diff options
Diffstat (limited to 'rts/gmp/mpn/x86/rshift.asm')
| -rw-r--r-- | rts/gmp/mpn/x86/rshift.asm | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/rts/gmp/mpn/x86/rshift.asm b/rts/gmp/mpn/x86/rshift.asm new file mode 100644 index 0000000000..c9881fd966 --- /dev/null +++ b/rts/gmp/mpn/x86/rshift.asm @@ -0,0 +1,92 @@ +dnl x86 mpn_rshift -- mpn right shift. + +dnl Copyright (C) 1992, 1994, 1996, 1999, 2000 Free Software Foundation, +dnl 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 2.1 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 +dnl License along with the GNU MP Library; see the file COPYING.LIB. If +dnl not, write to the Free Software Foundation, Inc., 59 Temple Place - +dnl Suite 330, Boston, MA 02111-1307, USA. + + +include(`../config.m4') + + +C mp_limb_t mpn_rshift (mp_ptr dst, mp_srcptr src, mp_size_t size, +C unsigned shift); + +defframe(PARAM_SHIFT,16) +defframe(PARAM_SIZE, 12) +defframe(PARAM_SRC, 8) +defframe(PARAM_DST, 4) + + .text + ALIGN(8) +PROLOGUE(mpn_rshift) + + pushl %edi + pushl %esi + pushl %ebx +deflit(`FRAME',12) + + movl PARAM_DST,%edi + movl PARAM_SRC,%esi + movl PARAM_SIZE,%edx + movl PARAM_SHIFT,%ecx + + leal -4(%edi,%edx,4),%edi + leal (%esi,%edx,4),%esi + negl %edx + + movl (%esi,%edx,4),%ebx C read least significant limb + xorl %eax,%eax + shrdl( %cl, %ebx, %eax) C compute carry limb + incl %edx + jz L(end) + pushl %eax C push carry limb onto stack + testb $1,%dl + jnz L(1) C enter loop in the middle + movl %ebx,%eax + + ALIGN(8) +L(oop): movl (%esi,%edx,4),%ebx C load next higher limb + shrdl( %cl, %ebx, %eax) C compute result limb + movl %eax,(%edi,%edx,4) C store it + incl %edx +L(1): movl (%esi,%edx,4),%eax + shrdl( %cl, %eax, %ebx) + movl %ebx,(%edi,%edx,4) + incl %edx + jnz L(oop) + + shrl %cl,%eax C compute most significant limb + movl %eax,(%edi) C store it + + popl %eax C pop carry limb + + popl %ebx + popl %esi + popl %edi + ret + +L(end): shrl %cl,%ebx C compute most significant limb + movl %ebx,(%edi) C store it + + popl %ebx + popl %esi + popl %edi + ret + +EPILOGUE() |