[deliverable/binutils-gdb.git] / gdb / dwarf2expr.h

/* DWARF 2 Expression Evaluator.

   Copyright (C) 2001-2016 Free Software Foundation, Inc.

   Contributed by Daniel Berlin <dan@dberlin.org>.

   This file is part of GDB.

   This program 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 of the License, or
   (at your option) any later version.

   This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.  */

#if !defined (DWARF2EXPR_H)
#define DWARF2EXPR_H

#include "leb128.h"
#include "gdbtypes.h"

/* The location of a value.  */
enum dwarf_value_location
{
  /* The piece is in memory.
     The value on the dwarf stack is its address.  */
  DWARF_VALUE_MEMORY,

  /* The piece is in a register.
     The value on the dwarf stack is the register number.  */
  DWARF_VALUE_REGISTER,

  /* The piece is on the dwarf stack.  */
  DWARF_VALUE_STACK,

  /* The piece is a literal.  */
  DWARF_VALUE_LITERAL,

  /* The piece was optimized out.  */
  DWARF_VALUE_OPTIMIZED_OUT,

  /* The piece is an implicit pointer.  */
  DWARF_VALUE_IMPLICIT_POINTER
};

/* The dwarf expression stack.  */

struct dwarf_stack_value
{
  struct value *value;

  /* Non-zero if the piece is in memory and is known to be
     on the program's stack.  It is always ok to set this to zero.
     This is used, for example, to optimize memory access from the target.
     It can vastly speed up backtraces on long latency connections when
     "set stack-cache on".  */
  int in_stack_memory;
};

/* The expression evaluator works with a dwarf_expr_context, describing
   its current state and its callbacks.  */
struct dwarf_expr_context
{
  dwarf_expr_context ();
  ~dwarf_expr_context ();

  void push_address (CORE_ADDR value, int in_stack_memory);
  void eval (const gdb_byte *addr, size_t len);
  struct value *fetch (int n);
  CORE_ADDR fetch_address (int n);
  int fetch_in_stack_memory (int n);

  /* The stack of values, allocated with xmalloc.  */
  struct dwarf_stack_value *stack;

  /* The number of values currently pushed on the stack, and the
     number of elements allocated to the stack.  */
  int stack_len, stack_allocated;

  /* Target architecture to use for address operations.  */
  struct gdbarch *gdbarch;

  /* Target address size in bytes.  */
  int addr_size;

  /* DW_FORM_ref_addr size in bytes.  If -1 DWARF is executed from a frame
     context and operations depending on DW_FORM_ref_addr are not allowed.  */
  int ref_addr_size;

  /* Offset used to relocate DW_OP_addr and DW_OP_GNU_addr_index arguments.  */
  CORE_ADDR offset;

  /* The current depth of dwarf expression recursion, via DW_OP_call*,
     DW_OP_fbreg, DW_OP_push_object_address, etc., and the maximum
     depth we'll tolerate before raising an error.  */
  int recursion_depth, max_recursion_depth;

  /* Location of the value.  */
  enum dwarf_value_location location;

  /* For DWARF_VALUE_LITERAL, the current literal value's length and
     data.  For DWARF_VALUE_IMPLICIT_POINTER, LEN is the offset of the
     target DIE of sect_offset kind.  */
  ULONGEST len;
  const gdb_byte *data;

  /* Initialization status of variable: Non-zero if variable has been
     initialized; zero otherwise.  */
  int initialized;

  /* An array of pieces.  PIECES points to its first element;
     NUM_PIECES is its length.

     Each time DW_OP_piece is executed, we add a new element to the
     end of this array, recording the current top of the stack, the
     current location, and the size given as the operand to
     DW_OP_piece.  We then pop the top value from the stack, reset the
     location, and resume evaluation.

     The Dwarf spec doesn't say whether DW_OP_piece pops the top value
     from the stack.  We do, ensuring that clients of this interface
     expecting to see a value left on the top of the stack (say, code
     evaluating frame base expressions or CFA's specified with
     DW_CFA_def_cfa_expression) will get an error if the expression
     actually marks all the values it computes as pieces.

     If an expression never uses DW_OP_piece, num_pieces will be zero.
     (It would be nice to present these cases as expressions yielding
     a single piece, so that callers need not distinguish between the
     no-DW_OP_piece and one-DW_OP_piece cases.  But expressions with
     no DW_OP_piece operations have no value to place in a piece's
     'size' field; the size comes from the surrounding data.  So the
     two cases need to be handled separately.)  */
  int num_pieces;
  struct dwarf_expr_piece *pieces;

  /* Return the value of register number REGNUM (a DWARF register number),
     read as an address.  */
  virtual CORE_ADDR read_addr_from_reg (int regnum) = 0;

  /* Return a value of type TYPE, stored in register number REGNUM
     of the frame associated to the given BATON.

     REGNUM is a DWARF register number.  */
  virtual struct value *get_reg_value (struct type *type, int regnum) = 0;

  /* Read LENGTH bytes at ADDR into BUF.  */
  virtual void read_mem (gdb_byte *buf, CORE_ADDR addr, size_t length) = 0;

  /* Return the location expression for the frame base attribute, in
     START and LENGTH.  The result must be live until the current
     expression evaluation is complete.  */
  virtual void get_frame_base (const gdb_byte **start, size_t *length)
  {
    error (_("%s is invalid in this context"), "DW_OP_fbreg");
  }

  /* Return the CFA for the frame.  */
  virtual CORE_ADDR get_frame_cfa ()
  {
    error (_("%s is invalid in this context"), "DW_OP_call_frame_cfa");
  }

  /* Return the PC for the frame.  */
  virtual CORE_ADDR get_frame_pc ()
  {
    error (_("%s is invalid in this context"), "DW_OP_GNU_implicit_pointer");
  }

  /* Return the thread-local storage address for
     DW_OP_GNU_push_tls_address or DW_OP_form_tls_address.  */
  virtual CORE_ADDR get_tls_address (CORE_ADDR offset)
  {
    error (_("%s is invalid in this context"), "DW_OP_form_tls_address");
  }

  /* Execute DW_AT_location expression for the DWARF expression
     subroutine in the DIE at DIE_OFFSET in the CU.  Do not touch
     STACK while it being passed to and returned from the called DWARF
     subroutine.  */
  virtual void dwarf_call (cu_offset die_offset)
  {
    error (_("%s is invalid in this context"), "DW_OP_call*");
  }

  /* Return the base type given by the indicated DIE.  This can throw
     an exception if the DIE is invalid or does not represent a base
     type.  If can also be NULL in the special case where the
     callbacks are not performing evaluation, and thus it is
     meaningful to substitute a stub type of the correct size.  */
  virtual struct type *impl_get_base_type (cu_offset die)
  {
    /* Anything will do.  */
    return builtin_type (this->gdbarch)->builtin_int;
  }

  /* Push on DWARF stack an entry evaluated for DW_TAG_GNU_call_site's
     parameter matching KIND and KIND_U at the caller of specified BATON.
     If DEREF_SIZE is not -1 then use DW_AT_GNU_call_site_data_value instead of
     DW_AT_GNU_call_site_value.  */
  virtual void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind,
					   union call_site_parameter_u kind_u,
					   int deref_size)
  {
    internal_error (__FILE__, __LINE__,
		    _("Support for DW_OP_GNU_entry_value is unimplemented"));
  }

  /* Return the address indexed by DW_OP_GNU_addr_index.
     This can throw an exception if the index is out of range.  */
  virtual CORE_ADDR get_addr_index (unsigned int index)
  {
    error (_("%s is invalid in this context"), "DW_OP_GNU_addr_index");
  }

  /* Return the `object address' for DW_OP_push_object_address.  */
  virtual CORE_ADDR get_object_address ()
  {
    internal_error (__FILE__, __LINE__,
		    _("Support for DW_OP_push_object_address "
		      "is unimplemented"));
  }

private:

  struct type *address_type () const;
  void grow_stack (size_t need);
  void push (struct value *value, int in_stack_memory);
  int stack_empty_p () const;
  void add_piece (ULONGEST size, ULONGEST offset);
  struct type *get_base_type (cu_offset die, int size);
  void execute_stack_op (const gdb_byte *op_ptr, const gdb_byte *op_end);
  void pop ();
};


/* A piece of an object, as recorded by DW_OP_piece or DW_OP_bit_piece.  */
struct dwarf_expr_piece
{
  enum dwarf_value_location location;

  union
  {
    struct
    {
      /* This piece's address, for DWARF_VALUE_MEMORY pieces.  */
      CORE_ADDR addr;
      /* Non-zero if the piece is known to be in memory and on
	 the program's stack.  */
      int in_stack_memory;
    } mem;

    /* The piece's register number, for DWARF_VALUE_REGISTER pieces.  */
    int regno;

    /* The piece's literal value, for DWARF_VALUE_STACK pieces.  */
    struct value *value;

    struct
    {
      /* A pointer to the data making up this piece,
	 for DWARF_VALUE_LITERAL pieces.  */
      const gdb_byte *data;
      /* The length of the available data.  */
      ULONGEST length;
    } literal;

    /* Used for DWARF_VALUE_IMPLICIT_POINTER.  */
    struct
    {
      /* The referent DIE from DW_OP_GNU_implicit_pointer.  */
      sect_offset die;
      /* The byte offset into the resulting data.  */
      LONGEST offset;
    } ptr;
  } v;

  /* The length of the piece, in bits.  */
  ULONGEST size;
  /* The piece offset, in bits.  */
  ULONGEST offset;
};

void dwarf_expr_require_composition (const gdb_byte *, const gdb_byte *,
				     const char *);

int dwarf_block_to_dwarf_reg (const gdb_byte *buf, const gdb_byte *buf_end);

int dwarf_block_to_dwarf_reg_deref (const gdb_byte *buf,
				    const gdb_byte *buf_end,
				    CORE_ADDR *deref_size_return);

int dwarf_block_to_fb_offset (const gdb_byte *buf, const gdb_byte *buf_end,
			      CORE_ADDR *fb_offset_return);

int dwarf_block_to_sp_offset (struct gdbarch *gdbarch, const gdb_byte *buf,
			      const gdb_byte *buf_end,
			      CORE_ADDR *sp_offset_return);

/* Wrappers around the leb128 reader routines to simplify them for our
   purposes.  */

static inline const gdb_byte *
gdb_read_uleb128 (const gdb_byte *buf, const gdb_byte *buf_end,
		  uint64_t *r)
{
  size_t bytes_read = read_uleb128_to_uint64 (buf, buf_end, r);

  if (bytes_read == 0)
    return NULL;
  return buf + bytes_read;
}

static inline const gdb_byte *
gdb_read_sleb128 (const gdb_byte *buf, const gdb_byte *buf_end,
		  int64_t *r)
{
  size_t bytes_read = read_sleb128_to_int64 (buf, buf_end, r);

  if (bytes_read == 0)
    return NULL;
  return buf + bytes_read;
}

static inline const gdb_byte *
gdb_skip_leb128 (const gdb_byte *buf, const gdb_byte *buf_end)
{
  size_t bytes_read = skip_leb128 (buf, buf_end);

  if (bytes_read == 0)
    return NULL;
  return buf + bytes_read;
}

extern const gdb_byte *safe_read_uleb128 (const gdb_byte *buf,
					  const gdb_byte *buf_end,
					  uint64_t *r);

extern const gdb_byte *safe_read_sleb128 (const gdb_byte *buf,
					  const gdb_byte *buf_end,
					  int64_t *r);

extern const gdb_byte *safe_skip_leb128 (const gdb_byte *buf,
					 const gdb_byte *buf_end);

#endif /* dwarf2expr.h */
Commit	Line	Data
852483bc MK	1	/* DWARF 2 Expression Evaluator.
852483bc MK	2
618f726f	3	Copyright (C) 2001-2016 Free Software Foundation, Inc.
852483bc MK	4
	5	Contributed by Daniel Berlin <dan@dberlin.org>.
	6
4c2df51b DJ	7	This file is part of GDB.
	8
	9	This program is free software; you can redistribute it and/or modify
	10	it under the terms of the GNU General Public License as published by
a9762ec7	11	the Free Software Foundation; either version 3 of the License, or
4c2df51b DJ	12	(at your option) any later version.
	13
	14	This program is distributed in the hope that it will be useful,
	15	but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	17	GNU General Public License for more details.
	18
	19	You should have received a copy of the GNU General Public License
a9762ec7	20	along with this program. If not, see <http://www.gnu.org/licenses/>. */
4c2df51b DJ	21
	22	#if !defined (DWARF2EXPR_H)
	23	#define DWARF2EXPR_H
	24
f664829e	25	#include "leb128.h"
836bf454	26	#include "gdbtypes.h"
f664829e	27
cec03d70 TT	28	/* The location of a value. */
	29	enum dwarf_value_location
	30	{
44353522 DE	31	/* The piece is in memory.
44353522 DE	32	The value on the dwarf stack is its address. */
cec03d70	33	DWARF_VALUE_MEMORY,
44353522 DE	34
	35	/* The piece is in a register.
	36	The value on the dwarf stack is the register number. */
cec03d70	37	DWARF_VALUE_REGISTER,
44353522 DE	38
44353522 DE	39	/* The piece is on the dwarf stack. */
cec03d70	40	DWARF_VALUE_STACK,
44353522	41
cec03d70	42	/* The piece is a literal. */
cb826367 TT	43	DWARF_VALUE_LITERAL,
	44
	45	/* The piece was optimized out. */
8cf6f0b1 TT	46	DWARF_VALUE_OPTIMIZED_OUT,
	47
	48	/* The piece is an implicit pointer. */
	49	DWARF_VALUE_IMPLICIT_POINTER
cec03d70 TT	50	};
cec03d70 TT	51
44353522 DE	52	/* The dwarf expression stack. */
	53
	54	struct dwarf_stack_value
	55	{
8a9b8146	56	struct value *value;
44353522 DE	57
	58	/* Non-zero if the piece is in memory and is known to be
	59	on the program's stack. It is always ok to set this to zero.
	60	This is used, for example, to optimize memory access from the target.
	61	It can vastly speed up backtraces on long latency connections when
	62	"set stack-cache on". */
	63	int in_stack_memory;
	64	};
	65
4c2df51b DJ	66	/* The expression evaluator works with a dwarf_expr_context, describing
	67	its current state and its callbacks. */
	68	struct dwarf_expr_context
	69	{
718b9626 TT	70	dwarf_expr_context ();
	71	~dwarf_expr_context ();
	72
595d2e30 TT	73	void push_address (CORE_ADDR value, int in_stack_memory);
	74	void eval (const gdb_byte *addr, size_t len);
	75	struct value *fetch (int n);
	76	CORE_ADDR fetch_address (int n);
	77	int fetch_in_stack_memory (int n);
	78
4c2df51b	79	/* The stack of values, allocated with xmalloc. */
44353522	80	struct dwarf_stack_value *stack;
4c2df51b DJ	81
	82	/* The number of values currently pushed on the stack, and the
	83	number of elements allocated to the stack. */
	84	int stack_len, stack_allocated;
	85
f7fd4728 UW	86	/* Target architecture to use for address operations. */
	87	struct gdbarch *gdbarch;
	88
ae0d2f24 UW	89	/* Target address size in bytes. */
	90	int addr_size;
	91
181cebd4 JK	92	/* DW_FORM_ref_addr size in bytes. If -1 DWARF is executed from a frame
	93	context and operations depending on DW_FORM_ref_addr are not allowed. */
	94	int ref_addr_size;
	95
49f6c839	96	/* Offset used to relocate DW_OP_addr and DW_OP_GNU_addr_index arguments. */
ac56253d TT	97	CORE_ADDR offset;
ac56253d TT	98
4c2df51b DJ	99	/* The current depth of dwarf expression recursion, via DW_OP_call*,
	100	DW_OP_fbreg, DW_OP_push_object_address, etc., and the maximum
	101	depth we'll tolerate before raising an error. */
	102	int recursion_depth, max_recursion_depth;
	103
cec03d70 TT	104	/* Location of the value. */
	105	enum dwarf_value_location location;
	106
766062f6	107	/* For DWARF_VALUE_LITERAL, the current literal value's length and
8cf6f0b1	108	data. For DWARF_VALUE_IMPLICIT_POINTER, LEN is the offset of the
8b9737bf	109	target DIE of sect_offset kind. */
cec03d70	110	ULONGEST len;
0d45f56e	111	const gdb_byte *data;
87808bd6	112
42be36b3 CT	113	/* Initialization status of variable: Non-zero if variable has been
	114	initialized; zero otherwise. */
	115	int initialized;
	116
87808bd6 JB	117	/* An array of pieces. PIECES points to its first element;
	118	NUM_PIECES is its length.
	119
	120	Each time DW_OP_piece is executed, we add a new element to the
	121	end of this array, recording the current top of the stack, the
cec03d70	122	current location, and the size given as the operand to
44353522	123	DW_OP_piece. We then pop the top value from the stack, reset the
cec03d70	124	location, and resume evaluation.
87808bd6 JB	125
	126	The Dwarf spec doesn't say whether DW_OP_piece pops the top value
	127	from the stack. We do, ensuring that clients of this interface
	128	expecting to see a value left on the top of the stack (say, code
	129	evaluating frame base expressions or CFA's specified with
	130	DW_CFA_def_cfa_expression) will get an error if the expression
	131	actually marks all the values it computes as pieces.
	132
	133	If an expression never uses DW_OP_piece, num_pieces will be zero.
	134	(It would be nice to present these cases as expressions yielding
cec03d70 TT	135	a single piece, so that callers need not distinguish between the
	136	no-DW_OP_piece and one-DW_OP_piece cases. But expressions with
	137	no DW_OP_piece operations have no value to place in a piece's
	138	'size' field; the size comes from the surrounding data. So the
	139	two cases need to be handled separately.) */
87808bd6 JB	140	int num_pieces;
87808bd6 JB	141	struct dwarf_expr_piece *pieces;
595d2e30	142
192ca6d8 TT	143	/* Return the value of register number REGNUM (a DWARF register number),
	144	read as an address. */
	145	virtual CORE_ADDR read_addr_from_reg (int regnum) = 0;
	146
	147	/* Return a value of type TYPE, stored in register number REGNUM
	148	of the frame associated to the given BATON.
	149
	150	REGNUM is a DWARF register number. */
	151	virtual struct value get_reg_value (struct type type, int regnum) = 0;
	152
	153	/* Read LENGTH bytes at ADDR into BUF. */
	154	virtual void read_mem (gdb_byte *buf, CORE_ADDR addr, size_t length) = 0;
	155
	156	/* Return the location expression for the frame base attribute, in
	157	START and LENGTH. The result must be live until the current
	158	expression evaluation is complete. */
	159	virtual void get_frame_base (const gdb_byte *start, size_t length)
	160	{
	161	error (_("%s is invalid in this context"), "DW_OP_fbreg");
	162	}
	163
	164	/* Return the CFA for the frame. */
	165	virtual CORE_ADDR get_frame_cfa ()
	166	{
	167	error (_("%s is invalid in this context"), "DW_OP_call_frame_cfa");
	168	}
	169
	170	/* Return the PC for the frame. */
	171	virtual CORE_ADDR get_frame_pc ()
	172	{
	173	error (_("%s is invalid in this context"), "DW_OP_GNU_implicit_pointer");
	174	}
	175
	176	/* Return the thread-local storage address for
	177	DW_OP_GNU_push_tls_address or DW_OP_form_tls_address. */
	178	virtual CORE_ADDR get_tls_address (CORE_ADDR offset)
	179	{
	180	error (_("%s is invalid in this context"), "DW_OP_form_tls_address");
	181	}
	182
	183	/* Execute DW_AT_location expression for the DWARF expression
	184	subroutine in the DIE at DIE_OFFSET in the CU. Do not touch
	185	STACK while it being passed to and returned from the called DWARF
	186	subroutine. */
	187	virtual void dwarf_call (cu_offset die_offset)
	188	{
	189	error (_("%s is invalid in this context"), "DW_OP_call*");
	190	}
	191
	192	/* Return the base type given by the indicated DIE. This can throw
	193	an exception if the DIE is invalid or does not represent a base
	194	type. If can also be NULL in the special case where the
	195	callbacks are not performing evaluation, and thus it is
	196	meaningful to substitute a stub type of the correct size. */
	197	virtual struct type *impl_get_base_type (cu_offset die)
	198	{
	199	/* Anything will do. */
	200	return builtin_type (this->gdbarch)->builtin_int;
	201	}
	202
	203	/* Push on DWARF stack an entry evaluated for DW_TAG_GNU_call_site's
	204	parameter matching KIND and KIND_U at the caller of specified BATON.
	205	If DEREF_SIZE is not -1 then use DW_AT_GNU_call_site_data_value instead of
	206	DW_AT_GNU_call_site_value. */
207	virtual void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind,
208	union call_site_parameter_u kind_u,
209	int deref_size)
210	{
211	internal_error (__FILE__, __LINE__,
212	_("Support for DW_OP_GNU_entry_value is unimplemented"));
213	}
214
215	/* Return the address indexed by DW_OP_GNU_addr_index.
216	This can throw an exception if the index is out of range. */
217	virtual CORE_ADDR get_addr_index (unsigned int index)
218	{
219	error (_("%s is invalid in this context"), "DW_OP_GNU_addr_index");
220	}
221
222	/* Return the `object address' for DW_OP_push_object_address. */
223	virtual CORE_ADDR get_object_address ()
224	{
225	internal_error (__FILE__, __LINE__,
226	_("Support for DW_OP_push_object_address "
227	"is unimplemented"));
228	}
229
595d2e30 TT	230	private:
	231
	232	struct type *address_type () const;
	233	void grow_stack (size_t need);
	234	void push (struct value *value, int in_stack_memory);
	235	int stack_empty_p () const;
	236	void add_piece (ULONGEST size, ULONGEST offset);
	237	struct type *get_base_type (cu_offset die, int size);
	238	void execute_stack_op (const gdb_byte op_ptr, const gdb_byte op_end);
	239	void pop ();
87808bd6 JB	240	};
	241
	242
d3b1e874	243	/* A piece of an object, as recorded by DW_OP_piece or DW_OP_bit_piece. */
87808bd6 JB	244	struct dwarf_expr_piece
87808bd6 JB	245	{
cec03d70 TT	246	enum dwarf_value_location location;
	247
	248	union
	249	{
44353522 DE	250	struct
44353522 DE	251	{
f2c7657e UW	252	/* This piece's address, for DWARF_VALUE_MEMORY pieces. */
f2c7657e UW	253	CORE_ADDR addr;
44353522 DE	254	/* Non-zero if the piece is known to be in memory and on
	255	the program's stack. */
	256	int in_stack_memory;
f2c7657e UW	257	} mem;
f2c7657e UW	258
8a9b8146 TT	259	/* The piece's register number, for DWARF_VALUE_REGISTER pieces. */
	260	int regno;
	261
	262	/* The piece's literal value, for DWARF_VALUE_STACK pieces. */
	263	struct value *value;
cec03d70 TT	264
	265	struct
	266	{
f2c7657e UW	267	/* A pointer to the data making up this piece,
f2c7657e UW	268	for DWARF_VALUE_LITERAL pieces. */
0d45f56e	269	const gdb_byte *data;
cec03d70 TT	270	/* The length of the available data. */
	271	ULONGEST length;
	272	} literal;
8cf6f0b1 TT	273
	274	/* Used for DWARF_VALUE_IMPLICIT_POINTER. */
	275	struct
	276	{
	277	/* The referent DIE from DW_OP_GNU_implicit_pointer. */
8b9737bf	278	sect_offset die;
8cf6f0b1 TT	279	/* The byte offset into the resulting data. */
	280	LONGEST offset;
	281	} ptr;
cec03d70	282	} v;
87808bd6	283
d3b1e874	284	/* The length of the piece, in bits. */
87808bd6	285	ULONGEST size;
d3b1e874 TT	286	/* The piece offset, in bits. */
d3b1e874 TT	287	ULONGEST offset;
4c2df51b DJ	288	};
4c2df51b DJ	289
3cf03773 TT	290	void dwarf_expr_require_composition (const gdb_byte , const gdb_byte ,
	291	const char *);
	292
8e3b41a9	293	int dwarf_block_to_dwarf_reg (const gdb_byte buf, const gdb_byte buf_end);
523f3620	294
a471c594 JK	295	int dwarf_block_to_dwarf_reg_deref (const gdb_byte *buf,
	296	const gdb_byte *buf_end,
	297	CORE_ADDR *deref_size_return);
	298
e18b2753 JK	299	int dwarf_block_to_fb_offset (const gdb_byte buf, const gdb_byte buf_end,
	300	CORE_ADDR *fb_offset_return);
	301
	302	int dwarf_block_to_sp_offset (struct gdbarch gdbarch, const gdb_byte buf,
	303	const gdb_byte *buf_end,
	304	CORE_ADDR *sp_offset_return);
	305
f664829e DE	306	/* Wrappers around the leb128 reader routines to simplify them for our
	307	purposes. */
	308
	309	static inline const gdb_byte *
	310	gdb_read_uleb128 (const gdb_byte buf, const gdb_byte buf_end,
9fccedf7	311	uint64_t *r)
f664829e	312	{
9fccedf7	313	size_t bytes_read = read_uleb128_to_uint64 (buf, buf_end, r);
f664829e DE	314
	315	if (bytes_read == 0)
	316	return NULL;
	317	return buf + bytes_read;
	318	}
	319
	320	static inline const gdb_byte *
	321	gdb_read_sleb128 (const gdb_byte buf, const gdb_byte buf_end,
9fccedf7	322	int64_t *r)
f664829e	323	{
9fccedf7	324	size_t bytes_read = read_sleb128_to_int64 (buf, buf_end, r);
f664829e DE	325
	326	if (bytes_read == 0)
	327	return NULL;
	328	return buf + bytes_read;
	329	}
	330
	331	static inline const gdb_byte *
	332	gdb_skip_leb128 (const gdb_byte buf, const gdb_byte buf_end)
	333	{
	334	size_t bytes_read = skip_leb128 (buf, buf_end);
	335
	336	if (bytes_read == 0)
	337	return NULL;
	338	return buf + bytes_read;
	339	}
	340
	341	extern const gdb_byte safe_read_uleb128 (const gdb_byte buf,
	342	const gdb_byte *buf_end,
9fccedf7	343	uint64_t *r);
f664829e DE	344
	345	extern const gdb_byte safe_read_sleb128 (const gdb_byte buf,
	346	const gdb_byte *buf_end,
9fccedf7	347	int64_t *r);
f664829e DE	348
	349	extern const gdb_byte safe_skip_leb128 (const gdb_byte buf,
	350	const gdb_byte *buf_end);
	351
852483bc	352	#endif /* dwarf2expr.h */