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Optimised strlen

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Polluks 2021-05-08 18:23:19 +02:00 committed by Oliver Schmidt
parent 3ea330f15f
commit 4c37f12a4d
1 changed files with 11 additions and 1 deletions
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12
libsrc/common/strlen.s
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@ -5,17 +5,27 @@
; the usage of only ptr2 here! Keep in mind when appling changes ; the usage of only ptr2 here! Keep in mind when appling changes
; and check the other implementations too! ; and check the other implementations too!
; ;
; int strlen (const char* s); ; size_t __fastcall__ strlen (const char* s);
; ;
.export _strlen .export _strlen
.importzp ptr2 .importzp ptr2
.macpack cpu
_strlen: _strlen:
sta ptr2 ; Save s sta ptr2 ; Save s
stx ptr2+1 stx ptr2+1
.if (.cpu .bitand ::CPU_ISET_HUC6280)
clx
cly
.else
ldx #0 ; YX used as counter ldx #0 ; YX used as counter
.if (.cpu .bitand ::CPU_ISET_65816)
txy
.else
ldy #0 ldy #0
.endif
.endif
L1: lda (ptr2),y L1: lda (ptr2),y
beq L9 beq L9