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author | Richard Henderson <rth@twiddle.net> | 2014-02-12 06:54:57 -0800 |
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committer | Richard Henderson <rth@twiddle.net> | 2014-02-12 07:00:06 -0800 |
commit | 68b7efaadb1b6045a56277ea62d324c20ac0b633 (patch) | |
tree | 07b51c9866373430373fb90b252d46c23cc1707e /sysdeps/alpha/mul_1.S | |
parent | 8fd7b0d5591e59ed5cb3078b351bd49314a66cef (diff) | |
download | glibc-68b7efaadb1b6045a56277ea62d324c20ac0b633.zip glibc-68b7efaadb1b6045a56277ea62d324c20ac0b633.tar.gz glibc-68b7efaadb1b6045a56277ea62d324c20ac0b633.tar.bz2 |
Relocate alpha from ports to libc
Also fixed the following whitespace nits to satisfy the push:
sysdeps/alpha/alphaev6/memset.S:142: space before tab in indent.
sysdeps/alpha/configure:1: new blank line at EOF.
sysdeps/alpha/fpu/e_sqrt.c:126: space before tab in indent.
sysdeps/alpha/preconfigure:1: new blank line at EOF.
sysdeps/unix/sysv/linux/alpha/syscalls.list:1: new blank line at EOF.
Diffstat (limited to 'sysdeps/alpha/mul_1.S')
-rw-r--r-- | sysdeps/alpha/mul_1.S | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/sysdeps/alpha/mul_1.S b/sysdeps/alpha/mul_1.S new file mode 100644 index 0000000..e7474d3 --- /dev/null +++ b/sysdeps/alpha/mul_1.S @@ -0,0 +1,83 @@ + # Alpha 21064 __mpn_mul_1 -- Multiply a limb vector with a limb and store + # the result in a second limb vector. + + # Copyright (C) 1992-2014 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 2.1 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 r16 + # s1_ptr r17 + # size r18 + # s2_limb r19 + + # This code runs at 42 cycles/limb on the EV4 and 18 cycles/limb on the EV5. + + # To improve performance for long multiplications, we would use + # 'fetch' for S1 and 'fetch_m' for RES. It's not obvious how to use + # these instructions without slowing down the general code: 1. We can + # only have two prefetches in operation at any time in the Alpha + # architecture. 2. There will seldom be any special alignment + # between RES_PTR and S1_PTR. Maybe we can simply divide the current + # loop into an inner and outer loop, having the inner loop handle + # exactly one prefetch block? + + .set noreorder + .set noat +.text + .align 3 + .globl __mpn_mul_1 + .ent __mpn_mul_1 2 +__mpn_mul_1: + .frame $30,0,$26 + + ldq $2,0($17) # $2 = s1_limb + subq $18,1,$18 # size-- + mulq $2,$19,$3 # $3 = prod_low + bic $31,$31,$4 # clear cy_limb + umulh $2,$19,$0 # $0 = prod_high + beq $18,Lend1 # jump if size was == 1 + ldq $2,8($17) # $2 = s1_limb + subq $18,1,$18 # size-- + stq $3,0($16) + beq $18,Lend2 # jump if size was == 2 + + .align 3 +Loop: mulq $2,$19,$3 # $3 = prod_low + addq $4,$0,$0 # cy_limb = cy_limb + 'cy' + subq $18,1,$18 # size-- + umulh $2,$19,$4 # $4 = cy_limb + ldq $2,16($17) # $2 = s1_limb + addq $17,8,$17 # s1_ptr++ + addq $3,$0,$3 # $3 = cy_limb + prod_low + stq $3,8($16) + cmpult $3,$0,$0 # $0 = carry from (cy_limb + prod_low) + addq $16,8,$16 # res_ptr++ + bne $18,Loop + +Lend2: mulq $2,$19,$3 # $3 = prod_low + addq $4,$0,$0 # cy_limb = cy_limb + 'cy' + umulh $2,$19,$4 # $4 = cy_limb + addq $3,$0,$3 # $3 = cy_limb + prod_low + cmpult $3,$0,$0 # $0 = carry from (cy_limb + prod_low) + stq $3,8($16) + addq $4,$0,$0 # cy_limb = prod_high + cy + ret $31,($26),1 +Lend1: stq $3,0($16) + ret $31,($26),1 + + .end __mpn_mul_1 |