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Re: Reorganize -ffast-math code.


> > 	* gcc/gcc.c: __FAST_MATH__ does not appear anywhere in the source
> > 	tree, and I can't see the utility of this definition.
> 
> Check on a glibc 2.1+ system <bits/mathinline.h>.  We use some inlines
> if we know that the user has added -ffast-math:
> 
> /* __FAST_MATH__ is defined by gcc -ffast-math.  */
> #ifdef __FAST_MATH__

OK, I just sent a GNAT problem report 

http://gcc.gnu.org/ml/gcc-prs/2001-q1/msg02029.html

that this is not documented; I also included a patch to add the
documentation in that report.

The other substantive change I made that I didn't comment on is that
I changed this comment in simplify-rtx.c

          /* Change division by a constant into multiplication.  Only do
!            this with -ffast-math until an expert says it is safe in
!            general.  */

to

          /* Change division by a constant into multiplication.  Only do
!            this with -funsafe-math-optimizations.  */

since anyone who says it is safe in general is by definition not
an expert :-).  In other words, it isn't safe in general.

All my other changes do not affect either documentation or function
of the compiler

Brad Lucier


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