gcc/output.h

/* Declarations for insn-output.c and other code to write to asm_out_file.
   These functions are defined in final.c, and varasm.c.
   Copyright (C) 1987-2015 Free Software Foundation, Inc.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.

GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  */

#ifndef GCC_OUTPUT_H
#define GCC_OUTPUT_H

/* Initialize data in final at the beginning of a compilation.  */
extern void init_final (const char *);

/* Enable APP processing of subsequent output.
   Used before the output from an `asm' statement.  */
extern void app_enable (void);

/* Disable APP processing of subsequent output.
   Called from varasm.c before most kinds of output.  */
extern void app_disable (void);

/* Return the number of slots filled in the current
   delayed branch sequence (we don't count the insn needing the
   delay slot).   Zero if not in a delayed branch sequence.  */
extern int dbr_sequence_length (void);

/* Indicate that branch shortening hasn't yet been done.  */
extern void init_insn_lengths (void);

/* Obtain the current length of an insn.  If branch shortening has been done,
   get its actual length.  Otherwise, get its maximum length.  */
extern int get_attr_length (rtx_insn *);

/* Obtain the current length of an insn.  If branch shortening has been done,
   get its actual length.  Otherwise, get its minimum length.  */
extern int get_attr_min_length (rtx_insn *);

/* Make a pass over all insns and compute their actual lengths by shortening
   any branches of variable length if possible.  */
extern void shorten_branches (rtx_insn *);

const char *get_some_local_dynamic_name ();

/* Output assembler code for the start of a function,
   and initialize some of the variables in this file
   for the new function.  The label for the function and associated
   assembler pseudo-ops have already been output in
   `assemble_start_function'.  */
extern void final_start_function (rtx_insn *, FILE *, int);

/* Output assembler code for the end of a function.
   For clarity, args are same as those of `final_start_function'
   even though not all of them are needed.  */
extern void final_end_function (void);

/* Output assembler code for some insns: all or part of a function.  */
extern void final (rtx_insn *, FILE *, int);

/* The final scan for one insn, INSN.  Args are same as in `final', except
   that INSN is the insn being scanned.  Value returned is the next insn to
   be scanned.  */
extern rtx_insn *final_scan_insn (rtx_insn *, FILE *, int, int, int *);

/* Replace a SUBREG with a REG or a MEM, based on the thing it is a
   subreg of.  */
extern rtx alter_subreg (rtx *, bool);

/* Print an operand using machine-dependent assembler syntax.  */
extern void output_operand (rtx, int);

/* Report inconsistency between the assembler template and the operands.
   In an `asm', it's the user's fault; otherwise, the compiler's fault.  */
extern void output_operand_lossage (const char *, ...) ATTRIBUTE_PRINTF_1;

/* Output a string of assembler code, substituting insn operands.
   Defined in final.c.  */
extern void output_asm_insn (const char *, rtx *);

/* Compute a worst-case reference address of a branch so that it
   can be safely used in the presence of aligned labels.
   Defined in final.c.  */
extern int insn_current_reference_address (rtx_insn *);

/* Find the alignment associated with a CODE_LABEL.
   Defined in final.c.  */
extern int label_to_alignment (rtx);

/* Find the alignment maximum skip associated with a CODE_LABEL.
   Defined in final.c.  */
extern int label_to_max_skip (rtx);

/* Output a LABEL_REF, or a bare CODE_LABEL, as an assembler symbol.  */
extern void output_asm_label (rtx);

/* Marks SYMBOL_REFs in x as referenced through use of assemble_external.  */
extern void mark_symbol_refs_as_used (rtx);

/* Print a memory reference operand for address X
   using machine-dependent assembler syntax.  */
extern void output_address (rtx);

/* Print an integer constant expression in assembler syntax.
   Addition and subtraction are the only arithmetic
   that may appear in these expressions.  */
extern void output_addr_const (FILE *, rtx);

/* Output a string of assembler code, substituting numbers, strings
   and fixed syntactic prefixes.  */
#if GCC_VERSION >= 3004
#define ATTRIBUTE_ASM_FPRINTF(m, n) __attribute__ ((__format__ (__asm_fprintf__, m, n))) ATTRIBUTE_NONNULL(m)
#else
#define ATTRIBUTE_ASM_FPRINTF(m, n) ATTRIBUTE_NONNULL(m)
#endif

extern void fprint_whex (FILE *, unsigned HOST_WIDE_INT);
extern void fprint_ul (FILE *, unsigned long);
extern int sprint_ul (char *, unsigned long);

extern void asm_fprintf (FILE *file, const char *p, ...)
     ATTRIBUTE_ASM_FPRINTF(2, 3);

/* Return nonzero if this function has no function calls.  */
extern int leaf_function_p (void);

/* Return 1 if branch is a forward branch.
   Uses insn_shuid array, so it works only in the final pass.  May be used by
   output templates to add branch prediction hints, for example.  */
extern int final_forward_branch_p (rtx_insn *);

/* Return 1 if this function uses only the registers that can be
   safely renumbered.  */
extern int only_leaf_regs_used (void);

/* Scan IN_RTX and its subexpressions, and renumber all regs into those
   available in leaf functions.  */
extern void leaf_renumber_regs_insn (rtx);

/* Locate the proper template for the given insn-code.  */
extern const char *get_insn_template (int, rtx);

/* Functions in varasm.c.  */

/* Emit any pending weak declarations.  */
extern void weak_finish (void);

/* Decode an `asm' spec for a declaration as a register name.
   Return the register number, or -1 if nothing specified,
   or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
   or -3 if ASMSPEC is `cc' and is not recognized,
   or -4 if ASMSPEC is `memory' and is not recognized.
   Accept an exact spelling or a decimal number.
   Prefixes such as % are optional.  */
extern int decode_reg_name (const char *);

/* Similar to decode_reg_name, but takes an extra parameter that is a
   pointer to the number of (internal) registers described by the
   external name.  */
extern int decode_reg_name_and_count (const char *, int *);

extern void do_assemble_alias (tree, tree);

extern void default_assemble_visibility (tree, int);

/* Output a string of literal assembler code
   for an `asm' keyword used between functions.  */
extern void assemble_asm (tree);

/* Get the function's name from a decl, as described by its RTL.  */
extern const char *get_fnname_from_decl (tree);

/* Output assembler code for the constant pool of a function and associated
   with defining the name of the function.  DECL describes the function.
   NAME is the function's name.  For the constant pool, we use the current
   constant pool data.  */
extern void assemble_start_function (tree, const char *);

/* Output assembler code associated with defining the size of the
   function.  DECL describes the function.  NAME is the function's name.  */
extern void assemble_end_function (tree, const char *);

/* Assemble everything that is needed for a variable or function declaration.
   Not used for automatic variables, and not used for function definitions.
   Should not be called for variables of incomplete structure type.

   TOP_LEVEL is nonzero if this variable has file scope.
   AT_END is nonzero if this is the special handling, at end of compilation,
   to define things that have had only tentative definitions.
   DONT_OUTPUT_DATA if nonzero means don't actually output the
   initial value (that will be done by the caller).  */
extern void assemble_variable (tree, int, int, int);

/* Put the vtable verification constructor initialization function
   into the preinit array.  */
extern void assemble_vtv_preinit_initializer (tree);

/* Assemble everything that is needed for a variable declaration that has
   no definition in the current translation unit.  */
extern void assemble_undefined_decl (tree);

/* Compute the alignment of variable specified by DECL.
   DONT_OUTPUT_DATA is from assemble_variable.  */
extern void align_variable (tree decl, bool dont_output_data);

/* Queue for outputting something to declare an external symbol to the
   assembler.  (Most assemblers don't need this, so we normally output
   nothing.)  Do nothing if DECL is not external.  */
extern void assemble_external (tree);

/* Assemble code to leave SIZE bytes of zeros.  */
extern void assemble_zeros (unsigned HOST_WIDE_INT);

/* Assemble an alignment pseudo op for an ALIGN-bit boundary.  */
extern void assemble_align (int);

/* Assemble a string constant with the specified C string as contents.  */
extern void assemble_string (const char *, int);

/* Similar, for calling a library function FUN.  */
extern void assemble_external_libcall (rtx);

/* Assemble a label named NAME.  */
extern void assemble_label (FILE *, const char *);

/* Output to FILE (an assembly file) a reference to NAME.  If NAME
   starts with a *, the rest of NAME is output verbatim.  Otherwise
   NAME is transformed in a target-specific way (usually by the
   addition of an underscore).  */
extern void assemble_name_raw (FILE *, const char *);

/* Like assemble_name_raw, but should be used when NAME might refer to
   an entity that is also represented as a tree (like a function or
   variable).  If NAME does refer to such an entity, that entity will
   be marked as referenced.  */
extern void assemble_name (FILE *, const char *);

/* Return the assembler directive for creating a given kind of integer
   object.  SIZE is the number of bytes in the object and ALIGNED_P
   indicates whether it is known to be aligned.  Return NULL if the
   assembly dialect has no such directive.

   The returned string should be printed at the start of a new line and
   be followed immediately by the object's initial value.  */
extern const char *integer_asm_op (int, int);

/* Use directive OP to assemble an integer object X.  Print OP at the
   start of the line, followed immediately by the value of X.  */
extern void assemble_integer_with_op (const char *, rtx);

/* The default implementation of the asm_out.integer target hook.  */
extern bool default_assemble_integer (rtx, unsigned int, int);

/* Assemble the integer constant X into an object of SIZE bytes.  ALIGN is
   the alignment of the integer in bits.  Return 1 if we were able to output
   the constant, otherwise 0.  If FORCE is nonzero the constant must
   be outputable. */
extern bool assemble_integer (rtx, unsigned, unsigned, int);

/* Return section for TEXT_SECITON_NAME if DECL or DECL_SECTION_NAME (DECL)
   is NULL.  */
extern section *get_named_text_section (tree, const char *, const char *);

/* An interface to assemble_integer for the common case in which a value is
   fully aligned and must be printed.  VALUE is the value of the integer
   object and SIZE is the number of bytes it contains.  */
#define assemble_aligned_integer(SIZE, VALUE) \
  assemble_integer (VALUE, SIZE, (SIZE) * BITS_PER_UNIT, 1)

#ifdef REAL_VALUE_TYPE_SIZE
/* Assemble the floating-point constant D into an object of size MODE.  */
extern void assemble_real (REAL_VALUE_TYPE, machine_mode, unsigned);
#endif

/* Write the address of the entity given by SYMBOL to SEC.  */
extern void assemble_addr_to_section (rtx, section *);

/* Return the size of the constant pool.  */
extern int get_pool_size (void);

#ifdef HAVE_peephole
extern rtx_insn *peephole (rtx_insn *);
#endif

extern void output_shared_constant_pool (void);

extern void output_object_blocks (void);

extern void output_quoted_string (FILE *, const char *);

/* When outputting delayed branch sequences, this rtx holds the
   sequence being output.  It is null when no delayed branch
   sequence is being output, so it can be used as a test in the
   insn output code.

   This variable is defined  in final.c.  */
extern rtx_sequence *final_sequence;

/* The line number of the beginning of the current function.  Various
   md code needs this so that it can output relative linenumbers.  */

#ifdef SDB_DEBUGGING_INFO /* Avoid undef sym in certain broken linkers.  */
extern int sdb_begin_function_line;
#endif

/* File in which assembler code is being written.  */

#ifdef BUFSIZ
extern FILE *asm_out_file;
#endif

/* The first global object in the file.  */
extern const char *first_global_object_name;

/* The first weak object in the file.  */
extern const char *weak_global_object_name;

/* Nonnull if the insn currently being emitted was a COND_EXEC pattern.  */
extern rtx current_insn_predicate;

/* Last insn processed by final_scan_insn.  */
extern rtx_insn *current_output_insn;

/* Nonzero while outputting an `asm' with operands.
   This means that inconsistencies are the user's fault, so don't die.
   The precise value is the insn being output, to pass to error_for_asm.  */
extern const rtx_insn *this_is_asm_operands;

/* Carry information from ASM_DECLARE_OBJECT_NAME
   to ASM_FINISH_DECLARE_OBJECT.  */
extern int size_directive_output;
extern tree last_assemble_variable_decl;

extern bool first_function_block_is_cold;

/* Decide whether DECL needs to be in a writable section.
   RELOC is the same as for SELECT_SECTION.  */
extern bool decl_readonly_section (const_tree, int);

/* This can be used to compute RELOC for the function above, when
   given a constant expression.  */
extern int compute_reloc_for_constant (tree);

/* User label prefix in effect for this compilation.  */
extern const char *user_label_prefix;

/* Default target function prologue and epilogue assembler output.  */
extern void default_function_pro_epilogue (FILE *, HOST_WIDE_INT);

/* Default target function switched text sections.  */
extern void default_function_switched_text_sections (FILE *, tree, bool);

/* Default target hook that outputs nothing to a stream.  */
extern void no_asm_to_stream (FILE *);

/* Flags controlling properties of a section.  */
#define SECTION_ENTSIZE	 0x000ff	/* entity size in section */
#define SECTION_CODE	 0x00100	/* contains code */
#define SECTION_WRITE	 0x00200	/* data is writable */
#define SECTION_DEBUG	 0x00400	/* contains debug data */
#define SECTION_LINKONCE 0x00800	/* is linkonce */
#define SECTION_SMALL	 0x01000	/* contains "small data" */
#define SECTION_BSS	 0x02000	/* contains zeros only */
#define SECTION_FORGET	 0x04000	/* forget that we've entered the section */
#define SECTION_MERGE	 0x08000	/* contains mergeable data */
#define SECTION_STRINGS  0x10000	/* contains zero terminated strings without
					   embedded zeros */
#define SECTION_OVERRIDE 0x20000	/* allow override of default flags */
#define SECTION_TLS	 0x40000	/* contains thread-local storage */
#define SECTION_NOTYPE	 0x80000	/* don't output @progbits */
#define SECTION_DECLARED 0x100000	/* section has been used */
#define SECTION_STYLE_MASK 0x600000	/* bits used for SECTION_STYLE */
#define SECTION_COMMON   0x800000	/* contains common data */
#define SECTION_RELRO	 0x1000000	/* data is readonly after relocation processing */
#define SECTION_EXCLUDE  0x2000000	/* discarded by the linker */
#define SECTION_MACH_DEP 0x4000000	/* subsequent bits reserved for target */

/* This SECTION_STYLE is used for unnamed sections that we can switch
   to using a special assembler directive.  */
#define SECTION_UNNAMED	 0x000000

/* This SECTION_STYLE is used for named sections that we can switch
   to using a general section directive.  */
#define SECTION_NAMED	 0x200000

/* This SECTION_STYLE is used for sections that we cannot switch to at
   all.  The choice of section is implied by the directive that we use
   to declare the object.  */
#define SECTION_NOSWITCH 0x400000

/* A helper function for default_elf_select_section and
   default_elf_unique_section.  Categorizes the DECL.  */

enum section_category
{
  SECCAT_TEXT,

  SECCAT_RODATA,
  SECCAT_RODATA_MERGE_STR,
  SECCAT_RODATA_MERGE_STR_INIT,
  SECCAT_RODATA_MERGE_CONST,
  SECCAT_SRODATA,

  SECCAT_DATA,

  /* To optimize loading of shared programs, define following subsections
     of data section:
	_REL	Contains data that has relocations, so they get grouped
		together and dynamic linker will visit fewer pages in memory.
	_RO	Contains data that is otherwise read-only.  This is useful
		with prelinking as most relocations won't be dynamically
		linked and thus stay read only.
	_LOCAL	Marks data containing relocations only to local objects.
		These relocations will get fully resolved by prelinking.  */
  SECCAT_DATA_REL,
  SECCAT_DATA_REL_LOCAL,
  SECCAT_DATA_REL_RO,
  SECCAT_DATA_REL_RO_LOCAL,

  SECCAT_SDATA,
  SECCAT_TDATA,

  SECCAT_BSS,
  SECCAT_SBSS,
  SECCAT_TBSS
};

/* Information that is provided by all instances of the section type.  */
struct GTY(()) section_common {
  /* The set of SECTION_* flags that apply to this section.  */
  unsigned int flags;
};

/* Information about a SECTION_NAMED section.  */
struct GTY(()) named_section {
  struct section_common common;

  /* The name of the section.  */
  const char *name;

  /* If nonnull, the VAR_DECL or FUNCTION_DECL with which the
     section is associated.  */
  tree decl;
};

/* A callback that writes the assembly code for switching to an unnamed
   section.  The argument provides callback-specific data.  */
typedef void (*unnamed_section_callback) (const void *);

/* Information about a SECTION_UNNAMED section.  */
struct GTY(()) unnamed_section {
  struct section_common common;

  /* The callback used to switch to the section, and the data that
     should be passed to the callback.  */
  unnamed_section_callback GTY ((skip)) callback;
  const void *GTY ((skip)) data;

  /* The next entry in the chain of unnamed sections.  */
  section *next;
};

/* A callback that writes the assembly code for a decl in a
   SECTION_NOSWITCH section.  DECL is the decl that should be assembled
   and NAME is the name of its SYMBOL_REF.  SIZE is the size of the decl
   in bytes and ROUNDED is that size rounded up to the next
   BIGGEST_ALIGNMENT / BITS_PER_UNIT boundary.

   Return true if the callback used DECL_ALIGN to set the object's
   alignment.  A false return value implies that we are relying
   on the rounded size to align the decl.  */
typedef bool (*noswitch_section_callback) (tree decl, const char *name,
					   unsigned HOST_WIDE_INT size,
					   unsigned HOST_WIDE_INT rounded);

/* Information about a SECTION_NOSWITCH section.  */
struct GTY(()) noswitch_section {
  struct section_common common;

  /* The callback used to assemble decls in this section.  */
  noswitch_section_callback GTY ((skip)) callback;
};

/* Information about a section, which may be named or unnamed.  */
union GTY ((desc ("SECTION_STYLE (&(%h))"), for_user)) section {
  struct section_common GTY ((skip)) common;
  struct named_section GTY ((tag ("SECTION_NAMED"))) named;
  struct unnamed_section GTY ((tag ("SECTION_UNNAMED"))) unnamed;
  struct noswitch_section GTY ((tag ("SECTION_NOSWITCH"))) noswitch;
};

/* Return the style of section SECT.  */
#define SECTION_STYLE(SECT) ((SECT)->common.flags & SECTION_STYLE_MASK)

struct object_block;

/* Special well-known sections.  */
extern GTY(()) section *text_section;
extern GTY(()) section *data_section;
extern GTY(()) section *readonly_data_section;
extern GTY(()) section *sdata_section;
extern GTY(()) section *ctors_section;
extern GTY(()) section *dtors_section;
extern GTY(()) section *bss_section;
extern GTY(()) section *sbss_section;
extern GTY(()) section *exception_section;
extern GTY(()) section *eh_frame_section;
extern GTY(()) section *tls_comm_section;
extern GTY(()) section *comm_section;
extern GTY(()) section *lcomm_section;
extern GTY(()) section *bss_noswitch_section;

extern GTY(()) section *in_section;
extern GTY(()) bool in_cold_section_p;

extern section *get_unnamed_section (unsigned int, void (*) (const void *),
				     const void *);
extern section *get_section (const char *, unsigned int, tree);
extern section *get_named_section (tree, const char *, int);
extern section *get_variable_section (tree, bool);
extern void place_block_symbol (rtx);
extern rtx get_section_anchor (struct object_block *, HOST_WIDE_INT,
			       enum tls_model);
extern section *mergeable_constant_section (machine_mode,
					    unsigned HOST_WIDE_INT,
					    unsigned int);
extern section *function_section (tree);
extern section *unlikely_text_section (void);
extern section *current_function_section (void);

/* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
   not) section for PRIORITY.  */
extern section *get_cdtor_priority_section (int, bool);

extern bool unlikely_text_section_p (section *);
extern void switch_to_section (section *);
extern void output_section_asm_op (const void *);

extern void record_tm_clone_pair (tree, tree);
extern void finish_tm_clone_pairs (void);
extern tree get_tm_clone_pair (tree);

extern void default_asm_output_source_filename (FILE *, const char *);
extern void output_file_directive (FILE *, const char *);

extern unsigned int default_section_type_flags (tree, const char *, int);

extern bool have_global_bss_p (void);
extern bool bss_initializer_p (const_tree);

extern void default_no_named_section (const char *, unsigned int, tree);
extern void default_elf_asm_named_section (const char *, unsigned int, tree);
extern enum section_category categorize_decl_for_section (const_tree, int);
extern void default_coff_asm_named_section (const char *, unsigned int, tree);
extern void default_pe_asm_named_section (const char *, unsigned int, tree);

extern void default_named_section_asm_out_destructor (rtx, int);
extern void default_dtor_section_asm_out_destructor (rtx, int);
extern void default_named_section_asm_out_constructor (rtx, int);
extern void default_ctor_section_asm_out_constructor (rtx, int);

extern section *default_select_section (tree, int, unsigned HOST_WIDE_INT);
extern section *default_elf_select_section (tree, int, unsigned HOST_WIDE_INT);
extern void default_unique_section (tree, int);
extern section *default_function_rodata_section (tree);
extern section *default_no_function_rodata_section (tree);
extern section *default_clone_table_section (void);
extern section *default_select_rtx_section (machine_mode, rtx,
					    unsigned HOST_WIDE_INT);
extern section *default_elf_select_rtx_section (machine_mode, rtx,
						unsigned HOST_WIDE_INT);
extern void default_encode_section_info (tree, rtx, int);
extern const char *default_strip_name_encoding (const char *);
extern void default_asm_output_anchor (rtx);
extern bool default_use_anchors_for_symbol_p (const_rtx);
extern bool default_binds_local_p (const_tree);
extern bool default_binds_local_p_1 (const_tree, int);
extern bool default_binds_local_p_2 (const_tree);
extern bool default_binds_local_p_3 (const_tree, bool, bool, bool, bool);
extern void default_globalize_label (FILE *, const char *);
extern void default_globalize_decl_name (FILE *, tree);
extern void default_emit_unwind_label (FILE *, tree, int, int);
extern void default_emit_except_table_label (FILE *);
extern void default_generate_internal_label (char *, const char *,
					     unsigned long);
extern void default_internal_label (FILE *, const char *, unsigned long);
extern void default_asm_declare_constant_name (FILE *, const char *,
					       const_tree, HOST_WIDE_INT);
extern void default_file_start (void);
extern void file_end_indicate_exec_stack (void);
extern void file_end_indicate_split_stack (void);

extern void default_elf_asm_output_external (FILE *file, tree,
					     const char *);
extern void default_elf_asm_output_limited_string (FILE *, const char *);
extern void default_elf_asm_output_ascii (FILE *, const char *, unsigned int);
extern void default_elf_internal_label (FILE *, const char *, unsigned long);

extern void default_elf_init_array_asm_out_constructor (rtx, int);
extern void default_elf_fini_array_asm_out_destructor (rtx, int);
extern int maybe_assemble_visibility (tree);

extern int default_address_cost (rtx, machine_mode, addr_space_t, bool);

/* Output stack usage information.  */
extern void output_stack_usage (void);

#endif /* ! GCC_OUTPUT_H */