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ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
27 |
POSSIBILITY OF SUCH DAMAGE. */ |
POSSIBILITY OF SUCH DAMAGE. */ |
28 |
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29 |
|
/* $Id$ */ |
30 |
|
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31 |
#include "macros.inc" |
#include "macros.inc" |
32 |
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|
33 |
#define src_hi r25 |
#define src_hi r25 |
54 |
.global _U(strnlen) |
.global _U(strnlen) |
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.type _U(strnlen), @function |
.type _U(strnlen), @function |
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_U(strnlen): |
_U(strnlen): |
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LOAD_Z(src_lo, src_hi) |
X_movw ZL, src_lo |
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.strnlen_loop: |
.L_strnlen_loop: |
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subi len_lo, lo8(1) |
subi len_lo, lo8(1) |
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sbci len_hi, hi8(1) |
sbci len_hi, hi8(1) |
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ld __tmp_reg__, Z+ |
ld __tmp_reg__, Z+ |
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cpse __tmp_reg__, __zero_reg__ |
cpse __tmp_reg__, __zero_reg__ |
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brcc .strnlen_loop |
brcc .L_strnlen_loop |
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; Z points one character past the terminating NUL |
; Z points one character past the terminating NUL |
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; return Z - 1 - src = (-1 - src) + Z = ~src + Z |
; return Z - 1 - src = (-1 - src) + Z = ~src + Z |
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com src_lo |
com src_lo |
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add src_lo, ZL |
add src_lo, ZL |
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adc src_hi, ZH |
adc src_hi, ZH |
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ret |
ret |
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.strnlen_end: |
.L_strnlen_end: |
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.size _U(strnlen), .strnlen_end - _U(strnlen) |
.size _U(strnlen), .L_strnlen_end - _U(strnlen) |
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#endif /* not __DOXYGEN__ */ |
#endif /* not __DOXYGEN__ */ |