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for me as memcpy did. Check out inc/utils.h, since this Duff's device is implemented as a macro which could be used for unrolling other loops selectively.
36 lines
1.1 KiB
C
36 lines
1.1 KiB
C
// General purpose function/macros
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#ifndef __UTILS_H__
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#define __UTILS_H__
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#define ABSDIFF( x, y ) ( ( x ) >= ( y ) ? ( x ) - ( y ) : ( y ) - ( x ) )
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#define UMIN( x, y ) ( ( x ) <= ( y ) ? ( x ) : ( y ) )
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#define UMAX( x, y ) ( ( x ) >= ( y ) ? ( x ) : ( y ) )
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#define UABS( x ) ( ( x ) >= 0 ? ( x ) : -( x ) )
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// Macro version of Duff's device found in
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// "A Reusable Duff Device" by Ralf Holly
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// Dr Dobb's Journal, August 1, 2005
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#define DUFF_DEVICE_8(count, action) \
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do { \
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int _count = ( count ); \
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int _times = ( _count + 7 ) >> 3; \
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switch ( _count & 7 ){ \
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case 0: do { action; \
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case 7: action; \
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case 6: action; \
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case 5: action; \
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case 4: action; \
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case 3: action; \
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case 2: action; \
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case 1: action; \
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} while (--_times > 0); \
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} \
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} while (0)
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#define STD_CTRLZ_CODE 26
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#endif
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