cc65/libsrc/common/isalpha.s

22 lines
523 B
ArmAsm

; isalpha.s
;
; This file is part of
; cc65 - a freeware C compiler for 6502 based systems
;
; https://cc65.github.io
;
; See "LICENSE" file for legal information.
;
; int isalpha (int c);
;
.export _isalpha
.include "ctype.inc"
.import ctypemask
_isalpha:
jsr ctypemask ; (always clears X)
bcs @L1 ; out of range? (everything already clear -> false)
and #CT_ALPHA ; mask character bits
@L1: rts