GPGPU Programming for Games and Science

80 GPGPU Programming for Games and Science

{

// N e a r e s t i s NAR−zero .

return signNAR ;

}

if (nonnegWID <=WID

NAR MIN SUBNORMAL)

{

// N e a r e s t i s NAR−min−subnormal .

return signNAR | NAR

MIN SUBNORMAL ;

}

if (nonnegWID < WID

NAR MIN NORMAL)

{

// Round to ne a res t NAR−subnormal with ties −to−even . Note

// t h a t bi asedN AR i s i mp l i c i t ly z e r o .

trailingWID |=WID

SUP TRAILING MASK ;

rshift = WID

NUM TRAILING BITS − NAR NUM TRAIL ING BITS +

WID

EXPONENT BIAS − NAR EXPONENT BIAS + 1 − biasedWID ;

trailingNAR = ( trailingWID >> rshift );

lshift = WID

NUM ENCODING BITS − rshift ;

frcpart = (trailingWID << lshift );

if (frcpart > WID

HALF PROXY

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