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#ifndef U_HALF_H
#define U_HALF_H
#include "pipe/p_compiler.h"
#include "u_math.h"
#ifdef __cplusplus
extern "C" {
#endif
extern uint32_t util_half_to_float_mantissa_table[2048];
extern uint32_t util_half_to_float_exponent_table[64];
extern uint32_t util_half_to_float_offset_table[64];
extern uint16_t util_float_to_half_base_table[512];
extern uint8_t util_float_to_half_shift_table[512];
void util_half_init_tables(void);
/*
* Note that if the half float is a signaling NaN, the x87 FPU will turn
* it into a quiet NaN immediately upon loading into a float.
*
* Additionally, denormals may be flushed to zero.
*
* To avoid this, use the floatui functions instead of the float ones
* when just doing conversion rather than computation on the resulting
* floats.
*/
static INLINE uint32_t
util_half_to_floatui(half h)
{
unsigned exp = h >> 10;
util_half_init_tables();
return util_half_to_float_mantissa_table[util_half_to_float_offset_table[exp] + (h & 0x3ff)]
+ util_half_to_float_exponent_table[exp];
}
static INLINE float
util_half_to_float(half h)
{
union fi r;
util_half_init_tables();
r.ui = util_half_to_floatui(h);
return r.f;
}
static INLINE half
util_floatui_to_half(uint32_t v)
{
unsigned signexp = v >> 23;
util_half_init_tables();
return util_float_to_half_base_table[signexp]
+ ((v & 0x007fffff) >> util_float_to_half_shift_table[signexp]);
}
static INLINE half
util_float_to_half(float f)
{
union fi i;
util_half_init_tables();
i.f = f;
return util_floatui_to_half(i.ui);
}
#ifdef __cplusplus
}
#endif
#endif /* U_HALF_H */
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