nsz Git - libfirm/blob - ir/be/beprofile.c

   1 /*
   2  * Copyright (C) 1995-2007 University of Karlsruhe.  All right reserved.
   3  *
   4  * This file is part of libFirm.
   5  *
   6  * This file may be distributed and/or modified under the terms of the
   7  * GNU General Public License version 2 as published by the Free Software
   8  * Foundation and appearing in the file LICENSE.GPL included in the
   9  * packaging of this file.
  10  *
  11  * Licensees holding valid libFirm Professional Edition licenses may use
  12  * this file in accordance with the libFirm Commercial License.
  13  * Agreement provided with the Software.
  14  *
  15  * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
  16  * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  17  * PURPOSE.
  18  */
  19
  20 /**
  21  * @file
  22  * @brief       Code instrumentation and execution count profiling.
  23  * @author      Adam M. Szalkowski
  24  * @date        06.04.2006
  25  * @version     $Id$
  26  */
  27 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #include <math.h>
  32
  33 #include "hashptr.h"
  34 #include "debug.h"
  35 #include "obst.h"
  36 #include "set.h"
  37 #include "list.h"
  38 #include "pmap.h"
  39
  40 #include "irprintf.h"
  41 #include "irgwalk.h"
  42 #include "irdump_t.h"
  43 #include "irnode_t.h"
  44 #include "ircons_t.h"
  45 #include "irloop_t.h"
  46 #include "iredges.h"
  47 #include "execfreq.h"
  48 #include "irvrfy.h"
  49 #include "typerep.h"
  50
  51 #include "be_t.h"
  52 #include "belive_t.h"
  53 #include "besched_t.h"
  54 #include "beirgmod.h"
  55 #include "bearch_t.h"
  56 #include "beabi.h"
  57 #include "benode_t.h"
  58 #include "beutil.h"
  59 #include "ircons.h"
  60 #include "irhooks.h"
  61 #include "iredges.h"
  62
  63 #include "bechordal_t.h"
  64
  65 #include "beprofile.h"
  66
  67 /** An entry in the id-to-location map */
  68 typedef struct loc_entry {
  69         ir_entity    *fname;   /**< the entity holding the file name */
  70         unsigned int lineno;   /**< line number */
  71 } loc_entry;
  72
  73 typedef struct _block_id_walker_data_t {
  74         tarval         **array;    /**< the entity the holds the block counts */
  75         unsigned int   id;         /**< current block id number */
  76         ir_node        *symconst;  /**< the SymConst representing array */
  77         pmap           *fname_map; /**< set containing all found filenames */
  78         loc_entry      *locs;      /**< locations */
  79         ir_type        *tp_char;   /**< the character type */
  80         unsigned       flags;      /**< profile flags */
  81 } block_id_walker_data_t;
  82
  83 typedef struct _execcount_t {
  84         unsigned int block;
  85         unsigned int count;
  86 } execcount_t;
  87
  88 static int
  89 cmp_execcount(const void * a, const void * b, size_t size)
  90 {
  91         (void) size;
  92         return ((execcount_t*)a)->block != ((execcount_t*)b)->block;
  93 }
  94
  95 static void
  96 block_counter(ir_node * bb, void * data)
  97 {
  98         unsigned int  *count = data;
  99         (void) bb;
 100         *count = *count + 1;
 101 }
 102
 103 static unsigned int
 104 count_blocks(ir_graph * irg)
 105 {
 106         unsigned int count = 0;
 107
 108         irg_block_walk_graph(irg, block_counter, NULL, &count);
 109         return count;
 110 }
 111
 112 /* keep the execcounts here because they are only read once per compiler run */
 113 static set * profile = NULL;
 114 static hook_entry_t hook;
 115
 116 /**
 117  * Instrument a block with code needed for profiling
 118  */
 119 static void
 120 instrument_block(ir_node * bb, ir_node * address, unsigned int id)
 121 {
 122         ir_graph *irg = get_irn_irg(bb);
 123         ir_node  *start_block = get_irg_start_block(irg);
 124         ir_node  *load, *store, *offset, *add, *projm, *proji, *unknown;
 125         ir_node  *cnst;
 126
 127         /**
 128          * We can't instrument the start and end block as there are no real
 129          * instructions in these blocks
 130          */
 131         if(bb == start_block || bb == get_irg_end_block(irg))
 132                 return;
 133
 134         unknown = new_r_Unknown(irg, mode_M);
 135         cnst    = new_r_Const_long(irg, start_block, mode_Iu, get_mode_size_bytes(mode_Iu) * id);
 136         offset  = new_r_Add(irg, bb, address, cnst, mode_P);
 137         load    = new_r_Load(irg, bb, unknown, offset, mode_Iu);
 138         projm   = new_r_Proj(irg, bb, load, mode_M, pn_Load_M);
 139         proji   = new_r_Proj(irg, bb, load, mode_Iu, pn_Load_res);
 140         cnst    = new_r_Const_long(irg, start_block, mode_Iu, 1);
 141         add     = new_r_Add(irg, bb, proji, cnst, mode_Iu);
 142         store   = new_r_Store(irg, bb, projm, offset, add);
 143         projm   = new_r_Proj(irg, bb, store, mode_M, pn_Store_M);
 144         set_irn_link(bb, projm);
 145         set_irn_link(projm, load);
 146 }
 147
 148 typedef struct fix_env {
 149         ir_node *start_block;
 150         ir_node *end_block;
 151 } fix_env;
 152
 153 /**
 154  * SSA Construction for instrumentation code memory
 155  */
 156 static void
 157 fix_ssa(ir_node * bb, void * data)
 158 {
 159         fix_env *env = data;
 160         ir_node *mem;
 161         int     arity = get_Block_n_cfgpreds(bb);
 162
 163         /* start and end block are not instrumented, skip! */
 164         if (bb == env->start_block || bb == env->end_block)
 165                 return;
 166
 167         if (arity == 1) {
 168                 mem = get_irn_link(get_Block_cfgpred_block(bb, 0));
 169         } else {
 170                 int n;
 171                 ir_node **ins;
 172                 ir_graph *irg = current_ir_graph;
 173
 174                 NEW_ARR_A(ir_node*, ins, arity);
 175                 for (n = arity - 1; n >= 0; --n) {
 176                         ins[n] = get_irn_link(get_Block_cfgpred_block(bb, n));
 177                 }
 178                 mem = new_r_Phi(irg, bb, arity, ins, mode_M);
 179         }
 180         set_Load_mem(get_irn_link(get_irn_link(bb)), mem);
 181 }
 182
 183
 184 /**
 185  * Generates a new irg which calls the initializer
 186  *
 187  * Pseudocode:
 188  *       void __firmprof_initializer(void) { __init_firmprof(ent_filename, bblock_id, bblock_counts, n_blocks); }
 189  */
 190 static ir_graph *
 191 gen_initializer_irg(ir_entity * ent_filename, ir_entity * bblock_id, ir_entity * bblock_counts, int n_blocks)
 192 {
 193         ir_node *start_block;
 194
 195         ir_node   *ins[4];
 196         ident     *name = new_id_from_str("__firmprof_initializer");
 197         ir_entity *ent  = new_entity(get_glob_type(), name, new_type_method(name, 0, 0));
 198         ir_node   *ret, *call, *symconst;
 199         symconst_symbol sym;
 200
 201         ident     *init_name = new_id_from_str("__init_firmprof");
 202         ir_type   *init_type = new_type_method(init_name, 4, 0);
 203         ir_type   *uint, *uintptr, *string;
 204         ir_entity *init_ent;
 205         ir_graph  *irg;
 206         ir_node   *bb;
 207         ir_type   *empty_frame_type;
 208
 209         set_entity_ld_ident(ent, name);
 210
 211         uint    = new_type_primitive(new_id_from_str("__uint"), mode_Iu);
 212         uintptr = new_type_pointer(new_id_from_str("__uintptr"), uint, mode_P);
 213         string  = new_type_pointer(new_id_from_str("__charptr"), new_type_primitive(new_id_from_str("__char"), mode_Bs), mode_P);
 214
 215         set_method_param_type(init_type, 0, string);
 216         set_method_param_type(init_type, 1, uintptr);
 217         set_method_param_type(init_type, 2, uintptr);
 218         set_method_param_type(init_type, 3, uint);
 219         init_ent = new_entity(get_glob_type(), init_name, init_type);
 220         set_entity_ld_ident(init_ent, init_name);
 221
 222         irg = new_ir_graph(ent, 0);
 223         empty_frame_type = get_irg_frame_type(irg);
 224         set_type_size_bytes(empty_frame_type, 0);
 225
 226         bb = get_cur_block();
 227
 228         start_block = get_irg_start_block(irg);
 229
 230         sym.entity_p = init_ent;
 231         symconst     = new_r_SymConst(irg, start_block, sym, symconst_addr_ent);
 232
 233         sym.entity_p = ent_filename;
 234         ins[0] = new_r_SymConst(irg, start_block, sym, symconst_addr_ent);
 235         sym.entity_p = bblock_id;
 236         ins[1] = new_r_SymConst(irg, start_block, sym, symconst_addr_ent);
 237         sym.entity_p = bblock_counts;
 238         ins[2] = new_r_SymConst(irg, start_block, sym, symconst_addr_ent);
 239         ins[3] = new_r_Const_long(irg, start_block, mode_Iu, n_blocks);
 240
 241         call = new_r_Call(irg, bb, get_irg_initial_mem(irg), symconst, 4, ins, init_type);
 242         ret = new_r_Return(irg, bb, new_r_Proj(irg, bb, call, mode_M, pn_Call_M_regular), 0, NULL);
 243         mature_immBlock(bb);
 244
 245         add_immBlock_pred(get_irg_end_block(irg), ret);
 246         mature_immBlock(get_irg_end_block(irg));
 247
 248         irg_finalize_cons(irg);
 249
 250         return irg;
 251 }
 252
 253 /**
 254  * Create the location data for the given debug info.
 255  */
 256 static void create_location_data(dbg_info *dbg, block_id_walker_data_t *wd)
 257 {
 258         unsigned lineno;
 259         const char *fname = be_retrieve_dbg_info(dbg, &lineno);
 260
 261         if (fname) {
 262                 pmap_entry *entry = pmap_find(wd->fname_map, (void *)fname);
 263                 ir_entity  *ent;
 264
 265                 if (! entry) {
 266                         static unsigned nr = 0;
 267                         ident   *id;
 268                         char    buf[128];
 269                         ir_type *arr;
 270                         int     i, len = strlen(fname) + 1;
 271                         tarval  **tarval_string;
 272
 273                         snprintf(buf, sizeof(buf), "firm_name_arr.%d", nr);
 274                         arr = new_type_array(new_id_from_str(buf), 1, wd->tp_char);
 275                         set_array_bounds_int(arr, 0, 0, len);
 276
 277                         snprintf(buf, sizeof(buf), "__firm_name.%d", nr++);
 278                         id = new_id_from_str(buf);
 279                         ent = new_entity(get_glob_type(), id, arr);
 280                         set_entity_ld_ident(ent, id);
 281
 282                         pmap_insert(wd->fname_map, (void *)fname, ent);
 283
 284                         /* initialize file name string constant */
 285                         tarval_string = alloca(sizeof(*tarval_string) * (len));
 286                         for (i = 0; i < len; ++i) {
 287                                 tarval_string[i] = new_tarval_from_long(fname[i], mode_Bs);
 288                         }
 289                         set_entity_variability(ent, variability_constant);
 290                         set_array_entity_values(ent, tarval_string, len);
 291                 } else {
 292                         ent = entry->value;
 293                 }
 294                 wd->locs[wd->id].fname  = ent;
 295                 wd->locs[wd->id].lineno = lineno;
 296         } else {
 297                 wd->locs[wd->id].fname  = NULL;
 298                 wd->locs[wd->id].lineno = 0;
 299         }
 300 }
 301
 302 /**
 303  * Walker: assigns an ID to every block.
 304  * Builds the string table
 305  */
 306 static void
 307 block_id_walker(ir_node * bb, void * data)
 308 {
 309         block_id_walker_data_t *wd = data;
 310
 311         wd->array[wd->id] = new_tarval_from_long(get_irn_node_nr(bb), mode_Iu);
 312         instrument_block(bb, wd->symconst, wd->id);
 313
 314         if (wd->flags & profile_with_locations) {
 315                 dbg_info *dbg = get_irn_dbg_info(bb);
 316                 create_location_data(dbg, wd);
 317         }
 318         ++wd->id;
 319 }
 320
 321 #define IDENT(x)        new_id_from_chars(x, sizeof(x) - 1)
 322
 323 ir_graph *
 324 be_profile_instrument(const char *filename, unsigned flags)
 325 {
 326         int n, i;
 327         int n_blocks = 0;
 328         ir_entity *bblock_id;
 329         ir_entity *bblock_counts;
 330         ir_entity *ent_filename;
 331         ir_entity *ent_locations = NULL;
 332         ir_entity *loc_lineno = NULL;
 333         ir_entity *loc_name = NULL;
 334         ir_entity *ent;
 335         ir_type *array_type;
 336         ir_type *uint_type;
 337         ir_type *string_type;
 338         ir_type *character_type;
 339         ir_type *loc_type = NULL;
 340         ir_type *charptr_type;
 341         ir_type *gtp;
 342         tarval **tarval_array;
 343         tarval **tarval_string;
 344         tarval *tv;
 345         int filename_len = strlen(filename)+1;
 346         ident *cur_ident;
 347         int align_l, align_n, size;
 348         ir_graph *rem;
 349         block_id_walker_data_t  wd;
 350         symconst_symbol sym;
 351
 352         /* count the number of block first */
 353         for (n = get_irp_n_irgs() - 1; n >= 0; --n) {
 354                 ir_graph *irg = get_irp_irg(n);
 355
 356                 n_blocks += count_blocks(irg);
 357         }
 358
 359         /* create all the necessary types and entities. Note that the
 360            types must have a fixed layout, because we already running in the
 361            backend */
 362         uint_type      = new_type_primitive(IDENT("__uint"), mode_Iu);
 363         set_type_alignment_bytes(uint_type, get_type_size_bytes(uint_type));
 364         array_type     = new_type_array(IDENT("__block_info_array"), 1, uint_type);
 365         set_array_bounds_int(array_type, 0, 0, n_blocks);
 366
 367         character_type = new_type_primitive(IDENT("__char"), mode_Bs);
 368         string_type    = new_type_array(IDENT("__filename"), 1, character_type);
 369         set_array_bounds_int(string_type, 0, 0, filename_len);
 370
 371         gtp            = get_glob_type();
 372
 373         cur_ident      = IDENT("__FIRMPROF__BLOCK_IDS");
 374         bblock_id      = new_entity(gtp, cur_ident, array_type);
 375         set_entity_ld_ident(bblock_id, cur_ident);
 376         set_entity_variability(bblock_id, variability_initialized);
 377
 378         cur_ident      = IDENT("__FIRMPROF__BLOCK_COUNTS");
 379         bblock_counts  = new_entity(gtp, cur_ident, array_type);
 380         set_entity_ld_ident(bblock_counts, cur_ident);
 381         set_entity_variability(bblock_counts, variability_initialized);
 382
 383         cur_ident      = IDENT("__FIRMPROF__FILE_NAME");
 384         ent_filename   = new_entity(gtp, cur_ident, string_type);
 385         set_entity_ld_ident(ent_filename, cur_ident);
 386
 387         if (flags & profile_with_locations) {
 388                 loc_type       = new_type_struct(IDENT("__location"));
 389                 loc_lineno     = new_entity(loc_type, IDENT("lineno"), uint_type);
 390                 align_l        = get_type_alignment_bytes(uint_type);
 391                 size           = get_type_size_bytes(uint_type);
 392                 set_entity_offset(loc_lineno, 0);
 393
 394                 charptr_type   = new_type_pointer(IDENT("__charptr"), character_type, mode_P_data);
 395                 align_n        = get_type_size_bytes(charptr_type);
 396                 set_type_alignment_bytes(charptr_type, align_n);
 397                 loc_name       = new_entity(loc_type, IDENT("name"), charptr_type);
 398                 size           = (size + align_n - 1) & -align_n;
 399                 set_entity_offset(loc_name, size);
 400                 size          += align_n;
 401
 402                 if (align_n > align_l)
 403                         align_l = align_n;
 404                 size = (size + align_l - 1) & -align_l;
 405                 set_type_size_bytes(loc_type, size);
 406                 set_type_state(loc_type, layout_fixed);
 407
 408                 loc_type = new_type_array(IDENT("__locarray"), 1, loc_type);
 409                 set_array_bounds_int(string_type, 0, 0, n_blocks);
 410
 411                 cur_ident      = IDENT("__FIRMPROF__LOCATIONS");
 412                 ent_locations   = new_entity(gtp, cur_ident, loc_type);
 413                 set_entity_ld_ident(ent_locations, cur_ident);
 414         }
 415
 416         /* initialize count array */
 417         NEW_ARR_A(tarval *, tarval_array, n_blocks);
 418         tv = get_tarval_null(mode_Iu);
 419         for (i = 0; i < n_blocks; ++i) {
 420                 tarval_array[i] = tv;
 421         }
 422         set_array_entity_values(bblock_counts, tarval_array, n_blocks);
 423
 424         /* initialize function name string constant */
 425         tarval_string = alloca(sizeof(*tarval_string) * (filename_len));
 426         for (i = 0; i < filename_len; ++i) {
 427                 tarval_string[i] = new_tarval_from_long(filename[i], mode_Bs);
 428         }
 429         set_entity_variability(ent_filename, variability_constant);
 430         set_array_entity_values(ent_filename, tarval_string, filename_len);
 431
 432         /* initialize block id array and instrument blocks */
 433         wd.array     = tarval_array;
 434         wd.id        = 0;
 435         wd.tp_char   = character_type;
 436         wd.flags     = flags;
 437         if (flags & profile_with_locations) {
 438                 wd.fname_map = pmap_create();
 439                 NEW_ARR_A(loc_entry, wd.locs, n_blocks);
 440         }
 441
 442         for (n = get_irp_n_irgs() - 1; n >= 0; --n) {
 443                 ir_graph      *irg = get_irp_irg(n);
 444                 int            i;
 445                 ir_node       *endbb = get_irg_end_block(irg);
 446                 fix_env       env;
 447
 448                 set_current_ir_graph(irg);
 449
 450                 /* generate a symbolic constant pointing to the count array */
 451                 sym.entity_p = bblock_counts;
 452                 wd.symconst  = new_r_SymConst(irg, get_irg_start_block(irg), sym, symconst_addr_ent);
 453
 454                 irg_block_walk_graph(irg, block_id_walker, NULL, &wd);
 455                 env.start_block = get_irg_start_block(irg);
 456                 env.end_block   = get_irg_end_block(irg);
 457                 set_irn_link(env.start_block, get_irg_no_mem(irg));
 458                 irg_block_walk_graph(irg, fix_ssa, NULL, &env);
 459                 for (i = get_Block_n_cfgpreds(endbb) - 1; i >= 0; --i) {
 460                         ir_node *node = skip_Proj(get_Block_cfgpred(endbb, i));
 461                         ir_node *bb   = get_Block_cfgpred_block(endbb, i);
 462                         ir_node *sync;
 463                         ir_node *ins[2];
 464
 465                         switch (get_irn_opcode(node)) {
 466                         case iro_Return:
 467                                 ins[0] = get_irn_link(bb);
 468                                 ins[1] = get_Return_mem(node);
 469                                 sync   = new_r_Sync(irg, bb, 2, ins);
 470                                 set_Return_mem(node, sync);
 471                                 break;
 472                         case iro_Raise:
 473                                 ins[0] = get_irn_link(bb);
 474                                 ins[1] = get_Raise_mem(node);
 475                                 sync   = new_r_Sync(irg, bb, 2, ins);
 476                                 set_Raise_mem(node, sync);
 477                                 break;
 478                         default:
 479                                 /* a fragile's op exception. There should be another path to End,
 480                                    so ignore it */
 481                                 assert(is_fragile_op(node) && "unexpected End control flow predecessor");
 482                         }
 483                 }
 484         }
 485         set_array_entity_values(bblock_id, tarval_array, n_blocks);
 486
 487         if (flags & profile_with_locations) {
 488                 /* build the initializer for the locations */
 489                 rem = current_ir_graph;
 490                 current_ir_graph = get_const_code_irg();
 491                 ent = get_array_element_entity(loc_type);
 492                 set_entity_variability(ent_locations, variability_constant);
 493                 for (i = 0; i < n_blocks; ++i) {
 494                         compound_graph_path *path;
 495                         tarval *tv;
 496                         ir_node *n;
 497
 498                         /* lineno */
 499                         path = new_compound_graph_path(loc_type, 2);
 500                         set_compound_graph_path_array_index(path, 0, i);
 501                         set_compound_graph_path_node(path, 0, ent);
 502                         set_compound_graph_path_node(path, 1, loc_lineno);
 503                         tv = new_tarval_from_long(wd.locs[i].lineno, mode_Iu);
 504                         add_compound_ent_value_w_path(ent_locations, new_Const(mode_Iu, tv), path);
 505
 506                         /* name */
 507                         path = new_compound_graph_path(loc_type, 2);
 508                         set_compound_graph_path_array_index(path, 0, i);
 509                         set_compound_graph_path_node(path, 0, ent);
 510                         set_compound_graph_path_node(path, 1, loc_name);
 511                         if (wd.locs[i].fname) {
 512                                 sym.entity_p = wd.locs[i].fname;
 513                                 n = new_SymConst(sym, symconst_addr_ent);
 514                         } else {
 515                                 n = new_Const(mode_P_data, get_mode_null(mode_P_data));
 516                         }
 517                         add_compound_ent_value_w_path(ent_locations, n, path);
 518                 }
 519                 pmap_destroy(wd.fname_map);
 520         }
 521         return gen_initializer_irg(ent_filename, bblock_id, bblock_counts, n_blocks);
 522 }
 523
 524 static void
 525 profile_node_info(void *ctx, FILE *f, const ir_node *irn)
 526 {
 527         (void) ctx;
 528         if(is_Block(irn)) {
 529                 fprintf(f, "profiled execution count: %u\n", be_profile_get_block_execcount(irn));
 530         }
 531 }
 532
 533 static void
 534 register_vcg_hook(void)
 535 {
 536         memset(&hook, 0, sizeof(hook));
 537         hook.hook._hook_node_info = profile_node_info;
 538         register_hook(hook_node_info, &hook);
 539 }
 540
 541 static void
 542 unregister_vcg_hook(void)
 543 {
 544         unregister_hook(hook_node_info, &hook);
 545 }
 546
 547 /**
 548  * Reads the corresponding profile info file if it exists and returns a
 549  * profile info struct
 550  */
 551 void
 552 be_profile_read(const char *filename)
 553 {
 554         FILE   *f;
 555         char    buf[8];
 556         size_t  ret;
 557
 558         f = fopen(filename, "r");
 559         if(f == NULL) {
 560                 return;
 561         }
 562         printf("found profile data '%s'.\n", filename);
 563
 564         /* check magic */
 565         ret = fread(buf, 8, 1, f);
 566         if(ret == 0 || strncmp(buf, "firmprof", 8) != 0) {
 567                 return;
 568         }
 569
 570         if(profile) be_profile_free();
 571         profile = new_set(cmp_execcount, 16);
 572
 573         do {
 574                 execcount_t  query;
 575                 ret = fread(&query, sizeof(unsigned int), 2, f);
 576
 577                 if(ret != 2) break;
 578
 579                 set_insert(profile, &query, sizeof(query), query.block);
 580         } while(1);
 581
 582         fclose(f);
 583         register_vcg_hook();
 584 }
 585
 586 /**
 587  * Frees the profile info
 588  */
 589 void
 590 be_profile_free(void)
 591 {
 592         if(profile) {
 593                 unregister_vcg_hook();
 594                 del_set(profile);
 595         }
 596 }
 597
 598 /**
 599  * Tells whether profile module has acquired data
 600  */
 601 int
 602 be_profile_has_data(void)
 603 {
 604         return (profile != NULL);
 605 }
 606
 607 /**
 608  * Get block execution count as determined be profiling
 609  */
 610 unsigned int
 611 be_profile_get_block_execcount(const ir_node *block)
 612 {
 613         execcount_t *ec, query;
 614
 615         if(!profile)
 616                 return 1;
 617
 618         query.block = get_irn_node_nr(block);
 619         ec = set_find(profile, &query, sizeof(query), get_irn_node_nr(block));
 620
 621         if(ec != NULL) {
 622                 return ec->count;
 623         } else {
 624                 ir_fprintf(stderr, "Warning: Profile contains no data for %+F\n",
 625                            block);
 626                 return 1;
 627         }
 628 }
 629
 630 typedef struct _intialize_execfreq_env_t {
 631         ir_graph *irg;
 632         ir_exec_freq *execfreqs;
 633         double freq_factor;
 634 } initialize_execfreq_env_t;
 635
 636 // minimal execution frequency (an execfreq of 0 confuses algos)
 637 static const double MIN_EXECFREQ = 0.00001;
 638
 639 static void initialize_execfreq(ir_node *block, void *data) {
 640         initialize_execfreq_env_t *env = data;
 641         double freq;
 642
 643         if(block == get_irg_start_block(env->irg)
 644            || block == get_irg_end_block(env->irg)) {
 645                 freq = 1.0;
 646         } else {
 647                 freq = be_profile_get_block_execcount(block);
 648                 freq *= env->freq_factor;
 649                 if(freq < MIN_EXECFREQ)
 650                         freq = MIN_EXECFREQ;
 651         }
 652
 653         set_execfreq(env->execfreqs, block, freq);
 654 }
 655
 656 ir_exec_freq *be_create_execfreqs_from_profile(ir_graph *irg)
 657 {
 658         ir_node *block2 = NULL;
 659         ir_node *start_block;
 660         const ir_edge_t *edge;
 661         initialize_execfreq_env_t env;
 662         unsigned count;
 663
 664         env.irg = irg;
 665         env.execfreqs = create_execfreq(irg);
 666
 667         // find the successor to the start block
 668         start_block = get_irg_start_block(irg);
 669         foreach_block_succ(start_block, edge) {
 670                 ir_node *succ = get_edge_src_irn(edge);
 671                 if(succ != start_block) {
 672                         block2 = succ;
 673                         break;
 674                 }
 675         }
 676         assert(block2 != NULL);
 677
 678         count = be_profile_get_block_execcount(block2);
 679         if(count == 0) {
 680                 // the function was never executed, so fallback to estimated freqs
 681                 free_execfreq(env.execfreqs);
 682
 683                 return compute_execfreq(irg, 10);
 684         }
 685
 686         env.freq_factor = 1.0 / count;
 687         irg_block_walk_graph(irg, initialize_execfreq, NULL, &env);
 688
 689         return env.execfreqs;
 690 }