1
2Building and not installing it
3~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4To run Valgrind without having to install it, run coregrind/valgrind
5with the VALGRIND_LIB environment variable set, where <dir> is the root
6of the source tree (and must be an absolute path).  Eg:
7
8  VALGRIND_LIB=~/grind/head4/.in_place ~/grind/head4/coregrind/valgrind 
9
10This allows you to compile and run with "make" instead of "make install",
11saving you time.
12
13Or, you can use the 'vg-in-place' script which does that for you.
14
15I recommend compiling with "make --quiet" to further reduce the amount of
16output spewed out during compilation, letting you actually see any errors,
17warnings, etc.
18
19
20Building a distribution tarball
21~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
22To build a distribution tarball from the valgrind sources:
23
24  make dist
25
26In addition to compiling, linking and packaging everything up, the command
27will also build the documentation. Even if all required tools for building the
28documentation are installed, this step may not succeed because of hidden
29dependencies. E.g. on Ubuntu you must have "docbook-xsl" installed.
30Additionally, specific tool versions maybe needed.
31
32If you only want to test whether the generated tarball is complete and runs
33regression tests successfully, building documentation is not needed.
34Edit docs/Makefile.am, search for BUILD_ALL_DOCS and follow instructions there.
35
36
37Running the regression tests
38~~~~~~~~~~~~~~~~~~~~~~~~~~~~
39To build and run all the regression tests, run "make [--quiet] regtest".
40
41To run a subset of the regression tests, execute:
42
43  perl tests/vg_regtest <name>
44
45where <name> is a directory (all tests within will be run) or a single
46.vgtest test file, or the name of a program which has a like-named .vgtest
47file.  Eg:
48
49  perl tests/vg_regtest memcheck
50  perl tests/vg_regtest memcheck/tests/badfree.vgtest
51  perl tests/vg_regtest memcheck/tests/badfree
52
53
54Running the performance tests
55~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
56To build and run all the performance tests, run "make [--quiet] perf".
57
58To run a subset of the performance suite, execute:
59
60  perl perf/vg_perf <name>
61
62where <name> is a directory (all tests within will be run) or a single
63.vgperf test file, or the name of a program which has a like-named .vgperf
64file.  Eg:
65
66  perl perf/vg_perf perf/
67  perl perf/vg_perf perf/bz2.vgperf
68  perl perf/vg_perf perf/bz2
69
70To compare multiple versions of Valgrind, use the --vg= option multiple
71times.  For example, if you have two Valgrinds next to each other, one in
72trunk1/ and one in trunk2/, from within either trunk1/ or trunk2/ do this to
73compare them on all the performance tests:
74
75  perl perf/vg_perf --vg=../trunk1 --vg=../trunk2 perf/
76
77
78Debugging Valgrind with GDB
79~~~~~~~~~~~~~~~~~~~~~~~~~~~
80To debug the valgrind launcher program (<prefix>/bin/valgrind) just
81run it under gdb in the normal way.
82
83Debugging the main body of the valgrind code (and/or the code for
84a particular tool) requires a bit more trickery but can be achieved
85without too much problem by following these steps:
86
87(1) Set VALGRIND_LAUNCHER to point to the valgrind executable.  Eg:
88
89      export VALGRIND_LAUNCHER=/usr/local/bin/valgrind
90
91    or for an uninstalled version in a source directory $DIR:
92
93      export VALGRIND_LAUNCHER=$DIR/coregrind/valgrind
94
95(2) Run gdb on the tool executable.  Eg:
96
97      gdb /usr/local/lib/valgrind/ppc32-linux/lackey
98
99    or
100
101      gdb $DIR/.in_place/x86-linux/memcheck
102
103(3) Do "handle SIGSEGV SIGILL nostop noprint" in GDB to prevent GDB from
104    stopping on a SIGSEGV or SIGILL:
105
106    (gdb) handle SIGILL SIGSEGV nostop noprint
107
108(4) Set any breakpoints you want and proceed as normal for gdb. The
109    macro VG_(FUNC) is expanded to vgPlain_FUNC, so If you want to set
110    a breakpoint VG_(do_exec), you could do like this in GDB:
111
112    (gdb) b vgPlain_do_exec
113
114(5) Run the tool with required options:
115
116    (gdb) run pwd
117
118Steps (1)--(3) can be put in a .gdbinit file, but any directory names must
119be fully expanded (ie. not an environment variable).
120
121A different and possibly easier way is as follows:
122
123(1) Run Valgrind as normal, but add the flag --wait-for-gdb=yes.  This
124    puts the tool executable into a wait loop soon after it gains
125    control.  This delays startup for a few seconds.
126
127(2) In a different shell, do "gdb /proc/<pid>/exe <pid>", where
128    <pid> you read from the output printed by (1).  This attaches
129    GDB to the tool executable, which should be in the abovementioned
130    wait loop.
131
132(3) Do "cont" to continue.  After the loop finishes spinning, startup
133    will continue as normal.  Note that comment (3) above re passing
134    signals applies here too.
135
136
137Self-hosting
138~~~~~~~~~~~~
139To run Valgrind under Valgrind:
140
141(1) Check out 2 trees, "Inner" and "Outer".  Inner runs the app
142    directly.  Outer runs Inner.
143
144(2) Configure inner with --enable-inner and build/install as
145    usual.
146
147(3) Configure Outer normally and build/install as usual.
148
149(4) Choose a very simple program (date) and try
150
151    outer/.../bin/valgrind --sim-hints=enable-outer --trace-children=yes  \
152       --tool=cachegrind -v inner/.../bin/valgrind --tool=none -v prog
153
154If you omit the --trace-children=yes, you'll only monitor Inner's launcher
155program, not its stage2.
156
157The whole thing is fragile, confusing and slow, but it does work well enough
158for you to get some useful performance data.  Inner has most of
159its output (ie. those lines beginning with "==<pid>==") prefixed with a '>',
160which helps a lot.
161
162At the time of writing the allocator is not annotated with client requests
163so Memcheck is not as useful as it could be.  It also has not been tested
164much, so don't be surprised if you hit problems.
165
166When using self-hosting with an outer Callgrind tool, use '--pop-on-jump'
167(on the outer). Otherwise, Callgrind has much higher memory requirements. 
168
169
170Printing out problematic blocks
171~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
172If you want to print out a disassembly of a particular block that
173causes a crash, do the following.
174
175Try running with "--vex-guest-chase-thresh=0 --trace-flags=10000000
176--trace-notbelow=999999".  This should print one line for each block
177translated, and that includes the address.
178
179Then re-run with 999999 changed to the highest bb number shown.
180This will print the one line per block, and also will print a
181disassembly of the block in which the fault occurred.
182