| /* Output variables, constants and external declarations, for GNU compiler. |
| Copyright (C) 1987-2021 Free Software Foundation, Inc. |
| |
| This file is part of GCC. |
| |
| GCC is free software; you can redistribute it and/or modify it under |
| the terms of the GNU General Public License as published by the Free |
| Software Foundation; either version 3, or (at your option) any later |
| version. |
| |
| GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
| WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GCC; see the file COPYING3. If not see |
| <http://www.gnu.org/licenses/>. */ |
| |
| |
| /* This file handles generation of all the assembler code |
| *except* the instructions of a function. |
| This includes declarations of variables and their initial values. |
| |
| We also output the assembler code for constants stored in memory |
| and are responsible for combining constants with the same value. */ |
| |
| #include "config.h" |
| #include "system.h" |
| #include "coretypes.h" |
| #include "backend.h" |
| #include "target.h" |
| #include "rtl.h" |
| #include "tree.h" |
| #include "predict.h" |
| #include "memmodel.h" |
| #include "tm_p.h" |
| #include "stringpool.h" |
| #include "regs.h" |
| #include "emit-rtl.h" |
| #include "cgraph.h" |
| #include "diagnostic-core.h" |
| #include "fold-const.h" |
| #include "stor-layout.h" |
| #include "varasm.h" |
| #include "version.h" |
| #include "flags.h" |
| #include "stmt.h" |
| #include "expr.h" |
| #include "expmed.h" |
| #include "optabs.h" |
| #include "output.h" |
| #include "langhooks.h" |
| #include "debug.h" |
| #include "common/common-target.h" |
| #include "stringpool.h" |
| #include "attribs.h" |
| #include "asan.h" |
| #include "rtl-iter.h" |
| #include "file-prefix-map.h" /* remap_debug_filename() */ |
| #include "alloc-pool.h" |
| #include "toplev.h" |
| #include "opts.h" |
| |
| #ifdef XCOFF_DEBUGGING_INFO |
| #include "xcoffout.h" /* Needed for external data declarations. */ |
| #endif |
| |
| /* The (assembler) name of the first globally-visible object output. */ |
| extern GTY(()) const char *first_global_object_name; |
| extern GTY(()) const char *weak_global_object_name; |
| |
| const char *first_global_object_name; |
| const char *weak_global_object_name; |
| |
| class addr_const; |
| class constant_descriptor_rtx; |
| struct rtx_constant_pool; |
| |
| #define n_deferred_constants (crtl->varasm.deferred_constants) |
| |
| /* Number for making the label on the next |
| constant that is stored in memory. */ |
| |
| static GTY(()) int const_labelno; |
| |
| /* Carry information from ASM_DECLARE_OBJECT_NAME |
| to ASM_FINISH_DECLARE_OBJECT. */ |
| |
| int size_directive_output; |
| |
| /* The last decl for which assemble_variable was called, |
| if it did ASM_DECLARE_OBJECT_NAME. |
| If the last call to assemble_variable didn't do that, |
| this holds 0. */ |
| |
| tree last_assemble_variable_decl; |
| |
| /* The following global variable indicates if the first basic block |
| in a function belongs to the cold partition or not. */ |
| |
| bool first_function_block_is_cold; |
| |
| /* Whether we saw any functions with no_split_stack. */ |
| |
| static bool saw_no_split_stack; |
| |
| static const char *strip_reg_name (const char *); |
| static int contains_pointers_p (tree); |
| #ifdef ASM_OUTPUT_EXTERNAL |
| static bool incorporeal_function_p (tree); |
| #endif |
| static void decode_addr_const (tree, class addr_const *); |
| static hashval_t const_hash_1 (const tree); |
| static int compare_constant (const tree, const tree); |
| static void output_constant_def_contents (rtx); |
| static void output_addressed_constants (tree, int); |
| static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT, |
| unsigned int, bool, bool); |
| static void globalize_decl (tree); |
| static bool decl_readonly_section_1 (enum section_category); |
| #ifdef BSS_SECTION_ASM_OP |
| #ifdef ASM_OUTPUT_ALIGNED_BSS |
| static void asm_output_aligned_bss (FILE *, tree, const char *, |
| unsigned HOST_WIDE_INT, int) |
| ATTRIBUTE_UNUSED; |
| #endif |
| #endif /* BSS_SECTION_ASM_OP */ |
| static void mark_weak (tree); |
| static void output_constant_pool (const char *, tree); |
| static void handle_vtv_comdat_section (section *, const_tree); |
| |
| /* Well-known sections, each one associated with some sort of *_ASM_OP. */ |
| section *text_section; |
| section *data_section; |
| section *readonly_data_section; |
| section *sdata_section; |
| section *ctors_section; |
| section *dtors_section; |
| section *bss_section; |
| section *sbss_section; |
| |
| /* Various forms of common section. All are guaranteed to be nonnull. */ |
| section *tls_comm_section; |
| section *comm_section; |
| section *lcomm_section; |
| |
| /* A SECTION_NOSWITCH section used for declaring global BSS variables. |
| May be null. */ |
| section *bss_noswitch_section; |
| |
| /* The section that holds the main exception table, when known. The section |
| is set either by the target's init_sections hook or by the first call to |
| switch_to_exception_section. */ |
| section *exception_section; |
| |
| /* The section that holds the DWARF2 frame unwind information, when known. |
| The section is set either by the target's init_sections hook or by the |
| first call to switch_to_eh_frame_section. */ |
| section *eh_frame_section; |
| |
| /* asm_out_file's current section. This is NULL if no section has yet |
| been selected or if we lose track of what the current section is. */ |
| section *in_section; |
| |
| /* True if code for the current function is currently being directed |
| at the cold section. */ |
| bool in_cold_section_p; |
| |
| /* The following global holds the "function name" for the code in the |
| cold section of a function, if hot/cold function splitting is enabled |
| and there was actually code that went into the cold section. A |
| pseudo function name is needed for the cold section of code for some |
| debugging tools that perform symbolization. */ |
| tree cold_function_name = NULL_TREE; |
| |
| /* A linked list of all the unnamed sections. */ |
| static GTY(()) section *unnamed_sections; |
| |
| /* Return a nonzero value if DECL has a section attribute. */ |
| #define IN_NAMED_SECTION(DECL) \ |
| (VAR_OR_FUNCTION_DECL_P (DECL) && DECL_SECTION_NAME (DECL) != NULL) |
| |
| struct section_hasher : ggc_ptr_hash<section> |
| { |
| typedef const char *compare_type; |
| |
| static hashval_t hash (section *); |
| static bool equal (section *, const char *); |
| }; |
| |
| /* Hash table of named sections. */ |
| static GTY(()) hash_table<section_hasher> *section_htab; |
| |
| struct object_block_hasher : ggc_ptr_hash<object_block> |
| { |
| typedef const section *compare_type; |
| |
| static hashval_t hash (object_block *); |
| static bool equal (object_block *, const section *); |
| }; |
| |
| /* A table of object_blocks, indexed by section. */ |
| static GTY(()) hash_table<object_block_hasher> *object_block_htab; |
| |
| /* The next number to use for internal anchor labels. */ |
| static GTY(()) int anchor_labelno; |
| |
| /* A pool of constants that can be shared between functions. */ |
| static GTY(()) struct rtx_constant_pool *shared_constant_pool; |
| |
| /* Helper routines for maintaining section_htab. */ |
| |
| bool |
| section_hasher::equal (section *old, const char *new_name) |
| { |
| return strcmp (old->named.name, new_name) == 0; |
| } |
| |
| hashval_t |
| section_hasher::hash (section *old) |
| { |
| return htab_hash_string (old->named.name); |
| } |
| |
| /* Return a hash value for section SECT. */ |
| |
| static hashval_t |
| hash_section (section *sect) |
| { |
| if (sect->common.flags & SECTION_NAMED) |
| return htab_hash_string (sect->named.name); |
| return sect->common.flags & ~SECTION_DECLARED; |
| } |
| |
| /* Helper routines for maintaining object_block_htab. */ |
| |
| inline bool |
| object_block_hasher::equal (object_block *old, const section *new_section) |
| { |
| return old->sect == new_section; |
| } |
| |
| hashval_t |
| object_block_hasher::hash (object_block *old) |
| { |
| return hash_section (old->sect); |
| } |
| |
| /* Return a new unnamed section with the given fields. */ |
| |
| section * |
| get_unnamed_section (unsigned int flags, void (*callback) (const void *), |
| const void *data) |
| { |
| section *sect; |
| |
| sect = ggc_alloc<section> (); |
| sect->unnamed.common.flags = flags | SECTION_UNNAMED; |
| sect->unnamed.callback = callback; |
| sect->unnamed.data = data; |
| sect->unnamed.next = unnamed_sections; |
| |
| unnamed_sections = sect; |
| return sect; |
| } |
| |
| /* Return a SECTION_NOSWITCH section with the given fields. */ |
| |
| static section * |
| get_noswitch_section (unsigned int flags, noswitch_section_callback callback) |
| { |
| section *sect; |
| |
| sect = ggc_alloc<section> (); |
| sect->noswitch.common.flags = flags | SECTION_NOSWITCH; |
| sect->noswitch.callback = callback; |
| |
| return sect; |
| } |
| |
| /* Return the named section structure associated with NAME. Create |
| a new section with the given fields if no such structure exists. |
| When NOT_EXISTING, then fail if the section already exists. Return |
| the existing section if the SECTION_RETAIN bit doesn't match. Set |
| the SECTION_WRITE | SECTION_RELRO bits on the the existing section |
| if one of the section flags is SECTION_WRITE | SECTION_RELRO and the |
| other has none of these flags in named sections and either the section |
| hasn't been declared yet or has been declared as writable. */ |
| |
| section * |
| get_section (const char *name, unsigned int flags, tree decl, |
| bool not_existing) |
| { |
| section *sect, **slot; |
| |
| slot = section_htab->find_slot_with_hash (name, htab_hash_string (name), |
| INSERT); |
| flags |= SECTION_NAMED; |
| if (decl != nullptr |
| && DECL_P (decl) |
| && lookup_attribute ("retain", DECL_ATTRIBUTES (decl))) |
| flags |= SECTION_RETAIN; |
| if (*slot == NULL) |
| { |
| sect = ggc_alloc<section> (); |
| sect->named.common.flags = flags; |
| sect->named.name = ggc_strdup (name); |
| sect->named.decl = decl; |
| *slot = sect; |
| } |
| else |
| { |
| if (not_existing) |
| internal_error ("Section already exists: %qs", name); |
| |
| sect = *slot; |
| /* It is fine if one of the sections has SECTION_NOTYPE as long as |
| the other has none of the contrary flags (see the logic at the end |
| of default_section_type_flags, below). */ |
| if (((sect->common.flags ^ flags) & SECTION_NOTYPE) |
| && !((sect->common.flags | flags) |
| & (SECTION_CODE | SECTION_BSS | SECTION_TLS | SECTION_ENTSIZE |
| | (HAVE_COMDAT_GROUP ? SECTION_LINKONCE : 0)))) |
| { |
| sect->common.flags |= SECTION_NOTYPE; |
| flags |= SECTION_NOTYPE; |
| } |
| if ((sect->common.flags & ~SECTION_DECLARED) != flags |
| && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0) |
| { |
| /* It is fine if one of the section flags is |
| SECTION_WRITE | SECTION_RELRO and the other has none of these |
| flags (i.e. read-only) in named sections and either the |
| section hasn't been declared yet or has been declared as writable. |
| In that case just make sure the resulting flags are |
| SECTION_WRITE | SECTION_RELRO, ie. writable only because of |
| relocations. */ |
| if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO)) |
| == (SECTION_WRITE | SECTION_RELRO) |
| && (sect->common.flags |
| & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO)) |
| == (flags & ~(SECTION_WRITE | SECTION_RELRO)) |
| && ((sect->common.flags & SECTION_DECLARED) == 0 |
| || (sect->common.flags & SECTION_WRITE))) |
| { |
| sect->common.flags |= (SECTION_WRITE | SECTION_RELRO); |
| return sect; |
| } |
| /* If the SECTION_RETAIN bit doesn't match, return and switch |
| to a new section later. */ |
| if ((sect->common.flags & SECTION_RETAIN) |
| != (flags & SECTION_RETAIN)) |
| return sect; |
| /* Sanity check user variables for flag changes. */ |
| if (sect->named.decl != NULL |
| && DECL_P (sect->named.decl) |
| && decl != sect->named.decl) |
| { |
| if (decl != NULL && DECL_P (decl)) |
| error ("%+qD causes a section type conflict with %qD", |
| decl, sect->named.decl); |
| else |
| error ("section type conflict with %qD", sect->named.decl); |
| inform (DECL_SOURCE_LOCATION (sect->named.decl), |
| "%qD was declared here", sect->named.decl); |
| } |
| else if (decl != NULL && DECL_P (decl)) |
| error ("%+qD causes a section type conflict", decl); |
| else |
| error ("section type conflict"); |
| /* Make sure we don't error about one section multiple times. */ |
| sect->common.flags |= SECTION_OVERRIDE; |
| } |
| } |
| return sect; |
| } |
| |
| /* Return true if the current compilation mode benefits from having |
| objects grouped into blocks. */ |
| |
| static bool |
| use_object_blocks_p (void) |
| { |
| return flag_section_anchors; |
| } |
| |
| /* Return the object_block structure for section SECT. Create a new |
| structure if we haven't created one already. Return null if SECT |
| itself is null. Return also null for mergeable sections since |
| section anchors can't be used in mergeable sections anyway, |
| because the linker might move objects around, and using the |
| object blocks infrastructure in that case is both a waste and a |
| maintenance burden. */ |
| |
| static struct object_block * |
| get_block_for_section (section *sect) |
| { |
| struct object_block *block; |
| |
| if (sect == NULL) |
| return NULL; |
| |
| if (sect->common.flags & SECTION_MERGE) |
| return NULL; |
| |
| object_block **slot |
| = object_block_htab->find_slot_with_hash (sect, hash_section (sect), |
| INSERT); |
| block = *slot; |
| if (block == NULL) |
| { |
| block = ggc_cleared_alloc<object_block> (); |
| block->sect = sect; |
| *slot = block; |
| } |
| return block; |
| } |
| |
| /* Create a symbol with label LABEL and place it at byte offset |
| OFFSET in BLOCK. OFFSET can be negative if the symbol's offset |
| is not yet known. LABEL must be a garbage-collected string. */ |
| |
| static rtx |
| create_block_symbol (const char *label, struct object_block *block, |
| HOST_WIDE_INT offset) |
| { |
| rtx symbol; |
| unsigned int size; |
| |
| /* Create the extended SYMBOL_REF. */ |
| size = RTX_HDR_SIZE + sizeof (struct block_symbol); |
| symbol = (rtx) ggc_internal_alloc (size); |
| |
| /* Initialize the normal SYMBOL_REF fields. */ |
| memset (symbol, 0, size); |
| PUT_CODE (symbol, SYMBOL_REF); |
| PUT_MODE (symbol, Pmode); |
| XSTR (symbol, 0) = label; |
| SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO; |
| |
| /* Initialize the block_symbol stuff. */ |
| SYMBOL_REF_BLOCK (symbol) = block; |
| SYMBOL_REF_BLOCK_OFFSET (symbol) = offset; |
| |
| return symbol; |
| } |
| |
| /* Return a section with a particular name and with whatever SECTION_* |
| flags section_type_flags deems appropriate. The name of the section |
| is taken from NAME if nonnull, otherwise it is taken from DECL's |
| DECL_SECTION_NAME. DECL is the decl associated with the section |
| (see the section comment for details) and RELOC is as for |
| section_type_flags. */ |
| |
| section * |
| get_named_section (tree decl, const char *name, int reloc) |
| { |
| unsigned int flags; |
| |
| if (name == NULL) |
| { |
| gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl)); |
| name = DECL_SECTION_NAME (decl); |
| } |
| |
| flags = targetm.section_type_flags (decl, name, reloc); |
| return get_section (name, flags, decl); |
| } |
| |
| /* Worker for resolve_unique_section. */ |
| |
| static bool |
| set_implicit_section (struct symtab_node *n, void *data ATTRIBUTE_UNUSED) |
| { |
| n->implicit_section = true; |
| return false; |
| } |
| |
| /* If required, set DECL_SECTION_NAME to a unique name. */ |
| |
| void |
| resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED, |
| int flag_function_or_data_sections) |
| { |
| if (DECL_SECTION_NAME (decl) == NULL |
| && targetm_common.have_named_sections |
| && (flag_function_or_data_sections |
| || lookup_attribute ("retain", DECL_ATTRIBUTES (decl)) |
| || DECL_COMDAT_GROUP (decl))) |
| { |
| targetm.asm_out.unique_section (decl, reloc); |
| if (DECL_SECTION_NAME (decl)) |
| symtab_node::get (decl)->call_for_symbol_and_aliases |
| (set_implicit_section, NULL, true); |
| } |
| } |
| |
| #ifdef BSS_SECTION_ASM_OP |
| |
| #ifdef ASM_OUTPUT_ALIGNED_BSS |
| |
| /* Utility function for targets to use in implementing |
| ASM_OUTPUT_ALIGNED_BSS. |
| ??? It is believed that this function will work in most cases so such |
| support is localized here. */ |
| |
| static void |
| asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED, |
| const char *name, unsigned HOST_WIDE_INT size, |
| int align) |
| { |
| switch_to_section (bss_section); |
| ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT)); |
| #ifdef ASM_DECLARE_OBJECT_NAME |
| last_assemble_variable_decl = decl; |
| ASM_DECLARE_OBJECT_NAME (file, name, decl); |
| #else |
| /* Standard thing is just output label for the object. */ |
| ASM_OUTPUT_LABEL (file, name); |
| #endif /* ASM_DECLARE_OBJECT_NAME */ |
| ASM_OUTPUT_SKIP (file, size ? size : 1); |
| } |
| |
| #endif |
| |
| #endif /* BSS_SECTION_ASM_OP */ |
| |
| #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS |
| /* Return the hot section for function DECL. Return text_section for |
| null DECLs. */ |
| |
| static section * |
| hot_function_section (tree decl) |
| { |
| if (decl != NULL_TREE |
| && DECL_SECTION_NAME (decl) != NULL |
| && targetm_common.have_named_sections) |
| return get_named_section (decl, NULL, 0); |
| else |
| return text_section; |
| } |
| #endif |
| |
| /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL) |
| is NULL. |
| |
| When DECL_SECTION_NAME is non-NULL and it is implicit section and |
| NAMED_SECTION_SUFFIX is non-NULL, then produce section called |
| concatenate the name with NAMED_SECTION_SUFFIX. |
| Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */ |
| |
| section * |
| get_named_text_section (tree decl, |
| const char *text_section_name, |
| const char *named_section_suffix) |
| { |
| if (decl && DECL_SECTION_NAME (decl)) |
| { |
| if (named_section_suffix) |
| { |
| const char *dsn = DECL_SECTION_NAME (decl); |
| const char *stripped_name; |
| char *name, *buffer; |
| |
| name = (char *) alloca (strlen (dsn) + 1); |
| memcpy (name, dsn, |
| strlen (dsn) + 1); |
| |
| stripped_name = targetm.strip_name_encoding (name); |
| |
| buffer = ACONCAT ((stripped_name, named_section_suffix, NULL)); |
| return get_named_section (decl, buffer, 0); |
| } |
| else if (symtab_node::get (decl)->implicit_section) |
| { |
| const char *name; |
| |
| /* Do not try to split gnu_linkonce functions. This gets somewhat |
| slipperly. */ |
| if (DECL_COMDAT_GROUP (decl) && !HAVE_COMDAT_GROUP) |
| return NULL; |
| name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); |
| name = targetm.strip_name_encoding (name); |
| return get_named_section (decl, ACONCAT ((text_section_name, ".", |
| name, NULL)), 0); |
| } |
| else |
| return NULL; |
| } |
| return get_named_section (decl, text_section_name, 0); |
| } |
| |
| /* Choose named function section based on its frequency. */ |
| |
| section * |
| default_function_section (tree decl, enum node_frequency freq, |
| bool startup, bool exit) |
| { |
| #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG |
| /* Old GNU linkers have buggy --gc-section support, which sometimes |
| results in .gcc_except_table* sections being garbage collected. */ |
| if (decl |
| && symtab_node::get (decl)->implicit_section) |
| return NULL; |
| #endif |
| |
| if (!flag_reorder_functions |
| || !targetm_common.have_named_sections) |
| return NULL; |
| /* Startup code should go to startup subsection unless it is |
| unlikely executed (this happens especially with function splitting |
| where we can split away unnecessary parts of static constructors. */ |
| if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED) |
| { |
| /* During LTO the tp_first_run profiling will naturally place all |
| initialization code first. Using separate section is counter-productive |
| because startup only code may call functions which are no longer |
| startup only. */ |
| if (!in_lto_p |
| || !cgraph_node::get (decl)->tp_first_run |
| || !opt_for_fn (decl, flag_profile_reorder_functions)) |
| return get_named_text_section (decl, ".text.startup", NULL); |
| else |
| return NULL; |
| } |
| |
| /* Similarly for exit. */ |
| if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED) |
| return get_named_text_section (decl, ".text.exit", NULL); |
| |
| /* Group cold functions together, similarly for hot code. */ |
| switch (freq) |
| { |
| case NODE_FREQUENCY_UNLIKELY_EXECUTED: |
| return get_named_text_section (decl, ".text.unlikely", NULL); |
| case NODE_FREQUENCY_HOT: |
| return get_named_text_section (decl, ".text.hot", NULL); |
| /* FALLTHRU */ |
| default: |
| return NULL; |
| } |
| } |
| |
| /* Return the section for function DECL. |
| |
| If DECL is NULL_TREE, return the text section. We can be passed |
| NULL_TREE under some circumstances by dbxout.c at least. |
| |
| If FORCE_COLD is true, return cold function section ignoring |
| the frequency info of cgraph_node. */ |
| |
| static section * |
| function_section_1 (tree decl, bool force_cold) |
| { |
| section *section = NULL; |
| enum node_frequency freq = NODE_FREQUENCY_NORMAL; |
| bool startup = false, exit = false; |
| |
| if (decl) |
| { |
| struct cgraph_node *node = cgraph_node::get (decl); |
| |
| if (node) |
| { |
| freq = node->frequency; |
| startup = node->only_called_at_startup; |
| exit = node->only_called_at_exit; |
| } |
| } |
| if (force_cold) |
| freq = NODE_FREQUENCY_UNLIKELY_EXECUTED; |
| |
| #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS |
| if (decl != NULL_TREE |
| && DECL_SECTION_NAME (decl) != NULL) |
| { |
| if (targetm.asm_out.function_section) |
| section = targetm.asm_out.function_section (decl, freq, |
| startup, exit); |
| if (section) |
| return section; |
| return get_named_section (decl, NULL, 0); |
| } |
| else |
| return targetm.asm_out.select_section |
| (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED, |
| symtab_node::get (decl)->definition_alignment ()); |
| #else |
| if (targetm.asm_out.function_section) |
| section = targetm.asm_out.function_section (decl, freq, startup, exit); |
| if (section) |
| return section; |
| return hot_function_section (decl); |
| #endif |
| } |
| |
| /* Return the section for function DECL. |
| |
| If DECL is NULL_TREE, return the text section. We can be passed |
| NULL_TREE under some circumstances by dbxout.c at least. */ |
| |
| section * |
| function_section (tree decl) |
| { |
| /* Handle cases where function splitting code decides |
| to put function entry point into unlikely executed section |
| despite the fact that the function itself is not cold |
| (i.e. it is called rarely but contains a hot loop that is |
| better to live in hot subsection for the code locality). */ |
| return function_section_1 (decl, |
| first_function_block_is_cold); |
| } |
| |
| /* Return the section for the current function, take IN_COLD_SECTION_P |
| into account. */ |
| |
| section * |
| current_function_section (void) |
| { |
| return function_section_1 (current_function_decl, in_cold_section_p); |
| } |
| |
| /* Tell assembler to switch to unlikely-to-be-executed text section. */ |
| |
| section * |
| unlikely_text_section (void) |
| { |
| return function_section_1 (current_function_decl, true); |
| } |
| |
| /* When called within a function context, return true if the function |
| has been assigned a cold text section and if SECT is that section. |
| When called outside a function context, return true if SECT is the |
| default cold section. */ |
| |
| bool |
| unlikely_text_section_p (section *sect) |
| { |
| return sect == function_section_1 (current_function_decl, true); |
| } |
| |
| /* Switch to the other function partition (if inside of hot section |
| into cold section, otherwise into the hot section). */ |
| |
| void |
| switch_to_other_text_partition (void) |
| { |
| in_cold_section_p = !in_cold_section_p; |
| switch_to_section (current_function_section ()); |
| } |
| |
| /* Return the read-only or relocated read-only data section |
| associated with function DECL. */ |
| |
| section * |
| default_function_rodata_section (tree decl, bool relocatable) |
| { |
| const char* sname; |
| unsigned int flags; |
| |
| flags = 0; |
| |
| if (relocatable) |
| { |
| sname = ".data.rel.ro.local"; |
| flags = (SECTION_WRITE | SECTION_RELRO); |
| } |
| else |
| sname = ".rodata"; |
| |
| if (decl && DECL_SECTION_NAME (decl)) |
| { |
| const char *name = DECL_SECTION_NAME (decl); |
| |
| if (DECL_COMDAT_GROUP (decl) && HAVE_COMDAT_GROUP) |
| { |
| const char *dot; |
| size_t len; |
| char* rname; |
| |
| dot = strchr (name + 1, '.'); |
| if (!dot) |
| dot = name; |
| len = strlen (dot) + strlen (sname) + 1; |
| rname = (char *) alloca (len); |
| |
| strcpy (rname, sname); |
| strcat (rname, dot); |
| return get_section (rname, (SECTION_LINKONCE | flags), decl); |
| } |
| /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo or |
| .gnu.linkonce.d.rel.ro.local.foo if the jump table is relocatable. */ |
| else if (DECL_COMDAT_GROUP (decl) |
| && strncmp (name, ".gnu.linkonce.t.", 16) == 0) |
| { |
| size_t len; |
| char *rname; |
| |
| if (relocatable) |
| { |
| len = strlen (name) + strlen (".rel.ro.local") + 1; |
| rname = (char *) alloca (len); |
| |
| strcpy (rname, ".gnu.linkonce.d.rel.ro.local"); |
| strcat (rname, name + 15); |
| } |
| else |
| { |
| len = strlen (name) + 1; |
| rname = (char *) alloca (len); |
| |
| memcpy (rname, name, len); |
| rname[14] = 'r'; |
| } |
| return get_section (rname, (SECTION_LINKONCE | flags), decl); |
| } |
| /* For .text.foo we want to use .rodata.foo. */ |
| else if (flag_function_sections && flag_data_sections |
| && strncmp (name, ".text.", 6) == 0) |
| { |
| size_t len = strlen (name) + 1; |
| char *rname = (char *) alloca (len + strlen (sname) - 5); |
| |
| memcpy (rname, sname, strlen (sname)); |
| memcpy (rname + strlen (sname), name + 5, len - 5); |
| return get_section (rname, flags, decl); |
| } |
| } |
| |
| if (relocatable) |
| return get_section (sname, flags, decl); |
| else |
| return readonly_data_section; |
| } |
| |
| /* Return the read-only data section associated with function DECL |
| for targets where that section should be always the single |
| readonly data section. */ |
| |
| section * |
| default_no_function_rodata_section (tree, bool) |
| { |
| return readonly_data_section; |
| } |
| |
| /* A subroutine of mergeable_string_section and mergeable_constant_section. */ |
| |
| static const char * |
| function_mergeable_rodata_prefix (void) |
| { |
| section *s = targetm.asm_out.function_rodata_section (current_function_decl, |
| false); |
| if (SECTION_STYLE (s) == SECTION_NAMED) |
| return s->named.name; |
| else |
| return targetm.asm_out.mergeable_rodata_prefix; |
| } |
| |
| /* Return the section to use for string merging. */ |
| |
| static section * |
| mergeable_string_section (tree decl ATTRIBUTE_UNUSED, |
| unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED, |
| unsigned int flags ATTRIBUTE_UNUSED) |
| { |
| HOST_WIDE_INT len; |
| |
| if (HAVE_GAS_SHF_MERGE && flag_merge_constants |
| && TREE_CODE (decl) == STRING_CST |
| && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE |
| && align <= 256 |
| && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0 |
| && TREE_STRING_LENGTH (decl) == len) |
| { |
| scalar_int_mode mode; |
| unsigned int modesize; |
| const char *str; |
| HOST_WIDE_INT i; |
| int j, unit; |
| const char *prefix = function_mergeable_rodata_prefix (); |
| char *name = (char *) alloca (strlen (prefix) + 30); |
| |
| mode = SCALAR_INT_TYPE_MODE (TREE_TYPE (TREE_TYPE (decl))); |
| modesize = GET_MODE_BITSIZE (mode); |
| if (modesize >= 8 && modesize <= 256 |
| && (modesize & (modesize - 1)) == 0) |
| { |
| if (align < modesize) |
| align = modesize; |
| |
| if (!HAVE_LD_ALIGNED_SHF_MERGE && align > 8) |
| return readonly_data_section; |
| |
| str = TREE_STRING_POINTER (decl); |
| unit = GET_MODE_SIZE (mode); |
| |
| /* Check for embedded NUL characters. */ |
| for (i = 0; i < len; i += unit) |
| { |
| for (j = 0; j < unit; j++) |
| if (str[i + j] != '\0') |
| break; |
| if (j == unit) |
| break; |
| } |
| if (i == len - unit || (unit == 1 && i == len)) |
| { |
| sprintf (name, "%s.str%d.%d", prefix, |
| modesize / 8, (int) (align / 8)); |
| flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS; |
| return get_section (name, flags, NULL); |
| } |
| } |
| } |
| |
| return readonly_data_section; |
| } |
| |
| /* Return the section to use for constant merging. */ |
| |
| section * |
| mergeable_constant_section (machine_mode mode ATTRIBUTE_UNUSED, |
| unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED, |
| unsigned int flags ATTRIBUTE_UNUSED) |
| { |
| if (HAVE_GAS_SHF_MERGE && flag_merge_constants |
| && mode != VOIDmode |
| && mode != BLKmode |
| && known_le (GET_MODE_BITSIZE (mode), align) |
| && align >= 8 |
| && align <= 256 |
| && (align & (align - 1)) == 0 |
| && (HAVE_LD_ALIGNED_SHF_MERGE ? 1 : align == 8)) |
| { |
| const char *prefix = function_mergeable_rodata_prefix (); |
| char *name = (char *) alloca (strlen (prefix) + 30); |
| |
| sprintf (name, "%s.cst%d", prefix, (int) (align / 8)); |
| flags |= (align / 8) | SECTION_MERGE; |
| return get_section (name, flags, NULL); |
| } |
| return readonly_data_section; |
| } |
| |
| /* Given NAME, a putative register name, discard any customary prefixes. */ |
| |
| static const char * |
| strip_reg_name (const char *name) |
| { |
| #ifdef REGISTER_PREFIX |
| if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX))) |
| name += strlen (REGISTER_PREFIX); |
| #endif |
| if (name[0] == '%' || name[0] == '#') |
| name++; |
| return name; |
| } |
| |
| /* The user has asked for a DECL to have a particular name. Set (or |
| change) it in such a way that we don't prefix an underscore to |
| it. */ |
| void |
| set_user_assembler_name (tree decl, const char *name) |
| { |
| char *starred = (char *) alloca (strlen (name) + 2); |
| starred[0] = '*'; |
| strcpy (starred + 1, name); |
| symtab->change_decl_assembler_name (decl, get_identifier (starred)); |
| SET_DECL_RTL (decl, NULL_RTX); |
| } |
| |
| /* Decode an `asm' spec for a declaration as a register name. |
| Return the register number, or -1 if nothing specified, |
| or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized, |
| or -3 if ASMSPEC is `cc' and is not recognized, |
| or -4 if ASMSPEC is `memory' and is not recognized. |
| Accept an exact spelling or a decimal number. |
| Prefixes such as % are optional. */ |
| |
| int |
| decode_reg_name_and_count (const char *asmspec, int *pnregs) |
| { |
| /* Presume just one register is clobbered. */ |
| *pnregs = 1; |
| |
| if (asmspec != 0) |
| { |
| int i; |
| |
| /* Get rid of confusing prefixes. */ |
| asmspec = strip_reg_name (asmspec); |
| |
| /* Allow a decimal number as a "register name". */ |
| for (i = strlen (asmspec) - 1; i >= 0; i--) |
| if (! ISDIGIT (asmspec[i])) |
| break; |
| if (asmspec[0] != 0 && i < 0) |
| { |
| i = atoi (asmspec); |
| if (i < FIRST_PSEUDO_REGISTER && i >= 0 && reg_names[i][0]) |
| return i; |
| else |
| return -2; |
| } |
| |
| for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) |
| if (reg_names[i][0] |
| && ! strcmp (asmspec, strip_reg_name (reg_names[i]))) |
| return i; |
| |
| #ifdef OVERLAPPING_REGISTER_NAMES |
| { |
| static const struct |
| { |
| const char *const name; |
| const int number; |
| const int nregs; |
| } table[] = OVERLAPPING_REGISTER_NAMES; |
| |
| for (i = 0; i < (int) ARRAY_SIZE (table); i++) |
| if (table[i].name[0] |
| && ! strcmp (asmspec, table[i].name)) |
| { |
| *pnregs = table[i].nregs; |
| return table[i].number; |
| } |
| } |
| #endif /* OVERLAPPING_REGISTER_NAMES */ |
| |
| #ifdef ADDITIONAL_REGISTER_NAMES |
| { |
| static const struct { const char *const name; const int number; } table[] |
| = ADDITIONAL_REGISTER_NAMES; |
| |
| for (i = 0; i < (int) ARRAY_SIZE (table); i++) |
| if (table[i].name[0] |
| && ! strcmp (asmspec, table[i].name) |
| && reg_names[table[i].number][0]) |
| return table[i].number; |
| } |
| #endif /* ADDITIONAL_REGISTER_NAMES */ |
| |
| if (!strcmp (asmspec, "memory")) |
| return -4; |
| |
| if (!strcmp (asmspec, "cc")) |
| return -3; |
| |
| return -2; |
| } |
| |
| return -1; |
| } |
| |
| int |
| decode_reg_name (const char *name) |
| { |
| int count; |
| return decode_reg_name_and_count (name, &count); |
| } |
| |
| |
| /* Return true if DECL's initializer is suitable for a BSS section. */ |
| |
| bool |
| bss_initializer_p (const_tree decl, bool named) |
| { |
| /* Do not put non-common constants into the .bss section, they belong in |
| a readonly section, except when NAMED is true. */ |
| return ((!TREE_READONLY (decl) || DECL_COMMON (decl) || named) |
| && (DECL_INITIAL (decl) == NULL |
| /* In LTO we have no errors in program; error_mark_node is used |
| to mark offlined constructors. */ |
| || (DECL_INITIAL (decl) == error_mark_node |
| && !in_lto_p) |
| || (flag_zero_initialized_in_bss |
| && initializer_zerop (DECL_INITIAL (decl)) |
| /* A decl with the "persistent" attribute applied and |
| explicitly initialized to 0 should not be treated as a BSS |
| variable. */ |
| && !DECL_PERSISTENT_P (decl)))); |
| } |
| |
| /* Compute the alignment of variable specified by DECL. |
| DONT_OUTPUT_DATA is from assemble_variable. */ |
| |
| void |
| align_variable (tree decl, bool dont_output_data) |
| { |
| unsigned int align = DECL_ALIGN (decl); |
| |
| /* In the case for initialing an array whose length isn't specified, |
| where we have not yet been able to do the layout, |
| figure out the proper alignment now. */ |
| if (dont_output_data && DECL_SIZE (decl) == 0 |
| && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE) |
| align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl)))); |
| |
| /* Some object file formats have a maximum alignment which they support. |
| In particular, a.out format supports a maximum alignment of 4. */ |
| if (align > MAX_OFILE_ALIGNMENT) |
| { |
| error ("alignment of %q+D is greater than maximum object " |
| "file alignment %d", decl, |
| MAX_OFILE_ALIGNMENT/BITS_PER_UNIT); |
| align = MAX_OFILE_ALIGNMENT; |
| } |
| |
| if (! DECL_USER_ALIGN (decl)) |
| { |
| #ifdef DATA_ABI_ALIGNMENT |
| unsigned int data_abi_align |
| = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align); |
| /* For backwards compatibility, don't assume the ABI alignment for |
| TLS variables. */ |
| if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD) |
| align = data_abi_align; |
| #endif |
| |
| /* On some machines, it is good to increase alignment sometimes. |
| But as DECL_ALIGN is used both for actually emitting the variable |
| and for code accessing the variable as guaranteed alignment, we |
| can only increase the alignment if it is a performance optimization |
| if the references to it must bind to the current definition. */ |
| if (decl_binds_to_current_def_p (decl) |
| && !DECL_VIRTUAL_P (decl)) |
| { |
| #ifdef DATA_ALIGNMENT |
| unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align); |
| /* Don't increase alignment too much for TLS variables - TLS space |
| is too precious. */ |
| if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD) |
| align = data_align; |
| #endif |
| if (DECL_INITIAL (decl) != 0 |
| /* In LTO we have no errors in program; error_mark_node is used |
| to mark offlined constructors. */ |
| && (in_lto_p || DECL_INITIAL (decl) != error_mark_node)) |
| { |
| unsigned int const_align |
| = targetm.constant_alignment (DECL_INITIAL (decl), align); |
| /* Don't increase alignment too much for TLS variables - TLS |
| space is too precious. */ |
| if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD) |
| align = const_align; |
| } |
| } |
| } |
| |
| /* Reset the alignment in case we have made it tighter, so we can benefit |
| from it in get_pointer_alignment. */ |
| SET_DECL_ALIGN (decl, align); |
| } |
| |
| /* Return DECL_ALIGN (decl), possibly increased for optimization purposes |
| beyond what align_variable returned. */ |
| |
| static unsigned int |
| get_variable_align (tree decl) |
| { |
| unsigned int align = DECL_ALIGN (decl); |
| |
| /* For user aligned vars or static vars align_variable already did |
| everything. */ |
| if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl)) |
| return align; |
| |
| #ifdef DATA_ABI_ALIGNMENT |
| if (DECL_THREAD_LOCAL_P (decl)) |
| align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align); |
| #endif |
| |
| /* For decls that bind to the current definition, align_variable |
| did also everything, except for not assuming ABI required alignment |
| of TLS variables. For other vars, increase the alignment here |
| as an optimization. */ |
| if (!decl_binds_to_current_def_p (decl)) |
| { |
| /* On some machines, it is good to increase alignment sometimes. */ |
| #ifdef DATA_ALIGNMENT |
| unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align); |
| /* Don't increase alignment too much for TLS variables - TLS space |
| is too precious. */ |
| if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD) |
| align = data_align; |
| #endif |
| if (DECL_INITIAL (decl) != 0 |
| /* In LTO we have no errors in program; error_mark_node is used |
| to mark offlined constructors. */ |
| && (in_lto_p || DECL_INITIAL (decl) != error_mark_node)) |
| { |
| unsigned int const_align |
| = targetm.constant_alignment (DECL_INITIAL (decl), align); |
| /* Don't increase alignment too much for TLS variables - TLS space |
| is too precious. */ |
| if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD) |
| align = const_align; |
| } |
| } |
| |
| return align; |
| } |
| |
| /* Return the section into which the given VAR_DECL or CONST_DECL |
| should be placed. PREFER_NOSWITCH_P is true if a noswitch |
| section should be used wherever possible. */ |
| |
| section * |
| get_variable_section (tree decl, bool prefer_noswitch_p) |
| { |
| addr_space_t as = ADDR_SPACE_GENERIC; |
| int reloc; |
| varpool_node *vnode = varpool_node::get (decl); |
| if (vnode) |
| { |
| vnode = vnode->ultimate_alias_target (); |
| decl = vnode->decl; |
| } |
| |
| if (TREE_TYPE (decl) != error_mark_node) |
| as = TYPE_ADDR_SPACE (TREE_TYPE (decl)); |
| |
| /* We need the constructor to figure out reloc flag. */ |
| if (vnode) |
| vnode->get_constructor (); |
| |
| if (DECL_COMMON (decl) |
| && !lookup_attribute ("retain", DECL_ATTRIBUTES (decl))) |
| { |
| /* If the decl has been given an explicit section name, or it resides |
| in a non-generic address space, then it isn't common, and shouldn't |
| be handled as such. */ |
| gcc_assert (DECL_SECTION_NAME (decl) == NULL |
| && ADDR_SPACE_GENERIC_P (as)); |
| if (DECL_THREAD_LOCAL_P (decl)) |
| return tls_comm_section; |
| else if (TREE_PUBLIC (decl) && bss_initializer_p (decl)) |
| return comm_section; |
| } |
| |
| if (DECL_INITIAL (decl) == error_mark_node) |
| reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0; |
| else if (DECL_INITIAL (decl)) |
| reloc = compute_reloc_for_constant (DECL_INITIAL (decl)); |
| else |
| reloc = 0; |
| |
| resolve_unique_section (decl, reloc, flag_data_sections); |
| if (IN_NAMED_SECTION (decl)) |
| { |
| section *sect = get_named_section (decl, NULL, reloc); |
| |
| if ((sect->common.flags & SECTION_BSS) |
| && !bss_initializer_p (decl, true)) |
| { |
| error_at (DECL_SOURCE_LOCATION (decl), |
| "only zero initializers are allowed in section %qs", |
| sect->named.name); |
| DECL_INITIAL (decl) = error_mark_node; |
| } |
| return sect; |
| } |
| |
| if (ADDR_SPACE_GENERIC_P (as) |
| && !DECL_THREAD_LOCAL_P (decl) |
| && !DECL_NOINIT_P (decl) |
| && !(prefer_noswitch_p && targetm.have_switchable_bss_sections) |
| && bss_initializer_p (decl)) |
| { |
| if (!TREE_PUBLIC (decl) |
| && !((flag_sanitize & SANITIZE_ADDRESS) |
| && asan_protect_global (decl))) |
| return lcomm_section; |
| if (bss_noswitch_section) |
| return bss_noswitch_section; |
| } |
| |
| return targetm.asm_out.select_section (decl, reloc, |
| get_variable_align (decl)); |
| } |
| |
| /* Return the block into which object_block DECL should be placed. */ |
| |
| static struct object_block * |
| get_block_for_decl (tree decl) |
| { |
| section *sect; |
| |
| if (VAR_P (decl)) |
| { |
| /* The object must be defined in this translation unit. */ |
| if (DECL_EXTERNAL (decl)) |
| return NULL; |
| |
| /* There's no point using object blocks for something that is |
| isolated by definition. */ |
| if (DECL_COMDAT_GROUP (decl)) |
| return NULL; |
| } |
| |
| /* We can only calculate block offsets if the decl has a known |
| constant size. */ |
| if (DECL_SIZE_UNIT (decl) == NULL) |
| return NULL; |
| if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl))) |
| return NULL; |
| |
| /* Find out which section should contain DECL. We cannot put it into |
| an object block if it requires a standalone definition. */ |
| if (VAR_P (decl)) |
| align_variable (decl, 0); |
| sect = get_variable_section (decl, true); |
| if (SECTION_STYLE (sect) == SECTION_NOSWITCH) |
| return NULL; |
| |
| return get_block_for_section (sect); |
| } |
| |
| /* Make sure block symbol SYMBOL is in block BLOCK. */ |
| |
| static void |
| change_symbol_block (rtx symbol, struct object_block *block) |
| { |
| if (block != SYMBOL_REF_BLOCK (symbol)) |
| { |
| gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0); |
| SYMBOL_REF_BLOCK (symbol) = block; |
| } |
| } |
| |
| /* Return true if it is possible to put DECL in an object_block. */ |
| |
| static bool |
| use_blocks_for_decl_p (tree decl) |
| { |
| struct symtab_node *snode; |
| |
| /* Only data DECLs can be placed into object blocks. */ |
| if (!VAR_P (decl) && TREE_CODE (decl) != CONST_DECL) |
| return false; |
| |
| /* DECL_INITIAL (decl) set to decl is a hack used for some decls that |
| are never used from code directly and we never want object block handling |
| for those. */ |
| if (DECL_INITIAL (decl) == decl) |
| return false; |
| |
| /* If this decl is an alias, then we don't want to emit a |
| definition. */ |
| if (VAR_P (decl) |
| && (snode = symtab_node::get (decl)) != NULL |
| && snode->alias) |
| return false; |
| |
| return targetm.use_blocks_for_decl_p (decl); |
| } |
| |
| /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS |
| until we find an identifier that is not itself a transparent alias. |
| Modify the alias passed to it by reference (and all aliases on the |
| way to the ultimate target), such that they do not have to be |
| followed again, and return the ultimate target of the alias |
| chain. */ |
| |
| static inline tree |
| ultimate_transparent_alias_target (tree *alias) |
| { |
| tree target = *alias; |
| |
| if (IDENTIFIER_TRANSPARENT_ALIAS (target)) |
| { |
| gcc_assert (TREE_CHAIN (target)); |
| target = ultimate_transparent_alias_target (&TREE_CHAIN (target)); |
| gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target) |
| && ! TREE_CHAIN (target)); |
| *alias = target; |
| } |
| |
| return target; |
| } |
| |
| /* Return true if REGNUM is mentioned in ELIMINABLE_REGS as a from |
| register number. */ |
| |
| static bool |
| eliminable_regno_p (int regnum) |
| { |
| static const struct |
| { |
| const int from; |
| const int to; |
| } eliminables[] = ELIMINABLE_REGS; |
| for (size_t i = 0; i < ARRAY_SIZE (eliminables); i++) |
| if (regnum == eliminables[i].from) |
| return true; |
| return false; |
| } |
| |
| /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should |
| have static storage duration. In other words, it should not be an |
| automatic variable, including PARM_DECLs. |
| |
| There is, however, one exception: this function handles variables |
| explicitly placed in a particular register by the user. |
| |
| This is never called for PARM_DECL nodes. */ |
| |
| void |
| make_decl_rtl (tree decl) |
| { |
| const char *name = 0; |
| int reg_number; |
| tree id; |
| rtx x; |
| |
| /* Check that we are not being given an automatic variable. */ |
| gcc_assert (TREE_CODE (decl) != PARM_DECL |
| && TREE_CODE (decl) != RESULT_DECL); |
| |
| /* A weak alias has TREE_PUBLIC set but not the other bits. */ |
| gcc_assert (!VAR_P (decl) |
| || TREE_STATIC (decl) |
| || TREE_PUBLIC (decl) |
| || DECL_EXTERNAL (decl) |
| || DECL_REGISTER (decl)); |
| |
| /* And that we were not given a type or a label. */ |
| gcc_assert (TREE_CODE (decl) != TYPE_DECL |
| && TREE_CODE (decl) != LABEL_DECL); |
| |
| /* For a duplicate declaration, we can be called twice on the |
| same DECL node. Don't discard the RTL already made. */ |
| if (DECL_RTL_SET_P (decl)) |
| { |
| /* If the old RTL had the wrong mode, fix the mode. */ |
| x = DECL_RTL (decl); |
| if (GET_MODE (x) != DECL_MODE (decl)) |
| SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0)); |
| |
| if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl)) |
| return; |
| |
| /* ??? Another way to do this would be to maintain a hashed |
| table of such critters. Instead of adding stuff to a DECL |
| to give certain attributes to it, we could use an external |
| hash map from DECL to set of attributes. */ |
| |
| /* Let the target reassign the RTL if it wants. |
| This is necessary, for example, when one machine specific |
| decl attribute overrides another. */ |
| targetm.encode_section_info (decl, DECL_RTL (decl), false); |
| |
| /* If the symbol has a SYMBOL_REF_BLOCK field, update it based |
| on the new decl information. */ |
| if (MEM_P (x) |
| && GET_CODE (XEXP (x, 0)) == SYMBOL_REF |
| && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0))) |
| change_symbol_block (XEXP (x, 0), get_block_for_decl (decl)); |
| |
| return; |
| } |
| |
| /* If this variable belongs to the global constant pool, retrieve the |
| pre-computed RTL or recompute it in LTO mode. */ |
| if (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl)) |
| { |
| SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1)); |
| return; |
| } |
| |
| id = DECL_ASSEMBLER_NAME (decl); |
| name = IDENTIFIER_POINTER (id); |
| |
| if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL |
| && DECL_REGISTER (decl)) |
| { |
| error ("register name not specified for %q+D", decl); |
| } |
| else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl)) |
| { |
| const char *asmspec = name+1; |
| machine_mode mode = DECL_MODE (decl); |
| reg_number = decode_reg_name (asmspec); |
| /* First detect errors in declaring global registers. */ |
| if (reg_number == -1) |
| error ("register name not specified for %q+D", decl); |
| else if (reg_number < 0) |
| error ("invalid register name for %q+D", decl); |
| else if (mode == BLKmode) |
| error ("data type of %q+D isn%'t suitable for a register", |
| decl); |
| else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number)) |
| error ("the register specified for %q+D cannot be accessed" |
| " by the current target", decl); |
| else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number)) |
| error ("the register specified for %q+D is not general enough" |
| " to be used as a register variable", decl); |
| else if (!targetm.hard_regno_mode_ok (reg_number, mode)) |
| error ("register specified for %q+D isn%'t suitable for data type", |
| decl); |
| else if (reg_number != HARD_FRAME_POINTER_REGNUM |
| && (reg_number == FRAME_POINTER_REGNUM |
| #ifdef RETURN_ADDRESS_POINTER_REGNUM |
| || reg_number == RETURN_ADDRESS_POINTER_REGNUM |
| #endif |
| || reg_number == ARG_POINTER_REGNUM) |
| && eliminable_regno_p (reg_number)) |
| error ("register specified for %q+D is an internal GCC " |
| "implementation detail", decl); |
| /* Now handle properly declared static register variables. */ |
| else |
| { |
| int nregs; |
| |
| if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl)) |
| { |
| DECL_INITIAL (decl) = 0; |
| error ("global register variable has initial value"); |
| } |
| if (TREE_THIS_VOLATILE (decl)) |
| warning (OPT_Wvolatile_register_var, |
| "optimization may eliminate reads and/or " |
| "writes to register variables"); |
| |
| /* If the user specified one of the eliminables registers here, |
| e.g., FRAME_POINTER_REGNUM, we don't want to get this variable |
| confused with that register and be eliminated. This usage is |
| somewhat suspect... */ |
| |
| SET_DECL_RTL (decl, gen_raw_REG (mode, reg_number)); |
| ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number; |
| REG_USERVAR_P (DECL_RTL (decl)) = 1; |
| |
| if (TREE_STATIC (decl)) |
| { |
| /* Make this register global, so not usable for anything |
| else. */ |
| #ifdef ASM_DECLARE_REGISTER_GLOBAL |
| name = IDENTIFIER_POINTER (DECL_NAME (decl)); |
| ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name); |
| #endif |
| nregs = hard_regno_nregs (reg_number, mode); |
| while (nregs > 0) |
| globalize_reg (decl, reg_number + --nregs); |
| } |
| |
| /* As a register variable, it has no section. */ |
| return; |
| } |
| /* Avoid internal errors from invalid register |
| specifications. */ |
| SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE); |
| DECL_HARD_REGISTER (decl) = 0; |
| /* Also avoid SSA inconsistencies by pretending this is an external |
| decl now. */ |
| DECL_EXTERNAL (decl) = 1; |
| return; |
| } |
| /* Now handle ordinary static variables and functions (in memory). |
| Also handle vars declared register invalidly. */ |
| else if (name[0] == '*') |
| { |
| #ifdef REGISTER_PREFIX |
| if (strlen (REGISTER_PREFIX) != 0) |
| { |
| reg_number = decode_reg_name (name); |
| if (reg_number >= 0 || reg_number == -3) |
| error ("register name given for non-register variable %q+D", decl); |
| } |
| #endif |
| } |
| |
| /* Specifying a section attribute on a variable forces it into a |
| non-.bss section, and thus it cannot be common. */ |
| /* FIXME: In general this code should not be necessary because |
| visibility pass is doing the same work. But notice_global_symbol |
| is called early and it needs to make DECL_RTL to get the name. |
| we take care of recomputing the DECL_RTL after visibility is changed. */ |
| if (VAR_P (decl) |
| && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)) |
| && DECL_SECTION_NAME (decl) != NULL |
| && DECL_INITIAL (decl) == NULL_TREE |
| && DECL_COMMON (decl)) |
| DECL_COMMON (decl) = 0; |
| |
| /* Variables can't be both common and weak. */ |
| if (VAR_P (decl) && DECL_WEAK (decl)) |
| DECL_COMMON (decl) = 0; |
| |
| if (use_object_blocks_p () && use_blocks_for_decl_p (decl)) |
| x = create_block_symbol (name, get_block_for_decl (decl), -1); |
| else |
| { |
| machine_mode address_mode = Pmode; |
| if (TREE_TYPE (decl) != error_mark_node) |
| { |
| addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl)); |
| address_mode = targetm.addr_space.address_mode (as); |
| } |
| x = gen_rtx_SYMBOL_REF (address_mode, name); |
| } |
| SYMBOL_REF_WEAK (x) = DECL_WEAK (decl); |
| SET_SYMBOL_REF_DECL (x, decl); |
| |
| x = gen_rtx_MEM (DECL_MODE (decl), x); |
| if (TREE_CODE (decl) != FUNCTION_DECL) |
| set_mem_attributes (x, decl, 1); |
| SET_DECL_RTL (decl, x); |
| |
| /* Optionally set flags or add text to the name to record information |
| such as that it is a function name. |
| If the name is changed, the macro ASM_OUTPUT_LABELREF |
| will have to know how to strip this information. */ |
| targetm.encode_section_info (decl, DECL_RTL (decl), true); |
| } |
| |
| /* Like make_decl_rtl, but inhibit creation of new alias sets when |
| calling make_decl_rtl. Also, reset DECL_RTL before returning the |
| rtl. */ |
| |
| rtx |
| make_decl_rtl_for_debug (tree decl) |
| { |
| unsigned int save_aliasing_flag; |
| rtx rtl; |
| |
| if (DECL_RTL_SET_P (decl)) |
| return DECL_RTL (decl); |
| |
| /* Kludge alert! Somewhere down the call chain, make_decl_rtl will |
| call new_alias_set. If running with -fcompare-debug, sometimes |
| we do not want to create alias sets that will throw the alias |
| numbers off in the comparison dumps. So... clearing |
| flag_strict_aliasing will keep new_alias_set() from creating a |
| new set. */ |
| save_aliasing_flag = flag_strict_aliasing; |
| flag_strict_aliasing = 0; |
| |
| rtl = DECL_RTL (decl); |
| /* Reset DECL_RTL back, as various parts of the compiler expects |
| DECL_RTL set meaning it is actually going to be output. */ |
| SET_DECL_RTL (decl, NULL); |
| |
| flag_strict_aliasing = save_aliasing_flag; |
| return rtl; |
| } |
| |
| /* Output a string of literal assembler code |
| for an `asm' keyword used between functions. */ |
| |
| void |
| assemble_asm (tree string) |
| { |
| const char *p; |
| app_enable (); |
| |
| if (TREE_CODE (string) == ADDR_EXPR) |
| string = TREE_OPERAND (string, 0); |
| |
| p = TREE_STRING_POINTER (string); |
| fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p); |
| } |
| |
| /* Write the address of the entity given by SYMBOL to SEC. */ |
| void |
| assemble_addr_to_section (rtx symbol, section *sec) |
| { |
| switch_to_section (sec); |
| assemble_align (POINTER_SIZE); |
| assemble_integer (symbol, POINTER_SIZE_UNITS, POINTER_SIZE, 1); |
| } |
| |
| /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if |
| not) section for PRIORITY. */ |
| section * |
| get_cdtor_priority_section (int priority, bool constructor_p) |
| { |
| /* Buffer conservatively large enough for the full range of a 32-bit |
| int plus the text below. */ |
| char buf[18]; |
| |
| /* ??? This only works reliably with the GNU linker. */ |
| sprintf (buf, "%s.%.5u", |
| constructor_p ? ".ctors" : ".dtors", |
| /* Invert the numbering so the linker puts us in the proper |
| order; constructors are run from right to left, and the |
| linker sorts in increasing order. */ |
| MAX_INIT_PRIORITY - priority); |
| return get_section (buf, SECTION_WRITE, NULL); |
| } |
| |
| void |
| default_named_section_asm_out_destructor (rtx symbol, int priority) |
| { |
| section *sec; |
| |
| if (priority != DEFAULT_INIT_PRIORITY) |
| sec = get_cdtor_priority_section (priority, |
| /*constructor_p=*/false); |
| else |
| sec = get_section (".dtors", SECTION_WRITE, NULL); |
| |
| assemble_addr_to_section (symbol, sec); |
| } |
| |
| #ifdef DTORS_SECTION_ASM_OP |
| void |
| default_dtor_section_asm_out_destructor (rtx symbol, |
| int priority ATTRIBUTE_UNUSED) |
| { |
| assemble_addr_to_section (symbol, dtors_section); |
| } |
| #endif |
| |
| void |
| default_named_section_asm_out_constructor (rtx symbol, int priority) |
| { |
| section *sec; |
| |
| if (priority != DEFAULT_INIT_PRIORITY) |
| sec = get_cdtor_priority_section (priority, |
| /*constructor_p=*/true); |
| else |
| sec = get_section (".ctors", SECTION_WRITE, NULL); |
| |
| assemble_addr_to_section (symbol, sec); |
| } |
| |
| #ifdef CTORS_SECTION_ASM_OP |
| void |
| default_ctor_section_asm_out_constructor (rtx symbol, |
| int priority ATTRIBUTE_UNUSED) |
| { |
| assemble_addr_to_section (symbol, ctors_section); |
| } |
| #endif |
| |
| /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with |
| a nonzero value if the constant pool should be output before the |
| start of the function, or a zero value if the pool should output |
| after the end of the function. The default is to put it before the |
| start. */ |
| |
| #ifndef CONSTANT_POOL_BEFORE_FUNCTION |
| #define CONSTANT_POOL_BEFORE_FUNCTION 1 |
| #endif |
| |
| /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going |
| to be output to assembler. |
| Set first_global_object_name and weak_global_object_name as appropriate. */ |
| |
| void |
| notice_global_symbol (tree decl) |
| { |
| const char **t = &first_global_object_name; |
| |
| if (first_global_object_name |
| || !TREE_PUBLIC (decl) |
| || DECL_EXTERNAL (decl) |
| || !DECL_NAME (decl) |
| || (VAR_P (decl) && DECL_HARD_REGISTER (decl)) |
| || (TREE_CODE (decl) != FUNCTION_DECL |
| && (!VAR_P (decl) |
| || (DECL_COMMON (decl) |
| && (DECL_INITIAL (decl) == 0 |
| || DECL_INITIAL (decl) == error_mark_node))))) |
| return; |
| |
| /* We win when global object is found, but it is useful to know about weak |
| symbol as well so we can produce nicer unique names. */ |
| if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib) |
| t = &weak_global_object_name; |
| |
| if (!*t) |
| { |
| tree id = DECL_ASSEMBLER_NAME (decl); |
| ultimate_transparent_alias_target (&id); |
| *t = ggc_strdup (targetm.strip_name_encoding (IDENTIFIER_POINTER (id))); |
| } |
| } |
| |
| /* If not using flag_reorder_blocks_and_partition, decide early whether the |
| current function goes into the cold section, so that targets can use |
| current_function_section during RTL expansion. DECL describes the |
| function. */ |
| |
| void |
| decide_function_section (tree decl) |
| { |
| first_function_block_is_cold = false; |
| |
| if (DECL_SECTION_NAME (decl)) |
| { |
| struct cgraph_node *node = cgraph_node::get (current_function_decl); |
| /* Calls to function_section rely on first_function_block_is_cold |
| being accurate. */ |
| first_function_block_is_cold = (node |
| && node->frequency |
| == NODE_FREQUENCY_UNLIKELY_EXECUTED); |
| } |
| |
| in_cold_section_p = first_function_block_is_cold; |
| } |
| |
| /* Get the function's name, as described by its RTL. This may be |
| different from the DECL_NAME name used in the source file. */ |
| const char * |
| get_fnname_from_decl (tree decl) |
| { |
| rtx x = DECL_RTL (decl); |
| gcc_assert (MEM_P (x)); |
| x = XEXP (x, 0); |
| gcc_assert (GET_CODE (x) == SYMBOL_REF); |
| return XSTR (x, 0); |
| } |
| |
| /* Output assembler code for the constant pool of a function and associated |
| with defining the name of the function. DECL describes the function. |
| NAME is the function's name. For the constant pool, we use the current |
| constant pool data. */ |
| |
| void |
| assemble_start_function (tree decl, const char *fnname) |
| { |
| int align; |
| char tmp_label[100]; |
| bool hot_label_written = false; |
| |
| if (crtl->has_bb_partition) |
| { |
| ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno); |
| crtl->subsections.hot_section_label = ggc_strdup (tmp_label); |
| ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno); |
| crtl->subsections.cold_section_label = ggc_strdup (tmp_label); |
| ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno); |
| crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label); |
| ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno); |
| crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label); |
| const_labelno++; |
| cold_function_name = NULL_TREE; |
| } |
| else |
| { |
| crtl->subsections.hot_section_label = NULL; |
| crtl->subsections.cold_section_label = NULL; |
| crtl->subsections.hot_section_end_label = NULL; |
| crtl->subsections.cold_section_end_label = NULL; |
| } |
| |
| /* The following code does not need preprocessing in the assembler. */ |
| |
| app_disable (); |
| |
| if (CONSTANT_POOL_BEFORE_FUNCTION) |
| output_constant_pool (fnname, decl); |
| |
| align = symtab_node::get (decl)->definition_alignment (); |
| |
| /* Make sure the not and cold text (code) sections are properly |
| aligned. This is necessary here in the case where the function |
| has both hot and cold sections, because we don't want to re-set |
| the alignment when the section switch happens mid-function. */ |
| |
| if (crtl->has_bb_partition) |
| { |
| first_function_block_is_cold = false; |
| |
| switch_to_section (unlikely_text_section ()); |
| assemble_align (align); |
| ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label); |
| |
| /* When the function starts with a cold section, we need to explicitly |
| align the hot section and write out the hot section label. |
| But if the current function is a thunk, we do not have a CFG. */ |
| if (!cfun->is_thunk |
| && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION) |
| { |
| switch_to_section (text_section); |
| assemble_align (align); |
| ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label); |
| hot_label_written = true; |
| first_function_block_is_cold = true; |
| } |
| in_cold_section_p = first_function_block_is_cold; |
| } |
| |
| |
| /* Switch to the correct text section for the start of the function. */ |
| |
| switch_to_section (function_section (decl), decl); |
| if (crtl->has_bb_partition && !hot_label_written) |
| ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label); |
| |
| /* Tell assembler to move to target machine's alignment for functions. */ |
| align = floor_log2 (align / BITS_PER_UNIT); |
| if (align > 0) |
| { |
| ASM_OUTPUT_ALIGN (asm_out_file, align); |
| } |
| |
| /* Handle a user-specified function alignment. |
| Note that we still need to align to DECL_ALIGN, as above, |
| because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */ |
| if (! DECL_USER_ALIGN (decl) |
| && align_functions.levels[0].log > align |
| && optimize_function_for_speed_p (cfun)) |
| { |
| #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN |
| int align_log = align_functions.levels[0].log; |
| #endif |
| int max_skip = align_functions.levels[0].maxskip; |
| if (flag_limit_function_alignment && crtl->max_insn_address > 0 |
| && max_skip >= crtl->max_insn_address) |
| max_skip = crtl->max_insn_address - 1; |
| |
| #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN |
| ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file, align_log, max_skip); |
| if (max_skip == align_functions.levels[0].maxskip) |
| ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file, |
| align_functions.levels[1].log, |
| align_functions.levels[1].maxskip); |
| #else |
| ASM_OUTPUT_ALIGN (asm_out_file, align_functions.levels[0].log); |
| #endif |
| } |
| |
| #ifdef ASM_OUTPUT_FUNCTION_PREFIX |
| ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname); |
| #endif |
| |
| if (!DECL_IGNORED_P (decl)) |
| (*debug_hooks->begin_function) (decl); |
| |
| /* Make function name accessible from other files, if appropriate. */ |
| |
| if (TREE_PUBLIC (decl)) |
| { |
| notice_global_symbol (decl); |
| |
| globalize_decl (decl); |
| |
| maybe_assemble_visibility (decl); |
| } |
| |
| if (DECL_PRESERVE_P (decl)) |
| targetm.asm_out.mark_decl_preserved (fnname); |
| |
| unsigned short patch_area_size = crtl->patch_area_size; |
| unsigned short patch_area_entry = crtl->patch_area_entry; |
| |
| /* Emit the patching area before the entry label, if any. */ |
| if (patch_area_entry > 0) |
| targetm.asm_out.print_patchable_function_entry (asm_out_file, |
| patch_area_entry, true); |
| |
| /* Do any machine/system dependent processing of the function name. */ |
| #ifdef ASM_DECLARE_FUNCTION_NAME |
| ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl); |
| #else |
| /* Standard thing is just output label for the function. */ |
| ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl); |
| #endif /* ASM_DECLARE_FUNCTION_NAME */ |
| |
| /* And the area after the label. Record it if we haven't done so yet. */ |
| if (patch_area_size > patch_area_entry) |
| targetm.asm_out.print_patchable_function_entry (asm_out_file, |
| patch_area_size |
| - patch_area_entry, |
| patch_area_entry == 0); |
| |
| if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl))) |
| saw_no_split_stack = true; |
| } |
| |
| /* Output assembler code associated with defining the size of the |
| function. DECL describes the function. NAME is the function's name. */ |
| |
| void |
| assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED) |
| { |
| #ifdef ASM_DECLARE_FUNCTION_SIZE |
| /* We could have switched section in the middle of the function. */ |
| if (crtl->has_bb_partition) |
| switch_to_section (function_section (decl)); |
| ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl); |
| #endif |
| if (! CONSTANT_POOL_BEFORE_FUNCTION) |
| { |
| output_constant_pool (fnname, decl); |
| switch_to_section (function_section (decl)); /* need to switch back */ |
| } |
| /* Output labels for end of hot/cold text sections (to be used by |
| debug info.) */ |
| if (crtl->has_bb_partition) |
| { |
| section *save_text_section; |
| |
| save_text_section = in_section; |
| switch_to_section (unlikely_text_section ()); |
| #ifdef ASM_DECLARE_COLD_FUNCTION_SIZE |
| if (cold_function_name != NULL_TREE) |
| ASM_DECLARE_COLD_FUNCTION_SIZE (asm_out_file, |
| IDENTIFIER_POINTER (cold_function_name), |
| decl); |
| #endif |
| ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label); |
| if (first_function_block_is_cold) |
| switch_to_section (text_section); |
| else |
| switch_to_section (function_section (decl)); |
| ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label); |
| switch_to_section (save_text_section); |
| } |
| } |
| |
| /* Assemble code to leave SIZE bytes of zeros. */ |
| |
| void |
| assemble_zeros (unsigned HOST_WIDE_INT size) |
| { |
| /* Do no output if -fsyntax-only. */ |
| if (flag_syntax_only) |
| return; |
| |
| #ifdef ASM_NO_SKIP_IN_TEXT |
| /* The `space' pseudo in the text section outputs nop insns rather than 0s, |
| so we must output 0s explicitly in the text section. */ |
| if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0) |
| { |
| unsigned HOST_WIDE_INT i; |
| for (i = 0; i < size; i++) |
| assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1); |
| } |
| else |
| #endif |
| if (size > 0) |
| ASM_OUTPUT_SKIP (asm_out_file, size); |
| } |
| |
| /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */ |
| |
| void |
| assemble_align (unsigned int align) |
| { |
| if (align > BITS_PER_UNIT) |
| { |
| ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); |
| } |
| } |
| |
| /* Assemble a string constant with the specified C string as contents. */ |
| |
| void |
| assemble_string (const char *p, int size) |
| { |
| int pos = 0; |
| int maximum = 2000; |
| |
| /* If the string is very long, split it up. */ |
| |
| while (pos < size) |
| { |
| int thissize = size - pos; |
| if (thissize > maximum) |
| thissize = maximum; |
| |
| ASM_OUTPUT_ASCII (asm_out_file, p, thissize); |
| |
| pos += thissize; |
| p += thissize; |
| } |
| } |
| |
| |
| /* A noswitch_section_callback for lcomm_section. */ |
| |
| static bool |
| emit_local (tree decl ATTRIBUTE_UNUSED, |
| const char *name ATTRIBUTE_UNUSED, |
| unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED, |
| unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED) |
| { |
| #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL |
| unsigned int align = symtab_node::get (decl)->definition_alignment (); |
| ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name, |
| size, align); |
| return true; |
| #elif defined ASM_OUTPUT_ALIGNED_LOCAL |
| unsigned int align = symtab_node::get (decl)->definition_alignment (); |
| ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, align); |
| return true; |
| #else |
| ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded); |
| return false; |
| #endif |
| } |
| |
| /* A noswitch_section_callback for bss_noswitch_section. */ |
| |
| #if defined ASM_OUTPUT_ALIGNED_BSS |
| static bool |
| emit_bss (tree decl ATTRIBUTE_UNUSED, |
| const char *name ATTRIBUTE_UNUSED, |
| unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED, |
| unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED) |
| { |
| ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, |
| get_variable_align (decl)); |
| return true; |
| } |
| #endif |
| |
| /* A noswitch_section_callback for comm_section. */ |
| |
| static bool |
| emit_common (tree decl ATTRIBUTE_UNUSED, |
| const char *name ATTRIBUTE_UNUSED, |
| unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED, |
| unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED) |
| { |
| #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON |
| ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name, |
| size, get_variable_align (decl)); |
| return true; |
| #elif defined ASM_OUTPUT_ALIGNED_COMMON |
| ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, |
| get_variable_align (decl)); |
| return true; |
| #else |
| ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded); |
| return false; |
| #endif |
| } |
| |
| /* A noswitch_section_callback for tls_comm_section. */ |
| |
| static bool |
| emit_tls_common (tree decl ATTRIBUTE_UNUSED, |
| const char *name ATTRIBUTE_UNUSED, |
| unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED, |
| unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED) |
| { |
| #ifdef ASM_OUTPUT_TLS_COMMON |
| ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size); |
| return true; |
| #else |
| sorry ("thread-local COMMON data not implemented"); |
| return true; |
| #endif |
| } |
| |
| /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT. |
| NAME is the name of DECL's SYMBOL_REF. */ |
| |
| static void |
| assemble_noswitch_variable (tree decl, const char *name, section *sect, |
| unsigned int align) |
| { |
| unsigned HOST_WIDE_INT size, rounded; |
| |
| size = tree_to_uhwi (DECL_SIZE_UNIT (decl)); |
| rounded = size; |
| |
| if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl)) |
| size += asan_red_zone_size (size); |
| |
| /* Don't allocate zero bytes of common, |
| since that means "undefined external" in the linker. */ |
| if (size == 0) |
| rounded = 1; |
| |
| /* Round size up to multiple of BIGGEST_ALIGNMENT bits |
| so that each uninitialized object starts on such a boundary. */ |
| rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1; |
| rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT) |
| * (BIGGEST_ALIGNMENT / BITS_PER_UNIT)); |
| |
| if (!sect->noswitch.callback (decl, name, size, rounded) |
| && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded) |
| error ("requested alignment for %q+D is greater than " |
| "implemented alignment of %wu", decl, rounded); |
| } |
| |
| /* A subroutine of assemble_variable. Output the label and contents of |
| DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA |
| is as for assemble_variable. */ |
| |
| static void |
| assemble_variable_contents (tree decl, const char *name, |
| bool dont_output_data, bool merge_strings) |
| { |
| /* Do any machine/system dependent processing of the object. */ |
| #ifdef ASM_DECLARE_OBJECT_NAME |
| last_assemble_variable_decl = decl; |
| ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl); |
| #else |
| /* Standard thing is just output label for the object. */ |
| ASM_OUTPUT_LABEL (asm_out_file, name); |
| #endif /* ASM_DECLARE_OBJECT_NAME */ |
| |
| if (!dont_output_data) |
| { |
| /* Caller is supposed to use varpool_get_constructor when it wants |
| to output the body. */ |
| gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node); |
| if (DECL_INITIAL (decl) |
| && DECL_INITIAL (decl) != error_mark_node |
| && !initializer_zerop (DECL_INITIAL (decl))) |
| /* Output the actual data. */ |
| output_constant (DECL_INITIAL (decl), |
| tree_to_uhwi (DECL_SIZE_UNIT (decl)), |
| get_variable_align (decl), |
| false, merge_strings); |
| else |
| /* Leave space for it. */ |
| assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl))); |
| targetm.asm_out.decl_end (); |
| } |
| } |
| |
| /* Write out assembly for the variable DECL, which is not defined in |
| the current translation unit. */ |
| void |
| assemble_undefined_decl (tree decl) |
| { |
| const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0); |
| targetm.asm_out.assemble_undefined_decl (asm_out_file, name, decl); |
| } |
| |
| /* Assemble everything that is needed for a variable or function declaration. |
| Not used for automatic variables, and not used for function definitions. |
| Should not be called for variables of incomplete structure type. |
| |
| TOP_LEVEL is nonzero if this variable has file scope. |
| AT_END is nonzero if this is the special handling, at end of compilation, |
| to define things that have had only tentative definitions. |
| DONT_OUTPUT_DATA if nonzero means don't actually output the |
| initial value (that will be done by the caller). */ |
| |
| void |
| assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED, |
| int at_end ATTRIBUTE_UNUSED, int dont_output_data) |
| { |
| const char *name; |
| rtx decl_rtl, symbol; |
| section *sect; |
| unsigned int align; |
| bool asan_protected = false; |
| |
| /* This function is supposed to handle VARIABLES. Ensure we have one. */ |
| gcc_assert (VAR_P (decl)); |
| |
| /* Emulated TLS had better not get this far. */ |
| gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl)); |
| |
| last_assemble_variable_decl = 0; |
| |
| /* Normally no need to say anything here for external references, |
| since assemble_external is called by the language-specific code |
| when a declaration is first seen. */ |
| |
| if (DECL_EXTERNAL (decl)) |
| return; |
| |
| /* Do nothing for global register variables. */ |
| if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl))) |
| { |
| TREE_ASM_WRITTEN (decl) = 1; |
| return; |
| } |
| |
| /* If type was incomplete when the variable was declared, |
| see if it is complete now. */ |
| |
| if (DECL_SIZE (decl) == 0) |
| layout_decl (decl, 0); |
| |
| /* Still incomplete => don't allocate it; treat the tentative defn |
| (which is what it must have been) as an `extern' reference. */ |
| |
| if (!dont_output_data && DECL_SIZE (decl) == 0) |
| { |
| error ("storage size of %q+D isn%'t known", decl); |
| TREE_ASM_WRITTEN (decl) = 1; |
| return; |
| } |
| |
| /* The first declaration of a variable that comes through this function |
| decides whether it is global (in C, has external linkage) |
| or local (in C, has internal linkage). So do nothing more |
| if this function has already run. */ |
| |
| if (TREE_ASM_WRITTEN (decl)) |
| return; |
| |
| /* Make sure targetm.encode_section_info is invoked before we set |
| ASM_WRITTEN. */ |
| decl_rtl = DECL_RTL (decl); |
| |
| TREE_ASM_WRITTEN (decl) = 1; |
| |
| /* Do no output if -fsyntax-only. */ |
| if (flag_syntax_only) |
| return; |
| |
| if (! dont_output_data |
| && ! valid_constant_size_p (DECL_SIZE_UNIT (decl))) |
| { |
| error ("size of variable %q+D is too large", decl); |
| return; |
| } |
| |
| gcc_assert (MEM_P (decl_rtl)); |
| gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF); |
| symbol = XEXP (decl_rtl, 0); |
| |
| /* If this symbol belongs to the tree constant pool, output the constant |
| if it hasn't already been written. */ |
| if (TREE_CONSTANT_POOL_ADDRESS_P (symbol)) |
| { |
| tree decl = SYMBOL_REF_DECL (symbol); |
| if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl))) |
| output_constant_def_contents (symbol); |
| return; |
| } |
| |
| app_disable (); |
| |
| name = XSTR (symbol, 0); |
| if (TREE_PUBLIC (decl) && DECL_NAME (decl)) |
| notice_global_symbol (decl); |
| |
| /* Compute the alignment of this data. */ |
| |
| align_variable (decl, dont_output_data); |
| |
| if ((flag_sanitize & SANITIZE_ADDRESS) |
| && asan_protect_global (decl)) |
| { |
| asan_protected = true; |
| SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl), |
| ASAN_RED_ZONE_SIZE * BITS_PER_UNIT)); |
| } |
| |
| set_mem_align (decl_rtl, DECL_ALIGN (decl)); |
| |
| align = get_variable_align (decl); |
| |
| if (TREE_PUBLIC (decl)) |
| maybe_assemble_visibility (decl); |
| |
| if (DECL_PRESERVE_P (decl)) |
| targetm.asm_out.mark_decl_preserved (name); |
| |
| /* First make the assembler name(s) global if appropriate. */ |
| sect = get_variable_section (decl, false); |
| if (TREE_PUBLIC (decl) |
| && (sect->common.flags & SECTION_COMMON) == 0) |
| globalize_decl (decl); |
| |
| /* Output any data that we will need to use the address of. */ |
| if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node) |
| output_addressed_constants (DECL_INITIAL (decl), 0); |
| |
| /* dbxout.c needs to know this. */ |
| if (sect && (sect->common.flags & SECTION_CODE) != 0) |
| DECL_IN_TEXT_SECTION (decl) = 1; |
| |
| /* If the decl is part of an object_block, make sure that the decl |
| has been positioned within its block, but do not write out its |
| definition yet. output_object_blocks will do that later. */ |
| if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol)) |
| { |
| gcc_assert (!dont_output_data); |
| place_block_symbol (symbol); |
| } |
| else if (SECTION_STYLE (sect) == SECTION_NOSWITCH) |
| assemble_noswitch_variable (decl, name, sect, align); |
| else |
| { |
| /* Special-case handling of vtv comdat sections. */ |
| if (sect->named.name |
| && (strcmp (sect->named.name, ".vtable_map_vars") == 0)) |
| handle_vtv_comdat_section (sect, decl); |
| else |
| switch_to_section (sect, decl); |
| if (align > BITS_PER_UNIT) |
| ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); |
| assemble_variable_contents (decl, name, dont_output_data, |
| (sect->common.flags & SECTION_MERGE) |
| && (sect->common.flags & SECTION_STRINGS)); |
| if (asan_protected) |
| { |
| unsigned HOST_WIDE_INT int size |
| = tree_to_uhwi (DECL_SIZE_UNIT (decl)); |
| assemble_zeros (asan_red_zone_size (size)); |
| } |
| } |
| } |
| |
| |
| /* Given a function declaration (FN_DECL), this function assembles the |
| function into the .preinit_array section. */ |
| |
| void |
| assemble_vtv_preinit_initializer (tree fn_decl) |
| { |
| section *sect; |
| unsigned flags = SECTION_WRITE; |
| rtx symbol = XEXP (DECL_RTL (fn_decl), 0); |
| |
| flags |= SECTION_NOTYPE; |
| sect = get_section (".preinit_array", flags, fn_decl); |
| switch_to_section (sect); |
| assemble_addr_to_section (symbol, sect); |
| } |
| |
| /* Return 1 if type TYPE contains any pointers. */ |
| |
| static int |
| contains_pointers_p (tree type) |
| { |
| switch (TREE_CODE (type)) |
| { |
| case POINTER_TYPE: |
| case REFERENCE_TYPE: |
| /* I'm not sure whether OFFSET_TYPE needs this treatment, |
| so I'll play safe and return 1. */ |
| case OFFSET_TYPE: |
| return 1; |
| |
| case RECORD_TYPE: |
| case UNION_TYPE: |
| case QUAL_UNION_TYPE: |
| { |
| tree fields; |
| /* For a type that has fields, see if the fields have pointers. */ |
| for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields)) |
| if (TREE_CODE (fields) == FIELD_DECL |
| && contains_pointers_p (TREE_TYPE (fields))) |
| return 1; |
| return 0; |
| } |
| |
| case ARRAY_TYPE: |
| /* An array type contains pointers if its element type does. */ |
| return contains_pointers_p (TREE_TYPE (type)); |
| |
| default: |
| return 0; |
| } |
| } |
| |
| /* We delay assemble_external processing until |
| the compilation unit is finalized. This is the best we can do for |
| right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay |
| it all the way to final. See PR 17982 for further discussion. */ |
| static GTY(()) tree pending_assemble_externals; |
| |
| #ifdef ASM_OUTPUT_EXTERNAL |
| /* Some targets delay some output to final using TARGET_ASM_FILE_END. |
| As a result, assemble_external can be called after the list of externals |
| is processed and the pointer set destroyed. */ |
| static bool pending_assemble_externals_processed; |
| |
| /* Avoid O(external_decls**2) lookups in the pending_assemble_externals |
| TREE_LIST in assemble_external. */ |
| static hash_set<tree> *pending_assemble_externals_set; |
| |
| /* True if DECL is a function decl for which no out-of-line copy exists. |
| It is assumed that DECL's assembler name has been set. */ |
| |
| static bool |
| incorporeal_function_p (tree decl) |
| { |
| if (TREE_CODE (decl) == FUNCTION_DECL && fndecl_built_in_p (decl)) |
| { |
| const char *name; |
| |
| if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL |
| && ALLOCA_FUNCTION_CODE_P (DECL_FUNCTION_CODE (decl))) |
| return true; |
| |
| name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); |
| /* Atomic or sync builtins which have survived this far will be |
| resolved externally and therefore are not incorporeal. */ |
| if (strncmp (name, "__builtin_", 10) == 0) |
| return true; |
| } |
| return false; |
| } |
| |
| /* Actually do the tests to determine if this is necessary, and invoke |
| ASM_OUTPUT_EXTERNAL. */ |
| static void |
| assemble_external_real (tree decl) |
| { |
| rtx rtl = DECL_RTL (decl); |
| |
| if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF |
| && !SYMBOL_REF_USED (XEXP (rtl, 0)) |
| && !incorporeal_function_p (decl)) |
| { |
| /* Some systems do require some output. */ |
| SYMBOL_REF_USED (XEXP (rtl, 0)) = 1; |
| ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0)); |
| } |
| } |
| #endif |
| |
| void |
| process_pending_assemble_externals (void) |
| { |
| #ifdef ASM_OUTPUT_EXTERNAL |
| tree list; |
| for (list = pending_assemble_externals; list; list = TREE_CHAIN (list)) |
| assemble_external_real (TREE_VALUE (list)); |
| |
| pending_assemble_externals = 0; |
| pending_assemble_externals_processed = true; |
| delete pending_assemble_externals_set; |
| #endif |
| } |
| |
| /* This TREE_LIST contains any weak symbol declarations waiting |
| to be emitted. */ |
| static GTY(()) tree weak_decls; |
| |
| /* Output something to declare an external symbol to the assembler, |
| and qualifiers such as weakness. (Most assemblers don't need |
| extern declaration, so we normally output nothing.) Do nothing if |
| DECL is not external. */ |
| |
| void |
| assemble_external (tree decl ATTRIBUTE_UNUSED) |
| { |
| /* Make sure that the ASM_OUT_FILE is open. |
| If it's not, we should not be calling this function. */ |
| gcc_assert (asm_out_file); |
| |
| /* In a perfect world, the following condition would be true. |
| Sadly, the Go front end emit assembly *from the front end*, |
| bypassing the call graph. See PR52739. Fix before GCC 4.8. */ |
| #if 0 |
| /* This function should only be called if we are expanding, or have |
| expanded, to RTL. |
| Ideally, only final.c would be calling this function, but it is |
| not clear whether that would break things somehow. See PR 17982 |
| for further discussion. */ |
| gcc_assert (state == EXPANSION |
| || state == FINISHED); |
| #endif |
| |
| if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl)) |
| return; |
| |
| /* We want to output annotation for weak and external symbols at |
| very last to check if they are references or not. */ |
| |
| if (TARGET_SUPPORTS_WEAK |
| && DECL_WEAK (decl) |
| /* TREE_STATIC is a weird and abused creature which is not |
| generally the right test for whether an entity has been |
| locally emitted, inlined or otherwise not-really-extern, but |
| for declarations that can be weak, it happens to be |
| match. */ |
| && !TREE_STATIC (decl) |
| && lookup_attribute ("weak", DECL_ATTRIBUTES (decl)) |
| && value_member (decl, weak_decls) == NULL_TREE) |
| weak_decls = tree_cons (NULL, decl, weak_decls); |
| |
| #ifdef ASM_OUTPUT_EXTERNAL |
| if (pending_assemble_externals_processed) |
| { |
| assemble_external_real (decl); |
| return; |
| } |
| |
| if (! pending_assemble_externals_set->add (decl)) |
| pending_assemble_externals = tree_cons (NULL, decl, |
| pending_assemble_externals); |
| #endif |
| } |
| |
| /* Similar, for calling a library function FUN. */ |
| |
| void |
| assemble_external_libcall (rtx fun) |
| { |
| /* Declare library function name external when first used, if nec. */ |
| if (! SYMBOL_REF_USED (fun)) |
| { |
| SYMBOL_REF_USED (fun) = 1; |
| targetm.asm_out.external_libcall (fun); |
| } |
| } |
| |
| /* Assemble a label named NAME. */ |
| |
| void |
| assemble_label (FILE *file, const char *name) |
| { |
| ASM_OUTPUT_LABEL (file, name); |
| } |
| |
| /* Set the symbol_referenced flag for ID. */ |
| void |
| mark_referenced (tree id) |
| { |
| TREE_SYMBOL_REFERENCED (id) = 1; |
| } |
| |
| /* Set the symbol_referenced flag for DECL and notify callgraph. */ |
| void |
| mark_decl_referenced (tree decl) |
| { |
| if (TREE_CODE (decl) == FUNCTION_DECL) |
| { |
| /* Extern inline functions don't become needed when referenced. |
| If we know a method will be emitted in other TU and no new |
| functions can be marked reachable, just use the external |
| definition. */ |
| struct cgraph_node *node = cgraph_node::get_create (decl); |
| if (!DECL_EXTERNAL (decl) |
| && !node->definition) |
| node->mark_force_output (); |
| } |
| else if (VAR_P (decl)) |
| { |
| varpool_node *node = varpool_node::get_create (decl); |
| /* C++ frontend use mark_decl_references to force COMDAT variables |
| to be output that might appear dead otherwise. */ |
| node->force_output = true; |
| } |
| /* else do nothing - we can get various sorts of CST nodes here, |
| which do not need to be marked. */ |
| } |
| |
| |
| /* Output to FILE (an assembly file) a reference to NAME. If NAME |
| starts with a *, the rest of NAME is output verbatim. Otherwise |
| NAME is transformed in a target-specific way (usually by the |
| addition of an underscore). */ |
| |
| void |
| assemble_name_raw (FILE *file, const char *name) |
| { |
| if (name[0] == '*') |
| fputs (&name[1], file); |
| else |
| ASM_OUTPUT_LABELREF (file, name); |
| } |
| |
| /* Return NAME that should actually be emitted, looking through |
| transparent aliases. If NAME refers to an entity that is also |
| represented as a tree (like a function or variable), mark the entity |
| as referenced. */ |
| const char * |
| assemble_name_resolve (const char *name) |
| { |
| const char *real_name = targetm.strip_name_encoding (name); |
| tree id = maybe_get_identifier (real_name); |
| |
| if (id) |
| { |
| tree id_orig = id; |
| |
| mark_referenced (id); |
| ultimate_transparent_alias_target (&id); |
| if (id != id_orig) |
| name = IDENTIFIER_POINTER (id); |
| gcc_assert (! TREE_CHAIN (id)); |
| } |
| |
| return name; |
| } |
| |
| /* Like assemble_name_raw, but should be used when NAME might refer to |
| an entity that is also represented as a tree (like a function or |
| variable). If NAME does refer to such an entity, that entity will |
| be marked as referenced. */ |
| |
| void |
| assemble_name (FILE *file, const char *name) |
| { |
| assemble_name_raw (file, assemble_name_resolve (name)); |
| } |
| |
| /* Allocate SIZE bytes writable static space with a gensym name |
| and return an RTX to refer to its address. */ |
| |
| rtx |
| assemble_static_space (unsigned HOST_WIDE_INT size) |
| { |
| char name[17]; |
| const char *namestring; |
| rtx x; |
| |
| ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno); |
| ++const_labelno; |
| namestring = ggc_strdup (name); |
| |
| x = gen_rtx_SYMBOL_REF (Pmode, namestring); |
| SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL; |
| |
| #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL |
| ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size, |
| BIGGEST_ALIGNMENT); |
| #else |
| #ifdef ASM_OUTPUT_ALIGNED_LOCAL |
| ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT); |
| #else |
| { |
| /* Round size up to multiple of BIGGEST_ALIGNMENT bits |
| so that each uninitialized object starts on such a boundary. */ |
| /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */ |
| unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED |
| = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1) |
| / (BIGGEST_ALIGNMENT / BITS_PER_UNIT) |
| * (BIGGEST_ALIGNMENT / BITS_PER_UNIT)); |
| ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded); |
| } |
| #endif |
| #endif |
| return x; |
| } |
| |
| /* Assemble the static constant template for function entry trampolines. |
| This is done at most once per compilation. |
| Returns an RTX for the address of the template. */ |
| |
| static GTY(()) rtx initial_trampoline; |
| |
| rtx |
| assemble_trampoline_template (void) |
| { |
| char label[256]; |
| const char *name; |
| int align; |
| rtx symbol; |
| |
| gcc_assert (targetm.asm_out.trampoline_template != NULL); |
| |
| if (initial_trampoline) |
| return initial_trampoline; |
| |
| /* By default, put trampoline templates in read-only data section. */ |
| |
| #ifdef TRAMPOLINE_SECTION |
| switch_to_section (TRAMPOLINE_SECTION); |
| #else |
| switch_to_section (readonly_data_section); |
| #endif |
| |
| /* Write the assembler code to define one. */ |
| align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT); |
| if (align > 0) |
| ASM_OUTPUT_ALIGN (asm_out_file, align); |
| |
| targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0); |
| targetm.asm_out.trampoline_template (asm_out_file); |
| |
| /* Record the rtl to refer to it. */ |
| ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0); |
| name = ggc_strdup (label); |
| symbol = gen_rtx_SYMBOL_REF (Pmode, name); |
| SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL; |
| |
| initial_trampoline = gen_const_mem (BLKmode, symbol); |
| set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT); |
| set_mem_size (initial_trampoline, TRAMPOLINE_SIZE); |
| |
| return initial_trampoline; |
| } |
| |
| /* A and B are either alignments or offsets. Return the minimum alignment |
| that may be assumed after adding the two together. */ |
| |
| static inline unsigned |
| min_align (unsigned int a, unsigned int b) |
| { |
| return least_bit_hwi (a | b); |
| } |
| |
| /* Return the assembler directive for creating a given kind of integer |
| object. SIZE is the number of bytes in the object and ALIGNED_P |
| indicates whether it is known to be aligned. Return NULL if the |
| assembly dialect has no such directive. |
| |
| The returned string should be printed at the start of a new line and |
| be followed immediately by the object's initial value. */ |
| |
| const char * |
| integer_asm_op (int size, int aligned_p) |
| { |
| struct asm_int_op *ops; |
| |
| if (aligned_p) |
| ops = &targetm.asm_out.aligned_op; |
| else |
| ops = &targetm.asm_out.unaligned_op; |
| |
| switch (size) |
| { |
| case 1: |
| return targetm.asm_out.byte_op; |
| case 2: |
| return ops->hi; |
| case 3: |
| return ops->psi; |
| case 4: |
| return ops->si; |
| case 5: |
| case 6: |
| case 7: |
| return ops->pdi; |
| case 8: |
| return ops->di; |
| case 9: |
| case 10: |
| case 11: |
| case 12: |
| case 13: |
| case 14: |
| case 15: |
| return ops->pti; |
| case 16: |
| return ops->ti; |
| default: |
| return NULL; |
| } |
| } |
| |
| /* Use directive OP to assemble an integer object X. Print OP at the |
| start of the line, followed immediately by the value of X. */ |
| |
| void |
| assemble_integer_with_op (const char *op, rtx x) |
| { |
| fputs (op, asm_out_file); |
| output_addr_const (asm_out_file, x); |
| fputc ('\n', asm_out_file); |
| } |
| |
| /* The default implementation of the asm_out.integer target hook. */ |
| |
| bool |
| default_assemble_integer (rtx x ATTRIBUTE_UNUSED, |
| unsigned int size ATTRIBUTE_UNUSED, |
| int aligned_p ATTRIBUTE_UNUSED) |
| { |
| const char *op = integer_asm_op (size, aligned_p); |
| /* Avoid GAS bugs for large values. Specifically negative values whose |
| absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */ |
| if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS) |
| return false; |
| return op && (assemble_integer_with_op (op, x), true); |
| } |
| |
| /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is |
| the alignment of the integer in bits. Return 1 if we were able to output |
| the constant, otherwise 0. We must be able to output the constant, |
| if FORCE is nonzero. */ |
| |
| bool |
| assemble_integer (rtx x, unsigned int size, unsigned int align, int force) |
| { |
| int aligned_p; |
| |
| aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT)); |
| |
| /* See if the target hook can handle this kind of object. */ |
| if (targetm.asm_out.integer (x, size, aligned_p)) |
| return true; |
| |
| /* If the object is a multi-byte one, try splitting it up. Split |
| it into words it if is multi-word, otherwise split it into bytes. */ |
| if (size > 1) |
| { |
| machine_mode omode, imode; |
| unsigned int subalign; |
| unsigned int subsize, i; |
| enum mode_class mclass; |
| |
| subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1; |
| subalign = MIN (align, subsize * BITS_PER_UNIT); |
| if (GET_CODE (x) == CONST_FIXED) |
| mclass = GET_MODE_CLASS (GET_MODE (x)); |
| else |
| mclass = MODE_INT; |
| |
| omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0).require (); |
| imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0).require (); |
| |
| for (i = 0; i < size; i += subsize) |
| { |
| rtx partial = simplify_subreg (omode, x, imode, i); |
| if (!partial || !assemble_integer (partial, subsize, subalign, 0)) |
| break; |
| } |
| if (i == size) |
| return true; |
| |
| /* If we've printed some of it, but not all of it, there's no going |
| back now. */ |
| gcc_assert (!i); |
| } |
| |
| gcc_assert (!force); |
| |
| return false; |
| } |
| |
| /* Assemble the floating-point constant D into an object of size MODE. ALIGN |
| is the alignment of the constant in bits. If REVERSE is true, D is output |
| in reverse storage order. */ |
| |
| void |
| assemble_real (REAL_VALUE_TYPE d, scalar_float_mode mode, unsigned int align, |
| bool reverse) |
| { |
| long data[4] = {0, 0, 0, 0}; |
| int bitsize, nelts, nunits, units_per; |
| rtx elt; |
| |
| /* This is hairy. We have a quantity of known size. real_to_target |
| will put it into an array of *host* longs, 32 bits per element |
| (even if long is more than 32 bits). We need to determine the |
| number of array elements that are occupied (nelts) and the number |
| of *target* min-addressable units that will be occupied in the |
| object file (nunits). We cannot assume that 32 divides the |
| mode's bitsize (size * BITS_PER_UNIT) evenly. |
| |
| size * BITS_PER_UNIT is used here to make sure that padding bits |
| (which might appear at either end of the value; real_to_target |
| will include the padding bits in its output array) are included. */ |
| |
| nunits = GET_MODE_SIZE (mode); |
| bitsize = nunits * BITS_PER_UNIT; |
| nelts = CEIL (bitsize, 32); |
| units_per = 32 / BITS_PER_UNIT; |
| |
| real_to_target (data, &d, mode); |
| |
| /* Put out the first word with the specified alignment. */ |
| unsigned int chunk_nunits = MIN (nunits, units_per); |
| if (reverse) |
| elt = flip_storage_order (SImode, gen_int_mode (data[nelts - 1], SImode)); |
| else |
| elt = GEN_INT (sext_hwi (data[0], chunk_nunits * BITS_PER_UNIT)); |
| assemble_integer (elt, chunk_nunits, align, 1); |
| nunits -= chunk_nunits; |
| |
| /* Subsequent words need only 32-bit alignment. */ |
| align = min_align (align, 32); |
| |
| for (int i = 1; i < nelts; i++) |
| { |
| chunk_nunits = MIN (nunits, units_per); |
| if (reverse) |
| elt = flip_storage_order (SImode, |
| gen_int_mode (data[nelts - 1 - i], SImode)); |
| else |
| elt = GEN_INT (sext_hwi (data[i], chunk_nunits * BITS_PER_UNIT)); |
| assemble_integer (elt, chunk_nunits, align, 1); |
| nunits -= chunk_nunits; |
| } |
| } |
| |
| /* Given an expression EXP with a constant value, |
| reduce it to the sum of an assembler symbol and an integer. |
| Store them both in the structure *VALUE. |
| EXP must be reducible. */ |
| |
| class addr_const { |
| public: |
| rtx base; |
| poly_int64 offset; |
| }; |
| |
| static void |
| decode_addr_const (tree exp, class addr_const *value) |
| { |
| tree target = TREE_OPERAND (exp, 0); |
| poly_int64 offset = 0; |
| rtx x; |
| |
| while (1) |
| { |
| poly_int64 bytepos; |
| if (TREE_CODE (target) == COMPONENT_REF |
| && poly_int_tree_p (byte_position (TREE_OPERAND (target, 1)), |
| &bytepos)) |
| { |
| offset += bytepos; |
| target = TREE_OPERAND (target, 0); |
| } |
| else if (TREE_CODE (target) == ARRAY_REF |
| || TREE_CODE (target) == ARRAY_RANGE_REF) |
| { |
| /* Truncate big offset. */ |
| offset |
| += (TREE_INT_CST_LOW (TYPE_SIZE_UNIT (TREE_TYPE (target))) |
| * wi::to_poly_widest (TREE_OPERAND (target, 1)).force_shwi ()); |
| target = TREE_OPERAND (target, 0); |
| } |
| else if (TREE_CODE (target) == MEM_REF |
| && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR) |
| { |
| offset += mem_ref_offset (target).force_shwi (); |
| target = TREE_OPERAND (TREE_OPERAND (target, 0), 0); |
| } |
| else if (TREE_CODE (target) == INDIRECT_REF |
| && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR |
| && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0)) |
| == ADDR_EXPR) |
| target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0); |
| else |
| break; |
| } |
| |
| switch (TREE_CODE (target)) |
| { |
| case VAR_DECL: |
| case FUNCTION_DECL: |
| x = DECL_RTL (target); |
| break; |
| |
| case LABEL_DECL: |
| x = gen_rtx_MEM (FUNCTION_MODE, |
| gen_rtx_LABEL_REF (Pmode, force_label_rtx (target))); |
| break; |
| |
| case REAL_CST: |
| case FIXED_CST: |
| case STRING_CST: |
| case COMPLEX_CST: |
| case CONSTRUCTOR: |
| case INTEGER_CST: |
| x = lookup_constant_def (target); |
| /* Should have been added by output_addressed_constants. */ |
| gcc_assert (x); |
| break; |
| |
| case INDIRECT_REF: |
| /* This deals with absolute addresses. */ |
| offset += tree_to_shwi (TREE_OPERAND (target, 0)); |
| x = gen_rtx_MEM (QImode, |
| gen_rtx_SYMBOL_REF (Pmode, "origin of addresses")); |
| break; |
| |
| case COMPOUND_LITERAL_EXPR: |
| gcc_assert (COMPOUND_LITERAL_EXPR_DECL (target)); |
| x = DECL_RTL (COMPOUND_LITERAL_EXPR_DECL (target)); |
| break; |
| |
| default: |
| gcc_unreachable (); |
| } |
| |
| gcc_assert (MEM_P (x)); |
| x = XEXP (x, 0); |
| |
| value->base = x; |
| value->offset = offset; |
| } |
| |
| static GTY(()) hash_table<tree_descriptor_hasher> *const_desc_htab; |
| |
| static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int); |
| |
| /* Constant pool accessor function. */ |
| |
| hash_table<tree_descriptor_hasher> * |
| constant_pool_htab (void) |
| { |
| return const_desc_htab; |
| } |
| |
| /* Compute a hash code for a constant expression. */ |
| |
| hashval_t |
| tree_descriptor_hasher::hash (constant_descriptor_tree *ptr) |
| { |
| return ptr->hash; |
| } |
| |
| static hashval_t |
| const_hash_1 (const tree exp) |
| { |
| const char *p; |
| hashval_t hi; |
| int len, i; |
| enum tree_code code = TREE_CODE (exp); |
| |
| /* Either set P and LEN to the address and len of something to hash and |
| exit the switch or return a value. */ |
| |
| switch (code) |
| { |
| case INTEGER_CST: |
| p = (char *) &TREE_INT_CST_ELT (exp, 0); |
| len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT); |
| break; |
| |
| case REAL_CST: |
| return real_hash (TREE_REAL_CST_PTR (exp)); |
| |
| case FIXED_CST: |
| return fixed_hash (TREE_FIXED_CST_PTR (exp)); |
| |
| case STRING_CST: |
| p = TREE_STRING_POINTER (exp); |
| len = TREE_STRING_LENGTH (exp); |
| break; |
| |
| case COMPLEX_CST: |
| return (const_hash_1 (TREE_REALPART (exp)) * 5 |
| + const_hash_1 (TREE_IMAGPART (exp))); |
| |
| case VECTOR_CST: |
| { |
| hi = 7 + VECTOR_CST_NPATTERNS (exp); |
| hi = hi * 563 + VECTOR_CST_NELTS_PER_PATTERN (exp); |
| unsigned int count = vector_cst_encoded_nelts (exp); |
| for (unsigned int i = 0; i < count; ++i) |
| hi = hi * 563 + const_hash_1 (VECTOR_CST_ENCODED_ELT (exp, i)); |
| return hi; |
| } |
| |
| case CONSTRUCTOR: |
| { |
| unsigned HOST_WIDE_INT idx; |
| tree value; |
| |
| hi = 5 + int_size_in_bytes (TREE_TYPE (exp)); |
| |
| FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value) |
| if (value) |
| hi = hi * 603 + const_hash_1 (value); |
| |
| return hi; |
| } |
| |
| case ADDR_EXPR: |
| if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0))) |
| return const_hash_1 (TREE_OPERAND (exp, 0)); |
| |
| /* Fallthru. */ |
| case FDESC_EXPR: |
| { |
| class addr_const value; |
| |
| decode_addr_const (exp, &value); |
| switch (GET_CODE (value.base)) |
| { |
| case SYMBOL_REF: |
| /* Don't hash the address of the SYMBOL_REF; |
| only use the offset and the symbol name. */ |
| hi = value.offset.coeffs[0]; |
| p = XSTR (value.base, 0); |
| for (i = 0; p[i] != 0; i++) |
| hi = ((hi * 613) + (unsigned) (p[i])); |
| break; |
| |
| case LABEL_REF: |
| hi = (value.offset.coeffs[0] |
| + CODE_LABEL_NUMBER (label_ref_label (value.base)) * 13); |
| break; |
| |
| default: |
| gcc_unreachable (); |
| } |
| } |
| return hi; |
| |
| case PLUS_EXPR: |
| case POINTER_PLUS_EXPR: |
| case MINUS_EXPR: |
| return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9 |
| + const_hash_1 (TREE_OPERAND (exp, 1))); |
| |
| CASE_CONVERT: |
| return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2; |
| |
| default: |
| /* A language specific constant. Just hash the code. */ |
| return code; |
| } |
| |
| /* Compute hashing function. */ |
| hi = len; |
| for (i = 0; i < len; i++) |
| hi = ((hi * 613) + (unsigned) (p[i])); |
| |
| return hi; |
| } |
| |
| /* Wrapper of compare_constant, for the htab interface. */ |
| bool |
| tree_descriptor_hasher::equal (constant_descriptor_tree *c1, |
| constant_descriptor_tree *c2) |
| { |
| if (c1->hash != c2->hash) |
| return 0; |
| return compare_constant (c1->value, c2->value); |
| } |
| |
| /* Compare t1 and t2, and return 1 only if they are known to result in |
| the same bit pattern on output. */ |
| |
| static int |
| compare_constant (const tree t1, const tree t2) |
| { |
| enum tree_code typecode; |
| |
| if (t1 == NULL_TREE) |
| return t2 == NULL_TREE; |
| if (t2 == NULL_TREE) |
| return 0; |
| |
| if (TREE_CODE (t1) != TREE_CODE (t2)) |
| return 0; |
| |
| switch (TREE_CODE (t1)) |
| { |
| case INTEGER_CST: |
| /* Integer constants are the same only if the same width of type. */ |
| if (TYPE_PRECISION (TREE_TYPE (t1)) !=
|