| /* Functions for generic Darwin as target machine for GNU C compiler. |
| Copyright (C) 1989-2021 Free Software Foundation, Inc. |
| Contributed by Apple Computer 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/>. */ |
| |
| #include "config.h" |
| #include "system.h" |
| #include "coretypes.h" |
| #include "backend.h" |
| #include "target.h" |
| #include "rtl.h" |
| #include "tree.h" |
| #include "gimple.h" |
| #include "cfghooks.h" |
| #include "df.h" |
| #include "memmodel.h" |
| #include "tm_p.h" |
| #include "stringpool.h" |
| #include "attribs.h" |
| #include "insn-config.h" |
| #include "emit-rtl.h" |
| #include "cgraph.h" |
| #include "lto-streamer.h" |
| #include "output.h" |
| #include "varasm.h" |
| #include "stor-layout.h" |
| #include "explow.h" |
| #include "expr.h" |
| #include "langhooks.h" |
| #include "targhooks.h" |
| #include "toplev.h" |
| #include "lto-section-names.h" |
| #include "intl.h" |
| #include "optabs.h" |
| #include "flags.h" |
| |
| /* Fix and Continue. |
| |
| NOTES: |
| 1) this facility requires suitable support from a modified version |
| of GDB, which is not provided on any system after MacOS 10.7/Darwin11. |
| 2) There is no support for this in any X86 version of the FSF compiler. |
| |
| Fix and continue was used on some earlier MacOS systems for rapid turn |
| around debugging. When code is compiled with the -mfix-and-continue |
| flag, two changes are made to the generated code that allow the system |
| to do things that it would normally not be able to do easily. These |
| changes allow gdb to load in recompilation of a translation unit that |
| has been changed into a running program and replace existing functions |
| and methods of that translation unit with versions of those functions |
| and methods from the newly compiled translation unit. The new functions |
| access the existing static symbols from the old translation unit, if the |
| symbol existed in the unit to be replaced, and from the new translation |
| unit, otherwise. |
| |
| The changes are to insert 5 nops at the beginning of all functions |
| and to use indirection to get at static symbols. The 5 nops |
| are required by consumers of the generated code. Currently, gdb |
| uses this to patch in a jump to the overriding function, this |
| allows all uses of the old name to forward to the replacement, |
| including existing function pointers and virtual methods. See |
| rs6000_emit_prologue for the code that handles the nop insertions. |
| |
| The added indirection allows gdb to redirect accesses to static |
| symbols from the newly loaded translation unit to the existing |
| symbol, if any. @code{static} symbols are special and are handled by |
| setting the second word in the .non_lazy_symbol_pointer data |
| structure to symbol. See indirect_data for the code that handles |
| the extra indirection, and machopic_output_indirection and its use |
| of MACHO_SYMBOL_FLAG_STATIC for the code that handles @code{static} |
| symbol indirection. */ |
| |
| typedef struct GTY(()) cdtor_record { |
| rtx symbol; |
| int priority; /* [con/de]structor priority */ |
| int position; /* original position */ |
| } cdtor_record; |
| |
| static GTY(()) vec<cdtor_record, va_gc> *ctors = NULL; |
| static GTY(()) vec<cdtor_record, va_gc> *dtors = NULL; |
| |
| /* A flag to determine whether we are running c++ or obj-c++. This has to be |
| settable from non-c-family contexts too (i.e. we can't use the c_dialect_ |
| functions). */ |
| int darwin_running_cxx; |
| |
| /* Some code-gen now depends on OS major version numbers (at least). */ |
| int generating_for_darwin_version ; |
| |
| /* For older linkers we need to emit special sections (marked 'coalesced') for |
| for weak or single-definition items. */ |
| static bool ld_uses_coal_sects = false; |
| |
| /* Very old (ld_classic) linkers need a symbol to mark the start of |
| each FDE. */ |
| static bool ld_needs_eh_markers = false; |
| |
| /* Emit a section-start symbol for mod init and term sections. */ |
| static bool ld_init_term_start_labels = false; |
| |
| /* Section names. */ |
| section * darwin_sections[NUM_DARWIN_SECTIONS]; |
| |
| /* While we transition to using in-tests instead of ifdef'd code. */ |
| #if !HAVE_lo_sum |
| #define gen_macho_high(m,a,b) (a) |
| #define gen_macho_low(m,a,b,c) (a) |
| #endif |
| |
| /* True if we're setting __attribute__ ((ms_struct)). */ |
| int darwin_ms_struct = false; |
| |
| /* Earlier versions of Darwin as do not recognize an alignment field in |
| .comm directives, this should be set for versions that allow it. */ |
| int emit_aligned_common = false; |
| |
| /* A get_unnamed_section callback used to switch to an ObjC section. |
| DIRECTIVE is as for output_section_asm_op. */ |
| |
| static void |
| output_objc_section_asm_op (const void *directive) |
| { |
| static bool been_here = false; |
| |
| /* The NeXT ObjC Runtime requires these sections to be present and in |
| order in the object. The code below implements this by emitting |
| a section header for each ObjC section the first time that an ObjC |
| section is requested. */ |
| if (darwin_symbol_stubs && ! been_here) |
| { |
| section *saved_in_section = in_section; |
| static const enum darwin_section_enum tomark[] = |
| { |
| /* written, cold -> hot */ |
| objc_cat_cls_meth_section, |
| objc_cat_inst_meth_section, |
| objc_string_object_section, |
| objc_constant_string_object_section, |
| objc_selector_refs_section, |
| objc_selector_fixup_section, |
| objc_cls_refs_section, |
| objc_class_section, |
| objc_meta_class_section, |
| /* shared, hot -> cold */ |
| objc_cls_meth_section, |
| objc_inst_meth_section, |
| objc_protocol_section, |
| objc_class_names_section, |
| objc_meth_var_types_section, |
| objc_meth_var_names_section, |
| objc_category_section, |
| objc_class_vars_section, |
| objc_instance_vars_section, |
| objc_module_info_section, |
| objc_symbols_section, |
| }; |
| /* ABI=1 */ |
| static const enum darwin_section_enum tomarkv1[] = |
| { |
| objc1_protocol_ext_section, |
| objc1_class_ext_section, |
| objc1_prop_list_section |
| } ; |
| /* ABI=2 */ |
| static const enum darwin_section_enum tomarkv2[] = |
| { |
| objc2_method_names_section, |
| objc2_message_refs_section, |
| objc2_selector_refs_section, |
| objc2_ivar_section, |
| objc2_classdefs_section, |
| objc2_metadata_section, |
| objc2_classrefs_section, |
| objc2_class_names_section, |
| objc2_classlist_section, |
| objc2_categorylist_section, |
| objc2_nonlazy_class_section, |
| objc2_nonlazy_category_section, |
| objc2_protocollist_section, |
| objc2_protocolrefs_section, |
| objc2_super_classrefs_section, |
| objc2_constant_string_object_section, |
| objc2_image_info_section, |
| } ; |
| size_t i; |
| |
| been_here = true; |
| if (flag_objc_abi < 2) |
| { |
| for (i = 0; i < ARRAY_SIZE (tomark); i++) |
| switch_to_section (darwin_sections[tomark[i]]); |
| if (flag_objc_abi == 1) |
| for (i = 0; i < ARRAY_SIZE (tomarkv1); i++) |
| switch_to_section (darwin_sections[tomarkv1[i]]); |
| } |
| else |
| for (i = 0; i < ARRAY_SIZE (tomarkv2); i++) |
| switch_to_section (darwin_sections[tomarkv2[i]]); |
| /* Make sure we don't get varasm.c out of sync with us. */ |
| switch_to_section (saved_in_section); |
| } |
| output_section_asm_op (directive); |
| } |
| |
| |
| /* Private flag applied to disable section-anchors in a particular section. */ |
| #define SECTION_NO_ANCHOR SECTION_MACH_DEP |
| |
| |
| /* Implement TARGET_ASM_INIT_SECTIONS. */ |
| |
| void |
| darwin_init_sections (void) |
| { |
| #define DEF_SECTION(NAME, FLAGS, DIRECTIVE, OBJC) \ |
| darwin_sections[NAME] = \ |
| get_unnamed_section (FLAGS, (OBJC \ |
| ? output_objc_section_asm_op \ |
| : output_section_asm_op), \ |
| "\t" DIRECTIVE); |
| #include "config/darwin-sections.def" |
| #undef DEF_SECTION |
| |
| readonly_data_section = darwin_sections[const_section]; |
| exception_section = darwin_sections[darwin_exception_section]; |
| eh_frame_section = darwin_sections[darwin_eh_frame_section]; |
| |
| /* If our linker is new enough to coalesce weak symbols, then we |
| can just put picbase_thunks into the text section. */ |
| if (! ld_uses_coal_sects ) |
| darwin_sections[picbase_thunk_section] = text_section; |
| } |
| |
| int |
| name_needs_quotes (const char *name) |
| { |
| int c; |
| while ((c = *name++) != '\0') |
| if (! ISIDNUM (c) |
| && c != '.' && c != '$' && c != '_' ) |
| return 1; |
| return 0; |
| } |
| |
| /* Return true if SYM_REF can be used without an indirection. */ |
| int |
| machopic_symbol_defined_p (rtx sym_ref) |
| { |
| if (MACHO_SYMBOL_DEFINED_P (sym_ref)) |
| return true; |
| |
| /* If a symbol references local and is not an extern to this |
| file, then the symbol might be able to declared as defined. */ |
| if (SYMBOL_REF_LOCAL_P (sym_ref) && ! SYMBOL_REF_EXTERNAL_P (sym_ref)) |
| { |
| /* If the symbol references a variable and the variable is a |
| common symbol, then this symbol is not defined. */ |
| if (MACHO_SYMBOL_VARIABLE_P (sym_ref)) |
| { |
| tree decl = SYMBOL_REF_DECL (sym_ref); |
| if (!decl) |
| return true; |
| if (DECL_COMMON (decl)) |
| return false; |
| } |
| return true; |
| } |
| return false; |
| } |
| |
| /* This module assumes that (const (symbol_ref "foo")) is a legal pic |
| reference, which will not be changed. */ |
| |
| enum machopic_addr_class |
| machopic_classify_symbol (rtx sym_ref) |
| { |
| bool function_p; |
| |
| function_p = SYMBOL_REF_FUNCTION_P (sym_ref); |
| if (machopic_symbol_defined_p (sym_ref)) |
| return (function_p |
| ? MACHOPIC_DEFINED_FUNCTION : MACHOPIC_DEFINED_DATA); |
| else |
| return (function_p |
| ? MACHOPIC_UNDEFINED_FUNCTION : MACHOPIC_UNDEFINED_DATA); |
| } |
| |
| #ifndef TARGET_FIX_AND_CONTINUE |
| #define TARGET_FIX_AND_CONTINUE 0 |
| #endif |
| |
| /* Indicate when fix-and-continue style code generation is being used |
| and when a reference to data should be indirected so that it can be |
| rebound in a new translation unit to reference the original instance |
| of that data. Symbol names that are for code generation local to |
| the translation unit are bound to the new translation unit; |
| currently this means symbols that begin with L or _OBJC_; |
| otherwise, we indicate that an indirect reference should be made to |
| permit the runtime to rebind new instances of the translation unit |
| to the original instance of the data. */ |
| |
| static int |
| indirect_data (rtx sym_ref) |
| { |
| int lprefix; |
| const char *name; |
| |
| /* If we aren't generating fix-and-continue code, don't do anything |
| special. */ |
| if (TARGET_FIX_AND_CONTINUE == 0) |
| return 0; |
| |
| /* Otherwise, all symbol except symbols that begin with L or _OBJC_ |
| are indirected. Symbols that begin with L and _OBJC_ are always |
| bound to the current translation unit as they are used for |
| generated local data of the translation unit. */ |
| |
| name = XSTR (sym_ref, 0); |
| |
| lprefix = (((name[0] == '*' || name[0] == '&') |
| && (name[1] == 'L' || (name[1] == '"' && name[2] == 'L'))) |
| || (startswith (name, "_OBJC_"))); |
| |
| return ! lprefix; |
| } |
| |
| static int |
| machopic_data_defined_p (rtx sym_ref) |
| { |
| if (indirect_data (sym_ref)) |
| return 0; |
| |
| switch (machopic_classify_symbol (sym_ref)) |
| { |
| case MACHOPIC_DEFINED_DATA: |
| case MACHOPIC_DEFINED_FUNCTION: |
| return 1; |
| default: |
| return 0; |
| } |
| } |
| |
| void |
| machopic_define_symbol (rtx mem) |
| { |
| rtx sym_ref; |
| |
| gcc_assert (GET_CODE (mem) == MEM); |
| sym_ref = XEXP (mem, 0); |
| SYMBOL_REF_FLAGS (sym_ref) |= MACHO_SYMBOL_FLAG_DEFINED; |
| } |
| |
| /* Return either ORIG or: |
| |
| (const:P (unspec:P [ORIG] UNSPEC_MACHOPIC_OFFSET)) |
| |
| depending on MACHO_DYNAMIC_NO_PIC_P. */ |
| rtx |
| machopic_gen_offset (rtx orig) |
| { |
| if (MACHO_DYNAMIC_NO_PIC_P) |
| return orig; |
| else |
| { |
| /* Play games to avoid marking the function as needing pic if we |
| are being called as part of the cost-estimation process. */ |
| if (current_ir_type () != IR_GIMPLE || currently_expanding_to_rtl) |
| crtl->uses_pic_offset_table = 1; |
| orig = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, orig), |
| UNSPEC_MACHOPIC_OFFSET); |
| return gen_rtx_CONST (Pmode, orig); |
| } |
| } |
| |
| static GTY(()) const char * function_base_func_name = NULL; |
| static GTY(()) unsigned current_pic_label_num = 0; |
| static GTY(()) unsigned emitted_pic_label_num = 0; |
| |
| /* We need to keep one picbase label per function, but (when we emit code |
| to reload the picbase for setjump receiver) we might need to check for |
| a second use. So, only update the picbase label counter when we see a |
| new function. When there's no function decl, we assume that the call is |
| from the x86 stub generation code. */ |
| static void |
| update_pic_label_number_if_needed (void) |
| { |
| if (current_function_decl) |
| { |
| |
| const char *current_name = |
| IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (current_function_decl)); |
| if (function_base_func_name != current_name) |
| { |
| ++current_pic_label_num; |
| function_base_func_name = current_name; |
| } |
| } |
| else |
| { |
| ++current_pic_label_num; |
| function_base_func_name = "L_machopic_stub_dummy"; |
| } |
| } |
| |
| void |
| machopic_output_function_base_name (FILE *file) |
| { |
| /* We should only get here for -fPIC. */ |
| gcc_checking_assert (MACHOPIC_PURE); |
| |
| update_pic_label_number_if_needed (); |
| fprintf (file, "L%u$pb", current_pic_label_num); |
| } |
| |
| char curr_picbasename[32]; |
| |
| const char * |
| machopic_get_function_picbase (void) |
| { |
| /* We should only get here for -fPIC. */ |
| gcc_checking_assert (MACHOPIC_PURE); |
| |
| update_pic_label_number_if_needed (); |
| snprintf (curr_picbasename, 32, "L%u$pb", current_pic_label_num); |
| return (const char *) curr_picbasename; |
| } |
| |
| bool |
| machopic_should_output_picbase_label (void) |
| { |
| update_pic_label_number_if_needed (); |
| |
| if (current_pic_label_num == emitted_pic_label_num) |
| return false; |
| |
| emitted_pic_label_num = current_pic_label_num; |
| return true; |
| } |
| |
| /* The suffix attached to non-lazy pointer symbols. */ |
| #define NON_LAZY_POINTER_SUFFIX "$non_lazy_ptr" |
| /* The suffix attached to stub symbols. */ |
| #define STUB_SUFFIX "$stub" |
| |
| typedef struct GTY ((for_user)) machopic_indirection |
| { |
| /* The SYMBOL_REF for the entity referenced. */ |
| rtx symbol; |
| /* The name of the stub or non-lazy pointer. */ |
| const char * ptr_name; |
| /* True iff this entry is for a stub (as opposed to a non-lazy |
| pointer). */ |
| bool stub_p; |
| /* True iff this stub or pointer has been referenced. */ |
| bool used; |
| /* True iff a non-lazy symbol pointer should be emitted into the .data |
| section, rather than the non-lazy symbol pointers section. The cases |
| for which this occurred seem to have been unintentional, and later |
| toolchains emit all of the indirections to the 'usual' section. We |
| are keeping this in case it is necessary to preserve compatibility with |
| older toolchains. */ |
| bool nlsp_in_data_section; |
| } machopic_indirection; |
| |
| struct indirection_hasher : ggc_ptr_hash<machopic_indirection> |
| { |
| typedef const char *compare_type; |
| static hashval_t hash (machopic_indirection *); |
| static bool equal (machopic_indirection *, const char *); |
| }; |
| |
| /* A table mapping stub names and non-lazy pointer names to |
| SYMBOL_REFs for the stubbed-to and pointed-to entities. */ |
| |
| static GTY (()) hash_table<indirection_hasher> *machopic_indirections; |
| |
| /* Return a hash value for a SLOT in the indirections hash table. */ |
| |
| hashval_t |
| indirection_hasher::hash (machopic_indirection *p) |
| { |
| return htab_hash_string (p->ptr_name); |
| } |
| |
| /* Returns true if the KEY is the same as that associated with |
| SLOT. */ |
| |
| bool |
| indirection_hasher::equal (machopic_indirection *s, const char *k) |
| { |
| return strcmp (s->ptr_name, k) == 0; |
| } |
| |
| /* Return the name of the non-lazy pointer (if STUB_P is false) or |
| stub (if STUB_B is true) corresponding to the given name. |
| |
| PR71767 - If we have a situation like: |
| |
| global_weak_symbol: |
| .... |
| Lnon_weak_local: |
| .... |
| |
| ld64 will be unable to split this into two atoms (because the "L" makes |
| the second symbol 'invisible'). This means that legitimate direct accesses |
| to the second symbol will appear to be direct accesses to an atom of type |
| weak, global which are not allowed. |
| |
| To avoid this, we make any data-section indirections have a leading 'l' |
| (lower-case L) which has a special meaning: linker can see this and use |
| it to determine atoms, but it is not placed into the final symbol table. |
| |
| Symbols in the non-lazy symbol pointers section (or stubs) do not have this |
| problem because ld64 already knows the size of each entry. |
| */ |
| |
| const char * |
| machopic_indirection_name (rtx sym_ref, bool stub_p) |
| { |
| const char *name = XSTR (sym_ref, 0); |
| tree id = maybe_get_identifier (name); |
| if (id) |
| { |
| tree id_orig = id; |
| |
| while (IDENTIFIER_TRANSPARENT_ALIAS (id)) |
| id = TREE_CHAIN (id); |
| if (id != id_orig) |
| name = IDENTIFIER_POINTER (id); |
| } |
| |
| const char *prefix = user_label_prefix; |
| /* If we are emitting the label 'verbatim' then omit the U_L_P and count |
| the name without the leading '*'. */ |
| if (name[0] == '*') |
| { |
| prefix = ""; |
| ++name; |
| } |
| |
| /* Here we are undoing a number of causes that placed some indirections |
| (apparently erroneously) into the .data section. Specifically, some |
| symbols that are ABI mandated indirections and some hidden symbols |
| were being placed there - which cause difficulties with later |
| versions of ld64. Iff (after these checks) some symbol still gets an |
| indirection in the data section, we want to adjust the indirection |
| name to be linker visible to deal with PR71767 (notes above). */ |
| bool nlsp_in_data_section = |
| ! MACHO_SYMBOL_MUST_INDIRECT_P (sym_ref) |
| && ! MACHO_SYMBOL_HIDDEN_VIS_P (sym_ref) |
| && (machopic_symbol_defined_p (sym_ref) || SYMBOL_REF_LOCAL_P (sym_ref)) |
| && ! indirect_data (sym_ref); |
| |
| const char *suffix = stub_p ? STUB_SUFFIX : NON_LAZY_POINTER_SUFFIX; |
| /* If the indirection is in the data section, let the linker see it. */ |
| char L_or_l = (!stub_p && nlsp_in_data_section) ? 'l' : 'L'; |
| /* We have mangled symbols with spaces and punctuation which typically |
| need surrounding in quotes for the assembler to consume them. */ |
| const char *quote = name_needs_quotes (name) ? "\"" : ""; |
| char *buffer = XALLOCAVEC (char, 2 /* strlen ("&L") or ("&l") */ |
| + strlen (prefix) |
| + strlen (name) |
| + strlen (suffix) |
| + 2 * strlen (quote) |
| + 1 /* '\0' */); |
| |
| /* Construct the name of the non-lazy pointer or stub. */ |
| sprintf (buffer, "&%s%c%s%s%s%s", quote, L_or_l, prefix, name, |
| suffix, quote); |
| |
| if (!machopic_indirections) |
| machopic_indirections = hash_table<indirection_hasher>::create_ggc (37); |
| |
| machopic_indirection **slot |
| = machopic_indirections->find_slot_with_hash (buffer, |
| htab_hash_string (buffer), |
| INSERT); |
| machopic_indirection *p; |
| if (*slot) |
| p = *slot; |
| else |
| { |
| p = ggc_alloc<machopic_indirection> (); |
| p->symbol = sym_ref; |
| p->ptr_name = xstrdup (buffer); |
| p->stub_p = stub_p; |
| p->used = false; |
| p->nlsp_in_data_section = nlsp_in_data_section; |
| *slot = p; |
| } |
| |
| return p->ptr_name; |
| } |
| |
| /* If NAME is the name of a stub or a non-lazy pointer , mark the stub |
| or non-lazy pointer as used -- and mark the object to which the |
| pointer/stub refers as used as well, since the pointer/stub will |
| emit a reference to it. */ |
| |
| void |
| machopic_validate_stub_or_non_lazy_ptr (const char *name) |
| { |
| machopic_indirection *p |
| = machopic_indirections->find_with_hash (name, htab_hash_string (name)); |
| if (p && ! p->used) |
| { |
| const char *real_name; |
| tree id; |
| |
| p->used = true; |
| |
| /* Do what output_addr_const will do when we actually call it. */ |
| if (SYMBOL_REF_DECL (p->symbol)) |
| mark_decl_referenced (SYMBOL_REF_DECL (p->symbol)); |
| |
| real_name = targetm.strip_name_encoding (XSTR (p->symbol, 0)); |
| |
| id = maybe_get_identifier (real_name); |
| if (id) |
| mark_referenced (id); |
| } |
| } |
| |
| /* Transform ORIG, which may be any data source, to the corresponding |
| source using indirections. */ |
| |
| rtx |
| machopic_indirect_data_reference (rtx orig, rtx reg) |
| { |
| rtx ptr_ref = orig; |
| |
| if (! MACHOPIC_INDIRECT) |
| return orig; |
| |
| if (GET_CODE (orig) == SYMBOL_REF) |
| { |
| int defined = machopic_data_defined_p (orig); |
| |
| if (defined && MACHO_DYNAMIC_NO_PIC_P) |
| { |
| if (DARWIN_PPC) |
| { |
| /* Create a new register for CSE opportunities. */ |
| rtx hi_reg = (!can_create_pseudo_p () ? reg : gen_reg_rtx (Pmode)); |
| emit_insn (gen_macho_high (Pmode, hi_reg, orig)); |
| emit_insn (gen_macho_low (Pmode, reg, hi_reg, orig)); |
| return reg; |
| } |
| else if (DARWIN_X86) |
| return orig; |
| else |
| /* some other cpu -- writeme! */ |
| gcc_unreachable (); |
| } |
| else if (defined && ! MACHO_SYMBOL_MUST_INDIRECT_P (orig)) |
| { |
| rtx offset = NULL; |
| if (DARWIN_PPC || HAVE_lo_sum) |
| offset = machopic_gen_offset (orig); |
| |
| if (DARWIN_PPC) |
| { |
| rtx hi_sum_reg = (!can_create_pseudo_p () |
| ? reg |
| : gen_reg_rtx (Pmode)); |
| |
| gcc_assert (reg); |
| |
| emit_insn (gen_rtx_SET (hi_sum_reg, |
| gen_rtx_PLUS (Pmode, pic_offset_table_rtx, |
| gen_rtx_HIGH (Pmode, offset)))); |
| emit_insn (gen_rtx_SET (reg, |
| gen_rtx_LO_SUM (Pmode, hi_sum_reg, |
| copy_rtx (offset)))); |
| |
| orig = reg; |
| } |
| else if (HAVE_lo_sum) |
| { |
| gcc_assert (reg); |
| |
| emit_insn (gen_rtx_SET (reg, gen_rtx_HIGH (Pmode, offset))); |
| emit_insn (gen_rtx_SET (reg, gen_rtx_LO_SUM (Pmode, reg, |
| copy_rtx (offset)))); |
| emit_use (pic_offset_table_rtx); |
| |
| orig = gen_rtx_PLUS (Pmode, pic_offset_table_rtx, reg); |
| } |
| return orig; |
| } |
| |
| ptr_ref = (gen_rtx_SYMBOL_REF |
| (Pmode, |
| machopic_indirection_name (orig, /*stub_p=*/false))); |
| |
| SYMBOL_REF_DATA (ptr_ref) = SYMBOL_REF_DATA (orig); |
| SYMBOL_REF_FLAGS (ptr_ref) |= MACHO_SYMBOL_FLAG_INDIRECTION; |
| |
| ptr_ref = gen_const_mem (Pmode, ptr_ref); |
| machopic_define_symbol (ptr_ref); |
| |
| if (DARWIN_X86 |
| && reg |
| && MACHO_DYNAMIC_NO_PIC_P) |
| { |
| emit_insn (gen_rtx_SET (reg, ptr_ref)); |
| ptr_ref = reg; |
| } |
| |
| return ptr_ref; |
| } |
| else if (GET_CODE (orig) == CONST) |
| { |
| /* If "(const (plus ...", walk the PLUS and return that result. |
| PLUS processing (below) will restore the "(const ..." if |
| appropriate. */ |
| if (GET_CODE (XEXP (orig, 0)) == PLUS) |
| return machopic_indirect_data_reference (XEXP (orig, 0), reg); |
| else |
| return orig; |
| } |
| else if (GET_CODE (orig) == MEM) |
| { |
| XEXP (ptr_ref, 0) = |
| machopic_indirect_data_reference (XEXP (orig, 0), reg); |
| return ptr_ref; |
| } |
| else if (GET_CODE (orig) == PLUS) |
| { |
| rtx base, result; |
| |
| /* Legitimize both operands of the PLUS. */ |
| base = machopic_indirect_data_reference (XEXP (orig, 0), reg); |
| orig = machopic_indirect_data_reference (XEXP (orig, 1), |
| (base == reg ? 0 : reg)); |
| if (MACHOPIC_INDIRECT && (GET_CODE (orig) == CONST_INT)) |
| result = plus_constant (Pmode, base, INTVAL (orig)); |
| else |
| result = gen_rtx_PLUS (Pmode, base, orig); |
| |
| if (MACHOPIC_JUST_INDIRECT && GET_CODE (base) == MEM) |
| { |
| if (reg) |
| { |
| emit_move_insn (reg, result); |
| result = reg; |
| } |
| else |
| { |
| result = force_reg (GET_MODE (result), result); |
| } |
| } |
| |
| return result; |
| } |
| return ptr_ref; |
| } |
| |
| /* Transform TARGET (a MEM), which is a function call target, to the |
| corresponding symbol_stub if necessary. Return a new MEM. */ |
| |
| rtx |
| machopic_indirect_call_target (rtx target) |
| { |
| if (! darwin_symbol_stubs) |
| return target; |
| |
| if (GET_CODE (target) != MEM) |
| return target; |
| |
| if (MACHOPIC_INDIRECT |
| && GET_CODE (XEXP (target, 0)) == SYMBOL_REF |
| && ! MACHO_SYMBOL_DEFINED_P (XEXP (target, 0))) |
| { |
| rtx sym_ref = XEXP (target, 0); |
| const char *stub_name = machopic_indirection_name (sym_ref, |
| /*stub_p=*/true); |
| machine_mode mode = GET_MODE (sym_ref); |
| |
| XEXP (target, 0) = gen_rtx_SYMBOL_REF (mode, stub_name); |
| SYMBOL_REF_DATA (XEXP (target, 0)) = SYMBOL_REF_DATA (sym_ref); |
| SYMBOL_REF_FLAGS (XEXP (target, 0)) |= MACHO_SYMBOL_FLAG_INDIRECTION; |
| MEM_READONLY_P (target) = 1; |
| MEM_NOTRAP_P (target) = 1; |
| } |
| |
| return target; |
| } |
| |
| rtx |
| machopic_legitimize_pic_address (rtx orig, machine_mode mode, rtx reg) |
| { |
| rtx pic_ref = orig; |
| |
| if (! MACHOPIC_INDIRECT) |
| return orig; |
| |
| /* First handle a simple SYMBOL_REF or LABEL_REF */ |
| if (GET_CODE (orig) == LABEL_REF |
| || GET_CODE (orig) == SYMBOL_REF) |
| { |
| /* addr(foo) = &func+(foo-func) */ |
| orig = machopic_indirect_data_reference (orig, reg); |
| |
| if (GET_CODE (orig) == PLUS |
| && GET_CODE (XEXP (orig, 0)) == REG) |
| { |
| if (reg == 0) |
| return force_reg (mode, orig); |
| |
| emit_move_insn (reg, orig); |
| return reg; |
| } |
| |
| if (GET_CODE (orig) == MEM) |
| { |
| if (reg == 0) |
| { |
| gcc_assert (!lra_in_progress); |
| reg = gen_reg_rtx (Pmode); |
| } |
| |
| #if HAVE_lo_sum |
| if (MACHO_DYNAMIC_NO_PIC_P |
| && (GET_CODE (XEXP (orig, 0)) == SYMBOL_REF |
| || GET_CODE (XEXP (orig, 0)) == LABEL_REF)) |
| { |
| #if defined (TARGET_TOC) /* ppc */ |
| rtx temp_reg = (!can_create_pseudo_p () |
| ? reg : |
| gen_reg_rtx (Pmode)); |
| rtx asym = XEXP (orig, 0); |
| rtx mem; |
| |
| emit_insn (gen_macho_high (Pmode, temp_reg, asym)); |
| mem = gen_const_mem (GET_MODE (orig), |
| gen_rtx_LO_SUM (Pmode, temp_reg, |
| copy_rtx (asym))); |
| emit_insn (gen_rtx_SET (reg, mem)); |
| #else |
| /* Some other CPU -- WriteMe! but right now there are no other |
| platforms that can use dynamic-no-pic */ |
| gcc_unreachable (); |
| #endif |
| pic_ref = reg; |
| } |
| else |
| if (GET_CODE (XEXP (orig, 0)) == SYMBOL_REF |
| || GET_CODE (XEXP (orig, 0)) == LABEL_REF) |
| { |
| rtx offset = machopic_gen_offset (XEXP (orig, 0)); |
| #if defined (TARGET_TOC) /* i.e., PowerPC */ |
| /* Generating a new reg may expose opportunities for |
| common subexpression elimination. */ |
| rtx hi_sum_reg = (!can_create_pseudo_p () |
| ? reg |
| : gen_reg_rtx (Pmode)); |
| rtx mem; |
| rtx sum; |
| |
| sum = gen_rtx_HIGH (Pmode, offset); |
| if (! MACHO_DYNAMIC_NO_PIC_P) |
| sum = gen_rtx_PLUS (Pmode, pic_offset_table_rtx, sum); |
| |
| emit_insn (gen_rtx_SET (hi_sum_reg, sum)); |
| |
| mem = gen_const_mem (GET_MODE (orig), |
| gen_rtx_LO_SUM (Pmode, |
| hi_sum_reg, |
| copy_rtx (offset))); |
| rtx_insn *insn = emit_insn (gen_rtx_SET (reg, mem)); |
| set_unique_reg_note (insn, REG_EQUAL, pic_ref); |
| |
| pic_ref = reg; |
| #else |
| emit_use (gen_rtx_REG (Pmode, PIC_OFFSET_TABLE_REGNUM)); |
| |
| emit_insn (gen_rtx_SET (reg, |
| gen_rtx_HIGH (Pmode, |
| gen_rtx_CONST (Pmode, |
| offset)))); |
| emit_insn (gen_rtx_SET (reg, |
| gen_rtx_LO_SUM (Pmode, reg, |
| gen_rtx_CONST (Pmode, |
| copy_rtx (offset))))); |
| pic_ref = gen_rtx_PLUS (Pmode, |
| pic_offset_table_rtx, reg); |
| #endif |
| } |
| else |
| #endif /* HAVE_lo_sum */ |
| { |
| rtx pic = pic_offset_table_rtx; |
| if (GET_CODE (pic) != REG) |
| { |
| emit_move_insn (reg, pic); |
| pic = reg; |
| } |
| |
| if (lra_in_progress && HARD_REGISTER_P (pic)) |
| df_set_regs_ever_live (REGNO (pic), true); |
| pic_ref = gen_rtx_PLUS (Pmode, pic, |
| machopic_gen_offset (XEXP (orig, 0))); |
| } |
| |
| #if !defined (TARGET_TOC) |
| emit_move_insn (reg, pic_ref); |
| pic_ref = gen_const_mem (GET_MODE (orig), reg); |
| #endif |
| } |
| else |
| { |
| |
| #if HAVE_lo_sum |
| if (GET_CODE (orig) == SYMBOL_REF |
| || GET_CODE (orig) == LABEL_REF) |
| { |
| rtx offset = machopic_gen_offset (orig); |
| #if defined (TARGET_TOC) /* i.e., PowerPC */ |
| rtx hi_sum_reg; |
| |
| if (reg == 0) |
| { |
| gcc_assert (!lra_in_progress); |
| reg = gen_reg_rtx (Pmode); |
| } |
| |
| hi_sum_reg = reg; |
| |
| emit_insn (gen_rtx_SET (hi_sum_reg, |
| (MACHO_DYNAMIC_NO_PIC_P) |
| ? gen_rtx_HIGH (Pmode, offset) |
| : gen_rtx_PLUS (Pmode, |
| pic_offset_table_rtx, |
| gen_rtx_HIGH (Pmode, |
| offset)))); |
| emit_insn (gen_rtx_SET (reg, |
| gen_rtx_LO_SUM (Pmode, |
| hi_sum_reg, |
| copy_rtx (offset)))); |
| pic_ref = reg; |
| #else |
| emit_insn (gen_rtx_SET (reg, gen_rtx_HIGH (Pmode, offset))); |
| emit_insn (gen_rtx_SET (reg, |
| gen_rtx_LO_SUM (Pmode, reg, |
| copy_rtx (offset)))); |
| pic_ref = gen_rtx_PLUS (Pmode, |
| pic_offset_table_rtx, reg); |
| #endif |
| } |
| else |
| #endif /* HAVE_lo_sum */ |
| { |
| if (REG_P (orig) |
| || GET_CODE (orig) == SUBREG) |
| { |
| return orig; |
| } |
| else |
| { |
| rtx pic = pic_offset_table_rtx; |
| if (GET_CODE (pic) != REG) |
| { |
| emit_move_insn (reg, pic); |
| pic = reg; |
| } |
| |
| if (lra_in_progress && HARD_REGISTER_P (pic)) |
| df_set_regs_ever_live (REGNO (pic), true); |
| pic_ref = gen_rtx_PLUS (Pmode, |
| pic, |
| machopic_gen_offset (orig)); |
| } |
| } |
| } |
| |
| if (GET_CODE (pic_ref) != REG) |
| { |
| if (reg != 0) |
| { |
| emit_move_insn (reg, pic_ref); |
| return reg; |
| } |
| else |
| { |
| return force_reg (mode, pic_ref); |
| } |
| } |
| else |
| { |
| return pic_ref; |
| } |
| } |
| else if (GET_CODE (orig) == PLUS |
| && (GET_CODE (XEXP (orig, 0)) == MEM |
| || GET_CODE (XEXP (orig, 0)) == SYMBOL_REF |
| || GET_CODE (XEXP (orig, 0)) == LABEL_REF) |
| && XEXP (orig, 0) != pic_offset_table_rtx |
| && GET_CODE (XEXP (orig, 1)) != REG) |
| |
| { |
| rtx base; |
| int is_complex = (GET_CODE (XEXP (orig, 0)) == MEM); |
| |
| base = machopic_legitimize_pic_address (XEXP (orig, 0), Pmode, reg); |
| orig = machopic_legitimize_pic_address (XEXP (orig, 1), |
| Pmode, (base == reg ? 0 : reg)); |
| if (GET_CODE (orig) == CONST_INT) |
| { |
| pic_ref = plus_constant (Pmode, base, INTVAL (orig)); |
| is_complex = 1; |
| } |
| else |
| pic_ref = gen_rtx_PLUS (Pmode, base, orig); |
| |
| if (reg && is_complex) |
| { |
| emit_move_insn (reg, pic_ref); |
| pic_ref = reg; |
| } |
| /* Likewise, should we set special REG_NOTEs here? */ |
| } |
| else if (GET_CODE (orig) == CONST) |
| { |
| return machopic_legitimize_pic_address (XEXP (orig, 0), Pmode, reg); |
| } |
| else if (GET_CODE (orig) == MEM |
| && GET_CODE (XEXP (orig, 0)) == SYMBOL_REF) |
| { |
| rtx addr = machopic_legitimize_pic_address (XEXP (orig, 0), Pmode, reg); |
| addr = replace_equiv_address (orig, addr); |
| emit_move_insn (reg, addr); |
| pic_ref = reg; |
| } |
| |
| return pic_ref; |
| } |
| |
| /* Callbacks to output the stub or non-lazy pointers. |
| Each works on the item in *SLOT,if it has been used. |
| DATA is the FILE* for assembly output. |
| Called from htab_traverses, invoked from machopic_finish(). */ |
| |
| int |
| machopic_output_data_section_indirection (machopic_indirection **slot, |
| FILE *asm_out_file) |
| { |
| machopic_indirection *p = *slot; |
| |
| if (!p->used || !p->nlsp_in_data_section) |
| return 1; |
| |
| rtx symbol = p->symbol; |
| /* The original symbol name. */ |
| const char *sym_name = XSTR (symbol, 0); |
| /* The name of the indirection symbol. */ |
| const char *ptr_name = p->ptr_name; |
| |
| switch_to_section (data_section); |
| assemble_align (GET_MODE_ALIGNMENT (Pmode)); |
| assemble_label (asm_out_file, ptr_name); |
| assemble_integer (gen_rtx_SYMBOL_REF (Pmode, sym_name), |
| GET_MODE_SIZE (Pmode), |
| GET_MODE_ALIGNMENT (Pmode), 1); |
| |
| return 1; |
| } |
| |
| int |
| machopic_output_stub_indirection (machopic_indirection **slot, |
| FILE *asm_out_file) |
| { |
| machopic_indirection *p = *slot; |
| |
| if (!p->used || !p->stub_p) |
| return 1; |
| |
| rtx symbol = p->symbol; |
| /* The original symbol name. */ |
| const char *sym_name = XSTR (symbol, 0); |
| /* The name of the stub symbol. */ |
| const char *ptr_name = p->ptr_name; |
| |
| tree id = maybe_get_identifier (sym_name); |
| if (id) |
| { |
| tree id_orig = id; |
| |
| while (IDENTIFIER_TRANSPARENT_ALIAS (id)) |
| id = TREE_CHAIN (id); |
| if (id != id_orig) |
| sym_name = IDENTIFIER_POINTER (id); |
| } |
| |
| char *sym = XALLOCAVEC (char, strlen (sym_name) + 2); |
| if (sym_name[0] == '*' || sym_name[0] == '&') |
| strcpy (sym, sym_name + 1); |
| else if (sym_name[0] == '-' || sym_name[0] == '+') |
| strcpy (sym, sym_name); |
| else |
| sprintf (sym, "%s%s", user_label_prefix, sym_name); |
| |
| char *stub = XALLOCAVEC (char, strlen (ptr_name) + 2); |
| if (ptr_name[0] == '*' || ptr_name[0] == '&') |
| strcpy (stub, ptr_name + 1); |
| else |
| sprintf (stub, "%s%s", user_label_prefix, ptr_name); |
| |
| machopic_output_stub (asm_out_file, sym, stub); |
| |
| return 1; |
| } |
| |
| int |
| machopic_output_indirection (machopic_indirection **slot, FILE *asm_out_file) |
| { |
| machopic_indirection *p = *slot; |
| |
| if (!p->used || p->stub_p || p->nlsp_in_data_section) |
| return 1; |
| |
| rtx symbol = p->symbol; |
| /* The original symbol name. */ |
| const char *sym_name = XSTR (symbol, 0); |
| /* The nonlazy-stub symbol name. */ |
| const char *ptr_name = p->ptr_name; |
| |
| switch_to_section (darwin_sections[machopic_nl_symbol_ptr_section]); |
| |
| /* Mach-O symbols are passed around in code through indirect references and |
| the original symbol_ref hasn't passed through the generic handling and |
| reference-catching in output_operand, so we need to manually mark weak |
| references as such. */ |
| |
| if (SYMBOL_REF_WEAK (symbol)) |
| { |
| tree decl = SYMBOL_REF_DECL (symbol); |
| gcc_checking_assert (DECL_P (decl)); |
| |
| if (decl != NULL_TREE |
| && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl) |
| /* Handle only actual external-only definitions, not |
| e.g. extern inline code or variables for which |
| storage has been allocated. */ |
| && !TREE_STATIC (decl)) |
| { |
| fputs ("\t.weak_reference ", asm_out_file); |
| assemble_name (asm_out_file, sym_name); |
| fputc ('\n', asm_out_file); |
| } |
| } |
| |
| assemble_name (asm_out_file, ptr_name); |
| fprintf (asm_out_file, ":\n"); |
| |
| fprintf (asm_out_file, "\t.indirect_symbol "); |
| assemble_name (asm_out_file, sym_name); |
| fprintf (asm_out_file, "\n"); |
| |
| /* Variables that are marked with MACHO_SYMBOL_FLAG_STATIC need to |
| have their symbol name instead of 0 in the second entry of |
| the non-lazy symbol pointer data structure when they are |
| defined. This allows the runtime to rebind newer instances |
| of the translation unit with the original instance of the |
| symbol. */ |
| |
| rtx init = const0_rtx; |
| if (MACHO_SYMBOL_STATIC_P (symbol) && machopic_symbol_defined_p (symbol)) |
| init = gen_rtx_SYMBOL_REF (Pmode, sym_name); |
| |
| assemble_integer (init, GET_MODE_SIZE (Pmode), |
| GET_MODE_ALIGNMENT (Pmode), 1); |
| |
| return 1; |
| } |
| |
| static void |
| machopic_finish (FILE *asm_out_file) |
| { |
| if (!machopic_indirections) |
| return; |
| |
| /* First output an symbol indirections that have been placed into .data |
| (we don't expect these now). */ |
| machopic_indirections->traverse_noresize |
| <FILE *, machopic_output_data_section_indirection> (asm_out_file); |
| |
| machopic_indirections->traverse_noresize |
| <FILE *, machopic_output_stub_indirection> (asm_out_file); |
| |
| machopic_indirections->traverse_noresize |
| <FILE *, machopic_output_indirection> (asm_out_file); |
| } |
| |
| int |
| machopic_operand_p (rtx op) |
| { |
| if (MACHOPIC_JUST_INDIRECT) |
| return (GET_CODE (op) == SYMBOL_REF |
| && machopic_symbol_defined_p (op)); |
| else |
| return (GET_CODE (op) == CONST |
| && GET_CODE (XEXP (op, 0)) == UNSPEC |
| && XINT (XEXP (op, 0), 1) == UNSPEC_MACHOPIC_OFFSET); |
| } |
| |
| /* This function: |
| computes and caches a series of flags that characterise the symbol's |
| properties that affect Mach-O code gen (including accidental cases |
| from older toolchains). |
| |
| TODO: |
| Here we also need to do enough analysis to determine if a symbol's |
| name needs to be made linker-visible. This is more tricky - since |
| it depends on whether we've previously seen a global weak definition |
| in the same section. |
| */ |
| |
| void |
| darwin_encode_section_info (tree decl, rtx rtl, int first) |
| { |
| /* Careful not to prod global register variables. */ |
| if (!MEM_P (rtl)) |
| return; |
| |
| /* Do the standard encoding things first; this sets: |
| SYMBOL_FLAG_FUNCTION, |
| SYMBOL_FLAG_LOCAL, (binds_local_p) |
| TLS_MODEL, SYMBOL_FLAG_SMALL |
| SYMBOL_FLAG_EXTERNAL. */ |
| default_encode_section_info (decl, rtl, first); |
| |
| if (! VAR_OR_FUNCTION_DECL_P (decl)) |
| return; |
| |
| rtx sym_ref = XEXP (rtl, 0); |
| if (VAR_P (decl)) |
| SYMBOL_REF_FLAGS (sym_ref) |= MACHO_SYMBOL_FLAG_VARIABLE; |
| |
| /* Only really common if there's no initialiser. */ |
| bool really_common_p = (DECL_COMMON (decl) |
| && (DECL_INITIAL (decl) == NULL |
| || (!in_lto_p |
| && DECL_INITIAL (decl) == error_mark_node))); |
| |
| /* For Darwin, if we have specified visibility and it's not the default |
| that's counted 'hidden'. */ |
| if (DECL_VISIBILITY_SPECIFIED (decl) |
| && DECL_VISIBILITY (decl) != VISIBILITY_DEFAULT) |
| SYMBOL_REF_FLAGS (sym_ref) |= MACHO_SYMBOL_FLAG_HIDDEN_VIS; |
| |
| if (!DECL_EXTERNAL (decl) |
| && (!TREE_PUBLIC (decl) || !DECL_WEAK (decl)) |
| && ! lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)) |
| && ((TREE_STATIC (decl) |
| && (!DECL_COMMON (decl) || !TREE_PUBLIC (decl))) |
| || (!DECL_COMMON (decl) && DECL_INITIAL (decl) |
| && DECL_INITIAL (decl) != error_mark_node))) |
| SYMBOL_REF_FLAGS (sym_ref) |= MACHO_SYMBOL_FLAG_DEFINED; |
| |
| if (! TREE_PUBLIC (decl)) |
| SYMBOL_REF_FLAGS (sym_ref) |= MACHO_SYMBOL_FLAG_STATIC; |
| |
| /* Short cut check for Darwin 'must indirect' rules. */ |
| if (really_common_p |
| || (DECL_WEAK (decl) && ! MACHO_SYMBOL_HIDDEN_VIS_P (sym_ref)) |
| || lookup_attribute ("weakref", DECL_ATTRIBUTES (decl))) |
| SYMBOL_REF_FLAGS (sym_ref) |= MACHO_SYMBOL_FLAG_MUST_INDIRECT; |
| |
| #if DARWIN_PPC |
| /* Objective C V2 (m64) IVAR offset refs from Apple GCC-4.x have an |
| indirection for m64 code on PPC. Historically, these indirections |
| also appear in the .data section. */ |
| tree o2meta = lookup_attribute ("OBJC2META", DECL_ATTRIBUTES (decl)); |
| o2meta = o2meta ? TREE_VALUE (o2meta) : NULL_TREE; |
| |
| if (o2meta && startswith (IDENTIFIER_POINTER (o2meta), "V2_IVRF")) |
| SYMBOL_REF_FLAGS (sym_ref) |= MACHO_SYMBOL_FLAG_MUST_INDIRECT; |
| #endif |
| } |
| |
| void |
| darwin_mark_decl_preserved (const char *name) |
| { |
| /* Actually we shouldn't mark any local symbol this way, but for now |
| this only happens with ObjC meta-data. */ |
| if (darwin_label_is_anonymous_local_objc_name (name)) |
| return; |
| |
| fprintf (asm_out_file, "\t.no_dead_strip "); |
| assemble_name (asm_out_file, name); |
| fputc ('\n', asm_out_file); |
| } |
| |
| static section * |
| darwin_rodata_section (int use_coal, bool zsize, int reloc) |
| { |
| return (use_coal |
| ? darwin_sections[const_coal_section] |
| : (zsize ? darwin_sections[zobj_const_section] |
| : reloc ? darwin_sections[const_data_section] |
| : darwin_sections[const_section])); |
| } |
| |
| static section * |
| darwin_mergeable_string_section (tree exp, |
| unsigned HOST_WIDE_INT align) |
| { |
| /* Darwin's ld expects to see non-writable string literals in the .cstring |
| section. Later versions of ld check and complain when CFStrings are |
| enabled. Therefore we shall force the strings into .cstring since we |
| don't support writable ones anyway. */ |
| if ((darwin_constant_cfstrings || flag_merge_constants) |
| && TREE_CODE (exp) == STRING_CST |
| && TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE |
| && align <= 256 |
| && (int_size_in_bytes (TREE_TYPE (exp)) |
| == TREE_STRING_LENGTH (exp)) |
| && ((size_t) TREE_STRING_LENGTH (exp) |
| == strlen (TREE_STRING_POINTER (exp)) + 1)) |
| return darwin_sections[cstring_section]; |
| |
| if (DARWIN_SECTION_ANCHORS && flag_section_anchors |
| && TREE_CODE (exp) == STRING_CST |
| && TREE_STRING_LENGTH (exp) == 0) |
| return darwin_sections[zobj_const_section]; |
| |
| return readonly_data_section; |
| } |
| |
| #ifndef HAVE_GAS_LITERAL16 |
| #define HAVE_GAS_LITERAL16 0 |
| #endif |
| |
| static section * |
| darwin_mergeable_constant_section (tree exp, |
| unsigned HOST_WIDE_INT align, |
| bool zsize) |
| { |
| if (zsize) |
| return darwin_sections[zobj_const_section]; |
| |
| machine_mode mode = DECL_MODE (exp); |
| if (!flag_merge_constants |
| || mode == VOIDmode |
| || mode == BLKmode |
| || align < 8 |
| || align > 256 |
| || (align & (align -1)) != 0) |
| return readonly_data_section; |
| |
| /* This will ICE if the mode is not a constant size, but that is reasonable, |
| since one cannot put a variable-sized thing into a constant section, we |
| shouldn't be trying. */ |
| const unsigned int modesize = GET_MODE_BITSIZE (mode).to_constant (); |
| |
| if (modesize > align) |
| return readonly_data_section; |
| |
| tree size = TYPE_SIZE_UNIT (TREE_TYPE (exp)); |
| |
| if (TREE_CODE (size) != INTEGER_CST) |
| return readonly_data_section; |
| |
| unsigned isize = TREE_INT_CST_LOW (size); |
| if (isize == 4) |
| return darwin_sections[literal4_section]; |
| else if (isize == 8) |
| return darwin_sections[literal8_section]; |
| else if (HAVE_GAS_LITERAL16 |
| && TARGET_64BIT |
| && isize == 16) |
| return darwin_sections[literal16_section]; |
| |
| return readonly_data_section; |
| } |
| |
| section * |
| darwin_tm_clone_table_section (void) |
| { |
| return get_named_section (NULL, |
| "__DATA,__tm_clone_table,regular,no_dead_strip", |
| 3); |
| } |
| |
| int |
| machopic_reloc_rw_mask (void) |
| { |
| return MACHOPIC_INDIRECT ? 3 : 0; |
| } |
| |
| /* We have to deal with ObjC/C++ metadata section placement in the common |
| code, since it will also be called from LTO. |
| |
| Return metadata attributes, if present (searching for ABI=2 first) |
| Return NULL_TREE if no such attributes are found. */ |
| |
| static tree |
| is_objc_metadata (tree decl) |
| { |
| if (DECL_P (decl) |
| && (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == CONST_DECL) |
| && DECL_ATTRIBUTES (decl)) |
| { |
| tree meta = lookup_attribute ("OBJC2META", DECL_ATTRIBUTES (decl)); |
| if (meta) |
| return meta; |
| meta = lookup_attribute ("OBJC1META", DECL_ATTRIBUTES (decl)); |
| if (meta) |
| return meta; |
| } |
| return NULL_TREE; |
| } |
| |
| static int classes_seen; |
| static int objc_metadata_seen; |
| |
| /* Return the section required for Objective C ABI 2 metadata. */ |
| static section * |
| darwin_objc2_section (tree decl ATTRIBUTE_UNUSED, tree meta, section * base) |
| { |
| const char *p; |
| tree ident = TREE_VALUE (meta); |
| gcc_assert (TREE_CODE (ident) == IDENTIFIER_NODE); |
| p = IDENTIFIER_POINTER (ident); |
| |
| gcc_checking_assert (flag_next_runtime >= 1 && flag_objc_abi == 2); |
| |
| objc_metadata_seen = 1; |
| |
| if (base == data_section) |
| base = darwin_sections[objc2_metadata_section]; |
| |
| /* Most of the OBJC2 META-data end up in the base section, so check it |
| first. */ |
| if (startswith (p, "V2_BASE")) |
| return base; |
| else if (startswith (p, "V2_CNAM")) |
| return darwin_sections[objc2_class_names_section]; |
| else if (startswith (p, "V2_MNAM")) |
| return darwin_sections[objc2_method_names_section]; |
| else if (startswith (p, "V2_MTYP")) |
| return darwin_sections[objc2_method_types_section]; |
| else if (startswith (p, "V2_STRG")) |
| return darwin_sections[cstring_section]; |
| |
| else if (startswith (p, "G2_META") || startswith (p, "G2_CLAS")) |
| return darwin_sections[objc2_classdefs_section]; |
| else if (startswith (p, "V2_PCOL")) |
| return ld_uses_coal_sects ? darwin_sections[data_coal_section] |
| : darwin_sections[objc2_data_section]; |
| else if (startswith (p, "V2_MREF")) |
| return darwin_sections[objc2_message_refs_section]; |
| else if (startswith (p, "V2_CLRF")) |
| return darwin_sections[objc2_classrefs_section]; |
| else if (startswith (p, "V2_SURF")) |
| return darwin_sections[objc2_super_classrefs_section]; |
| else if (startswith (p, "V2_NLCL")) |
| return darwin_sections[objc2_nonlazy_class_section]; |
| else if (startswith (p, "V2_CLAB")) |
| { |
| classes_seen = 1; |
| return darwin_sections[objc2_classlist_section]; |
| } |
| else if (startswith (p, "V2_SRFS")) |
| return darwin_sections[objc2_selector_refs_section]; |
| else if (startswith (p, "V2_NLCA")) |
| return darwin_sections[objc2_nonlazy_category_section]; |
| else if (startswith (p, "V2_CALA")) |
| return darwin_sections[objc2_categorylist_section]; |
| |
| else if (startswith (p, "V2_PLST")) |
| return darwin_sections[objc2_protocollist_section]; |
| else if (startswith (p, "V2_PRFS")) |
| return darwin_sections[objc2_protocolrefs_section]; |
| |
| else if (startswith (p, "V2_INFO")) |
| return darwin_sections[objc2_image_info_section]; |
| |
| else if (startswith (p, "V2_EHTY")) |
| return ld_uses_coal_sects ? darwin_sections[data_coal_section] |
| : data_section; |
| |
| else if (startswith (p, "V2_CSTR")) |
| return darwin_sections[objc2_constant_string_object_section]; |
| |
| else if (startswith (p, "V2_IVRF")) |
| return darwin_sections[objc2_ivar_section]; |
| |
| /* Not recognized, default. */ |
| return base; |
| } |
| |
| /* Return the section required for Objective C ABI 0/1 metadata. */ |
| static section * |
| darwin_objc1_section (tree decl ATTRIBUTE_UNUSED, tree meta, section * base) |
| { |
| const char *p; |
| tree ident = TREE_VALUE (meta); |
| gcc_assert (TREE_CODE (ident) == IDENTIFIER_NODE); |
| p = IDENTIFIER_POINTER (ident); |
| |
| gcc_checking_assert (flag_next_runtime >= 1 && flag_objc_abi < 2); |
| |
| objc_metadata_seen = 1; |
| |
| /* String sections first, cos there are lots of strings. */ |
| if (startswith (p, "V1_STRG")) |
| return darwin_sections[cstring_section]; |
| else if (startswith (p, "V1_CLSN")) |
| return darwin_sections[objc_class_names_section]; |
| else if (startswith (p, "V1_METN")) |
| return darwin_sections[objc_meth_var_names_section]; |
| else if (startswith (p, "V1_METT")) |
| return darwin_sections[objc_meth_var_types_section]; |
| |
| else if (startswith (p, "V1_CLAS")) |
| { |
| classes_seen = 1; |
| return darwin_sections[objc_class_section]; |
| } |
| else if (startswith (p, "V1_META")) |
| return darwin_sections[objc_meta_class_section]; |
| else if (startswith (p, "V1_CATG")) |
| return darwin_sections[objc_category_section]; |
| else if (startswith (p, "V1_PROT")) |
| return darwin_sections[objc_protocol_section]; |
| |
| else if (startswith (p, "V1_CLCV")) |
| return darwin_sections[objc_class_vars_section]; |
| else if (startswith (p, "V1_CLIV")) |
| return darwin_sections[objc_instance_vars_section]; |
| |
| else if (startswith (p, "V1_CLCM")) |
| return darwin_sections[objc_cls_meth_section]; |
| else if (startswith (p, "V1_CLIM")) |
| return darwin_sections[objc_inst_meth_section]; |
| else if (startswith (p, "V1_CACM")) |
| return darwin_sections[objc_cat_cls_meth_section]; |
| else if (startswith (p, "V1_CAIM")) |
| return darwin_sections[objc_cat_inst_meth_section]; |
| else if (startswith (p, "V1_PNSM")) |
| return darwin_sections[objc_cat_inst_meth_section]; |
| else if (startswith (p, "V1_PCLM")) |
| return darwin_sections[objc_cat_cls_meth_section]; |
| |
| else if (startswith (p, "V1_CLPR")) |
| return darwin_sections[objc_cat_cls_meth_section]; |
| else if (startswith (p, "V1_CAPR")) |
| return darwin_sections[objc_category_section]; /* ??? CHECK me. */ |
| |
| else if (startswith (p, "V1_PRFS")) |
| return darwin_sections[objc_cat_cls_meth_section]; |
| else if (startswith (p, "V1_CLRF")) |
| return darwin_sections[objc_cls_refs_section]; |
| else if (startswith (p, "V1_SRFS")) |
| return darwin_sections[objc_selector_refs_section]; |
| |
| else if (startswith (p, "V1_MODU")) |
| return darwin_sections[objc_module_info_section]; |
| else if (startswith (p, "V1_SYMT")) |
| return darwin_sections[objc_symbols_section]; |
| else if (startswith (p, "V1_INFO")) |
| return darwin_sections[objc_image_info_section]; |
| |
| else if (startswith (p, "V1_PLST")) |
| return darwin_sections[objc1_prop_list_section]; |
| else if (startswith (p, "V1_PEXT")) |
| return darwin_sections[objc1_protocol_ext_section]; |
| else if (startswith (p, "V1_CEXT")) |
| return darwin_sections[objc1_class_ext_section]; |
| |
| else if (startswith (p, "V2_CSTR")) |
| return darwin_sections[objc_constant_string_object_section]; |
| |
| return base; |
| } |
| |
| section * |
| machopic_select_section (tree decl, |
| int reloc, |
| unsigned HOST_WIDE_INT align) |
| { |
| bool zsize, one, weak, use_coal, ro; |
| section *base_section = NULL; |
| |
| weak = (DECL_P (decl) |
| && DECL_WEAK (decl) |
| && !lookup_attribute ("weak_import", DECL_ATTRIBUTES (decl))); |
| |
| /* Darwin pads zero-sized objects with at least one byte, so that the ld64 |
| atom model is preserved (objects must have distinct regions starting with |
| a unique linker-visible symbol). |
| In order to support section anchors, we need to move objects with zero |
| size into sections which are marked as "no section anchors"; the padded |
| objects, obviously, have real sizes that differ from their DECL sizes. */ |
| zsize = DARWIN_SECTION_ANCHORS && flag_section_anchors; |
| |
| /* In the streaming of LTO symbol data, we might have a situation where the |
| var is incomplete or layout not finished (DECL_SIZE_UNIT is NULL_TREE). |
| We cannot tell if it is zero-sized then, but we can get the section |
| category correct so that nm reports the right kind of section |
| (e.g. BSS c.f. data). */ |
| zsize = (zsize |
| && DECL_P (decl) |
| && (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == CONST_DECL) |
| && DECL_SIZE_UNIT (decl) |
| && tree_to_uhwi (DECL_SIZE_UNIT (decl)) == 0); |
| |
| one = DECL_P (decl) |
| && TREE_CODE (decl) == VAR_DECL |
| && DECL_COMDAT_GROUP (decl); |
| |
| use_coal = (weak || one) && ld_uses_coal_sects; |
| |
| ro = TREE_READONLY (decl) || TREE_CONSTANT (decl) ; |
| |
| switch (categorize_decl_for_section (decl, reloc)) |
| { |
| case SECCAT_TEXT: |
| gcc_unreachable (); |
| break; |
| |
| case SECCAT_RODATA: |
| case SECCAT_SRODATA: |
| base_section = darwin_rodata_section (use_coal, zsize, reloc); |
| break; |
| |
| case SECCAT_RODATA_MERGE_STR: |
| base_section = darwin_mergeable_string_section (decl, align); |
| break; |
| |
| case SECCAT_RODATA_MERGE_STR_INIT: |
| base_section = darwin_mergeable_string_section (DECL_INITIAL (decl), align); |
| break; |
| |
| case SECCAT_RODATA_MERGE_CONST: |
| base_section = darwin_mergeable_constant_section (decl, align, zsize); |
| break; |
| |
| case SECCAT_DATA: |
| case SECCAT_DATA_REL: |
| case SECCAT_DATA_REL_LOCAL: |
| case SECCAT_DATA_REL_RO: |
| case SECCAT_DATA_REL_RO_LOCAL: |
| case SECCAT_SDATA: |
| case SECCAT_TDATA: |
| if (use_coal) |
| { |
| if (ro) |
| base_section = darwin_sections[const_data_coal_section]; |
| else |
| base_section = darwin_sections[data_coal_section]; |
| } |
| else if (zsize) |
| { |
| /* If we're doing section anchors, then punt zero-sized objects into |
| their own sections so that they don't interfere with offset |
| computation for the remaining vars. */ |
| if (ro) |
| base_section = darwin_sections[zobj_const_data_section]; |
| else |
| base_section = darwin_sections[zobj_data_section]; |
| } |
| else if (ro) |
| base_section = darwin_sections[const_data_section]; |
| else |
| base_section = data_section; |
| break; |
| case SECCAT_BSS: |
| case SECCAT_SBSS: |
| case SECCAT_TBSS: |
| if (use_coal) |
| base_section = darwin_sections[data_coal_section]; |
| else |
| { |
| if (!TREE_PUBLIC (decl)) |
| base_section = lcomm_section; |
| else if (bss_noswitch_section) |
| base_section = bss_noswitch_section; |
| else |
| base_section = data_section; |
| } |
| break; |
| |
| default: |
| gcc_unreachable (); |
| } |
| |
| /* Darwin weird special cases. |
| a) OBJC Meta-data. */ |
| if (DECL_P (decl) |
| && (TREE_CODE (decl) == VAR_DECL |
| || TREE_CODE (decl) == CONST_DECL) |
| && DECL_ATTRIBUTES (decl)) |
| { |
| tree meta = lookup_attribute ("OBJC2META", DECL_ATTRIBUTES (decl)); |
| if (meta) |
| return darwin_objc2_section (decl, meta, base_section); |
| meta = lookup_attribute ("OBJC1META", DECL_ATTRIBUTES (decl)); |
| if (meta) |
| return darwin_objc1_section (decl, meta, base_section); |
| meta = lookup_attribute ("OBJC1METG", DECL_ATTRIBUTES (decl)); |
| if (meta) |
| return base_section; /* GNU runtime is happy with it all in one pot. */ |
| } |
| |
| /* b) Constant string objects. */ |
| if (TREE_CODE (decl) == CONSTRUCTOR |
| && TREE_TYPE (decl) |
| && TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE |
| && TYPE_NAME (TREE_TYPE (decl))) |
| { |
| tree name = TYPE_NAME (TREE_TYPE (decl)); |
| if (TREE_CODE (name) == TYPE_DECL) |
| name = DECL_NAME (name); |
| |
| if (!strcmp (IDENTIFIER_POINTER (name), "__builtin_ObjCString")) |
| { |
| if (flag_next_runtime) |
| { |
| if (flag_objc_abi == 2) |
| return darwin_sections[objc2_constant_string_object_section]; |
| else |
| return darwin_sections[objc_constant_string_object_section]; |
| } |
| else |
| return darwin_sections[objc_string_object_section]; |
| } |
| else if (!strcmp (IDENTIFIER_POINTER (name), "__builtin_CFString")) |
| return darwin_sections[cfstring_constant_object_section]; |
| else |
| return base_section; |
| } |
| else if (flag_next_runtime |
| && VAR_P (decl) |
| && DECL_NAME (decl) |
| && TREE_CODE (DECL_NAME (decl)) == IDENTIFIER_NODE |
| && IDENTIFIER_POINTER (DECL_NAME (decl)) |
| && startswith (IDENTIFIER_POINTER (DECL_NAME (decl)), "_OBJC_")) |
| /* c) legacy meta-data selection was deprecated at 4.6, removed now. */ |
| gcc_unreachable (); |
| |
| return base_section; |
| } |
| |
| /* This can be called with address expressions as "rtx". |
| They must go in "const". */ |
| |
| section * |
| machopic_select_rtx_section (machine_mode mode, rtx x, |
| unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED) |
| { |
| if (known_eq (GET_MODE_SIZE (mode), 8) |
| && (GET_CODE (x) == CONST_INT |
| || GET_CODE (x) == CONST_WIDE_INT |
| || GET_CODE (x) == CONST_DOUBLE)) |
| return darwin_sections[literal8_section]; |
| else if (known_eq (GET_MODE_SIZE (mode), 4) |
| && (GET_CODE (x) == CONST_INT |
| || GET_CODE (x) == CONST_WIDE_INT |
| || GET_CODE (x) == CONST_DOUBLE)) |
| return darwin_sections[literal4_section]; |
| else if (HAVE_GAS_LITERAL16 |
| && TARGET_64BIT |
| && known_eq (GET_MODE_SIZE (mode), 16) |
| && (GET_CODE (x) == CONST_INT |
| || GET_CODE (x) == CONST_WIDE_INT |
| || GET_CODE (x) == CONST_DOUBLE |
| || GET_CODE (x) == CONST_VECTOR)) |
| return darwin_sections[literal16_section]; |
| else if (MACHOPIC_INDIRECT |
| && (GET_CODE (x) == SYMBOL_REF |
| || GET_CODE (x) == CONST |
| || GET_CODE (x) == LABEL_REF)) |
| return darwin_sections[const_data_section]; |
| else |
| return darwin_sections[const_section]; |
| } |
| |
| void |
| machopic_asm_out_constructor (rtx symbol, int priority ATTRIBUTE_UNUSED) |
| { |
| cdtor_record new_elt = {symbol, priority, vec_safe_length (ctors)}; |
| |
| vec_safe_push (ctors, new_elt); |
| |
| if (! MACHOPIC_INDIRECT) |
| fprintf (asm_out_file, ".reference .constructors_used\n"); |
| } |
| |
| void |
| machopic_asm_out_destructor (rtx symbol, int priority ATTRIBUTE_UNUSED) |
| { |
| cdtor_record new_elt = {symbol, priority, vec_safe_length (dtors)}; |
| |
| vec_safe_push (dtors, new_elt); |
| |
| if (! MACHOPIC_INDIRECT) |
| fprintf (asm_out_file, ".reference .destructors_used\n"); |
| } |
| |
| static int |
| sort_cdtor_records (const void * a, const void * b) |
| { |
| const cdtor_record *cda = (const cdtor_record *)a; |
| const cdtor_record *cdb = (const cdtor_record *)b; |
| if (cda->priority > cdb->priority) |
| return 1; |
| if (cda->priority < cdb->priority) |
| return -1; |
| if (cda->position > cdb->position) |
| return 1; |
| if (cda->position < cdb->position) |
| return -1; |
| return 0; |
| } |
| |
| static void |
| finalize_ctors () |
| { |
| unsigned int i; |
| cdtor_record *elt; |
| |
| if (MACHOPIC_INDIRECT) |
| switch_to_section (darwin_sections[mod_init_section]); |
| else |
| switch_to_section (darwin_sections[constructor_section]); |
| |
| /* Where needed, provide a linker-visible section-start symbol so that we |
| have stable output between debug and non-debug. */ |
| if (ld_init_term_start_labels) |
| fputs (MACHOPIC_INDIRECT ? "_Mod.init:\n" : "_CTOR.sect:\n", asm_out_file); |
| |
| if (vec_safe_length (ctors) > 1) |
| ctors->qsort (sort_cdtor_records); |
| FOR_EACH_VEC_SAFE_ELT (ctors, i, elt) |
| { |
| assemble_align (POINTER_SIZE); |
| assemble_integer (elt->symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1); |
| } |
| } |
| |
| static void |
| finalize_dtors () |
| { |
| unsigned int i; |
| cdtor_record *elt; |
| |
| if (MACHOPIC_INDIRECT) |
| switch_to_section (darwin_sections[mod_term_section]); |
| else |
| switch_to_section (darwin_sections[destructor_section]); |
| |
| /* Where needed, provide a linker-visible section-start symbol so that we |
| have stable output between debug and non-debug. */ |
| if (ld_init_term_start_labels) |
| fputs (MACHOPIC_INDIRECT ? "_Mod.term:\n" : "_DTOR.sect:\n", asm_out_file); |
| |
| if (vec_safe_length (dtors) > 1) |
| dtors->qsort (sort_cdtor_records); |
| FOR_EACH_VEC_SAFE_ELT (dtors, i, elt) |
| { |
| assemble_align (POINTER_SIZE); |
| assemble_integer (elt->symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1); |
| } |
| } |
| |
| void |
| darwin_globalize_label (FILE *stream, const char *name) |
| { |
| if (!startswith (name, "_OBJC_")) |
| default_globalize_label (stream, name); |
| /* We have some Objective C cases that need to be global, but only on newer |
| OS versions. */ |
| if (flag_objc_abi < 2 || flag_next_runtime < 100700) |
| return; |
| if (startswith (name+6, "LabelPro")) |
| default_globalize_label (stream, name); |
| if (startswith (name+6, "Protocol_")) |
| default_globalize_label (stream, name); |
| } |
| |
| /* This routine returns non-zero if 'name' starts with the special objective-c |
| anonymous file-scope static name. It accommodates c++'s mangling of such |
| symbols (in this case the symbols will have form _ZL{d}*_OBJC_* d=digit). */ |
| |
| int |
| darwin_label_is_anonymous_local_objc_name (const char *name) |
| { |
| const unsigned char *p = (const unsigned char *) name; |
| if (*p != '_') |
| return 0; |
| if (p[1] == 'Z' && p[2] == 'L') |
| { |
| p += 3; |
| while (*p >= '0' && *p <= '9') |
| p++; |
| } |
| if (!startswith ((const char *)p, "_OBJC_")) |
| return false; |
| |
| /* We need some of the objective c meta-data symbols to be visible to the |
| linker (when the target OS version is newer). FIXME: this is horrible, |
| we need a better mechanism. */ |
| |
| if (flag_objc_abi < 2 || flag_next_runtime < 100700) |
| return true; |
| |
| p += 6; |
| if (startswith ((const char *)p, "ClassRef")) |
| return false; |
| else if (startswith ((const char *)p, "SelRef")) |
| return false; |
| else if (startswith ((const char *)p, "Category")) |
| { |
| if (p[8] == '_' || p[8] == 'I' || p[8] == 'P' || p[8] == 'C' ) |
| return false; |
| return true; |
| } |
| else if (startswith ((const char *)p, "ClassMethods")) |
| return false; |
| else if (startswith ((const char *)p, "Instance")) |
| { |
| if (p[8] == 'I' || p[8] == 'M') |
| return false; |
| return true; |
| } |
| else if (startswith ((const char *)p, "CLASS_RO")) |
| return false; |
| else if (startswith ((const char *)p, "METACLASS_RO")) |
| return false; |
| else if (startswith ((const char *)p, "Protocol")) |
| { |
| if (p[8] == '_' || p[8] == 'I' || p[8] == 'P' |
| || p[8] == 'M' || p[8] == 'C' || p[8] == 'O') |
| return false; |
| return true; |
| } |
| else if (startswith ((const char *)p, "LabelPro")) |
| return false; |
| return true; |
| } |
| |
| /* LTO support for Mach-O. |
| |
| This version uses three mach-o sections to encapsulate the (unlimited |
| number of) lto sections. |
| |
| __GNU_LTO, __lto_sections contains the concatented GNU LTO section data. |
| __GNU_LTO, __section_names contains the GNU LTO section names. |
| __GNU_LTO, __section_index contains an array of values that index these. |
| |
| Indexed thus: |
| <section offset from the start of __GNU_LTO, __lto_sections>, |
| <section length> |
| <name offset from the start of __GNU_LTO, __section_names, |
| <name length>. |
| |
| At present, for both m32 and m64 mach-o files each of these fields is |
| represented by a uint32_t. This is because, AFAICT, a mach-o object |
| cannot exceed 4Gb because the section_64 offset field (see below) is 32bits. |
| |
| uint32_t offset; |
| "offset An integer specifying the offset to this section in the file." */ |
| |
| /* Count lto section numbers. */ |
| static unsigned int lto_section_num = 0; |
| |
| /* A vector of information about LTO sections, at present, we only have |
| the name. TODO: see if we can get the data length somehow. */ |
| typedef struct GTY (()) darwin_lto_section_e { |
| const char *sectname; |
| } darwin_lto_section_e ; |
| |
| static GTY (()) vec<darwin_lto_section_e, va_gc> *lto_section_names; |
| |
| /* Section wrapper scheme (used here to wrap the unlimited number of LTO |
| sections into three Mach-O ones). |
| NOTE: These names MUST be kept in sync with those in |
| libiberty/simple-object-mach-o. */ |
| #define LTO_SECTS_SECTION "__wrapper_sects" |
| #define LTO_NAMES_SECTION "__wrapper_names" |
| #define LTO_INDEX_SECTION "__wrapper_index" |
| |
| /* File to temporarily store LTO data. This is appended to asm_out_file |
| in darwin_end_file. */ |
| static FILE *lto_asm_out_file, *saved_asm_out_file; |
| static char *lto_asm_out_name; |
| static enum debug_info_levels saved_debug_info_level; |
| |
| /* Prepare asm_out_file for LTO output. For darwin, this means hiding |
| asm_out_file and switching to an alternative output file. */ |
| void |
| darwin_asm_lto_start (void) |
| { |
| gcc_assert (! saved_asm_out_file); |
| saved_asm_out_file = asm_out_file; |
| saved_debug_info_level = debug_info_level; |
| debug_info_level = DINFO_LEVEL_NONE; |
| if (! lto_asm_out_name) |
| lto_asm_out_name = make_temp_file (".lto.s"); |
| lto_asm_out_file = fopen (lto_asm_out_name, "a"); |
| if (lto_asm_out_file == NULL) |
| fatal_error (input_location, |
| "failed to open temporary file %s for LTO output", |
| lto_asm_out_name); |
| asm_out_file = lto_asm_out_file; |
| } |
| |
| /* Restore asm_out_file. */ |
| void |
| darwin_asm_lto_end (void) |
| { |
| gcc_assert (saved_asm_out_file); |
| fclose (lto_asm_out_file); |
| asm_out_file = saved_asm_out_file; |
| saved_asm_out_file = NULL; |
| debug_info_level = saved_debug_info_level; |
| } |
| |
| static void |
| darwin_asm_dwarf_section (const char *name, unsigned int flags, |
| tree decl, bool is_for_lto); |
| |
| /* Called for the TARGET_ASM_NAMED_SECTION hook. */ |
| |
| void |
| darwin_asm_named_section (const char *name, |
| unsigned int flags, |
| tree decl ATTRIBUTE_UNUSED) |
| { |
| /* LTO sections go in a special section that encapsulates the (unlimited) |
| number of GNU LTO sections within a single mach-o one. */ |
| if (startswith (name, LTO_SECTION_NAME_PREFIX)) |
| { |
| darwin_lto_section_e e; |
| /* We expect certain flags to be set... */ |
| gcc_assert ((flags & (SECTION_DEBUG | SECTION_NAMED)) |
| == (SECTION_DEBUG | SECTION_NAMED)); |
| |
| /* Switch to our combined section. */ |
| fprintf (asm_out_file, "\t.section %s,%s,regular,debug\n", |
| LTO_SEGMENT_NAME, LTO_SECTS_SECTION); |
| /* Output a label for the start of this sub-section. */ |
| fprintf (asm_out_file, "L_GNU_LTO%d:\t;# %s\n", |
| lto_section_num, name); |
| /* We have to jump through hoops to get the values of the intra-section |
| offsets... */ |
| fprintf (asm_out_file, "\t.set L$gnu$lto$offs%d,L_GNU_LTO%d-L_GNU_LTO0\n", |
| lto_section_num, lto_section_num); |
| fprintf (asm_out_file, |
| "\t.set L$gnu$lto$size%d,L_GNU_LTO%d-L_GNU_LTO%d\n", |
| lto_section_num, lto_section_num+1, lto_section_num); |
| lto_section_num++; |
| e.sectname = xstrdup (name); |
| /* Keep the names, we'll need to make a table later. |
| TODO: check that we do not revisit sections, that would break |
| the assumption of how this is done. */ |
| if (lto_section_names == NULL) |
| vec_alloc (lto_section_names, 16); |
| vec_safe_push (lto_section_names, e); |
| } |
| else if (startswith (name, "__DWARF,")) |
| darwin_asm_dwarf_section (name, flags, decl, false); |
| else if (startswith (name, "__GNU_DWARF_LTO,")) |
| darwin_asm_dwarf_section (name, flags, decl, true); |
| else |
| fprintf (asm_out_file, "\t.section %s\n", name); |
| } |
| |
| void |
| darwin_unique_section (tree decl ATTRIBUTE_UNUSED, int reloc ATTRIBUTE_UNUSED) |
| { |
| /* Darwin does not use unique sections. */ |
| } |
| |
| /* Handle __attribute__ ((apple_kext_compatibility)). |
| This only applies to darwin kexts for 2.95 compatibility -- it shrinks the |
| vtable for classes with this attribute (and their descendants) by not |
| outputting the new 3.0 nondeleting destructor. This means that such |
| objects CANNOT be allocated on the stack or as globals UNLESS they have |
| a completely empty `operator delete'. |
| Luckily, this fits in with the Darwin kext model. |
| |
| This attribute also disables gcc3's potential overlaying of derived |
| class data members on the padding at the end of the base class. */ |
| |
| tree |
| darwin_handle_kext_attribute (tree *node, tree name, |
| tree args ATTRIBUTE_UNUSED, |
| int flags ATTRIBUTE_UNUSED, |
| bool *no_add_attrs) |
| { |
| /* APPLE KEXT stuff -- only applies with pure static C++ code. */ |
| if (! TARGET_KEXTABI) |
| { |
| warning (0, "%qE 2.95 vtable-compatibility attribute applies " |
| "only when compiling a kext", name); |
| |
| *no_add_attrs = true; |
| } |
| else if (TREE_CODE (*node) != RECORD_TYPE) |
| { |
| warning (0, "%qE 2.95 vtable-compatibility attribute applies " |
| "only to C++ classes", name); |
| |
| *no_add_attrs = true; |
| } |
| |
| return NULL_TREE; |
| } |
| |
| /* Handle a "weak_import" attribute; arguments as in |
| struct attribute_spec.handler. */ |
| |
| tree |
| darwin_handle_weak_import_attribute (tree *node, tree name, |
| tree ARG_UNUSED (args), |
| int ARG_UNUSED (flags), |
| bool * no_add_attrs) |
| { |
| if (TREE_CODE (*node) != FUNCTION_DECL && TREE_CODE (*node) != VAR_DECL) |
| { |
| warning (OPT_Wattributes, "%qE attribute ignored", |
| name); |
| *no_add_attrs = true; |
| } |
| else |
| declare_weak (*node); |
| |
| return NULL_TREE; |
| } |
| |
| /* Emit a label for an FDE, making it global and/or weak if appropriate. |
| The third parameter is nonzero if this is for exception handling. |
| The fourth parameter is nonzero if this is just a placeholder for an |
| FDE that we are omitting. */ |
| |
| void |
| darwin_emit_unwind_label (FILE *file, tree decl, int for_eh, int empty) |
| { |
| char *lab ; |
| char buf[32]; |
| static int invok_count = 0; |
| static tree last_fun_decl = NULL_TREE; |
| |
| /* Modern linkers can produce distinct FDEs without compiler support. */ |
| if (! for_eh || ! ld_needs_eh_markers) |
| return; |
| |
| /* FIXME: This only works when the eh for all sections of a function are |
| emitted at the same time. If that changes, we would need to use a lookup |
| table of some form to determine what to do. Also, we should emit the |
| unadorned label for the partition containing the public label for a |
| function. This is of limited use, probably, since we do not currently |
| enable partitioning. */ |
| strcpy (buf, ".eh"); |
| if (decl && TREE_CODE (decl) == FUNCTION_DECL) |
| { |
| if (decl == last_fun_decl) |
| { |
| invok_count++; |
| snprintf (buf, 31, "$$part$$%d.eh", invok_count); |
| } |
| else |
| { |
| last_fun_decl = decl; |
| invok_count = 0; |
| } |
| } |
| |
| lab = concat (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)), buf, NULL); |
| |
| if (TREE_PUBLIC (decl)) |
| { |
| targetm.asm_out.globalize_label (file, lab); |
| if (DECL_VISIBILITY (decl) == VISIBILITY_HIDDEN) |
| { |
| fputs ("\t.private_extern ", file); |
| assemble_name (file, lab); |
| fputc ('\n', file); |
| } |
| } |
| |
| if (DECL_WEAK (decl)) |
| { |
| fputs ("\t.weak_definition ", file); |
| assemble_name (file, lab); |
| fputc ('\n', file); |
| } |
| |
| assemble_name (file, lab); |
| if (empty) |
| { |
| fputs (" = 0\n", file); |
| |
| /* Mark the absolute .eh and .eh1 style labels as needed to |
| ensure that we don't dead code strip them and keep such |
| labels from another instantiation point until we can fix this |
| properly with group comdat support. */ |
| darwin_mark_decl_preserved (lab); |
| } |
| else |
| fputs (":\n", file); |
| |
| free (lab); |
| } |
| |
| static GTY(()) unsigned long except_table_label_num; |
| |
| void |
| darwin_emit_except_table_label (FILE *file) |
| { |
| char section_start_label[30]; |
| |
| ASM_GENERATE_INTERNAL_LABEL (section_start_label, "GCC_except_table", |
| except_table_label_num++); |
| ASM_OUTPUT_LABEL (file, section_start_label); |
| } |
| |
| rtx |
| darwin_make_eh_symbol_indirect (rtx orig, bool ARG_UNUSED (pubvis)) |
| { |
| if (DARWIN_PPC == 0 && TARGET_64BIT) |
| return orig; |
| |
| return gen_rtx_SYMBOL_REF (Pmode, |
| machopic_indirection_name (orig, |
| /*stub_p=*/false)); |
| } |
| |
| /* The unwinders in earlier Darwin versions are based on an old version |
| of libgcc_s and need current frame address stateto be reset after a |
| DW_CFA_restore_state recovers the register values. */ |
| |
| bool |
| darwin_should_restore_cfa_state (void) |
| { |
| return generating_for_darwin_version <= 10; |
| } |
| |
| /* Return, and mark as used, the name of the stub for the mcount function. |
| Currently, this is only called by X86 code in the expansion of the |
| FUNCTION_PROFILER macro, when stubs are enabled. */ |
| |
| const char* |
| machopic_mcount_stub_name (void) |
| { |
| rtx symbol = gen_rtx_SYMBOL_REF (Pmode, "*mcount"); |
| const char *name = machopic_indirection_name (symbol, /*stub_p=*/true); |
| machopic_validate_stub_or_non_lazy_ptr (name); |
| return name; |
| } |
| |
| /* Generate a PC-relative reference to a Mach-O non-lazy-symbol. */ |
| |
| void |
| darwin_non_lazy_pcrel (FILE *file, rtx addr) |
| { |
| const char *nlp_name; |
| |
| gcc_assert (GET_CODE (addr) == SYMBOL_REF); |
| |
| nlp_name = machopic_indirection_name (addr, /*stub_p=*/false); |
| fputs ("\t.long\t", file); |
| ASM_OUTPUT_LABELREF (file, nlp_name); |
| fputs ("-.", file); |
| } |
| |
| /* If this is uncommented, details of each allocation will be printed |
| in the asm right before the actual code. WARNING - this will cause some |
| test-suite fails (since the printout will contain items that some tests |
| are not expecting) -- so don't leave it on by default (it bloats the |
| asm too). */ |
| /*#define DEBUG_DARWIN_MEM_ALLOCATORS*/ |
| |
| /* The first two of these routines are ostensibly just intended to put |
| names into the asm. However, they are both hijacked in order to ensure |
| that zero-sized items do not make their way into the output. Consequently, |
| we also need to make these participate in provisions for dealing with |
| such items in section anchors. */ |
| |
| /* The implementation of ASM_DECLARE_OBJECT_NAME. */ |
| /* The RTTI data (e.g., __ti4name) is common and public (and static), |
| but it does need to be referenced via indirect PIC data pointers. |
| The machopic_define_symbol calls are telling the machopic subsystem |
| that the name *is* defined in this module, so it doesn't need to |
| make them indirect. */ |
| void |
| darwin_asm_declare_object_name (FILE *file, |
| const char *nam, tree decl) |
| { |
| const char *xname = nam; |
| unsigned HOST_WIDE_INT size; |
| bool local_def, weak; |
| |
| weak = (DECL_P (decl) |
| && DECL_WEAK (decl) |
| && !lookup_attribute ("weak_import", |
| DECL_ATTRIBUTES (decl))); |
| |
| local_def = DECL_INITIAL (decl) || (TREE_STATIC (decl) |
| && (!DECL_COMMON (decl) |
| || !TREE_PUBLIC (decl))); |
| |
| if (GET_CODE (XEXP (DECL_RTL (decl), 0)) != SYMBOL_REF) |
| xname = IDENTIFIER_POINTER (DECL_NAME (decl)); |
| |
| if (local_def) |
| { |
| (* targetm.encode_section_info) (decl, DECL_RTL (decl), false); |
| if (!weak) |
| machopic_define_symbol (DECL_RTL (decl)); |
| } |
| |
| size = tree_to_uhwi (DECL_SIZE_UNIT (decl)); |
| |
| #ifdef DEBUG_DARWIN_MEM_ALLOCATORS |
| fprintf (file, "# dadon: %s %s (%llu, %u) local %d weak %d" |
| " stat %d com %d pub %d t-const %d t-ro %d init %lx\n", |
| xname, (TREE_CODE (decl) == VAR_DECL?"var":"const"), |
| (unsigned long long)size, DECL_ALIGN (decl), local_def, |
| DECL_WEAK (decl), TREE_STATIC (decl), DECL_COMMON (decl), |
| TREE_PUBLIC (decl), TREE_CONSTANT (decl), TREE_READONLY (decl), |
| (unsigned long)DECL_INITIAL (decl)); |
| #endif |
| |
| /* Darwin needs help to support local zero-sized objects. |
| They must be made at least one byte, and the section containing must be |
| marked as unsuitable for section-anchors (see storage allocators below). |
| |
| For non-zero objects this output is handled by varasm.c. |
| */ |
| if (!size) |
| { |
| unsigned int l2align = 0; |
| |
| /* The align must be honored, even for zero-sized. */ |
| if (DECL_ALIGN (decl)) |
| { |
| l2align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT); |
| fprintf (file, "\t.align\t%u\n", l2align); |
| } |
| |
| ASM_OUTPUT_LABEL (file, xname); |
| size = 1; |
| fprintf (file, "\t.space\t" HOST_WIDE_INT_PRINT_UNSIGNED"\n", size); |
| |
| /* Check that we've correctly picked up the zero-sized item and placed it |
| properly. */ |
| gcc_assert ((!DARWIN_SECTION_ANCHORS || !flag_section_anchors) |
| || (in_section |
| && (in_section->common.flags & SECTION_NO_ANCHOR))); |
| } |
| else |
| ASM_OUTPUT_LABEL (file, xname); |
| } |
| |
| /* The implementation of ASM_DECLARE_CONSTANT_NAME. */ |
| void |
| darwin_asm_declare_constant_name (FILE *file, const char *name, |
| const_tree exp ATTRIBUTE_UNUSED, |
| HOST_WIDE_INT size) |
| { |
| assemble_label (file, name); |
| /* As for other items, we need at least one byte. */ |
| if (!size) |
| { |
| fputs ("\t.space\t1\n", file); |
| /* Check that we've correctly picked up the zero-sized item and placed it |
| properly. */ |
| gcc_assert ((!DARWIN_SECTION_ANCHORS || !flag_section_anchors) |
| || (in_section |
| && (in_section->common.flags & SECTION_NO_ANCHOR))); |
| } |
| } |
| |
| /* Darwin storage allocators. |
| |
| Zerofill sections are desirable for large blank data since, otherwise, these |
| data bloat objects (PR33210). |
| |
| However, section anchors don't work in .zerofill sections (one cannot switch |
| to a zerofill section). Ergo, for Darwin targets using section anchors we need |
| to put (at least some) data into 'normal' switchable sections. |
| |
| Here we set a relatively arbitrary value for the size of an object to trigger |
| zerofill when section anchors are enabled (anything bigger than a page for |
| current Darwin implementations). FIXME: there ought to be some objective way |
| to make this choice. |
| |
| When section anchor are off this is ignored anyway. */ |
| |
| #define BYTES_ZFILL 4096 |
| |
| /* Emit a chunk of data for items coalesced by the linker. */ |
| static void |
| darwin_emit_weak_or_comdat (FILE *fp, tree decl, const char *name, |
| unsigned HOST_WIDE_INT size, |
| bool use_coal, |
| unsigned int align) |
| { |
| /* Since the sections used here are coalesced, they will not be eligible |
| for section anchors, and therefore we don't need to break that out. |
| CHECKME: for modern linker on PowerPC. */ |
| if (TREE_READONLY (decl) || TREE_CONSTANT (decl)) |
| switch_to_section (use_coal ? darwin_sections[const_data_coal_section] |
| : darwin_sections[const_data_section]); |
| else |
| switch_to_section (use_coal ? darwin_sections[data_coal_section] |
| : data_section); |
| |
| /* To be consistent, we'll allow darwin_asm_declare_object_name to assemble |
| the align info for zero-sized items... but do it here otherwise. */ |
| if (size && align) |
| fprintf (fp, "\t.align\t%d\n", floor_log2 (align / BITS_PER_UNIT)); |
| |
| if (TREE_PUBLIC (decl)) |
| darwin_globalize_label (fp, name); |
| |
| /* ... and we let it deal with outputting one byte of zero for them too. */ |
| darwin_asm_declare_object_name (fp, name, decl); |
| if (size) |
| assemble_zeros (size); |
| } |
| |
| /* Emit a chunk of data for ObjC meta-data that got placed in BSS erroneously. */ |
| static void |
| darwin_emit_objc_zeroed (FILE *fp, tree decl, const char *name, |
| unsigned HOST_WIDE_INT size, |
| unsigned int align, tree meta) |
| { |
| section *ocs = data_section; |
| |
| if (TREE_PURPOSE (meta) == get_identifier("OBJC2META")) |
| ocs = darwin_objc2_section (decl, meta, ocs); |
| else |
| ocs = darwin_objc1_section (decl, meta, ocs); |
| |
| switch_to_section (ocs); |
| |
| /* We shall declare that zero-sized meta-data are not valid (yet). */ |
| gcc_assert (size); |
| fprintf (fp, "\t.align\t%d\n", floor_log2 (align / BITS_PER_UNIT)); |
| |
| /* ... and we let it deal with outputting one byte of zero for them too. */ |
| darwin_asm_declare_object_name (fp, name, decl); |
| assemble_zeros (size); |
| } |
| |
| /* This routine emits 'local' storage: |
| |
| When Section Anchors are off this routine emits .zerofill commands in |
| sections named for their alignment. |
| |
| When Section Anchors are on, smaller (non-zero-sized) items are placed in |
| the .static_data section so that the section anchoring system can see them. |
| Larger items are still placed in .zerofill sections, addressing PR33210. |
| The routine has no checking - it is all assumed to be done by the caller. |
| */ |
| static void |
| darwin_emit_local_bss (FILE *fp, tree decl, const char *name, |
| unsigned HOST_WIDE_INT size, |
| unsigned int l2align) |
| { |
| if (DARWIN_SECTION_ANCHORS && flag_section_anchors && size < BYTES_ZFILL) |
| { |
| /* Put smaller objects in _static_data, where the section anchors system |
| can get them. |
| However, if they are zero-sized punt them to yet a different section |
| (that is not allowed to participate in anchoring). */ |
| if (!size) |
| { |
| fputs ("\t.section\t__DATA,__zobj_bss\n", fp); |
| in_section = darwin_sections[zobj_bss_section]; |
| size = 1; |
| } |
| else |
| { |
| fputs ("\t.static_data\n", fp); |
| in_section = darwin_sections[static_data_section]; |
| } |
| |
| if (l2align) |
| fprintf (fp, "\t.align\t%u\n", l2align); |
| |
| assemble_name (fp, name); |
| fprintf (fp, ":\n\t.space\t" HOST_WIDE_INT_PRINT_UNSIGNED"\n", size); |
| } |
| else |
| { |
| /* When we are on a non-section anchor target (or not using section |
| anchors, we can get zero-sized items here. However, all we need to |
| do is to bump them to one byte and the section alignment will take |
| care of the rest. */ |
| char secnam[64]; |
| snprintf (secnam, 64, "__DATA,__bss"); |
| unsigned int flags = SECTION_BSS|SECTION_WRITE|SECTION_NO_ANCHOR; |
| in_section = get_section (secnam, flags, NULL); |
| fprintf (fp, "\t.zerofill %s,", secnam); |
| assemble_name (fp, name); |
| if (!size) |
| size = 1; |
| |
| if (l2align) |
| fprintf (fp, "," HOST_WIDE_INT_PRINT_UNSIGNED",%u\n", |
| size, (unsigned) l2align); |
| else |
| fprintf (fp, "," HOST_WIDE_INT_PRINT_UNSIGNED",0\n", size); |
| } |
| |
| (*targetm.encode_section_info) (decl, DECL_RTL (decl), false); |
| /* This is defined as a file-scope var, so we know to notify machopic. */ |
| machopic_define_symbol (DECL_RTL (decl)); |
| } |
| |
| /* Emit a chunk of common. */ |
| static void |
| darwin_emit_common (FILE *fp, const char *name, |
| unsigned HOST_WIDE_INT size, unsigned int align) |
| { |
| unsigned HOST_WIDE_INT rounded; |
| unsigned int l2align; |
| |
| /* Earlier systems complain if the alignment exceeds the page size. |
| The magic number is 4096 * 8 - hard-coded for legacy systems. */ |
| if (!emit_aligned_common && (align > 32768UL)) |
| align = 4096UL; /* In units. */ |
| else |
| align /= BITS_PER_UNIT; |
| |
| /* Make sure we have a meaningful align. */ |
| if (!align) |
| align = 1; |
| |
| /* For earlier toolchains, we need to emit the var as a rounded size to |
| tell ld the alignment. */ |
| if (size < align) |
| rounded = align; |
| else |
| rounded = (size + (align-1)) & ~(align-1); |
| |
| l2align = floor_log2 (align); |
| gcc_assert (l2align <= L2_MAX_OFILE_ALIGNMENT); |
| |
| in_section = comm_section; |
| /* We mustn't allow multiple public symbols to share an address when using |
| the normal OSX toolchain. */ |
| if (!size) |
| { |
| /* Put at least one byte. */ |
| size = 1; |
| /* This section can no longer participate in section anchoring. */ |
| comm_section->common.flags |= SECTION_NO_ANCHOR; |
| } |
| |
| fputs ("\t.comm\t", fp); |
| assemble_name (fp, name); |
| fprintf (fp, "," HOST_WIDE_INT_PRINT_UNSIGNED, |
| emit_aligned_common?size:rounded); |
| if (l2align && emit_aligned_common) |
| fprintf (fp, ",%u", l2align); |
| fputs ("\n", fp); |
| } |
| |
| /* Output a var which is all zero - into aligned BSS sections, common, lcomm |
| or coalescable data sections (for weak or comdat) as appropriate. */ |
| |
| void |
| darwin_output_aligned_bss (FILE *fp, tree decl, const char *name, |
| unsigned HOST_WIDE_INT size, unsigned int align) |
| { |
| unsigned int l2align; |
| bool one, pub, weak; |
| tree meta; |
| |
| pub = TREE_PUBLIC (decl); |
| one = DECL_ONE_ONLY (decl); |
| weak = (DECL_P (decl) |
| && DECL_WEAK (decl) |
| && !lookup_attribute ("weak_import", |
| DECL_ATTRIBUTES (decl))); |
| |
| #ifdef DEBUG_DARWIN_MEM_ALLOCATORS |
| fprintf (fp, "# albss: %s (%lld,%d) ro %d cst %d stat %d com %d" |
| " pub %d weak %d one %d init %lx\n", |
| name, (long long)size, (int)align, TREE_READONLY (decl), |
| TREE_CONSTANT (decl), TREE_STATIC (decl), DECL_COMMON (decl), |
| pub, weak, one, (unsigned long)DECL_INITIAL (decl)); |
| #endif |
| |
| /* ObjC metadata can get put in BSS because varasm.c decides it's BSS |
| before the target has a chance to comment. */ |
| if ((meta = is_objc_metadata (decl))) |
| { |
| darwin_emit_objc_zeroed (fp, decl, name, size, DECL_ALIGN (decl), meta); |
| return; |
| } |
| |
| /* Check that any initializer is valid. */ |
| gcc_assert ((DECL_INITIAL (decl) == NULL) |
| || (DECL_INITIAL (decl) == error_mark_node) |
| || initializer_zerop (DECL_INITIAL (decl))); |
| |
| gcc_assert (DECL_SECTION_NAME (decl) == NULL); |
| gcc_assert (!DECL_COMMON (decl)); |
| |
| /* Pick up the correct alignment. */ |
| if (!size || !align) |
| align = DECL_ALIGN (decl); |
| |
| l2align = floor_log2 (align / BITS_PER_UNIT); |
| gcc_assert (l2align <= L2_MAX_OFILE_ALIGNMENT); |
| |
| last_assemble_variable_decl = decl; |
| |
| /* We would rather not have to check this here - but it seems that we might |
| be passed a decl that should be in coalesced space. */ |
| if (one || weak) |
| { |
| /* Weak or COMDAT objects are put in mergeable sections. */ |
| darwin_emit_weak_or_comdat (fp, decl, name, size, |
| ld_uses_coal_sects, DECL_ALIGN (decl)); |
| return; |
| } |
| |
| /* If this is not public, then emit according to local rules. */ |
| if (!pub) |
| { |
| darwin_emit_local_bss (fp, decl, name, size, l2align); |
| return; |
| } |
| |
| /* So we have a public symbol. */ |
| if (DARWIN_SECTION_ANCHORS && flag_section_anchors && size < BYTES_ZFILL) |
| { |
| /* Put smaller objects in data, where the section anchors system can get |
| them. However, if they are zero-sized punt them to yet a different |
| section (that is not allowed to participate in anchoring). */ |
| if (!size) |
| { |
| fputs ("\t.section\t__DATA,__zobj_data\n", fp); |
| in_section = darwin_sections[zobj_data_section]; |
| size = 1; |
| } |
| else |
| { |
| fputs ("\t.data\n", fp); |
| in_section = data_section; |
| } |
| |
| if (l2align) |
| fprintf (fp, "\t.align\t%u\n", l2align); |
| |
| assemble_name (fp, name); |
| fprintf (fp, ":\n\t.space\t" HOST_WIDE_INT_PRINT_UNSIGNED"\n", size); |
| } |
| else |
| { |
| /* Section anchors not in use. */ |
| unsigned int flags = SECTION_BSS|SECTION_WRITE|SECTION_NO_ANCHOR; |
| char secnam[64]; |
| snprintf (secnam, 64, "__DATA,__common"); |
| in_section = get_section (secnam, flags, NULL); |
| fprintf (fp, "\t.zerofill %s,", secnam); |
| assemble_name (fp, name); |
| if (!size) |
| size = 1; |
| |
| if (l2align) |
| fprintf (fp, "," HOST_WIDE_INT_PRINT_UNSIGNED",%u\n", size, l2align); |
| else |
| fprintf (fp, "," HOST_WIDE_INT_PRINT_UNSIGNED",0\n", size); |
| } |
| (* targetm.encode_section_info) (decl, DECL_RTL (decl), false); |
| } |
| |
| /* Output a chunk of common, with alignment specified (where the target |
| supports this). */ |
| void |
| darwin_asm_output_aligned_decl_common (FILE *fp, tree decl, const char *name, |
| unsigned HOST_WIDE_INT size, |
| unsigned int align) |
| { |
| unsigned int l2align; |
| bool one, weak; |
| tree meta; |
| |
| /* No corresponding var. */ |
| if (decl==NULL) |
| { |
| #ifdef DEBUG_DARWIN_MEM_ALLOCATORS |
| fprintf (fp, "# adcom: %s (%d,%d) decl=0x0\n", name, (int)size, (int)align); |
| #endif |
| darwin_emit_common (fp, name, size, align); |
| return; |
| } |
| |
| one = DECL_ONE_ONLY (decl); |
| weak = (DECL_P (decl) |
| && DECL_WEAK (decl) |
| && !lookup_attribute ("weak_import", |
| DECL_ATTRIBUTES (decl))); |
| |
| #ifdef DEBUG_DARWIN_MEM_ALLOCATORS |
| fprintf (fp, "# adcom: %s (%lld,%d) ro %d cst %d stat %d com %d pub %d" |
| " weak %d one %d init %lx\n", |
| name, (long long)size, (int)align, TREE_READONLY (decl), |
| TREE_CONSTANT (decl), TREE_STATIC (decl), DECL_COMMON (decl), |
| TREE_PUBLIC (decl), weak, one, (unsigned long)DECL_INITIAL (decl)); |
| #endif |
| |
| /* ObjC metadata can get put in BSS because varasm.c decides it's BSS |
| before the target has a chance to comment. */ |
| if ((meta = is_objc_metadata (decl))) |
| { |
| darwin_emit_objc_zeroed (fp, decl, name, size, DECL_ALIGN (decl), meta); |
| return; |
| } |
| |
| /* We shouldn't be messing with this if the decl has a section name. */ |
| gcc_assert (DECL_SECTION_NAME (decl) == NULL); |
| |
| /* We would rather not have to check this here - but it seems that we might |
| be passed a decl that should be in coalesced space. */ |
| if (one || weak) |
| { |
| /* Weak or COMDAT objects are put in mergable sections. */ |
| darwin_emit_weak_or_comdat (fp, decl, name, size, |
| ld_uses_coal_sects, DECL_ALIGN (decl)); |
| return; |
| } |
| |
| /* We should only get here for DECL_COMMON, with a zero init (and, in |
| principle, only for public symbols too - although we deal with local |
| ones below). */ |
| |
| /* Check the initializer is OK. */ |
| gcc_assert (DECL_COMMON (decl) |
| && ((DECL_INITIAL (decl) == NULL) |
| || (DECL_INITIAL (decl) == error_mark_node) |
| || initializer_zerop (DECL_INITIAL (decl)))); |
| |
| last_assemble_variable_decl = decl; |
| |
| if (!size || !align) |
| align = DECL_ALIGN (decl); |
| |
| l2align = floor_log2 (align / BITS_PER_UNIT); |
| /* Check we aren't asking for more aligment than the platform allows. */ |
| gcc_assert (l2align <= L2_MAX_OFILE_ALIGNMENT); |
| |
| if (TREE_PUBLIC (decl) != 0) |
| darwin_emit_common (fp, name, size, align); |
| else |
| darwin_emit_local_bss (fp, decl, name, size, l2align); |
| } |
| |
| /* Output a chunk of BSS with alignment specfied. */ |
| void |
| darwin_asm_output_aligned_decl_local (FILE *fp, tree decl, const char *name, |
| unsigned HOST_WIDE_INT size, |
| unsigned int align) |
| { |
| unsigned long l2align; |
| bool one, weak; |
| tree meta; |
| |
| one = DECL_ONE_ONLY (decl); |
| weak = (DECL_P (decl) |
| && DECL_WEAK (decl) |
| && !lookup_attribute ("weak_import", |
| DECL_ATTRIBUTES (decl))); |
| |
| #ifdef DEBUG_DARWIN_MEM_ALLOCATORS |
| fprintf (fp, "# adloc: %s (%lld,%d) ro %d cst %d stat %d one %d pub %d" |
| " weak %d init %lx\n", |
| name, (long long)size, (int)align, TREE_READONLY (decl), |
| TREE_CONSTANT (decl), TREE_STATIC (decl), one, TREE_PUBLIC (decl), |
| weak , (unsigned long)DECL_INITIAL (decl)); |
| #endif |
| |
| /* ObjC metadata can get put in BSS because varasm.c decides it's BSS |
| before the target has a chance to comment. */ |
| if ((meta = is_objc_metadata (decl))) |
| { |
| darwin_emit_objc_zeroed (fp, decl, name, size, DECL_ALIGN (decl), meta); |
| return; |
| } |
| |
| /* We shouldn't be messing with this if the decl has a section name. */ |
| gcc_assert (DECL_SECTION_NAME (decl) == NULL); |
| |
| /* We would rather not have to check this here - but it seems that we might |
| be passed a decl that should be in coalesced space. */ |
| if (one || weak) |
| { |
| /* Weak or COMDAT objects are put in mergable sections. */ |
| darwin_emit_weak_or_comdat (fp, decl, name, size, |
| ld_uses_coal_sects, DECL_ALIGN (decl)); |
| return; |
| } |
| |
| /* .. and it should be suitable for placement in local mem. */ |
| gcc_assert(!TREE_PUBLIC (decl) && !DECL_COMMON (decl)); |
| /* .. and any initializer must be all-zero. */ |
| gcc_assert ((DECL_INITIAL (decl) == NULL) |
| || (DECL_INITIAL (decl) == error_mark_node) |
| || initializer_zerop (DECL_INITIAL (decl))); |
| |
| last_assemble_variable_decl = decl; |
| |
| if (!size || !align) |
| align = DECL_ALIGN (decl); |
| |
| l2align = floor_log2 (align / BITS_PER_UNIT); |
| gcc_assert (l2align <= L2_MAX_OFILE_ALIGNMENT); |
| |
| darwin_emit_local_bss (fp, decl, name, size, l2align); |
| } |
| |
| /* Emit an assembler directive to set visibility for a symbol. The |
| only supported visibilities are VISIBILITY_DEFAULT and |
| VISIBILITY_HIDDEN; the latter corresponds to Darwin's "private |
| extern". There is no MACH-O equivalent of ELF's |
| VISIBILITY_INTERNAL or VISIBILITY_PROTECTED. */ |
| |
| void |
| darwin_assemble_visibility (tree decl, int vis) |
| { |
| if (vis == VISIBILITY_DEFAULT) |
| ; |
| else if (vis == VISIBILITY_HIDDEN || vis == VISIBILITY_INTERNAL) |
| { |
| fputs ("\t.private_extern ", asm_out_file); |
| assemble_name (asm_out_file, |
| (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)))); |
| fputs ("\n", asm_out_file); |
| } |
| else |
| warning (OPT_Wattributes, "protected visibility attribute " |
| "not supported in this configuration; ignored"); |
| } |
| |
| /* vec used by darwin_asm_dwarf_section. |
| Maybe a hash tab would be better here - but the intention is that this is |
| a very short list (fewer than 16 items) and each entry should (ideally, |
| eventually) only be presented once. |
| |
| A structure to hold a dwarf debug section used entry. */ |
| |
| typedef struct GTY(()) dwarf_sect_used_entry { |
| const char *name; |
| unsigned count; |
| } |
| dwarf_sect_used_entry; |
| |
| |
| /* A list of used __DWARF sections. */ |
| static GTY (()) vec<dwarf_sect_used_entry, va_gc> *dwarf_sect_names_table; |
| |
| /* This is called when we are asked to assemble a named section and the |
| name begins with __DWARF,. We keep a list of the section names (without |
| the __DWARF, prefix) and use this to emit our required start label on the |
| first switch to each section. */ |
| |
| static void |
| darwin_asm_dwarf_section (const char *name, unsigned int flags, |
| tree ARG_UNUSED (decl), bool is_for_lto) |
| { |
| unsigned i; |
| int namelen, extra = 0; |
| const char *sect, *lto_add = ""; |
| char sname[64]; |
| dwarf_sect_used_entry *ref; |
| bool found = false; |
| |
| gcc_checking_assert ((flags & (SECTION_DEBUG | SECTION_NAMED)) |
| == (SECTION_DEBUG | SECTION_NAMED)); |
| |
| /* We know that the name starts with __DWARF, or __GNU_DAWRF_LTO */ |
| sect = strchr (name, ',') + 1; |
| namelen = strchr (sect, ',') - sect; |
| gcc_checking_assert (namelen); |
| |
| /* The section switch is output as written... */ |
| fprintf (asm_out_file, "\t.section %s\n", name); |
| |
| /* ... but the string we keep to make section start labels needs |
| adjustment for lto cases. */ |
| if (is_for_lto) |
| { |
| lto_add = "_lto"; |
| extra = 4; |
| } |
| |
| snprintf (sname, 64, "%.*s%.*s", namelen, sect, extra, lto_add); |
| namelen += extra; |
| |
| if (dwarf_sect_names_table == NULL) |
| vec_alloc (dwarf_sect_names_table, 16); |
| else |
| for (i = 0; |
| dwarf_sect_names_table->iterate (i, &ref); |
| i++) |
| { |
| if (!ref) |
| break; |
| if (!strcmp (ref->name, sname)) |
| { |
| found = true; |
| ref->count++; |
| break; |
| } |
| } |
| |
| if (!found) |
| { |
| dwarf_sect_used_entry e; |
| fprintf (asm_out_file, "Lsection%.*s:\n", namelen, sname); |
| e.count = 1; |
| e.name = xstrdup (sname); |
| vec_safe_push (dwarf_sect_names_table, e); |
| } |
| } |
| |
| /* Output a difference of two labels that will be an assembly time |
| constant if the two labels are local. (.long lab1-lab2 will be |
| very different if lab1 is at the boundary between two sections; it |
| will be relocated according to the second section, not the first, |
| so one ends up with a difference between labels in different |
| sections, which is bad in the dwarf2 eh context for instance.) */ |
| |
| static int darwin_dwarf_label_counter; |
| |
| void |
| darwin_asm_output_dwarf_delta (FILE *file, int size, |
| const char *lab1, const char *lab2, |
| HOST_WIDE_INT offset) |
| { |
| int islocaldiff = (lab1[0] == '*' && lab1[1] == 'L' |
| && lab2[0] == '*' && lab2[1] == 'L'); |
| const char *directive = (size == 8 ? ".quad" : ".long"); |
| |
| if (islocaldiff) |
| fprintf (file, "\t.set L$set$%d,", darwin_dwarf_label_counter); |
| else |
| fprintf (file, "\t%s\t", directive); |
| |
| assemble_name_raw (file, lab1); |
| fprintf (file, "-"); |
| assemble_name_raw (file, lab2); |
| if (offset != 0) |
| fprintf (file, "+" HOST_WIDE_INT_PRINT_DEC, offset); |
| if (islocaldiff) |
| fprintf (file, "\n\t%s L$set$%d", directive, darwin_dwarf_label_counter++); |
| } |
| |
| /* Output an offset in a DWARF section on Darwin. On Darwin, DWARF section |
| offsets are not represented using relocs in .o files; either the |
| section never leaves the .o file, or the linker or other tool is |
| responsible for parsing the DWARF and updating the offsets. */ |
| |
| void |
| darwin_asm_output_dwarf_offset (FILE *file, int size, const char * lab, |
| HOST_WIDE_INT offset, section *base) |
| { |
| char sname[64]; |
| int namelen, extra = 0; |
| bool is_for_lto; |
| const char *lto_add = ""; |
| |
| gcc_checking_assert (base->common.flags & SECTION_NAMED); |
| is_for_lto = startswith (base->named.name, "__GNU_DWARF_LTO,"); |
| gcc_checking_assert (is_for_lto |
| || startswith (base->named.name, "__DWARF,")); |
| const char *name = strchr (base->named.name, ',') + 1; |
| gcc_checking_assert (name); |
| |
| namelen = strchr (name, ',') - (name); |
| if (is_for_lto) |
| { |
| lto_add = "_lto"; |
| extra = 4; |
| } |
| snprintf (sname, 64, "*Lsection%.*s%.*s", namelen, name, extra, lto_add); |
| darwin_asm_output_dwarf_delta (file, size, lab, sname, offset); |
| } |
| |
| /* Called from the within the TARGET_ASM_FILE_START for each target. */ |
| |
| void |
| darwin_file_start (void) |
| { |
| /* Nothing to do. */ |
| } |
| |
| /* Called for the TARGET_ASM_FILE_END hook. |
| Emit the mach-o pic indirection data, the lto data and, finally a flag |
| to tell the linker that it can break the file object into sections and |
| move those around for efficiency. */ |
| |
| void |
| darwin_file_end (void) |
| { |
| if (!vec_safe_is_empty (ctors)) |
| finalize_ctors (); |
| if (!vec_safe_is_empty (dtors)) |
| finalize_dtors (); |
| |
| /* If we are expecting to output NeXT ObjC meta-data, (and we actually see |
| some) then we output the fix-and-continue marker (Image Info). |
| This applies to Objective C, Objective C++ and LTO with either language |
| as part of the input. */ |
| if (flag_next_runtime && objc_metadata_seen) |
| { |
| unsigned int flags = 0; |
| if (flag_objc_abi >= 2) |
| { |
| flags = 16; |
| switch_to_section (darwin_sections[objc2_image_info_section]); |
| } |
| else |
| switch_to_section (darwin_sections[objc_image_info_section]); |
| |
| ASM_OUTPUT_ALIGN (asm_out_file, 2); |
| fputs ("L_OBJC_ImageInfo:\n", asm_out_file); |
| |
| flags |= (flag_replace_objc_classes && classes_seen) ? 1 : 0; |
| flags |= flag_objc_gc ? 2 : 0; |
| |
| fprintf (asm_out_file, "\t.long\t0\n\t.long\t%u\n", flags); |
| } |
| |
| machopic_finish (asm_out_file); |
| if (flag_apple_kext) |
| { |
| /* These sections are only used for kernel code. */ |
| switch_to_section (darwin_sections[constructor_section]); |
| switch_to_section (darwin_sections[destructor_section]); |
| ASM_OUTPUT_ALIGN (asm_out_file, 1); |
| } |
| |
| /* If there was LTO assembler output, append it to asm_out_file. */ |
| if (lto_asm_out_name) |
| { |
| int n; |
| char *buf, *lto_asm_txt; |
| |
| /* Shouldn't be here if we failed to switch back. */ |
| gcc_assert (! saved_asm_out_file); |
| |
| lto_asm_out_file = fopen (lto_asm_out_name, "r"); |
| if (lto_asm_out_file == NULL) |
| fatal_error (input_location, |
| "failed to open temporary file %s with LTO output", |
| lto_asm_out_name); |
| fseek (lto_asm_out_file, 0, SEEK_END); |
| n = ftell (lto_asm_out_file); |
| if (n > 0) |
| { |
| fseek (lto_asm_out_file, 0, SEEK_SET); |
| lto_asm_txt = buf = (char *) xmalloc (n + 1); |
| while (fgets (lto_asm_txt, n, lto_asm_out_file)) |
| fputs (lto_asm_txt, asm_out_file); |
| /* Put a termination label. */ |
| fprintf (asm_out_file, "\t.section %s,%s,regular,debug\n", |
| LTO_SEGMENT_NAME, LTO_SECTS_SECTION); |
| fprintf (asm_out_file, "L_GNU_LTO%d:\t;# end of lto\n", |
| lto_section_num); |
| /* Make sure our termination label stays in this section. */ |
| fputs ("\t.space\t1\n", asm_out_file); |
| } |
| |
| /* Remove the temporary file. */ |
| fclose (lto_asm_out_file); |
| unlink_if_ordinary (lto_asm_out_name); |
| free (lto_asm_out_name); |
| } |
| |
| /* Output the names and indices. */ |
| if (lto_section_names && lto_section_names->length ()) |
| { |
| int count; |
| darwin_lto_section_e *ref; |
| /* For now, we'll make the offsets 4 bytes and unaligned - we'll fix |
| the latter up ourselves. */ |
| const char *op = integer_asm_op (4,0); |
| |
| /* Emit the names. */ |
| fprintf (asm_out_file, "\t.section %s,%s,regular,debug\n", |
| LTO_SEGMENT_NAME, LTO_NAMES_SECTION); |
| FOR_EACH_VEC_ELT (*lto_section_names, count, ref) |
| { |
| fprintf (asm_out_file, "L_GNU_LTO_NAME%d:\n", count); |
| /* We have to jump through hoops to get the values of the intra-section |
| offsets... */ |
| fprintf (asm_out_file, |
| "\t.set L$gnu$lto$noff%d,L_GNU_LTO_NAME%d-L_GNU_LTO_NAME0\n", |
| count, count); |
| fprintf (asm_out_file, |
| "\t.set L$gnu$lto$nsiz%d,L_GNU_LTO_NAME%d-L_GNU_LTO_NAME%d\n", |
| count, count+1, count); |
| fprintf (asm_out_file, "\t.asciz\t\"%s\"\n", ref->sectname); |
| } |
| fprintf (asm_out_file, "L_GNU_LTO_NAME%d:\t;# end\n", lto_section_num); |
| /* make sure our termination label stays in this section. */ |
| fputs ("\t.space\t1\n", asm_out_file); |
| |
| /* Emit the Index. */ |
| fprintf (asm_out_file, "\t.section %s,%s,regular,debug\n", |
| LTO_SEGMENT_NAME, LTO_INDEX_SECTION); |
| fputs ("\t.align\t2\n", asm_out_file); |
| fputs ("# Section offset, Section length, Name offset, Name length\n", |
| asm_out_file); |
| FOR_EACH_VEC_ELT (*lto_section_names, count, ref) |
| { |
| fprintf (asm_out_file, "%s L$gnu$lto$offs%d\t;# %s\n", |
| op, count, ref->sectname); |
| fprintf (asm_out_file, "%s L$gnu$lto$size%d\n", op, count); |
| fprintf (asm_out_file, "%s L$gnu$lto$noff%d\n", op, count); |
| fprintf (asm_out_file, "%s L$gnu$lto$nsiz%d\n", op, count); |
| } |
| } |
| |
| /* If we have section anchors, then we must prevent the linker from |
| re-arranging data. */ |
| if (!DARWIN_SECTION_ANCHORS || !flag_section_anchors) |
| fprintf (asm_out_file, "\t.subsections_via_symbols\n"); |
| |
| /* We rely on this being NULL at the start of compilation; reset it here |
| so that JIT can reuse a context. */ |
| if (dwarf_sect_names_table != NULL) |
| { |
| dwarf_sect_names_table->truncate (0); |
| dwarf_sect_names_table = NULL; |
| } |
| } |
| |
| /* TODO: Add a language hook for identifying if a decl is a vtable. */ |
| #define DARWIN_VTABLE_P(DECL) 0 |
| |
| /* Cross-module name binding. Darwin does not support overriding |
| functions at dynamic-link time, except for vtables in kexts. */ |
| |
|