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#ifndef _SDL_bits_h
#define _SDL_bits_h
#include "SDL_stdinc.h"
#include "begin_code.h"
#ifdef __cplusplus
extern "C" {
#endif
SDL_FORCE_INLINE int
SDL_MostSignificantBitIndex32(Uint32 x)
{
#if defined(__GNUC__) && __GNUC__ >= 4
if (x == 0) {
return -1;
}
return 31 - __builtin_clz(x);
#else
const Uint32 b[] = {0x2, 0xC, 0xF0, 0xFF00, 0xFFFF0000};
const int S[] = {1, 2, 4, 8, 16};
int msbIndex = 0;
int i;
if (x == 0) {
return -1;
}
for (i = 4; i >= 0; i--)
{
if (x & b[i])
{
x >>= S[i];
msbIndex |= S[i];
}
}
return msbIndex;
#endif
}
#ifdef __cplusplus
}
#endif
#include "close_code.h"
#endif
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