X-Git-Url: https://oss.titaniummirror.com/gitweb?a=blobdiff_plain;f=gcc%2Fdf-core.c;fp=gcc%2Fdf-core.c;h=7b83dce53f6a04f94f747800b705e74f3b10fb75;hb=6fed43773c9b0ce596dca5686f37ac3fc0fa11c0;hp=0000000000000000000000000000000000000000;hpb=27b11d56b743098deb193d510b337ba22dc52e5c;p=msp430-gcc.git
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+/* Allocation for dataflow support routines.
+ Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
+ 2008 Free Software Foundation, Inc.
+ Originally contributed by Michael P. Hayes
+ (m.hayes@elec.canterbury.ac.nz, mhayes@redhat.com)
+ Major rewrite contributed by Danny Berlin (dberlin@dberlin.org)
+ and Kenneth Zadeck (zadeck@naturalbridge.com).
+
+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
+. */
+
+/*
+OVERVIEW:
+
+The files in this collection (df*.c,df.h) provide a general framework
+for solving dataflow problems. The global dataflow is performed using
+a good implementation of iterative dataflow analysis.
+
+The file df-problems.c provides problem instance for the most common
+dataflow problems: reaching defs, upward exposed uses, live variables,
+uninitialized variables, def-use chains, and use-def chains. However,
+the interface allows other dataflow problems to be defined as well.
+
+Dataflow analysis is available in most of the rtl backend (the parts
+between pass_df_initialize and pass_df_finish). It is quite likely
+that these boundaries will be expanded in the future. The only
+requirement is that there be a correct control flow graph.
+
+There are three variations of the live variable problem that are
+available whenever dataflow is available. The LR problem finds the
+areas that can reach a use of a variable, the UR problems finds the
+areas that can be reached from a definition of a variable. The LIVE
+problem finds the intersection of these two areas.
+
+There are several optional problems. These can be enabled when they
+are needed and disabled when they are not needed.
+
+Dataflow problems are generally solved in three layers. The bottom
+layer is called scanning where a data structure is built for each rtl
+insn that describes the set of defs and uses of that insn. Scanning
+is generally kept up to date, i.e. as the insns changes, the scanned
+version of that insn changes also. There are various mechanisms for
+making this happen and are described in the INCREMENTAL SCANNING
+section.
+
+In the middle layer, basic blocks are scanned to produce transfer
+functions which describe the effects of that block on the global
+dataflow solution. The transfer functions are only rebuilt if the
+some instruction within the block has changed.
+
+The top layer is the dataflow solution itself. The dataflow solution
+is computed by using an efficient iterative solver and the transfer
+functions. The dataflow solution must be recomputed whenever the
+control changes or if one of the transfer function changes.
+
+
+USAGE:
+
+Here is an example of using the dataflow routines.
+
+ df_[chain,live,note,rd]_add_problem (flags);
+
+ df_set_blocks (blocks);
+
+ df_analyze ();
+
+ df_dump (stderr);
+
+ df_finish_pass (false);
+
+DF_[chain,live,note,rd]_ADD_PROBLEM adds a problem, defined by an
+instance to struct df_problem, to the set of problems solved in this
+instance of df. All calls to add a problem for a given instance of df
+must occur before the first call to DF_ANALYZE.
+
+Problems can be dependent on other problems. For instance, solving
+def-use or use-def chains is dependent on solving reaching
+definitions. As long as these dependencies are listed in the problem
+definition, the order of adding the problems is not material.
+Otherwise, the problems will be solved in the order of calls to
+df_add_problem. Note that it is not necessary to have a problem. In
+that case, df will just be used to do the scanning.
+
+
+
+DF_SET_BLOCKS is an optional call used to define a region of the
+function on which the analysis will be performed. The normal case is
+to analyze the entire function and no call to df_set_blocks is made.
+DF_SET_BLOCKS only effects the blocks that are effected when computing
+the transfer functions and final solution. The insn level information
+is always kept up to date.
+
+When a subset is given, the analysis behaves as if the function only
+contains those blocks and any edges that occur directly between the
+blocks in the set. Care should be taken to call df_set_blocks right
+before the call to analyze in order to eliminate the possibility that
+optimizations that reorder blocks invalidate the bitvector.
+
+DF_ANALYZE causes all of the defined problems to be (re)solved. When
+DF_ANALYZE is completes, the IN and OUT sets for each basic block
+contain the computer information. The DF_*_BB_INFO macros can be used
+to access these bitvectors. All deferred rescannings are down before
+the transfer functions are recomputed.
+
+DF_DUMP can then be called to dump the information produce to some
+file. This calls DF_DUMP_START, to print the information that is not
+basic block specific, and then calls DF_DUMP_TOP and DF_DUMP_BOTTOM
+for each block to print the basic specific information. These parts
+can all be called separately as part of a larger dump function.
+
+
+DF_FINISH_PASS causes df_remove_problem to be called on all of the
+optional problems. It also causes any insns whose scanning has been
+deferred to be rescanned as well as clears all of the changeable flags.
+Setting the pass manager TODO_df_finish flag causes this function to
+be run. However, the pass manager will call df_finish_pass AFTER the
+pass dumping has been done, so if you want to see the results of the
+optional problems in the pass dumps, use the TODO flag rather than
+calling the function yourself.
+
+INCREMENTAL SCANNING
+
+There are four ways of doing the incremental scanning:
+
+1) Immediate rescanning - Calls to df_insn_rescan, df_notes_rescan,
+ df_bb_delete, df_insn_change_bb have been added to most of
+ the low level service functions that maintain the cfg and change
+ rtl. Calling and of these routines many cause some number of insns
+ to be rescanned.
+
+ For most modern rtl passes, this is certainly the easiest way to
+ manage rescanning the insns. This technique also has the advantage
+ that the scanning information is always correct and can be relied
+ upon even after changes have been made to the instructions. This
+ technique is contra indicated in several cases:
+
+ a) If def-use chains OR use-def chains (but not both) are built,
+ using this is SIMPLY WRONG. The problem is that when a ref is
+ deleted that is the target of an edge, there is not enough
+ information to efficiently find the source of the edge and
+ delete the edge. This leaves a dangling reference that may
+ cause problems.
+
+ b) If def-use chains AND use-def chains are built, this may
+ produce unexpected results. The problem is that the incremental
+ scanning of an insn does not know how to repair the chains that
+ point into an insn when the insn changes. So the incremental
+ scanning just deletes the chains that enter and exit the insn
+ being changed. The dangling reference issue in (a) is not a
+ problem here, but if the pass is depending on the chains being
+ maintained after insns have been modified, this technique will
+ not do the correct thing.
+
+ c) If the pass modifies insns several times, this incremental
+ updating may be expensive.
+
+ d) If the pass modifies all of the insns, as does register
+ allocation, it is simply better to rescan the entire function.
+
+ e) If the pass uses either non-standard or ancient techniques to
+ modify insns, automatic detection of the insns that need to be
+ rescanned may be impractical. Cse and regrename fall into this
+ category.
+
+2) Deferred rescanning - Calls to df_insn_rescan, df_notes_rescan, and
+ df_insn_delete do not immediately change the insn but instead make
+ a note that the insn needs to be rescanned. The next call to
+ df_analyze, df_finish_pass, or df_process_deferred_rescans will
+ cause all of the pending rescans to be processed.
+
+ This is the technique of choice if either 1a, 1b, or 1c are issues
+ in the pass. In the case of 1a or 1b, a call to df_remove_problem
+ (df_chain) should be made before the next call to df_analyze or
+ df_process_deferred_rescans.
+
+ To enable this mode, call df_set_flags (DF_DEFER_INSN_RESCAN).
+ (This mode can be cleared by calling df_clear_flags
+ (DF_DEFER_INSN_RESCAN) but this does not cause the deferred insns to
+ be rescanned.
+
+ 3) Total rescanning - In this mode the rescanning is disabled.
+ However, the df information associated with deleted insn is delete
+ at the time the insn is deleted. At the end of the pass, a call
+ must be made to df_insn_rescan_all. This method is used by the
+ register allocator since it generally changes each insn multiple
+ times (once for each ref) and does not need to make use of the
+ updated scanning information.
+
+ It is also currently used by two older passes (cse, and regrename)
+ which change insns in hard to track ways. It is hoped that this
+ will be fixed soon since this it is expensive to rescan all of the
+ insns when only a small number of them have really changed.
+
+4) Do it yourself - In this mechanism, the pass updates the insns
+ itself using the low level df primitives. Currently no pass does
+ this, but it has the advantage that it is quite efficient given
+ that the pass generally has exact knowledge of what it is changing.
+
+DATA STRUCTURES
+
+Scanning produces a `struct df_ref' data structure (ref) is allocated
+for every register reference (def or use) and this records the insn
+and bb the ref is found within. The refs are linked together in
+chains of uses and defs for each insn and for each register. Each ref
+also has a chain field that links all the use refs for a def or all
+the def refs for a use. This is used to create use-def or def-use
+chains.
+
+Different optimizations have different needs. Ultimately, only
+register allocation and schedulers should be using the bitmaps
+produced for the live register and uninitialized register problems.
+The rest of the backend should be upgraded to using and maintaining
+the linked information such as def use or use def chains.
+
+
+PHILOSOPHY:
+
+While incremental bitmaps are not worthwhile to maintain, incremental
+chains may be perfectly reasonable. The fastest way to build chains
+from scratch or after significant modifications is to build reaching
+definitions (RD) and build the chains from this.
+
+However, general algorithms for maintaining use-def or def-use chains
+are not practical. The amount of work to recompute the chain any
+chain after an arbitrary change is large. However, with a modest
+amount of work it is generally possible to have the application that
+uses the chains keep them up to date. The high level knowledge of
+what is really happening is essential to crafting efficient
+incremental algorithms.
+
+As for the bit vector problems, there is no interface to give a set of
+blocks over with to resolve the iteration. In general, restarting a
+dataflow iteration is difficult and expensive. Again, the best way to
+keep the dataflow information up to data (if this is really what is
+needed) it to formulate a problem specific solution.
+
+There are fine grained calls for creating and deleting references from
+instructions in df-scan.c. However, these are not currently connected
+to the engine that resolves the dataflow equations.
+
+
+DATA STRUCTURES:
+
+The basic object is a DF_REF (reference) and this may either be a
+DEF (definition) or a USE of a register.
+
+These are linked into a variety of lists; namely reg-def, reg-use,
+insn-def, insn-use, def-use, and use-def lists. For example, the
+reg-def lists contain all the locations that define a given register
+while the insn-use lists contain all the locations that use a
+register.
+
+Note that the reg-def and reg-use chains are generally short for
+pseudos and long for the hard registers.
+
+ACCESSING INSNS:
+
+1) The df insn information is kept in an array of DF_INSN_INFO objects.
+ The array is indexed by insn uid, and every DF_REF points to the
+ DF_INSN_INFO object of the insn that contains the reference.
+
+2) Each insn has three sets of refs, which are linked into one of three
+ lists: The insn's defs list (accessed by the DF_INSN_INFO_DEFS,
+ DF_INSN_DEFS, or DF_INSN_UID_DEFS macros), the insn's uses list
+ (accessed by the DF_INSN_INFO_USES, DF_INSN_USES, or
+ DF_INSN_UID_USES macros) or the insn's eq_uses list (accessed by the
+ DF_INSN_INFO_EQ_USES, DF_INSN_EQ_USES or DF_INSN_UID_EQ_USES macros).
+ The latter list are the list of references in REG_EQUAL or REG_EQUIV
+ notes. These macros produce a ref (or NULL), the rest of the list
+ can be obtained by traversal of the NEXT_REF field (accessed by the
+ DF_REF_NEXT_REF macro.) There is no significance to the ordering of
+ the uses or refs in an instruction.
+
+3) Each insn has a logical uid field (LUID) which is stored in the
+ DF_INSN_INFO object for the insn. The LUID field is accessed by
+ the DF_INSN_INFO_LUID, DF_INSN_LUID, and DF_INSN_UID_LUID macros.
+ When properly set, the LUID is an integer that numbers each insn in
+ the basic block, in order from the start of the block.
+ The numbers are only correct after a call to df_analyze. They will
+ rot after insns are added deleted or moved round.
+
+ACCESSING REFS:
+
+There are 4 ways to obtain access to refs:
+
+1) References are divided into two categories, REAL and ARTIFICIAL.
+
+ REAL refs are associated with instructions.
+
+ ARTIFICIAL refs are associated with basic blocks. The heads of
+ these lists can be accessed by calling df_get_artificial_defs or
+ df_get_artificial_uses for the particular basic block.
+
+ Artificial defs and uses occur both at the beginning and ends of blocks.
+
+ For blocks that area at the destination of eh edges, the
+ artificial uses and defs occur at the beginning. The defs relate
+ to the registers specified in EH_RETURN_DATA_REGNO and the uses
+ relate to the registers specified in ED_USES. Logically these
+ defs and uses should really occur along the eh edge, but there is
+ no convenient way to do this. Artificial edges that occur at the
+ beginning of the block have the DF_REF_AT_TOP flag set.
+
+ Artificial uses occur at the end of all blocks. These arise from
+ the hard registers that are always live, such as the stack
+ register and are put there to keep the code from forgetting about
+ them.
+
+ Artificial defs occur at the end of the entry block. These arise
+ from registers that are live at entry to the function.
+
+2) There are three types of refs: defs, uses and eq_uses. (Eq_uses are
+ uses that appear inside a REG_EQUAL or REG_EQUIV note.)
+
+ All of the eq_uses, uses and defs associated with each pseudo or
+ hard register may be linked in a bidirectional chain. These are
+ called reg-use or reg_def chains. If the changeable flag
+ DF_EQ_NOTES is set when the chains are built, the eq_uses will be
+ treated like uses. If it is not set they are ignored.
+
+ The first use, eq_use or def for a register can be obtained using
+ the DF_REG_USE_CHAIN, DF_REG_EQ_USE_CHAIN or DF_REG_DEF_CHAIN
+ macros. Subsequent uses for the same regno can be obtained by
+ following the next_reg field of the ref. The number of elements in
+ each of the chains can be found by using the DF_REG_USE_COUNT,
+ DF_REG_EQ_USE_COUNT or DF_REG_DEF_COUNT macros.
+
+ In previous versions of this code, these chains were ordered. It
+ has not been practical to continue this practice.
+
+3) If def-use or use-def chains are built, these can be traversed to
+ get to other refs. If the flag DF_EQ_NOTES has been set, the chains
+ include the eq_uses. Otherwise these are ignored when building the
+ chains.
+
+4) An array of all of the uses (and an array of all of the defs) can
+ be built. These arrays are indexed by the value in the id
+ structure. These arrays are only lazily kept up to date, and that
+ process can be expensive. To have these arrays built, call
+ df_reorganize_defs or df_reorganize_uses. If the flag DF_EQ_NOTES
+ has been set the array will contain the eq_uses. Otherwise these
+ are ignored when building the array and assigning the ids. Note
+ that the values in the id field of a ref may change across calls to
+ df_analyze or df_reorganize_defs or df_reorganize_uses.
+
+ If the only use of this array is to find all of the refs, it is
+ better to traverse all of the registers and then traverse all of
+ reg-use or reg-def chains.
+
+NOTES:
+
+Embedded addressing side-effects, such as POST_INC or PRE_INC, generate
+both a use and a def. These are both marked read/write to show that they
+are dependent. For example, (set (reg 40) (mem (post_inc (reg 42))))
+will generate a use of reg 42 followed by a def of reg 42 (both marked
+read/write). Similarly, (set (reg 40) (mem (pre_dec (reg 41))))
+generates a use of reg 41 then a def of reg 41 (both marked read/write),
+even though reg 41 is decremented before it is used for the memory
+address in this second example.
+
+A set to a REG inside a ZERO_EXTRACT, or a set to a non-paradoxical SUBREG
+for which the number of word_mode units covered by the outer mode is
+smaller than that covered by the inner mode, invokes a read-modify-write
+operation. We generate both a use and a def and again mark them
+read/write.
+
+Paradoxical subreg writes do not leave a trace of the old content, so they
+are write-only operations.
+*/
+
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
+#include "rtl.h"
+#include "tm_p.h"
+#include "insn-config.h"
+#include "recog.h"
+#include "function.h"
+#include "regs.h"
+#include "output.h"
+#include "alloc-pool.h"
+#include "flags.h"
+#include "hard-reg-set.h"
+#include "basic-block.h"
+#include "sbitmap.h"
+#include "bitmap.h"
+#include "timevar.h"
+#include "df.h"
+#include "tree-pass.h"
+#include "params.h"
+
+static void *df_get_bb_info (struct dataflow *, unsigned int);
+static void df_set_bb_info (struct dataflow *, unsigned int, void *);
+#ifdef DF_DEBUG_CFG
+static void df_set_clean_cfg (void);
+#endif
+
+/* 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. */
+
+bitmap_obstack df_bitmap_obstack;
+
+
+/*----------------------------------------------------------------------------
+ Functions to create, destroy and manipulate an instance of df.
+----------------------------------------------------------------------------*/
+
+struct df *df;
+
+/* Add PROBLEM (and any dependent problems) to the DF instance. */
+
+void
+df_add_problem (struct df_problem *problem)
+{
+ struct dataflow *dflow;
+ int i;
+
+ /* First try to add the dependent problem. */
+ if (problem->dependent_problem)
+ df_add_problem (problem->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. */
+ dflow = df->problems_by_index[problem->id];
+ if (dflow)
+ return;
+
+ /* Make a new one and add it to the end. */
+ dflow = XCNEW (struct dataflow);
+ dflow->problem = problem;
+ dflow->computed = false;
+ dflow->solutions_dirty = true;
+ df->problems_by_index[dflow->problem->id] = dflow;
+
+ /* 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. */
+ df->num_problems_defined++;
+ for (i = df->num_problems_defined - 2; i >= 0; i--)
+ {
+ if (problem->id < df->problems_in_order[i]->problem->id)
+ df->problems_in_order[i+1] = df->problems_in_order[i];
+ else
+ {
+ df->problems_in_order[i+1] = dflow;
+ return;
+ }
+ }
+ df->problems_in_order[0] = dflow;
+}
+
+
+/* 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. */
+enum df_changeable_flags
+df_set_flags (enum df_changeable_flags changeable_flags)
+{
+ enum df_changeable_flags old_flags = df->changeable_flags;
+ df->changeable_flags |= changeable_flags;
+ return old_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. */
+enum df_changeable_flags
+df_clear_flags (enum df_changeable_flags changeable_flags)
+{
+ enum df_changeable_flags old_flags = df->changeable_flags;
+ df->changeable_flags &= ~changeable_flags;
+ return old_flags;
+}
+
+
+/* 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. */
+
+void
+df_set_blocks (bitmap blocks)
+{
+ if (blocks)
+ {
+ if (dump_file)
+ bitmap_print (dump_file, blocks, "setting blocks to analyze ", "\n");
+ if (df->blocks_to_analyze)
+ {
+ /* This block is called to change the focus from one subset
+ to another. */
+ int p;
+ bitmap diff = BITMAP_ALLOC (&df_bitmap_obstack);
+ bitmap_and_compl (diff, df->blocks_to_analyze, blocks);
+ for (p = 0; p < df->num_problems_defined; p++)
+ {
+ struct dataflow *dflow = df->problems_in_order[p];
+ if (dflow->optional_p && dflow->problem->reset_fun)
+ dflow->problem->reset_fun (df->blocks_to_analyze);
+ else if (dflow->problem->free_blocks_on_set_blocks)
+ {
+ bitmap_iterator bi;
+ unsigned int bb_index;
+
+ EXECUTE_IF_SET_IN_BITMAP (diff, 0, bb_index, bi)
+ {
+ basic_block bb = BASIC_BLOCK (bb_index);
+ if (bb)
+ {
+ void *bb_info = df_get_bb_info (dflow, bb_index);
+ if (bb_info)
+ {
+ dflow->problem->free_bb_fun (bb, bb_info);
+ df_set_bb_info (dflow, bb_index, NULL);
+ }
+ }
+ }
+ }
+ }
+
+ BITMAP_FREE (diff);
+ }
+ else
+ {
+ /* This block of code is executed to change the focus from
+ the entire function to a subset. */
+ bitmap blocks_to_reset = NULL;
+ int p;
+ for (p = 0; p < df->num_problems_defined; p++)
+ {
+ struct dataflow *dflow = df->problems_in_order[p];
+ if (dflow->optional_p && dflow->problem->reset_fun)
+ {
+ if (!blocks_to_reset)
+ {
+ basic_block bb;
+ blocks_to_reset =
+ BITMAP_ALLOC (&df_bitmap_obstack);
+ FOR_ALL_BB(bb)
+ {
+ bitmap_set_bit (blocks_to_reset, bb->index);
+ }
+ }
+ dflow->problem->reset_fun (blocks_to_reset);
+ }
+ }
+ if (blocks_to_reset)
+ BITMAP_FREE (blocks_to_reset);
+
+ df->blocks_to_analyze = BITMAP_ALLOC (&df_bitmap_obstack);
+ }
+ bitmap_copy (df->blocks_to_analyze, blocks);
+ df->analyze_subset = true;
+ }
+ else
+ {
+ /* This block is executed to reset the focus to the entire
+ function. */
+ if (dump_file)
+ fprintf (dump_file, "clearing blocks_to_analyze\n");
+ if (df->blocks_to_analyze)
+ {
+ BITMAP_FREE (df->blocks_to_analyze);
+ df->blocks_to_analyze = NULL;
+ }
+ df->analyze_subset = false;
+ }
+
+ /* Setting the blocks causes the refs to be unorganized since only
+ the refs in the blocks are seen. */
+ df_maybe_reorganize_def_refs (DF_REF_ORDER_NO_TABLE);
+ df_maybe_reorganize_use_refs (DF_REF_ORDER_NO_TABLE);
+ df_mark_solutions_dirty ();
+}
+
+
+/* Delete a DFLOW problem (and any problems that depend on this
+ problem). */
+
+void
+df_remove_problem (struct dataflow *dflow)
+{
+ struct df_problem *problem;
+ int i;
+
+ if (!dflow)
+ return;
+
+ problem = dflow->problem;
+ gcc_assert (problem->remove_problem_fun);
+
+ /* Delete any problems that depended on this problem first. */
+ for (i = 0; i < df->num_problems_defined; i++)
+ if (df->problems_in_order[i]->problem->dependent_problem == problem)
+ df_remove_problem (df->problems_in_order[i]);
+
+ /* Now remove this problem. */
+ for (i = 0; i < df->num_problems_defined; i++)
+ if (df->problems_in_order[i] == dflow)
+ {
+ int j;
+ for (j = i + 1; j < df->num_problems_defined; j++)
+ df->problems_in_order[j-1] = df->problems_in_order[j];
+ df->problems_in_order[j-1] = NULL;
+ df->num_problems_defined--;
+ break;
+ }
+
+ (problem->remove_problem_fun) ();
+ df->problems_by_index[problem->id] = NULL;
+}
+
+
+/* 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. */
+
+void
+df_finish_pass (bool verify ATTRIBUTE_UNUSED)
+{
+ int i;
+ int removed = 0;
+
+#ifdef ENABLE_DF_CHECKING
+ enum df_changeable_flags saved_flags;
+#endif
+
+ if (!df)
+ return;
+
+ df_maybe_reorganize_def_refs (DF_REF_ORDER_NO_TABLE);
+ df_maybe_reorganize_use_refs (DF_REF_ORDER_NO_TABLE);
+
+#ifdef ENABLE_DF_CHECKING
+ saved_flags = df->changeable_flags;
+#endif
+
+ for (i = 0; i < df->num_problems_defined; i++)
+ {
+ struct dataflow *dflow = df->problems_in_order[i];
+ struct df_problem *problem = dflow->problem;
+
+ if (dflow->optional_p)
+ {
+ gcc_assert (problem->remove_problem_fun);
+ (problem->remove_problem_fun) ();
+ df->problems_in_order[i] = NULL;
+ df->problems_by_index[problem->id] = NULL;
+ removed++;
+ }
+ }
+ df->num_problems_defined -= removed;
+
+ /* Clear all of the flags. */
+ df->changeable_flags = 0;
+ df_process_deferred_rescans ();
+
+ /* Set the focus back to the whole function. */
+ if (df->blocks_to_analyze)
+ {
+ BITMAP_FREE (df->blocks_to_analyze);
+ df->blocks_to_analyze = NULL;
+ df_mark_solutions_dirty ();
+ df->analyze_subset = false;
+ }
+
+#ifdef ENABLE_DF_CHECKING
+ /* Verification will fail in DF_NO_INSN_RESCAN. */
+ if (!(saved_flags & DF_NO_INSN_RESCAN))
+ {
+ df_lr_verify_transfer_functions ();
+ if (df_live)
+ df_live_verify_transfer_functions ();
+ }
+
+#ifdef DF_DEBUG_CFG
+ df_set_clean_cfg ();
+#endif
+#endif
+
+#ifdef ENABLE_CHECKING
+ if (verify)
+ df->changeable_flags |= DF_VERIFY_SCHEDULED;
+#endif
+}
+
+
+/* Set up the dataflow instance for the entire back end. */
+
+static unsigned int
+rest_of_handle_df_initialize (void)
+{
+ gcc_assert (!df);
+ df = XCNEW (struct df);
+ df->changeable_flags = 0;
+
+ bitmap_obstack_initialize (&df_bitmap_obstack);
+
+ /* Set this to a conservative value. Stack_ptr_mod will compute it
+ correctly later. */
+ current_function_sp_is_unchanging = 0;
+
+ df_scan_add_problem ();
+ df_scan_alloc (NULL);
+
+ /* These three problems are permanent. */
+ df_lr_add_problem ();
+ if (optimize > 1)
+ df_live_add_problem ();
+
+ df->postorder = XNEWVEC (int, last_basic_block);
+ df->postorder_inverted = XNEWVEC (int, last_basic_block);
+ df->n_blocks = post_order_compute (df->postorder, true, true);
+ df->n_blocks_inverted = inverted_post_order_compute (df->postorder_inverted);
+ gcc_assert (df->n_blocks == df->n_blocks_inverted);
+
+ df->hard_regs_live_count = XNEWVEC (unsigned int, FIRST_PSEUDO_REGISTER);
+ memset (df->hard_regs_live_count, 0,
+ sizeof (unsigned int) * FIRST_PSEUDO_REGISTER);
+
+ df_hard_reg_init ();
+ /* After reload, some ports add certain bits to regs_ever_live so
+ this cannot be reset. */
+ df_compute_regs_ever_live (true);
+ df_scan_blocks ();
+ df_compute_regs_ever_live (false);
+ return 0;
+}
+
+
+static bool
+gate_opt (void)
+{
+ return optimize > 0;
+}
+
+
+struct rtl_opt_pass pass_df_initialize_opt =
+{
+ {
+ RTL_PASS,
+ "dfinit", /* name */
+ gate_opt, /* gate */
+ rest_of_handle_df_initialize, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ 0, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0 /* todo_flags_finish */
+ }
+};
+
+
+static bool
+gate_no_opt (void)
+{
+ return optimize == 0;
+}
+
+
+struct rtl_opt_pass pass_df_initialize_no_opt =
+{
+ {
+ RTL_PASS,
+ "dfinit", /* name */
+ gate_no_opt, /* gate */
+ rest_of_handle_df_initialize, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ 0, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0 /* todo_flags_finish */
+ }
+};
+
+
+/* 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_finish (void)
+{
+ int i;
+
+ gcc_assert (df);
+
+ for (i = 0; i < df->num_problems_defined; i++)
+ {
+ struct dataflow *dflow = df->problems_in_order[i];
+ dflow->problem->free_fun ();
+ }
+
+ if (df->postorder)
+ free (df->postorder);
+ if (df->postorder_inverted)
+ free (df->postorder_inverted);
+ free (df->hard_regs_live_count);
+ free (df);
+ df = NULL;
+
+ bitmap_obstack_release (&df_bitmap_obstack);
+ return 0;
+}
+
+
+struct rtl_opt_pass pass_df_finish =
+{
+ {
+ RTL_PASS,
+ "dfinish", /* name */
+ NULL, /* gate */
+ rest_of_handle_df_finish, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ 0, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0 /* todo_flags_finish */
+ }
+};
+
+
+
+
+
+/*----------------------------------------------------------------------------
+ The general data flow analysis engine.
+----------------------------------------------------------------------------*/
+
+
+/* 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. */
+
+static void
+df_worklist_propagate_forward (struct dataflow *dataflow,
+ unsigned bb_index,
+ unsigned *bbindex_to_postorder,
+ bitmap pending,
+ sbitmap considered)
+{
+ edge e;
+ edge_iterator ei;
+ basic_block bb = BASIC_BLOCK (bb_index);
+
+ /* Calculate of incoming edges. */
+ if (EDGE_COUNT (bb->preds) > 0)
+ FOR_EACH_EDGE (e, ei, bb->preds)
+ {
+ if (TEST_BIT (considered, e->src->index))
+ dataflow->problem->con_fun_n (e);
+ }
+ else if (dataflow->problem->con_fun_0)
+ dataflow->problem->con_fun_0 (bb);
+
+ if (dataflow->problem->trans_fun (bb_index))
+ {
+ /* The out set of this block has changed.
+ Propagate to the outgoing blocks. */
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ {
+ unsigned ob_index = e->dest->index;
+
+ if (TEST_BIT (considered, ob_index))
+ bitmap_set_bit (pending, bbindex_to_postorder[ob_index]);
+ }
+ }
+}
+
+
+/* Helper function for df_worklist_dataflow.
+ Propagate the dataflow backward. */
+
+static void
+df_worklist_propagate_backward (struct dataflow *dataflow,
+ unsigned bb_index,
+ unsigned *bbindex_to_postorder,
+ bitmap pending,
+ sbitmap considered)
+{
+ edge e;
+ edge_iterator ei;
+ basic_block bb = BASIC_BLOCK (bb_index);
+
+ /* Calculate of incoming edges. */
+ if (EDGE_COUNT (bb->succs) > 0)
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ {
+ if (TEST_BIT (considered, e->dest->index))
+ dataflow->problem->con_fun_n (e);
+ }
+ else if (dataflow->problem->con_fun_0)
+ dataflow->problem->con_fun_0 (bb);
+
+ if (dataflow->problem->trans_fun (bb_index))
+ {
+ /* The out set of this block has changed.
+ Propagate to the outgoing blocks. */
+ FOR_EACH_EDGE (e, ei, bb->preds)
+ {
+ unsigned ob_index = e->src->index;
+
+ if (TEST_BIT (considered, ob_index))
+ bitmap_set_bit (pending, bbindex_to_postorder[ob_index]);
+ }
+ }
+}
+
+
+
+/* This will free "pending". */
+
+static void
+df_worklist_dataflow_doublequeue (struct dataflow *dataflow,
+ bitmap pending,
+ sbitmap considered,
+ int *blocks_in_postorder,
+ unsigned *bbindex_to_postorder)
+{
+ enum df_flow_dir dir = dataflow->problem->dir;
+ int dcount = 0;
+ bitmap worklist = BITMAP_ALLOC (&df_bitmap_obstack);
+
+ /* Double-queueing. Worklist is for the current iteration,
+ and pending is for the next. */
+ while (!bitmap_empty_p (pending))
+ {
+ /* Swap pending and worklist. */
+ bitmap temp = worklist;
+ worklist = pending;
+ pending = temp;
+
+ do
+ {
+ int index;
+ unsigned bb_index;
+ dcount++;
+
+ index = bitmap_first_set_bit (worklist);
+ bitmap_clear_bit (worklist, index);
+
+ bb_index = blocks_in_postorder[index];
+
+ if (dir == DF_FORWARD)
+ df_worklist_propagate_forward (dataflow, bb_index,
+ bbindex_to_postorder,
+ pending, considered);
+ else
+ df_worklist_propagate_backward (dataflow, bb_index,
+ bbindex_to_postorder,
+ pending, considered);
+ }
+ while (!bitmap_empty_p (worklist));
+ }
+
+ BITMAP_FREE (worklist);
+ BITMAP_FREE (pending);
+
+ /* Dump statistics. */
+ if (dump_file)
+ fprintf (dump_file, "df_worklist_dataflow_doublequeue:"
+ "n_basic_blocks %d n_edges %d"
+ " count %d (%5.2g)\n",
+ n_basic_blocks, n_edges,
+ dcount, dcount / (float)n_basic_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. */
+
+void
+df_worklist_dataflow (struct dataflow *dataflow,
+ bitmap blocks_to_consider,
+ int *blocks_in_postorder,
+ int n_blocks)
+{
+ bitmap pending = BITMAP_ALLOC (&df_bitmap_obstack);
+ sbitmap considered = sbitmap_alloc (last_basic_block);
+ bitmap_iterator bi;
+ unsigned int *bbindex_to_postorder;
+ int i;
+ unsigned int index;
+ enum df_flow_dir dir = dataflow->problem->dir;
+
+ gcc_assert (dir != DF_NONE);
+
+ /* BBINDEX_TO_POSTORDER maps the bb->index to the reverse postorder. */
+ bbindex_to_postorder =
+ (unsigned int *)xmalloc (last_basic_block * sizeof (unsigned int));
+
+ /* Initialize the array to an out-of-bound value. */
+ for (i = 0; i < last_basic_block; i++)
+ bbindex_to_postorder[i] = last_basic_block;
+
+ /* Initialize the considered map. */
+ sbitmap_zero (considered);
+ EXECUTE_IF_SET_IN_BITMAP (blocks_to_consider, 0, index, bi)
+ {
+ SET_BIT (considered, index);
+ }
+
+ /* Initialize the mapping of block index to postorder. */
+ for (i = 0; i < n_blocks; i++)
+ {
+ bbindex_to_postorder[blocks_in_postorder[i]] = i;
+ /* Add all blocks to the worklist. */
+ bitmap_set_bit (pending, i);
+ }
+
+ /* Initialize the problem. */
+ if (dataflow->problem->init_fun)
+ dataflow->problem->init_fun (blocks_to_consider);
+
+ /* Solve it. */
+ df_worklist_dataflow_doublequeue (dataflow, pending, considered,
+ blocks_in_postorder,
+ bbindex_to_postorder);
+
+ sbitmap_free (considered);
+ free (bbindex_to_postorder);
+}
+
+
+/* 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. */
+
+static unsigned
+df_prune_to_subcfg (int list[], unsigned len, bitmap blocks)
+{
+ unsigned act, last;
+
+ for (act = 0, last = 0; act < len; act++)
+ if (bitmap_bit_p (blocks, list[act]))
+ list[last++] = list[act];
+
+ return last;
+}
+
+
+/* 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.
+*/
+
+void
+df_analyze_problem (struct dataflow *dflow,
+ bitmap blocks_to_consider,
+ int *postorder, int n_blocks)
+{
+ timevar_push (dflow->problem->tv_id);
+
+#ifdef ENABLE_DF_CHECKING
+ if (dflow->problem->verify_start_fun)
+ dflow->problem->verify_start_fun ();
+#endif
+
+ /* (Re)Allocate the datastructures necessary to solve the problem. */
+ if (dflow->problem->alloc_fun)
+ dflow->problem->alloc_fun (blocks_to_consider);
+
+ /* Set up the problem and compute the local information. */
+ if (dflow->problem->local_compute_fun)
+ dflow->problem->local_compute_fun (blocks_to_consider);
+
+ /* Solve the equations. */
+ if (dflow->problem->dataflow_fun)
+ dflow->problem->dataflow_fun (dflow, blocks_to_consider,
+ postorder, n_blocks);
+
+ /* Massage the solution. */
+ if (dflow->problem->finalize_fun)
+ dflow->problem->finalize_fun (blocks_to_consider);
+
+#ifdef ENABLE_DF_CHECKING
+ if (dflow->problem->verify_end_fun)
+ dflow->problem->verify_end_fun ();
+#endif
+
+ timevar_pop (dflow->problem->tv_id);
+
+ dflow->computed = true;
+}
+
+
+/* Analyze dataflow info for the basic blocks specified by the bitmap
+ BLOCKS, or for the whole CFG if BLOCKS is zero. */
+
+void
+df_analyze (void)
+{
+ bitmap current_all_blocks = BITMAP_ALLOC (&df_bitmap_obstack);
+ bool everything;
+ int i;
+
+ if (df->postorder)
+ free (df->postorder);
+ if (df->postorder_inverted)
+ free (df->postorder_inverted);
+ df->postorder = XNEWVEC (int, last_basic_block);
+ df->postorder_inverted = XNEWVEC (int, last_basic_block);
+ df->n_blocks = post_order_compute (df->postorder, true, true);
+ df->n_blocks_inverted = inverted_post_order_compute (df->postorder_inverted);
+
+ /* These should be the same. */
+ gcc_assert (df->n_blocks == df->n_blocks_inverted);
+
+ /* We need to do this before the df_verify_all because this is
+ not kept incrementally up to date. */
+ df_compute_regs_ever_live (false);
+ df_process_deferred_rescans ();
+
+ if (dump_file)
+ fprintf (dump_file, "df_analyze called\n");
+
+#ifndef ENABLE_DF_CHECKING
+ if (df->changeable_flags & DF_VERIFY_SCHEDULED)
+#endif
+ df_verify ();
+
+ for (i = 0; i < df->n_blocks; i++)
+ bitmap_set_bit (current_all_blocks, df->postorder[i]);
+
+#ifdef ENABLE_CHECKING
+ /* Verify that POSTORDER_INVERTED only contains blocks reachable from
+ the ENTRY block. */
+ for (i = 0; i < df->n_blocks_inverted; i++)
+ gcc_assert (bitmap_bit_p (current_all_blocks, df->postorder_inverted[i]));
+#endif
+
+ /* Make sure that we have pruned any unreachable blocks from these
+ sets. */
+ if (df->analyze_subset)
+ {
+ everything = false;
+ bitmap_and_into (df->blocks_to_analyze, current_all_blocks);
+ df->n_blocks = df_prune_to_subcfg (df->postorder,
+ df->n_blocks, df->blocks_to_analyze);
+ df->n_blocks_inverted = df_prune_to_subcfg (df->postorder_inverted,
+ df->n_blocks_inverted,
+ df->blocks_to_analyze);
+ BITMAP_FREE (current_all_blocks);
+ }
+ else
+ {
+ everything = true;
+ df->blocks_to_analyze = current_all_blocks;
+ current_all_blocks = NULL;
+ }
+
+ /* Skip over the DF_SCAN problem. */
+ for (i = 1; i < df->num_problems_defined; i++)
+ {
+ struct dataflow *dflow = df->problems_in_order[i];
+ if (dflow->solutions_dirty)
+ {
+ if (dflow->problem->dir == DF_FORWARD)
+ df_analyze_problem (dflow,
+ df->blocks_to_analyze,
+ df->postorder_inverted,
+ df->n_blocks_inverted);
+ else
+ df_analyze_problem (dflow,
+ df->blocks_to_analyze,
+ df->postorder,
+ df->n_blocks);
+ }
+ }
+
+ if (everything)
+ {
+ BITMAP_FREE (df->blocks_to_analyze);
+ df->blocks_to_analyze = NULL;
+ }
+
+#ifdef DF_DEBUG_CFG
+ df_set_clean_cfg ();
+#endif
+}
+
+
+/* Return the number of basic blocks from the last call to df_analyze. */
+
+int
+df_get_n_blocks (enum df_flow_dir dir)
+{
+ gcc_assert (dir != DF_NONE);
+
+ if (dir == DF_FORWARD)
+ {
+ gcc_assert (df->postorder_inverted);
+ return df->n_blocks_inverted;
+ }
+
+ gcc_assert (df->postorder);
+ return df->n_blocks;
+}
+
+
+/* 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. */
+int *
+df_get_postorder (enum df_flow_dir dir)
+{
+ gcc_assert (dir != DF_NONE);
+
+ if (dir == DF_FORWARD)
+ {
+ gcc_assert (df->postorder_inverted);
+ return df->postorder_inverted;
+ }
+ gcc_assert (df->postorder);
+ return df->postorder;
+}
+
+static struct df_problem user_problem;
+static struct dataflow user_dflow;
+
+/* 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. */
+
+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)
+{
+ memset (&user_problem, 0, sizeof (struct df_problem));
+ user_problem.dir = dir;
+ user_problem.init_fun = init_fun;
+ user_problem.con_fun_0 = con_fun_0;
+ user_problem.con_fun_n = con_fun_n;
+ user_problem.trans_fun = trans_fun;
+ user_dflow.problem = &user_problem;
+ df_worklist_dataflow (&user_dflow, blocks, postorder, n_blocks);
+}
+
+
+
+/*----------------------------------------------------------------------------
+ Functions to support limited incremental change.
+----------------------------------------------------------------------------*/
+
+
+/* Get basic block info. */
+
+static void *
+df_get_bb_info (struct dataflow *dflow, unsigned int index)
+{
+ if (dflow->block_info == NULL)
+ return NULL;
+ if (index >= dflow->block_info_size)
+ return NULL;
+ return (struct df_scan_bb_info *) dflow->block_info[index];
+}
+
+
+/* Set basic block info. */
+
+static void
+df_set_bb_info (struct dataflow *dflow, unsigned int index,
+ void *bb_info)
+{
+ gcc_assert (dflow->block_info);
+ dflow->block_info[index] = bb_info;
+}
+
+
+/* Mark the solutions as being out of date. */
+
+void
+df_mark_solutions_dirty (void)
+{
+ if (df)
+ {
+ int p;
+ for (p = 1; p < df->num_problems_defined; p++)
+ df->problems_in_order[p]->solutions_dirty = true;
+ }
+}
+
+
+/* Return true if BB needs it's transfer functions recomputed. */
+
+bool
+df_get_bb_dirty (basic_block bb)
+{
+ if (df && df_live)
+ return bitmap_bit_p (df_live->out_of_date_transfer_functions, bb->index);
+ else
+ return false;
+}
+
+
+/* Mark BB as needing it's transfer functions as being out of
+ date. */
+
+void
+df_set_bb_dirty (basic_block bb)
+{
+ if (df)
+ {
+ int p;
+ for (p = 1; p < df->num_problems_defined; p++)
+ {
+ struct dataflow *dflow = df->problems_in_order[p];
+ if (dflow->out_of_date_transfer_functions)
+ bitmap_set_bit (dflow->out_of_date_transfer_functions, bb->index);
+ }
+ df_mark_solutions_dirty ();
+ }
+}
+
+
+/* Clear the dirty bits. This is called from places that delete
+ blocks. */
+static void
+df_clear_bb_dirty (basic_block bb)
+{
+ int p;
+ for (p = 1; p < df->num_problems_defined; p++)
+ {
+ struct dataflow *dflow = df->problems_in_order[p];
+ if (dflow->out_of_date_transfer_functions)
+ bitmap_clear_bit (dflow->out_of_date_transfer_functions, bb->index);
+ }
+}
+/* Called from the rtl_compact_blocks to reorganize the problems basic
+ block info. */
+
+void
+df_compact_blocks (void)
+{
+ int i, p;
+ basic_block bb;
+ void **problem_temps;
+ int size = last_basic_block * sizeof (void *);
+ bitmap tmp = BITMAP_ALLOC (&df_bitmap_obstack);
+ problem_temps = XNEWVAR (void *, size);
+
+ for (p = 0; p < df->num_problems_defined; p++)
+ {
+ struct dataflow *dflow = df->problems_in_order[p];
+
+ /* Need to reorganize the out_of_date_transfer_functions for the
+ dflow problem. */
+ if (dflow->out_of_date_transfer_functions)
+ {
+ bitmap_copy (tmp, dflow->out_of_date_transfer_functions);
+ bitmap_clear (dflow->out_of_date_transfer_functions);
+ if (bitmap_bit_p (tmp, ENTRY_BLOCK))
+ bitmap_set_bit (dflow->out_of_date_transfer_functions, ENTRY_BLOCK);
+ if (bitmap_bit_p (tmp, EXIT_BLOCK))
+ bitmap_set_bit (dflow->out_of_date_transfer_functions, EXIT_BLOCK);
+
+ i = NUM_FIXED_BLOCKS;
+ FOR_EACH_BB (bb)
+ {
+ if (bitmap_bit_p (tmp, bb->index))
+ bitmap_set_bit (dflow->out_of_date_transfer_functions, i);
+ i++;
+ }
+ }
+
+ /* Now shuffle the block info for the problem. */
+ if (dflow->problem->free_bb_fun)
+ {
+ df_grow_bb_info (dflow);
+ memcpy (problem_temps, dflow->block_info, size);
+
+ /* 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. */
+ i = NUM_FIXED_BLOCKS;
+ FOR_EACH_BB (bb)
+ {
+ df_set_bb_info (dflow, i, problem_temps[bb->index]);
+ problem_temps[bb->index] = NULL;
+ i++;
+ }
+ memset (dflow->block_info + i, 0,
+ (last_basic_block - i) *sizeof (void *));
+
+ /* Free any block infos that were not copied (and NULLed).
+ These are from orphaned blocks. */
+ for (i = NUM_FIXED_BLOCKS; i < last_basic_block; i++)
+ {
+ basic_block bb = BASIC_BLOCK (i);
+ if (problem_temps[i] && bb)
+ dflow->problem->free_bb_fun
+ (bb, problem_temps[i]);
+ }
+ }
+ }
+
+ /* Shuffle the bits in the basic_block indexed arrays. */
+
+ if (df->blocks_to_analyze)
+ {
+ if (bitmap_bit_p (tmp, ENTRY_BLOCK))
+ bitmap_set_bit (df->blocks_to_analyze, ENTRY_BLOCK);
+ if (bitmap_bit_p (tmp, EXIT_BLOCK))
+ bitmap_set_bit (df->blocks_to_analyze, EXIT_BLOCK);
+ bitmap_copy (tmp, df->blocks_to_analyze);
+ bitmap_clear (df->blocks_to_analyze);
+ i = NUM_FIXED_BLOCKS;
+ FOR_EACH_BB (bb)
+ {
+ if (bitmap_bit_p (tmp, bb->index))
+ bitmap_set_bit (df->blocks_to_analyze, i);
+ i++;
+ }
+ }
+
+ BITMAP_FREE (tmp);
+
+ free (problem_temps);
+
+ i = NUM_FIXED_BLOCKS;
+ FOR_EACH_BB (bb)
+ {
+ SET_BASIC_BLOCK (i, bb);
+ bb->index = i;
+ i++;
+ }
+
+ gcc_assert (i == n_basic_blocks);
+
+ for (; i < last_basic_block; i++)
+ SET_BASIC_BLOCK (i, NULL);
+
+#ifdef DF_DEBUG_CFG
+ if (!df_lr->solutions_dirty)
+ df_set_clean_cfg ();
+#endif
+}
+
+
+/* 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_bb_replace (int old_index, basic_block new_block)
+{
+ int new_block_index = new_block->index;
+ int p;
+
+ if (dump_file)
+ fprintf (dump_file, "shoving block %d into %d\n", new_block_index, old_index);
+
+ gcc_assert (df);
+ gcc_assert (BASIC_BLOCK (old_index) == NULL);
+
+ for (p = 0; p < df->num_problems_defined; p++)
+ {
+ struct dataflow *dflow = df->problems_in_order[p];
+ if (dflow->block_info)
+ {
+ df_grow_bb_info (dflow);
+ gcc_assert (df_get_bb_info (dflow, old_index) == NULL);
+ df_set_bb_info (dflow, old_index,
+ df_get_bb_info (dflow, new_block_index));
+ }
+ }
+
+ df_clear_bb_dirty (new_block);
+ SET_BASIC_BLOCK (old_index, new_block);
+ new_block->index = old_index;
+ df_set_bb_dirty (BASIC_BLOCK (old_index));
+ SET_BASIC_BLOCK (new_block_index, NULL);
+}
+
+
+/* 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. */
+
+void
+df_bb_delete (int bb_index)
+{
+ basic_block bb = BASIC_BLOCK (bb_index);
+ int i;
+
+ if (!df)
+ return;
+
+ for (i = 0; i < df->num_problems_defined; i++)
+ {
+ struct dataflow *dflow = df->problems_in_order[i];
+ if (dflow->problem->free_bb_fun)
+ {
+ void *bb_info = df_get_bb_info (dflow, bb_index);
+ if (bb_info)
+ {
+ dflow->problem->free_bb_fun (bb, bb_info);
+ df_set_bb_info (dflow, bb_index, NULL);
+ }
+ }
+ }
+ df_clear_bb_dirty (bb);
+ df_mark_solutions_dirty ();
+}
+
+
+/* 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. */
+
+void
+df_verify (void)
+{
+ df_scan_verify ();
+#ifdef ENABLE_DF_CHECKING
+ df_lr_verify_transfer_functions ();
+ if (df_live)
+ df_live_verify_transfer_functions ();
+#endif
+}
+
+#ifdef DF_DEBUG_CFG
+
+/* 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. */
+
+static int *
+df_compute_cfg_image (void)
+{
+ basic_block bb;
+ int size = 2 + (2 * n_basic_blocks);
+ int i;
+ int * map;
+
+ FOR_ALL_BB (bb)
+ {
+ size += EDGE_COUNT (bb->succs);
+ }
+
+ map = XNEWVEC (int, size);
+ map[0] = size;
+ i = 1;
+ FOR_ALL_BB (bb)
+ {
+ edge_iterator ei;
+ edge e;
+
+ map[i++] = bb->index;
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ map[i++] = e->dest->index;
+ map[i++] = -1;
+ }
+ map[i] = -1;
+ return map;
+}
+
+static int *saved_cfg = NULL;
+
+
+/* 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. */
+
+void
+df_check_cfg_clean (void)
+{
+ int *new_map;
+
+ if (!df)
+ return;
+
+ if (df_lr->solutions_dirty)
+ return;
+
+ if (saved_cfg == NULL)
+ return;
+
+ new_map = df_compute_cfg_image ();
+ gcc_assert (memcmp (saved_cfg, new_map, saved_cfg[0] * sizeof (int)) == 0);
+ free (new_map);
+}
+
+
+/* This function builds a cfg fingerprint and squirrels it away in
+ saved_cfg. */
+
+static void
+df_set_clean_cfg (void)
+{
+ if (saved_cfg)
+ free (saved_cfg);
+ saved_cfg = df_compute_cfg_image ();
+}
+
+#endif /* DF_DEBUG_CFG */
+/*----------------------------------------------------------------------------
+ PUBLIC INTERFACES TO QUERY INFORMATION.
+----------------------------------------------------------------------------*/
+
+
+/* Return first def of REGNO within BB. */
+
+df_ref
+df_bb_regno_first_def_find (basic_block bb, unsigned int regno)
+{
+ rtx insn;
+ df_ref *def_rec;
+ unsigned int uid;
+
+ FOR_BB_INSNS (bb, insn)
+ {
+ if (!INSN_P (insn))
+ continue;
+
+ uid = INSN_UID (insn);
+ for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
+ {
+ df_ref def = *def_rec;
+ if (DF_REF_REGNO (def) == regno)
+ return def;
+ }
+ }
+ return NULL;
+}
+
+
+/* Return last def of REGNO within BB. */
+
+df_ref
+df_bb_regno_last_def_find (basic_block bb, unsigned int regno)
+{
+ rtx insn;
+ df_ref *def_rec;
+ unsigned int uid;
+
+ FOR_BB_INSNS_REVERSE (bb, insn)
+ {
+ if (!INSN_P (insn))
+ continue;
+
+ uid = INSN_UID (insn);
+ for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
+ {
+ df_ref def = *def_rec;
+ if (DF_REF_REGNO (def) == regno)
+ return def;
+ }
+ }
+
+ return NULL;
+}
+
+/* Finds the reference corresponding to the definition of REG in INSN.
+ DF is the dataflow object. */
+
+df_ref
+df_find_def (rtx insn, rtx reg)
+{
+ unsigned int uid;
+ df_ref *def_rec;
+
+ if (GET_CODE (reg) == SUBREG)
+ reg = SUBREG_REG (reg);
+ gcc_assert (REG_P (reg));
+
+ uid = INSN_UID (insn);
+ for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
+ {
+ df_ref def = *def_rec;
+ if (rtx_equal_p (DF_REF_REAL_REG (def), reg))
+ return def;
+ }
+
+ return NULL;
+}
+
+
+/* Return true if REG is defined in INSN, zero otherwise. */
+
+bool
+df_reg_defined (rtx insn, rtx reg)
+{
+ return df_find_def (insn, reg) != NULL;
+}
+
+
+/* Finds the reference corresponding to the use of REG in INSN.
+ DF is the dataflow object. */
+
+df_ref
+df_find_use (rtx insn, rtx reg)
+{
+ unsigned int uid;
+ df_ref *use_rec;
+
+ if (GET_CODE (reg) == SUBREG)
+ reg = SUBREG_REG (reg);
+ gcc_assert (REG_P (reg));
+
+ uid = INSN_UID (insn);
+ for (use_rec = DF_INSN_UID_USES (uid); *use_rec; use_rec++)
+ {
+ df_ref use = *use_rec;
+ if (rtx_equal_p (DF_REF_REAL_REG (use), reg))
+ return use;
+ }
+ if (df->changeable_flags & DF_EQ_NOTES)
+ for (use_rec = DF_INSN_UID_EQ_USES (uid); *use_rec; use_rec++)
+ {
+ df_ref use = *use_rec;
+ if (rtx_equal_p (DF_REF_REAL_REG (use), reg))
+ return use;
+ }
+ return NULL;
+}
+
+
+/* Return true if REG is referenced in INSN, zero otherwise. */
+
+bool
+df_reg_used (rtx insn, rtx reg)
+{
+ return df_find_use (insn, reg) != NULL;
+}
+
+
+/*----------------------------------------------------------------------------
+ Debugging and printing functions.
+----------------------------------------------------------------------------*/
+
+
+/* Write information about registers and basic blocks into FILE.
+ This is part of making a debugging dump. */
+
+void
+df_print_regset (FILE *file, bitmap r)
+{
+ unsigned int i;
+ bitmap_iterator bi;
+
+ if (r == NULL)
+ fputs (" (nil)", file);
+ else
+ {
+ EXECUTE_IF_SET_IN_BITMAP (r, 0, i, bi)
+ {
+ fprintf (file, " %d", i);
+ if (i < FIRST_PSEUDO_REGISTER)
+ fprintf (file, " [%s]", reg_names[i]);
+ }
+ }
+ fprintf (file, "\n");
+}
+
+
+/* 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. */
+
+void
+df_print_byte_regset (FILE *file, bitmap r)
+{
+ unsigned int max_reg = max_reg_num ();
+ bitmap_iterator bi;
+
+ if (r == NULL)
+ fputs (" (nil)", file);
+ else
+ {
+ unsigned int i;
+ for (i = 0; i < max_reg; i++)
+ {
+ unsigned int first = df_byte_lr_get_regno_start (i);
+ unsigned int len = df_byte_lr_get_regno_len (i);
+
+ if (len > 1)
+ {
+ bool found = false;
+ unsigned int j;
+
+ EXECUTE_IF_SET_IN_BITMAP (r, first, j, bi)
+ {
+ found = j < first + len;
+ break;
+ }
+ if (found)
+ {
+ const char * sep = "";
+ fprintf (file, " %d", i);
+ if (i < FIRST_PSEUDO_REGISTER)
+ fprintf (file, " [%s]", reg_names[i]);
+ fprintf (file, "(");
+ EXECUTE_IF_SET_IN_BITMAP (r, first, j, bi)
+ {
+ if (j > first + len - 1)
+ break;
+ fprintf (file, "%s%d", sep, j-first);
+ sep = ", ";
+ }
+ fprintf (file, ")");
+ }
+ }
+ else
+ {
+ if (bitmap_bit_p (r, first))
+ {
+ fprintf (file, " %d", i);
+ if (i < FIRST_PSEUDO_REGISTER)
+ fprintf (file, " [%s]", reg_names[i]);
+ }
+ }
+
+ }
+ }
+ fprintf (file, "\n");
+}
+
+
+/* Dump dataflow info. */
+
+void
+df_dump (FILE *file)
+{
+ basic_block bb;
+ df_dump_start (file);
+
+ FOR_ALL_BB (bb)
+ {
+ df_print_bb_index (bb, file);
+ df_dump_top (bb, file);
+ df_dump_bottom (bb, file);
+ }
+
+ fprintf (file, "\n");
+}
+
+
+/* Dump dataflow info for df->blocks_to_analyze. */
+
+void
+df_dump_region (FILE *file)
+{
+ if (df->blocks_to_analyze)
+ {
+ bitmap_iterator bi;
+ unsigned int bb_index;
+
+ fprintf (file, "\n\nstarting region dump\n");
+ df_dump_start (file);
+
+ EXECUTE_IF_SET_IN_BITMAP (df->blocks_to_analyze, 0, bb_index, bi)
+ {
+ basic_block bb = BASIC_BLOCK (bb_index);
+
+ df_print_bb_index (bb, file);
+ df_dump_top (bb, file);
+ df_dump_bottom (bb, file);
+ }
+ fprintf (file, "\n");
+ }
+ else
+ df_dump (file);
+}
+
+
+/* Dump the introductory information for each problem defined. */
+
+void
+df_dump_start (FILE *file)
+{
+ int i;
+
+ if (!df || !file)
+ return;
+
+ fprintf (file, "\n\n%s\n", current_function_name ());
+ fprintf (file, "\nDataflow summary:\n");
+ if (df->blocks_to_analyze)
+ fprintf (file, "def_info->table_size = %d, use_info->table_size = %d\n",
+ DF_DEFS_TABLE_SIZE (), DF_USES_TABLE_SIZE ());
+
+ for (i = 0; i < df->num_problems_defined; i++)
+ {
+ struct dataflow *dflow = df->problems_in_order[i];
+ if (dflow->computed)
+ {
+ df_dump_problem_function fun = dflow->problem->dump_start_fun;
+ if (fun)
+ fun(file);
+ }
+ }
+}
+
+
+/* Dump the top of the block information for BB. */
+
+void
+df_dump_top (basic_block bb, FILE *file)
+{
+ int i;
+
+ if (!df || !file)
+ return;
+
+ for (i = 0; i < df->num_problems_defined; i++)
+ {
+ struct dataflow *dflow = df->problems_in_order[i];
+ if (dflow->computed)
+ {
+ df_dump_bb_problem_function bbfun = dflow->problem->dump_top_fun;
+ if (bbfun)
+ bbfun (bb, file);
+ }
+ }
+}
+
+
+/* Dump the bottom of the block information for BB. */
+
+void
+df_dump_bottom (basic_block bb, FILE *file)
+{
+ int i;
+
+ if (!df || !file)
+ return;
+
+ for (i = 0; i < df->num_problems_defined; i++)
+ {
+ struct dataflow *dflow = df->problems_in_order[i];
+ if (dflow->computed)
+ {
+ df_dump_bb_problem_function bbfun = dflow->problem->dump_bottom_fun;
+ if (bbfun)
+ bbfun (bb, file);
+ }
+ }
+}
+
+
+void
+df_refs_chain_dump (df_ref *ref_rec, bool follow_chain, FILE *file)
+{
+ fprintf (file, "{ ");
+ while (*ref_rec)
+ {
+ df_ref ref = *ref_rec;
+ fprintf (file, "%c%d(%d)",
+ DF_REF_REG_DEF_P (ref) ? 'd' : (DF_REF_FLAGS (ref) & DF_REF_IN_NOTE) ? 'e' : 'u',
+ DF_REF_ID (ref),
+ DF_REF_REGNO (ref));
+ if (follow_chain)
+ df_chain_dump (DF_REF_CHAIN (ref), file);
+ ref_rec++;
+ }
+ fprintf (file, "}");
+}
+
+
+/* Dump either a ref-def or reg-use chain. */
+
+void
+df_regs_chain_dump (df_ref ref, FILE *file)
+{
+ fprintf (file, "{ ");
+ while (ref)
+ {
+ fprintf (file, "%c%d(%d) ",
+ DF_REF_REG_DEF_P (ref) ? 'd' : 'u',
+ DF_REF_ID (ref),
+ DF_REF_REGNO (ref));
+ ref = DF_REF_NEXT_REG (ref);
+ }
+ fprintf (file, "}");
+}
+
+
+static void
+df_mws_dump (struct df_mw_hardreg **mws, FILE *file)
+{
+ while (*mws)
+ {
+ fprintf (file, "mw %c r[%d..%d]\n",
+ (DF_MWS_REG_DEF_P (*mws)) ? 'd' : 'u',
+ (*mws)->start_regno, (*mws)->end_regno);
+ mws++;
+ }
+}
+
+
+static void
+df_insn_uid_debug (unsigned int uid,
+ bool follow_chain, FILE *file)
+{
+ fprintf (file, "insn %d luid %d",
+ uid, DF_INSN_UID_LUID (uid));
+
+ if (DF_INSN_UID_DEFS (uid))
+ {
+ fprintf (file, " defs ");
+ df_refs_chain_dump (DF_INSN_UID_DEFS (uid), follow_chain, file);
+ }
+
+ if (DF_INSN_UID_USES (uid))
+ {
+ fprintf (file, " uses ");
+ df_refs_chain_dump (DF_INSN_UID_USES (uid), follow_chain, file);
+ }
+
+ if (DF_INSN_UID_EQ_USES (uid))
+ {
+ fprintf (file, " eq uses ");
+ df_refs_chain_dump (DF_INSN_UID_EQ_USES (uid), follow_chain, file);
+ }
+
+ if (DF_INSN_UID_MWS (uid))
+ {
+ fprintf (file, " mws ");
+ df_mws_dump (DF_INSN_UID_MWS (uid), file);
+ }
+ fprintf (file, "\n");
+}
+
+
+void
+df_insn_debug (rtx insn, bool follow_chain, FILE *file)
+{
+ df_insn_uid_debug (INSN_UID (insn), follow_chain, file);
+}
+
+void
+df_insn_debug_regno (rtx insn, FILE *file)
+{
+ struct df_insn_info *insn_info = DF_INSN_INFO_GET (insn);
+
+ fprintf (file, "insn %d bb %d luid %d defs ",
+ INSN_UID (insn), BLOCK_FOR_INSN (insn)->index,
+ DF_INSN_INFO_LUID (insn_info));
+ df_refs_chain_dump (DF_INSN_INFO_DEFS (insn_info), false, file);
+
+ fprintf (file, " uses ");
+ df_refs_chain_dump (DF_INSN_INFO_USES (insn_info), false, file);
+
+ fprintf (file, " eq_uses ");
+ df_refs_chain_dump (DF_INSN_INFO_EQ_USES (insn_info), false, file);
+ fprintf (file, "\n");
+}
+
+void
+df_regno_debug (unsigned int regno, FILE *file)
+{
+ fprintf (file, "reg %d defs ", regno);
+ df_regs_chain_dump (DF_REG_DEF_CHAIN (regno), file);
+ fprintf (file, " uses ");
+ df_regs_chain_dump (DF_REG_USE_CHAIN (regno), file);
+ fprintf (file, " eq_uses ");
+ df_regs_chain_dump (DF_REG_EQ_USE_CHAIN (regno), file);
+ fprintf (file, "\n");
+}
+
+
+void
+df_ref_debug (df_ref ref, FILE *file)
+{
+ fprintf (file, "%c%d ",
+ DF_REF_REG_DEF_P (ref) ? 'd' : 'u',
+ DF_REF_ID (ref));
+ fprintf (file, "reg %d bb %d insn %d flag 0x%x type 0x%x ",
+ DF_REF_REGNO (ref),
+ DF_REF_BBNO (ref),
+ DF_REF_IS_ARTIFICIAL (ref) ? -1 : DF_REF_INSN_UID (ref),
+ DF_REF_FLAGS (ref),
+ DF_REF_TYPE (ref));
+ if (DF_REF_LOC (ref))
+ fprintf (file, "loc %p(%p) chain ", (void *)DF_REF_LOC (ref), (void *)*DF_REF_LOC (ref));
+ else
+ fprintf (file, "chain ");
+ df_chain_dump (DF_REF_CHAIN (ref), file);
+ fprintf (file, "\n");
+}
+
+/* Functions for debugging from GDB. */
+
+void
+debug_df_insn (rtx insn)
+{
+ df_insn_debug (insn, true, stderr);
+ debug_rtx (insn);
+}
+
+
+void
+debug_df_reg (rtx reg)
+{
+ df_regno_debug (REGNO (reg), stderr);
+}
+
+
+void
+debug_df_regno (unsigned int regno)
+{
+ df_regno_debug (regno, stderr);
+}
+
+
+void
+debug_df_ref (df_ref ref)
+{
+ df_ref_debug (ref, stderr);
+}
+
+
+void
+debug_df_defno (unsigned int defno)
+{
+ df_ref_debug (DF_DEFS_GET (defno), stderr);
+}
+
+
+void
+debug_df_useno (unsigned int defno)
+{
+ df_ref_debug (DF_USES_GET (defno), stderr);
+}
+
+
+void
+debug_df_chain (struct df_link *link)
+{
+ df_chain_dump (link, stderr);
+ fputc ('\n', stderr);
+}