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#include "MachDeps.h"
#include "Rts.h"
#include <stdint.h>
// Fall-back implementations for count-leading-zeros primop
//
// __builtin_clz*() is supported by GCC and Clang
#if SIZEOF_UNSIGNED_INT == 4
StgWord
hs_clz8(StgWord x)
{
return (uint8_t)x ? __builtin_clz((uint8_t)x)-24 : 8;
}
StgWord
hs_clz16(StgWord x)
{
return (uint16_t)x ? __builtin_clz((uint16_t)x)-16 : 16;
}
StgWord
hs_clz32(StgWord x)
{
return (uint32_t)x ? __builtin_clz((uint32_t)x) : 32;
}
#else
# error no suitable __builtin_clz() found
#endif
StgWord
hs_clz64(StgWord64 x)
{
#if SIZEOF_UNSIGNED_LONG == 8
return x ? __builtin_clzl(x) : 64;
#elif SIZEOF_UNSIGNED_LONG_LONG == 8
return x ? __builtin_clzll(x) : 64;
#else
# error no suitable __builtin_clz() found
#endif
}
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