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few 6502 and some 65SC02 optimizations

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IrgendwerA8
2017-03-12 23:21:43 +01:00
parent 0ec4534bd6
commit 0de44517ac
23 changed files with 272 additions and 78 deletions
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59
libsrc/runtime/add.s
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@@ -1,5 +1,6 @@
;
; Ullrich von Bassewitz, 05.08.1998
; Christian Krueger, 11-Mar-2017, spend two bytes for one cycle, improved 65SC02 optimization
;
; CC65 runtime: add ints
;
@@ -8,32 +9,46 @@
; called a lot!
.export tosadda0, tosaddax
.importzp sp
.importzp sp, tmp1
.macpack cpu
tosadda0:
ldx #0
tosaddax:
clc
.if (.cpu .bitand CPU_ISET_65SC02)
adc (sp) ; 65SC02 version - saves 2 cycles
ldy #1
.else
ldy #0
adc (sp),y ; lo byte
iny
.endif
pha ; save it
txa
adc (sp),y ; hi byte
tax
clc
lda sp
adc #2
sta sp
bcc L1
inc sp+1
L1: pla ; Restore low byte
rts
clc ; (2)
.if (.cpu .bitand ::CPU_ISET_65SC02)
adc (sp) ; (7)
tay ; (9)
inc sp ; (14)
bne hiadd ; (17)
inc sp+1 ; (-1+5)
hiadd: txa ; (19)
adc (sp) ; (24)
tax ; (26)
inc sp ; (31)
bne done ; (34)
inc sp+1 ; (-1+5)
done: tya ; (36)
.else
ldy #0 ; (4)
adc (sp),y ; (9) lo byte
iny ; (11)
sta tmp1 ; (14) save it
txa ; (16)
adc (sp),y ; (21) hi byte
tax ; (23)
clc ; (25)
lda sp ; (28)
adc #2 ; (30)
sta sp ; (33)
bcc L1 ; (36)
inc sp+1 ; (-1+5)
L1: lda tmp1 ; (39) restore low byte
.endif
rts ; (6502: 45 cycles, 26 bytes <-> 65SC02: 42 cycles, 22 bytes )