diff options
Diffstat (limited to 'grub-core/lib/libgcrypt/mpi/powerpc32/mpih-sub1.S')
| -rw-r--r-- | grub-core/lib/libgcrypt/mpi/powerpc32/mpih-sub1.S | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/grub-core/lib/libgcrypt/mpi/powerpc32/mpih-sub1.S b/grub-core/lib/libgcrypt/mpi/powerpc32/mpih-sub1.S new file mode 100644 index 0000000..d612ea8 --- /dev/null +++ b/grub-core/lib/libgcrypt/mpi/powerpc32/mpih-sub1.S @@ -0,0 +1,133 @@ +/* PowerPC-32 sub_n -- Subtract two limb vectors of the same length > 0 + * and store difference in a third limb vector. + * + * Copyright (C) 1992, 1994, 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_sub_n( mpi_ptr_t res_ptr, (r3) + * mpi_ptr_t s1_ptr, (r4) + * mpi_ptr_t s2_ptr, (r5) + * mpi_size_t size) (r6) + */ + + .toc + .extern _gcry_mpih_sub_n[DS] + .extern ._gcry_mpih_sub_n +.csect [PR] + .align 2 + .globl _gcry_mpih_sub_n + .globl ._gcry_mpih_sub_n + .csect _gcry_mpih_sub_n[DS] +_gcry_mpih_sub_n: + .long ._gcry_mpih_sub_n, TOC[tc0], 0 + .csect [PR] +._gcry_mpih_sub_n: + mtctr 6 # copy size into CTR + lwz 8,0(4) # load least significant s1 limb + lwz 0,0(5) # load least significant s2 limb + addi 3,3,-4 # offset res_ptr, it is updated before used + subfc 7,0,8 # add least significant limbs, set cy + bdz Lend # If done, skip loop +Loop: lwzu 8,4(4) # load s1 limb and update s1_ptr + lwzu 0,4(5) # load s2 limb and update s2_ptr + stwu 7,4(3) # store previous limb in load latency slot + subfe 7,0,8 # add new limbs with cy, set cy + bdnz Loop # decrement CTR and loop back +Lend: stw 7,4(3) # store ultimate result limb + subfe 3,0,0 # load !cy into ... + subfic 3,3,0 # ... return value register + blr + +#else +/* Subtract two limb vectors of equal, non-zero length for PowerPC. + Copyright (C) 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. */ + +/* mp_limb_t mpn_sub_n (mp_ptr res_ptr, mp_srcptr s1_ptr, mp_srcptr s2_ptr, + mp_size_t size) + Calculate s1-s2 and put result in res_ptr; return borrow, 0 or 1. */ + +/* Note on optimisation: This code is optimal for the 601. Almost every other + possible 2-unrolled inner loop will not be. Also, watch out for the + alignment... */ + +EALIGN(_gcry_mpih_sub_n,3,1) +/* Set up for loop below. */ + mtcrf 0x01,%r6 + srwi. %r7,%r6,1 + mtctr %r7 + bt 31,2f + +/* Set the carry (clear the borrow). */ + subfc %r0,%r0,%r0 +/* Adjust pointers for loop. */ + addi %r3,%r3,-4 + addi %r4,%r4,-4 + addi %r5,%r5,-4 + b 0f + +2: lwz %r7,0(%r5) + lwz %r6,0(%r4) + subfc %r6,%r7,%r6 + stw %r6,0(%r3) + beq 1f + +/* Align start of loop to an odd word boundary to guarantee that the + last two words can be fetched in one access (for 601). This turns + out to be important. */ +0: + lwz %r9,4(%r4) + lwz %r8,4(%r5) + lwzu %r6,8(%r4) + lwzu %r7,8(%r5) + subfe %r8,%r8,%r9 + stw %r8,4(%r3) + subfe %r6,%r7,%r6 + stwu %r6,8(%r3) + bdnz 0b +/* Return the borrow. */ +1: subfe %r3,%r3,%r3 + neg %r3,%r3 + blr +END(_gcry_mpih_sub_n) +#endif |