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RE: Representation of "double" in powerpc


Hi Ramesh,

The double type on PowerPC with GCC is represented in IEEE 754 fashion.  64 bits "double precision".

SXXXXXXX XXXXIMMMM MMMMMMMM MMMMMMMM MMMMMMMM MMMMMMMM MMMMMMMM MMMMMMMM

S is the 1 sign bit
X is the 11 exponent bits (+1023 biased)
I is the implied (virtual) most-significant bit for normalized numbers
M is the 52 mantissa bits

The order above is byte-by-byte from low memory address to high memory address.

HTH,
--Eljay

http://en.wikipedia.org/wiki/IEEE_754


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