* findvar.c (value_of_register): Mark the value as unavailable, if
	the register is unavailable.
	* frame.h (frame_register_unwind): New `unavailablep' parameter.
	(frame_register): New `unavailablep' parameter.
	(frame_register_read): Update comment.
	* frame.c (frame_register_unwind): New `unavailablep' parameter.
	Set it if the register is unavailable.  If the register is
	unavailable, clear the output buffer.
	(frame_register): New `unavailablep' parameter.  Pass it down.
	(frame_unwind_register): Adjust.
	(put_frame_register): Adjust.
	(frame_register_read): Adjust.  Also return false if the register
	is not available.
	(frame_register_unwind_location): Adjust.
	* sentinel-frame.c (sentinel_frame_prev_register): If the register
	is unavailable, mark the value accordingly.
	* stack.c (frame_info): Handle unavailable registers.

	gdb/testsuite/
	* gdb.trace/unavailable.exp (fpreg, spreg, pcreg): Define.
	(test_register, test_register_unavailable): New procedures.
	(gdb_unavailable_registers_test): New procedure.
	(gdb_trace_collection_test): Call it.
This commit is contained in:
Pedro Alves 2011-03-18 18:41:36 +00:00
parent e69aa73e27
commit 0fdb4f184b
8 changed files with 189 additions and 35 deletions

View File

@ -1,3 +1,23 @@
2011-03-18 Pedro Alves <pedro@codesourcery.com>
* findvar.c (value_of_register): Mark the value as unavailable, if
the register is unavailable.
* frame.h (frame_register_unwind): New `unavailablep' parameter.
(frame_register): New `unavailablep' parameter.
(frame_register_read): Update comment.
* frame.c (frame_register_unwind): New `unavailablep' parameter.
Set it if the register is unavailable. If the register is
unavailable, clear the output buffer.
(frame_register): New `unavailablep' parameter. Pass it down.
(frame_unwind_register): Adjust.
(put_frame_register): Adjust.
(frame_register_read): Adjust. Also return false if the register
is not available.
(frame_register_unwind_location): Adjust.
* sentinel-frame.c (sentinel_frame_prev_register): If the register
is unavailable, mark the value accordingly.
* stack.c (frame_info): Handle unavailable registers.
2011-03-18 Pedro Alves <pedro@codesourcery.com>
* mi/mi-main.c (register_changed_p): Handle REG_UNAVAILABLE, and

View File

@ -265,6 +265,7 @@ value_of_register (int regnum, struct frame_info *frame)
struct gdbarch *gdbarch = get_frame_arch (frame);
CORE_ADDR addr;
int optim;
int unavail;
struct value *reg_val;
int realnum;
gdb_byte raw_buffer[MAX_REGISTER_SIZE];
@ -276,16 +277,24 @@ value_of_register (int regnum, struct frame_info *frame)
+ gdbarch_num_pseudo_regs (gdbarch))
return value_of_user_reg (regnum, frame);
frame_register (frame, regnum, &optim, &lval, &addr, &realnum, raw_buffer);
frame_register (frame, regnum, &optim, &unavail,
&lval, &addr, &realnum, raw_buffer);
reg_val = allocate_value (register_type (gdbarch, regnum));
memcpy (value_contents_raw (reg_val), raw_buffer,
register_size (gdbarch, regnum));
if (!optim && !unavail)
memcpy (value_contents_raw (reg_val), raw_buffer,
register_size (gdbarch, regnum));
else
memset (value_contents_raw (reg_val), 0,
register_size (gdbarch, regnum));
VALUE_LVAL (reg_val) = lval;
set_value_address (reg_val, addr);
VALUE_REGNUM (reg_val) = regnum;
set_value_optimized_out (reg_val, optim);
if (unavail)
mark_value_bytes_unavailable (reg_val, 0, register_size (gdbarch, regnum));
VALUE_FRAME_ID (reg_val) = get_frame_id (frame);
return reg_val;
}

View File

@ -757,8 +757,9 @@ frame_pop (struct frame_info *this_frame)
void
frame_register_unwind (struct frame_info *frame, int regnum,
int *optimizedp, enum lval_type *lvalp,
CORE_ADDR *addrp, int *realnump, gdb_byte *bufferp)
int *optimizedp, int *unavailablep,
enum lval_type *lvalp, CORE_ADDR *addrp,
int *realnump, gdb_byte *bufferp)
{
struct value *value;
@ -775,13 +776,19 @@ frame_register_unwind (struct frame_info *frame, int regnum,
gdb_assert (value != NULL);
*optimizedp = value_optimized_out (value);
*unavailablep = !value_entirely_available (value);
*lvalp = VALUE_LVAL (value);
*addrp = value_address (value);
*realnump = VALUE_REGNUM (value);
if (bufferp && !*optimizedp)
memcpy (bufferp, value_contents_all (value),
TYPE_LENGTH (value_type (value)));
if (bufferp)
{
if (!*optimizedp && !*unavailablep)
memcpy (bufferp, value_contents_all (value),
TYPE_LENGTH (value_type (value)));
else
memset (bufferp, 0, TYPE_LENGTH (value_type (value)));
}
/* Dispose of the new value. This prevents watchpoints from
trying to watch the saved frame pointer. */
@ -791,7 +798,7 @@ frame_register_unwind (struct frame_info *frame, int regnum,
void
frame_register (struct frame_info *frame, int regnum,
int *optimizedp, enum lval_type *lvalp,
int *optimizedp, int *unavailablep, enum lval_type *lvalp,
CORE_ADDR *addrp, int *realnump, gdb_byte *bufferp)
{
/* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
@ -805,20 +812,21 @@ frame_register (struct frame_info *frame, int regnum,
/* Obtain the register value by unwinding the register from the next
(more inner frame). */
gdb_assert (frame != NULL && frame->next != NULL);
frame_register_unwind (frame->next, regnum, optimizedp, lvalp, addrp,
realnump, bufferp);
frame_register_unwind (frame->next, regnum, optimizedp, unavailablep,
lvalp, addrp, realnump, bufferp);
}
void
frame_unwind_register (struct frame_info *frame, int regnum, gdb_byte *buf)
{
int optimized;
int unavailable;
CORE_ADDR addr;
int realnum;
enum lval_type lval;
frame_register_unwind (frame, regnum, &optimized, &lval, &addr,
&realnum, buf);
frame_register_unwind (frame, regnum, &optimized, &unavailable,
&lval, &addr, &realnum, buf);
}
void
@ -940,10 +948,12 @@ put_frame_register (struct frame_info *frame, int regnum,
struct gdbarch *gdbarch = get_frame_arch (frame);
int realnum;
int optim;
int unavail;
enum lval_type lval;
CORE_ADDR addr;
frame_register (frame, regnum, &optim, &lval, &addr, &realnum, NULL);
frame_register (frame, regnum, &optim, &unavail,
&lval, &addr, &realnum, NULL);
if (optim)
error (_("Attempt to assign to a value that was optimized out."));
switch (lval)
@ -978,13 +988,15 @@ frame_register_read (struct frame_info *frame, int regnum,
gdb_byte *myaddr)
{
int optimized;
int unavailable;
enum lval_type lval;
CORE_ADDR addr;
int realnum;
frame_register (frame, regnum, &optimized, &lval, &addr, &realnum, myaddr);
frame_register (frame, regnum, &optimized, &unavailable,
&lval, &addr, &realnum, myaddr);
return !optimized;
return !optimized && !unavailable;
}
int
@ -1425,8 +1437,10 @@ frame_register_unwind_location (struct frame_info *this_frame, int regnum,
while (this_frame != NULL)
{
frame_register_unwind (this_frame, regnum, optimizedp, lvalp,
addrp, realnump, NULL);
int unavailable;
frame_register_unwind (this_frame, regnum, optimizedp, &unavailable,
lvalp, addrp, realnump, NULL);
if (*optimizedp)
break;

View File

@ -471,7 +471,8 @@ const char *frame_stop_reason_string (enum unwind_stop_reason);
fetch/compute the value. Instead just return the location of the
value. */
extern void frame_register_unwind (struct frame_info *frame, int regnum,
int *optimizedp, enum lval_type *lvalp,
int *optimizedp, int *unavailablep,
enum lval_type *lvalp,
CORE_ADDR *addrp, int *realnump,
gdb_byte *valuep);
@ -507,7 +508,8 @@ extern ULONGEST get_frame_register_unsigned (struct frame_info *frame,
VALUEP is NULL, the registers value is not fetched/computed. */
extern void frame_register (struct frame_info *frame, int regnum,
int *optimizedp, enum lval_type *lvalp,
int *optimizedp, int *unavailablep,
enum lval_type *lvalp,
CORE_ADDR *addrp, int *realnump,
gdb_byte *valuep);
@ -654,12 +656,14 @@ extern int deprecated_pc_in_call_dummy (struct gdbarch *gdbarch, CORE_ADDR pc);
/* FIXME: cagney/2003-02-02: Should be deprecated or replaced with a
function called get_frame_register_p(). This slightly weird (and
older) variant of get_frame_register() returns zero (indicating the
register is unavailable) if either: the register isn't cached; or
the register has been optimized out. Problem is, neither check is
exactly correct. A register can't be optimized out (it may not
have been saved as part of a function call); The fact that a
register isn't in the register cache doesn't mean that the register
isn't available (it could have been fetched from memory). */
register value is unavailable/invalid) if either: the register
isn't cached; or the register has been optimized out; or the
register contents are unavailable (because they haven't been
collected in a traceframe). Problem is, neither check is exactly
correct. A register can't be optimized out (it may not have been
saved as part of a function call); The fact that a register isn't
in the register cache doesn't mean that the register isn't
available (it could have been fetched from memory). */
extern int frame_register_read (struct frame_info *frame, int regnum,
gdb_byte *buf);

View File

@ -61,7 +61,10 @@ sentinel_frame_prev_register (struct frame_info *this_frame,
/* Use the regcache_cooked_read() method so that it, on the fly,
constructs either a raw or pseudo register from the raw
register cache. */
regcache_cooked_read (cache->regcache, regnum, value_contents_raw (value));
if (regcache_cooked_read (cache->regcache,
regnum,
value_contents_raw (value)) == REG_UNAVAILABLE)
mark_value_bytes_unavailable (value, 0, register_size (gdbarch, regnum));
return value;
}

View File

@ -1186,6 +1186,7 @@ frame_info (char *addr_exp, int from_tty)
{
enum lval_type lval;
int optimized;
int unavailable;
CORE_ADDR addr;
int realnum;
int count;
@ -1202,9 +1203,9 @@ frame_info (char *addr_exp, int from_tty)
/* Find out the location of the saved stack pointer with out
actually evaluating it. */
frame_register_unwind (fi, gdbarch_sp_regnum (gdbarch),
&optimized, &lval, &addr,
&optimized, &unavailable, &lval, &addr,
&realnum, NULL);
if (!optimized && lval == not_lval)
if (!optimized && !unavailable && lval == not_lval)
{
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
int sp_size = register_size (gdbarch, gdbarch_sp_regnum (gdbarch));
@ -1212,7 +1213,7 @@ frame_info (char *addr_exp, int from_tty)
CORE_ADDR sp;
frame_register_unwind (fi, gdbarch_sp_regnum (gdbarch),
&optimized, &lval, &addr,
&optimized, &unavailable, &lval, &addr,
&realnum, value);
/* NOTE: cagney/2003-05-22: This is assuming that the
stack pointer was packed as an unsigned integer. That
@ -1223,14 +1224,14 @@ frame_info (char *addr_exp, int from_tty)
printf_filtered ("\n");
need_nl = 0;
}
else if (!optimized && lval == lval_memory)
else if (!optimized && !unavailable && lval == lval_memory)
{
printf_filtered (" Previous frame's sp at ");
fputs_filtered (paddress (gdbarch, addr), gdb_stdout);
printf_filtered ("\n");
need_nl = 0;
}
else if (!optimized && lval == lval_register)
else if (!optimized && !unavailable && lval == lval_register)
{
printf_filtered (" Previous frame's sp in %s\n",
gdbarch_register_name (gdbarch, realnum));
@ -1248,11 +1249,11 @@ frame_info (char *addr_exp, int from_tty)
{
/* Find out the location of the saved register without
fetching the corresponding value. */
frame_register_unwind (fi, i, &optimized, &lval, &addr, &realnum,
NULL);
frame_register_unwind (fi, i, &optimized, &unavailable,
&lval, &addr, &realnum, NULL);
/* For moment, only display registers that were saved on the
stack. */
if (!optimized && lval == lval_memory)
if (!optimized && !unavailable && lval == lval_memory)
{
if (count == 0)
puts_filtered (" Saved registers:\n ");

View File

@ -1,3 +1,10 @@
2011-03-18 Pedro Alves <pedro@codesourcery.com>
* gdb.trace/unavailable.exp (fpreg, spreg, pcreg): Define.
(test_register, test_register_unavailable): New procedures.
(gdb_unavailable_registers_test): New procedure.
(gdb_trace_collection_test): Call it.
2011-03-18 Phil Muldoon <pmuldoon@redhat.com>
PR python/12149

View File

@ -30,10 +30,48 @@ if { [gdb_compile "$srcdir/$subdir/$srcfile" $binfile \
set ws "\[\r\n\t \]+"
set cr "\[\r\n\]+"
if [istarget "x86_64-*"] then {
set fpreg "rbp"
set spreg "rsp"
set pcreg "rip"
} elseif [istarget "i?86-*"] then {
set fpreg "ebp"
set spreg "esp"
set pcreg "eip"
} else {
set fpreg "fp"
set spreg "sp"
set pcreg "pc"
}
#
# Utility procs
#
proc test_register { reg } {
global gdb_prompt
global hex
global cr
gdb_test_multiple "print /x $reg" "collected $reg" {
-re "\\$\[0-9\]+ = \[x0\]+$cr$gdb_prompt $" {
fail "collected $reg (zero)"
}
-re "\\$\[0-9\]+ = $hex$cr$gdb_prompt $" {
pass "collected $reg"
}
-re "\[Ee\]rror.*$gdb_prompt $" {
fail "collected $reg (error)"
}
}
}
proc test_register_unavailable { reg } {
gdb_test "print /x $reg" \
"<unavailable>" \
"correctly report $reg as unavailable"
}
proc prepare_for_trace_test {} {
global executable
@ -69,6 +107,63 @@ proc run_trace_experiment { test_func } {
# Test procs
#
proc gdb_unavailable_registers_test { } {
global gdb_prompt
global spreg
global pcreg
global pf_prefix
set old_pf_prefix $pf_prefix
set pf_prefix "$pf_prefix unavailable registers:"
prepare_for_trace_test
# We'll simply re-use the globals_test_function for this test
gdb_test "trace globals_test_func" \
"Tracepoint \[0-9\]+ at .*" \
"set tracepoint"
# Collect nothing.
# Begin the test.
run_trace_experiment globals_test_func
# On some archs, the $sp/$pc are a real raw registers. On others,
# like x86, they're user registers. Test both variants.
test_register_unavailable "\$$spreg"
test_register_unavailable "\$sp"
# Test reading uncollected pseudo-registers. The set of which
# depends on target.
if [istarget "x86_64-*"] then {
# Check the raw register first.
test_register_unavailable "\$rax"
test_register_unavailable "\$eax"
test_register_unavailable "\$ax"
} elseif [istarget "i?86-*"] then {
# Check the raw register first.
test_register_unavailable "\$eax"
test_register_unavailable "\$ax"
}
# GDBserver always provides the PC value of regular tracepoint
# hits, since it's the same as the tracepoint's address.
test_register "\$$pcreg"
test_register "\$pc"
gdb_test "info registers" \
"\\*value not available\\*.*\\*value not available\\*" \
"info registers, multiple registers not available"
gdb_test "info registers \$$spreg" \
"\\*value not available\\*" \
"info registers \$$spreg reports not available"
gdb_test "tfind none" "#0 end .*" "cease trace debugging"
set pf_prefix $old_pf_prefix
}
proc gdb_collect_globals_test { } {
global ws
global cr
@ -321,6 +416,7 @@ proc gdb_collect_globals_test { } {
proc gdb_trace_collection_test {} {
gdb_collect_globals_test
gdb_unavailable_registers_test
}
clean_restart $executable