1 /* call_graph.c - Create call graphs.
2
3 Copyright (C) 1999-2023 Free Software Foundation, Inc.
4
5 This file is part of GNU Binutils.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
20 02110-1301, USA. */
21
22 #include "gprof.h"
23 #include "search_list.h"
24 #include "source.h"
25 #include "symtab.h"
26 #include "cg_arcs.h"
27 #include "call_graph.h"
28 #include "corefile.h"
29 #include "gmon_io.h"
30 #include "gmon_out.h"
31 #include "sym_ids.h"
32
33 void
34 cg_tally (bfd_vma from_pc, bfd_vma self_pc, unsigned long count)
35 {
36 Sym *parent;
37 Sym *child;
38
39 parent = sym_lookup (&symtab, from_pc);
40 child = sym_lookup (&symtab, self_pc);
41
42 if (child == NULL || parent == NULL)
43 return;
44
45 /* If we're doing line-by-line profiling, both the parent and the
46 child will probably point to line symbols instead of function
47 symbols. For the parent this is fine, since this identifies the
48 line number in the calling routing, but the child should always
49 point to a function entry point, so we back up in the symbol
50 table until we find it.
51
52 For normal profiling, is_func will be set on all symbols, so this
53 code will do nothing. */
54 while (child >= symtab.base && ! child->is_func)
55 --child;
56
57 if (child < symtab.base)
58 return;
59
60 /* Keep arc if it is on INCL_ARCS table or if the INCL_ARCS table
61 is empty and it is not in the EXCL_ARCS table. */
62 if (sym_id_arc_is_present (&syms[INCL_ARCS], parent, child)
63 || (syms[INCL_ARCS].len == 0
64 && !sym_id_arc_is_present (&syms[EXCL_ARCS], parent, child)))
65 {
66 child->ncalls += count;
67 DBG (TALLYDEBUG,
68 printf (_("[cg_tally] arc from %s to %s traversed %lu times\n"),
69 parent->name, child->name, count));
70 arc_add (parent, child, count);
71 }
72 }
73
74 /* Read a record from file IFP describing an arc in the function
75 call-graph and the count of how many times the arc has been
76 traversed. FILENAME is the name of file IFP and is provided
77 for formatting error-messages only. */
78
79 void
80 cg_read_rec (FILE *ifp, const char *filename)
81 {
82 bfd_vma from_pc, self_pc;
83 unsigned int count;
84
85 if (gmon_io_read_vma (ifp, &from_pc)
86 || gmon_io_read_vma (ifp, &self_pc)
87 || gmon_io_read_32 (ifp, &count))
88 {
89 fprintf (stderr, _("%s: %s: unexpected end of file\n"),
90 whoami, filename);
91 done (1);
92 }
93
94 DBG (SAMPLEDEBUG,
95 printf ("[cg_read_rec] frompc 0x%lx selfpc 0x%lx count %lu\n",
96 (unsigned long) from_pc, (unsigned long) self_pc,
97 (unsigned long) count));
98 /* Add this arc: */
99 cg_tally (from_pc, self_pc, count);
100 }
101
102 /* Write all the arcs in the call-graph to file OFP. FILENAME is
103 the name of OFP and is provided for formatting error-messages
104 only. */
105
106 void
107 cg_write_arcs (FILE *ofp, const char *filename)
108 {
109 Arc *arc;
110 Sym *sym;
111
112 for (sym = symtab.base; sym < symtab.limit; sym++)
113 {
114 for (arc = sym->cg.children; arc; arc = arc->next_child)
115 {
116 if (gmon_io_write_8 (ofp, GMON_TAG_CG_ARC)
117 || gmon_io_write_vma (ofp, arc->parent->addr)
118 || gmon_io_write_vma (ofp, arc->child->addr)
119 || gmon_io_write_32 (ofp, arc->count))
120 {
121 perror (filename);
122 done (1);
123 }
124 DBG (SAMPLEDEBUG,
125 printf ("[cg_write_arcs] frompc 0x%lx selfpc 0x%lx count %lu\n",
126 (unsigned long) arc->parent->addr,
127 (unsigned long) arc->child->addr, arc->count));
128 }
129 }
130 }