#include "config.h"
#include "system.h"
#include "coretypes.h"

Include dependency graph for df-core.c:

Functions
static void *	df_get_bb_info (struct dataflow *, unsigned int)
static void	df_set_bb_info (struct dataflow , unsigned int, void )
static void	df_clear_bb_info (struct dataflow *, unsigned int)
static void	df_set_clean_cfg (void)
void	df_add_problem ()
int	df_set_flags ()
int	df_clear_flags ()
void	df_set_blocks ()
void	df_remove_problem ()
void	df_finish_pass ()
static unsigned int	rest_of_handle_df_initialize ()
static bool	gate_opt ()
rtl_opt_pass *	make_pass_df_initialize_opt ()
static bool	gate_no_opt ()
rtl_opt_pass *	make_pass_df_initialize_no_opt ()
static unsigned int	rest_of_handle_df_finish ()
rtl_opt_pass *	make_pass_df_finish ()
static bool	df_worklist_propagate_forward (struct dataflow dataflow, unsigned bb_index, unsigned bbindex_to_postorder, bitmap pending, sbitmap considered, ptrdiff_t age)
static bool	df_worklist_propagate_backward (struct dataflow dataflow, unsigned bb_index, unsigned bbindex_to_postorder, bitmap pending, sbitmap considered, ptrdiff_t age)
static void	df_worklist_dataflow_doublequeue (struct dataflow dataflow, bitmap pending, sbitmap considered, int blocks_in_postorder, unsigned *bbindex_to_postorder, int n_blocks)
void	df_worklist_dataflow (struct dataflow dataflow, bitmap blocks_to_consider, int blocks_in_postorder, int n_blocks)
static unsigned	df_prune_to_subcfg ()
void	df_analyze_problem (struct dataflow dflow, bitmap blocks_to_consider, int postorder, int n_blocks)
void	df_analyze ()
int	df_get_n_blocks ()
int *	df_get_postorder ()
void	df_simple_dataflow (enum df_flow_dir dir, df_init_function init_fun, df_confluence_function_0 con_fun_0, df_confluence_function_n con_fun_n, df_transfer_function trans_fun, bitmap blocks, int *postorder, int n_blocks)
static void *	df_get_bb_info ()
static void	df_clear_bb_info ()
void	df_mark_solutions_dirty ()
bool	df_get_bb_dirty ()
void	df_set_bb_dirty ()
void	df_grow_bb_info ()
static void	df_clear_bb_dirty ()
void	df_compact_blocks ()
void	df_bb_replace ()
void	df_bb_delete ()
void	df_verify ()
static int *	df_compute_cfg_image ()
void	df_check_cfg_clean ()
df_ref	df_bb_regno_first_def_find ()
df_ref	df_bb_regno_last_def_find ()
df_ref	df_find_def ()
bool	df_reg_defined ()
df_ref	df_find_use ()
bool	df_reg_used ()
void	dump_regset ()
void	debug_regset (regset)
DEBUG_FUNCTION void	debug_regset ()
void	df_print_regset ()
void	df_print_word_regset ()
void	df_dump ()
void	df_dump_region ()
void	df_dump_start ()
static void	df_dump_bb_problem_data ()
void	df_dump_top ()
void	df_dump_bottom ()
static void	df_dump_insn_problem_data ()
void	df_dump_insn_top ()
void	df_dump_insn_bottom ()
static void	df_ref_dump ()
void	df_refs_chain_dump ()
void	df_regs_chain_dump ()
static void	df_mws_dump ()
static void	df_insn_uid_debug (unsigned int uid, bool follow_chain, FILE *file)
DEBUG_FUNCTION void	df_insn_debug ()
DEBUG_FUNCTION void	df_insn_debug_regno ()
DEBUG_FUNCTION void	df_regno_debug ()
DEBUG_FUNCTION void	df_ref_debug ()
DEBUG_FUNCTION void	debug_df_insn ()
DEBUG_FUNCTION void	debug_df_reg ()
DEBUG_FUNCTION void	debug_df_regno ()
DEBUG_FUNCTION void	debug_df_ref ()
DEBUG_FUNCTION void	debug_df_defno ()
DEBUG_FUNCTION void	debug_df_useno ()
DEBUG_FUNCTION void	debug_df_chain ()

Variables
struct bitmap_obstack	reg_obstack
bitmap_obstack	df_bitmap_obstack
struct df_d *	df
static struct df_problem	user_problem
static struct dataflow	user_dflow
static int *	saved_cfg = NULL

Function Documentation

DEBUG_FUNCTION void debug_df_chain ( )

DEBUG_FUNCTION void debug_df_defno ( )

DEBUG_FUNCTION void debug_df_insn ( )

   Functions for debugging from GDB.

DEBUG_FUNCTION void debug_df_ref ( )

DEBUG_FUNCTION void debug_df_reg ( )

DEBUG_FUNCTION void debug_df_regno ( )

DEBUG_FUNCTION void debug_df_useno ( )

void debug_regset ( regset )

   Print a human-readable representation of R on the standard error
   stream.  This function is designed to be used from within the
   debugger.

DEBUG_FUNCTION void debug_regset ( )

References df_d::blocks_to_analyze, and df_dump_start().

void df_add_problem ( )

   Add PROBLEM (and any dependent problems) to the DF instance.

     First try to add the dependent problem.

     Check to see if this problem has already been defined.  If it
     has, just return that instance, if not, add it to the end of the
     vector.

     Make a new one and add it to the end.

     Keep the defined problems ordered by index.  This solves the
     problem that RI will use the information from UREC if UREC has
     been defined, or from LIVE if LIVE is defined and otherwise LR.
     However for this to work, the computation of RI must be pushed
     after which ever of those problems is defined, but we do not
     require any of those except for LR to have actually been
     defined.

Referenced by df_lr_verify_solution_end().

void df_analyze ( void )

   Analyze dataflow info for the basic blocks specified by the bitmap
   BLOCKS, or for the whole CFG if BLOCKS is zero.

     These should be the same.

     We need to do this before the df_verify_all because this is
     not kept incrementally up to date.

     Verify that POSTORDER_INVERTED only contains blocks reachable from
     the ENTRY block.

     Make sure that we have pruned any unreachable blocks from these
     sets.

     Skip over the DF_SCAN problem.

Referenced by compute_bb_for_insn(), copyprop_hardreg_forward(), dse_step4(), duplicate_computed_gotos(), mark_artificial_uses(), move_insn_for_shrink_wrap(), move_unallocated_pseudos(), and split_live_ranges_for_shrink_wrap().

void df_analyze_problem	(	struct dataflow *	dflow,
		bitmap	blocks_to_consider,
		int *	postorder,
		int	n_blocks
	)

@verbatim

Execute dataflow analysis on a single dataflow problem.

BLOCKS_TO_CONSIDER are the blocks whose solution can either be examined or will be computed. For calls from DF_ANALYZE, this is the set of blocks that has been passed to DF_SET_BLOCKS.

     (Re)Allocate the datastructures necessary to solve the problem.

     Set up the problem and compute the local information.

     Solve the equations.

     Massage the solution.

Referenced by fast_dce().

void df_bb_delete ( )

   Free all of the per basic block dataflow from all of the problems.
   This is typically called before a basic block is deleted and the
   problem will be reanalyzed.

References df_compute_cfg_image(), free(), and saved_cfg.

df_ref df_bb_regno_first_def_find ( )

   Return first def of REGNO within BB.

References df_d::changeable_flags, and DF_EQ_NOTES.

df_ref df_bb_regno_last_def_find ( )

   Return last def of REGNO within BB.

void df_bb_replace ( )

   Shove NEW_BLOCK in at OLD_INDEX.  Called from ifcvt to hack a
   block.  There is no excuse for people to do this kind of thing.

void df_check_cfg_clean ( void )

   This function compares the saved version of the cfg with the
   current cfg and aborts if the two are identical.  The function
   silently returns if the cfg has been marked as dirty or the two are
   the same.

static void df_clear_bb_dirty ( )

static

   Clear the dirty bits.  This is called from places that delete
   blocks.

static void df_clear_bb_info	(	struct dataflow *	,
		unsigned	int
	)

static

static void df_clear_bb_info ( )

static

   Clear basic block info.

int df_clear_flags ( )

   Clear the MASK flags in the DFLOW problem.  The old flags are
   returned.  If a flag is not allowed to be changed this will fail if
   checking is enabled.

References bitmap_print(), df_d::blocks_to_analyze, and dump_file.

Referenced by df_insn_rescan_debug_internal(), df_lr_confluence_0(), fast_dce(), and split_live_ranges_for_shrink_wrap().

void df_compact_blocks ( void )

   Called from the rtl_compact_blocks to reorganize the problems basic
   block info.

         Need to reorganize the out_of_date_transfer_functions for the
         dflow problem.

         Now shuffle the block info for the problem.

             Copy the bb info from the problem tmps to the proper
             place in the block_info vector.  Null out the copied
             item.  The entry and exit blocks never move.

     Shuffle the bits in the basic_block indexed arrays.

Referenced by unlink_block().

static int* df_compute_cfg_image ( )

static

   Compute an array of ints that describes the cfg.  This can be used
   to discover places where the cfg is modified by the appropriate
   calls have not been made to the keep df informed.  The internals of
   this are unexciting, the key is that two instances of this can be
   compared to see if any changes have been made to the cfg.

Referenced by df_bb_delete(), and df_verify().

void df_dump ( )

   Dump dataflow info.

Referenced by mark_artificial_uses().

static void df_dump_bb_problem_data ( )

static

   Dump the top or bottom of the block information for BB.

References df_chain_dump(), and df_ref_dump().

void df_dump_bottom ( )

   Dump the bottom of the block information for BB.

void df_dump_insn_bottom ( )

   Dump information about INSN after dumping INSN itself.

static void df_dump_insn_problem_data ( )

static

   Dump information about INSN just before or after dumping INSN itself.

References df_mws_dump(), and df_refs_chain_dump().

Referenced by df_dump_start().

void df_dump_insn_top ( )

   Dump information about INSN before dumping INSN itself.

References df_insn_uid_debug().

void df_dump_region ( )

   Dump dataflow info for df->blocks_to_analyze.

References dataflow::computed, df_problem::dump_insn_bottom_fun, df_problem::dump_insn_top_fun, df_d::num_problems_defined, dataflow::problem, and df_d::problems_in_order.

void df_dump_start ( )

   Dump the introductory information for each problem defined.

References df_dump_insn_problem_data().

Referenced by debug_regset().

void df_dump_top ( )

   Dump the top of the block information for BB.

Referenced by commit_one_edge_insertion().

df_ref df_find_def ( )

   Finds the reference corresponding to the definition of REG in INSN.
   DF is the dataflow object.

df_ref df_find_use ( )

   Finds the reference corresponding to the use of REG in INSN.
   DF is the dataflow object.

Referenced by invariant_for_use().

void df_finish_pass ( )

   Remove all of the problems that are not permanent.  Scanning, LR
   and (at -O2 or higher) LIVE are permanent, the rest are removable.
   Also clear all of the changeable_flags.

     Clear all of the flags.

     Set the focus back to the whole function.

     Verification will fail in DF_NO_INSN_RESCAN.

References df_problem::id, dataflow::optional_p, dataflow::problem, df_d::problems_by_index, df_d::problems_in_order, and df_problem::remove_problem_fun.

Referenced by biv_p(), and duplicate_computed_gotos().

bool df_get_bb_dirty ( )

   Return true if BB needs it's transfer functions recomputed.

References df_d::num_problems_defined, and df_d::problems_in_order.

static void* df_get_bb_info	(	struct dataflow *	,
		unsigned	int
	)

static

@verbatim

Allocation for dataflow support routines. Copyright (C) 1999-2013 Free Software Foundation, Inc. Originally contributed by Michael P. Hayes (m.hay.nosp@m.es@e.nosp@m.lec.c.nosp@m.ante.nosp@m.rbury.nosp@m..ac..nosp@m.nz, mhaye.nosp@m.s@re.nosp@m.dhat..nosp@m.com) Major rewrite contributed by Danny Berlin (dberl.nosp@m.in@d.nosp@m.berli.nosp@m.n.or.nosp@m.g) and Kenneth Zadeck (zadec.nosp@m.k@na.nosp@m.tural.nosp@m.brid.nosp@m.ge.co.nosp@m.m).

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/.

static void* df_get_bb_info ( )

static

   Get basic block info.

References bitmap_set_bit(), df_mark_solutions_dirty(), basic_block_def::flags, basic_block_def::index, df_d::num_problems_defined, dataflow::out_of_date_transfer_functions, and df_d::problems_in_order.

int df_get_n_blocks ( )

   Return the number of basic blocks from the last call to df_analyze.

References dataflow::block_info, df_problem::block_info_elt_size, dataflow::block_info_size, and dataflow::problem.

int* df_get_postorder ( )

   Return a pointer to the array of basic blocks in the reverse postorder.
   Depending on the direction of the dataflow problem,
   it returns either the usual reverse postorder array
   or the reverse postorder of inverted traversal.

References dataflow::block_info, df_problem::block_info_elt_size, memcpy(), and dataflow::problem.

void df_grow_bb_info ( )

   Grow the bb_info array.

References dataflow::block_info, df_problem::block_info_elt_size, df_set_bb_info(), free(), basic_block_def::index, memcpy(), memset(), and dataflow::problem.

DEBUG_FUNCTION void df_insn_debug ( )

DEBUG_FUNCTION void df_insn_debug_regno ( )

References df_chain_dump().

static void df_insn_uid_debug	(	unsigned int	uid,
		bool	follow_chain,
		FILE *	file
	)

static

Referenced by df_dump_insn_top().

void df_mark_solutions_dirty ( void )

   Mark the solutions as being out of date.

References bitmap_clear_bit(), basic_block_def::index, df_d::num_problems_defined, dataflow::out_of_date_transfer_functions, and df_d::problems_in_order.

Referenced by connect_dest(), create_check_block_twin(), and df_get_bb_info().

static void df_mws_dump ( )

static

Referenced by df_dump_insn_problem_data().

void df_print_regset ( )

   Write information about registers and basic blocks into FILE.
   This is part of making a debugging dump.

Referenced by df_live_confluence_n(), df_live_transfer_function(), df_lr_finalize(), df_lr_transfer_function(), df_remove_dead_eq_notes(), df_scan_free(), df_whole_mw_reg_dead_p(), and get_stored_val().

void df_print_word_regset ( )

   Write information about registers and basic blocks into FILE.  The
   bitmap is in the form used by df_byte_lr.  This is part of making a
   debugging dump.

References dataflow::computed, df_problem::dump_start_fun, dataflow::problem, and df_d::problems_in_order.

Referenced by df_word_lr_bb_local_compute(), and gate_ud_dce().

static unsigned df_prune_to_subcfg ( )

static

   Remove the entries not in BLOCKS from the LIST of length LEN, preserving
   the order of the remaining entries.  Returns the length of the resulting
   list.

DEBUG_FUNCTION void df_ref_debug ( )

Referenced by df_create_unused_note().

static void df_ref_dump ( )

static

Referenced by df_dump_bb_problem_data().

void df_refs_chain_dump ( )

References df_regs_chain_dump().

Referenced by df_dump_insn_problem_data().

bool df_reg_defined ( )

   Return true if REG is defined in INSN, zero otherwise.

bool df_reg_used ( )

   Return true if REG is referenced in INSN, zero otherwise.

DEBUG_FUNCTION void df_regno_debug ( )

void df_regs_chain_dump ( )

   Dump either a ref-def or reg-use chain.

Referenced by df_refs_chain_dump().

void df_remove_problem ( )

   Delete a DFLOW problem (and any problems that depend on this
   problem).

     Delete any problems that depended on this problem first.

     Now remove this problem.

References df_d::num_problems_defined, and df_d::problems_in_order.

Referenced by init_dce(), and split_live_ranges_for_shrink_wrap().

void df_set_bb_dirty ( )

   Mark BB as needing it's transfer functions as being out of
   date.

References bitmap_bit_p(), bitmap_clear(), bitmap_copy(), bitmap_set_bit(), basic_block_def::index, and dataflow::out_of_date_transfer_functions.

Referenced by cond_exec_find_if_block(), df_get_eh_block_artificial_uses(), df_grow_insn_info(), and fixup_partition_crossing().

static void df_set_bb_info	(	struct dataflow *	dflow,
		unsigned int	index,
		void *	bb_info
	)

static

   Set basic block info.

Referenced by df_grow_bb_info().

void df_set_blocks ( )

   Set the blocks that are to be considered for analysis.  If this is
   not called or is called with null, the entire function in
   analyzed.

             This block is called to change the focus from one subset
             to another.

             This block of code is executed to change the focus from
             the entire function to a subset.

         This block is executed to reset the focus to the entire
         function.

     Setting the blocks causes the refs to be unorganized since only
     the refs in the blocks are seen.

static void df_set_clean_cfg ( )

static

   This function builds a cfg fingerprint and squirrels it away in
   saved_cfg.

int df_set_flags ( )

   Set the MASK flags in the DFLOW problem.  The old flags are
   returned.  If a flag is not allowed to be changed this will fail if
   checking is enabled.

References df_d::changeable_flags.

Referenced by clear_iv_info(), df_insn_rescan_debug_internal(), df_lr_confluence_0(), dse_step4(), duplicate_computed_gotos(), fast_dce(), and mark_artificial_uses().

void df_simple_dataflow	(	enum df_flow_dir	dir,
		df_init_function	init_fun,
		df_confluence_function_0	con_fun_0,
		df_confluence_function_n	con_fun_n,
		df_transfer_function	trans_fun,
		bitmap	blocks,
		int *	postorder,
		int	n_blocks
	)

   Interface for calling iterative dataflow with user defined
   confluence and transfer functions.  All that is necessary is to
   supply DIR, a direction, CONF_FUN_0, a confluence function for
   blocks with no logical preds (or NULL), CONF_FUN_N, the normal
   confluence function, TRANS_FUN, the basic block transfer function,
   and BLOCKS, the set of blocks to examine, POSTORDER the blocks in
   postorder, and N_BLOCKS, the number of blocks in POSTORDER.

References df_d::num_problems_defined, df_d::problems_in_order, and dataflow::solutions_dirty.

void df_verify ( void )

   Verify that there is a place for everything and everything is in
   its place.  This is too expensive to run after every pass in the
   mainline.  However this is an excellent debugging tool if the
   dataflow information is not being updated properly.  You can just
   sprinkle calls in until you find the place that is changing an
   underlying structure without calling the proper updating
   routine.

References df_compute_cfg_image(), free(), and saved_cfg.

void df_worklist_dataflow	(	struct dataflow *	dataflow,
		bitmap	blocks_to_consider,
		int *	blocks_in_postorder,
		int	n_blocks
	)

   Worklist-based dataflow solver. It uses sbitmap as a worklist,
   with "n"-th bit representing the n-th block in the reverse-postorder order.
   The solver is a double-queue algorithm similar to the "double stack" solver
   from Cooper, Harvey and Kennedy, "Iterative data-flow analysis, Revisited".
   The only significant difference is that the worklist in this implementation
   is always sorted in RPO of the CFG visiting direction.

     BBINDEX_TO_POSTORDER maps the bb->index to the reverse postorder.

     Initialize the array to an out-of-bound value.

     Initialize the considered map.

     Initialize the mapping of block index to postorder.

         Add all blocks to the worklist.

     Initialize the problem.

     Solve it.

Referenced by df_lr_confluence_0().

static void df_worklist_dataflow_doublequeue	(	struct dataflow *	dataflow,
		bitmap	pending,
		sbitmap	considered,
		int *	blocks_in_postorder,
		unsigned *	bbindex_to_postorder,
		int	n_blocks
	)

static

   Main dataflow solver loop.

   DATAFLOW is problem we are solving, PENDING is worklist of basic blocks we
   need to visit.
   BLOCK_IN_POSTORDER is array of size N_BLOCKS specifying postorder in BBs and
   BBINDEX_TO_POSTORDER is array mapping back BB->index to postorder position.
   PENDING will be freed.

   The worklists are bitmaps indexed by postorder positions.  

   The function implements standard algorithm for dataflow solving with two
   worklists (we are processing WORKLIST and storing new BBs to visit in
   PENDING).

   As an optimization we maintain ages when BB was changed (stored in bb->aux)
   and when it was last visited (stored in last_visit_age).  This avoids need
   to re-do confluence function for edges to basic blocks whose source
   did not change since destination was visited last time.

     Double-queueing. Worklist is for the current iteration,
     and pending is for the next.

         Swap pending and worklist.

     Dump statistics.

static bool df_worklist_propagate_backward	(	struct dataflow *	dataflow,
		unsigned	bb_index,
		unsigned *	bbindex_to_postorder,
		bitmap	pending,
		sbitmap	considered,
		ptrdiff_t	age
	)

static

   Helper function for df_worklist_dataflow.
   Propagate the dataflow backward.

      Calculate <conf_op> of incoming edges.

         The out set of this block has changed.
         Propagate to the outgoing blocks.

static bool df_worklist_propagate_forward	(	struct dataflow *	dataflow,
		unsigned	bb_index,
		unsigned *	bbindex_to_postorder,
		bitmap	pending,
		sbitmap	considered,
		ptrdiff_t	age
	)

static

   Helper function for df_worklist_dataflow.
   Propagate the dataflow forward.
   Given a BB_INDEX, do the dataflow propagation
   and set bits on for successors in PENDING
   if the out set of the dataflow has changed.

   AGE specify time when BB was visited last time.
   AGE of 0 means we are visiting for first time and need to
   compute transfer function to initialize datastructures.
   Otherwise we re-do transfer function only if something change
   while computing confluence functions.
   We need to compute confluence only of basic block that are younger
   then last visit of the BB.

   Return true if BB info has changed.  This is always the case
   in the first visit.

      Calculate <conf_op> of incoming edges.

         The out set of this block has changed.
         Propagate to the outgoing blocks.

void dump_regset ( )

   Write information about registers and basic blocks into FILE.
   This is part of making a debugging dump.

static bool gate_no_opt ( )

static

static bool gate_opt ( )

static

rtl_opt_pass* make_pass_df_finish ( )

References bitmap_bit_p(), changed, df_problem::con_fun_0, df_problem::con_fun_n, edge_def::dest, basic_block_def::index, basic_block_def::preds, dataflow::problem, edge_def::src, basic_block_def::succs, and df_problem::trans_fun.

rtl_opt_pass* make_pass_df_initialize_no_opt ( )

rtl_opt_pass* make_pass_df_initialize_opt ( )

static unsigned int rest_of_handle_df_finish ( )

static

   Free all the dataflow info and the DF structure.  This should be
   called from the df_finish macro which also NULLs the parm.

static unsigned int rest_of_handle_df_initialize ( )

static

   Set up the dataflow instance for the entire back end.

     Set this to a conservative value.  Stack_ptr_mod will compute it
     correctly later.

     These three problems are permanent.

     After reload, some ports add certain bits to regs_ever_live so
     this cannot be reset.

Variable Documentation

struct df_d* df

   This is used for debugging and for the dumpers to find the latest
   instance so that the df info can be added to the dumps.  This
   should not be used by regular code.

Referenced by best_gain_for_invariant(), df_chain_finalize(), df_chain_remove_problem(), df_free_ref(), df_get_eh_block_artificial_uses(), df_grow_insn_info(), df_insn_rescan_debug_internal(), df_lr_confluence_0(), df_lr_init(), df_mw_compare(), df_record_entry_block_defs(), df_ref_chain_delete(), df_ref_change_reg_with_loc_1(), df_reorganize_refs_by_insn_bb(), df_scan_add_problem(), df_scan_free(), print_pred_bbs(), split_live_ranges_for_shrink_wrap(), and unlink_block().

bitmap_obstack df_bitmap_obstack

   An obstack for bitmap not related to specific dataflow problems.
   This obstack should e.g. be used for bitmaps with a short life time
   such as temporary bitmaps.

Referenced by df_get_eh_block_artificial_uses(), df_insn_rescan_debug_internal(), and df_lr_verify_solution_end().

struct bitmap_obstack reg_obstack

   The obstack on which regsets are allocated.

Referenced by get_stored_val(), and remove_pseudos().

int* saved_cfg = NULL

static

Referenced by df_bb_delete(), and df_verify().

struct dataflow user_dflow

static

struct df_problem user_problem

static

Functions

Variables

Function Documentation

Variable Documentation