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36 brw_float_to_vf(float f
)
38 union fu fu
= { .f
= f
};
40 /* ±0.0f is special cased. */
42 return fu
.s
.sign
<< 7;
44 unsigned mantissa
= fu
.s
.mantissa
>> (23 - 4);
45 unsigned exponent
= fu
.s
.exponent
- (127 - 3);
46 unsigned vf
= (fu
.s
.sign
<< 7) | (exponent
<< 4) | mantissa
;
48 /* 0.125 would have had the same representation as 0.0, so reject it. */
52 /* Make sure the mantissa fits in 4-bits and the exponent in 3-bits. */
53 if (fu
.u
& 0x7ffff || exponent
> 7)
60 brw_vf_to_float(unsigned char vf
)
64 /* ±0.0f is special cased. */
65 if (vf
== 0x00 || vf
== 0x80) {
71 fu
.s
.exponent
= ((vf
& 0x70) >> 4) + (127 - 3);
72 fu
.s
.mantissa
= (vf
& 0xf) << (23 - 4);