http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49477
Richard Guenther <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2011.06.21 09:48:59
CC| |hubicka at gcc dot gnu.org
Ever Confirmed|0 |1
--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-06-21
09:48:59 UTC ---
Confirmed.
We should
1) disable unneeded optimization at -O0 (we do a lot of folding)
2) look at -O1 (it's basically "untuned" for the last years), make
it the intended "reasonable optimization with good compile-time
and debugging experience" again.
For -O1 my idea was to simply _only_ do early optimizations, thus drop
any IPA optimizations from it and not execute pass_all_optimizations.
In addition to that from early optimizations disable
pass_sra_early, pass_early_ipa_sra and pass_convert_switch. Eventually
insert a DSE pass early (not really sure).
It'll of course change fundamentally what code we emit for -O1, but at
least we have strong CSE/DCE passes and early inlining that is able
to remove C++ abstraction.
Patch that will arrive there half-way (eventually needs fixing so we
still handle some special builtins):
Index: gcc/tree-optimize.c
===================================================================
--- gcc/tree-optimize.c (revision 175205)
+++ gcc/tree-optimize.c (working copy)
@@ -53,7 +53,7 @@ along with GCC; see the file COPYING3.
static bool
gate_all_optimizations (void)
{
- return (optimize >= 1
+ return (optimize > 1
/* Don't bother doing anything if the program has errors.
We have to pass down the queue if we already went into SSA */
&& (!seen_error () || gimple_in_ssa_p (cfun)));
