| Message ID | CAAgBjMmzvQG5GLsWsX86cP2c=ZcRJXU+iRzho0RcNy_ej+WVvw@mail.gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
On 10 June 2016 at 01:53, Jan Hubicka <hubicka@ucw.cz> wrote: >> On 8 June 2016 at 20:38, Jan Hubicka <hubicka@ucw.cz> wrote: >> >> I think it would be nice to work towards transitioning >> >> flag_section_anchors to a flag on varpool nodes, thereby removing >> >> the Optimization flag from common.opt:fsection-anchors >> >> >> >> That would simplify the walk over varpool candidates. >> > >> > Makes sense to me, too. There are more candidates for sutff that should be >> > variable specific in common.opt (such as variable alignment, -fdata-sctions, >> > -fmerge-constants) and targets. We may try to do it in an easy to extend way >> > so incrementally we can get rid of those global flags, too. >> In this version I removed Optimization from fsection-anchors entry in >> common.opt, >> and gated the increase_alignment pass on flag_section_anchors != 0. >> Cross tested on arm*-*-*, aarch64*-*-*. >> Does it look OK ? > > If you go this way you will need to do something sane for LTO. Here one can compile > some object files with -fsection-anchors and other without and link with random setting > (because in traditional compilation linktime flags does not matter). > > For global flags we have magic in merge_and_complain that determines flags to pass > to the LTO compiler. > It is not very robust though. >> > >> > One thing that needs to be done for LTO is sane merging, I guess in this case >> > it is clear that the variable should be anchored when its previaling definition >> > is. >> Um could we determine during WPA if symbol is a section anchor for merging ? >> Seems to me SYMBOL_REF_ANCHOR_P is defined only on DECL_RTL and not at >> tree level. >> Do we have DECL_RTL info available during WPA ? > > We don't have anchros computed, but we can decide whether we want to potentially > anchor the variable if we can. > > I would say all you need is to have section_anchor flag in varpool node itself > which controls RTL production. At varpool_finalize_decl you will set it > according to flag_varpool and stream it to LTO objects. At WPA when doing > linking, the section_anchor flag of the previaling decl wins.. Thanks for the suggestions. IIUC, we want to add new section_anchor flag to varpool_node class and set it in varpool_node::finalize_decl and stream it to LTO byte-code, and then during WPA set section_anchor_flag during symbol merging if it is set for prevailing decl. In the increase_alignment_pass if a vnode has section_anchor flag set, we will walk all functions that reference it to check if they have -ftree-loop-vectorize set. Is that correct ? Could you please elaborate a bit more on "at varpool_finalize_decl you will set section_anchor flag according to flag_varpool" ? flag_varpool doesn't appear to be defined. Thanks, Prathamesh > > Honza >> >> Thanks, >> Prathamesh >> > >> > Honza >> >> >> >> Richard. >> >> >> >> > Thanks, >> >> > Prathamesh >> >> > > >> >> > > Honza >> >> > >> >> >> > >> Richard. >> >> > >> >> > >> >> >> >> -- >> >> Richard Biener <rguenther@suse.de> >> >> SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nuernberg) > >> diff --git a/gcc/common.opt b/gcc/common.opt >> index f0d7196..f93f26c 100644 >> --- a/gcc/common.opt >> +++ b/gcc/common.opt >> @@ -2133,7 +2133,7 @@ Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization >> Enable the dependent count heuristic in the scheduler. >> >> fsection-anchors >> -Common Report Var(flag_section_anchors) Optimization >> +Common Report Var(flag_section_anchors) >> Access data in the same section from shared anchor points. >> >> fsee >> diff --git a/gcc/passes.def b/gcc/passes.def >> index 3647e90..3a8063c 100644 >> --- a/gcc/passes.def >> +++ b/gcc/passes.def >> @@ -138,12 +138,12 @@ along with GCC; see the file COPYING3. If not see >> PUSH_INSERT_PASSES_WITHIN (pass_ipa_tree_profile) >> NEXT_PASS (pass_feedback_split_functions); >> POP_INSERT_PASSES () >> - NEXT_PASS (pass_ipa_increase_alignment); >> NEXT_PASS (pass_ipa_tm); >> NEXT_PASS (pass_ipa_lower_emutls); >> TERMINATE_PASS_LIST (all_small_ipa_passes) >> >> INSERT_PASSES_AFTER (all_regular_ipa_passes) >> + NEXT_PASS (pass_ipa_increase_alignment); >> NEXT_PASS (pass_ipa_whole_program_visibility); >> NEXT_PASS (pass_ipa_profile); >> NEXT_PASS (pass_ipa_icf); >> diff --git a/gcc/testsuite/gcc.dg/vect/aligned-section-anchors-vect-73.c b/gcc/testsuite/gcc.dg/vect/aligned-section-anchors-vect-73.c >> new file mode 100644 >> index 0000000..74eaed8 >> --- /dev/null >> +++ b/gcc/testsuite/gcc.dg/vect/aligned-section-anchors-vect-73.c >> @@ -0,0 +1,25 @@ >> +/* { dg-do compile } */ >> +/* { dg-require-effective-target section_anchors } */ >> +/* { dg-require-effective-target vect_int } */ >> + >> +#define N 32 >> + >> +/* Clone of section-anchors-vect-70.c with foo() having -fno-tree-loop-vectorize. */ >> + >> +static struct A { >> + int p1, p2; >> + int e[N]; >> +} a, b, c; >> + >> +__attribute__((optimize("-fno-tree-loop-vectorize"))) >> +int foo(void) >> +{ >> + for (int i = 0; i < N; i++) >> + a.e[i] = b.e[i] + c.e[i]; >> + >> + return a.e[0]; >> +} >> + >> +/* { dg-final { scan-ipa-dump-times "Increasing alignment of decl" 0 "increase_alignment" { target aarch64*-*-* } } } */ >> +/* { dg-final { scan-ipa-dump-times "Increasing alignment of decl" 0 "increase_alignment" { target powerpc64*-*-* } } } */ >> +/* { dg-final { scan-ipa-dump-times "Increasing alignment of decl" 0 "increase_alignment" { target arm*-*-* } } } */ >> diff --git a/gcc/tree-pass.h b/gcc/tree-pass.h >> index 36299a6..d36aa1d 100644 >> --- a/gcc/tree-pass.h >> +++ b/gcc/tree-pass.h >> @@ -483,7 +483,7 @@ extern simple_ipa_opt_pass *make_pass_local_optimization_passes (gcc::context *c >> >> extern ipa_opt_pass_d *make_pass_ipa_whole_program_visibility (gcc::context >> *ctxt); >> -extern simple_ipa_opt_pass *make_pass_ipa_increase_alignment (gcc::context >> +extern ipa_opt_pass_d *make_pass_ipa_increase_alignment (gcc::context >> *ctxt); >> extern ipa_opt_pass_d *make_pass_ipa_inline (gcc::context *ctxt); >> extern simple_ipa_opt_pass *make_pass_ipa_free_lang_data (gcc::context *ctxt); >> diff --git a/gcc/tree-vectorizer.c b/gcc/tree-vectorizer.c >> index 2669813..d34e560 100644 >> --- a/gcc/tree-vectorizer.c >> +++ b/gcc/tree-vectorizer.c >> @@ -899,6 +899,34 @@ get_vec_alignment_for_type (tree type) >> return (alignment > TYPE_ALIGN (type)) ? alignment : 0; >> } >> >> +/* Return true if alignment should be increased for this vnode. >> + This is done if every function that references/referring to vnode >> + has flag_tree_loop_vectorize and flag_section_anchors set. */ >> + >> +static bool >> +increase_alignment_p (varpool_node *vnode) >> +{ >> + ipa_ref *ref; >> + >> + for (int i = 0; vnode->iterate_reference (i, ref); i++) >> + if (cgraph_node *cnode = dyn_cast<cgraph_node *> (ref->referred)) >> + { >> + struct cl_optimization *opts = opts_for_fn (cnode->decl); >> + if (!opts->x_flag_tree_loop_vectorize) >> + return false; >> + } >> + >> + for (int i = 0; vnode->iterate_referring (i, ref); i++) >> + if (cgraph_node *cnode = dyn_cast<cgraph_node *> (ref->referring)) >> + { >> + struct cl_optimization *opts = opts_for_fn (cnode->decl); >> + if (!opts->x_flag_tree_loop_vectorize) >> + return false; >> + } >> + >> + return true; >> +} >> + >> /* Entry point to increase_alignment pass. */ >> static unsigned int >> increase_alignment (void) >> @@ -916,7 +944,8 @@ increase_alignment (void) >> >> if ((decl_in_symtab_p (decl) >> && !symtab_node::get (decl)->can_increase_alignment_p ()) >> - || DECL_USER_ALIGN (decl) || DECL_ARTIFICIAL (decl)) >> + || DECL_USER_ALIGN (decl) || DECL_ARTIFICIAL (decl) >> + || !increase_alignment_p (vnode)) >> continue; >> >> alignment = get_vec_alignment_for_type (TREE_TYPE (decl)); >> @@ -938,7 +967,7 @@ namespace { >> >> const pass_data pass_data_ipa_increase_alignment = >> { >> - SIMPLE_IPA_PASS, /* type */ >> + IPA_PASS, /* type */ >> "increase_alignment", /* name */ >> OPTGROUP_LOOP | OPTGROUP_VEC, /* optinfo_flags */ >> TV_IPA_OPT, /* tv_id */ >> @@ -949,17 +978,26 @@ const pass_data pass_data_ipa_increase_alignment = >> 0, /* todo_flags_finish */ >> }; >> >> -class pass_ipa_increase_alignment : public simple_ipa_opt_pass >> +class pass_ipa_increase_alignment : public ipa_opt_pass_d >> { >> public: >> pass_ipa_increase_alignment (gcc::context *ctxt) >> - : simple_ipa_opt_pass (pass_data_ipa_increase_alignment, ctxt) >> + : ipa_opt_pass_d (pass_data_ipa_increase_alignment, ctxt, >> + NULL, /* generate_summary */ >> + NULL, /* write summary */ >> + NULL, /* read summary */ >> + NULL, /* write optimization summary */ >> + NULL, /* read optimization summary */ >> + NULL, /* stmt fixup */ >> + 0, /* function_transform_todo_flags_start */ >> + NULL, /* transform function */ >> + NULL )/* variable transform */ >> {} >> >> /* opt_pass methods: */ >> virtual bool gate (function *) >> { >> - return flag_section_anchors && flag_tree_loop_vectorize; >> + return flag_section_anchors != 0; >> } >> >> virtual unsigned int execute (function *) { return increase_alignment (); } >> @@ -968,7 +1006,7 @@ public: >> >> } // anon namespace >> >> -simple_ipa_opt_pass * >> +ipa_opt_pass_d * >> make_pass_ipa_increase_alignment (gcc::context *ctxt) >> { >> return new pass_ipa_increase_alignment (ctxt); >
diff --git a/gcc/common.opt b/gcc/common.opt index f0d7196..f93f26c 100644 --- a/gcc/common.opt +++ b/gcc/common.opt @@ -2133,7 +2133,7 @@ Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization Enable the dependent count heuristic in the scheduler. fsection-anchors -Common Report Var(flag_section_anchors) Optimization +Common Report Var(flag_section_anchors) Access data in the same section from shared anchor points. fsee diff --git a/gcc/passes.def b/gcc/passes.def index 3647e90..3a8063c 100644 --- a/gcc/passes.def +++ b/gcc/passes.def @@ -138,12 +138,12 @@ along with GCC; see the file COPYING3. If not see PUSH_INSERT_PASSES_WITHIN (pass_ipa_tree_profile) NEXT_PASS (pass_feedback_split_functions); POP_INSERT_PASSES () - NEXT_PASS (pass_ipa_increase_alignment); NEXT_PASS (pass_ipa_tm); NEXT_PASS (pass_ipa_lower_emutls); TERMINATE_PASS_LIST (all_small_ipa_passes) INSERT_PASSES_AFTER (all_regular_ipa_passes) + NEXT_PASS (pass_ipa_increase_alignment); NEXT_PASS (pass_ipa_whole_program_visibility); NEXT_PASS (pass_ipa_profile); NEXT_PASS (pass_ipa_icf); diff --git a/gcc/testsuite/gcc.dg/vect/aligned-section-anchors-vect-73.c b/gcc/testsuite/gcc.dg/vect/aligned-section-anchors-vect-73.c new file mode 100644 index 0000000..74eaed8 --- /dev/null +++ b/gcc/testsuite/gcc.dg/vect/aligned-section-anchors-vect-73.c @@ -0,0 +1,25 @@ +/* { dg-do compile } */ +/* { dg-require-effective-target section_anchors } */ +/* { dg-require-effective-target vect_int } */ + +#define N 32 + +/* Clone of section-anchors-vect-70.c with foo() having -fno-tree-loop-vectorize. */ + +static struct A { + int p1, p2; + int e[N]; +} a, b, c; + +__attribute__((optimize("-fno-tree-loop-vectorize"))) +int foo(void) +{ + for (int i = 0; i < N; i++) + a.e[i] = b.e[i] + c.e[i]; + + return a.e[0]; +} + +/* { dg-final { scan-ipa-dump-times "Increasing alignment of decl" 0 "increase_alignment" { target aarch64*-*-* } } } */ +/* { dg-final { scan-ipa-dump-times "Increasing alignment of decl" 0 "increase_alignment" { target powerpc64*-*-* } } } */ +/* { dg-final { scan-ipa-dump-times "Increasing alignment of decl" 0 "increase_alignment" { target arm*-*-* } } } */ diff --git a/gcc/tree-pass.h b/gcc/tree-pass.h index 36299a6..d36aa1d 100644 --- a/gcc/tree-pass.h +++ b/gcc/tree-pass.h @@ -483,7 +483,7 @@ extern simple_ipa_opt_pass *make_pass_local_optimization_passes (gcc::context *c extern ipa_opt_pass_d *make_pass_ipa_whole_program_visibility (gcc::context *ctxt); -extern simple_ipa_opt_pass *make_pass_ipa_increase_alignment (gcc::context +extern ipa_opt_pass_d *make_pass_ipa_increase_alignment (gcc::context *ctxt); extern ipa_opt_pass_d *make_pass_ipa_inline (gcc::context *ctxt); extern simple_ipa_opt_pass *make_pass_ipa_free_lang_data (gcc::context *ctxt); diff --git a/gcc/tree-vectorizer.c b/gcc/tree-vectorizer.c index 2669813..d34e560 100644 --- a/gcc/tree-vectorizer.c +++ b/gcc/tree-vectorizer.c @@ -899,6 +899,34 @@ get_vec_alignment_for_type (tree type) return (alignment > TYPE_ALIGN (type)) ? alignment : 0; } +/* Return true if alignment should be increased for this vnode. + This is done if every function that references/referring to vnode + has flag_tree_loop_vectorize and flag_section_anchors set. */ + +static bool +increase_alignment_p (varpool_node *vnode) +{ + ipa_ref *ref; + + for (int i = 0; vnode->iterate_reference (i, ref); i++) + if (cgraph_node *cnode = dyn_cast<cgraph_node *> (ref->referred)) + { + struct cl_optimization *opts = opts_for_fn (cnode->decl); + if (!opts->x_flag_tree_loop_vectorize) + return false; + } + + for (int i = 0; vnode->iterate_referring (i, ref); i++) + if (cgraph_node *cnode = dyn_cast<cgraph_node *> (ref->referring)) + { + struct cl_optimization *opts = opts_for_fn (cnode->decl); + if (!opts->x_flag_tree_loop_vectorize) + return false; + } + + return true; +} + /* Entry point to increase_alignment pass. */ static unsigned int increase_alignment (void) @@ -916,7 +944,8 @@ increase_alignment (void) if ((decl_in_symtab_p (decl) && !symtab_node::get (decl)->can_increase_alignment_p ()) - || DECL_USER_ALIGN (decl) || DECL_ARTIFICIAL (decl)) + || DECL_USER_ALIGN (decl) || DECL_ARTIFICIAL (decl) + || !increase_alignment_p (vnode)) continue; alignment = get_vec_alignment_for_type (TREE_TYPE (decl)); @@ -938,7 +967,7 @@ namespace { const pass_data pass_data_ipa_increase_alignment = { - SIMPLE_IPA_PASS, /* type */ + IPA_PASS, /* type */ "increase_alignment", /* name */ OPTGROUP_LOOP | OPTGROUP_VEC, /* optinfo_flags */ TV_IPA_OPT, /* tv_id */ @@ -949,17 +978,26 @@ const pass_data pass_data_ipa_increase_alignment = 0, /* todo_flags_finish */ }; -class pass_ipa_increase_alignment : public simple_ipa_opt_pass +class pass_ipa_increase_alignment : public ipa_opt_pass_d { public: pass_ipa_increase_alignment (gcc::context *ctxt) - : simple_ipa_opt_pass (pass_data_ipa_increase_alignment, ctxt) + : ipa_opt_pass_d (pass_data_ipa_increase_alignment, ctxt, + NULL, /* generate_summary */ + NULL, /* write summary */ + NULL, /* read summary */ + NULL, /* write optimization summary */ + NULL, /* read optimization summary */ + NULL, /* stmt fixup */ + 0, /* function_transform_todo_flags_start */ + NULL, /* transform function */ + NULL )/* variable transform */ {} /* opt_pass methods: */ virtual bool gate (function *) { - return flag_section_anchors && flag_tree_loop_vectorize; + return flag_section_anchors != 0; } virtual unsigned int execute (function *) { return increase_alignment (); } @@ -968,7 +1006,7 @@ public: } // anon namespace -simple_ipa_opt_pass * +ipa_opt_pass_d * make_pass_ipa_increase_alignment (gcc::context *ctxt) { return new pass_ipa_increase_alignment (ctxt);