glibc/sysdeps/powerpc/submul_1.S

60 lines
1.8 KiB
ArmAsm

/* Multiply a limb vector by a single limb, for PowerPC.
Copyright (C) 1993-1995, 1997, 1999, 2000 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 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 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <sysdep.h>
#include <bp-sym.h>
#include <bp-asm.h>
/* mp_limb_t mpn_submul_1 (mp_ptr res_ptr, mp_srcptr s1_ptr,
mp_size_t s1_size, mp_limb_t s2_limb)
Calculate res-s1*s2 and put result back in res; return carry. */
ENTRY (BP_SYM (__mpn_submul_1))
#if __BOUNDED_POINTERS__
slwi r10,r5,2 /* convert limbs to bytes */
CHECK_BOUNDS_BOTH_WIDE (r3, r8, r9, r10)
CHECK_BOUNDS_BOTH_WIDE (r4, r8, r9, r10)
#endif
mtctr r5
lwz r0,0(r4)
mullw r7,r0,r6
mulhwu r10,r0,r6
lwz r9,0(r3)
subf r8,r7,r9
addc r7,r7,r8 # invert cy (r7 is junk)
addi r3,r3,-4 # adjust res_ptr
bdz L(1)
L(0): lwzu r0,4(r4)
stwu r8,4(r3)
mullw r8,r0,r6
adde r7,r8,r10
mulhwu r10,r0,r6
lwz r9,4(r3)
addze r10,r10
subf r8,r7,r9
addc r7,r7,r8 # invert cy (r7 is junk)
bdnz L(0)
L(1): stw r8,4(r3)
addze r3,r10
blr
END (BP_SYM (__mpn_submul_1))