F.2.2 Floating-Point Representations

float, double, and long double data elements are represented according to the ISO IEEE 754-1985 standard. The representation is:

(-1)^s(e^- bias⁾¥2 j.f

where:

• s = sign

• e = biased exponent

• j is the leading bit, determined by the value of e. In the case of long double (x86), the leading bit is explicit; in all other cases, it is implicit.

• f = fraction

• u means that the bit can be either 0 or 1.

The following tables show the position of the bits.

Table F–6 float Representation

Bits	Name
31	Sign
23- 30	Exponent
0- 22	Fraction

Table F–7 double Representation

Bits	Name
63	Sign
52- 62	Exponent
0- 51	Fraction

Table F–8 long double Representation (SPARC)

Bits	Name
127	Sign
112- 126	Exponent
0- 111	Fraction

Table F–9 long double Representation (x86)

Bits	Name
80- 95	Unused
79	Sign
64- 78	Exponent
63	Leading bit
0- 62	Fraction

For further information, refer to the Numerical Computation Guide.