On 06/24/14 14:19, Martin Jambor wrote:
On Mon, Jun 23, 2014 at 03:35:01PM +0200, Bernd Edlinger wrote:
Hi Martin,
Well actually, I am not sure if we ever wanted to have a race condition here.
Have you seen any impact of --param allow-store-data-races on any benchmark?
It's trivially to write one. The only pass that checks the param is
tree loop invariant motion and it does that when it applies store-motion.
Register pressure increase is increased by a factor of two.
So I'd agree that we might want to disable this again for -Ofast.
As nothing tests for the PACKED variants nor for the LOAD variant
I'd rather remove those. Claiming we don't create races for those
when you disable it via the param is simply not true.
Thanks,
Richard.
OK, please go ahead with your patch.
Perhaps not unsurprisingly, the patch is very similar. Bootstrapped
and tested on x86_64-linux. OK for trunk?
Thanks,
Martin
2014-06-24 Martin Jambor <mjam...@suse.cz>
* params.def (PARAM_ALLOW_LOAD_DATA_RACES)
(PARAM_ALLOW_PACKED_LOAD_DATA_RACES)
(PARAM_ALLOW_PACKED_STORE_DATA_RACES): Removed.
(PARAM_ALLOW_STORE_DATA_RACES): Set default to zero.
* opts.c (default_options_optimization): Set
PARAM_ALLOW_STORE_DATA_RACES to one at -Ofast.
* doc/invoke.texi (allow-load-data-races)
(allow-packed-load-data-races, allow-packed-store-data-races):
Removed.
(allow-store-data-races): Document the new default.
testsuite/
* g++.dg/simulate-thread/bitfields-2.C: Remove allow-load-data-races
parameter.
* g++.dg/simulate-thread/bitfields.C: Likewise.
* gcc.dg/simulate-thread/strict-align-global.c: Remove
allow-packed-store-data-races parameter.
* gcc.dg/simulate-thread/subfields.c: Likewise.
* gcc.dg/tree-ssa/20050314-1.c: Set parameter allow-store-data-races
to one.
Don't we want to deprecate, not remove the dead options?
Jeff
