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

   1 /** vim: set sw=4 ts=4:
   2  * @file   beprofile.c
   3  * @date   2006-04-06
   4  * @author Adam M. Szalkowski
   5  * @cvs-id $Id$
   6  *
   7  * Code instrumentation and execution count profiling
   8  *
   9  * Copyright (C) 2006 Universitaet Karlsruhe
  10  * Released under the GPL
  11  */
  12 #ifdef HAVE_CONFIG_H
  13 #include "config.h"
  14 #endif
  15
  16 #include <math.h>
  17
  18 #include "hashptr.h"
  19 #include "debug.h"
  20 #include "obst.h"
  21 #include "set.h"
  22 #include "list.h"
  23 #include "pmap.h"
  24
  25 #include "entity.h"
  26 #include "irprintf.h"
  27 #include "irgwalk.h"
  28 #include "irdump_t.h"
  29 #include "irnode_t.h"
  30 #include "ircons_t.h"
  31 #include "irloop_t.h"
  32 #include "iredges.h"
  33 #include "execfreq.h"
  34 #include "irvrfy.h"
  35 #include "type.h"
  36 #include "entity.h"
  37
  38 #include "be_t.h"
  39 #include "belive_t.h"
  40 #include "besched_t.h"
  41 #include "beirgmod.h"
  42 #include "bearch.h"
  43 #include "beabi.h"
  44 #include "benode_t.h"
  45 #include "beutil.h"
  46 #include "ircons.h"
  47 #include "irhooks.h"
  48 #include "iredges.h"
  49
  50 #include "bechordal_t.h"
  51
  52 #ifdef WITH_LIBCORE
  53 #include <libcore/lc_opts.h>
  54 #include <libcore/lc_opts_enum.h>
  55 #endif /* WITH_LIBCORE */
  56
  57 #include "beprofile.h"
  58
  59 /** An entry in the id-to-location map */
  60 typedef struct loc_entry {
  61         entity       *fname;   /**< the entity holding the file name */
  62         unsigned int lineno;   /**< line number */
  63 } loc_entry;
  64
  65 typedef struct _block_id_walker_data_t {
  66         tarval         **array;    /**< the entity the holds the block counts */
  67         unsigned int   id;         /**< current block id number */
  68         ir_node        *symconst;  /**< the SymConst representing array */
  69         pmap           *fname_map; /**< set containing all found filenames */
  70         loc_entry      *locs;      /**< locations */
  71         ir_type        *tp_char;   /**< the character type */
  72         unsigned       flags;      /**< profile flags */
  73 } block_id_walker_data_t;
  74
  75 typedef struct _execcount_t {
  76         unsigned int block;
  77         unsigned int count;
  78 } execcount_t;
  79
  80 static int
  81 cmp_execcount(const void * a, const void * b, size_t size)
  82 {
  83         return ((execcount_t*)a)->block != ((execcount_t*)b)->block;
  84 }
  85
  86 static void
  87 block_counter(ir_node * bb, void * data)
  88 {
  89         unsigned int  *count = data;
  90         *count = *count + 1;
  91 }
  92
  93 static unsigned int
  94 count_blocks(ir_graph * irg)
  95 {
  96         unsigned int count = 0;
  97
  98         irg_block_walk_graph(irg, block_counter, NULL, &count);
  99         return count;
 100 }
 101
 102 /* keep the execcounts here because they are only read once per compiler run */
 103 static set * profile = NULL;
 104 static hook_entry_t hook;
 105
 106 /**
 107  * Instrument a block with code needed for profiling
 108  */
 109 static void
 110 instrument_block(ir_node * bb, ir_node * address, unsigned int id)
 111 {
 112         ir_graph *irg = get_irn_irg(bb);
 113         ir_node  *start_block = get_irg_start_block(irg);
 114         ir_node  *load, *store, *offset, *add, *projm, *proji, *unknown;
 115         ir_node  *cnst;
 116
 117         /**
 118          * We can't instrument the start and end block as there are no real
 119          * instructions in these blocks
 120          */
 121         if(bb == start_block || bb == get_irg_end_block(irg))
 122                 return;
 123
 124         unknown = new_r_Unknown(irg, mode_M);
 125         cnst    = new_r_Const_long(irg, start_block, mode_Iu, get_mode_size_bytes(mode_Iu) * id);
 126         offset  = new_r_Add(irg, bb, address, cnst, mode_P);
 127         load    = new_r_Load(irg, bb, unknown, offset, mode_Iu);
 128         projm   = new_r_Proj(irg, bb, load, mode_M, pn_Load_M);
 129         proji   = new_r_Proj(irg, bb, load, mode_Iu, pn_Load_res);
 130         cnst    = new_r_Const_long(irg, start_block, mode_Iu, 1);
 131         add     = new_r_Add(irg, bb, proji, cnst, mode_Iu);
 132         store   = new_r_Store(irg, bb, projm, offset, add);
 133         projm   = new_r_Proj(irg, bb, store, mode_M, pn_Store_M);
 134         set_irn_link(bb, projm);
 135         set_irn_link(projm, load);
 136 }
 137
 138 typedef struct fix_env {
 139         ir_node *start_block;
 140         ir_node *end_block;
 141 } fix_env;
 142
 143 /**
 144  * SSA Construction for instrumentation code memory
 145  */
 146 static void
 147 fix_ssa(ir_node * bb, void * data)
 148 {
 149         fix_env *env = data;
 150         ir_node *mem;
 151         int     arity = get_Block_n_cfgpreds(bb);
 152
 153         /* start and end block are not instrumented, skip! */
 154         if (bb == env->start_block || bb == env->end_block)
 155                 return;
 156
 157         if (arity == 1) {
 158                 mem = get_irn_link(get_Block_cfgpred_block(bb, 0));
 159         } else {
 160                 int n;
 161                 ir_node **ins;
 162                 ir_graph *irg = current_ir_graph;
 163
 164                 NEW_ARR_A(ir_node*, ins, arity);
 165                 for (n = arity - 1; n >= 0; --n) {
 166                         ins[n] = get_irn_link(get_Block_cfgpred_block(bb, n));
 167                 }
 168                 mem = new_r_Phi(irg, bb, arity, ins, mode_M);
 169         }
 170         set_Load_mem(get_irn_link(get_irn_link(bb)), mem);
 171 }
 172
 173
 174 /**
 175  * Generates a new irg which calls the initializer
 176  *
 177  * Pseudocode:
 178  *       void __firmprof_initializer(void) { __init_firmprof(ent_filename, bblock_id, bblock_counts, n_blocks); }
 179  */
 180 static ir_graph *
 181 gen_initializer_irg(entity * ent_filename, entity * bblock_id, entity * bblock_counts, int n_blocks)
 182 {
 183         ir_node *start_block;
 184
 185         ir_node   *ins[4];
 186         ident     *name = new_id_from_str("__firmprof_initializer");
 187         entity    *ent  = new_entity(get_glob_type(), name, new_type_method(name, 0, 0));
 188         ir_node   *ret, *call, *symconst;
 189         symconst_symbol sym;
 190
 191         ident     *init_name = new_id_from_str("__init_firmprof");
 192         ir_type   *init_type = new_type_method(init_name, 4, 0);
 193         ir_type   *uint, *uintptr, *string;
 194         entity    *init_ent;
 195         ir_graph  *irg;
 196         ir_node   *bb;
 197         ir_type   *empty_frame_type;
 198
 199         set_entity_ld_ident(ent, name);
 200
 201         uint    = new_type_primitive(new_id_from_str("__uint"), mode_Iu);
 202         uintptr = new_type_pointer(new_id_from_str("__uintptr"), uint, mode_P);
 203         string  = new_type_pointer(new_id_from_str("__charptr"), new_type_primitive(new_id_from_str("__char"), mode_Bs), mode_P);
 204
 205         set_method_param_type(init_type, 0, string);
 206         set_method_param_type(init_type, 1, uintptr);
 207         set_method_param_type(init_type, 2, uintptr);
 208         set_method_param_type(init_type, 3, uint);
 209         init_ent = new_entity(get_glob_type(), init_name, init_type);
 210         set_entity_ld_ident(init_ent, init_name);
 211
 212         irg = new_ir_graph(ent, 0);
 213         empty_frame_type = get_irg_frame_type(irg);
 214         set_type_size_bytes(empty_frame_type, 0);
 215
 216         bb = get_cur_block();
 217
 218         start_block = get_irg_start_block(irg);
 219
 220         sym.entity_p = init_ent;
 221         symconst     = new_r_SymConst(irg, start_block, sym, symconst_addr_ent);
 222
 223         sym.entity_p = ent_filename;
 224         ins[0] = new_r_SymConst(irg, start_block, sym, symconst_addr_ent);
 225         sym.entity_p = bblock_id;
 226         ins[1] = new_r_SymConst(irg, start_block, sym, symconst_addr_ent);
 227         sym.entity_p = bblock_counts;
 228         ins[2] = new_r_SymConst(irg, start_block, sym, symconst_addr_ent);
 229         ins[3] = new_r_Const_long(irg, start_block, mode_Iu, n_blocks);
 230
 231         call = new_r_Call(irg, bb, get_irg_initial_mem(irg), symconst, 4, ins, init_type);
 232         ret = new_r_Return(irg, bb, new_r_Proj(irg, bb, call, mode_M, pn_Call_M_regular), 0, NULL);
 233         mature_immBlock(bb);
 234
 235         add_immBlock_pred(get_irg_end_block(irg), ret);
 236         mature_immBlock(get_irg_end_block(irg));
 237
 238         irg_finalize_cons(irg);
 239
 240         return irg;
 241 }
 242
 243 /**
 244  * Create the location data for the given debug info.
 245  */
 246 static void create_location_data(dbg_info *dbg, block_id_walker_data_t *wd)
 247 {
 248         unsigned lineno;
 249         const char *fname = be_retrieve_dbg_info(dbg, &lineno);
 250
 251         if (fname) {
 252                 pmap_entry *entry = pmap_find(wd->fname_map, (void *)fname);
 253                 entity     *ent;
 254
 255                 if (! entry) {
 256                         static unsigned nr = 0;
 257                         ident   *id;
 258                         char    buf[128];
 259                         ir_type *arr;
 260                         int     i, len = strlen(fname) + 1;
 261                         tarval  **tarval_string;
 262
 263                         snprintf(buf, sizeof(buf), "firm_name_arr.%d", nr);
 264                         arr = new_type_array(new_id_from_str(buf), 1, wd->tp_char);
 265                         set_array_bounds_int(arr, 0, 0, len);
 266
 267                         snprintf(buf, sizeof(buf), "__firm_name.%d", nr++);
 268                         id = new_id_from_str(buf);
 269                         ent = new_entity(get_glob_type(), id, arr);
 270                         set_entity_ld_ident(ent, id);
 271
 272                         pmap_insert(wd->fname_map, (void *)fname, ent);
 273
 274                         /* initialize file name string constant */
 275                         tarval_string = alloca(sizeof(*tarval_string) * (len));
 276                         for (i = 0; i < len; ++i) {
 277                                 tarval_string[i] = new_tarval_from_long(fname[i], mode_Bs);
 278                         }
 279                         set_entity_variability(ent, variability_constant);
 280                         set_array_entity_values(ent, tarval_string, len);
 281                 } else {
 282                         ent = entry->value;
 283                 }
 284                 wd->locs[wd->id].fname  = ent;
 285                 wd->locs[wd->id].lineno = lineno;
 286         } else {
 287                 wd->locs[wd->id].fname  = NULL;
 288                 wd->locs[wd->id].lineno = 0;
 289         }
 290 }
 291
 292 /**
 293  * Walker: assigns an ID to every block.
 294  * Builds the string table
 295  */
 296 static void
 297 block_id_walker(ir_node * bb, void * data)
 298 {
 299         block_id_walker_data_t *wd = data;
 300
 301         wd->array[wd->id] = new_tarval_from_long(get_irn_node_nr(bb), mode_Iu);
 302         instrument_block(bb, wd->symconst, wd->id);
 303
 304         if (wd->flags & profile_with_locations) {
 305                 dbg_info *dbg = get_irn_dbg_info(bb);
 306                 create_location_data(dbg, wd);
 307         }
 308         ++wd->id;
 309 }
 310
 311 #define IDENT(x)        new_id_from_chars(x, sizeof(x) - 1)
 312
 313 ir_graph *
 314 be_profile_instrument(const char *filename, unsigned flags)
 315 {
 316         int n, i;
 317         unsigned int n_blocks = 0;
 318         entity *bblock_id;
 319         entity *bblock_counts;
 320         entity *ent_filename;
 321         entity *ent_locations = NULL;
 322         entity *loc_lineno = NULL;
 323         entity *loc_name = NULL;
 324         entity *ent;
 325         ir_type *array_type;
 326         ir_type *uint_type;
 327         ir_type *string_type;
 328         ir_type *character_type;
 329         ir_type *loc_type = NULL;
 330         ir_type *charptr_type;
 331         ir_type *gtp;
 332         tarval **tarval_array;
 333         tarval **tarval_string;
 334         tarval *tv;
 335         int filename_len = strlen(filename)+1;
 336         ident *cur_ident;
 337         int align_l, align_n, size;
 338         ir_graph *rem;
 339         block_id_walker_data_t  wd;
 340         symconst_symbol sym;
 341
 342         /* count the number of block first */
 343         for (n = get_irp_n_irgs() - 1; n >= 0; --n) {
 344                 ir_graph *irg = get_irp_irg(n);
 345
 346                 n_blocks += count_blocks(irg);
 347         }
 348
 349         /* create all the necessary types and entities. Note that the
 350            types must have a fixed layout, because we already running in the
 351            backend */
 352         uint_type      = new_type_primitive(IDENT("__uint"), mode_Iu);
 353         set_type_alignment_bytes(uint_type, get_type_size_bytes(uint_type));
 354         array_type     = new_type_array(IDENT("__block_info_array"), 1, uint_type);
 355         set_array_bounds_int(array_type, 0, 0, n_blocks);
 356
 357         character_type = new_type_primitive(IDENT("__char"), mode_Bs);
 358         string_type    = new_type_array(IDENT("__filename"), 1, character_type);
 359         set_array_bounds_int(string_type, 0, 0, filename_len);
 360
 361         gtp            = get_glob_type();
 362
 363         cur_ident      = IDENT("__FIRMPROF__BLOCK_IDS");
 364         bblock_id      = new_entity(gtp, cur_ident, array_type);
 365         set_entity_ld_ident(bblock_id, cur_ident);
 366         set_entity_variability(bblock_id, variability_initialized);
 367
 368         cur_ident      = IDENT("__FIRMPROF__BLOCK_COUNTS");
 369         bblock_counts  = new_entity(gtp, cur_ident, array_type);
 370         set_entity_ld_ident(bblock_counts, cur_ident);
 371         set_entity_variability(bblock_counts, variability_initialized);
 372
 373         cur_ident      = IDENT("__FIRMPROF__FILE_NAME");
 374         ent_filename   = new_entity(gtp, cur_ident, string_type);
 375         set_entity_ld_ident(ent_filename, cur_ident);
 376
 377         if (flags & profile_with_locations) {
 378                 loc_type       = new_type_struct(IDENT("__location"));
 379                 loc_lineno     = new_entity(loc_type, IDENT("lineno"), uint_type);
 380                 align_l        = get_type_alignment_bytes(uint_type);
 381                 size           = get_type_size_bytes(uint_type);
 382                 set_entity_offset_bytes(loc_lineno, 0);
 383
 384                 charptr_type   = new_type_pointer(IDENT("__charptr"), character_type, mode_P_data);
 385                 align_n        = get_type_size_bytes(charptr_type);
 386                 set_type_alignment_bytes(charptr_type, align_n);
 387                 loc_name       = new_entity(loc_type, IDENT("name"), charptr_type);
 388                 size           = (size + align_n - 1) & -align_n;
 389                 set_entity_offset_bytes(loc_name, size);
 390                 size          += align_n;
 391
 392                 if (align_n > align_l)
 393                         align_l = align_n;
 394                 size = (size + align_l - 1) & -align_l;
 395                 set_type_size_bytes(loc_type, size);
 396                 set_type_state(loc_type, layout_fixed);
 397
 398                 loc_type = new_type_array(IDENT("__locarray"), 1, loc_type);
 399                 set_array_bounds_int(string_type, 0, 0, n_blocks);
 400
 401                 cur_ident      = IDENT("__FIRMPROF__LOCATIONS");
 402                 ent_locations   = new_entity(gtp, cur_ident, loc_type);
 403                 set_entity_ld_ident(ent_locations, cur_ident);
 404         }
 405
 406         /* initialize count array */
 407         NEW_ARR_A(tarval *, tarval_array, n_blocks);
 408         tv = get_tarval_null(mode_Iu);
 409         for (i = 0; i < n_blocks; ++i) {
 410                 tarval_array[i] = tv;
 411         }
 412         set_array_entity_values(bblock_counts, tarval_array, n_blocks);
 413
 414         /* initialize function name string constant */
 415         tarval_string = alloca(sizeof(*tarval_string) * (filename_len));
 416         for (i = 0; i < filename_len; ++i) {
 417                 tarval_string[i] = new_tarval_from_long(filename[i], mode_Bs);
 418         }
 419         set_entity_variability(ent_filename, variability_constant);
 420         set_array_entity_values(ent_filename, tarval_string, filename_len);
 421
 422         /* initialize block id array and instrument blocks */
 423         wd.array     = tarval_array;
 424         wd.id        = 0;
 425         wd.tp_char   = character_type;
 426         wd.flags     = flags;
 427         if (flags & profile_with_locations) {
 428                 wd.fname_map = pmap_create();
 429                 NEW_ARR_A(loc_entry, wd.locs, n_blocks);
 430         }
 431
 432         for (n = get_irp_n_irgs() - 1; n >= 0; --n) {
 433                 ir_graph      *irg = get_irp_irg(n);
 434                 int            i;
 435                 ir_node       *endbb = get_irg_end_block(irg);
 436                 fix_env       env;
 437
 438                 set_current_ir_graph(irg);
 439
 440                 /* generate a symbolic constant pointing to the count array */
 441                 sym.entity_p = bblock_counts;
 442                 wd.symconst  = new_r_SymConst(irg, get_irg_start_block(irg), sym, symconst_addr_ent);
 443
 444                 irg_block_walk_graph(irg, block_id_walker, NULL, &wd);
 445                 env.start_block = get_irg_start_block(irg);
 446                 env.end_block   = get_irg_end_block(irg);
 447                 set_irn_link(env.start_block, get_irg_no_mem(irg));
 448                 irg_block_walk_graph(irg, fix_ssa, NULL, &env);
 449                 for (i = get_Block_n_cfgpreds(endbb) - 1; i >= 0; --i) {
 450                         ir_node *node = skip_Proj(get_Block_cfgpred(endbb, i));
 451                         ir_node *bb   = get_Block_cfgpred_block(endbb, i);
 452                         ir_node *sync;
 453                         ir_node *ins[2];
 454
 455                         switch (get_irn_opcode(node)) {
 456                         case iro_Return:
 457                                 ins[0] = get_irn_link(bb);
 458                                 ins[1] = get_Return_mem(node);
 459                                 sync   = new_r_Sync(irg, bb, 2, ins);
 460                                 set_Return_mem(node, sync);
 461                                 break;
 462                         case iro_Raise:
 463                                 ins[0] = get_irn_link(bb);
 464                                 ins[1] = get_Raise_mem(node);
 465                                 sync   = new_r_Sync(irg, bb, 2, ins);
 466                                 set_Raise_mem(node, sync);
 467                                 break;
 468                         default:
 469                                 /* a fragile's op exception. There should be another path to End,
 470                                    so ignore it */
 471                                 assert(is_fragile_op(node) && "unexpected End control flow predecessor");
 472                         }
 473                 }
 474         }
 475         set_array_entity_values(bblock_id, tarval_array, n_blocks);
 476
 477         if (flags & profile_with_locations) {
 478                 /* build the initializer for the locations */
 479                 rem = current_ir_graph;
 480                 current_ir_graph = get_const_code_irg();
 481                 ent = get_array_element_entity(loc_type);
 482                 set_entity_variability(ent_locations, variability_constant);
 483                 for (i = 0; i < n_blocks; ++i) {
 484                         compound_graph_path *path;
 485                         tarval *tv;
 486                         ir_node *n;
 487
 488                         /* lineno */
 489                         path = new_compound_graph_path(loc_type, 2);
 490                         set_compound_graph_path_array_index(path, 0, i);
 491                         set_compound_graph_path_node(path, 0, ent);
 492                         set_compound_graph_path_node(path, 1, loc_lineno);
 493                         tv = new_tarval_from_long(wd.locs[i].lineno, mode_Iu);
 494                         add_compound_ent_value_w_path(ent_locations, new_Const(mode_Iu, tv), path);
 495
 496                         /* name */
 497                         path = new_compound_graph_path(loc_type, 2);
 498                         set_compound_graph_path_array_index(path, 0, i);
 499                         set_compound_graph_path_node(path, 0, ent);
 500                         set_compound_graph_path_node(path, 1, loc_name);
 501                         if (wd.locs[i].fname) {
 502                                 sym.entity_p = wd.locs[i].fname;
 503                                 n = new_SymConst(sym, symconst_addr_ent);
 504                         } else {
 505                                 n = new_Const(mode_P_data, get_mode_null(mode_P_data));
 506                         }
 507                         add_compound_ent_value_w_path(ent_locations, n, path);
 508                 }
 509                 pmap_destroy(wd.fname_map);
 510         }
 511         return gen_initializer_irg(ent_filename, bblock_id, bblock_counts, n_blocks);
 512 }
 513
 514 static void
 515 profile_node_info(void *ctx, FILE *f, const ir_node *irn)
 516 {
 517         if(is_Block(irn)) {
 518                 fprintf(f, "profiled execution count: %u\n", be_profile_get_block_execcount(irn));
 519         }
 520 }
 521
 522 static void
 523 register_vcg_hook(void)
 524 {
 525         memset(&hook, 0, sizeof(hook));
 526         hook.hook._hook_node_info = profile_node_info;
 527         register_hook(hook_node_info, &hook);
 528 }
 529
 530 static void
 531 unregister_vcg_hook(void)
 532 {
 533         unregister_hook(hook_node_info, &hook);
 534 }
 535
 536 /**
 537  * Reads the corresponding profile info file if it exists and returns a
 538  * profile info struct
 539  */
 540 void
 541 be_profile_read(const char *filename)
 542 {
 543         FILE   *f;
 544         char    buf[8];
 545         size_t  ret;
 546
 547         f = fopen(filename, "r");
 548         if(f == NULL) {
 549                 return;
 550         }
 551         printf("found profile data '%s'.\n", filename);
 552
 553         /* check magic */
 554         ret = fread(buf, 8, 1, f);
 555         if(ret == 0 || strncmp(buf, "firmprof", 8) != 0) {
 556                 return;
 557         }
 558
 559         if(profile) be_profile_free();
 560         profile = new_set(cmp_execcount, 16);
 561
 562         do {
 563                 execcount_t  query;
 564                 ret = fread(&query, sizeof(unsigned int), 2, f);
 565
 566                 if(ret != 2) break;
 567
 568                 set_insert(profile, &query, sizeof(query), query.block);
 569         } while(1);
 570
 571         fclose(f);
 572         register_vcg_hook();
 573 }
 574
 575 /**
 576  * Frees the profile info
 577  */
 578 void
 579 be_profile_free(void)
 580 {
 581         if(profile) {
 582                 unregister_vcg_hook();
 583                 del_set(profile);
 584         }
 585 }
 586
 587 /**
 588  * Tells whether profile module has acquired data
 589  */
 590 int
 591 be_profile_has_data(void)
 592 {
 593         return (profile != NULL);
 594 }
 595
 596 /**
 597  * Get block execution count as determined be profiling
 598  */
 599 unsigned int
 600 be_profile_get_block_execcount(const ir_node *block)
 601 {
 602         execcount_t *ec, query;
 603
 604         if(!profile)
 605                 return 1;
 606
 607         query.block = get_irn_node_nr(block);
 608         ec = set_find(profile, &query, sizeof(query), get_irn_node_nr(block));
 609
 610         if(ec != NULL) {
 611                 return ec->count;
 612         } else {
 613                 ir_fprintf(stderr, "Warning: Profile contains no data for %+F\n",
 614                            block);
 615                 return 1;
 616         }
 617 }
 618
 619 typedef struct _intialize_execfreq_env_t {
 620         ir_graph *irg;
 621         ir_exec_freq *execfreqs;
 622         double freq_factor;
 623 } initialize_execfreq_env_t;
 624
 625 // minimal execution frequency (an execfreq of 0 confuses algos)
 626 static const double MIN_EXECFREQ = 0.00001;
 627
 628 static void initialize_execfreq(ir_node *block, void *data) {
 629         initialize_execfreq_env_t *env = data;
 630         double freq;
 631
 632         if(block == get_irg_start_block(env->irg)
 633            || block == get_irg_end_block(env->irg)) {
 634                 freq = 1.0;
 635         } else {
 636                 freq = be_profile_get_block_execcount(block);
 637                 freq *= env->freq_factor;
 638                 if(freq < MIN_EXECFREQ)
 639                         freq = MIN_EXECFREQ;
 640         }
 641
 642         set_execfreq(env->execfreqs, block, freq);
 643 }
 644
 645 ir_exec_freq *be_create_execfreqs_from_profile(ir_graph *irg)
 646 {
 647         ir_node *block2 = NULL;
 648         ir_node *start_block;
 649         const ir_edge_t *edge;
 650         initialize_execfreq_env_t env;
 651         unsigned count;
 652
 653         env.irg = irg;
 654         env.execfreqs = create_execfreq(irg);
 655
 656         // find the successor to the start block
 657         start_block = get_irg_start_block(irg);
 658         foreach_block_succ(start_block, edge) {
 659                 ir_node *succ = get_edge_src_irn(edge);
 660                 if(succ != start_block) {
 661                         block2 = succ;
 662                         break;
 663                 }
 664         }
 665         assert(block2 != NULL);
 666
 667         count = be_profile_get_block_execcount(block2);
 668         if(count == 0) {
 669                 // the function was never executed, so fallback to estimated freqs
 670                 free_execfreq(env.execfreqs);
 671
 672                 return compute_execfreq(irg, 10);
 673         }
 674
 675         env.freq_factor = 1.0 / count;
 676         irg_block_walk_graph(irg, initialize_execfreq, NULL, &env);
 677
 678         return env.execfreqs;
 679 }