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-rw-r--r--sysdeps/alpha/submul_1.s23
1 files changed, 7 insertions, 16 deletions
diff --git a/sysdeps/alpha/submul_1.s b/sysdeps/alpha/submul_1.s
index acaa11c545..292b2c18b6 100644
--- a/sysdeps/alpha/submul_1.s
+++ b/sysdeps/alpha/submul_1.s
@@ -26,16 +26,7 @@
# size r18
# s2_limb r19
- # This code runs at 42 cycles/limb on the 21064.
-
- # 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?
+ # This code runs at 42 cycles/limb on EV4 and 18 cycles/limb on EV5.
.set noreorder
.set noat
@@ -52,7 +43,7 @@ __mpn_submul_1:
mulq $2,$19,$3 # $3 = prod_low
ldq $5,0($16) # $5 = *res_ptr
umulh $2,$19,$0 # $0 = prod_high
- beq $18,Lend1 # jump if size was == 1
+ beq $18,.Lend1 # jump if size was == 1
ldq $2,0($17) # $2 = s1_limb
addq $17,8,$17 # s1_ptr++
subq $18,1,$18 # size--
@@ -60,10 +51,10 @@ __mpn_submul_1:
cmpult $5,$3,$4
stq $3,0($16)
addq $16,8,$16 # res_ptr++
- beq $18,Lend2 # jump if size was == 2
+ beq $18,.Lend2 # jump if size was == 2
.align 3
-Loop: mulq $2,$19,$3 # $3 = prod_low
+.Loop: 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--
@@ -77,9 +68,9 @@ Loop: mulq $2,$19,$3 # $3 = prod_low
stq $3,0($16)
addq $16,8,$16 # res_ptr++
addq $5,$0,$0 # combine carries
- bne $18,Loop
+ bne $18,.Loop
-Lend2: mulq $2,$19,$3 # $3 = prod_low
+.Lend2: 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
@@ -91,7 +82,7 @@ Lend2: mulq $2,$19,$3 # $3 = prod_low
addq $5,$0,$0 # combine carries
addq $4,$0,$0 # cy_limb = prod_high + cy
ret $31,($26),1
-Lend1: subq $5,$3,$3
+.Lend1: subq $5,$3,$3
cmpult $5,$3,$5
stq $3,0($16)
addq $0,$5,$0