/* An instruction instrumented for gdbserver looks like this:
1. Ist_Mark (0x1234)
- 2. helperc_CallDebugger (0x1234)
+ 2. Put (IP, 0x1234)
+ 3. helperc_CallDebugger (0x1234)
This will give control to gdb if there is a break at 0x1234
or if we are single stepping
- 3. ... here the real IR for the instruction at 0x1234
+ 4. ... here the real IR for the instruction at 0x1234
When there is a break at 0x1234:
if user does "continue" or "step" or similar,
single stepping (kind == GS_jump).
When gdbserver is not single stepping anymore, all GS_jump entries
are removed, their translations are invalidated.
+
+ Note for ARM: addr in GS_Address is the value without the thumb bit set.
*/
static VgHashTable gs_addresses = NULL;
+// Transform addr in the form stored in the list of addresses.
+// For the ARM architecture, we store it with the thumb bit set to 0.
+static Addr HT_addr ( Addr addr )
+{
+#if defined(VGA_arm)
+ return addr & ~(Addr)1;
+#else
+ return addr;
+#endif
+}
+
static void add_gs_address (Addr addr, GS_Kind kind, char* from)
{
GS_Address *p;
p = VG_(arena_malloc)(VG_AR_CORE, from, sizeof(GS_Address));
- p->addr = addr;
+ p->addr = HT_addr (addr);
p->kind = kind;
VG_(HT_add_node)(gs_addresses, p);
- VG_(discard_translations) (addr, 1, from);
+ /* It should be sufficient to discard a range of 1.
+ We use 2 to ensure the below is not sensitive to the presence
+ of thumb bit in the range of addresses to discard. */
+ VG_(discard_translations) (addr, 2, from);
}
static void remove_gs_address (GS_Address* g, char* from)
{
VG_(HT_remove) (gs_addresses, g->addr);
- VG_(discard_translations) (g->addr, 1, from);
+ // See add_gs_address for the explanation for the range 2 below.
+ VG_(discard_translations) (g->addr, 2, from);
VG_(arena_free) (VG_AR_CORE, g);
}
{
GS_Address *g;
- g = VG_(HT_lookup) (gs_addresses, (UWord)addr);
+ g = VG_(HT_lookup) (gs_addresses, (UWord)HT_addr(addr));
if (insert) {
/* insert a breakpoint at addr or upgrade its kind */
if (g == NULL) {
VG_(HT_ResetIter) (gs_addresses);
while ((g = VG_(HT_Next) (gs_addresses))) {
for (e = 0; e < vge->n_used; e++) {
- if (g->addr >= vge->base[e] && g->addr < vge->base[e] + vge->len[e]) {
+ if (g->addr >= HT_addr(vge->base[e])
+ && g->addr < HT_addr(vge->base[e]) + vge->len[e]) {
dlog(2,
"gdbserver_instrumentation_needed %p %s reason %s\n",
C2v(g->addr), sym(g->addr, /* is_code */ True),
static void invalidate_if_jump_not_yet_gdbserved (Addr addr, char* from)
{
- if (VG_(HT_lookup) (gs_addresses, (UWord)addr))
+ if (VG_(HT_lookup) (gs_addresses, (UWord)HT_addr(addr)))
return;
add_gs_address (addr, GS_jump, from);
}
return;
if (valgrind_single_stepping() ||
- ((g = VG_(HT_lookup) (gs_addresses, (UWord)iaddr)) &&
+ ((g = VG_(HT_lookup) (gs_addresses, (UWord)HT_addr(iaddr))) &&
(g->kind == GS_break))) {
- if (iaddr == ignore_this_break_once) {
+ if (iaddr == HT_addr(ignore_this_break_once)) {
dlog(1, "ignoring ignore_this_break_once %s\n",
sym(ignore_this_break_once, /* is_code */ True));
ignore_this_break_once = 0;
VexGuestLayout* layout,
VexGuestExtents* vge,
IRType gWordTy, IRType hWordTy,
- Addr iaddr, /* Addr of instruction being instrumented */
+ Addr iaddr, /* Addr of instruction being instrumented */
+ UChar delta, /* delta to add to iaddr to obtain IP */
IRSB* irsb) /* irsb block to which call is added */
{
void* fn;
remove the redundant store. And in any case, when debugging a
piece of code, the efficiency requirement is not critical: very
few blocks will be instrumented for debugging. */
-
- addStmtToIRSB(irsb, IRStmt_Put(layout->offset_IP , mkIRExpr_HWord(iaddr)));
+
+ /* For platforms on which the IP can differ from the addr of the instruction
+ being executed, we need to add the delta to obtain the IP.
+ This IP will be given to gdb (e.g. if a breakpoint is put at iaddr).
+
+ For ARM, this delta will ensure that the thumb bit is set in the
+ IP when executing thumb code. gdb uses this thumb bit a.o.
+ to properly guess the next IP for the 'step' and 'stepi' commands. */
+ vg_assert(delta <= 1);
+ addStmtToIRSB(irsb, IRStmt_Put(layout->offset_IP ,
+ mkIRExpr_HWord(iaddr + (Addr)delta)));
fn = &VG_(helperc_CallDebugger);
nm = "VG_(helperc_CallDebugger)";
VG_(add_stmt_call_gdbserver) ( sb_in, layout, vge,
gWordTy, hWordTy,
st->Ist.IMark.addr,
+ st->Ist.IMark.delta,
sb_out);
/* There is an optimisation possible here for Vg_VgdbFull:
Put a guard ensuring we only call gdbserver if 'FullCallNeeded'.
will report an error message when using the target
command. Debugging will not work because gdb will then not be
able to fetch the registers from the Valgrind gdbserver.
+ For ARM programs using the thumb instruction set, you must use
+ a gdb version >= 7.1 as previous versions have problems
+ with next/step/breakpoints/... in thumb code.
</para>
</listitem>
# a location in the nptl lib rather than our sources (same as
# standard gdb gdbserver) gdb 7.0
# same special transform but for gdb 7.2
+# transform info thread of 7.3 into the layout of 7.2 and before.
# delete lines telling that some memory can't be accessed: this is
# a.o. produced by gdb 7.2 on arm (same with standard gdbserver)
# delete empty lines (the last line (only made of prompts) sometimes
-e 's/pid [0-9][0-9]*/pid ..../g' \
-e 's/Thread [0-9][0-9]*/Thread ..../g' \
-e '/\[Switching to Thread ....\]/d' \
+ -e 's/\(\[Switching to thread [1234] (Thread ....)\]\)#0/\1\n#0/' \
-e 's/^\([ \* ] [0-9] Thread .... (tid [0-9] VgTs_WaitSys) 0x........ in\).*$/\1 syscall .../' \
-e 's/#[0-9]\( 0x........ in sleeper_or_burner\)/#.\1/' \
-e '/^Reading symbols from .*\.\.\.done\./d' \
-e 's/0x........ in \(main (argc=1, argv=0x........) at watchpoints.c:[24][3689]\)/\1/' \
-e 's/0x........ in \(main () at clean_after_fork.c:32\)/\1/' \
-e 's/^0x........ in \*__GI_raise (sig=8).*/0x........ in test4 () at faultstatus.c:120\n120 volatile int v = 44\/zero();/' \
+ -e 's/^0x........ in raise (.*/0x........ in test4 () at faultstatus.c:120\n120 volatile int v = 44\/zero();/' \
-e '/ at ..\/nptl\/sysdeps\/unix\/sysv\/linux\/raise.c:[0-9]*/d' \
- -e '/ in ..\/nptl\/sysdeps\/unix\/sysv\/linux\/raise.c/d' \
+ -e '/ in ..\/nptl\/sysdeps\/unix\/sysv\/linux\/.*raise.c/d' \
-e 's/^0x........ in \.\{0,1\}raise () from \/lib[0-9]\{0,2\}\/libc\.so\../0x........ in test4 () at faultstatus.c:120\n120 volatile int v = 44\/zero();'/ \
+ -e '/Id Target Id Frame/d' \
+ -e 's/^\([ \*] [1234] \) *Thread /\1Thread /' \
+ -e 's/VgTs_WaitSys) 0x/VgTs_WaitSys) 0x/' \
-e '/Cannot access memory at address 0x......../d' \
-e '/^$/d' |
awk '{ if ( ($1 >= 7) || (($1 == 6) && ($2 >= 5)) ) print "version ok"}'`
if [ "$VERSIONOK" = "" ]
then
- echo "gdbserver tests suppressed as $1 version is not >= 6.5: " $VERSIONLINE
- rm gdbserver_tests/gdb
+ echo "gdbserver tests suppressed as $1 version is < 6.5: " $VERSIONLINE
+ rm -f gdbserver_tests/gdb
+ fi
+
+ # We need at least a 7.1 version on ARM to run tests doing step/next/...
+ # (gdb 7.0 has bugs in the 'guess next pc' heuristic in thumb mode).
+ if tests/arch_test arm
+ then
+ VERSIONOK=`echo $VERSION |
+ awk '{ if ( ($1 >= 8) || (($1 == 7) && ($2 >= 1)) ) print "version ok"}'`
+ if [ "$VERSIONOK" = "" ]
+ then
+ echo "gdbserver 'step/next' tests suppressed as arm $1 version is < 7.1: " $VERSIONLINE
+ rm -f gdbserver_tests/gdb.step
+ else
+ touch gdbserver_tests/gdb.step
+ fi
+ else
+ touch gdbserver_tests/gdb.step
fi
# We need at least a 7.2 version for gdb tests using eval command
awk '{ if ( ($1 >= 8) || (($1 == 7) && ($2 >= 2)) ) print "version ok"}'`
if [ "$VERSIONOK" = "" ]
then
- echo "gdbserver eval tests suppressed as $1 version is not >= 7.2: " $VERSIONLINE
+ echo "gdbserver eval tests suppressed as $1 version is < 7.2: " $VERSIONLINE
rm -f gdbserver_tests/gdb.eval
else
touch gdbserver_tests/gdb.eval
# test execution control (break, next, step) and inferior calls
# when stopped on these events
-prereq: test -e gdb
+prereq: test -e gdb -a -f gdb.step
prog: t
vgopts: --tool=memcheck --vgdb=yes --vgdb-error=0 --vgdb-prefix=./vgdb-prefix-mcbreak
stdout_filter: filter_gdb
Program received signal SIGTRAP, Trace/breakpoint trap.
0x........ in do_burn () at sleepers.c:39
39 for (i = 0; i < burn; i++) loopnr++;
-[Switching to thread 1 (Thread ....)]#0 0x........ in do_burn () at sleepers.c:39
+[Switching to thread 1 (Thread ....)]
+#0 0x........ in do_burn () at sleepers.c:39
39 for (i = 0; i < burn; i++) loopnr++;
$1 = void
-[Switching to thread 2 (Thread ....)]#0 0x........ in syscall ...
+[Switching to thread 2 (Thread ....)]
+#0 0x........ in syscall ...
Could not write register "xxx"; remote failure reply 'E.
ERROR changing register xxx regno y
gdb commands changing registers (pc, sp, ...) (e.g. 'jump',
can only be accepted if the thread is VgTs_Runnable or VgTs_Yielding state
Thread status is VgTs_WaitSys
'
-[Switching to thread 3 (Thread ....)]#0 0x........ in syscall ...
+[Switching to thread 3 (Thread ....)]
+#0 0x........ in syscall ...
Could not write register "xxx"; remote failure reply 'E.
ERROR changing register xxx regno y
gdb commands changing registers (pc, sp, ...) (e.g. 'jump',
can only be accepted if the thread is VgTs_Runnable or VgTs_Yielding state
Thread status is VgTs_WaitSys
'
-[Switching to thread 4 (Thread ....)]#0 0x........ in syscall ...
+[Switching to thread 4 (Thread ....)]
+#0 0x........ in syscall ...
Could not write register "xxx"; remote failure reply 'E.
ERROR changing register xxx regno y
gdb commands changing registers (pc, sp, ...) (e.g. 'jump',
# but this introduces too much dependencies to scheduler fairness.
args: 100 100000000 1000000000 -S-S-SB-
vgopts: --tool=memcheck --vgdb=yes --vgdb-error=0 --vgdb-prefix=./vgdb-prefix-mcinfcallWSRU
+# We need a non buggy gdb.step on arm thumb.
# Disable on Darwin: inferior call rejected as it cannot find malloc.
-prereq: test -e gdb && ../tests/os_test linux
+prereq: test -e gdb -a -f gdb.step && ../tests/os_test linux
# filter_gdb to replace pid and Thread numbers in the output of the program:
stderr_filter: filter_gdb
progB: gdb
# test the memcheck watchpoint functionality
# Note: we need --vgdb=full to stop at the instruction following the watchpoint.
-prereq: test -e gdb
+# We need a non buggy gdb.step as watchpoints are placed after a "step".
+prereq: test -e gdb -a -f gdb.step
prog: watchpoints
vgopts: --tool=memcheck --vgdb=full --vgdb-error=0 --vgdb-prefix=./vgdb-prefix-mcwatchpoints
stdout_filter: filter_make_empty
projects / thirdparty / valgrind.git / commitdiff
