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[Bug debug/42662] [4.5 Regression] invalid rtl sharing found in the insn



------- Comment #6 from jakub at gcc dot gnu dot org  2010-01-11 09:46 -------
Created an attachment (id=19537)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=19537&action=view)
gcc45-pr42662.patch

Fix.

Regarding the above mentioned patch, it looks like a big hammer, which will
create a lot of garbage.  Are you sure you have investigated where exactly the
sharing originates from?  On the line this patch is fixing XEXP (op0, 0) is
used
twice, once inside the plus and once as the second comparison operand.  So it
is clearly where the bug is introduced.  Another place which also introduces
something similar (x*x scalar floating optimization) already uses properly
copy_rtx.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42662


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