Imported gcc-4.4.3

[msp430-gcc.git] / gmp / mpn / a29k / sub_n.s

diff --git a/gmp/mpn/a29k/sub_n.s b/gmp/mpn/a29k/sub_n.s
new file mode 100644 (file)
index 0000000..42072a4
--- /dev/null
+++ b/gmp/mpn/a29k/sub_n.s
@@ -0,0 +1,118 @@
+; 29000 mpn_sub_n -- Subtract two limb vectors of the same length > 0 and
+; store difference in a third limb vector.
+
+; Copyright 1992, 1994, 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      lr2
+; s1_ptr       lr3
+; s2_ptr       lr4
+; size         lr5
+
+; We use the loadm/storem instructions and operate on chunks of 8
+; limbs/per iteration, until less than 8 limbs remain.
+
+; The 29k has no addition or subtraction instructions that doesn't
+; affect carry, so we need to save and restore that as soon as we
+; adjust the pointers.  gr116 is used for this purpose.  Note that
+; gr116==0 means that carry should be set.
+
+       .sect .lit,lit
+       .text
+       .align  4
+       .global ___gmpn_sub_n
+       .word   0x60000
+___gmpn_sub_n:
+       srl     gr117,lr5,3
+       sub     gr118,gr117,1
+       jmpt    gr118,Ltail
+        constn gr116,-1                ; init cy reg
+       sub     gr117,gr117,2           ; count for jmpfdec
+
+; Main loop working 8 limbs/iteration.
+Loop:  mtsrim  cr,(8-1)
+       loadm   0,0,gr96,lr3
+       add     lr3,lr3,32
+       mtsrim  cr,(8-1)
+       loadm   0,0,gr104,lr4
+       add     lr4,lr4,32
+
+       subr    gr116,gr116,0           ; restore carry
+       subc    gr96,gr96,gr104
+       subc    gr97,gr97,gr105
+       subc    gr98,gr98,gr106
+       subc    gr99,gr99,gr107
+       subc    gr100,gr100,gr108
+       subc    gr101,gr101,gr109
+       subc    gr102,gr102,gr110
+       subc    gr103,gr103,gr111
+       subc    gr116,gr116,gr116       ; gr116 = not(cy)
+
+       mtsrim  cr,(8-1)
+       storem  0,0,gr96,lr2
+       jmpfdec gr117,Loop
+        add    lr2,lr2,32
+
+; Code for the last up-to-7 limbs.
+; This code might look very strange, but it's hard to write it
+; differently without major slowdown.
+
+       and     lr5,lr5,(8-1)
+Ltail: sub     gr118,lr5,1             ; count for CR
+       jmpt    gr118,Lend
+        sub    gr117,lr5,2             ; count for jmpfdec
+
+       mtsr    cr,gr118
+       loadm   0,0,gr96,lr3
+       mtsr    cr,gr118
+       loadm   0,0,gr104,lr4
+
+       subr    gr116,gr116,0           ; restore carry
+
+       jmpfdec gr117,L1
+        subc   gr96,gr96,gr104
+       jmp     Lstore
+        mtsr   cr,gr118
+L1:    jmpfdec gr117,L2
+        subc   gr97,gr97,gr105
+       jmp     Lstore
+        mtsr   cr,gr118
+L2:    jmpfdec gr117,L3
+        subc   gr98,gr98,gr106
+       jmp     Lstore
+        mtsr   cr,gr118
+L3:    jmpfdec gr117,L4
+        subc   gr99,gr99,gr107
+       jmp     Lstore
+        mtsr   cr,gr118
+L4:    jmpfdec gr117,L5
+        subc   gr100,gr100,gr108
+       jmp     Lstore
+        mtsr   cr,gr118
+L5:    jmpfdec gr117,L6
+        subc   gr101,gr101,gr109
+       jmp     Lstore
+        mtsr   cr,gr118
+L6:    subc    gr102,gr102,gr110
+
+Lstore:        storem  0,0,gr96,lr2
+       subc    gr116,gr116,gr116       ; gr116 = not(cy)
+
+Lend:  jmpi    lr0
+        add    gr96,gr116,1