xref: /openbsd/gnu/gcc/gcc/df.h (revision 404b540a)
1 /* Form lists of pseudo register references for autoinc optimization
2    for GNU compiler.  This is part of flow optimization.
3    Copyright (C) 1999, 2000, 2001, 2003, 2004, 2005, 2006
4    Free Software Foundation, Inc.
5    Originally contributed by Michael P. Hayes
6              (m.hayes@elec.canterbury.ac.nz, mhayes@redhat.com)
7    Major rewrite contributed by Danny Berlin (dberlin@dberlin.org)
8              and Kenneth Zadeck (zadeck@naturalbridge.com).
9 
10 This file is part of GCC.
11 
12 GCC is free software; you can redistribute it and/or modify it under
13 the terms of the GNU General Public License as published by the Free
14 Software Foundation; either version 2, or (at your option) any later
15 version.
16 
17 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
18 WARRANTY; without even the implied warranty of MERCHANTABILITY or
19 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
20 for more details.
21 
22 You should have received a copy of the GNU General Public License
23 along with GCC; see the file COPYING.  If not, write to the Free
24 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
25 02110-1301, USA.  */
26 
27 #ifndef GCC_DF_H
28 #define GCC_DF_H
29 
30 #include "bitmap.h"
31 #include "basic-block.h"
32 #include "alloc-pool.h"
33 
34 struct dataflow;
35 struct df;
36 struct df_problem;
37 struct df_link;
38 
39 /* Data flow problems.  All problems must have a unique here.  */
40 /* Scanning is not really a dataflow problem, but it is useful to have
41    the basic block functions in the vector so that things get done in
42    a uniform manner.  */
43 #define DF_SCAN  0
44 #define DF_RU    1      /* Reaching Uses. */
45 #define DF_RD    2      /* Reaching Defs. */
46 #define DF_LR    3      /* Live Registers. */
47 #define DF_UR    4      /* Uninitialized Registers. */
48 #define DF_UREC  5      /* Uninitialized Registers with Early Clobber. */
49 #define DF_CHAIN 6      /* Def-Use and/or Use-Def Chains. */
50 #define DF_RI    7      /* Register Info. */
51 #define DF_LAST_PROBLEM_PLUS1 (DF_RI + 1)
52 
53 
54 /* Dataflow direction.  */
55 enum df_flow_dir
56   {
57     DF_NONE,
58     DF_FORWARD,
59     DF_BACKWARD
60   };
61 
62 
63 /* The first of these is a set of a register.  The remaining three are
64    all uses of a register (the mem_load and mem_store relate to how
65    the register as an addressing operand).  */
66 enum df_ref_type {DF_REF_REG_DEF, DF_REF_REG_USE, DF_REF_REG_MEM_LOAD,
67 		  DF_REF_REG_MEM_STORE};
68 
69 #define DF_REF_TYPE_NAMES {"def", "use", "mem load", "mem store"}
70 
71 enum df_ref_flags
72   {
73     /* Read-modify-write refs generate both a use and a def and
74        these are marked with this flag to show that they are not
75        independent.  */
76     DF_REF_READ_WRITE = 1,
77 
78     /* This flag is set, if we stripped the subreg from the reference.
79        In this case we must make conservative guesses, at what the
80        outer mode was.  */
81     DF_REF_STRIPPED = 2,
82 
83     /* If this flag is set, this is not a real definition/use, but an
84        artificial one created to model always live registers, eh uses, etc.  */
85     DF_REF_ARTIFICIAL = 4,
86 
87 
88     /* If this flag is set for an artificial use or def, that ref
89        logically happens at the top of the block.  If it is not set
90        for an artificial use or def, that ref logically happens at the
91        bottom of the block.  This is never set for regular refs.  */
92     DF_REF_AT_TOP = 8,
93 
94     /* This flag is set if the use is inside a REG_EQUAL note.  */
95     DF_REF_IN_NOTE = 16,
96 
97     /* This flag is set if this ref, generally a def, may clobber the
98        referenced register.  This is generally only set for hard
99        registers that cross a call site.  With better information
100        about calls, some of these could be changed in the future to
101        DF_REF_MUST_CLOBBER.  */
102     DF_REF_MAY_CLOBBER = 32,
103 
104     /* This flag is set if this ref, generally a def, is a real
105        clobber. This is not currently set for registers live across a
106        call because that clobbering may or may not happen.
107 
108        Most of the uses of this are with sets that have a
109        GET_CODE(..)==CLOBBER.  Note that this is set even if the
110        clobber is to a subreg.  So in order to tell if the clobber
111        wipes out the entire register, it is necessary to also check
112        the DF_REF_PARTIAL flag.  */
113     DF_REF_MUST_CLOBBER = 64,
114 
115     /* This bit is true if this ref is part of a multiword hardreg.  */
116     DF_REF_MW_HARDREG = 128,
117 
118     /* This flag is set if this ref is a partial use or def of the
119        associated register.  */
120     DF_REF_PARTIAL = 256
121   };
122 
123 
124 /* Function prototypes added to df_problem instance.  */
125 
126 /* Allocate the problem specific data.  */
127 typedef void (*df_alloc_function) (struct dataflow *, bitmap, bitmap);
128 
129 /* This function is called if the problem has global data that needs
130    to be cleared when ever the set of blocks changes.  The bitmap
131    contains the set of blocks that may require special attention.
132    This call is only made if some of the blocks are going to change.
133    If everything is to be deleted, the wholesale deletion mechanisms
134    apply. */
135 typedef void (*df_reset_function) (struct dataflow *, bitmap);
136 
137 /* Free the basic block info.  Called from the block reordering code
138    to get rid of the blocks that have been squished down.   */
139 typedef void (*df_free_bb_function) (struct dataflow *, basic_block, void *);
140 
141 /* Local compute function.  */
142 typedef void (*df_local_compute_function) (struct dataflow *, bitmap, bitmap);
143 
144 /* Init the solution specific data.  */
145 typedef void (*df_init_function) (struct dataflow *, bitmap);
146 
147 /* Iterative dataflow function.  */
148 typedef void (*df_dataflow_function) (struct dataflow *, bitmap, bitmap,
149 				   int *, int, bool);
150 
151 /* Confluence operator for blocks with 0 out (or in) edges.  */
152 typedef void (*df_confluence_function_0) (struct dataflow *, basic_block);
153 
154 /* Confluence operator for blocks with 1 or more out (or in) edges.  */
155 typedef void (*df_confluence_function_n) (struct dataflow *, edge);
156 
157 /* Transfer function for blocks.  */
158 typedef bool (*df_transfer_function) (struct dataflow *, int);
159 
160 /* Function to massage the information after the problem solving.  */
161 typedef void (*df_finalizer_function) (struct dataflow*, bitmap);
162 
163 /* Function to free all of the problem specific datastructures.  */
164 typedef void (*df_free_function) (struct dataflow *);
165 
166 /* Function to dump results to FILE.  */
167 typedef void (*df_dump_problem_function) (struct dataflow *, FILE *);
168 
169 /* Function to add problem a dataflow problem that must be solved
170    before this problem can be solved.  */
171 typedef struct dataflow * (*df_dependent_problem_function) (struct df *, int);
172 
173 /* The static description of a dataflow problem to solve.  See above
174    typedefs for doc for the function fields.  */
175 
176 struct df_problem {
177   /* The unique id of the problem.  This is used it index into
178      df->defined_problems to make accessing the problem data easy.  */
179   unsigned int id;
180   enum df_flow_dir dir;			/* Dataflow direction.  */
181   df_alloc_function alloc_fun;
182   df_reset_function reset_fun;
183   df_free_bb_function free_bb_fun;
184   df_local_compute_function local_compute_fun;
185   df_init_function init_fun;
186   df_dataflow_function dataflow_fun;
187   df_confluence_function_0 con_fun_0;
188   df_confluence_function_n con_fun_n;
189   df_transfer_function trans_fun;
190   df_finalizer_function finalize_fun;
191   df_free_function free_fun;
192   df_dump_problem_function dump_fun;
193   df_dependent_problem_function dependent_problem_fun;
194 
195   /* Flags can be changed after analysis starts.  */
196   int changeable_flags;
197 };
198 
199 
200 /* The specific instance of the problem to solve.  */
201 struct dataflow
202 {
203   struct df *df;                        /* Instance of df we are working in.  */
204   struct df_problem *problem;           /* The problem to be solved.  */
205 
206   /* Communication between iterative_dataflow and hybrid_search. */
207   sbitmap visited, pending, considered;
208 
209   /* Array indexed by bb->index, that contains basic block problem and
210      solution specific information.  */
211   void **block_info;
212   unsigned int block_info_size;
213 
214   /* The pool to allocate the block_info from. */
215   alloc_pool block_pool;
216 
217   /* Problem specific control information.  */
218 
219   /* Scanning flags.  */
220 #define DF_HARD_REGS	     1	/* Mark hard registers.  */
221 #define DF_EQUIV_NOTES	     2	/* Mark uses present in EQUIV/EQUAL notes.  */
222 #define DF_SUBREGS	     4	/* Return subregs rather than the inner reg.  */
223   /* Flags that control the building of chains.  */
224 #define DF_DU_CHAIN          1    /* Build DU chains.  */
225 #define DF_UD_CHAIN          2    /* Build UD chains.  */
226   /* Flag to control the building of register info.  */
227 #define DF_RI_LIFE           1    /* Build register info.  */
228 
229   int flags;
230 
231   /* Other problem specific data that is not on a per basic block
232      basis.  The structure is generally defined privately for the
233      problem.  The exception being the scanning problem where it is
234      fully public.  */
235   void *problem_data;
236 };
237 
238 
239 /* The set of multiword hardregs used as operands to this
240    instruction. These are factored into individual uses and defs but
241    the aggregate is still needed to service the REG_DEAD and
242    REG_UNUSED notes.  */
243 struct df_mw_hardreg
244 {
245   rtx mw_reg;                   /* The multiword hardreg.  */
246   enum df_ref_type type;        /* Used to see if the ref is read or write.  */
247   enum df_ref_flags flags;	/* Various flags.  */
248   struct df_link *regs;         /* The individual regs that make up
249 				   this hardreg.  */
250   struct df_mw_hardreg *next;   /* The next mw_hardreg in this insn.  */
251 };
252 
253 
254 /* One of these structures is allocated for every insn.  */
255 struct df_insn_info
256 {
257   struct df_ref *defs;	        /* Head of insn-def chain.  */
258   struct df_ref *uses;	        /* Head of insn-use chain.  */
259   struct df_mw_hardreg *mw_hardregs;
260   /* ???? The following luid field should be considered private so that
261      we can change it on the fly to accommodate new insns?  */
262   int luid;			/* Logical UID.  */
263   bool contains_asm;            /* Contains an asm instruction.  */
264 };
265 
266 
267 /* Two of these structures are allocated for every pseudo reg, one for
268    the uses and one for the defs.  */
269 struct df_reg_info
270 {
271   struct df_ref *reg_chain;     /* Head of reg-use or def chain.  */
272   unsigned int begin;           /* First def_index for this pseudo.  */
273   unsigned int n_refs;          /* Number of refs or defs for this pseudo.  */
274 };
275 
276 /* Define a register reference structure.  One of these is allocated
277    for every register reference (use or def).  Note some register
278    references (e.g., post_inc, subreg) generate both a def and a use.  */
279 struct df_ref
280 {
281   rtx reg;			/* The register referenced.  */
282   unsigned int regno;           /* The register number referenced.  */
283   basic_block bb;               /* Basic block containing the instruction. */
284 
285   /* Insn containing ref. This will be null if this is an artificial
286      reference.  */
287   rtx insn;
288   rtx *loc;			/* The location of the reg.  */
289   struct df_link *chain;	/* Head of def-use, use-def.  */
290   unsigned int id;		/* Location in table.  */
291   enum df_ref_type type;	/* Type of ref.  */
292   enum df_ref_flags flags;	/* Various flags.  */
293 
294   /* For each regno, there are two chains of refs, one for the uses
295      and one for the defs.  These chains go thru the refs themselves
296      rather than using an external structure.  */
297   struct df_ref *next_reg;     /* Next ref with same regno and type.  */
298   struct df_ref *prev_reg;     /* Prev ref with same regno and type.  */
299 
300   /* Each insn has two lists, one for the uses and one for the
301      defs. This is the next field in either of these chains. */
302   struct df_ref *next_ref;
303   void *data;			/* The data assigned to it by user.  */
304 };
305 
306 /* These links are used for two purposes:
307    1) def-use or use-def chains.
308    2) Multiword hard registers that underly a single hardware register.  */
309 struct df_link
310 {
311   struct df_ref *ref;
312   struct df_link *next;
313 };
314 
315 /* Two of these structures are allocated, one for the uses and one for
316    the defs.  */
317 struct df_ref_info
318 {
319   struct df_reg_info **regs;    /* Array indexed by pseudo regno. */
320   unsigned int regs_size;       /* Size of currently allocated regs table.  */
321   unsigned int regs_inited;     /* Number of regs with reg_infos allocated.  */
322   struct df_ref **refs;         /* Ref table, indexed by id.  */
323   unsigned int refs_size;       /* Size of currently allocated refs table.  */
324   unsigned int bitmap_size;	/* Number of refs seen.  */
325 
326   /* True if refs table is organized so that every reference for a
327      pseudo is contiguous.  */
328   bool refs_organized;
329   /* True if the next refs should be added immediately or false to
330      defer to later to reorganize the table.  */
331   bool add_refs_inline;
332 };
333 
334 
335 /*----------------------------------------------------------------------------
336    Problem data for the scanning dataflow problem.  Unlike the other
337    dataflow problems, the problem data for scanning is fully exposed and
338    used by owners of the problem.
339 ----------------------------------------------------------------------------*/
340 
341 struct df
342 {
343 
344   /* The set of problems to be solved is stored in two arrays.  In
345      PROBLEMS_IN_ORDER, the problems are stored in the order that they
346      are solved.  This is an internally dense array that may have
347      nulls at the end of it.  In PROBLEMS_BY_INDEX, the problem is
348      stored by the value in df_problem.id.  These are used to access
349      the problem local data without having to search the first
350      array.  */
351 
352   struct dataflow *problems_in_order [DF_LAST_PROBLEM_PLUS1];
353   struct dataflow *problems_by_index [DF_LAST_PROBLEM_PLUS1];
354   int num_problems_defined;
355 
356   /* Set after calls to df_scan_blocks, this contains all of the
357      blocks that higher level problems must rescan before solving the
358      dataflow equations.  If this is NULL, the blocks_to_analyze is
359      used. */
360   bitmap blocks_to_scan;
361 
362   /* If not NULL, the subset of blocks of the program to be considered
363      for analysis.  */
364   bitmap blocks_to_analyze;
365 
366   /* The following information is really the problem data for the
367      scanning instance but it is used too often by the other problems
368      to keep getting it from there.  */
369   struct df_ref_info def_info;   /* Def info.  */
370   struct df_ref_info use_info;   /* Use info.  */
371   struct df_insn_info **insns;   /* Insn table, indexed by insn UID.  */
372   unsigned int insns_size;       /* Size of insn table.  */
373   bitmap hardware_regs_used;     /* The set of hardware registers used.  */
374   bitmap entry_block_defs;       /* The set of hardware registers live on entry to the function.  */
375   bitmap exit_block_uses;        /* The set of hardware registers used in exit block.  */
376 };
377 
378 #define DF_SCAN_BB_INFO(DF, BB) (df_scan_get_bb_info((DF)->problems_by_index[DF_SCAN],(BB)->index))
379 #define DF_RU_BB_INFO(DF, BB) (df_ru_get_bb_info((DF)->problems_by_index[DF_RU],(BB)->index))
380 #define DF_RD_BB_INFO(DF, BB) (df_rd_get_bb_info((DF)->problems_by_index[DF_RD],(BB)->index))
381 #define DF_LR_BB_INFO(DF, BB) (df_lr_get_bb_info((DF)->problems_by_index[DF_LR],(BB)->index))
382 #define DF_UR_BB_INFO(DF, BB) (df_ur_get_bb_info((DF)->problems_by_index[DF_UR],(BB)->index))
383 #define DF_UREC_BB_INFO(DF, BB) (df_urec_get_bb_info((DF)->problems_by_index[DF_UREC],(BB)->index))
384 
385 /* Most transformations that wish to use live register analysis will
386    use these macros.  The DF_UPWARD_LIVE* macros are only half of the
387    solution.  */
388 #define DF_LIVE_IN(DF, BB) (DF_UR_BB_INFO(DF, BB)->in)
389 #define DF_LIVE_OUT(DF, BB) (DF_UR_BB_INFO(DF, BB)->out)
390 
391 
392 /* Live in for register allocation also takes into account several other factors.  */
393 #define DF_RA_LIVE_IN(DF, BB) (DF_UREC_BB_INFO(DF, BB)->in)
394 #define DF_RA_LIVE_OUT(DF, BB) (DF_UREC_BB_INFO(DF, BB)->out)
395 
396 /* These macros are currently used by only reg-stack since it is not
397    tolerant of uninitialized variables.  This intolerance should be
398    fixed because it causes other problems.  */
399 #define DF_UPWARD_LIVE_IN(DF, BB) (DF_LR_BB_INFO(DF, BB)->in)
400 #define DF_UPWARD_LIVE_OUT(DF, BB) (DF_LR_BB_INFO(DF, BB)->out)
401 
402 
403 /* Macros to access the elements within the ref structure.  */
404 
405 
406 #define DF_REF_REAL_REG(REF) (GET_CODE ((REF)->reg) == SUBREG \
407 				? SUBREG_REG ((REF)->reg) : ((REF)->reg))
408 #define DF_REF_REGNO(REF) ((REF)->regno)
409 #define DF_REF_REAL_LOC(REF) (GET_CODE ((REF)->reg) == SUBREG \
410 			        ? &SUBREG_REG ((REF)->reg) : ((REF)->loc))
411 #define DF_REF_REG(REF) ((REF)->reg)
412 #define DF_REF_LOC(REF) ((REF)->loc)
413 #define DF_REF_BB(REF) ((REF)->bb)
414 #define DF_REF_BBNO(REF) (DF_REF_BB (REF)->index)
415 #define DF_REF_INSN(REF) ((REF)->insn)
416 #define DF_REF_INSN_UID(REF) (INSN_UID ((REF)->insn))
417 #define DF_REF_TYPE(REF) ((REF)->type)
418 #define DF_REF_CHAIN(REF) ((REF)->chain)
419 #define DF_REF_ID(REF) ((REF)->id)
420 #define DF_REF_FLAGS(REF) ((REF)->flags)
421 #define DF_REF_NEXT_REG(REF) ((REF)->next_reg)
422 #define DF_REF_PREV_REG(REF) ((REF)->prev_reg)
423 #define DF_REF_NEXT_REF(REF) ((REF)->next_ref)
424 #define DF_REF_DATA(REF) ((REF)->data)
425 
426 /* Macros to determine the reference type.  */
427 
428 #define DF_REF_REG_DEF_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_DEF)
429 #define DF_REF_REG_USE_P(REF) ((REF) && !DF_REF_REG_DEF_P (REF))
430 #define DF_REF_REG_MEM_STORE_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_MEM_STORE)
431 #define DF_REF_REG_MEM_LOAD_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_MEM_LOAD)
432 #define DF_REF_REG_MEM_P(REF) (DF_REF_REG_MEM_STORE_P (REF) \
433                                || DF_REF_REG_MEM_LOAD_P (REF))
434 
435 /* Macros to get the refs out of def_info or use_info refs table.  */
436 #define DF_DEFS_SIZE(DF) ((DF)->def_info.bitmap_size)
437 #define DF_DEFS_GET(DF,ID) ((DF)->def_info.refs[(ID)])
438 #define DF_DEFS_SET(DF,ID,VAL) ((DF)->def_info.refs[(ID)]=(VAL))
439 #define DF_USES_SIZE(DF) ((DF)->use_info.bitmap_size)
440 #define DF_USES_GET(DF,ID) ((DF)->use_info.refs[(ID)])
441 #define DF_USES_SET(DF,ID,VAL) ((DF)->use_info.refs[(ID)]=(VAL))
442 
443 /* Macros to access the register information from scan dataflow record.  */
444 
445 #define DF_REG_SIZE(DF) ((DF)->def_info.regs_inited)
446 #define DF_REG_DEF_GET(DF, REG) ((DF)->def_info.regs[(REG)])
447 #define DF_REG_DEF_SET(DF, REG, VAL) ((DF)->def_info.regs[(REG)]=(VAL))
448 #define DF_REG_DEF_COUNT(DF, REG) ((DF)->def_info.regs[(REG)]->n_refs)
449 #define DF_REG_USE_GET(DF, REG) ((DF)->use_info.regs[(REG)])
450 #define DF_REG_USE_SET(DF, REG, VAL) ((DF)->use_info.regs[(REG)]=(VAL))
451 #define DF_REG_USE_COUNT(DF, REG) ((DF)->use_info.regs[(REG)]->n_refs)
452 
453 /* Macros to access the elements within the reg_info structure table.  */
454 
455 #define DF_REGNO_FIRST_DEF(DF, REGNUM) \
456 (DF_REG_DEF_GET(DF, REGNUM) ? DF_REG_DEF_GET(DF, REGNUM) : 0)
457 #define DF_REGNO_LAST_USE(DF, REGNUM) \
458 (DF_REG_USE_GET(DF, REGNUM) ? DF_REG_USE_GET(DF, REGNUM) : 0)
459 
460 /* Macros to access the elements within the insn_info structure table.  */
461 
462 #define DF_INSN_SIZE(DF) ((DF)->insns_size)
463 #define DF_INSN_GET(DF,INSN) ((DF)->insns[(INSN_UID(INSN))])
464 #define DF_INSN_SET(DF,INSN,VAL) ((DF)->insns[(INSN_UID (INSN))]=(VAL))
465 #define DF_INSN_CONTAINS_ASM(DF, INSN) (DF_INSN_GET(DF,INSN)->contains_asm)
466 #define DF_INSN_LUID(DF, INSN) (DF_INSN_GET(DF,INSN)->luid)
467 #define DF_INSN_DEFS(DF, INSN) (DF_INSN_GET(DF,INSN)->defs)
468 #define DF_INSN_USES(DF, INSN) (DF_INSN_GET(DF,INSN)->uses)
469 
470 #define DF_INSN_UID_GET(DF,UID) ((DF)->insns[(UID)])
471 #define DF_INSN_UID_LUID(DF, INSN) (DF_INSN_UID_GET(DF,INSN)->luid)
472 #define DF_INSN_UID_DEFS(DF, INSN) (DF_INSN_UID_GET(DF,INSN)->defs)
473 #define DF_INSN_UID_USES(DF, INSN) (DF_INSN_UID_GET(DF,INSN)->uses)
474 #define DF_INSN_UID_MWS(DF, INSN) (DF_INSN_UID_GET(DF,INSN)->mw_hardregs)
475 
476 /* This is a bitmap copy of regs_invalidated_by_call so that we can
477    easily add it into bitmaps, etc. */
478 
479 extern bitmap df_invalidated_by_call;
480 
481 
482 /* One of these structures is allocated for every basic block.  */
483 struct df_scan_bb_info
484 {
485   /* Defs at the start of a basic block that is the target of an
486      exception edge.  */
487   struct df_ref *artificial_defs;
488 
489   /* Uses of hard registers that are live at every block.  */
490   struct df_ref *artificial_uses;
491 };
492 
493 
494 /* Reaching uses.  All bitmaps are indexed by the id field of the ref
495    except sparse_kill (see below).  */
496 struct df_ru_bb_info
497 {
498   /* Local sets to describe the basic blocks.  */
499   /* The kill set is the set of uses that are killed in this block.
500      However, if the number of uses for this register is greater than
501      DF_SPARSE_THRESHOLD, the sparse_kill is used instead. In
502      sparse_kill, each register gets a slot and a 1 in this bitvector
503      means that all of the uses of that register are killed.  This is
504      a very useful efficiency hack in that it keeps from having push
505      around big groups of 1s.  This is implemented by the
506      bitmap_clear_range call.  */
507 
508   bitmap kill;
509   bitmap sparse_kill;
510   bitmap gen;   /* The set of uses generated in this block.  */
511 
512   /* The results of the dataflow problem.  */
513   bitmap in;    /* At the top of the block.  */
514   bitmap out;   /* At the bottom of the block.  */
515 };
516 
517 
518 /* Reaching definitions.  All bitmaps are indexed by the id field of
519    the ref except sparse_kill (see above).  */
520 struct df_rd_bb_info
521 {
522   /* Local sets to describe the basic blocks.  See the note in the RU
523      datastructures for kill and sparse_kill.  */
524   bitmap kill;
525   bitmap sparse_kill;
526   bitmap gen;   /* The set of defs generated in this block.  */
527 
528   /* The results of the dataflow problem.  */
529   bitmap in;    /* At the top of the block.  */
530   bitmap out;   /* At the bottom of the block.  */
531 };
532 
533 
534 /* Live registers.  All bitmaps are referenced by the register number.  */
535 struct df_lr_bb_info
536 {
537   /* Local sets to describe the basic blocks.  */
538   bitmap def;   /* The set of registers set in this block.  */
539   bitmap use;   /* The set of registers used in this block.  */
540 
541   /* The results of the dataflow problem.  */
542   bitmap in;    /* At the top of the block.  */
543   bitmap out;   /* At the bottom of the block.  */
544 };
545 
546 
547 /* Uninitialized registers.  All bitmaps are referenced by the register number.  */
548 struct df_ur_bb_info
549 {
550   /* Local sets to describe the basic blocks.  */
551   bitmap kill;  /* The set of registers unset in this block.  Calls,
552 		   for instance, unset registers.  */
553   bitmap gen;   /* The set of registers set in this block.  */
554 
555   /* The results of the dataflow problem.  */
556   bitmap in;    /* At the top of the block.  */
557   bitmap out;   /* At the bottom of the block.  */
558 };
559 
560 /* Uninitialized registers.  All bitmaps are referenced by the register number.  */
561 struct df_urec_bb_info
562 {
563   /* Local sets to describe the basic blocks.  */
564   bitmap earlyclobber;  /* The set of registers that are referenced
565 			   with an an early clobber mode.  */
566   /* Kill and gen are defined as in the UR problem.  */
567   bitmap kill;
568   bitmap gen;
569 
570   /* The results of the dataflow problem.  */
571   bitmap in;    /* At the top of the block.  */
572   bitmap out;   /* At the bottom of the block.  */
573 };
574 
575 
576 #define df_finish(df) {df_finish1(df); df=NULL;}
577 
578 /* Functions defined in df-core.c.  */
579 
580 extern struct df *df_init (int);
581 extern struct dataflow *df_add_problem (struct df *, struct df_problem *, int);
582 extern int df_set_flags (struct dataflow *, int);
583 extern int df_clear_flags (struct dataflow *, int);
584 extern void df_set_blocks (struct df*, bitmap);
585 extern void df_delete_basic_block (struct df *, int);
586 extern void df_finish1 (struct df *);
587 extern void df_analyze_problem (struct dataflow *, bitmap, bitmap, bitmap, int *, int, bool);
588 extern void df_analyze (struct df *);
589 extern void df_compact_blocks (struct df *);
590 extern void df_bb_replace (struct df *, int, basic_block);
591 extern struct df_ref *df_bb_regno_last_use_find (struct df *, basic_block, unsigned int);
592 extern struct df_ref *df_bb_regno_first_def_find (struct df *, basic_block, unsigned int);
593 extern struct df_ref *df_bb_regno_last_def_find (struct df *, basic_block, unsigned int);
594 extern bool df_insn_regno_def_p (struct df *, rtx, unsigned int);
595 extern struct df_ref *df_find_def (struct df *, rtx, rtx);
596 extern bool df_reg_defined (struct df *, rtx, rtx);
597 extern struct df_ref *df_find_use (struct df *, rtx, rtx);
598 extern bool df_reg_used (struct df *, rtx, rtx);
599 extern void df_iterative_dataflow (struct dataflow *, bitmap, bitmap, int *, int, bool);
600 extern void df_dump (struct df *, FILE *);
601 extern void df_refs_chain_dump (struct df_ref *, bool, FILE *);
602 extern void df_regs_chain_dump (struct df *, struct df_ref *,  FILE *);
603 extern void df_insn_debug (struct df *, rtx, bool, FILE *);
604 extern void df_insn_debug_regno (struct df *, rtx, FILE *);
605 extern void df_regno_debug (struct df *, unsigned int, FILE *);
606 extern void df_ref_debug (struct df_ref *, FILE *);
607 extern void debug_df_insn (rtx);
608 extern void debug_df_regno (unsigned int);
609 extern void debug_df_reg (rtx);
610 extern void debug_df_defno (unsigned int);
611 extern void debug_df_useno (unsigned int);
612 extern void debug_df_ref (struct df_ref *);
613 extern void debug_df_chain (struct df_link *);
614 /* An instance of df that can be shared between passes.  */
615 extern struct df *shared_df;
616 
617 
618 /* Functions defined in df-problems.c. */
619 
620 extern struct df_link *df_chain_create (struct dataflow *, struct df_ref *, struct df_ref *);
621 extern void df_chain_unlink (struct dataflow *, struct df_ref *, struct df_link *);
622 extern void df_chain_copy (struct dataflow *, struct df_ref *, struct df_link *);
623 extern bitmap df_get_live_in (struct df *, basic_block);
624 extern bitmap df_get_live_out (struct df *, basic_block);
625 extern void df_grow_bb_info (struct dataflow *);
626 extern void df_chain_dump (struct df_link *, FILE *);
627 extern void df_print_bb_index (basic_block bb, FILE *file);
628 extern struct dataflow *df_ru_add_problem (struct df *, int);
629 extern struct df_ru_bb_info *df_ru_get_bb_info (struct dataflow *, unsigned int);
630 extern struct dataflow *df_rd_add_problem (struct df *, int);
631 extern struct df_rd_bb_info *df_rd_get_bb_info (struct dataflow *, unsigned int);
632 extern struct dataflow *df_lr_add_problem (struct df *, int);
633 extern struct df_lr_bb_info *df_lr_get_bb_info (struct dataflow *, unsigned int);
634 extern struct dataflow *df_ur_add_problem (struct df *, int);
635 extern struct df_ur_bb_info *df_ur_get_bb_info (struct dataflow *, unsigned int);
636 extern struct dataflow *df_urec_add_problem (struct df *, int);
637 extern struct df_urec_bb_info *df_urec_get_bb_info (struct dataflow *, unsigned int);
638 extern struct dataflow *df_chain_add_problem (struct df *, int);
639 extern struct dataflow *df_ri_add_problem (struct df *, int);
640 
641 
642 /* Functions defined in df-scan.c.  */
643 
644 extern struct df_scan_bb_info *df_scan_get_bb_info (struct dataflow *, unsigned int);
645 extern struct dataflow *df_scan_add_problem (struct df *, int);
646 extern void df_rescan_blocks (struct df *, bitmap);
647 extern struct df_ref *df_ref_create (struct df *, rtx, rtx *, rtx,basic_block,enum df_ref_type, enum df_ref_flags);
648 extern struct df_ref *df_get_artificial_defs (struct df *, unsigned int);
649 extern struct df_ref *df_get_artificial_uses (struct df *, unsigned int);
650 extern void df_reg_chain_create (struct df_reg_info *, struct df_ref *);
651 extern struct df_ref *df_reg_chain_unlink (struct dataflow *, struct df_ref *);
652 extern void df_ref_remove (struct df *, struct df_ref *);
653 extern void df_insn_refs_delete (struct dataflow *, rtx);
654 extern void df_bb_refs_delete (struct dataflow *, int);
655 extern void df_refs_delete (struct dataflow *, bitmap);
656 extern void df_reorganize_refs (struct df_ref_info *);
657 extern void df_hard_reg_init (void);
658 extern bool df_read_modify_subreg_p (rtx);
659 
660 
661 /* web */
662 
663 /* This entry is allocated for each reference in the insn stream.  */
664 struct web_entry
665 {
666   /* Pointer to the parent in the union/find tree.  */
667   struct web_entry *pred;
668   /* Newly assigned register to the entry.  Set only for roots.  */
669   rtx reg;
670   void* extra_info;
671 };
672 
673 extern struct web_entry *unionfind_root (struct web_entry *);
674 extern bool unionfind_union (struct web_entry *, struct web_entry *);
675 extern void union_defs (struct df *, struct df_ref *,
676                         struct web_entry *, struct web_entry *,
677 			bool (*fun) (struct web_entry *, struct web_entry *));
678 
679 
680 #endif /* GCC_DF_H */
681