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Re: [lno] [RFC] if-conversion and auto vectorizer

Richard Henderson wrote:

On Tue, Mar 16, 2004 at 11:55:59PM +0100, Toon Moene wrote:

No valid (Fortran) program can cause the generation of floating point exceptions or memory access violations ? 

I think you're missing the point.  Valid Fortran programs perform
checks to see if particular operations may or should be evaluated.  E.g.

	if (y .eq. 0.) then
	  z = 0
	else
	  z = x / y
	endif

What Devang is proposing is to MOVE the test, creating (more or less)

Ah, yes, that would convert a valid Fortran program into an invalid one.

Thanks for the explanation.

--
Toon Moene - mailto:toon@moene.indiv.nluug.nl - phoneto: +31 346 214290
Saturnushof 14, 3738 XG  Maartensdijk, The Netherlands
Maintainer, GNU Fortran 77: http://gcc.gnu.org/onlinedocs/g77_news.html
GNU Fortran 95: http://gcc.gnu.org/fortran/ (under construction)

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