| dnl Intel P5 mpn_hamdist -- mpn hamming distance. |
| |
| dnl Copyright 2001, 2002, 2014, 2015 Free Software Foundation, Inc. |
| |
| dnl This file is part of the GNU MP Library. |
| dnl |
| dnl The GNU MP Library is free software; you can redistribute it and/or modify |
| dnl it under the terms of either: |
| dnl |
| dnl * the GNU Lesser General Public License as published by the Free |
| dnl Software Foundation; either version 3 of the License, or (at your |
| dnl option) any later version. |
| dnl |
| dnl or |
| dnl |
| dnl * the GNU General Public License as published by the Free Software |
| dnl Foundation; either version 2 of the License, or (at your option) any |
| dnl later version. |
| dnl |
| dnl or both in parallel, as here. |
| dnl |
| dnl The GNU MP Library is distributed in the hope that it will be useful, but |
| dnl WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
| dnl or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| dnl for more details. |
| dnl |
| dnl You should have received copies of the GNU General Public License and the |
| dnl GNU Lesser General Public License along with the GNU MP Library. If not, |
| dnl see https://www.gnu.org/licenses/. |
| |
| include(`../config.m4') |
| |
| |
| C P5: 14.0 cycles/limb |
| |
| |
| C unsigned long mpn_hamdist (mp_srcptr src1, mp_srcptr src2, mp_size_t size); |
| C |
| C It might be possible to shave 1 cycle from the loop, and hence 2 |
| C cycles/limb. The xorb is taking 2 cycles, but a separate load and xor |
| C would be 1, if the right schedule could be found (not found so far). |
| C Wanting to avoid potential cache bank clashes makes it tricky. |
| |
| C The slightly strange quoting here helps the renaming done by tune/many.pl. |
| deflit(TABLE_NAME, |
| m4_assert_defined(`GSYM_PREFIX') |
| GSYM_PREFIX`'mpn_popcount``'_table') |
| |
| C FIXME: referencing popcount.asm's table is incorrect as it hurt incremental |
| C linking. |
| |
| defframe(PARAM_SIZE,12) |
| defframe(PARAM_SRC2, 8) |
| defframe(PARAM_SRC1, 4) |
| |
| TEXT |
| ALIGN(8) |
| |
| PROLOGUE(mpn_hamdist) |
| deflit(`FRAME',0) |
| |
| movl PARAM_SIZE, %ecx |
| pushl %esi FRAME_pushl() |
| |
| shll %ecx C size in byte pairs |
| pushl %edi FRAME_pushl() |
| |
| ifdef(`PIC',` |
| pushl %ebx FRAME_pushl() |
| pushl %ebp FRAME_pushl() |
| ifdef(`DARWIN',` |
| movl PARAM_SRC1, %esi |
| movl PARAM_SRC2, %edi |
| LEA( TABLE_NAME, %ebp) |
| xorl %ebx, %ebx C byte |
| xorl %edx, %edx C byte |
| xorl %eax, %eax C total |
| ',` |
| call L(here) FRAME_pushl() |
| L(here): |
| movl PARAM_SRC1, %esi |
| popl %ebp FRAME_popl() |
| |
| movl PARAM_SRC2, %edi |
| addl $_GLOBAL_OFFSET_TABLE_+[.-L(here)], %ebp |
| |
| xorl %ebx, %ebx C byte |
| xorl %edx, %edx C byte |
| |
| movl TABLE_NAME@GOT(%ebp), %ebp |
| xorl %eax, %eax C total |
| ') |
| define(TABLE,`(%ebp,$1)') |
| ',` |
| dnl non-PIC |
| movl PARAM_SRC1, %esi |
| movl PARAM_SRC2, %edi |
| |
| xorl %eax, %eax C total |
| pushl %ebx FRAME_pushl() |
| |
| xorl %edx, %edx C byte |
| xorl %ebx, %ebx C byte |
| |
| define(TABLE,`TABLE_NAME($1)') |
| ') |
| |
| |
| C The nop after the xorb seems necessary. Although a movb might be |
| C expected to go down the V pipe in the second cycle of the xorb, it |
| C doesn't and costs an extra 2 cycles. |
| L(top): |
| C eax total |
| C ebx byte |
| C ecx counter, 2*size to 2 |
| C edx byte |
| C esi src1 |
| C edi src2 |
| C ebp [PIC] table |
| |
| addl %ebx, %eax |
| movb -1(%esi,%ecx,2), %bl |
| |
| addl %edx, %eax |
| movb -1(%edi,%ecx,2), %dl |
| |
| xorb %dl, %bl |
| movb -2(%esi,%ecx,2), %dl |
| |
| xorb -2(%edi,%ecx,2), %dl |
| nop |
| |
| movb TABLE(%ebx), %bl |
| decl %ecx |
| |
| movb TABLE(%edx), %dl |
| jnz L(top) |
| |
| |
| ifdef(`PIC',` |
| popl %ebp |
| ') |
| addl %ebx, %eax |
| popl %ebx |
| |
| addl %edx, %eax |
| popl %edi |
| |
| popl %esi |
| |
| ret |
| |
| EPILOGUE() |
| ASM_END() |
