glibc/sysdeps/powerpc/powerpc32/submul_1.S

52 lines
1.5 KiB
ArmAsm

/* Multiply a limb vector by a single limb, for PowerPC.
Copyright (C) 1993-2017 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, see
<http://www.gnu.org/licenses/>. */
#include <sysdep.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 (__mpn_submul_1)
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 (__mpn_submul_1)