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help with the conception of floating point
- From: Eric Fisher <joefoxreal at gmail dot com>
- To: gcc at gcc dot gnu dot org
- Date: Fri, 20 Jan 2006 14:18:05 +0800
- Subject: help with the conception of floating point
I guess that the macro NGARDS is relevant to the guard digit. But I
still failed to have a clear conception about what it means. Others
are easy to know by IEEE 754 and "What Every Computer Scientist Should
Know about Floating-Point Arithmetic". Except,
define NGARDS 8L
define GARDROUND 0x7f
define GARDMASK 0xff
define GARDMSB 0x80
what do these mean? :-)
Especially when unpack a signal floating point, the fraction takes
such an operation at last, that make me much confused.
dst->fraction.ll = (fraction << NGARDS) | IMPLICIT_1;
I just want to know what does this mean.:-)
Thanks a lot.
Eirc.