PATCH to reduce memory usage ofdelete_null_pointer_checks

[Mark Mitchell]

>>>>> "Jeffrey" == Jeffrey A Law <law@cygnus.com> writes:

    Jeffrey> Don't leave us hanging is suspense.  How big of a
    Jeffrey> difference did it make :-)

Sorry.  About 10-12% on most test-cases.  But, it's really more than
that; we're only seeing a reduction in peak usage by about 10-12%
because of the fact that the space that would have been used by
null-pointer checking is still getting filled up later in the
compilation by the bodies of various inlined functions.

The patch limits memory usage by the null-pointer checking pass to
about 10MB.  Before it was using 150MB.

--
Mark Mitchell                   mark@codesourcery.com
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