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()