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Re: More DOM memory reductions
On Tue, 2004-09-21 at 08:31, Jan Hubicka wrote:
> Just for a record, gcctest reported following savings on Gerald's
> testcase:
> Amount of produced GGC garbage decreased from 730435k to 696554k, overall -4.86%
I'm not measuring garbage, but the amount of GC memory allocated.
It's always possible I read the result incorrectly.
> I am also very surprised by zero effect of this patch on combine.c
> memory usage....
Gerald's testcase has the interesting property that it has a huge
number of jumps that can be threaded, which in turn can cause the
generation of new SSA_NAMEs and iteration of DOM, which in turn
causes us to grow the const_and_copies varray.
Combine has threading opportunities, but it could easily be the
case that the new SSA_NAMEs needed in those cases can be satisfied
by the freelist or by increasing the size of the existing
const_and_copies without rellocating it.
jeff