| Message ID | 20221119062532.75190-1-hongyu.wang@intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | i386: Only enable small loop unrolling in backend [PR 107602] | expand |
> -----Original Message----- > From: Wang, Hongyu <hongyu.wang@intel.com> > Sent: Saturday, November 19, 2022 2:26 PM > To: gcc-patches@gcc.gnu.org > Cc: richard.guenther@gmail.com; ubizjak@gmail.com; Liu, Hongtao > <hongtao.liu@intel.com> > Subject: [PATCH] i386: Only enable small loop unrolling in backend [PR 107602] > > Hi, > > Followed by the discussion in pr107602, -munroll-only-small-loops Does not PR107692? > turns on/off -funroll-loops, and current check in pass_rtl_unroll_loops::gate > would cause -funroll-loops do not take effect. Revert the change about > targetm.loop_unroll_adjust and apply the backend option change to strictly > follow the rule that -funroll-loops takes full control of loop unrolling, and > munroll-only-small-loops just change its behavior to unroll small size loops. > > Bootstrapped and regtested on x86-64-pc-linux-gnu. > > Ok for trunk? > > gcc/ChangeLog: > > PR target/107602 > * common/config/i386/i386-common.cc (ix86_optimization_table): > Enable loop unroll O2, disable -fweb and -frename-registers > by default. > * config/i386/i386-options.cc > (ix86_override_options_after_change): > Disable small loop unroll when funroll-loops enabled, reset > cunroll_grow_size when it is not explicitly enabled. > (ix86_option_override_internal): Call > ix86_override_options_after_change instead of calling > ix86_recompute_optlev_based_flags and ix86_default_align > separately. > * config/i386/i386.cc (ix86_loop_unroll_adjust): Adjust unroll > factor if -munroll-only-small-loops enabled. > * loop-init.cc (pass_rtl_unroll_loops::gate): Do not enable > loop unrolling for -O2-speed. > (pass_rtl_unroll_loops::execute): Rmove > targetm.loop_unroll_adjust check. > > gcc/testsuite/ChangeLog: > > PR target/107602 > * gcc.target/i386/pr86270.c: Add -fno-unroll-loops. > * gcc.target/i386/pr93002.c: Likewise. > --- > gcc/common/config/i386/i386-common.cc | 8 ++++++ > gcc/config/i386/i386-options.cc | 34 ++++++++++++++++++++++--- > gcc/config/i386/i386.cc | 18 ++++--------- > gcc/loop-init.cc | 11 +++----- > gcc/testsuite/gcc.target/i386/pr86270.c | 2 +- > gcc/testsuite/gcc.target/i386/pr93002.c | 2 +- > 6 files changed, 49 insertions(+), 26 deletions(-) > > diff --git a/gcc/common/config/i386/i386-common.cc > b/gcc/common/config/i386/i386-common.cc > index 6ce2a588adc..660a977b68b 100644 > --- a/gcc/common/config/i386/i386-common.cc > +++ b/gcc/common/config/i386/i386-common.cc > @@ -1808,7 +1808,15 @@ static const struct default_options > ix86_option_optimization_table[] = > /* The STC algorithm produces the smallest code at -Os, for x86. */ > { OPT_LEVELS_2_PLUS, OPT_freorder_blocks_algorithm_, NULL, > REORDER_BLOCKS_ALGORITHM_STC }, > + > + /* Turn on -funroll-loops with -munroll-only-small-loops to enable small > + loop unrolling at -O2. */ > + { OPT_LEVELS_2_PLUS_SPEED_ONLY, OPT_funroll_loops, NULL, 1 }, > { OPT_LEVELS_2_PLUS_SPEED_ONLY, OPT_munroll_only_small_loops, NULL, > 1 }, > + /* Turns off -frename-registers and -fweb which are enabled by > + funroll-loops. */ > + { OPT_LEVELS_ALL, OPT_frename_registers, NULL, 0 }, > + { OPT_LEVELS_ALL, OPT_fweb, NULL, 0 }, > /* Turn off -fschedule-insns by default. It tends to make the > problem with not enough registers even worse. */ > { OPT_LEVELS_ALL, OPT_fschedule_insns, NULL, 0 }, diff --git > a/gcc/config/i386/i386-options.cc b/gcc/config/i386/i386-options.cc index > e5c77f3a84d..bc1d36e36a8 100644 > --- a/gcc/config/i386/i386-options.cc > +++ b/gcc/config/i386/i386-options.cc > @@ -1838,8 +1838,37 @@ ix86_recompute_optlev_based_flags (struct > gcc_options *opts, void ix86_override_options_after_change (void) { > + /* Default align_* from the processor table. */ > ix86_default_align (&global_options); > + > ix86_recompute_optlev_based_flags (&global_options, &global_options_set); > + > + /* Disable unrolling small loops when there's explicit > + -f{,no}unroll-loop. */ > + if ((OPTION_SET_P (flag_unroll_loops)) > + || (OPTION_SET_P (flag_unroll_all_loops) > + && flag_unroll_all_loops)) > + { > + if (!OPTION_SET_P (ix86_unroll_only_small_loops)) > + ix86_unroll_only_small_loops = 0; > + /* Re-enable -frename-registers and -fweb if funroll-loops > + enabled. */ > + if (!OPTION_SET_P (flag_web)) > + flag_web = flag_unroll_loops; > + if (!OPTION_SET_P (flag_rename_registers)) > + flag_rename_registers = flag_unroll_loops; > + /* -fcunroll-grow-size default follws -f[no]-unroll-loops. */ > + if (!OPTION_SET_P (flag_cunroll_grow_size)) > + flag_cunroll_grow_size = flag_unroll_loops > + || flag_peel_loops > + || optimize >= 3; > + } > + else > + { > + if (!OPTION_SET_P (flag_cunroll_grow_size)) > + flag_cunroll_grow_size = flag_peel_loops || optimize >= 3; > + } > + > } > > /* Clear stack slot assignments remembered from previous functions. > @@ -2351,7 +2380,7 @@ ix86_option_override_internal (bool main_args_p, > > set_ix86_tune_features (opts, ix86_tune, opts->x_ix86_dump_tunes); > > - ix86_recompute_optlev_based_flags (opts, opts_set); > + ix86_override_options_after_change (); > > ix86_tune_cost = processor_cost_table[ix86_tune]; > /* TODO: ix86_cost should be chosen at instruction or function granuality > @@ -2382,9 +2411,6 @@ ix86_option_override_internal (bool main_args_p, > || TARGET_64BIT_P (opts->x_ix86_isa_flags)) > opts->x_ix86_regparm = REGPARM_MAX; > > - /* Default align_* from the processor table. */ > - ix86_default_align (opts); > - > /* Provide default for -mbranch-cost= value. */ > SET_OPTION_IF_UNSET (opts, opts_set, ix86_branch_cost, > ix86_tune_cost->branch_cost); > diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc index > 292b32c5e99..10f8b4e91a5 100644 > --- a/gcc/config/i386/i386.cc > +++ b/gcc/config/i386/i386.cc > @@ -23829,20 +23829,12 @@ ix86_loop_unroll_adjust (unsigned nunroll, > class loop *loop) > > /* Unroll small size loop when unroll factor is not explicitly > specified. */ > - if (!(flag_unroll_loops > - || flag_unroll_all_loops > - || loop->unroll)) > + if (ix86_unroll_only_small_loops && !loop->unroll) > { > - nunroll = 1; > - > - /* Any explicit -f{no-}unroll-{all-}loops turns off > - -munroll-only-small-loops. */ > - if (ix86_unroll_only_small_loops > - && !OPTION_SET_P (flag_unroll_loops) > - && loop->ninsns <= ix86_cost->small_unroll_ninsns) > - nunroll = ix86_cost->small_unroll_factor; > - > - return nunroll; > + if (loop->ninsns <= ix86_cost->small_unroll_ninsns) > + return MIN (nunroll, ix86_cost->small_unroll_factor); > + else > + return 1; > } > > if (!TARGET_ADJUST_UNROLL) > diff --git a/gcc/loop-init.cc b/gcc/loop-init.cc index 9789efa1e11..f03c077cae1 > 100644 > --- a/gcc/loop-init.cc > +++ b/gcc/loop-init.cc > @@ -565,12 +565,10 @@ public: > {} > > /* opt_pass methods: */ > - bool gate (function *fun) final override > + bool gate (function *) final override > { > - return (flag_unroll_loops || flag_unroll_all_loops || cfun->has_unroll > - || (targetm.loop_unroll_adjust > - && optimize >= 2 > - && optimize_function_for_speed_p (fun))); > + return (flag_unroll_loops || flag_unroll_all_loops > + || cfun->has_unroll); > } > > unsigned int execute (function *) final override; @@ -586,8 +584,7 @@ > pass_rtl_unroll_loops::execute (function *fun) > if (dump_file) > df_dump (dump_file); > > - if (flag_unroll_loops > - || targetm.loop_unroll_adjust) > + if (flag_unroll_loops) > flags |= UAP_UNROLL; > if (flag_unroll_all_loops) > flags |= UAP_UNROLL_ALL; > diff --git a/gcc/testsuite/gcc.target/i386/pr86270.c > b/gcc/testsuite/gcc.target/i386/pr86270.c > index cbc9fbb0450..98b012caf23 100644 > --- a/gcc/testsuite/gcc.target/i386/pr86270.c > +++ b/gcc/testsuite/gcc.target/i386/pr86270.c > @@ -1,5 +1,5 @@ > /* { dg-do compile } */ > -/* { dg-options "-O2 -mno-unroll-only-small-loops" } */ > +/* { dg-options "-O2 -fno-unroll-loops" } */ > > int *a; > long len; > diff --git a/gcc/testsuite/gcc.target/i386/pr93002.c > b/gcc/testsuite/gcc.target/i386/pr93002.c > index f75a847f75d..7e2d869e17b 100644 > --- a/gcc/testsuite/gcc.target/i386/pr93002.c > +++ b/gcc/testsuite/gcc.target/i386/pr93002.c > @@ -1,6 +1,6 @@ > /* PR target/93002 */ > /* { dg-do compile } */ > -/* { dg-options "-O2 -mno-unroll-only-small-loops" } */ > +/* { dg-options "-O2 -fno-unroll-loops" } */ > /* { dg-final { scan-assembler-not "cmp\[^\n\r]*-1" } } */ > > volatile int sink; > -- > 2.18.1
On Mon, Nov 21, 2022 at 9:01 AM Liu, Hongtao via Gcc-patches <gcc-patches@gcc.gnu.org> wrote: > > > > > -----Original Message----- > > From: Wang, Hongyu <hongyu.wang@intel.com> > > Sent: Saturday, November 19, 2022 2:26 PM > > To: gcc-patches@gcc.gnu.org > > Cc: richard.guenther@gmail.com; ubizjak@gmail.com; Liu, Hongtao > > <hongtao.liu@intel.com> > > Subject: [PATCH] i386: Only enable small loop unrolling in backend [PR 107602] > > > > Hi, > > > > Followed by the discussion in pr107602, -munroll-only-small-loops Does not > PR107692? > > turns on/off -funroll-loops, and current check in pass_rtl_unroll_loops::gate > > would cause -funroll-loops do not take effect. Revert the change about It's not necessarily right. unroll_factor will be set as 1 when -fno-unroll-loops, which is exactly -fno-unroll-loops means. > > targetm.loop_unroll_adjust and apply the backend option change to strictly > > follow the rule that -funroll-loops takes full control of loop unrolling, and > > munroll-only-small-loops just change its behavior to unroll small size loops. > > > > Bootstrapped and regtested on x86-64-pc-linux-gnu. > > > > Ok for trunk? > > > > gcc/ChangeLog: > > > > PR target/107602 > > * common/config/i386/i386-common.cc (ix86_optimization_table): > > Enable loop unroll O2, disable -fweb and -frename-registers > > by default. > > * config/i386/i386-options.cc > > (ix86_override_options_after_change): > > Disable small loop unroll when funroll-loops enabled, reset > > cunroll_grow_size when it is not explicitly enabled. > > (ix86_option_override_internal): Call > > ix86_override_options_after_change instead of calling > > ix86_recompute_optlev_based_flags and ix86_default_align > > separately. > > * config/i386/i386.cc (ix86_loop_unroll_adjust): Adjust unroll > > factor if -munroll-only-small-loops enabled. > > * loop-init.cc (pass_rtl_unroll_loops::gate): Do not enable > > loop unrolling for -O2-speed. > > (pass_rtl_unroll_loops::execute): Rmove > > targetm.loop_unroll_adjust check. > > > > gcc/testsuite/ChangeLog: > > > > PR target/107602 > > * gcc.target/i386/pr86270.c: Add -fno-unroll-loops. > > * gcc.target/i386/pr93002.c: Likewise. > > --- > > gcc/common/config/i386/i386-common.cc | 8 ++++++ > > gcc/config/i386/i386-options.cc | 34 ++++++++++++++++++++++--- > > gcc/config/i386/i386.cc | 18 ++++--------- > > gcc/loop-init.cc | 11 +++----- > > gcc/testsuite/gcc.target/i386/pr86270.c | 2 +- > > gcc/testsuite/gcc.target/i386/pr93002.c | 2 +- > > 6 files changed, 49 insertions(+), 26 deletions(-) > > > > diff --git a/gcc/common/config/i386/i386-common.cc > > b/gcc/common/config/i386/i386-common.cc > > index 6ce2a588adc..660a977b68b 100644 > > --- a/gcc/common/config/i386/i386-common.cc > > +++ b/gcc/common/config/i386/i386-common.cc > > @@ -1808,7 +1808,15 @@ static const struct default_options > > ix86_option_optimization_table[] = > > /* The STC algorithm produces the smallest code at -Os, for x86. */ > > { OPT_LEVELS_2_PLUS, OPT_freorder_blocks_algorithm_, NULL, > > REORDER_BLOCKS_ALGORITHM_STC }, > > + > > + /* Turn on -funroll-loops with -munroll-only-small-loops to enable small > > + loop unrolling at -O2. */ > > + { OPT_LEVELS_2_PLUS_SPEED_ONLY, OPT_funroll_loops, NULL, 1 }, > > { OPT_LEVELS_2_PLUS_SPEED_ONLY, OPT_munroll_only_small_loops, NULL, > > 1 }, > > + /* Turns off -frename-registers and -fweb which are enabled by > > + funroll-loops. */ > > + { OPT_LEVELS_ALL, OPT_frename_registers, NULL, 0 }, > > + { OPT_LEVELS_ALL, OPT_fweb, NULL, 0 }, > > /* Turn off -fschedule-insns by default. It tends to make the > > problem with not enough registers even worse. */ > > { OPT_LEVELS_ALL, OPT_fschedule_insns, NULL, 0 }, diff --git > > a/gcc/config/i386/i386-options.cc b/gcc/config/i386/i386-options.cc index > > e5c77f3a84d..bc1d36e36a8 100644 > > --- a/gcc/config/i386/i386-options.cc > > +++ b/gcc/config/i386/i386-options.cc > > @@ -1838,8 +1838,37 @@ ix86_recompute_optlev_based_flags (struct > > gcc_options *opts, void ix86_override_options_after_change (void) { > > + /* Default align_* from the processor table. */ > > ix86_default_align (&global_options); > > + > > ix86_recompute_optlev_based_flags (&global_options, &global_options_set); > > + > > + /* Disable unrolling small loops when there's explicit > > + -f{,no}unroll-loop. */ > > + if ((OPTION_SET_P (flag_unroll_loops)) > > + || (OPTION_SET_P (flag_unroll_all_loops) > > + && flag_unroll_all_loops)) > > + { > > + if (!OPTION_SET_P (ix86_unroll_only_small_loops)) > > + ix86_unroll_only_small_loops = 0; > > + /* Re-enable -frename-registers and -fweb if funroll-loops > > + enabled. */ > > + if (!OPTION_SET_P (flag_web)) > > + flag_web = flag_unroll_loops; > > + if (!OPTION_SET_P (flag_rename_registers)) > > + flag_rename_registers = flag_unroll_loops; > > + /* -fcunroll-grow-size default follws -f[no]-unroll-loops. */ > > + if (!OPTION_SET_P (flag_cunroll_grow_size)) > > + flag_cunroll_grow_size = flag_unroll_loops > > + || flag_peel_loops > > + || optimize >= 3; > > + } > > + else > > + { > > + if (!OPTION_SET_P (flag_cunroll_grow_size)) > > + flag_cunroll_grow_size = flag_peel_loops || optimize >= 3; > > + } > > + > > } > > > > /* Clear stack slot assignments remembered from previous functions. > > @@ -2351,7 +2380,7 @@ ix86_option_override_internal (bool main_args_p, > > > > set_ix86_tune_features (opts, ix86_tune, opts->x_ix86_dump_tunes); > > > > - ix86_recompute_optlev_based_flags (opts, opts_set); > > + ix86_override_options_after_change (); > > > > ix86_tune_cost = processor_cost_table[ix86_tune]; > > /* TODO: ix86_cost should be chosen at instruction or function granuality > > @@ -2382,9 +2411,6 @@ ix86_option_override_internal (bool main_args_p, > > || TARGET_64BIT_P (opts->x_ix86_isa_flags)) > > opts->x_ix86_regparm = REGPARM_MAX; > > > > - /* Default align_* from the processor table. */ > > - ix86_default_align (opts); > > - > > /* Provide default for -mbranch-cost= value. */ > > SET_OPTION_IF_UNSET (opts, opts_set, ix86_branch_cost, > > ix86_tune_cost->branch_cost); > > diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc index > > 292b32c5e99..10f8b4e91a5 100644 > > --- a/gcc/config/i386/i386.cc > > +++ b/gcc/config/i386/i386.cc > > @@ -23829,20 +23829,12 @@ ix86_loop_unroll_adjust (unsigned nunroll, > > class loop *loop) > > > > /* Unroll small size loop when unroll factor is not explicitly > > specified. */ > > - if (!(flag_unroll_loops > > - || flag_unroll_all_loops > > - || loop->unroll)) > > + if (ix86_unroll_only_small_loops && !loop->unroll) > > { > > - nunroll = 1; > > - > > - /* Any explicit -f{no-}unroll-{all-}loops turns off > > - -munroll-only-small-loops. */ > > - if (ix86_unroll_only_small_loops > > - && !OPTION_SET_P (flag_unroll_loops) > > - && loop->ninsns <= ix86_cost->small_unroll_ninsns) > > - nunroll = ix86_cost->small_unroll_factor; > > - > > - return nunroll; > > + if (loop->ninsns <= ix86_cost->small_unroll_ninsns) > > + return MIN (nunroll, ix86_cost->small_unroll_factor); > > + else > > + return 1; > > } > > > > if (!TARGET_ADJUST_UNROLL) > > diff --git a/gcc/loop-init.cc b/gcc/loop-init.cc index 9789efa1e11..f03c077cae1 > > 100644 > > --- a/gcc/loop-init.cc > > +++ b/gcc/loop-init.cc > > @@ -565,12 +565,10 @@ public: > > {} > > > > /* opt_pass methods: */ > > - bool gate (function *fun) final override > > + bool gate (function *) final override > > { > > - return (flag_unroll_loops || flag_unroll_all_loops || cfun->has_unroll > > - || (targetm.loop_unroll_adjust > > - && optimize >= 2 > > - && optimize_function_for_speed_p (fun))); > > + return (flag_unroll_loops || flag_unroll_all_loops > > + || cfun->has_unroll); > > } > > > > unsigned int execute (function *) final override; @@ -586,8 +584,7 @@ > > pass_rtl_unroll_loops::execute (function *fun) > > if (dump_file) > > df_dump (dump_file); > > > > - if (flag_unroll_loops > > - || targetm.loop_unroll_adjust) > > + if (flag_unroll_loops) > > flags |= UAP_UNROLL; > > if (flag_unroll_all_loops) > > flags |= UAP_UNROLL_ALL; > > diff --git a/gcc/testsuite/gcc.target/i386/pr86270.c > > b/gcc/testsuite/gcc.target/i386/pr86270.c > > index cbc9fbb0450..98b012caf23 100644 > > --- a/gcc/testsuite/gcc.target/i386/pr86270.c > > +++ b/gcc/testsuite/gcc.target/i386/pr86270.c > > @@ -1,5 +1,5 @@ > > /* { dg-do compile } */ > > -/* { dg-options "-O2 -mno-unroll-only-small-loops" } */ > > +/* { dg-options "-O2 -fno-unroll-loops" } */ > > > > int *a; > > long len; > > diff --git a/gcc/testsuite/gcc.target/i386/pr93002.c > > b/gcc/testsuite/gcc.target/i386/pr93002.c > > index f75a847f75d..7e2d869e17b 100644 > > --- a/gcc/testsuite/gcc.target/i386/pr93002.c > > +++ b/gcc/testsuite/gcc.target/i386/pr93002.c > > @@ -1,6 +1,6 @@ > > /* PR target/93002 */ > > /* { dg-do compile } */ > > -/* { dg-options "-O2 -mno-unroll-only-small-loops" } */ > > +/* { dg-options "-O2 -fno-unroll-loops" } */ > > /* { dg-final { scan-assembler-not "cmp\[^\n\r]*-1" } } */ > > > > volatile int sink; > > -- > > 2.18.1 >
> It's not necessarily right. unroll_factor will be set as 1 when > -fno-unroll-loops, which is exactly -fno-unroll-loops means. Not that exactly, -fno-unroll-loops previously will prevent the pass from running, and on the current trunk the pass still runs. Actually I think the implementation on trunk is a bit tricky since we use a target hook without return value to execute the pass. Also the logic !OPTION_SET_P looks quite like a workaround. IMHO this is also not good for maintenance. Hongtao Liu via Gcc-patches <gcc-patches@gcc.gnu.org> 于2022年11月21日周一 09:33写道： > > On Mon, Nov 21, 2022 at 9:01 AM Liu, Hongtao via Gcc-patches > <gcc-patches@gcc.gnu.org> wrote: > > > > > > > > > -----Original Message----- > > > From: Wang, Hongyu <hongyu.wang@intel.com> > > > Sent: Saturday, November 19, 2022 2:26 PM > > > To: gcc-patches@gcc.gnu.org > > > Cc: richard.guenther@gmail.com; ubizjak@gmail.com; Liu, Hongtao > > > <hongtao.liu@intel.com> > > > Subject: [PATCH] i386: Only enable small loop unrolling in backend [PR 107602] > > > > > > Hi, > > > > > > Followed by the discussion in pr107602, -munroll-only-small-loops Does not > > PR107692? > > > turns on/off -funroll-loops, and current check in pass_rtl_unroll_loops::gate > > > would cause -funroll-loops do not take effect. Revert the change about > It's not necessarily right. unroll_factor will be set as 1 when > -fno-unroll-loops, which is exactly -fno-unroll-loops means. > > > targetm.loop_unroll_adjust and apply the backend option change to strictly > > > follow the rule that -funroll-loops takes full control of loop unrolling, and > > > munroll-only-small-loops just change its behavior to unroll small size loops. > > > > > > Bootstrapped and regtested on x86-64-pc-linux-gnu. > > > > > > Ok for trunk? > > > > > > gcc/ChangeLog: > > > > > > PR target/107602 > > > * common/config/i386/i386-common.cc (ix86_optimization_table): > > > Enable loop unroll O2, disable -fweb and -frename-registers > > > by default. > > > * config/i386/i386-options.cc > > > (ix86_override_options_after_change): > > > Disable small loop unroll when funroll-loops enabled, reset > > > cunroll_grow_size when it is not explicitly enabled. > > > (ix86_option_override_internal): Call > > > ix86_override_options_after_change instead of calling > > > ix86_recompute_optlev_based_flags and ix86_default_align > > > separately. > > > * config/i386/i386.cc (ix86_loop_unroll_adjust): Adjust unroll > > > factor if -munroll-only-small-loops enabled. > > > * loop-init.cc (pass_rtl_unroll_loops::gate): Do not enable > > > loop unrolling for -O2-speed. > > > (pass_rtl_unroll_loops::execute): Rmove > > > targetm.loop_unroll_adjust check. > > > > > > gcc/testsuite/ChangeLog: > > > > > > PR target/107602 > > > * gcc.target/i386/pr86270.c: Add -fno-unroll-loops. > > > * gcc.target/i386/pr93002.c: Likewise. > > > --- > > > gcc/common/config/i386/i386-common.cc | 8 ++++++ > > > gcc/config/i386/i386-options.cc | 34 ++++++++++++++++++++++--- > > > gcc/config/i386/i386.cc | 18 ++++--------- > > > gcc/loop-init.cc | 11 +++----- > > > gcc/testsuite/gcc.target/i386/pr86270.c | 2 +- > > > gcc/testsuite/gcc.target/i386/pr93002.c | 2 +- > > > 6 files changed, 49 insertions(+), 26 deletions(-) > > > > > > diff --git a/gcc/common/config/i386/i386-common.cc > > > b/gcc/common/config/i386/i386-common.cc > > > index 6ce2a588adc..660a977b68b 100644 > > > --- a/gcc/common/config/i386/i386-common.cc > > > +++ b/gcc/common/config/i386/i386-common.cc > > > @@ -1808,7 +1808,15 @@ static const struct default_options > > > ix86_option_optimization_table[] = > > > /* The STC algorithm produces the smallest code at -Os, for x86. */ > > > { OPT_LEVELS_2_PLUS, OPT_freorder_blocks_algorithm_, NULL, > > > REORDER_BLOCKS_ALGORITHM_STC }, > > > + > > > + /* Turn on -funroll-loops with -munroll-only-small-loops to enable small > > > + loop unrolling at -O2. */ > > > + { OPT_LEVELS_2_PLUS_SPEED_ONLY, OPT_funroll_loops, NULL, 1 }, > > > { OPT_LEVELS_2_PLUS_SPEED_ONLY, OPT_munroll_only_small_loops, NULL, > > > 1 }, > > > + /* Turns off -frename-registers and -fweb which are enabled by > > > + funroll-loops. */ > > > + { OPT_LEVELS_ALL, OPT_frename_registers, NULL, 0 }, > > > + { OPT_LEVELS_ALL, OPT_fweb, NULL, 0 }, > > > /* Turn off -fschedule-insns by default. It tends to make the > > > problem with not enough registers even worse. */ > > > { OPT_LEVELS_ALL, OPT_fschedule_insns, NULL, 0 }, diff --git > > > a/gcc/config/i386/i386-options.cc b/gcc/config/i386/i386-options.cc index > > > e5c77f3a84d..bc1d36e36a8 100644 > > > --- a/gcc/config/i386/i386-options.cc > > > +++ b/gcc/config/i386/i386-options.cc > > > @@ -1838,8 +1838,37 @@ ix86_recompute_optlev_based_flags (struct > > > gcc_options *opts, void ix86_override_options_after_change (void) { > > > + /* Default align_* from the processor table. */ > > > ix86_default_align (&global_options); > > > + > > > ix86_recompute_optlev_based_flags (&global_options, &global_options_set); > > > + > > > + /* Disable unrolling small loops when there's explicit > > > + -f{,no}unroll-loop. */ > > > + if ((OPTION_SET_P (flag_unroll_loops)) > > > + || (OPTION_SET_P (flag_unroll_all_loops) > > > + && flag_unroll_all_loops)) > > > + { > > > + if (!OPTION_SET_P (ix86_unroll_only_small_loops)) > > > + ix86_unroll_only_small_loops = 0; > > > + /* Re-enable -frename-registers and -fweb if funroll-loops > > > + enabled. */ > > > + if (!OPTION_SET_P (flag_web)) > > > + flag_web = flag_unroll_loops; > > > + if (!OPTION_SET_P (flag_rename_registers)) > > > + flag_rename_registers = flag_unroll_loops; > > > + /* -fcunroll-grow-size default follws -f[no]-unroll-loops. */ > > > + if (!OPTION_SET_P (flag_cunroll_grow_size)) > > > + flag_cunroll_grow_size = flag_unroll_loops > > > + || flag_peel_loops > > > + || optimize >= 3; > > > + } > > > + else > > > + { > > > + if (!OPTION_SET_P (flag_cunroll_grow_size)) > > > + flag_cunroll_grow_size = flag_peel_loops || optimize >= 3; > > > + } > > > + > > > } > > > > > > /* Clear stack slot assignments remembered from previous functions. > > > @@ -2351,7 +2380,7 @@ ix86_option_override_internal (bool main_args_p, > > > > > > set_ix86_tune_features (opts, ix86_tune, opts->x_ix86_dump_tunes); > > > > > > - ix86_recompute_optlev_based_flags (opts, opts_set); > > > + ix86_override_options_after_change (); > > > > > > ix86_tune_cost = processor_cost_table[ix86_tune]; > > > /* TODO: ix86_cost should be chosen at instruction or function granuality > > > @@ -2382,9 +2411,6 @@ ix86_option_override_internal (bool main_args_p, > > > || TARGET_64BIT_P (opts->x_ix86_isa_flags)) > > > opts->x_ix86_regparm = REGPARM_MAX; > > > > > > - /* Default align_* from the processor table. */ > > > - ix86_default_align (opts); > > > - > > > /* Provide default for -mbranch-cost= value. */ > > > SET_OPTION_IF_UNSET (opts, opts_set, ix86_branch_cost, > > > ix86_tune_cost->branch_cost); > > > diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc index > > > 292b32c5e99..10f8b4e91a5 100644 > > > --- a/gcc/config/i386/i386.cc > > > +++ b/gcc/config/i386/i386.cc > > > @@ -23829,20 +23829,12 @@ ix86_loop_unroll_adjust (unsigned nunroll, > > > class loop *loop) > > > > > > /* Unroll small size loop when unroll factor is not explicitly > > > specified. */ > > > - if (!(flag_unroll_loops > > > - || flag_unroll_all_loops > > > - || loop->unroll)) > > > + if (ix86_unroll_only_small_loops && !loop->unroll) > > > { > > > - nunroll = 1; > > > - > > > - /* Any explicit -f{no-}unroll-{all-}loops turns off > > > - -munroll-only-small-loops. */ > > > - if (ix86_unroll_only_small_loops > > > - && !OPTION_SET_P (flag_unroll_loops) > > > - && loop->ninsns <= ix86_cost->small_unroll_ninsns) > > > - nunroll = ix86_cost->small_unroll_factor; > > > - > > > - return nunroll; > > > + if (loop->ninsns <= ix86_cost->small_unroll_ninsns) > > > + return MIN (nunroll, ix86_cost->small_unroll_factor); > > > + else > > > + return 1; > > > } > > > > > > if (!TARGET_ADJUST_UNROLL) > > > diff --git a/gcc/loop-init.cc b/gcc/loop-init.cc index 9789efa1e11..f03c077cae1 > > > 100644 > > > --- a/gcc/loop-init.cc > > > +++ b/gcc/loop-init.cc > > > @@ -565,12 +565,10 @@ public: > > > {} > > > > > > /* opt_pass methods: */ > > > - bool gate (function *fun) final override > > > + bool gate (function *) final override > > > { > > > - return (flag_unroll_loops || flag_unroll_all_loops || cfun->has_unroll > > > - || (targetm.loop_unroll_adjust > > > - && optimize >= 2 > > > - && optimize_function_for_speed_p (fun))); > > > + return (flag_unroll_loops || flag_unroll_all_loops > > > + || cfun->has_unroll); > > > } > > > > > > unsigned int execute (function *) final override; @@ -586,8 +584,7 @@ > > > pass_rtl_unroll_loops::execute (function *fun) > > > if (dump_file) > > > df_dump (dump_file); > > > > > > - if (flag_unroll_loops > > > - || targetm.loop_unroll_adjust) > > > + if (flag_unroll_loops) > > > flags |= UAP_UNROLL; > > > if (flag_unroll_all_loops) > > > flags |= UAP_UNROLL_ALL; > > > diff --git a/gcc/testsuite/gcc.target/i386/pr86270.c > > > b/gcc/testsuite/gcc.target/i386/pr86270.c > > > index cbc9fbb0450..98b012caf23 100644 > > > --- a/gcc/testsuite/gcc.target/i386/pr86270.c > > > +++ b/gcc/testsuite/gcc.target/i386/pr86270.c > > > @@ -1,5 +1,5 @@ > > > /* { dg-do compile } */ > > > -/* { dg-options "-O2 -mno-unroll-only-small-loops" } */ > > > +/* { dg-options "-O2 -fno-unroll-loops" } */ > > > > > > int *a; > > > long len; > > > diff --git a/gcc/testsuite/gcc.target/i386/pr93002.c > > > b/gcc/testsuite/gcc.target/i386/pr93002.c > > > index f75a847f75d..7e2d869e17b 100644 > > > --- a/gcc/testsuite/gcc.target/i386/pr93002.c > > > +++ b/gcc/testsuite/gcc.target/i386/pr93002.c > > > @@ -1,6 +1,6 @@ > > > /* PR target/93002 */ > > > /* { dg-do compile } */ > > > -/* { dg-options "-O2 -mno-unroll-only-small-loops" } */ > > > +/* { dg-options "-O2 -fno-unroll-loops" } */ > > > /* { dg-final { scan-assembler-not "cmp\[^\n\r]*-1" } } */ > > > > > > volatile int sink; > > > -- > > > 2.18.1 > > > > > -- > BR, > Hongtao
On 11/18/22 23:25, Hongyu Wang via Gcc-patches wrote: > Hi, > > Followed by the discussion in pr107602, -munroll-only-small-loops > Does not turns on/off -funroll-loops, and current check in > pass_rtl_unroll_loops::gate would cause -funroll-loops do not take > effect. Revert the change about targetm.loop_unroll_adjust and apply > the backend option change to strictly follow the rule that > -funroll-loops takes full control of loop unrolling, and > munroll-only-small-loops just change its behavior to unroll small size > loops. > > Bootstrapped and regtested on x86-64-pc-linux-gnu. > > Ok for trunk? > > gcc/ChangeLog: > > PR target/107602 > * common/config/i386/i386-common.cc (ix86_optimization_table): > Enable loop unroll O2, disable -fweb and -frename-registers > by default. > * config/i386/i386-options.cc > (ix86_override_options_after_change): > Disable small loop unroll when funroll-loops enabled, reset > cunroll_grow_size when it is not explicitly enabled. > (ix86_option_override_internal): Call > ix86_override_options_after_change instead of calling > ix86_recompute_optlev_based_flags and ix86_default_align > separately. > * config/i386/i386.cc (ix86_loop_unroll_adjust): Adjust unroll > factor if -munroll-only-small-loops enabled. > * loop-init.cc (pass_rtl_unroll_loops::gate): Do not enable > loop unrolling for -O2-speed. > (pass_rtl_unroll_loops::execute): Rmove > targetm.loop_unroll_adjust check. The reversion of the loop-init.cc changes is fine. The x86 maintainers will need to chime in on the rest. Consider installing the loop-init.cc reversion immediately as the current state has regressed s390 and potentially other targets. jeff
On Tue, Nov 22, 2022 at 1:41 AM Jeff Law via Gcc-patches <gcc-patches@gcc.gnu.org> wrote: > > > On 11/18/22 23:25, Hongyu Wang via Gcc-patches wrote: > > Hi, > > > > Followed by the discussion in pr107602, -munroll-only-small-loops > > Does not turns on/off -funroll-loops, and current check in > > pass_rtl_unroll_loops::gate would cause -funroll-loops do not take > > effect. Revert the change about targetm.loop_unroll_adjust and apply > > the backend option change to strictly follow the rule that > > -funroll-loops takes full control of loop unrolling, and > > munroll-only-small-loops just change its behavior to unroll small size > > loops. > > > > Bootstrapped and regtested on x86-64-pc-linux-gnu. > > > > Ok for trunk? > > > > gcc/ChangeLog: > > > > PR target/107602 > > * common/config/i386/i386-common.cc (ix86_optimization_table): > > Enable loop unroll O2, disable -fweb and -frename-registers > > by default. > > * config/i386/i386-options.cc > > (ix86_override_options_after_change): > > Disable small loop unroll when funroll-loops enabled, reset > > cunroll_grow_size when it is not explicitly enabled. > > (ix86_option_override_internal): Call > > ix86_override_options_after_change instead of calling > > ix86_recompute_optlev_based_flags and ix86_default_align > > separately. > > * config/i386/i386.cc (ix86_loop_unroll_adjust): Adjust unroll > > factor if -munroll-only-small-loops enabled. > > * loop-init.cc (pass_rtl_unroll_loops::gate): Do not enable > > loop unrolling for -O2-speed. > > (pass_rtl_unroll_loops::execute): Rmove > > targetm.loop_unroll_adjust check. > The reversion of the loop-init.cc changes is fine. The x86 maintainers > will need to chime in on the rest. Consider installing the loop-init.cc > reversion immediately as the current state has regressed s390 and > potentially other targets. x86 part is ok. > > > jeff >
Hi Jeff, > The reversion of the loop-init.cc changes is fine. The x86 maintainers > will need to chime in on the rest. Consider installing the loop-init.cc > reversion immediately as the current state has regressed s390 and > potentially other targets. I've posted a patch in https://gcc.gnu.org/pipermail/gcc-patches/2022-November/606478.html to change the rs6000 target and there is a discussion ongoing. If we draw a conclusion that we only want to make changes in the backend, I will install this one.
diff --git a/gcc/common/config/i386/i386-common.cc b/gcc/common/config/i386/i386-common.cc index 6ce2a588adc..660a977b68b 100644 --- a/gcc/common/config/i386/i386-common.cc +++ b/gcc/common/config/i386/i386-common.cc @@ -1808,7 +1808,15 @@ static const struct default_options ix86_option_optimization_table[] = /* The STC algorithm produces the smallest code at -Os, for x86. */ { OPT_LEVELS_2_PLUS, OPT_freorder_blocks_algorithm_, NULL, REORDER_BLOCKS_ALGORITHM_STC }, + + /* Turn on -funroll-loops with -munroll-only-small-loops to enable small + loop unrolling at -O2. */ + { OPT_LEVELS_2_PLUS_SPEED_ONLY, OPT_funroll_loops, NULL, 1 }, { OPT_LEVELS_2_PLUS_SPEED_ONLY, OPT_munroll_only_small_loops, NULL, 1 }, + /* Turns off -frename-registers and -fweb which are enabled by + funroll-loops. */ + { OPT_LEVELS_ALL, OPT_frename_registers, NULL, 0 }, + { OPT_LEVELS_ALL, OPT_fweb, NULL, 0 }, /* Turn off -fschedule-insns by default. It tends to make the problem with not enough registers even worse. */ { OPT_LEVELS_ALL, OPT_fschedule_insns, NULL, 0 }, diff --git a/gcc/config/i386/i386-options.cc b/gcc/config/i386/i386-options.cc index e5c77f3a84d..bc1d36e36a8 100644 --- a/gcc/config/i386/i386-options.cc +++ b/gcc/config/i386/i386-options.cc @@ -1838,8 +1838,37 @@ ix86_recompute_optlev_based_flags (struct gcc_options *opts, void ix86_override_options_after_change (void) { + /* Default align_* from the processor table. */ ix86_default_align (&global_options); + ix86_recompute_optlev_based_flags (&global_options, &global_options_set); + + /* Disable unrolling small loops when there's explicit + -f{,no}unroll-loop. */ + if ((OPTION_SET_P (flag_unroll_loops)) + || (OPTION_SET_P (flag_unroll_all_loops) + && flag_unroll_all_loops)) + { + if (!OPTION_SET_P (ix86_unroll_only_small_loops)) + ix86_unroll_only_small_loops = 0; + /* Re-enable -frename-registers and -fweb if funroll-loops + enabled. */ + if (!OPTION_SET_P (flag_web)) + flag_web = flag_unroll_loops; + if (!OPTION_SET_P (flag_rename_registers)) + flag_rename_registers = flag_unroll_loops; + /* -fcunroll-grow-size default follws -f[no]-unroll-loops. */ + if (!OPTION_SET_P (flag_cunroll_grow_size)) + flag_cunroll_grow_size = flag_unroll_loops + || flag_peel_loops + || optimize >= 3; + } + else + { + if (!OPTION_SET_P (flag_cunroll_grow_size)) + flag_cunroll_grow_size = flag_peel_loops || optimize >= 3; + } + } /* Clear stack slot assignments remembered from previous functions. @@ -2351,7 +2380,7 @@ ix86_option_override_internal (bool main_args_p, set_ix86_tune_features (opts, ix86_tune, opts->x_ix86_dump_tunes); - ix86_recompute_optlev_based_flags (opts, opts_set); + ix86_override_options_after_change (); ix86_tune_cost = processor_cost_table[ix86_tune]; /* TODO: ix86_cost should be chosen at instruction or function granuality @@ -2382,9 +2411,6 @@ ix86_option_override_internal (bool main_args_p, || TARGET_64BIT_P (opts->x_ix86_isa_flags)) opts->x_ix86_regparm = REGPARM_MAX; - /* Default align_* from the processor table. */ - ix86_default_align (opts); - /* Provide default for -mbranch-cost= value. */ SET_OPTION_IF_UNSET (opts, opts_set, ix86_branch_cost, ix86_tune_cost->branch_cost); diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc index 292b32c5e99..10f8b4e91a5 100644 --- a/gcc/config/i386/i386.cc +++ b/gcc/config/i386/i386.cc @@ -23829,20 +23829,12 @@ ix86_loop_unroll_adjust (unsigned nunroll, class loop *loop) /* Unroll small size loop when unroll factor is not explicitly specified. */ - if (!(flag_unroll_loops - || flag_unroll_all_loops - || loop->unroll)) + if (ix86_unroll_only_small_loops && !loop->unroll) { - nunroll = 1; - - /* Any explicit -f{no-}unroll-{all-}loops turns off - -munroll-only-small-loops. */ - if (ix86_unroll_only_small_loops - && !OPTION_SET_P (flag_unroll_loops) - && loop->ninsns <= ix86_cost->small_unroll_ninsns) - nunroll = ix86_cost->small_unroll_factor; - - return nunroll; + if (loop->ninsns <= ix86_cost->small_unroll_ninsns) + return MIN (nunroll, ix86_cost->small_unroll_factor); + else + return 1; } if (!TARGET_ADJUST_UNROLL) diff --git a/gcc/loop-init.cc b/gcc/loop-init.cc index 9789efa1e11..f03c077cae1 100644 --- a/gcc/loop-init.cc +++ b/gcc/loop-init.cc @@ -565,12 +565,10 @@ public: {} /* opt_pass methods: */ - bool gate (function *fun) final override + bool gate (function *) final override { - return (flag_unroll_loops || flag_unroll_all_loops || cfun->has_unroll - || (targetm.loop_unroll_adjust - && optimize >= 2 - && optimize_function_for_speed_p (fun))); + return (flag_unroll_loops || flag_unroll_all_loops + || cfun->has_unroll); } unsigned int execute (function *) final override; @@ -586,8 +584,7 @@ pass_rtl_unroll_loops::execute (function *fun) if (dump_file) df_dump (dump_file); - if (flag_unroll_loops - || targetm.loop_unroll_adjust) + if (flag_unroll_loops) flags |= UAP_UNROLL; if (flag_unroll_all_loops) flags |= UAP_UNROLL_ALL; diff --git a/gcc/testsuite/gcc.target/i386/pr86270.c b/gcc/testsuite/gcc.target/i386/pr86270.c index cbc9fbb0450..98b012caf23 100644 --- a/gcc/testsuite/gcc.target/i386/pr86270.c +++ b/gcc/testsuite/gcc.target/i386/pr86270.c @@ -1,5 +1,5 @@ /* { dg-do compile } */ -/* { dg-options "-O2 -mno-unroll-only-small-loops" } */ +/* { dg-options "-O2 -fno-unroll-loops" } */ int *a; long len; diff --git a/gcc/testsuite/gcc.target/i386/pr93002.c b/gcc/testsuite/gcc.target/i386/pr93002.c index f75a847f75d..7e2d869e17b 100644 --- a/gcc/testsuite/gcc.target/i386/pr93002.c +++ b/gcc/testsuite/gcc.target/i386/pr93002.c @@ -1,6 +1,6 @@ /* PR target/93002 */ /* { dg-do compile } */ -/* { dg-options "-O2 -mno-unroll-only-small-loops" } */ +/* { dg-options "-O2 -fno-unroll-loops" } */ /* { dg-final { scan-assembler-not "cmp\[^\n\r]*-1" } } */ volatile int sink;