff1 */ 223 .align 32 224 .type __svml_slog2_data_internal, @object 225 .size __svml_slog2_data_internal, .-__svml_slog2_data_internal 226