struct / union in initializer, RFE #901.
[sdcc.git] / sdcc / device / lib / z80 / memcpy.s
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1 ;--------------------------------------------------------------------------
2 ; memcpy.s
4 ; Copyright (C) 2020, Sergey Belyashov
5 ; Copyright (c) 2021, Philipp Klaus Krause
7 ; This library is free software; you can redistribute it and/or modify it
8 ; under the terms of the GNU General Public License as published by the
9 ; Free Software Foundation; either version 2, or (at your option) any
10 ; later version.
12 ; This library is distributed in the hope that it will be useful,
13 ; but WITHOUT ANY WARRANTY; without even the implied warranty of
14 ; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 ; GNU General Public License for more details.
17 ; You should have received a copy of the GNU General Public License
18 ; along with this library; see the file COPYING. If not, write to the
19 ; Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
20 ; MA 02110-1301, USA.
22 ; As a special exception, if you link this library with other files,
23 ; some of which are compiled with SDCC, to produce an executable,
24 ; this library does not by itself cause the resulting executable to
25 ; be covered by the GNU General Public License. This exception does
26 ; not however invalidate any other reasons why the executable file
27 ; might be covered by the GNU General Public License.
28 ;--------------------------------------------------------------------------
30 .module memcpy
31 .optsdcc -mz80 sdcccall(1)
33 .area _CODE
35 .globl _memcpy
36 .globl ___memcpy
38 ; The Z80 has the ldir instruction, which is perfect for implementing memcpy().
39 _memcpy:
40 ___memcpy:
41 ex de, hl
42 pop iy
43 pop bc
44 ld a, c
45 or a, b
46 jr Z, end
47 push de
48 ldir
49 pop de
50 end:
51 jp (iy)