]> git.zerfleddert.de Git - proxmark3-svn/blob - common/parity.h
optimization UDOL creation. does not affect on functionality.
[proxmark3-svn] / common / parity.h
1 //-----------------------------------------------------------------------------
2 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
3 // at your option, any later version. See the LICENSE.txt file for the text of
4 // the license.
5 //-----------------------------------------------------------------------------
6 // Parity functions
7 //-----------------------------------------------------------------------------
8
9 // all functions defined in header file by purpose. Allows compiler optimizations.
10
11 #ifndef __PARITY_H
12 #define __PARITY_H
13
14 #include <stdint.h>
15 #include <stdbool.h>
16
17 extern const uint8_t OddByteParity[256];
18
19
20 static inline bool oddparity8(const uint8_t x) {
21 return OddByteParity[x];
22 }
23
24
25 static inline bool evenparity8(const uint8_t x) {
26 return !OddByteParity[x];
27 }
28
29
30 static inline bool evenparity32(uint32_t x)
31 {
32 #if !defined __GNUC__
33 x ^= x >> 16;
34 x ^= x >> 8;
35 return evenparity8(x);
36 #else
37 return __builtin_parity(x);
38 #endif
39 }
40
41
42 static inline bool oddparity32(uint32_t x)
43 {
44 #if !defined __GNUC__
45 x ^= x >> 16;
46 x ^= x >> 8;
47 return oddparity8(x);
48 #else
49 return !__builtin_parity(x);
50 #endif
51 }
52
53 #endif /* __PARITY_H */
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