| /* PowerPC-32 rshift |
| * |
| * Copyright (C) 1995, 1998, 2002 Free Software Foundation, Inc. |
| * |
| * This file is part of Libgcrypt. |
| * |
| * Libgcrypt 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. |
| * |
| * Libgcrypt 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 this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA |
| */ |
| |
| |
| #include "sysdep.h" |
| #include "asm-syntax.h" |
| |
| |
| #ifndef USE_PPC_PATCHES |
| |
| /******************* |
| * mpi_limb_t |
| * _gcry_mpih_rshift( mpi_ptr_t wp, (r3) |
| * mpi_ptr_t up, (r4) |
| * mpi_size_t usize, (r5) |
| * unsigned cnt) (r6) |
| */ |
| |
| .toc |
| .csect .text[PR] |
| .align 2 |
| .globl _gcry_mpih_rshift |
| .globl ._gcry_mpih_rshift |
| .csect _gcry_mpih_rshift[DS] |
| _gcry_mpih_rshift: |
| .long ._gcry_mpih_rshift, TOC[tc0], 0 |
| .csect .text[PR] |
| ._gcry_mpih_rshift: |
| mtctr 5 # copy size into CTR |
| addi 7,3,-4 # move adjusted res_ptr to free return reg |
| subfic 8,6,32 |
| lwz 11,0(4) # load first s1 limb |
| slw 3,11,8 # compute function return value |
| bdz Lend1 |
| |
| Loop: lwzu 10,4(4) |
| srw 9,11,6 |
| slw 12,10,8 |
| or 9,9,12 |
| stwu 9,4(7) |
| bdz Lend2 |
| lwzu 11,4(4) |
| srw 9,10,6 |
| slw 12,11,8 |
| or 9,9,12 |
| stwu 9,4(7) |
| bdnz Loop |
| |
| Lend1: srw 0,11,6 |
| stw 0,4(7) |
| blr |
| |
| Lend2: srw 0,10,6 |
| stw 0,4(7) |
| blr |
| |
| #else |
| /* Shift a limb right, low level routine. |
| Copyright (C) 1995, 1997 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Library General Public License as |
| published by the Free Software Foundation; either version 2 of the |
| License, or (at your option) any later version. |
| |
| The GNU C 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 |
| Library General Public License for more details. |
| |
| You should have received a copy of the GNU Library General Public |
| License along with the GNU C Library; see the file COPYING.LIB. If not, |
| write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| Boston, MA 02111-1307, USA. */ |
| |
| |
| /* INPUT PARAMETERS |
| res_ptr r3 |
| s1_ptr r4 |
| size r5 |
| cnt r6 */ |
| |
| ENTRY(_gcry_mpih_rshift) |
| mtctr 5 # copy size into CTR |
| addi 7,3,-4 # move adjusted res_ptr to free return reg |
| subfic 8,6,32 |
| lwz 11,0(4) # load first s1 limb |
| slw 3,11,8 # compute function return value |
| bdz 1f |
| |
| 0: lwzu 10,4(4) |
| srw 9,11,6 |
| slw 12,10,8 |
| or 9,9,12 |
| stwu 9,4(7) |
| bdz 2f |
| lwzu 11,4(4) |
| srw 9,10,6 |
| slw 12,11,8 |
| or 9,9,12 |
| stwu 9,4(7) |
| bdnz 0b |
| |
| 1: srw 0,11,6 |
| stw 0,4(7) |
| blr |
| |
| 2: srw 0,10,6 |
| stw 0,4(7) |
| blr |
| END(_gcry_mpih_rshift) |
| #endif |
