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Re: Patch to allow Ada to work with tree-ssa


On Tue, 22 Jun 2004, Mark Mitchell wrote:

> No, we can't.  It is precisely the 1% increases that have gotten us to 
> the bloated state we are in now.  A patch a week with a 1% increase 
> means that we get close to doubling the memory usage every year.  I just 

As dramatically illustrated (not quite doubling every year, but still
excessive) in bug 15678, which has benchmarks back to GCC 1.27.  A
testcase given built at -O0 in 0.92s and 8MB memory with GCC 1.27
(released 1988-09-05) and 19.9s and 169MB memory with mainline of
2004-05-26.  Both have increased by a factor of between 21 and 22 in 5742
days.  A 1% increase every 18 days suffices to explain this.  What we do
at -O0 should not be 20 times as complicated as what GCC 1.27 did at -O0.
(That test is simply 32768 empty functions.  I've no reason to suppose
things are different for real code.)

-- 
Joseph S. Myers               http://www.srcf.ucam.org/~jsm28/gcc/
    jsm@polyomino.org.uk (personal mail)
    jsm28@gcc.gnu.org (Bugzilla assignments and CCs)


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