On 26 December 2010 23:32, Andreas Raab andreas.raab@gmx.de wrote:
On 12/26/2010 10:19 PM, Igor Stasenko wrote:
low level C code which pretending to know how to do it 'right' + C compiler , who also knowing how to do it 'right' ===>> mess in result :)
Well, I'm sorry but the C code does bit manipulation according to IEEE 754 so it's hard to blame that code for overly aggressive gcc optimizations. FWIW, the FloatMathPlugin must also be compiled with -mno-fused-madd as this would produce another source of differences depending on whether a compiler chooses to use fmadd or not.
ok. added :)
Btw, i found another library: http://www.jhauser.us/arithmetic/SoftFloat.html
looks like this one don't have problems with gcc -O2, because at "SoftFloat speed" it says that it is compiled with this option.
Cheers, - Andreas