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(svn r11378) -Codechange: optimize KillFirstBit2x64 (skidd13)
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11
src/macros.h
11
src/macros.h
@ -416,21 +416,14 @@ Faster ( or at least cleaner ) implementation below?
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* Clear the first bit in an integer.
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*
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* This function returns a value where the first bit (from LSB)
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* is cleared. This function checks, similar to FindFirstBit2x64,
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* the bits at 0x3F3F.
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* is cleared. This function checks only the bits of 0x3F3F!
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*
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* @param value The value to clear the first bit
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* @return The new value with the first bit cleared
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* @see KILL_FIRST_BIT
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* @see FindFirstBit2x64
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*/
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static inline int KillFirstBit2x64(int value)
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{
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if (GB(value, 0, 8) == 0) {
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return KILL_FIRST_BIT(GB(value, 8, 6)) << 8;
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} else {
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return value & (KILL_FIRST_BIT(GB(value, 0, 6)) | 0x3F00);
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}
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return value &= (int)(value - 1) | 0x3FFFC0C0;
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}
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/**
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