1 /* Interprocedural analyses.
2 Copyright (C) 2005, 2007, 2008 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
27 /* The following definitions and interfaces are used by
28 interprocedural analyses. */
30 /* A jump function for a callsite represents the values passed as actual
31 arguments of the callsite. There are three main types of values :
32 Formal - the caller's formal parameter is passed as an actual argument.
33 Constant - a constant is passed as an actual argument.
34 Unknown - neither of the above.
35 Integer and real constants are represented as IPA_CONST.
36 Finally, IPA_CONST_MEMBER_PTR stands for C++ member pointers constants. */
39 IPA_UNKNOWN = 0, /* newly allocated and zeroed jump functions default */
45 /* All formal parameters in the program have a lattice associated with it
46 computed by the interprocedural stage of IPCP.
47 There are three main values of the lattice:
49 IPA_BOTTOM - non constant,
50 IPA_CONST_VALUE - simple scalar constant,
51 Cval of formal f will have a constant value if all callsites to this
52 function have the same constant value passed to f.
53 Integer and real constants are represented as IPA_CONST. */
61 /* Structure holding a C++ member pointer constant. Holds a pointer to the
62 method and delta offset. */
63 struct ipa_member_ptr_cst
69 /* Represents a value of a jump function. formal_id is used only in jump
70 function context and represents pass-through parameter (the formal parameter
71 of the caller is passed as argument). constant represents the actual
72 constant in constant jump functions and member_cst holds constant c++ member
76 unsigned int formal_id;
78 struct ipa_member_ptr_cst member_cst;
81 /* A jump function for a callsite represents the values passed as actual
82 arguments of the callsite. See enum jump_func_type for the various
83 types of jump functions supported. */
86 enum jump_func_type type;
87 union jump_func_value value;
90 /* All formal parameters in the program have a cval computed by
91 the interprocedural stage of IPCP. See enum ipa_lattice_type for
92 the various types of lattices supported */
95 enum ipa_lattice_type type;
99 /* Represent which DECL tree (or reference to such tree)
100 will be replaced by another tree while versioning. */
101 struct ipa_replace_map
103 /* The tree that will be replaced. */
105 /* The new (replacing) tree. */
107 /* True when a substitution should be done, false otherwise. */
109 /* True when we replace a reference to old_tree. */
113 /* Each instance of the following structure describes a statement that calls a
114 function parameter. Those referring to statements within the same function
115 are linked in a list. */
116 struct ipa_param_call_note
118 /* Linked list's next */
119 struct ipa_param_call_note *next;
120 /* Statement that contains the call to the parameter above. */
122 /* Index of the parameter that is called. */
123 unsigned int formal_id;
124 /* Expected number of executions: calculated in profile.c. */
126 /* Expected frequency of executions within the function. see cgraph_edge in
127 cgraph.h for more on this. */
129 /* Depth of loop nest, 1 means no loop nest. */
131 /* Set when we have already found the target to be a compile time constant
132 and turned this into an edge or when the note was found unusable for some
137 /* Structure describing a single formal parameter. */
138 struct ipa_param_descriptor
140 /* IPA-CP lattice. */
141 struct ipcp_lattice ipcp_lattice;
142 /* PARAM_DECL of this parameter. */
144 /* Whether the value parameter has been modified within the function. */
145 unsigned modified : 1;
146 /* Whether the parameter has been used as a call destination. */
150 /* ipa_node_params stores information related to formal parameters of functions
151 and some other information for interprocedural passes that operate on
152 parameters (such as ipa-cp). */
153 struct ipa_node_params
155 /* Number of formal parameters of this function. When set to 0,
156 this function's parameters would not be analyzed by the different
159 /* Pointer to an array of structures describing individual formal
161 struct ipa_param_descriptor *params;
162 /* List of structures enumerating calls to a formal parameter. */
163 struct ipa_param_call_note *param_calls;
164 /* Only for versioned nodes this field would not be NULL,
165 it points to the node that IPA cp cloned from. */
166 struct cgraph_node *ipcp_orig_node;
167 /* Meaningful only for original functions. Expresses the
168 ratio between the direct calls and sum of all invocations of
169 this function (given by profiling info). It is used to calculate
170 the profiling information of the original function and the versioned
172 gcov_type count_scale;
174 /* Whether this function is called with variable number of actual
176 unsigned called_with_var_arguments : 1;
177 /* Whether the modification analysis has already been performed. */
178 unsigned modification_analysis_done : 1;
179 /* Whether the param uses analysis has already been performed. */
180 unsigned uses_analysis_done : 1;
183 /* ipa_node_params access functions. Please use these to access fields that
184 are or will be shared among various passes. */
186 /* Set the number of formal parameters. */
188 ipa_set_param_count (struct ipa_node_params *info, int count)
190 info->param_count = count;
193 /* Return the number of formal parameters. */
195 ipa_get_param_count (struct ipa_node_params *info)
197 return info->param_count;
200 /* Return the declaration of Ith formal parameter of the function corresponding
201 to INFO. Note there is no setter function as this array is built just once
202 using ipa_initialize_node_params. */
204 ipa_get_param (struct ipa_node_params *info, int i)
206 return info->params[i].decl;
209 /* Return the modification flag corresponding to the Ith formal parameter of
210 the function associated with INFO. Note that there is no setter method as
211 the goal is to set all flags when building the array in
212 ipa_detect_param_modifications. */
214 ipa_is_param_modified (struct ipa_node_params *info, int i)
216 return info->params[i].modified;
219 /* Return the called flag corresponding to the Ith formal parameter of the
220 function associated with INFO. Note that there is no setter method as the
221 goal is to set all flags when building the array in
222 ipa_detect_called_params. */
224 ipa_is_param_called (struct ipa_node_params *info, int i)
226 return info->params[i].called;
229 /* Flag this node as having callers with variable number of arguments. */
231 ipa_set_called_with_variable_arg (struct ipa_node_params *info)
233 info->called_with_var_arguments = 1;
236 /* Have we detected this node was called with variable number of arguments? */
238 ipa_is_called_with_var_arguments (struct ipa_node_params *info)
240 return info->called_with_var_arguments;
245 /* ipa_edge_args stores information related to a callsite and particularly
246 its arguments. It is pointed to by a field in the
247 callsite's corresponding cgraph_edge. */
250 /* Number of actual arguments in this callsite. When set to 0,
251 this callsite's parameters would not be analyzed by the different
254 /* Array of the callsite's jump function of each parameter. */
255 struct ipa_jump_func *jump_functions;
258 /* ipa_edge_args access functions. Please use these to access fields that
259 are or will be shared among various passes. */
261 /* Set the number of actual arguments. */
263 ipa_set_cs_argument_count (struct ipa_edge_args *args, int count)
265 args->argument_count = count;
268 /* Return the number of actual arguments. */
270 ipa_get_cs_argument_count (struct ipa_edge_args *args)
272 return args->argument_count;
275 /* Returns a pointer to the jump function for the ith argument. Please note
276 there is no setter function as jump functions are all set up in
277 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 return &args->jump_functions[i];
284 /* Vectors need to have typedefs of structures. */
285 typedef struct ipa_node_params ipa_node_params_t;
286 typedef struct ipa_edge_args ipa_edge_args_t;
288 /* Types of vectors hodling 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, heap);
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 VEC (ipa_edge_args_t, heap) *ipa_edge_args_vector;
299 /* Return the associated parameter/argument info corresponding to the given
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 free_all_ipa_structures_after_ipa_cp (void);
317 void free_all_ipa_structures_after_iinln (void);
318 void ipa_register_cgraph_hooks (void);
320 /* This function ensures the array of node param infos is big enough to
321 accomdate a structure for all nodes and realloacates it if not. */
323 ipa_check_create_node_params (void)
325 if (!ipa_node_params_vector)
326 ipa_node_params_vector = VEC_alloc (ipa_node_params_t, heap,
329 if (VEC_length (ipa_node_params_t, ipa_node_params_vector)
330 <= (unsigned) cgraph_max_uid)
331 VEC_safe_grow_cleared (ipa_node_params_t, heap,
332 ipa_node_params_vector, cgraph_max_uid + 1);
335 /* This function ensures the array of adge arguments infos is big enough to
336 accomdate a structure for all edges and realloacates it if not. */
338 ipa_check_create_edge_args (void)
340 if (!ipa_edge_args_vector)
341 ipa_edge_args_vector = VEC_alloc (ipa_edge_args_t, heap,
342 cgraph_edge_max_uid);
344 if (VEC_length (ipa_edge_args_t, ipa_edge_args_vector)
345 <= (unsigned) cgraph_edge_max_uid)
346 VEC_safe_grow_cleared (ipa_edge_args_t, heap, ipa_edge_args_vector,
347 cgraph_edge_max_uid + 1);
350 /* Returns true if the array of edge infos is large enough to accomodate an
351 info for EDGE. The main purpose of this function is that debug dumping
352 function can check info availability without causing reallocations. */
354 ipa_edge_args_info_available_for_edge_p (struct cgraph_edge *edge)
356 return ((unsigned) edge->uid < VEC_length (ipa_edge_args_t,
357 ipa_edge_args_vector));
360 /* A function list element. It is used to create a temporary worklist used in
361 the propagation stage of IPCP. (can be used for more IPA optimizations) */
364 struct cgraph_node *node;
365 struct ipa_func_list *next;
368 /* ipa_func_list interface. */
369 struct ipa_func_list *ipa_init_func_list (void);
370 void ipa_push_func_to_list (struct ipa_func_list **, struct cgraph_node *);
371 struct cgraph_node *ipa_pop_func_from_list (struct ipa_func_list **);
373 /* Callsite related calculations. */
374 void ipa_compute_jump_functions (struct cgraph_edge *);
375 void ipa_count_arguments (struct cgraph_edge *);
377 /* Function formal parameters related computations. */
378 void ipa_initialize_node_params (struct cgraph_node *node);
379 void ipa_detect_param_modifications (struct cgraph_node *);
380 void ipa_analyze_params_uses (struct cgraph_node *);
381 bool ipa_propagate_indirect_call_infos (struct cgraph_edge *cs,
382 VEC (cgraph_edge_p, heap) **new_edges);
384 /* Debugging interface. */
385 void ipa_print_node_params (FILE *, struct cgraph_node *node);
386 void ipa_print_all_params (FILE *);
387 void ipa_print_node_jump_functions (FILE *f, struct cgraph_node *node);
388 void ipa_print_all_jump_functions (FILE * f);
390 #endif /* IPA_PROP_H */