Imported gcc-4.4.3

[msp430-gcc.git] / gmp / mpn / thumb / add_n.s

diff --git a/gmp/mpn/thumb/add_n.s b/gmp/mpn/thumb/add_n.s
new file mode 100644 (file)
index 0000000..294cfe6
--- /dev/null
+++ b/gmp/mpn/thumb/add_n.s
@@ -0,0 +1,48 @@
+@ ARM/Thumb mpn_add_n -- Add two limb vectors of the same length > 0 and store
+@ sum in a third limb vector.
+
+@ Copyright 1997, 2000 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 3 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.  If not, see http://www.gnu.org/licenses/.
+
+
+@ INPUT PARAMETERS
+@ RES_ptr      r0
+@ S1_ptr       r1
+@ S2_ptr       r2
+@ SIZE         r3
+
+@ NOT TESTED CODE
+
+       .text
+       .thumb
+       .align  0
+       .global ___gmpn_add_n
+___gmpn_add_n:
+       push    {r4, r5, r6, lr}
+       mov     r6, #1                  @ init carry save register
+
+Loop:  sub     r6, #1                  @ restore carry (set iff r6 was 0)
+       ldmia   r1!, {r4}               @ load next limb from S1
+       ldmia   r2!, {r5}               @ load next limb from S2
+       adc     r4, r5
+       stmia   r0!, {r4}               @ store result limb to RES
+       sbc     r6, r6                  @ save negated carry
+       sub     r3, #1
+       bge     Loop                    @ loop back while remaining count >= 4
+
+       mov     r0, r6
+       pop     {r4, r5, r6, pc}