[binutils.git] / gdb / inline-frame.c

/* Inline frame unwinder for GDB.

   Copyright (C) 2008, 2009, 2010, 2011 Free Software Foundation, Inc.

   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/>.  */

#include "defs.h"
#include "addrmap.h"
#include "block.h"
#include "frame-unwind.h"
#include "inferior.h"
#include "regcache.h"
#include "symtab.h"
#include "vec.h"

#include "gdb_assert.h"

/* We need to save a few variables for every thread stopped at the
   virtual call site of an inlined function.  If there was always a
   "struct thread_info", we could hang it off that; in the mean time,
   keep our own list.  */
struct inline_state
{
  /* The thread this data relates to.  It should be a currently
     stopped thread; we assume thread IDs never change while the
     thread is stopped.  */
  ptid_t ptid;

  /* The number of inlined functions we are skipping.  Each of these
     functions can be stepped in to.  */
  int skipped_frames;

  /* Only valid if SKIPPED_FRAMES is non-zero.  This is the PC used
     when calculating SKIPPED_FRAMES; used to check whether we have
     moved to a new location by user request.  If so, we invalidate
     any skipped frames.  */
  CORE_ADDR saved_pc;

  /* Only valid if SKIPPED_FRAMES is non-zero.  This is the symbol
     of the outermost skipped inline function.  It's used to find the
     call site of the current frame.  */
  struct symbol *skipped_symbol;
};

typedef struct inline_state inline_state_s;
DEF_VEC_O(inline_state_s);

static VEC(inline_state_s) *inline_states;

/* Locate saved inlined frame state for PTID, if it exists
   and is valid.  */

static struct inline_state *
find_inline_frame_state (ptid_t ptid)
{
  struct inline_state *state;
  int ix;

  for (ix = 0; VEC_iterate (inline_state_s, inline_states, ix, state); ix++)
    {
      if (ptid_equal (state->ptid, ptid))
	{
	  struct regcache *regcache = get_thread_regcache (ptid);
	  CORE_ADDR current_pc = regcache_read_pc (regcache);

	  if (current_pc != state->saved_pc)
	    {
	      /* PC has changed - this context is invalid.  Use the
		 default behavior.  */
	      VEC_unordered_remove (inline_state_s, inline_states, ix);
	      return NULL;
	    }
	  else
	    return state;
	}
    }

  return NULL;
}

/* Allocate saved inlined frame state for PTID.  */

static struct inline_state *
allocate_inline_frame_state (ptid_t ptid)
{
  struct inline_state *state;

  state = VEC_safe_push (inline_state_s, inline_states, NULL);
  memset (state, 0, sizeof (*state));
  state->ptid = ptid;

  return state;
}

/* Forget about any hidden inlined functions in PTID, which is new or
   about to be resumed.  PTID may be minus_one_ptid (all processes)
   or a PID (all threads in this process).  */

void
clear_inline_frame_state (ptid_t ptid)
{
  struct inline_state *state;
  int ix;

  if (ptid_equal (ptid, minus_one_ptid))
    {
      VEC_free (inline_state_s, inline_states);
      return;
    }

  if (ptid_is_pid (ptid))
    {
      VEC (inline_state_s) *new_states = NULL;
      int pid = ptid_get_pid (ptid);

      for (ix = 0;
	   VEC_iterate (inline_state_s, inline_states, ix, state);
	   ix++)
	if (pid != ptid_get_pid (state->ptid))
	  VEC_safe_push (inline_state_s, new_states, state);
      VEC_free (inline_state_s, inline_states);
      inline_states = new_states;
      return;
    }

  for (ix = 0; VEC_iterate (inline_state_s, inline_states, ix, state); ix++)
    if (ptid_equal (state->ptid, ptid))
      {
	VEC_unordered_remove (inline_state_s, inline_states, ix);
	return;
      }
}

static void
inline_frame_this_id (struct frame_info *this_frame,
		      void **this_cache,
		      struct frame_id *this_id)
{
  struct symbol *func;

  /* In order to have a stable frame ID for a given inline function,
     we must get the stack / special addresses from the underlying
     real frame's this_id method.  So we must call get_prev_frame.
     Because we are inlined into some function, there must be previous
     frames, so this is safe - as long as we're careful not to
     create any cycles.  */
  *this_id = get_frame_id (get_prev_frame (this_frame));

  /* We need a valid frame ID, so we need to be based on a valid
     frame.  FSF submission NOTE: this would be a good assertion to
     apply to all frames, all the time.  That would fix the ambiguity
     of null_frame_id (between "no/any frame" and "the outermost
     frame").  This will take work.  */
  gdb_assert (frame_id_p (*this_id));

  /* For now, require we don't match outer_frame_id either (see
     comment above).  */
  gdb_assert (!frame_id_eq (*this_id, outer_frame_id));

  /* Future work NOTE: Alexandre Oliva applied a patch to GCC 4.3
     which generates DW_AT_entry_pc for inlined functions when
     possible.  If this attribute is available, we should use it
     in the frame ID (and eventually, to set breakpoints).  */
  func = get_frame_function (this_frame);
  gdb_assert (func != NULL);
  (*this_id).code_addr = BLOCK_START (SYMBOL_BLOCK_VALUE (func));
  (*this_id).inline_depth++;
}

static struct value *
inline_frame_prev_register (struct frame_info *this_frame, void **this_cache,
			    int regnum)
{
  /* Use get_frame_register_value instead of
     frame_unwind_got_register, to avoid requiring this frame's ID.
     This frame's ID depends on the previous frame's ID (unusual), and
     the previous frame's ID depends on this frame's unwound
     registers.  If unwinding registers from this frame called
     get_frame_id, there would be a loop.

     Do not copy this code into any other unwinder!  Inlined functions
     are special; other unwinders must not have a dependency on the
     previous frame's ID, and therefore can and should use
     frame_unwind_got_register instead.  */
  return get_frame_register_value (this_frame, regnum);
}

/* Check whether we are at an inlining site that does not already
   have an associated frame.  */

static int
inline_frame_sniffer (const struct frame_unwind *self,
		      struct frame_info *this_frame,
		      void **this_cache)
{
  CORE_ADDR this_pc;
  struct block *frame_block, *cur_block;
  int depth;
  struct frame_info *next_frame;
  struct inline_state *state = find_inline_frame_state (inferior_ptid);

  this_pc = get_frame_address_in_block (this_frame);
  frame_block = block_for_pc (this_pc);
  if (frame_block == NULL)
    return 0;

  /* Calculate DEPTH, the number of inlined functions at this
     location.  */
  depth = 0;
  cur_block = frame_block;
  while (BLOCK_SUPERBLOCK (cur_block))
    {
      if (block_inlined_p (cur_block))
	depth++;

      cur_block = BLOCK_SUPERBLOCK (cur_block);
    }

  /* Check how many inlined functions already have frames.  */
  for (next_frame = get_next_frame (this_frame);
       next_frame && get_frame_type (next_frame) == INLINE_FRAME;
       next_frame = get_next_frame (next_frame))
    {
      gdb_assert (depth > 0);
      depth--;
    }

  /* If this is the topmost frame, or all frames above us are inlined,
     then check whether we were requested to skip some frames (so they
     can be stepped into later).  */
  if (state != NULL && state->skipped_frames > 0 && next_frame == NULL)
    {
      gdb_assert (depth >= state->skipped_frames);
      depth -= state->skipped_frames;
    }

  /* If all the inlined functions here already have frames, then pass
     to the normal unwinder for this PC.  */
  if (depth == 0)
    return 0;

  /* If the next frame is an inlined function, but not the outermost, then
     we are the next outer.  If it is not an inlined function, then we
     are the innermost inlined function of a different real frame.  */
  return 1;
}

const struct frame_unwind inline_frame_unwind = {
  INLINE_FRAME,
  inline_frame_this_id,
  inline_frame_prev_register,
  NULL,
  inline_frame_sniffer
};

/* Return non-zero if BLOCK, an inlined function block containing PC,
   has a group of contiguous instructions starting at PC (but not
   before it).  */

static int
block_starting_point_at (CORE_ADDR pc, struct block *block)
{
  struct blockvector *bv;
  struct block *new_block;

  bv = blockvector_for_pc (pc, NULL);
  if (BLOCKVECTOR_MAP (bv) == NULL)
    return 0;

  new_block = addrmap_find (BLOCKVECTOR_MAP (bv), pc - 1);
  if (new_block == NULL)
    return 1;

  if (new_block == block || contained_in (new_block, block))
    return 0;

  /* The immediately preceeding address belongs to a different block,
     which is not a child of this one.  Treat this as an entrance into
     BLOCK.  */
  return 1;
}

/* Skip all inlined functions whose call sites are at the current PC.
   Frames for the hidden functions will not appear in the backtrace until the
   user steps into them.  */

void
skip_inline_frames (ptid_t ptid)
{
  CORE_ADDR this_pc;
  struct block *frame_block, *cur_block;
  struct symbol *last_sym = NULL;
  int skip_count = 0;
  struct inline_state *state;

  /* This function is called right after reinitializing the frame
     cache.  We try not to do more unwinding than absolutely
     necessary, for performance.  */
  this_pc = get_frame_pc (get_current_frame ());
  frame_block = block_for_pc (this_pc);

  if (frame_block != NULL)
    {
      cur_block = frame_block;
      while (BLOCK_SUPERBLOCK (cur_block))
	{
	  if (block_inlined_p (cur_block))
	    {
	      /* See comments in inline_frame_this_id about this use
		 of BLOCK_START.  */
	      if (BLOCK_START (cur_block) == this_pc
		  || block_starting_point_at (this_pc, cur_block))
		{
		  skip_count++;
		  last_sym = BLOCK_FUNCTION (cur_block);
		}
	      else
		break;
	    }
	  cur_block = BLOCK_SUPERBLOCK (cur_block);
	}
    }

  gdb_assert (find_inline_frame_state (ptid) == NULL);
  state = allocate_inline_frame_state (ptid);
  state->skipped_frames = skip_count;
  state->saved_pc = this_pc;
  state->skipped_symbol = last_sym;

  if (skip_count != 0)
    reinit_frame_cache ();
}

/* Step into an inlined function by unhiding it.  */

void
step_into_inline_frame (ptid_t ptid)
{
  struct inline_state *state = find_inline_frame_state (ptid);

  gdb_assert (state != NULL && state->skipped_frames > 0);
  state->skipped_frames--;
  reinit_frame_cache ();
}

/* Return the number of hidden functions inlined into the current
   frame.  */

int
inline_skipped_frames (ptid_t ptid)
{
  struct inline_state *state = find_inline_frame_state (ptid);

  if (state == NULL)
    return 0;
  else
    return state->skipped_frames;
}

/* If one or more inlined functions are hidden, return the symbol for
   the function inlined into the current frame.  */

struct symbol *
inline_skipped_symbol (ptid_t ptid)
{
  struct inline_state *state = find_inline_frame_state (ptid);

  gdb_assert (state != NULL);
  return state->skipped_symbol;
}

/* Return the number of functions inlined into THIS_FRAME.  Some of
   the callees may not have associated frames (see
   skip_inline_frames).  */

int
frame_inlined_callees (struct frame_info *this_frame)
{
  struct frame_info *next_frame;
  int inline_count = 0;

  /* First count how many inlined functions at this PC have frames
     above FRAME (are inlined into FRAME).  */
  for (next_frame = get_next_frame (this_frame);
       next_frame && get_frame_type (next_frame) == INLINE_FRAME;
       next_frame = get_next_frame (next_frame))
    inline_count++;

  /* Simulate some most-inner inlined frames which were suppressed, so
     they can be stepped into later.  If we are unwinding already
     outer frames from some non-inlined frame this does not apply.  */
  if (next_frame == NULL)
    inline_count += inline_skipped_frames (inferior_ptid);

  return inline_count;
}
Commit	Line	Data
edb3359d DJ	1	/* Inline frame unwinder for GDB.
edb3359d DJ	2
7b6bb8da	3	Copyright (C) 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
edb3359d DJ	4
	5	This file is part of GDB.
	6
	7	This program is free software; you can redistribute it and/or modify
	8	it under the terms of the GNU General Public License as published by
	9	the Free Software Foundation; either version 3 of the License, or
	10	(at your option) any later version.
	11
	12	This program is distributed in the hope that it will be useful,
	13	but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	GNU General Public License for more details.
	16
	17	You should have received a copy of the GNU General Public License
	18	along with this program. If not, see <http://www.gnu.org/licenses/>. */
	19
	20	#include "defs.h"
	21	#include "addrmap.h"
	22	#include "block.h"
	23	#include "frame-unwind.h"
	24	#include "inferior.h"
4e485129	25	#include "regcache.h"
edb3359d DJ	26	#include "symtab.h"
	27	#include "vec.h"
	28
	29	#include "gdb_assert.h"
	30
	31	/* We need to save a few variables for every thread stopped at the
	32	virtual call site of an inlined function. If there was always a
	33	"struct thread_info", we could hang it off that; in the mean time,
	34	keep our own list. */
	35	struct inline_state
	36	{
	37	/* The thread this data relates to. It should be a currently
	38	stopped thread; we assume thread IDs never change while the
	39	thread is stopped. */
	40	ptid_t ptid;
	41
	42	/* The number of inlined functions we are skipping. Each of these
	43	functions can be stepped in to. */
	44	int skipped_frames;
	45
	46	/* Only valid if SKIPPED_FRAMES is non-zero. This is the PC used
	47	when calculating SKIPPED_FRAMES; used to check whether we have
	48	moved to a new location by user request. If so, we invalidate
	49	any skipped frames. */
	50	CORE_ADDR saved_pc;
	51
	52	/* Only valid if SKIPPED_FRAMES is non-zero. This is the symbol
	53	of the outermost skipped inline function. It's used to find the
	54	call site of the current frame. */
	55	struct symbol *skipped_symbol;
	56	};
	57
	58	typedef struct inline_state inline_state_s;
	59	DEF_VEC_O(inline_state_s);
	60
	61	static VEC(inline_state_s) *inline_states;
	62
4e485129 DJ	63	/* Locate saved inlined frame state for PTID, if it exists
4e485129 DJ	64	and is valid. */
edb3359d DJ	65
	66	static struct inline_state *
	67	find_inline_frame_state (ptid_t ptid)
	68	{
	69	struct inline_state *state;
	70	int ix;
	71
	72	for (ix = 0; VEC_iterate (inline_state_s, inline_states, ix, state); ix++)
	73	{
	74	if (ptid_equal (state->ptid, ptid))
4e485129 DJ	75	{
	76	struct regcache *regcache = get_thread_regcache (ptid);
	77	CORE_ADDR current_pc = regcache_read_pc (regcache);
abbb1732	78
4e485129 DJ	79	if (current_pc != state->saved_pc)
	80	{
	81	/* PC has changed - this context is invalid. Use the
	82	default behavior. */
	83	VEC_unordered_remove (inline_state_s, inline_states, ix);
	84	return NULL;
	85	}
	86	else
	87	return state;
	88	}
edb3359d DJ	89	}
	90
	91	return NULL;
	92	}
	93
	94	/* Allocate saved inlined frame state for PTID. */
	95
	96	static struct inline_state *
	97	allocate_inline_frame_state (ptid_t ptid)
	98	{
	99	struct inline_state *state;
	100
	101	state = VEC_safe_push (inline_state_s, inline_states, NULL);
	102	memset (state, 0, sizeof (*state));
	103	state->ptid = ptid;
	104
	105	return state;
	106	}
	107
	108	/* Forget about any hidden inlined functions in PTID, which is new or
	109	about to be resumed. PTID may be minus_one_ptid (all processes)
	110	or a PID (all threads in this process). */
	111
	112	void
	113	clear_inline_frame_state (ptid_t ptid)
	114	{
	115	struct inline_state *state;
	116	int ix;
	117
	118	if (ptid_equal (ptid, minus_one_ptid))
	119	{
	120	VEC_free (inline_state_s, inline_states);
	121	return;
	122	}
	123
	124	if (ptid_is_pid (ptid))
	125	{
	126	VEC (inline_state_s) *new_states = NULL;
	127	int pid = ptid_get_pid (ptid);
abbb1732	128
3e43a32a MS	129	for (ix = 0;
	130	VEC_iterate (inline_state_s, inline_states, ix, state);
	131	ix++)
edb3359d DJ	132	if (pid != ptid_get_pid (state->ptid))
	133	VEC_safe_push (inline_state_s, new_states, state);
	134	VEC_free (inline_state_s, inline_states);
	135	inline_states = new_states;
	136	return;
	137	}
	138
	139	for (ix = 0; VEC_iterate (inline_state_s, inline_states, ix, state); ix++)
	140	if (ptid_equal (state->ptid, ptid))
	141	{
	142	VEC_unordered_remove (inline_state_s, inline_states, ix);
	143	return;
	144	}
	145	}
	146
	147	static void
	148	inline_frame_this_id (struct frame_info *this_frame,
	149	void **this_cache,
	150	struct frame_id *this_id)
	151	{
	152	struct symbol *func;
	153
	154	/* In order to have a stable frame ID for a given inline function,
	155	we must get the stack / special addresses from the underlying
	156	real frame's this_id method. So we must call get_prev_frame.
	157	Because we are inlined into some function, there must be previous
	158	frames, so this is safe - as long as we're careful not to
	159	create any cycles. */
	160	*this_id = get_frame_id (get_prev_frame (this_frame));
	161
	162	/* We need a valid frame ID, so we need to be based on a valid
	163	frame. FSF submission NOTE: this would be a good assertion to
	164	apply to all frames, all the time. That would fix the ambiguity
	165	of null_frame_id (between "no/any frame" and "the outermost
	166	frame"). This will take work. */
	167	gdb_assert (frame_id_p (*this_id));
	168
005ca36a JB	169	/* For now, require we don't match outer_frame_id either (see
	170	comment above). */
	171	gdb_assert (!frame_id_eq (*this_id, outer_frame_id));
	172
edb3359d DJ	173	/* Future work NOTE: Alexandre Oliva applied a patch to GCC 4.3
	174	which generates DW_AT_entry_pc for inlined functions when
	175	possible. If this attribute is available, we should use it
	176	in the frame ID (and eventually, to set breakpoints). */
	177	func = get_frame_function (this_frame);
	178	gdb_assert (func != NULL);
	179	(*this_id).code_addr = BLOCK_START (SYMBOL_BLOCK_VALUE (func));
	180	(*this_id).inline_depth++;
	181	}
	182
	183	static struct value *
	184	inline_frame_prev_register (struct frame_info this_frame, void *this_cache,
	185	int regnum)
	186	{
	187	/* Use get_frame_register_value instead of
	188	frame_unwind_got_register, to avoid requiring this frame's ID.
	189	This frame's ID depends on the previous frame's ID (unusual), and
	190	the previous frame's ID depends on this frame's unwound
	191	registers. If unwinding registers from this frame called
	192	get_frame_id, there would be a loop.
	193
	194	Do not copy this code into any other unwinder! Inlined functions
	195	are special; other unwinders must not have a dependency on the
	196	previous frame's ID, and therefore can and should use
	197	frame_unwind_got_register instead. */
	198	return get_frame_register_value (this_frame, regnum);
	199	}
	200
	201	/* Check whether we are at an inlining site that does not already
	202	have an associated frame. */
	203
	204	static int
	205	inline_frame_sniffer (const struct frame_unwind *self,
	206	struct frame_info *this_frame,
	207	void **this_cache)
	208	{
	209	CORE_ADDR this_pc;
	210	struct block frame_block, cur_block;
	211	int depth;
	212	struct frame_info *next_frame;
	213	struct inline_state *state = find_inline_frame_state (inferior_ptid);
	214
	215	this_pc = get_frame_address_in_block (this_frame);
	216	frame_block = block_for_pc (this_pc);
	217	if (frame_block == NULL)
	218	return 0;
	219
	220	/* Calculate DEPTH, the number of inlined functions at this
	221	location. */
	222	depth = 0;
	223	cur_block = frame_block;
	224	while (BLOCK_SUPERBLOCK (cur_block))
	225	{
	226	if (block_inlined_p (cur_block))
	227	depth++;
	228
	229	cur_block = BLOCK_SUPERBLOCK (cur_block);
	230	}
	231
	232	/* Check how many inlined functions already have frames. */
	233	for (next_frame = get_next_frame (this_frame);
	234	next_frame && get_frame_type (next_frame) == INLINE_FRAME;
	235	next_frame = get_next_frame (next_frame))
	236	{
237	gdb_assert (depth > 0);
238	depth--;
239	}
240
241	/* If this is the topmost frame, or all frames above us are inlined,
242	then check whether we were requested to skip some frames (so they
243	can be stepped into later). */
244	if (state != NULL && state->skipped_frames > 0 && next_frame == NULL)
245	{
4e485129 DJ	246	gdb_assert (depth >= state->skipped_frames);
4e485129 DJ	247	depth -= state->skipped_frames;
edb3359d DJ	248	}
	249
	250	/* If all the inlined functions here already have frames, then pass
	251	to the normal unwinder for this PC. */
	252	if (depth == 0)
	253	return 0;
	254
	255	/* If the next frame is an inlined function, but not the outermost, then
	256	we are the next outer. If it is not an inlined function, then we
	257	are the innermost inlined function of a different real frame. */
	258	return 1;
	259	}
	260
39d7b0e2	261	const struct frame_unwind inline_frame_unwind = {
edb3359d DJ	262	INLINE_FRAME,
	263	inline_frame_this_id,
	264	inline_frame_prev_register,
	265	NULL,
	266	inline_frame_sniffer
	267	};
	268
edb3359d DJ	269	/* Return non-zero if BLOCK, an inlined function block containing PC,
	270	has a group of contiguous instructions starting at PC (but not
	271	before it). */
	272
	273	static int
	274	block_starting_point_at (CORE_ADDR pc, struct block *block)
	275	{
	276	struct blockvector *bv;
	277	struct block *new_block;
	278
	279	bv = blockvector_for_pc (pc, NULL);
	280	if (BLOCKVECTOR_MAP (bv) == NULL)
	281	return 0;
	282
	283	new_block = addrmap_find (BLOCKVECTOR_MAP (bv), pc - 1);
	284	if (new_block == NULL)
	285	return 1;
	286
	287	if (new_block == block \|\| contained_in (new_block, block))
	288	return 0;
	289
	290	/* The immediately preceeding address belongs to a different block,
	291	which is not a child of this one. Treat this as an entrance into
	292	BLOCK. */
	293	return 1;
	294	}
	295
	296	/* Skip all inlined functions whose call sites are at the current PC.
	297	Frames for the hidden functions will not appear in the backtrace until the
	298	user steps into them. */
	299
	300	void
	301	skip_inline_frames (ptid_t ptid)
	302	{
	303	CORE_ADDR this_pc;
	304	struct block frame_block, cur_block;
	305	struct symbol *last_sym = NULL;
	306	int skip_count = 0;
	307	struct inline_state *state;
	308
	309	/* This function is called right after reinitializing the frame
	310	cache. We try not to do more unwinding than absolutely
	311	necessary, for performance. */
	312	this_pc = get_frame_pc (get_current_frame ());
	313	frame_block = block_for_pc (this_pc);
	314
	315	if (frame_block != NULL)
	316	{
	317	cur_block = frame_block;
	318	while (BLOCK_SUPERBLOCK (cur_block))
	319	{
	320	if (block_inlined_p (cur_block))
	321	{
	322	/* See comments in inline_frame_this_id about this use
	323	of BLOCK_START. */
	324	if (BLOCK_START (cur_block) == this_pc
	325	\|\| block_starting_point_at (this_pc, cur_block))
	326	{
	327	skip_count++;
	328	last_sym = BLOCK_FUNCTION (cur_block);
	329	}
	330	else
	331	break;
	332	}
333	cur_block = BLOCK_SUPERBLOCK (cur_block);
334	}
335	}
336
337	gdb_assert (find_inline_frame_state (ptid) == NULL);
338	state = allocate_inline_frame_state (ptid);
339	state->skipped_frames = skip_count;
340	state->saved_pc = this_pc;
341	state->skipped_symbol = last_sym;
342
343	if (skip_count != 0)
344	reinit_frame_cache ();
345	}
346
347	/* Step into an inlined function by unhiding it. */
348
349	void
350	step_into_inline_frame (ptid_t ptid)
351	{
352	struct inline_state *state = find_inline_frame_state (ptid);
353
354	gdb_assert (state != NULL && state->skipped_frames > 0);
355	state->skipped_frames--;
356	reinit_frame_cache ();
357	}
358
359	/* Return the number of hidden functions inlined into the current
360	frame. */
361
362	int
363	inline_skipped_frames (ptid_t ptid)
364	{
365	struct inline_state *state = find_inline_frame_state (ptid);
366
367	if (state == NULL)
368	return 0;
369	else
370	return state->skipped_frames;
371	}
372
373	/* If one or more inlined functions are hidden, return the symbol for
374	the function inlined into the current frame. */
375
376	struct symbol *
377	inline_skipped_symbol (ptid_t ptid)
378	{
379	struct inline_state *state = find_inline_frame_state (ptid);
380
381	gdb_assert (state != NULL);
382	return state->skipped_symbol;
383	}
384
385	/* Return the number of functions inlined into THIS_FRAME. Some of
386	the callees may not have associated frames (see
387	skip_inline_frames). */
388
389	int
390	frame_inlined_callees (struct frame_info *this_frame)
391	{
392	struct frame_info *next_frame;
393	int inline_count = 0;
394
395	/* First count how many inlined functions at this PC have frames
396	above FRAME (are inlined into FRAME). */
397	for (next_frame = get_next_frame (this_frame);
398	next_frame && get_frame_type (next_frame) == INLINE_FRAME;
399	next_frame = get_next_frame (next_frame))
400	inline_count++;
401
402	/* Simulate some most-inner inlined frames which were suppressed, so
403	they can be stepped into later. If we are unwinding already
404	outer frames from some non-inlined frame this does not apply. */
405	if (next_frame == NULL)
406	inline_count += inline_skipped_frames (inferior_ptid);
407
408	return inline_count;
409	}