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1 /*--------------------------------------------------------------------*/
2 /*--- Callgrind                                                    ---*/
3 /*---                                                      ct_fn.c ---*/
4 /*--------------------------------------------------------------------*/
5 
6 /*
7    This file is part of Callgrind, a Valgrind tool for call tracing.
8 
9    Copyright (C) 2002-2017, Josef Weidendorfer (Josef.Weidendorfer@gmx.de)
10 
11    This program is free software; you can redistribute it and/or
12    modify it under the terms of the GNU General Public License as
13    published by the Free Software Foundation; either version 2 of the
14    License, or (at your option) any later version.
15 
16    This program is distributed in the hope that it will be useful, but
17    WITHOUT ANY WARRANTY; without even the implied warranty of
18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
19    General Public License for more details.
20 
21    You should have received a copy of the GNU General Public License
22    along with this program; if not, write to the Free Software
23    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
24    02111-1307, USA.
25 
26    The GNU General Public License is contained in the file COPYING.
27 */
28 
29 #include "global.h"
30 
31 #define N_INITIAL_FN_ARRAY_SIZE 10071
32 
33 static fn_array current_fn_active;
34 
35 static Addr runtime_resolve_addr = 0;
36 static int  runtime_resolve_length = 0;
37 
38 // a code pattern is a list of tuples (start offset, length)
39 struct chunk_t { int start, len; };
40 struct pattern
41 {
42     const HChar* name;
43     int len;
44     struct chunk_t chunk[];
45 };
46 
47 /* Scan for a pattern in the code of an ELF object.
48  * If found, return true and set runtime_resolve_{addr,length}
49  */
50 __attribute__((unused))    // Possibly;  depends on the platform.
check_code(obj_node * obj,UChar code[],struct pattern * pat)51 static Bool check_code(obj_node* obj,
52                        UChar code[], struct pattern* pat)
53 {
54     Bool found;
55     Addr addr, end;
56     int chunk, start, len;
57 
58     /* first chunk of pattern should always start at offset 0 and
59      * have at least 3 bytes */
60     CLG_ASSERT((pat->chunk[0].start == 0) && (pat->chunk[0].len >2));
61 
62     CLG_DEBUG(1, "check_code: %s, pattern %s, check %d bytes of [%x %x %x...]\n",
63               obj->name, pat->name, pat->chunk[0].len, code[0], code[1], code[2]);
64 
65     end = obj->start + obj->size - pat->len;
66     addr = obj->start;
67     while(addr < end) {
68 	found = (VG_(memcmp)( (void*)addr, code, pat->chunk[0].len) == 0);
69 
70         if (found) {
71 	    chunk = 1;
72 	    while(1) {
73 		start = pat->chunk[chunk].start;
74 		len   = pat->chunk[chunk].len;
75 		if (len == 0) break;
76 
77 		CLG_ASSERT(len >2);
78                 CLG_DEBUG(1, " found chunk %d at %#lx, checking %d bytes "
79                              "of [%x %x %x...]\n",
80                           chunk-1, addr - obj->start, len,
81 			  code[start], code[start+1], code[start+2]);
82 
83                 if (VG_(memcmp)( (void*)(addr+start), code+start, len) != 0) {
84                     found = False;
85                     break;
86                 }
87 		chunk++;
88 	    }
89 
90             if (found) {
91 		CLG_DEBUG(1, "found at offset %#lx.\n", addr - obj->start);
92 		if (VG_(clo_verbosity) > 1)
93 		    VG_(message)(Vg_DebugMsg, "Found runtime_resolve (%s): "
94                                               "%s +%#lx=%#lx, length %d\n",
95 				 pat->name, obj->name + obj->last_slash_pos,
96 				 addr - obj->start, addr, pat->len);
97 
98 		runtime_resolve_addr   = addr;
99 		runtime_resolve_length = pat->len;
100 		return True;
101 	    }
102         }
103         addr++;
104     }
105     CLG_DEBUG(1, " found nothing.\n");
106     return False;
107 }
108 
109 
110 /* _ld_runtime_resolve, located in ld.so, needs special handling:
111  * The jump at end into the resolved function should not be
112  * represented as a call (as usually done in callgrind with jumps),
113  * but as a return + call. Otherwise, the repeated existence of
114  * _ld_runtime_resolve in call chains will lead to huge cycles,
115  * making the profile almost worthless.
116  *
117  * If ld.so is stripped, the symbol will not appear. But as this
118  * function is handcrafted assembler, we search for it.
119  *
120  * We stop if the ELF object name does not seem to be the runtime linker
121  */
search_runtime_resolve(obj_node * obj)122 static Bool search_runtime_resolve(obj_node* obj)
123 {
124 #if defined(VGP_x86_linux)
125     static UChar code[] = {
126 	/* 0*/ 0x50, 0x51, 0x52, 0x8b, 0x54, 0x24, 0x10, 0x8b,
127 	/* 8*/ 0x44, 0x24, 0x0c, 0xe8, 0x70, 0x01, 0x00, 0x00,
128 	/*16*/ 0x5a, 0x59, 0x87, 0x04, 0x24, 0xc2, 0x08, 0x00 };
129     /* Check ranges [0-11] and [16-23] ([12-15] is an absolute address) */
130     static struct pattern pat = {
131 	"x86-def", 24, {{ 0,12 }, { 16,8 }, { 24,0}} };
132 
133     /* Pattern for glibc-2.8 on OpenSuse11.0 */
134     static UChar code_28[] = {
135 	/* 0*/ 0x50, 0x51, 0x52, 0x8b, 0x54, 0x24, 0x10, 0x8b,
136 	/* 8*/ 0x44, 0x24, 0x0c, 0xe8, 0x70, 0x01, 0x00, 0x00,
137 	/*16*/ 0x5a, 0x8b, 0x0c, 0x24, 0x89, 0x04, 0x24, 0x8b,
138 	/*24*/ 0x44, 0x24, 0x04, 0xc2, 0x0c, 0x00 };
139     static struct pattern pat_28 = {
140 	"x86-glibc2.8", 30, {{ 0,12 }, { 16,14 }, { 30,0}} };
141 
142     if (VG_(strncmp)(obj->name, "/lib/ld", 7) != 0) return False;
143     if (check_code(obj, code, &pat)) return True;
144     if (check_code(obj, code_28, &pat_28)) return True;
145     return False;
146 #endif
147 
148 #if defined(VGP_ppc32_linux)
149     static UChar code[] = {
150 	/* 0*/ 0x94, 0x21, 0xff, 0xc0, 0x90, 0x01, 0x00, 0x0c,
151 	/* 8*/ 0x90, 0x61, 0x00, 0x10, 0x90, 0x81, 0x00, 0x14,
152 	/*16*/ 0x7d, 0x83, 0x63, 0x78, 0x90, 0xa1, 0x00, 0x18,
153 	/*24*/ 0x7d, 0x64, 0x5b, 0x78, 0x90, 0xc1, 0x00, 0x1c,
154 	/*32*/ 0x7c, 0x08, 0x02, 0xa6, 0x90, 0xe1, 0x00, 0x20,
155 	/*40*/ 0x90, 0x01, 0x00, 0x30, 0x91, 0x01, 0x00, 0x24,
156 	/*48*/ 0x7c, 0x00, 0x00, 0x26, 0x91, 0x21, 0x00, 0x28,
157 	/*56*/ 0x91, 0x41, 0x00, 0x2c, 0x90, 0x01, 0x00, 0x08,
158 	/*64*/ 0x48, 0x00, 0x02, 0x91, 0x7c, 0x69, 0x03, 0xa6, /* at 64: bl aff0 <fixup> */
159 	/*72*/ 0x80, 0x01, 0x00, 0x30, 0x81, 0x41, 0x00, 0x2c,
160 	/*80*/ 0x81, 0x21, 0x00, 0x28, 0x7c, 0x08, 0x03, 0xa6,
161 	/*88*/ 0x81, 0x01, 0x00, 0x24, 0x80, 0x01, 0x00, 0x08,
162 	/*96*/ 0x80, 0xe1, 0x00, 0x20, 0x80, 0xc1, 0x00, 0x1c,
163 	/*104*/0x7c, 0x0f, 0xf1, 0x20, 0x80, 0xa1, 0x00, 0x18,
164 	/*112*/0x80, 0x81, 0x00, 0x14, 0x80, 0x61, 0x00, 0x10,
165 	/*120*/0x80, 0x01, 0x00, 0x0c, 0x38, 0x21, 0x00, 0x40,
166 	/*128*/0x4e, 0x80, 0x04, 0x20 };
167     static struct pattern pat = {
168 	"ppc32-def", 132, {{ 0,65 }, { 68,64 }, { 132,0 }} };
169 
170     if (VG_(strncmp)(obj->name, "/lib/ld", 7) != 0) return False;
171     return check_code(obj, code, &pat);
172 #endif
173 
174 #if defined(VGP_amd64_linux)
175     static UChar code[] = {
176 	/* 0*/ 0x48, 0x83, 0xec, 0x38, 0x48, 0x89, 0x04, 0x24,
177 	/* 8*/ 0x48, 0x89, 0x4c, 0x24, 0x08, 0x48, 0x89, 0x54, 0x24, 0x10,
178 	/*18*/ 0x48, 0x89, 0x74, 0x24, 0x18, 0x48, 0x89, 0x7c, 0x24, 0x20,
179 	/*28*/ 0x4c, 0x89, 0x44, 0x24, 0x28, 0x4c, 0x89, 0x4c, 0x24, 0x30,
180 	/*38*/ 0x48, 0x8b, 0x74, 0x24, 0x40, 0x49, 0x89, 0xf3,
181 	/*46*/ 0x4c, 0x01, 0xde, 0x4c, 0x01, 0xde, 0x48, 0xc1, 0xe6, 0x03,
182 	/*56*/ 0x48, 0x8b, 0x7c, 0x24, 0x38, 0xe8, 0xee, 0x01, 0x00, 0x00,
183 	/*66*/ 0x49, 0x89, 0xc3, 0x4c, 0x8b, 0x4c, 0x24, 0x30,
184 	/*74*/ 0x4c, 0x8b, 0x44, 0x24, 0x28, 0x48, 0x8b, 0x7c, 0x24, 0x20,
185 	/*84*/ 0x48, 0x8b, 0x74, 0x24, 0x18, 0x48, 0x8b, 0x54, 0x24, 0x10,
186 	/*94*/ 0x48, 0x8b, 0x4c, 0x24, 0x08, 0x48, 0x8b, 0x04, 0x24,
187 	/*103*/0x48, 0x83, 0xc4, 0x48, 0x41, 0xff, 0xe3 };
188     static struct pattern pat = {
189 	"amd64-def", 110, {{ 0,62 }, { 66,44 }, { 110,0 }} };
190 
191     if ((VG_(strncmp)(obj->name, "/lib/ld", 7) != 0) &&
192 	(VG_(strncmp)(obj->name, "/lib64/ld", 9) != 0)) return False;
193     return check_code(obj, code, &pat);
194 #endif
195 
196     /* For other platforms, no patterns known */
197     return False;
198 }
199 
200 
201 /*------------------------------------------------------------*/
202 /*--- Object/File/Function hash entry operations           ---*/
203 /*------------------------------------------------------------*/
204 
205 /* Object hash table, fixed */
206 static obj_node* obj_table[N_OBJ_ENTRIES];
207 
CLG_(init_obj_table)208 void CLG_(init_obj_table)()
209 {
210     Int i;
211     for (i = 0; i < N_OBJ_ENTRIES; i++)
212 	obj_table[i] = 0;
213 }
214 
215 #define HASH_CONSTANT   256
216 
str_hash(const HChar * s,UInt table_size)217 static UInt str_hash(const HChar *s, UInt table_size)
218 {
219     int hash_value = 0;
220     for ( ; *s; s++)
221         hash_value = (HASH_CONSTANT * hash_value + *s) % table_size;
222     return hash_value;
223 }
224 
225 
226 static const HChar* anonymous_obj = "???";
227 
228 static __inline__
new_obj_node(DebugInfo * di,obj_node * next)229 obj_node* new_obj_node(DebugInfo* di, obj_node* next)
230 {
231    Int i;
232    obj_node* obj;
233 
234    obj = (obj_node*) CLG_MALLOC("cl.fn.non.1", sizeof(obj_node));
235    obj->name  = di ? VG_(strdup)( "cl.fn.non.2",
236                                   VG_(DebugInfo_get_filename)(di) )
237                    : anonymous_obj;
238    for (i = 0; i < N_FILE_ENTRIES; i++) {
239       obj->files[i] = NULL;
240    }
241    CLG_(stat).distinct_objs ++;
242    obj->number  = CLG_(stat).distinct_objs;
243    /* JRS 2008 Feb 19: maybe rename .start/.size/.offset to
244       .text_avma/.text_size/.test_bias to make it clearer what these
245       fields really mean */
246    obj->start   = di ? VG_(DebugInfo_get_text_avma)(di) : 0;
247    obj->size    = di ? VG_(DebugInfo_get_text_size)(di) : 0;
248    obj->offset  = di ? VG_(DebugInfo_get_text_bias)(di) : 0;
249    obj->next    = next;
250 
251    // not only used for debug output (see static.c)
252    obj->last_slash_pos = 0;
253    i = 0;
254    while(obj->name[i]) {
255 	if (obj->name[i]=='/') obj->last_slash_pos = i+1;
256 	i++;
257    }
258 
259    if (runtime_resolve_addr == 0) search_runtime_resolve(obj);
260 
261    return obj;
262 }
263 
CLG_(get_obj_node)264 obj_node* CLG_(get_obj_node)(DebugInfo* di)
265 {
266     obj_node*    curr_obj_node;
267     UInt         objname_hash;
268     const HChar* obj_name;
269 
270     obj_name = di ? VG_(DebugInfo_get_filename)(di) : anonymous_obj;
271 
272     /* lookup in obj hash */
273     objname_hash = str_hash(obj_name, N_OBJ_ENTRIES);
274     curr_obj_node = obj_table[objname_hash];
275     while (NULL != curr_obj_node &&
276 	   VG_(strcmp)(obj_name, curr_obj_node->name) != 0) {
277 	curr_obj_node = curr_obj_node->next;
278     }
279     if (NULL == curr_obj_node) {
280 	obj_table[objname_hash] = curr_obj_node =
281 	    new_obj_node(di, obj_table[objname_hash]);
282     }
283 
284     return curr_obj_node;
285 }
286 
287 
288 static __inline__
new_file_node(const HChar * filename,obj_node * obj,file_node * next)289 file_node* new_file_node(const HChar *filename,
290 			 obj_node* obj, file_node* next)
291 {
292   Int i;
293   file_node* file = (file_node*) CLG_MALLOC("cl.fn.nfn.1",
294                                            sizeof(file_node));
295   file->name  = VG_(strdup)("cl.fn.nfn.2", filename);
296   for (i = 0; i < N_FN_ENTRIES; i++) {
297     file->fns[i] = NULL;
298   }
299   CLG_(stat).distinct_files++;
300   file->number  = CLG_(stat).distinct_files;
301   file->obj     = obj;
302   file->next      = next;
303   return file;
304 }
305 
306 
CLG_(get_file_node)307 file_node* CLG_(get_file_node)(obj_node* curr_obj_node,
308                                const HChar *dir, const HChar *file)
309 {
310     file_node* curr_file_node;
311     UInt       filename_hash;
312 
313     /* Build up an absolute pathname, if there is a directory available */
314     HChar filename[VG_(strlen)(dir) + 1 + VG_(strlen)(file) + 1];
315     VG_(strcpy)(filename, dir);
316     if (filename[0] != '\0') {
317        VG_(strcat)(filename, "/");
318     }
319     VG_(strcat)(filename, file);
320 
321     /* lookup in file hash */
322     filename_hash = str_hash(filename, N_FILE_ENTRIES);
323     curr_file_node = curr_obj_node->files[filename_hash];
324     while (NULL != curr_file_node &&
325 	   VG_(strcmp)(filename, curr_file_node->name) != 0) {
326 	curr_file_node = curr_file_node->next;
327     }
328     if (NULL == curr_file_node) {
329 	curr_obj_node->files[filename_hash] = curr_file_node =
330 	    new_file_node(filename, curr_obj_node,
331 			  curr_obj_node->files[filename_hash]);
332     }
333 
334     return curr_file_node;
335 }
336 
337 /* forward decl. */
338 static void resize_fn_array(void);
339 
340 static __inline__
new_fn_node(const HChar * fnname,file_node * file,fn_node * next)341 fn_node* new_fn_node(const HChar *fnname,
342 		     file_node* file, fn_node* next)
343 {
344     fn_node* fn = (fn_node*) CLG_MALLOC("cl.fn.nfnnd.1",
345                                          sizeof(fn_node));
346     fn->name = VG_(strdup)("cl.fn.nfnnd.2", fnname);
347 
348     CLG_(stat).distinct_fns++;
349     fn->number   = CLG_(stat).distinct_fns;
350     fn->last_cxt = 0;
351     fn->pure_cxt = 0;
352     fn->file     = file;
353     fn->next     = next;
354 
355     fn->dump_before  = False;
356     fn->dump_after   = False;
357     fn->zero_before  = False;
358     fn->toggle_collect = False;
359     fn->skip         = False;
360     fn->pop_on_jump  = CLG_(clo).pop_on_jump;
361     fn->is_malloc    = False;
362     fn->is_realloc   = False;
363     fn->is_free      = False;
364 
365     fn->group        = 0;
366     fn->separate_callers    = CLG_(clo).separate_callers;
367     fn->separate_recursions = CLG_(clo).separate_recursions;
368 
369 #if CLG_ENABLE_DEBUG
370     fn->verbosity    = -1;
371 #endif
372 
373     if (CLG_(stat).distinct_fns >= current_fn_active.size)
374 	resize_fn_array();
375 
376     return fn;
377 }
378 
379 
380 /* Get a function node in hash2 with known file node.
381  * hash nodes are created if needed
382  */
383 static
get_fn_node_infile(file_node * curr_file_node,const HChar * fnname)384 fn_node* get_fn_node_infile(file_node* curr_file_node,
385 			    const HChar *fnname)
386 {
387     fn_node* curr_fn_node;
388     UInt     fnname_hash;
389 
390     CLG_ASSERT(curr_file_node != 0);
391 
392     /* lookup in function hash */
393     fnname_hash = str_hash(fnname, N_FN_ENTRIES);
394     curr_fn_node = curr_file_node->fns[fnname_hash];
395     while (NULL != curr_fn_node &&
396 	   VG_(strcmp)(fnname, curr_fn_node->name) != 0) {
397 	curr_fn_node = curr_fn_node->next;
398     }
399     if (NULL == curr_fn_node) {
400 	curr_file_node->fns[fnname_hash] = curr_fn_node =
401             new_fn_node(fnname, curr_file_node,
402 			curr_file_node->fns[fnname_hash]);
403     }
404 
405     return curr_fn_node;
406 }
407 
408 
409 /* Get a function node in a Segment.
410  * Hash nodes are created if needed.
411  */
412 static __inline__
get_fn_node_inseg(DebugInfo * di,const HChar * dirname,const HChar * filename,const HChar * fnname)413 fn_node* get_fn_node_inseg(DebugInfo* di,
414 			   const HChar *dirname,
415 			   const HChar *filename,
416 			   const HChar *fnname)
417 {
418   obj_node  *obj  = CLG_(get_obj_node)(di);
419   file_node *file = CLG_(get_file_node)(obj, dirname, filename);
420   fn_node   *fn   = get_fn_node_infile(file, fnname);
421 
422   return fn;
423 }
424 
425 
CLG_(get_debug_info)426 Bool CLG_(get_debug_info)(Addr instr_addr,
427                           const HChar **dir,
428                           const HChar **file,
429                           const HChar **fn_name, UInt* line_num,
430                           DebugInfo** pDebugInfo)
431 {
432   Bool found_file_line, found_fn, result = True;
433   UInt line;
434 
435   CLG_DEBUG(6, "  + get_debug_info(%#lx)\n", instr_addr);
436 
437   if (pDebugInfo) {
438       *pDebugInfo = VG_(find_DebugInfo)(instr_addr);
439 
440       // for generated code in anonymous space, pSegInfo is 0
441    }
442 
443    found_file_line = VG_(get_filename_linenum)(instr_addr,
444 					       file,
445 					       dir,
446 					       &line);
447    found_fn = VG_(get_fnname)(instr_addr, fn_name);
448 
449    if (!found_file_line && !found_fn) {
450      CLG_(stat).no_debug_BBs++;
451      *file = "???";
452      *fn_name = "???";
453      if (line_num) *line_num=0;
454      result = False;
455 
456    } else if ( found_file_line &&  found_fn) {
457      CLG_(stat).full_debug_BBs++;
458      if (line_num) *line_num=line;
459 
460    } else if ( found_file_line && !found_fn) {
461      CLG_(stat).file_line_debug_BBs++;
462      *fn_name = "???";
463      if (line_num) *line_num=line;
464 
465    } else  /*(!found_file_line &&  found_fn)*/ {
466      CLG_(stat).fn_name_debug_BBs++;
467      *file = "???";
468      if (line_num) *line_num=0;
469    }
470 
471    CLG_DEBUG(6, "  - get_debug_info(%#lx): seg '%s', fn %s\n",
472 	    instr_addr,
473 	    !pDebugInfo   ? "-" :
474 	    (*pDebugInfo) ? VG_(DebugInfo_get_filename)(*pDebugInfo) :
475 	    "(None)",
476 	    *fn_name);
477 
478   return result;
479 }
480 
481 /* for _libc_freeres_wrapper => _exit renaming */
482 static BB* exit_bb = 0;
483 
484 
485 /*
486  * Attach function struct to a BB from debug info.
487  */
CLG_(get_fn_node)488 fn_node* CLG_(get_fn_node)(BB* bb)
489 {
490     const HChar *fnname, *filename, *dirname;
491     DebugInfo* di;
492     UInt       line_num;
493     fn_node*   fn;
494 
495     /* fn from debug info is idempotent for a BB */
496     if (bb->fn) return bb->fn;
497 
498     CLG_DEBUG(3,"+ get_fn_node(BB %#lx)\n", bb_addr(bb));
499 
500     /* get function/file name, line number and object of
501      * the BB according to debug information
502      */
503     CLG_(get_debug_info)(bb_addr(bb),
504                          &dirname, &filename, &fnname, &line_num, &di);
505 
506     if (0 == VG_(strcmp)(fnname, "???")) {
507 	int p;
508         static HChar buf[32];  // for sure large enough
509 	/* Use address as found in library */
510 	if (sizeof(Addr) == 4)
511           p = VG_(sprintf)(buf, "%#08lx", (UWord)bb->offset);
512 	else
513 	    // 64bit address
514           p = VG_(sprintf)(buf, "%#016lx", (UWord)bb->offset);
515 
516 	VG_(sprintf)(buf + p, "%s",
517 		     (bb->sect_kind == Vg_SectData) ? " [Data]" :
518 		     (bb->sect_kind == Vg_SectBSS)  ? " [BSS]"  :
519 		     (bb->sect_kind == Vg_SectGOT)  ? " [GOT]"  :
520 		     (bb->sect_kind == Vg_SectPLT)  ? " [PLT]"  : "");
521         fnname = buf;
522     }
523     else {
524       if (VG_(get_fnname_if_entry)(bb_addr(bb), &fnname))
525 	bb->is_entry = 1;
526     }
527 
528     /* HACK for correct _exit:
529      * _exit is redirected to VG_(__libc_freeres_wrapper) by valgrind,
530      * so we rename it back again :-)
531      */
532     if (0 == VG_(strcmp)(fnname, "vgPlain___libc_freeres_wrapper")
533 	&& exit_bb) {
534       CLG_(get_debug_info)(bb_addr(exit_bb),
535                            &dirname, &filename, &fnname, &line_num, &di);
536 
537 	CLG_DEBUG(1, "__libc_freeres_wrapper renamed to _exit\n");
538     }
539     if (0 == VG_(strcmp)(fnname, "_exit") && !exit_bb)
540 	exit_bb = bb;
541 
542     if (runtime_resolve_addr &&
543 	(bb_addr(bb) >= runtime_resolve_addr) &&
544 	(bb_addr(bb) < runtime_resolve_addr + runtime_resolve_length)) {
545 	/* BB in runtime_resolve found by code check; use this name */
546       fnname = "_dl_runtime_resolve";
547     }
548 
549     /* get fn_node struct for this function */
550     fn = get_fn_node_inseg( di, dirname, filename, fnname);
551 
552     /* if this is the 1st time the function is seen,
553      * some attributes are set */
554     if (fn->pure_cxt == 0) {
555 
556       /* Every function gets a "pure" context, i.e. a context with stack
557        * depth 1 only with this function. This is for compression of mangled
558        * names
559        */
560       fn_node* pure[2];
561       pure[0] = 0;
562       pure[1] = fn;
563       fn->pure_cxt = CLG_(get_cxt)(pure+1);
564 
565       if (bb->sect_kind == Vg_SectPLT)
566 	fn->skip = CLG_(clo).skip_plt;
567 
568       if (VG_(strcmp)(fn->name, "_dl_runtime_resolve")==0) {
569 	  fn->pop_on_jump = True;
570 
571 	  if (VG_(clo_verbosity) > 1)
572 	      VG_(message)(Vg_DebugMsg, "Symbol match: found runtime_resolve:"
573                                         " %s +%#lx=%#lx\n",
574 		      bb->obj->name + bb->obj->last_slash_pos,
575                       (UWord)bb->offset, bb_addr(bb));
576       }
577 
578       fn->is_malloc  = (VG_(strcmp)(fn->name, "malloc")==0);
579       fn->is_realloc = (VG_(strcmp)(fn->name, "realloc")==0);
580       fn->is_free    = (VG_(strcmp)(fn->name, "free")==0);
581 
582       /* apply config options from function name patterns
583        * given on command line */
584       CLG_(update_fn_config)(fn);
585     }
586 
587 
588     bb->fn   = fn;
589     bb->line = line_num;
590 
591     if (dirname[0]) {
592        CLG_DEBUG(3,"- get_fn_node(BB %#lx): %s (in %s:%u)\n",
593                  bb_addr(bb), fnname, filename, line_num);
594     } else
595        CLG_DEBUG(3,"- get_fn_node(BB %#lx): %s (in %s/%s:%u)\n",
596                  bb_addr(bb), fnname, dirname, filename, line_num);
597 
598     return fn;
599 }
600 
601 
602 /*------------------------------------------------------------*/
603 /*--- Active function array operations                     ---*/
604 /*------------------------------------------------------------*/
605 
606 /* The active function array is a thread-specific array
607  * of UInts, mapping function numbers to the active count of
608  * functions.
609  * The active count is the number of times a function appears
610  * in the current call stack, and is used when costs for recursion
611  * levels should be separated.
612  */
613 
CLG_(get_fn_entry)614 UInt* CLG_(get_fn_entry)(Int n)
615 {
616   CLG_ASSERT(n < current_fn_active.size);
617   return current_fn_active.array + n;
618 }
619 
CLG_(init_fn_array)620 void CLG_(init_fn_array)(fn_array* a)
621 {
622   Int i;
623 
624   CLG_ASSERT(a != 0);
625 
626   a->size = N_INITIAL_FN_ARRAY_SIZE;
627   if (a->size <= CLG_(stat).distinct_fns)
628     a->size = CLG_(stat).distinct_fns+1;
629 
630   a->array = (UInt*) CLG_MALLOC("cl.fn.gfe.1",
631                                 a->size * sizeof(UInt));
632   for(i=0;i<a->size;i++)
633     a->array[i] = 0;
634 }
635 
CLG_(copy_current_fn_array)636 void CLG_(copy_current_fn_array)(fn_array* dst)
637 {
638   CLG_ASSERT(dst != 0);
639 
640   dst->size  = current_fn_active.size;
641   dst->array = current_fn_active.array;
642 }
643 
CLG_(get_current_fn_array)644 fn_array* CLG_(get_current_fn_array)()
645 {
646   return &current_fn_active;
647 }
648 
CLG_(set_current_fn_array)649 void CLG_(set_current_fn_array)(fn_array* a)
650 {
651   CLG_ASSERT(a != 0);
652 
653   current_fn_active.size  = a->size;
654   current_fn_active.array = a->array;
655   if (current_fn_active.size <= CLG_(stat).distinct_fns)
656     resize_fn_array();
657 }
658 
659 /* ensure that active_array is big enough:
660  *  <distinct_fns> is the highest index, so <fn_active_array_size>
661  *  has to be bigger than that.
662  */
resize_fn_array(void)663 static void resize_fn_array(void)
664 {
665     UInt* new_array;
666     Int i;
667 
668     UInt newsize = current_fn_active.size;
669     while (newsize <= CLG_(stat).distinct_fns) newsize *=2;
670 
671     CLG_DEBUG(0, "Resize fn_active_array: %u => %u\n",
672 	     current_fn_active.size, newsize);
673 
674     new_array = (UInt*) CLG_MALLOC("cl.fn.rfa.1", newsize * sizeof(UInt));
675     for(i=0;i<current_fn_active.size;i++)
676       new_array[i] = current_fn_active.array[i];
677     while(i<newsize)
678 	new_array[i++] = 0;
679 
680     VG_(free)(current_fn_active.array);
681     current_fn_active.size = newsize;
682     current_fn_active.array = new_array;
683     CLG_(stat).fn_array_resizes++;
684 }
685 
686 
687