| Message ID | 1342538095.3470.59.camel@gnopaine |
|---|---|
| State | New |
| Headers | show |
On Tue, 17 Jul 2012, William J. Schmidt wrote: > I overlooked adding a pass-control flag for strength reduction, added > here. I named it -ftree-slsr for consistency with other -ftree- flags, > but could change it to -fgimple-slsr if you prefer that for a pass named > gimple-ssa-... > > Bootstrapped and tested on powerpc-unknown-linux-gnu with no new > regressions. Ok for trunk? The switch needs documentation in doc/invoke.texi. Other than that it's fine to stick with -ftree-..., even that exposes details to our users that are not necessary (RTL passes didn't have -frtl-... either). So in the end, why not re-use -fstrength-reduce that is already available (but stubbed out)? Comments from other folks? Thanks, Richard. > Thanks, > Bill > > > 2012-07-17 Bill Schmidt <wschmidt@linux.ibm.com> > > * opts.c (default_option): Make -ftree-slsr default at -O1 and above. > * gimple-ssa-strength-reduction.c (gate_strength_reduction): Use > flag_tree_slsr. > * common.opt: Add -ftree-slsr with flag_tree_slsr. > > > Index: gcc/opts.c > =================================================================== > --- gcc/opts.c (revision 189574) > +++ gcc/opts.c (working copy) > @@ -452,6 +452,7 @@ static const struct default_options default_option > { OPT_LEVELS_1_PLUS, OPT_ftree_ch, NULL, 1 }, > { OPT_LEVELS_1_PLUS, OPT_fcombine_stack_adjustments, NULL, 1 }, > { OPT_LEVELS_1_PLUS, OPT_fcompare_elim, NULL, 1 }, > + { OPT_LEVELS_1_PLUS, OPT_ftree_slsr, NULL, 1 }, > > /* -O2 optimizations. */ > { OPT_LEVELS_2_PLUS, OPT_finline_small_functions, NULL, 1 }, > Index: gcc/gimple-ssa-strength-reduction.c > =================================================================== > --- gcc/gimple-ssa-strength-reduction.c (revision 189574) > +++ gcc/gimple-ssa-strength-reduction.c (working copy) > @@ -1501,7 +1501,7 @@ execute_strength_reduction (void) > static bool > gate_strength_reduction (void) > { > - return optimize > 0; > + return flag_tree_slsr; > } > > struct gimple_opt_pass pass_strength_reduction = > Index: gcc/common.opt > =================================================================== > --- gcc/common.opt (revision 189574) > +++ gcc/common.opt (working copy) > @@ -2080,6 +2080,10 @@ ftree-sink > Common Report Var(flag_tree_sink) Optimization > Enable SSA code sinking on trees > > +ftree-slsr > +Common Report Var(flag_tree_slsr) Optimization > +Perform straight-line strength reduction > + > ftree-sra > Common Report Var(flag_tree_sra) Optimization > Perform scalar replacement of aggregates > > >
On Wed, Jul 18, 2012 at 9:59 AM, Richard Guenther <rguenther@suse.de> wrote: > On Tue, 17 Jul 2012, William J. Schmidt wrote: > >> I overlooked adding a pass-control flag for strength reduction, added >> here. I named it -ftree-slsr for consistency with other -ftree- flags, >> but could change it to -fgimple-slsr if you prefer that for a pass named >> gimple-ssa-... >> >> Bootstrapped and tested on powerpc-unknown-linux-gnu with no new >> regressions. Ok for trunk? > > The switch needs documentation in doc/invoke.texi. Other than that > it's fine to stick with -ftree-..., even that exposes details to our > users that are not necessary (RTL passes didn't have -frtl-... either). > So in the end, why not re-use -fstrength-reduce that is already available > (but stubbed out)? In the past, -fstrength-reduce applied to loop strength reduction in loop.c. I don't think it should be re-used for a completely different code transformation. Ciao! Steven
On Wed, 18 Jul 2012, Steven Bosscher wrote: > On Wed, Jul 18, 2012 at 9:59 AM, Richard Guenther <rguenther@suse.de> wrote: > > On Tue, 17 Jul 2012, William J. Schmidt wrote: > > > >> I overlooked adding a pass-control flag for strength reduction, added > >> here. I named it -ftree-slsr for consistency with other -ftree- flags, > >> but could change it to -fgimple-slsr if you prefer that for a pass named > >> gimple-ssa-... > >> > >> Bootstrapped and tested on powerpc-unknown-linux-gnu with no new > >> regressions. Ok for trunk? > > > > The switch needs documentation in doc/invoke.texi. Other than that > > it's fine to stick with -ftree-..., even that exposes details to our > > users that are not necessary (RTL passes didn't have -frtl-... either). > > So in the end, why not re-use -fstrength-reduce that is already available > > (but stubbed out)? > > In the past, -fstrength-reduce applied to loop strength reduction in > loop.c. I don't think it should be re-used for a completely different > code transformation. Ok. I suppose -ftree-slsr is ok then. Thanks, Richard.
> In the past, -fstrength-reduce applied to loop strength reduction in > loop.c. I don't think it should be re-used for a completely different > code transformation. Seconded.
On Wed, 2012-07-18 at 11:01 +0200, Richard Guenther wrote: > On Wed, 18 Jul 2012, Steven Bosscher wrote: > > > On Wed, Jul 18, 2012 at 9:59 AM, Richard Guenther <rguenther@suse.de> wrote: > > > On Tue, 17 Jul 2012, William J. Schmidt wrote: > > > > > >> I overlooked adding a pass-control flag for strength reduction, added > > >> here. I named it -ftree-slsr for consistency with other -ftree- flags, > > >> but could change it to -fgimple-slsr if you prefer that for a pass named > > >> gimple-ssa-... > > >> > > >> Bootstrapped and tested on powerpc-unknown-linux-gnu with no new > > >> regressions. Ok for trunk? > > > > > > The switch needs documentation in doc/invoke.texi. Other than that > > > it's fine to stick with -ftree-..., even that exposes details to our > > > users that are not necessary (RTL passes didn't have -frtl-... either). > > > So in the end, why not re-use -fstrength-reduce that is already available > > > (but stubbed out)? > > > > In the past, -fstrength-reduce applied to loop strength reduction in > > loop.c. I don't think it should be re-used for a completely different > > code transformation. > > Ok. I suppose -ftree-slsr is ok then. It turns out I was looking at a very old copy of the manual, and the -ftree... stuff is not as prevalent now as it once was. I'll just go with -fslsr to be consistent with -fgcse, -fipa-sra, etc. Thanks for the pointer to doc/invoke.texi -- it appears I also failed to document -fhoist-adjacent-loads, so I will go ahead and do that as well. Thanks! Bill > > Thanks, > Richard. >
On Wed, 2012-07-18 at 08:24 -0500, William J. Schmidt wrote: > On Wed, 2012-07-18 at 11:01 +0200, Richard Guenther wrote: > > On Wed, 18 Jul 2012, Steven Bosscher wrote: > > > > > On Wed, Jul 18, 2012 at 9:59 AM, Richard Guenther <rguenther@suse.de> wrote: > > > > On Tue, 17 Jul 2012, William J. Schmidt wrote: > > > > > > > >> I overlooked adding a pass-control flag for strength reduction, added > > > >> here. I named it -ftree-slsr for consistency with other -ftree- flags, > > > >> but could change it to -fgimple-slsr if you prefer that for a pass named > > > >> gimple-ssa-... > > > >> > > > >> Bootstrapped and tested on powerpc-unknown-linux-gnu with no new > > > >> regressions. Ok for trunk? > > > > > > > > The switch needs documentation in doc/invoke.texi. Other than that > > > > it's fine to stick with -ftree-..., even that exposes details to our > > > > users that are not necessary (RTL passes didn't have -frtl-... either). > > > > So in the end, why not re-use -fstrength-reduce that is already available > > > > (but stubbed out)? > > > > > > In the past, -fstrength-reduce applied to loop strength reduction in > > > loop.c. I don't think it should be re-used for a completely different > > > code transformation. > > > > Ok. I suppose -ftree-slsr is ok then. > > It turns out I was looking at a very old copy of the manual, and the > -ftree... stuff is not as prevalent now as it once was. I'll just go > with -fslsr to be consistent with -fgcse, -fipa-sra, etc. Well, posted too fast. Paging down I see that isn't true, sorry. I'll use the tree- for consistency even though it is useless information. Thanks, Bill > > Thanks for the pointer to doc/invoke.texi -- it appears I also failed to > document -fhoist-adjacent-loads, so I will go ahead and do that as well. > > Thanks! > Bill > > > > > Thanks, > > Richard. > > >
On Wed, Jul 18, 2012 at 3:24 PM, William J. Schmidt <wschmidt@linux.vnet.ibm.com> wrote: > It turns out I was looking at a very old copy of the manual, and the > -ftree... stuff is not as prevalent now as it once was. I'll just go > with -fslsr to be consistent with -fgcse, -fipa-sra, etc. Sadly, it is more prevalent than it ever was! It's IMHO very unfortunate that such an internal detail is exposed to the user... Ciao! Steven
On Wed, 18 Jul 2012, Steven Bosscher wrote: > On Wed, Jul 18, 2012 at 3:24 PM, William J. Schmidt > <wschmidt@linux.vnet.ibm.com> wrote: > > It turns out I was looking at a very old copy of the manual, and the > > -ftree... stuff is not as prevalent now as it once was. I'll just go > > with -fslsr to be consistent with -fgcse, -fipa-sra, etc. > > Sadly, it is more prevalent than it ever was! > It's IMHO very unfortunate that such an internal detail is exposed to > the user... Indeed... not sure if we want a set of aliases without the tree- or rtl- part. Richard.
Index: gcc/opts.c =================================================================== --- gcc/opts.c (revision 189574) +++ gcc/opts.c (working copy) @@ -452,6 +452,7 @@ static const struct default_options default_option { OPT_LEVELS_1_PLUS, OPT_ftree_ch, NULL, 1 }, { OPT_LEVELS_1_PLUS, OPT_fcombine_stack_adjustments, NULL, 1 }, { OPT_LEVELS_1_PLUS, OPT_fcompare_elim, NULL, 1 }, + { OPT_LEVELS_1_PLUS, OPT_ftree_slsr, NULL, 1 }, /* -O2 optimizations. */ { OPT_LEVELS_2_PLUS, OPT_finline_small_functions, NULL, 1 }, Index: gcc/gimple-ssa-strength-reduction.c =================================================================== --- gcc/gimple-ssa-strength-reduction.c (revision 189574) +++ gcc/gimple-ssa-strength-reduction.c (working copy) @@ -1501,7 +1501,7 @@ execute_strength_reduction (void) static bool gate_strength_reduction (void) { - return optimize > 0; + return flag_tree_slsr; } struct gimple_opt_pass pass_strength_reduction = Index: gcc/common.opt =================================================================== --- gcc/common.opt (revision 189574) +++ gcc/common.opt (working copy) @@ -2080,6 +2080,10 @@ ftree-sink Common Report Var(flag_tree_sink) Optimization Enable SSA code sinking on trees +ftree-slsr +Common Report Var(flag_tree_slsr) Optimization +Perform straight-line strength reduction + ftree-sra Common Report Var(flag_tree_sra) Optimization Perform scalar replacement of aggregates