From patchwork Mon Jul 5 21:56:29 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Hubicka X-Patchwork-Id: 57931 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) by ozlabs.org (Postfix) with SMTP id 1A580B6EF1 for ; Tue, 6 Jul 2010 07:56:41 +1000 (EST) Received: (qmail 16604 invoked by alias); 5 Jul 2010 21:56:39 -0000 Received: (qmail 16593 invoked by uid 22791); 5 Jul 2010 21:56:38 -0000 X-SWARE-Spam-Status: No, hits=-1.8 required=5.0 tests=AWL, BAYES_00, TW_FN, T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from nikam-dmz.ms.mff.cuni.cz (HELO nikam.ms.mff.cuni.cz) (195.113.20.16) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Mon, 05 Jul 2010 21:56:32 +0000 Received: from localhost (occam.ms.mff.cuni.cz [195.113.18.121]) by nikam.ms.mff.cuni.cz (Postfix) with ESMTP id BD1539AC7FE; Mon, 5 Jul 2010 23:56:29 +0200 (CEST) Received: by localhost (Postfix, from userid 16202) id B7B1B56419D; Mon, 5 Jul 2010 23:56:29 +0200 (CEST) Date: Mon, 5 Jul 2010 23:56:29 +0200 From: Jan Hubicka To: gcc-patches@gcc.gnu.org, rguenther@suse.de Subject: Rewrite lto symtab streaming Message-ID: <20100705215629.GA13327@kam.mff.cuni.cz> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.18 (2008-05-17) Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Delivered-To: mailing list gcc-patches@gcc.gnu.org Hi, this patch fixes another problem seen in Mozilla build. Here we optimize out comdat function, but its reference stays in function body in debug info. THis makes produce_symtab to output it into symbol table section that makes gold to prevail all other real copies by this non-existent function. This patch rewrites symbol table streaming to walk callgraph, varpool and alias pairs and output only what is really there. Bootstrapped/regtested x86_64-linux, tested on mozilla build, OK? Honza * lto-streamer.c (write_symbol_vec): Rename to ... (write_symbol) ... this one; write only symbol given and when present in cache. Sanity check that what is defined is present in cgraph/varpool with body/finalized decl. (write_symbols_of_kind): Remove. (produce_symtab): Take outputblock and sets; use cgraph/varpool/alias pairs to produce symtab. (produce_asm_for_decls): Update call of produce_symtab; don't do so when doing WPA streaming. Index: lto-streamer-out.c =================================================================== --- lto-streamer-out.c (revision 161847) +++ lto-streamer-out.c (working copy) @@ -2262,155 +2262,158 @@ lto_out_decl_state_written_size (struct } -/* Helper function of write_symbols_of_kind. CACHE is the streamer - cache with all the pickled nodes. STREAM is the stream where to - write the table. V is a vector with the DECLs that should be on - the table. SEEN is a bitmap of symbols written so far. */ +/* Write symbol T into STREAM in CACHE. SEEN specify symbols we wrote so far. + */ static void -write_symbol_vec (struct lto_streamer_cache_d *cache, - struct lto_output_stream *stream, - VEC(tree,heap) *v, bitmap seen) +write_symbol (struct lto_streamer_cache_d *cache, + struct lto_output_stream *stream, + tree t, bitmap seen, bool alias) { - tree t; - int index; + const char *name; + enum gcc_plugin_symbol_kind kind; + enum gcc_plugin_symbol_visibility visibility; + int slot_num; + uint64_t size; + const char *comdat; + + /* None of the following kinds of symbols are needed in the + symbol table. */ + if (!TREE_PUBLIC (t) + || is_builtin_fn (t) + || DECL_ABSTRACT (t) + || TREE_CODE (t) == RESULT_DECL) + return; + + gcc_assert (TREE_CODE (t) == VAR_DECL + || TREE_CODE (t) == FUNCTION_DECL); + + name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (t)); + + /* FIXME lto: this is from assemble_name_raw in varasm.c. For some + architectures we might have to do the same name manipulations that + ASM_OUTPUT_LABELREF does. */ + if (name[0] == '*') + name = &name[1]; + + lto_streamer_cache_lookup (cache, t, &slot_num); + gcc_assert (slot_num >= 0); + + /* Avoid duplicate symbols. */ + if (bitmap_bit_p (seen, slot_num)) + return; + else + bitmap_set_bit (seen, slot_num); - for (index = 0; VEC_iterate(tree, v, index, t); index++) + if (DECL_EXTERNAL (t)) { - const char *name; - enum gcc_plugin_symbol_kind kind; - enum gcc_plugin_symbol_visibility visibility; - int slot_num; - uint64_t size; - const char *comdat; - - /* None of the following kinds of symbols are needed in the - symbol table. */ - if (!TREE_PUBLIC (t) - || is_builtin_fn (t) - || DECL_ABSTRACT (t) - || TREE_CODE (t) == RESULT_DECL) - continue; - - gcc_assert (TREE_CODE (t) == VAR_DECL - || TREE_CODE (t) == FUNCTION_DECL); - - name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (t)); - - /* FIXME lto: this is from assemble_name_raw in varasm.c. For some - architectures we might have to do the same name manipulations that - ASM_OUTPUT_LABELREF does. */ - if (name[0] == '*') - name = &name[1]; - - lto_streamer_cache_lookup (cache, t, &slot_num); - gcc_assert (slot_num >= 0); - - /* Avoid duplicate symbols. */ - if (bitmap_bit_p (seen, slot_num)) - continue; + if (DECL_WEAK (t)) + kind = GCCPK_WEAKUNDEF; else - bitmap_set_bit (seen, slot_num); - - if (DECL_EXTERNAL (t)) - { - if (DECL_WEAK (t)) - kind = GCCPK_WEAKUNDEF; - else - kind = GCCPK_UNDEF; - } - else - { - if (DECL_WEAK (t)) - kind = GCCPK_WEAKDEF; - else if (DECL_COMMON (t)) - kind = GCCPK_COMMON; - else - kind = GCCPK_DEF; - } - - switch (DECL_VISIBILITY(t)) - { - case VISIBILITY_DEFAULT: - visibility = GCCPV_DEFAULT; - break; - case VISIBILITY_PROTECTED: - visibility = GCCPV_PROTECTED; - break; - case VISIBILITY_HIDDEN: - visibility = GCCPV_HIDDEN; - break; - case VISIBILITY_INTERNAL: - visibility = GCCPV_INTERNAL; - break; - } - - if (kind == GCCPK_COMMON - && DECL_SIZE (t) - && TREE_CODE (DECL_SIZE (t)) == INTEGER_CST) - size = (((uint64_t) TREE_INT_CST_HIGH (DECL_SIZE (t))) << 32) - | TREE_INT_CST_LOW (DECL_SIZE (t)); - else - size = 0; - - if (DECL_ONE_ONLY (t)) - comdat = IDENTIFIER_POINTER (DECL_COMDAT_GROUP (t)); + kind = GCCPK_UNDEF; + } + else + { + if (DECL_WEAK (t)) + kind = GCCPK_WEAKDEF; + else if (DECL_COMMON (t)) + kind = GCCPK_COMMON; else - comdat = ""; + kind = GCCPK_DEF; - lto_output_data_stream (stream, name, strlen (name) + 1); - lto_output_data_stream (stream, comdat, strlen (comdat) + 1); - lto_output_data_stream (stream, &kind, 1); - lto_output_data_stream (stream, &visibility, 1); - lto_output_data_stream (stream, &size, 8); - lto_output_data_stream (stream, &slot_num, 4); + /* When something is defined, it should have node attached. */ + gcc_assert (alias || TREE_CODE (t) != VAR_DECL + || varpool_get_node (t)->finalized); + gcc_assert (alias || TREE_CODE (t) != FUNCTION_DECL + || (cgraph_get_node (t) + && cgraph_get_node (t)->analyzed)); } -} - -/* Write IL symbols of KIND. CACHE is the streamer cache with all the - pickled nodes. SEEN is a bitmap of symbols written so far. */ - -static void -write_symbols_of_kind (lto_decl_stream_e_t kind, - struct lto_streamer_cache_d *cache, bitmap seen) -{ - struct lto_out_decl_state *out_state; - struct lto_output_stream stream; - unsigned num_fns = - VEC_length (lto_out_decl_state_ptr, lto_function_decl_states); - unsigned idx; - - memset (&stream, 0, sizeof (stream)); - out_state = lto_get_out_decl_state (); - write_symbol_vec (cache, &stream, out_state->streams[kind].trees, seen); - - for (idx = 0; idx < num_fns; idx++) + switch (DECL_VISIBILITY(t)) { - out_state = - VEC_index (lto_out_decl_state_ptr, lto_function_decl_states, idx); - write_symbol_vec (cache, &stream, out_state->streams[kind].trees, seen); + case VISIBILITY_DEFAULT: + visibility = GCCPV_DEFAULT; + break; + case VISIBILITY_PROTECTED: + visibility = GCCPV_PROTECTED; + break; + case VISIBILITY_HIDDEN: + visibility = GCCPV_HIDDEN; + break; + case VISIBILITY_INTERNAL: + visibility = GCCPV_INTERNAL; + break; } - lto_write_stream (&stream); + if (kind == GCCPK_COMMON + && DECL_SIZE (t) + && TREE_CODE (DECL_SIZE (t)) == INTEGER_CST) + size = (((uint64_t) TREE_INT_CST_HIGH (DECL_SIZE (t))) << 32) + | TREE_INT_CST_LOW (DECL_SIZE (t)); + else + size = 0; + + if (DECL_ONE_ONLY (t)) + comdat = IDENTIFIER_POINTER (DECL_COMDAT_GROUP (t)); + else + comdat = ""; + + lto_output_data_stream (stream, name, strlen (name) + 1); + lto_output_data_stream (stream, comdat, strlen (comdat) + 1); + lto_output_data_stream (stream, &kind, 1); + lto_output_data_stream (stream, &visibility, 1); + lto_output_data_stream (stream, &size, 8); + lto_output_data_stream (stream, &slot_num, 4); } -/* Write an IL symbol table. CACHE is the streamer cache with all the - pickled nodes. */ +/* Write an IL symbol table to OB. */ static void -produce_symtab (struct lto_streamer_cache_d *cache) +produce_symtab (struct output_block *ob, + cgraph_node_set set, varpool_node_set vset) { + struct lto_streamer_cache_d *cache = ob->writer_cache; char *section_name = lto_get_section_name (LTO_section_symtab, NULL); bitmap seen; + struct cgraph_node *node, *alias; + struct varpool_node *vnode, *valias; + struct lto_output_stream stream; + lto_varpool_encoder_t varpool_encoder = ob->decl_state->varpool_node_encoder; + lto_cgraph_encoder_t encoder = ob->decl_state->cgraph_node_encoder; + int i; + alias_pair *p; lto_begin_section (section_name, false); free (section_name); seen = lto_bitmap_alloc (); - write_symbols_of_kind (LTO_DECL_STREAM_FN_DECL, cache, seen); - write_symbols_of_kind (LTO_DECL_STREAM_VAR_DECL, cache, seen); + memset (&stream, 0, sizeof (stream)); + + /* Write all functions. */ + for (i = 0; i < lto_cgraph_encoder_size (encoder); i++) + { + node = lto_cgraph_encoder_deref (encoder, i); + write_symbol (cache, &stream, node->decl, seen, false); + for (alias = node->same_body; alias; alias = alias->next) + write_symbol (cache, &stream, alias->decl, seen, true); + } + + /* Write all variables. */ + for (i = 0; i < lto_varpool_encoder_size (varpool_encoder); i++) + { + vnode = lto_varpool_encoder_deref (varpool_encoder, i); + write_symbol (cache, &stream, vnode->decl, seen, false); + for (valias = vnode->extra_name; valias; valias = valias->next) + write_symbol (cache, &stream, valias->decl, seen, true); + } + + /* Write all aliases. */ + for (i = 0; VEC_iterate (alias_pair, alias_pairs, i, p); i++) + if (output_alias_pair_p (p, set, vset)) + write_symbol (cache, &stream, p->decl, seen, true); + + lto_write_stream (&stream); lto_bitmap_free (seen); lto_end_section (); @@ -2513,8 +2516,10 @@ produce_asm_for_decls (cgraph_node_set s lto_end_section (); - /* Write the symbol table. */ - produce_symtab (ob->writer_cache); + /* Write the symbol table. It is used by linker to determine dependencies + and thus we can skip it for WPA. */ + if (!flag_wpa) + produce_symtab (ob, set, vset); /* Write command line opts. */ lto_write_options ();