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+; HP-PA-1.1 __mpn_mul_1 -- Multiply a limb vector with a limb and store
+; the result in 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 9 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 7 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 would not help either CPU.
+
+; We could use fldds to read two limbs at a time from the S1 array, and that
+; could bring down the times to 8.5 and 6.5 cycles/limb for the PA7000 and
+; PA7100, respectively. We don't do that since it does not seem worth the
+; (alignment) troubles...
+
+; At least the PA7100 is rumored to be able to deal with cache-misses
+; without stalling instruction issue. If this is true, and the cache is
+; actually also lockup-free, we should use a deeper software pipeline, and
+; load from S1 very early! (The loads and stores to -12(sp) will surely be
+; in the cache.)
+
+ .code
+ .export __mpn_mul_1
+__mpn_mul_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$loop fldws,ma 4(%r25),%fr5
+ stws,ma %r19,4(%r26)
+ addc %r28,%r1,%r19
+ xmpyu %fr4,%fr5,%fr6
+ ldw -16(%r30),%r28
+ fstds %fr6,-16(%r30)
+ addib,<> -1,%r24,L$loop
+ ldw -12(%r30),%r1
+
+L$end stws,ma %r19,4(%r26)
+ addc %r28,%r1,%r19
+ ldw -16(%r30),%r28
+ stws,ma %r19,4(%r26)
+ addc %r0,%r28,%r28
+ bv 0(%r2)
+ ldo -64(%r30),%r30
+
+L$just_one_limb
+ xmpyu %fr4,%fr5,%fr6
+ fstds %fr6,-16(%r30)
+ ldw -16(%r30),%r28
+ ldo -64(%r30),%r30
+ bv 0(%r2)
+ fstws %fr6R,0(%r26)
+
+ .exit
+ .procend