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Re: libffi & powerpc


Patrick Olinet writes:
 > > > I've compiled again my cross toolchain with the "--with-float=soft"
 > > > option, hoping that it would emulate FPU instruction, but this
 > > > unfortunately doesn't help... I'm nevertheless not sure that this
 > > > option is the right one...
 > >
 > > If your entire toolchain is compiled with --with-float=soft, then you
 > > should use the same options when compiling your code.
 > > >
 > 
 > I thought that fpu emulation worked by trapping cpu exceptions when a
 > fpu instruction is being executed and then emulating this instruction
 > on software level.

Yes.

 > Isn't the mechanism implemented by the "--with-float=soft" option ?

No.  FPU emulation requires no special compile-time options.  The
whole idea is that it runs the same code as native FP.

In contrast, soft-float generates inline subroutine calls for all
floating-point operations.

Andrew.


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