| dnl Intel P5 mpn_popcount -- mpn bit population count. |
| |
| dnl Copyright 2001, 2002 Free Software Foundation, Inc. |
| dnl |
| 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 |
| dnl modify it under the terms of the GNU Lesser General Public License as |
| dnl published by the Free Software Foundation; either version 3 of the |
| dnl License, or (at your option) any later version. |
| dnl |
| dnl The GNU MP Library is distributed in the hope that it will be useful, |
| dnl but WITHOUT ANY WARRANTY; without even the implied warranty of |
| dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| dnl Lesser General Public License for more details. |
| dnl |
| dnl You should have received a copy of the GNU Lesser General Public License |
| dnl along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. |
| |
| include(`../config.m4') |
| |
| |
| C P5: 8.0 cycles/limb |
| |
| |
| C unsigned long mpn_popcount (mp_srcptr src, mp_size_t size); |
| C |
| C An arithmetic approach has been found to be slower than the table lookup, |
| C due to needing too many instructions. |
| |
| 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') |
| |
| RODATA |
| ALIGN(8) |
| GLOBL TABLE_NAME |
| TABLE_NAME: |
| forloop(i,0,255, |
| ` .byte m4_popcount(i) |
| ') |
| |
| defframe(PARAM_SIZE,8) |
| defframe(PARAM_SRC, 4) |
| |
| TEXT |
| ALIGN(8) |
| |
| PROLOGUE(mpn_popcount) |
| deflit(`FRAME',0) |
| |
| movl PARAM_SIZE, %ecx |
| pushl %esi FRAME_pushl() |
| |
| ifdef(`PIC',` |
| pushl %ebx FRAME_pushl() |
| pushl %ebp FRAME_pushl() |
| |
| call L(here) |
| L(here): |
| popl %ebp |
| shll %ecx C size in byte pairs |
| |
| addl $_GLOBAL_OFFSET_TABLE_+[.-L(here)], %ebp |
| movl PARAM_SRC, %esi |
| |
| xorl %eax, %eax C total |
| xorl %ebx, %ebx C byte |
| |
| movl TABLE_NAME@GOT(%ebp), %ebp |
| xorl %edx, %edx C byte |
| define(TABLE,`(%ebp,$1)') |
| ',` |
| dnl non-PIC |
| shll %ecx C size in byte pairs |
| movl PARAM_SRC, %esi |
| |
| pushl %ebx FRAME_pushl() |
| xorl %eax, %eax C total |
| |
| xorl %ebx, %ebx C byte |
| xorl %edx, %edx C byte |
| |
| define(TABLE,`TABLE_NAME`'($1)') |
| ') |
| |
| |
| ALIGN(8) C necessary on P55 for claimed speed |
| L(top): |
| C eax total |
| C ebx byte |
| C ecx counter, 2*size to 2 |
| C edx byte |
| C esi src |
| C edi |
| C ebp [PIC] table |
| |
| addl %ebx, %eax |
| movb -1(%esi,%ecx,2), %bl |
| |
| addl %edx, %eax |
| movb -2(%esi,%ecx,2), %dl |
| |
| 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 %esi |
| |
| ret |
| |
| EPILOGUE() |
