diff options
Diffstat (limited to 'ports/sysdeps/alpha/alphaev6/addmul_1.S')
| -rw-r--r-- | ports/sysdeps/alpha/alphaev6/addmul_1.S | 477 |
1 files changed, 477 insertions, 0 deletions
diff --git a/ports/sysdeps/alpha/alphaev6/addmul_1.S b/ports/sysdeps/alpha/alphaev6/addmul_1.S new file mode 100644 index 0000000000..c663f0a1d2 --- /dev/null +++ b/ports/sysdeps/alpha/alphaev6/addmul_1.S @@ -0,0 +1,477 @@ + # Alpha ev6 mpn_addmul_1 -- Multiply a limb vector with a limb and add + # the result to a second limb vector. + # + # Copyright (C) 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 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 $16 + # s1_ptr $17 + # size $18 + # s2_limb $19 + # + # This code runs at 42 cycles/limb on EV4, 18 cycles/limb on EV5, and + # exactly 3.625 cycles/limb on EV6... + # + # This code was written in close cooperation with ev6 pipeline expert + # Steve Root (root@toober.hlo.dec.com). Any errors are tege's fault, though. + # + # Register usages for unrolled loop: + # 0-3 mul's + # 4-7 acc's + # 8-15 mul results + # 20,21 carry's + # 22,23 save for stores + # + # Sustains 8 mul-adds in 29 cycles in the unrolled inner loop. + # + # The stores can issue a cycle late so we have paired no-op's to 'catch' + # them, so that further disturbance to the schedule is damped. + # + # We couldn't pair the loads, because the entangled schedule of the + # carry's has to happen on one side {0} of the machine. Note, the total + # use of U0, and the total use of L0 (after attending to the stores). + # which is part of the reason why.... + # + # This is a great schedule for the d_cache, a poor schedule for the + # b_cache. The lockup on U0 means that any stall can't be recovered + # from. Consider a ldq in L1. say that load gets stalled because it + # collides with a fill from the b_Cache. On the next cycle, this load + # gets priority. If first looks at L0, and goes there. The instruction + # we intended for L0 gets to look at L1, which is NOT where we want + # it. It either stalls 1, because it can't go in L0, or goes there, and + # causes a further instruction to stall. + # + # So for b_cache, we're likely going to want to put one or more cycles + # back into the code! And, of course, put in prefetches. For the + # accumulator, lds, intent to modify. For the multiplier, you might + # want ldq, evict next, if you're not wanting to use it again soon. Use + # 256 ahead of present pointer value. At a place where we have an mt + # followed by a bookkeeping, put the bookkeeping in upper, and the + # prefetch into lower. + # + # Note, the usage of physical registers per cycle is smoothed off, as + # much as possible. + # + # Note, the ldq's and stq's are at the end of the quadpacks. note, we'd + # like not to have a ldq or stq to preceded a conditional branch in a + # quadpack. The conditional branch moves the retire pointer one cycle + # later. + # + # Optimization notes: + # Callee-saves regs: $9 $10 $11 $12 $13 $14 $15 $26 ?$27? + # Reserved regs: $29 $30 $31 + # Free caller-saves regs in unrolled code: $24 $25 $28 + # We should swap some of the callee-saves regs for some of the free + # caller-saves regs, saving some overhead cycles. + # Most importantly, we should write fast code for the 0-7 case. + # The code we use there are for the 21164, and runs at 7 cycles/limb + # on the 21264. Should not be hard, if we write specialized code for + # 1-7 limbs (the one for 0 limbs should be straightforward). We then just + # need a jump table indexed by the low 3 bits of the count argument. + + .set noreorder + .set noat + .text + + .globl __mpn_addmul_1 + .ent __mpn_addmul_1 +__mpn_addmul_1: + .frame $30,0,$26,0 + .prologue 0 + + cmpult $18, 8, $1 + beq $1, $Large + + ldq $2, 0($17) # $2 = s1_limb + addq $17, 8, $17 # s1_ptr++ + subq $18, 1, $18 # size-- + mulq $2, $19, $3 # $3 = prod_low + ldq $5, 0($16) # $5 = *res_ptr + umulh $2, $19, $0 # $0 = prod_high + beq $18, $Lend0b # jump if size was == 1 + ldq $2, 0($17) # $2 = s1_limb + addq $17, 8, $17 # s1_ptr++ + subq $18, 1, $18 # size-- + addq $5, $3, $3 + cmpult $3, $5, $4 + stq $3, 0($16) + addq $16, 8, $16 # res_ptr++ + beq $18, $Lend0a # jump if size was == 2 + + .align 3 +$Loop0: mulq $2, $19, $3 # $3 = prod_low + ldq $5, 0($16) # $5 = *res_ptr + addq $4, $0, $0 # cy_limb = cy_limb + 'cy' + subq $18, 1, $18 # size-- + umulh $2, $19, $4 # $4 = cy_limb + ldq $2, 0($17) # $2 = s1_limb + addq $17, 8, $17 # s1_ptr++ + addq $3, $0, $3 # $3 = cy_limb + prod_low + cmpult $3, $0, $0 # $0 = carry from (cy_limb + prod_low) + addq $5, $3, $3 + cmpult $3, $5, $5 + stq $3, 0($16) + addq $16, 8, $16 # res_ptr++ + addq $5, $0, $0 # combine carries + bne $18, $Loop0 +$Lend0a: + mulq $2, $19, $3 # $3 = prod_low + ldq $5, 0($16) # $5 = *res_ptr + 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) + addq $5, $3, $3 + cmpult $3, $5, $5 + stq $3, 0($16) + addq $5, $0, $0 # combine carries + addq $4, $0, $0 # cy_limb = prod_high + cy + ret $31, ($26), 1 +$Lend0b: + addq $5, $3, $3 + cmpult $3, $5, $5 + stq $3, 0($16) + addq $0, $5, $0 + ret $31, ($26), 1 + +$Large: + lda $30, -240($30) + stq $9, 8($30) + stq $10, 16($30) + stq $11, 24($30) + stq $12, 32($30) + stq $13, 40($30) + stq $14, 48($30) + stq $15, 56($30) + + and $18, 7, $20 # count for the first loop, 0-7 + srl $18, 3, $18 # count for unrolled loop + bis $31, $31, $0 + beq $20, $Lunroll + ldq $2, 0($17) # $2 = s1_limb + addq $17, 8, $17 # s1_ptr++ + subq $20, 1, $20 # size-- + mulq $2, $19, $3 # $3 = prod_low + ldq $5, 0($16) # $5 = *res_ptr + umulh $2, $19, $0 # $0 = prod_high + beq $20, $Lend1b # jump if size was == 1 + ldq $2, 0($17) # $2 = s1_limb + addq $17, 8, $17 # s1_ptr++ + subq $20, 1, $20 # size-- + addq $5, $3, $3 + cmpult $3, $5, $4 + stq $3, 0($16) + addq $16, 8, $16 # res_ptr++ + beq $20, $Lend1a # jump if size was == 2 + + .align 3 +$Loop1: mulq $2, $19, $3 # $3 = prod_low + ldq $5, 0($16) # $5 = *res_ptr + addq $4, $0, $0 # cy_limb = cy_limb + 'cy' + subq $20, 1, $20 # size-- + umulh $2, $19, $4 # $4 = cy_limb + ldq $2, 0($17) # $2 = s1_limb + addq $17, 8, $17 # s1_ptr++ + addq $3, $0, $3 # $3 = cy_limb + prod_low + cmpult $3, $0, $0 # $0 = carry from (cy_limb + prod_low) + addq $5, $3, $3 + cmpult $3, $5, $5 + stq $3, 0($16) + addq $16, 8, $16 # res_ptr++ + addq $5, $0, $0 # combine carries + bne $20, $Loop1 + +$Lend1a: + mulq $2, $19, $3 # $3 = prod_low + ldq $5, 0($16) # $5 = *res_ptr + 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) + addq $5, $3, $3 + cmpult $3, $5, $5 + stq $3, 0($16) + addq $16, 8, $16 # res_ptr++ + addq $5, $0, $0 # combine carries + addq $4, $0, $0 # cy_limb = prod_high + cy + br $31, $Lunroll +$Lend1b: + addq $5, $3, $3 + cmpult $3, $5, $5 + stq $3, 0($16) + addq $16, 8, $16 # res_ptr++ + addq $0, $5, $0 + +$Lunroll: + lda $17, -16($17) # L1 bookkeeping + lda $16, -16($16) # L1 bookkeeping + bis $0, $31, $12 + + # ____ UNROLLED LOOP SOFTWARE PIPELINE STARTUP ____ + + ldq $2, 16($17) # L1 + ldq $3, 24($17) # L1 + lda $18, -1($18) # L1 bookkeeping + ldq $6, 16($16) # L1 + ldq $7, 24($16) # L1 + ldq $0, 32($17) # L1 + mulq $19, $2, $13 # U1 + ldq $1, 40($17) # L1 + umulh $19, $2, $14 # U1 + mulq $19, $3, $15 # U1 + lda $17, 64($17) # L1 bookkeeping + ldq $4, 32($16) # L1 + ldq $5, 40($16) # L1 + umulh $19, $3, $8 # U1 + ldq $2, -16($17) # L1 + mulq $19, $0, $9 # U1 + ldq $3, -8($17) # L1 + umulh $19, $0, $10 # U1 + addq $6, $13, $6 # L0 lo + acc + mulq $19, $1, $11 # U1 + cmpult $6, $13, $20 # L0 lo add => carry + lda $16, 64($16) # L1 bookkeeping + addq $6, $12, $22 # U0 hi add => answer + cmpult $22, $12, $21 # L0 hi add => carry + addq $14, $20, $14 # U0 hi mul + carry + ldq $6, -16($16) # L1 + addq $7, $15, $23 # L0 lo + acc + addq $14, $21, $14 # U0 hi mul + carry + ldq $7, -8($16) # L1 + umulh $19, $1, $12 # U1 + cmpult $23, $15, $20 # L0 lo add => carry + addq $23, $14, $23 # U0 hi add => answer + ldq $0, 0($17) # L1 + mulq $19, $2, $13 # U1 + cmpult $23, $14, $21 # L0 hi add => carry + addq $8, $20, $8 # U0 hi mul + carry + ldq $1, 8($17) # L1 + umulh $19, $2, $14 # U1 + addq $4, $9, $4 # L0 lo + acc + stq $22, -48($16) # L0 + stq $23, -40($16) # L1 + mulq $19, $3, $15 # U1 + addq $8, $21, $8 # U0 hi mul + carry + cmpult $4, $9, $20 # L0 lo add => carry + addq $4, $8, $22 # U0 hi add => answer + ble $18, $Lend # U1 bookkeeping + + # ____ MAIN UNROLLED LOOP ____ + .align 4 +$Loop: + bis $31, $31, $31 # U1 mt + cmpult $22, $8, $21 # L0 hi add => carry + addq $10, $20, $10 # U0 hi mul + carry + ldq $4, 0($16) # L1 + + bis $31, $31, $31 # U1 mt + addq $5, $11, $23 # L0 lo + acc + addq $10, $21, $10 # L0 hi mul + carry + ldq $5, 8($16) # L1 + + umulh $19, $3, $8 # U1 + cmpult $23, $11, $20 # L0 lo add => carry + addq $23, $10, $23 # U0 hi add => answer + ldq $2, 16($17) # L1 + + mulq $19, $0, $9 # U1 + cmpult $23, $10, $21 # L0 hi add => carry + addq $12, $20, $12 # U0 hi mul + carry + ldq $3, 24($17) # L1 + + umulh $19, $0, $10 # U1 + addq $6, $13, $6 # L0 lo + acc + stq $22, -32($16) # L0 + stq $23, -24($16) # L1 + + bis $31, $31, $31 # L0 st slosh + mulq $19, $1, $11 # U1 + bis $31, $31, $31 # L1 st slosh + addq $12, $21, $12 # U0 hi mul + carry + + cmpult $6, $13, $20 # L0 lo add => carry + bis $31, $31, $31 # U1 mt + lda $18, -1($18) # L1 bookkeeping + addq $6, $12, $22 # U0 hi add => answer + + bis $31, $31, $31 # U1 mt + cmpult $22, $12, $21 # L0 hi add => carry + addq $14, $20, $14 # U0 hi mul + carry + ldq $6, 16($16) # L1 + + bis $31, $31, $31 # U1 mt + addq $7, $15, $23 # L0 lo + acc + addq $14, $21, $14 # U0 hi mul + carry + ldq $7, 24($16) # L1 + + umulh $19, $1, $12 # U1 + cmpult $23, $15, $20 # L0 lo add => carry + addq $23, $14, $23 # U0 hi add => answer + ldq $0, 32($17) # L1 + + mulq $19, $2, $13 # U1 + cmpult $23, $14, $21 # L0 hi add => carry + addq $8, $20, $8 # U0 hi mul + carry + ldq $1, 40($17) # L1 + + umulh $19, $2, $14 # U1 + addq $4, $9, $4 # U0 lo + acc + stq $22, -16($16) # L0 + stq $23, -8($16) # L1 + + bis $31, $31, $31 # L0 st slosh + mulq $19, $3, $15 # U1 + bis $31, $31, $31 # L1 st slosh + addq $8, $21, $8 # L0 hi mul + carry + + cmpult $4, $9, $20 # L0 lo add => carry + bis $31, $31, $31 # U1 mt + lda $17, 64($17) # L1 bookkeeping + addq $4, $8, $22 # U0 hi add => answer + + bis $31, $31, $31 # U1 mt + cmpult $22, $8, $21 # L0 hi add => carry + addq $10, $20, $10 # U0 hi mul + carry + ldq $4, 32($16) # L1 + + bis $31, $31, $31 # U1 mt + addq $5, $11, $23 # L0 lo + acc + addq $10, $21, $10 # L0 hi mul + carry + ldq $5, 40($16) # L1 + + umulh $19, $3, $8 # U1 + cmpult $23, $11, $20 # L0 lo add => carry + addq $23, $10, $23 # U0 hi add => answer + ldq $2, -16($17) # L1 + + mulq $19, $0, $9 # U1 + cmpult $23, $10, $21 # L0 hi add => carry + addq $12, $20, $12 # U0 hi mul + carry + ldq $3, -8($17) # L1 + + umulh $19, $0, $10 # U1 + addq $6, $13, $6 # L0 lo + acc + stq $22, 0($16) # L0 + stq $23, 8($16) # L1 + + bis $31, $31, $31 # L0 st slosh + mulq $19, $1, $11 # U1 + bis $31, $31, $31 # L1 st slosh + addq $12, $21, $12 # U0 hi mul + carry + + cmpult $6, $13, $20 # L0 lo add => carry + bis $31, $31, $31 # U1 mt + lda $16, 64($16) # L1 bookkeeping + addq $6, $12, $22 # U0 hi add => answer + + bis $31, $31, $31 # U1 mt + cmpult $22, $12, $21 # L0 hi add => carry + addq $14, $20, $14 # U0 hi mul + carry + ldq $6, -16($16) # L1 + + bis $31, $31, $31 # U1 mt + addq $7, $15, $23 # L0 lo + acc + addq $14, $21, $14 # U0 hi mul + carry + ldq $7, -8($16) # L1 + + umulh $19, $1, $12 # U1 + cmpult $23, $15, $20 # L0 lo add => carry + addq $23, $14, $23 # U0 hi add => answer + ldq $0, 0($17) # L1 + + mulq $19, $2, $13 # U1 + cmpult $23, $14, $21 # L0 hi add => carry + addq $8, $20, $8 # U0 hi mul + carry + ldq $1, 8($17) # L1 + + umulh $19, $2, $14 # U1 + addq $4, $9, $4 # L0 lo + acc + stq $22, -48($16) # L0 + stq $23, -40($16) # L1 + + bis $31, $31, $31 # L0 st slosh + mulq $19, $3, $15 # U1 + bis $31, $31, $31 # L1 st slosh + addq $8, $21, $8 # U0 hi mul + carry + + cmpult $4, $9, $20 # L0 lo add => carry + addq $4, $8, $22 # U0 hi add => answer + bis $31, $31, $31 # L1 mt + bgt $18, $Loop # U1 bookkeeping + +# ____ UNROLLED LOOP SOFTWARE PIPELINE FINISH ____ +$Lend: + cmpult $22, $8, $21 # L0 hi add => carry + addq $10, $20, $10 # U0 hi mul + carry + ldq $4, 0($16) # L1 + addq $5, $11, $23 # L0 lo + acc + addq $10, $21, $10 # L0 hi mul + carry + ldq $5, 8($16) # L1 + umulh $19, $3, $8 # U1 + cmpult $23, $11, $20 # L0 lo add => carry + addq $23, $10, $23 # U0 hi add => answer + mulq $19, $0, $9 # U1 + cmpult $23, $10, $21 # L0 hi add => carry + addq $12, $20, $12 # U0 hi mul + carry + umulh $19, $0, $10 # U1 + addq $6, $13, $6 # L0 lo + acc + stq $22, -32($16) # L0 + stq $23, -24($16) # L1 + mulq $19, $1, $11 # U1 + addq $12, $21, $12 # U0 hi mul + carry + cmpult $6, $13, $20 # L0 lo add => carry + addq $6, $12, $22 # U0 hi add => answer + cmpult $22, $12, $21 # L0 hi add => carry + addq $14, $20, $14 # U0 hi mul + carry + addq $7, $15, $23 # L0 lo + acc + addq $14, $21, $14 # U0 hi mul + carry + umulh $19, $1, $12 # U1 + cmpult $23, $15, $20 # L0 lo add => carry + addq $23, $14, $23 # U0 hi add => answer + cmpult $23, $14, $21 # L0 hi add => carry + addq $8, $20, $8 # U0 hi mul + carry + addq $4, $9, $4 # U0 lo + acc + stq $22, -16($16) # L0 + stq $23, -8($16) # L1 + bis $31, $31, $31 # L0 st slosh + addq $8, $21, $8 # L0 hi mul + carry + cmpult $4, $9, $20 # L0 lo add => carry + addq $4, $8, $22 # U0 hi add => answer + cmpult $22, $8, $21 # L0 hi add => carry + addq $10, $20, $10 # U0 hi mul + carry + addq $5, $11, $23 # L0 lo + acc + addq $10, $21, $10 # L0 hi mul + carry + cmpult $23, $11, $20 # L0 lo add => carry + addq $23, $10, $23 # U0 hi add => answer + cmpult $23, $10, $21 # L0 hi add => carry + addq $12, $20, $12 # U0 hi mul + carry + stq $22, 0($16) # L0 + stq $23, 8($16) # L1 + addq $12, $21, $0 # U0 hi mul + carry + + ldq $9, 8($30) + ldq $10, 16($30) + ldq $11, 24($30) + ldq $12, 32($30) + ldq $13, 40($30) + ldq $14, 48($30) + ldq $15, 56($30) + lda $30, 240($30) + ret $31, ($26), 1 + + .end __mpn_addmul_1 |