From 8b583a0651c326c12cd2a3d6a4cfba7bf6b68963 Mon Sep 17 00:00:00 2001 From: Jan Hubicka Date: Sat, 24 Oct 2009 15:32:12 +0200 Subject: [PATCH] ipa-reference.c (check_call): Noreturn notrhow calls do not write to memory. * ipa-reference.c (check_call): Noreturn notrhow calls do not write to memory. (analyze_function): When analyzing noreturn nothrow call, do not compute written stats; free bitmaps of vars early if possible. (generate_summary): Only update bitmaps if computed. (propagate): Only dump bitmaps if computed. (ipa_reference_read_summary): Fix pasto. From-SVN: r153529 --- gcc/ChangeLog | 10 ++++ gcc/ipa-reference.c | 122 ++++++++++++++++++++++++++++---------------- 2 files changed, 89 insertions(+), 43 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 933b664d4b0..0a42a8aa22b 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,13 @@ +2009-10-24 Jan Hubicka + + * ipa-reference.c (check_call): Noreturn notrhow calls do not write + to memory. + (analyze_function): When analyzing noreturn nothrow call, do not compute + written stats; free bitmaps of vars early if possible. + (generate_summary): Only update bitmaps if computed. + (propagate): Only dump bitmaps if computed. + (ipa_reference_read_summary): Fix pasto. + 2009-10-24 Eric Botcazou * tree-ssa-alias.c (nonaliasing_component_refs_p): Rename into... diff --git a/gcc/ipa-reference.c b/gcc/ipa-reference.c index f0e8aa0aaed..8610f13311f 100644 --- a/gcc/ipa-reference.c +++ b/gcc/ipa-reference.c @@ -427,7 +427,11 @@ check_call (ipa_reference_local_vars_info_t local, gimple stmt) else { local->calls_read_all = true; - local->calls_write_all = true; + /* When function does not reutrn, it is safe to ignore anythign it writes + to, because the effect will never happen. */ + if ((flags & (ECF_NOTHROW | ECF_NORETURN)) + != (ECF_NOTHROW | ECF_NORETURN)) + local->calls_write_all = true; } } } @@ -663,6 +667,7 @@ analyze_function (struct cgraph_node *fn) #ifdef ENABLE_CHECKING tree step; #endif + ipa_reference_local_vars_info_t local; if (dump_file) fprintf (dump_file, "\n local analysis of %s\n", cgraph_node_name (fn)); @@ -697,6 +702,21 @@ analyze_function (struct cgraph_node *fn) scan_stmt_for_static_refs (&gsi, fn); } + local = get_reference_vars_info (fn)->local; + if ((flags_from_decl_or_type (decl) & (ECF_NOTHROW | ECF_NORETURN)) + == (ECF_NOTHROW | ECF_NORETURN)) + { + local->calls_write_all = false; + bitmap_clear (local->statics_written); + } + + /* Free bitmaps of direct references if we can not use them anyway. */ + if (local->calls_write_all) + BITMAP_FREE (local->statics_written); + if (local->calls_read_all) + BITMAP_FREE (local->statics_read); + + #ifdef ENABLE_CHECKING /* Verify that all local initializers was expanded by gimplifier. */ for (step = DECL_STRUCT_FUNCTION (decl)->local_decls; @@ -956,10 +976,12 @@ generate_summary (void) removed from the local maps. This will include all of the variables that were found to escape in the function scanning. */ - bitmap_and_into (l->statics_read, - all_module_statics); - bitmap_and_into (l->statics_written, - all_module_statics); + if (l->statics_read) + bitmap_and_into (l->statics_read, + all_module_statics); + if (l->statics_written) + bitmap_and_into (l->statics_written, + all_module_statics); } BITMAP_FREE(module_statics_readonly); @@ -978,19 +1000,21 @@ generate_summary (void) "\nFunction name:%s/%i:", cgraph_node_name (node), node->uid); fprintf (dump_file, "\n locals read: "); - EXECUTE_IF_SET_IN_BITMAP (l->statics_read, - 0, index, bi) - { - fprintf (dump_file, "%s ", - get_static_name (index)); - } + if (l->statics_read) + EXECUTE_IF_SET_IN_BITMAP (l->statics_read, + 0, index, bi) + { + fprintf (dump_file, "%s ", + get_static_name (index)); + } fprintf (dump_file, "\n locals written: "); - EXECUTE_IF_SET_IN_BITMAP (l->statics_written, - 0, index, bi) - { - fprintf(dump_file, "%s ", - get_static_name (index)); - } + if (l->statics_written) + EXECUTE_IF_SET_IN_BITMAP (l->statics_written, + 0, index, bi) + { + fprintf(dump_file, "%s ", + get_static_name (index)); + } if (l->calls_read_all) fprintf (dump_file, "\n calls read all: "); if (l->calls_write_all) @@ -1128,7 +1152,7 @@ ipa_reference_read_summary (void) /* Set the statics written. */ v_count = lto_input_sleb128 (ib); if (v_count == -1) - l->calls_read_all = true; + l->calls_write_all = true; else for (j = 0; j < (unsigned int)v_count; j++) { @@ -1165,7 +1189,11 @@ read_write_all_from_decl (tree decl, bool * read_all, bool * write_all) Indirect calls hsould be only counted and as inliner is replacing them by direct calls, we can conclude if any indirect calls are left in body */ *read_all = true; - *write_all = true; + /* When function does not reutrn, it is safe to ignore anythign it writes + to, because the effect will never happen. */ + if ((flags & (ECF_NOTHROW | ECF_NORETURN)) + != (ECF_NOTHROW | ECF_NORETURN)) + *write_all = true; } } @@ -1336,19 +1364,21 @@ propagate (void) "\nFunction name:%s/%i:", cgraph_node_name (node), node->uid); fprintf (dump_file, "\n locals read: "); - EXECUTE_IF_SET_IN_BITMAP (node_l->statics_read, - 0, index, bi) - { - fprintf (dump_file, "%s ", - get_static_name (index)); - } + if (node_l->statics_read) + EXECUTE_IF_SET_IN_BITMAP (node_l->statics_read, + 0, index, bi) + { + fprintf (dump_file, "%s ", + get_static_name (index)); + } fprintf (dump_file, "\n locals written: "); - EXECUTE_IF_SET_IN_BITMAP (node_l->statics_written, - 0, index, bi) - { - fprintf(dump_file, "%s ", - get_static_name (index)); - } + if (node_l->statics_written) + EXECUTE_IF_SET_IN_BITMAP (node_l->statics_written, + 0, index, bi) + { + fprintf(dump_file, "%s ", + get_static_name (index)); + } w_info = (struct ipa_dfs_info *) node->aux; w = w_info->next_cycle; @@ -1380,19 +1410,25 @@ propagate (void) w = w_info->next_cycle; } fprintf (dump_file, "\n globals read: "); - EXECUTE_IF_SET_IN_BITMAP (node_g->statics_read, - 0, index, bi) - { - fprintf (dump_file, "%s ", - get_static_name (index)); - } + if (node_g->statics_read == all_module_statics) + fprintf (dump_file, "ALL"); + else + EXECUTE_IF_SET_IN_BITMAP (node_g->statics_read, + 0, index, bi) + { + fprintf (dump_file, "%s ", + get_static_name (index)); + } fprintf (dump_file, "\n globals written: "); - EXECUTE_IF_SET_IN_BITMAP (node_g->statics_written, - 0, index, bi) - { - fprintf (dump_file, "%s ", - get_static_name (index)); - } + if (node_g->statics_written == all_module_statics) + fprintf (dump_file, "ALL"); + else + EXECUTE_IF_SET_IN_BITMAP (node_g->statics_written, + 0, index, bi) + { + fprintf (dump_file, "%s ", + get_static_name (index)); + } } }