| /* i80386 __mpn_rshift -- |
| Copyright (C) 1992-2016 Free Software Foundation, Inc. |
| This file is part of the GNU MP Library. |
| |
| The GNU MP Library is free software; you can redistribute it and/or modify |
| it under the terms of the GNU Lesser General Public License as published by |
| the Free Software Foundation; either version 2.1 of the License, or (at your |
| option) any later version. |
| |
| The GNU MP Library is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
| or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public |
| License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public License |
| along with the GNU MP Library; see the file COPYING.LIB. If not, |
| see <http://www.gnu.org/licenses/>. */ |
| |
| #include "sysdep.h" |
| #include "asm-syntax.h" |
| |
| #define PARMS 4+12 /* space for 3 saved regs */ |
| #define RES PARMS |
| #define S RES+4 |
| #define SIZE S+4 |
| #define CNT SIZE+4 |
| |
| .text |
| ENTRY (__mpn_rshift) |
| |
| pushl %edi |
| cfi_adjust_cfa_offset (4) |
| pushl %esi |
| cfi_adjust_cfa_offset (4) |
| pushl %ebx |
| cfi_adjust_cfa_offset (4) |
| |
| movl RES(%esp),%edi |
| cfi_rel_offset (edi, 8) |
| movl S(%esp),%esi |
| cfi_rel_offset (esi, 4) |
| movl SIZE(%esp),%edx |
| movl CNT(%esp),%ecx |
| leal -4(%edi,%edx,4),%edi |
| leal (%esi,%edx,4),%esi |
| negl %edx |
| |
| movl (%esi,%edx,4),%ebx /* read least significant limb */ |
| cfi_rel_offset (ebx, 0) |
| cfi_remember_state |
| xorl %eax,%eax |
| shrdl %cl,%ebx,%eax /* compute carry limb */ |
| incl %edx |
| jz L(end) |
| pushl %eax /* push carry limb onto stack */ |
| cfi_adjust_cfa_offset (4) |
| testb $1,%dl |
| jnz L(1) /* enter loop in the middle */ |
| movl %ebx,%eax |
| |
| ALIGN (3) |
| L(oop): movl (%esi,%edx,4),%ebx /* load next higher limb */ |
| shrdl %cl,%ebx,%eax /* compute result limb */ |
| movl %eax,(%edi,%edx,4) /* 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 /* compute most significant limb */ |
| movl %eax,(%edi) /* store it */ |
| |
| popl %eax /* pop carry limb */ |
| cfi_adjust_cfa_offset (-4) |
| |
| popl %ebx |
| cfi_adjust_cfa_offset (-4) |
| cfi_restore (ebx) |
| popl %esi |
| cfi_adjust_cfa_offset (-4) |
| cfi_restore (esi) |
| popl %edi |
| cfi_adjust_cfa_offset (-4) |
| cfi_restore (edi) |
| |
| ret |
| |
| cfi_restore_state |
| L(end): shrl %cl,%ebx /* compute most significant limb */ |
| movl %ebx,(%edi) /* store it */ |
| |
| popl %ebx |
| cfi_adjust_cfa_offset (-4) |
| cfi_restore (ebx) |
| popl %esi |
| cfi_adjust_cfa_offset (-4) |
| cfi_restore (esi) |
| popl %edi |
| cfi_adjust_cfa_offset (-4) |
| cfi_restore (edi) |
| |
| ret |
| END (__mpn_rshift) |