diff options
Diffstat (limited to 'sysdeps/hppa/hppa1.1/submul_1.s')
| -rw-r--r-- | sysdeps/hppa/hppa1.1/submul_1.s | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/sysdeps/hppa/hppa1.1/submul_1.s b/sysdeps/hppa/hppa1.1/submul_1.s new file mode 100644 index 0000000000..44cabf4690 --- /dev/null +++ b/sysdeps/hppa/hppa1.1/submul_1.s @@ -0,0 +1,110 @@ +; HP-PA-1.1 __mpn_submul_1 -- Multiply a limb vector with a limb and +; subtract the result from a second limb vector. + +; Copyright (C) 1992, 1993, 1994 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 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 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 Library General Public +; License for more details. + +; You should have received a copy of the GNU Library General Public License +; along with the GNU MP Library; see the file COPYING.LIB. If not, write to +; the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + + +; INPUT PARAMETERS +; res_ptr r26 +; s1_ptr r25 +; size r24 +; s2_limb r23 + +; This runs at 12 cycles/limb on a PA7000. With the used instructions, it +; can not become faster due to data cache contention after a store. On the +; PA7100 it runs at 11 cycles/limb, and that can not be improved either, +; since only the xmpyu does not need the integer pipeline, so the only +; dual-issue we will get are addc+xmpyu. Unrolling could gain a cycle/limb +; on the PA7100. + +; There are some ideas described in mul_1.s that applies to this code too. + +; It seems possible to make this run as fast as __mpn_addmul_1, if we use +; sub,>>= %r29,%r19,%r22 +; addi 1,%r28,%r28 +; but that requires reworking the hairy software pipeline... + + .code + .export __mpn_submul_1 +__mpn_submul_1 + .proc + .callinfo frame=64,no_calls + .entry + + ldo 64(%r30),%r30 + fldws,ma 4(%r25),%fr5 + stw %r23,-16(%r30) ; move s2_limb ... + addib,= -1,%r24,L$just_one_limb + fldws -16(%r30),%fr4 ; ... into fr4 + add %r0,%r0,%r0 ; clear carry + xmpyu %fr4,%fr5,%fr6 + fldws,ma 4(%r25),%fr7 + fstds %fr6,-16(%r30) + xmpyu %fr4,%fr7,%fr8 + ldw -12(%r30),%r19 ; least significant limb in product + ldw -16(%r30),%r28 + + fstds %fr8,-16(%r30) + addib,= -1,%r24,L$end + ldw -12(%r30),%r1 + +; Main loop +L$loop ldws 0(%r26),%r29 + fldws,ma 4(%r25),%fr5 + sub %r29,%r19,%r22 + add %r22,%r19,%r0 + stws,ma %r22,4(%r26) + addc %r28,%r1,%r19 + xmpyu %fr4,%fr5,%fr6 + ldw -16(%r30),%r28 + fstds %fr6,-16(%r30) + addc %r0,%r28,%r28 + addib,<> -1,%r24,L$loop + ldw -12(%r30),%r1 + +L$end ldw 0(%r26),%r29 + sub %r29,%r19,%r22 + add %r22,%r19,%r0 + stws,ma %r22,4(%r26) + addc %r28,%r1,%r19 + ldw -16(%r30),%r28 + ldws 0(%r26),%r29 + addc %r0,%r28,%r28 + sub %r29,%r19,%r22 + add %r22,%r19,%r0 + stws,ma %r22,4(%r26) + addc %r0,%r28,%r28 + bv 0(%r2) + ldo -64(%r30),%r30 + +L$just_one_limb + xmpyu %fr4,%fr5,%fr6 + ldw 0(%r26),%r29 + fstds %fr6,-16(%r30) + ldw -12(%r30),%r1 + ldw -16(%r30),%r28 + sub %r29,%r1,%r22 + add %r22,%r1,%r0 + stw %r22,0(%r26) + addc %r0,%r28,%r28 + bv 0(%r2) + ldo -64(%r30),%r30 + + .exit + .procend |