Pranav Bhandarkar wrote:
Hi,
In the attached testcase due to an ivopts modification, while
rewriting the uses the compiler crashes in tree-ssa-operands.c because
the number of virtual operands of the modified stmt is much greater
than the thresholds controlled by OP_SIZE_{1,2,3} in
tree-ssa-operands.c.
I went through
http://gcc.gnu.org/ml/gcc-patches/2006-12/msg01269.html
and it seemed to me that these values (OP_SIZE etc) have been quite
experimentally set. I am wondering If these values should be
increased.
They are 'experimental', but the reason is to catch cases like this to
examine. MEM-SSA was suppose to eliminate excessively large numbers of
virtual operands. I haven't had a chance to look at this yet, perhaps
Diego will get a chance before I do since I'm traveling and tied up the
rest of this week.
If it turns out there isn't something mem-ssa should be doing
differently for this case to reduce the number of operands, we can
either increase the thresholds, or add a 4th one for these excessive
cases. Im hoping there is a different solution since large numbers of
virtuals cause lots of compile time issues. I believe the previous times
we've triggered this (Its been a while), we made changes to the virtual
operand processing to resolve it and save memory/compile time.
Andrew