Fix a bug that broke -freorder-functions
[official-gcc.git] / gcc / ipa-prop.h
blob994e4ac146d660f1fe646dcb484aef29cd27b79b
1 /* Interprocedural analyses.
2 Copyright (C) 2005, 2007, 2008, 2009, 2010
3 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
21 #ifndef IPA_PROP_H
22 #define IPA_PROP_H
24 #include "tree.h"
25 #include "vec.h"
26 #include "cgraph.h"
27 #include "gimple.h"
28 #include "alloc-pool.h"
30 /* The following definitions and interfaces are used by
31 interprocedural analyses or parameters. */
33 /* ipa-prop.c stuff (ipa-cp, indirect inlining): */
35 /* A jump function for a callsite represents the values passed as actual
36 arguments of the callsite. They were originally proposed in a paper called
37 "Interprocedural Constant Propagation", by David Callahan, Keith D Cooper,
38 Ken Kennedy, Linda Torczon in Comp86, pg 152-161. There are three main
39 types of values :
41 Pass-through - the caller's formal parameter is passed as an actual
42 argument, possibly one simple operation performed on it.
43 Constant - a constant (is_gimple_ip_invariant)is passed as an actual
44 argument.
45 Unknown - neither of the above.
47 IPA_JF_CONST_MEMBER_PTR stands for C++ member pointers, it is a special
48 constant in this regard because it is in fact a structure consisting of two
49 values. Other constants are represented with IPA_JF_CONST.
51 IPA_JF_ANCESTOR is a special pass-through jump function, which means that
52 the result is an address of a part of the object pointed to by the formal
53 parameter to which the function refers. It is mainly intended to represent
54 getting addresses of of ancestor fields in C++
55 (e.g. &this_1(D)->D.1766.D.1756). Note that if the original pointer is
56 NULL, ancestor jump function must behave like a simple pass-through.
58 Other pass-through functions can either simply pass on an unchanged formal
59 parameter or can apply one simple binary operation to it (such jump
60 functions are called polynomial).
62 IPA_JF_KNOWN_TYPE is a special type of an "unknown" function that applies
63 only to pointer parameters. It means that even though we cannot prove that
64 the passed value is an interprocedural constant, we still know the exact
65 type of the containing object which may be valuable for devirtualization.
67 Jump functions are computed in ipa-prop.c by function
68 update_call_notes_after_inlining. Some information can be lost and jump
69 functions degraded accordingly when inlining, see
70 update_call_notes_after_inlining in the same file. */
72 enum jump_func_type
74 IPA_JF_UNKNOWN = 0, /* newly allocated and zeroed jump functions default */
75 IPA_JF_KNOWN_TYPE, /* represented by field base_binfo */
76 IPA_JF_CONST, /* represented by field costant */
77 IPA_JF_CONST_MEMBER_PTR, /* represented by field member_cst */
78 IPA_JF_PASS_THROUGH, /* represented by field pass_through */
79 IPA_JF_ANCESTOR /* represented by field ancestor */
82 /* Structure holding data required to describe a pass-through jump function. */
84 struct GTY(()) ipa_pass_through_data
86 /* If an operation is to be performed on the original parameter, this is the
87 second (constant) operand. */
88 tree operand;
89 /* Number of the caller's formal parameter being passed. */
90 int formal_id;
91 /* Operation that is performed on the argument before it is passed on.
92 NOP_EXPR means no operation. Otherwise oper must be a simple binary
93 arithmetic operation where the caller's parameter is the first operand and
94 operand field from this structure is the second one. */
95 enum tree_code operation;
98 /* Structure holding data required to describe an ancestor pass-through
99 jump function. */
101 struct GTY(()) ipa_ancestor_jf_data
103 /* Offset of the field representing the ancestor. */
104 HOST_WIDE_INT offset;
105 /* TYpe of the result. */
106 tree type;
107 /* Number of the caller's formal parameter being passed. */
108 int formal_id;
111 /* Structure holding a C++ member pointer constant. Holds a pointer to the
112 method and delta offset. */
113 struct GTY(()) ipa_member_ptr_cst
115 tree pfn;
116 tree delta;
119 /* A jump function for a callsite represents the values passed as actual
120 arguments of the callsite. See enum jump_func_type for the various
121 types of jump functions supported. */
122 struct GTY (()) ipa_jump_func
124 enum jump_func_type type;
125 /* Represents a value of a jump function. pass_through is used only in jump
126 function context. constant represents the actual constant in constant jump
127 functions and member_cst holds constant c++ member functions. */
128 union jump_func_value
130 tree GTY ((tag ("IPA_JF_KNOWN_TYPE"))) base_binfo;
131 tree GTY ((tag ("IPA_JF_CONST"))) constant;
132 struct ipa_member_ptr_cst GTY ((tag ("IPA_JF_CONST_MEMBER_PTR"))) member_cst;
133 struct ipa_pass_through_data GTY ((tag ("IPA_JF_PASS_THROUGH"))) pass_through;
134 struct ipa_ancestor_jf_data GTY ((tag ("IPA_JF_ANCESTOR"))) ancestor;
135 } GTY ((desc ("%1.type"))) value;
138 /* Summary describing a single formal parameter. */
140 struct ipa_param_descriptor
142 /* PARAM_DECL of this parameter. */
143 tree decl;
144 /* The parameter is used. */
145 unsigned used : 1;
148 typedef struct ipa_param_descriptor ipa_param_descriptor_t;
149 DEF_VEC_O (ipa_param_descriptor_t);
150 DEF_VEC_ALLOC_O (ipa_param_descriptor_t, heap);
151 struct ipcp_lattice;
153 /* ipa_node_params stores information related to formal parameters of functions
154 and some other information for interprocedural passes that operate on
155 parameters (such as ipa-cp). */
157 struct ipa_node_params
159 /* Information about individual formal parameters that are gathered when
160 summaries are generated. */
161 VEC (ipa_param_descriptor_t, heap) *descriptors;
162 /* Pointer to an array of structures describing individual formal
163 parameters. */
164 struct ipcp_lattice *lattices;
165 /* Only for versioned nodes this field would not be NULL,
166 it points to the node that IPA cp cloned from. */
167 struct cgraph_node *ipcp_orig_node;
168 /* If this node is an ipa-cp clone, these are the known values that describe
169 what it has been specialized for. */
170 VEC (tree, heap) *known_vals;
171 /* Whether this function is called with variable number of actual
172 arguments. */
173 unsigned called_with_var_arguments : 1;
174 /* Set when it is possible to create specialized versions of this node. */
175 unsigned node_versionable : 1;
176 /* Whether the param uses analysis has already been performed. */
177 unsigned uses_analysis_done : 1;
178 /* Whether the function is enqueued in ipa-cp propagation stack. */
179 unsigned node_enqueued : 1;
180 /* Whether we should create a specialized version based on values that are
181 known to be constant in all contexts. */
182 unsigned clone_for_all_contexts : 1;
183 /* Node has been completely replaced by clones and will be removed after
184 ipa-cp is finished. */
185 unsigned node_dead : 1;
188 /* ipa_node_params access functions. Please use these to access fields that
189 are or will be shared among various passes. */
191 /* Return the number of formal parameters. */
193 static inline int
194 ipa_get_param_count (struct ipa_node_params *info)
196 return VEC_length (ipa_param_descriptor_t, info->descriptors);
199 /* Return the declaration of Ith formal parameter of the function corresponding
200 to INFO. Note there is no setter function as this array is built just once
201 using ipa_initialize_node_params. */
203 static inline tree
204 ipa_get_param (struct ipa_node_params *info, int i)
206 return VEC_index (ipa_param_descriptor_t, info->descriptors, i)->decl;
209 /* Set the used flag corresponding to the Ith formal parameter of the function
210 associated with INFO to VAL. */
212 static inline void
213 ipa_set_param_used (struct ipa_node_params *info, int i, bool val)
215 VEC_index (ipa_param_descriptor_t, info->descriptors, i)->used = val;
218 /* Return the used flag corresponding to the Ith formal parameter of the
219 function associated with INFO. */
221 static inline bool
222 ipa_is_param_used (struct ipa_node_params *info, int i)
224 return VEC_index (ipa_param_descriptor_t, info->descriptors, i)->used;
227 /* Flag this node as having callers with variable number of arguments. */
229 static inline void
230 ipa_set_called_with_variable_arg (struct ipa_node_params *info)
232 info->called_with_var_arguments = 1;
235 /* Have we detected this node was called with variable number of arguments? */
237 static inline bool
238 ipa_is_called_with_var_arguments (struct ipa_node_params *info)
240 return info->called_with_var_arguments;
243 /* ipa_edge_args stores information related to a callsite and particularly its
244 arguments. It can be accessed by the IPA_EDGE_REF macro. */
245 typedef struct GTY(()) ipa_edge_args
247 /* Number of actual arguments in this callsite. When set to 0,
248 this callsite's parameters would not be analyzed by the different
249 stages of IPA CP. */
250 int argument_count;
251 /* Array of the callsite's jump function of each parameter. */
252 struct ipa_jump_func GTY ((length ("%h.argument_count"))) *jump_functions;
253 } ipa_edge_args_t;
255 /* ipa_edge_args access functions. Please use these to access fields that
256 are or will be shared among various passes. */
258 /* Set the number of actual arguments. */
260 static inline void
261 ipa_set_cs_argument_count (struct ipa_edge_args *args, int count)
263 args->argument_count = count;
266 /* Return the number of actual arguments. */
268 static inline int
269 ipa_get_cs_argument_count (struct ipa_edge_args *args)
271 return args->argument_count;
274 /* Returns a pointer to the jump function for the ith argument. Please note
275 there is no setter function as jump functions are all set up in
276 ipa_compute_jump_functions. */
278 static inline struct ipa_jump_func *
279 ipa_get_ith_jump_func (struct ipa_edge_args *args, int i)
281 gcc_assert (i >= 0 && i <= args->argument_count);
282 return &args->jump_functions[i];
285 /* Vectors need to have typedefs of structures. */
286 typedef struct ipa_node_params ipa_node_params_t;
288 /* Types of vectors holding the infos. */
289 DEF_VEC_O (ipa_node_params_t);
290 DEF_VEC_ALLOC_O (ipa_node_params_t, heap);
291 DEF_VEC_O (ipa_edge_args_t);
292 DEF_VEC_ALLOC_O (ipa_edge_args_t, gc);
294 /* Vector where the parameter infos are actually stored. */
295 extern VEC (ipa_node_params_t, heap) *ipa_node_params_vector;
296 /* Vector where the parameter infos are actually stored. */
297 extern GTY(()) VEC (ipa_edge_args_t, gc) *ipa_edge_args_vector;
299 /* Return the associated parameter/argument info corresponding to the given
300 node/edge. */
301 #define IPA_NODE_REF(NODE) (VEC_index (ipa_node_params_t, \
302 ipa_node_params_vector, (NODE)->uid))
303 #define IPA_EDGE_REF(EDGE) (VEC_index (ipa_edge_args_t, \
304 ipa_edge_args_vector, (EDGE)->uid))
305 /* This macro checks validity of index returned by
306 ipa_get_param_decl_index function. */
307 #define IS_VALID_JUMP_FUNC_INDEX(I) ((I) != -1)
309 /* Creating and freeing ipa_node_params and ipa_edge_args. */
310 void ipa_create_all_node_params (void);
311 void ipa_create_all_edge_args (void);
312 void ipa_free_edge_args_substructures (struct ipa_edge_args *);
313 void ipa_free_node_params_substructures (struct ipa_node_params *);
314 void ipa_free_all_node_params (void);
315 void ipa_free_all_edge_args (void);
316 void ipa_create_all_structures_for_iinln (void);
317 void ipa_free_all_structures_after_ipa_cp (void);
318 void ipa_free_all_structures_after_iinln (void);
319 void ipa_register_cgraph_hooks (void);
321 /* This function ensures the array of node param infos is big enough to
322 accommodate a structure for all nodes and reallocates it if not. */
324 static inline void
325 ipa_check_create_node_params (void)
327 if (!ipa_node_params_vector)
328 ipa_node_params_vector = VEC_alloc (ipa_node_params_t, heap,
329 cgraph_max_uid);
331 if (VEC_length (ipa_node_params_t, ipa_node_params_vector)
332 <= (unsigned) cgraph_max_uid)
333 VEC_safe_grow_cleared (ipa_node_params_t, heap,
334 ipa_node_params_vector, cgraph_max_uid + 1);
337 /* This function ensures the array of edge arguments infos is big enough to
338 accommodate a structure for all edges and reallocates it if not. */
340 static inline void
341 ipa_check_create_edge_args (void)
343 if (!ipa_edge_args_vector)
344 ipa_edge_args_vector = VEC_alloc (ipa_edge_args_t, gc,
345 cgraph_edge_max_uid);
347 if (VEC_length (ipa_edge_args_t, ipa_edge_args_vector)
348 <= (unsigned) cgraph_edge_max_uid)
349 VEC_safe_grow_cleared (ipa_edge_args_t, gc, ipa_edge_args_vector,
350 cgraph_edge_max_uid + 1);
353 /* Returns true if the array of edge infos is large enough to accommodate an
354 info for EDGE. The main purpose of this function is that debug dumping
355 function can check info availability without causing reallocations. */
357 static inline bool
358 ipa_edge_args_info_available_for_edge_p (struct cgraph_edge *edge)
360 return ((unsigned) edge->uid < VEC_length (ipa_edge_args_t,
361 ipa_edge_args_vector));
364 /* Function formal parameters related computations. */
365 void ipa_initialize_node_params (struct cgraph_node *node);
366 bool ipa_propagate_indirect_call_infos (struct cgraph_edge *cs,
367 VEC (cgraph_edge_p, heap) **new_edges);
369 /* Indirect edge and binfo processing. */
370 struct cgraph_edge *ipa_make_edge_direct_to_target (struct cgraph_edge *, tree,
371 tree);
373 /* Functions related to both. */
374 void ipa_analyze_node (struct cgraph_node *);
376 /* Debugging interface. */
377 void ipa_print_node_params (FILE *, struct cgraph_node *node);
378 void ipa_print_all_params (FILE *);
379 void ipa_print_node_jump_functions (FILE *f, struct cgraph_node *node);
380 void ipa_print_all_jump_functions (FILE * f);
381 void ipcp_verify_propagated_values (void);
383 extern alloc_pool ipcp_values_pool;
384 extern alloc_pool ipcp_sources_pool;
386 /* Structure to describe transformations of formal parameters and actual
387 arguments. Each instance describes one new parameter and they are meant to
388 be stored in a vector. Additionally, most users will probably want to store
389 adjustments about parameters that are being removed altogether so that SSA
390 names belonging to them can be replaced by SSA names of an artificial
391 variable. */
392 struct ipa_parm_adjustment
394 /* The original PARM_DECL itself, helpful for processing of the body of the
395 function itself. Intended for traversing function bodies.
396 ipa_modify_formal_parameters, ipa_modify_call_arguments and
397 ipa_combine_adjustments ignore this and use base_index.
398 ipa_modify_formal_parameters actually sets this. */
399 tree base;
401 /* Type of the new parameter. However, if by_ref is true, the real type will
402 be a pointer to this type. */
403 tree type;
405 /* Alias refrerence type to be used in MEM_REFs when adjusting caller
406 arguments. */
407 tree alias_ptr_type;
409 /* The new declaration when creating/replacing a parameter. Created by
410 ipa_modify_formal_parameters, useful for functions modifying the body
411 accordingly. */
412 tree reduction;
414 /* New declaration of a substitute variable that we may use to replace all
415 non-default-def ssa names when a parm decl is going away. */
416 tree new_ssa_base;
418 /* If non-NULL and the original parameter is to be removed (copy_param below
419 is NULL), this is going to be its nonlocalized vars value. */
420 tree nonlocal_value;
422 /* Offset into the original parameter (for the cases when the new parameter
423 is a component of an original one). */
424 HOST_WIDE_INT offset;
426 /* Zero based index of the original parameter this one is based on. (ATM
427 there is no way to insert a new parameter out of the blue because there is
428 no need but if it arises the code can be easily exteded to do so.) */
429 int base_index;
431 /* This new parameter is an unmodified parameter at index base_index. */
432 unsigned copy_param : 1;
434 /* This adjustment describes a parameter that is about to be removed
435 completely. Most users will probably need to book keep those so that they
436 don't leave behinfd any non default def ssa names belonging to them. */
437 unsigned remove_param : 1;
439 /* The parameter is to be passed by reference. */
440 unsigned by_ref : 1;
443 typedef struct ipa_parm_adjustment ipa_parm_adjustment_t;
444 DEF_VEC_O (ipa_parm_adjustment_t);
445 DEF_VEC_ALLOC_O (ipa_parm_adjustment_t, heap);
447 typedef VEC (ipa_parm_adjustment_t, heap) *ipa_parm_adjustment_vec;
449 VEC(tree, heap) *ipa_get_vector_of_formal_parms (tree fndecl);
450 void ipa_modify_formal_parameters (tree fndecl, ipa_parm_adjustment_vec,
451 const char *);
452 void ipa_modify_call_arguments (struct cgraph_edge *, gimple,
453 ipa_parm_adjustment_vec);
454 ipa_parm_adjustment_vec ipa_combine_adjustments (ipa_parm_adjustment_vec,
455 ipa_parm_adjustment_vec);
456 void ipa_dump_param_adjustments (FILE *, ipa_parm_adjustment_vec, tree);
458 void ipa_prop_write_jump_functions (cgraph_node_set set);
459 void ipa_prop_read_jump_functions (void);
460 void ipa_update_after_lto_read (void);
461 int ipa_get_param_decl_index (struct ipa_node_params *, tree);
462 tree ipa_cst_from_jfunc (struct ipa_node_params *info,
463 struct ipa_jump_func *jfunc);
466 /* From tree-sra.c: */
467 tree build_ref_for_offset (location_t, tree, HOST_WIDE_INT, tree,
468 gimple_stmt_iterator *, bool);
470 #endif /* IPA_PROP_H */