old-cross-binutils/gdb/tracefile.c
Tom Tromey ac29888840 Remove some variables but call functions for side effects
This patch consolidates the (possibly-questionable) spots where we
remove a declaration but continue to call some function for side
effects.  In a couple of cases it wasn't entirely clear to me that
this mattered; and in some other cases it might be more aesthetically
pleasing to use ATTRIBUTE_UNUSED.  So, I broke this out into a
separate patch for simpler review.

2016-07-14  Tom Tromey  <tom@tromey.com>

	* arch-utils.c (default_skip_permanent_breakpoint): Remove
	"bp_insn".
	* disasm.c (do_assembly_only): Remove "num_displayed".
	* dwarf2read.c (read_abbrev_offset): Remove "length".
	(dwarf_decode_macro_bytes) <DW_MACINFO_vendor_ext>: Remove
	"constant".
	* m32c-tdep.c (make_regs): Remove "r2hl", "r3hl", and "intbhl".
	* microblaze-tdep.c (microblaze_frame_cache): Remove "func".
	* tracefile.c (trace_save): Remove "status".
2016-07-14 10:35:40 -06:00

508 lines
14 KiB
C

/* Trace file support in GDB.
Copyright (C) 1997-2016 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "tracefile.h"
#include "ctf.h"
#include "exec.h"
#include "regcache.h"
/* Helper macros. */
#define TRACE_WRITE_R_BLOCK(writer, buf, size) \
writer->ops->frame_ops->write_r_block ((writer), (buf), (size))
#define TRACE_WRITE_M_BLOCK_HEADER(writer, addr, size) \
writer->ops->frame_ops->write_m_block_header ((writer), (addr), \
(size))
#define TRACE_WRITE_M_BLOCK_MEMORY(writer, buf, size) \
writer->ops->frame_ops->write_m_block_memory ((writer), (buf), \
(size))
#define TRACE_WRITE_V_BLOCK(writer, num, val) \
writer->ops->frame_ops->write_v_block ((writer), (num), (val))
/* Free trace file writer. */
static void
trace_file_writer_xfree (void *arg)
{
struct trace_file_writer *writer = (struct trace_file_writer *) arg;
writer->ops->dtor (writer);
xfree (writer);
}
/* Save tracepoint data to file named FILENAME through WRITER. WRITER
determines the trace file format. If TARGET_DOES_SAVE is non-zero,
the save is performed on the target, otherwise GDB obtains all trace
data and saves it locally. */
static void
trace_save (const char *filename, struct trace_file_writer *writer,
int target_does_save)
{
struct trace_status *ts = current_trace_status ();
struct uploaded_tp *uploaded_tps = NULL, *utp;
struct uploaded_tsv *uploaded_tsvs = NULL, *utsv;
ULONGEST offset = 0;
#define MAX_TRACE_UPLOAD 2000
gdb_byte buf[MAX_TRACE_UPLOAD];
enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ());
/* If the target is to save the data to a file on its own, then just
send the command and be done with it. */
if (target_does_save)
{
if (!writer->ops->target_save (writer, filename))
error (_("Target failed to save trace data to '%s'."),
filename);
return;
}
/* Get the trace status first before opening the file, so if the
target is losing, we can get out without touching files. Since
we're just calling this for side effects, we ignore the
result. */
target_get_trace_status (ts);
writer->ops->start (writer, filename);
writer->ops->write_header (writer);
/* Write descriptive info. */
/* Write out the size of a register block. */
writer->ops->write_regblock_type (writer, trace_regblock_size);
/* Write out the target description info. */
writer->ops->write_tdesc (writer);
/* Write out status of the tracing run (aka "tstatus" info). */
writer->ops->write_status (writer, ts);
/* Note that we want to upload tracepoints and save those, rather
than simply writing out the local ones, because the user may have
changed tracepoints in GDB in preparation for a future tracing
run, or maybe just mass-deleted all types of breakpoints as part
of cleaning up. So as not to contaminate the session, leave the
data in its uploaded form, don't make into real tracepoints. */
/* Get trace state variables first, they may be checked when parsing
uploaded commands. */
target_upload_trace_state_variables (&uploaded_tsvs);
for (utsv = uploaded_tsvs; utsv; utsv = utsv->next)
writer->ops->write_uploaded_tsv (writer, utsv);
free_uploaded_tsvs (&uploaded_tsvs);
target_upload_tracepoints (&uploaded_tps);
for (utp = uploaded_tps; utp; utp = utp->next)
target_get_tracepoint_status (NULL, utp);
for (utp = uploaded_tps; utp; utp = utp->next)
writer->ops->write_uploaded_tp (writer, utp);
free_uploaded_tps (&uploaded_tps);
/* Mark the end of the definition section. */
writer->ops->write_definition_end (writer);
/* Get and write the trace data proper. */
while (1)
{
LONGEST gotten = 0;
/* The writer supports writing the contents of trace buffer
directly to trace file. Don't parse the contents of trace
buffer. */
if (writer->ops->write_trace_buffer != NULL)
{
/* We ask for big blocks, in the hopes of efficiency, but
will take less if the target has packet size limitations
or some such. */
gotten = target_get_raw_trace_data (buf, offset,
MAX_TRACE_UPLOAD);
if (gotten < 0)
error (_("Failure to get requested trace buffer data"));
/* No more data is forthcoming, we're done. */
if (gotten == 0)
break;
writer->ops->write_trace_buffer (writer, buf, gotten);
offset += gotten;
}
else
{
uint16_t tp_num;
uint32_t tf_size;
/* Parse the trace buffers according to how data are stored
in trace buffer in GDBserver. */
gotten = target_get_raw_trace_data (buf, offset, 6);
if (gotten == 0)
break;
/* Read the first six bytes in, which is the tracepoint
number and trace frame size. */
tp_num = (uint16_t)
extract_unsigned_integer (&buf[0], 2, byte_order);
tf_size = (uint32_t)
extract_unsigned_integer (&buf[2], 4, byte_order);
writer->ops->frame_ops->start (writer, tp_num);
gotten = 6;
if (tf_size > 0)
{
unsigned int block;
offset += 6;
for (block = 0; block < tf_size; )
{
gdb_byte block_type;
/* We'll fetch one block each time, in order to
handle the extremely large 'M' block. We first
fetch one byte to get the type of the block. */
gotten = target_get_raw_trace_data (buf, offset, 1);
if (gotten < 1)
error (_("Failure to get requested trace buffer data"));
gotten = 1;
block += 1;
offset += 1;
block_type = buf[0];
switch (block_type)
{
case 'R':
gotten
= target_get_raw_trace_data (buf, offset,
trace_regblock_size);
if (gotten < trace_regblock_size)
error (_("Failure to get requested trace"
" buffer data"));
TRACE_WRITE_R_BLOCK (writer, buf,
trace_regblock_size);
break;
case 'M':
{
unsigned short mlen;
ULONGEST addr;
LONGEST t;
int j;
t = target_get_raw_trace_data (buf,offset, 10);
if (t < 10)
error (_("Failure to get requested trace"
" buffer data"));
offset += 10;
block += 10;
gotten = 0;
addr = (ULONGEST)
extract_unsigned_integer (buf, 8,
byte_order);
mlen = (unsigned short)
extract_unsigned_integer (&buf[8], 2,
byte_order);
TRACE_WRITE_M_BLOCK_HEADER (writer, addr,
mlen);
/* The memory contents in 'M' block may be
very large. Fetch the data from the target
and write them into file one by one. */
for (j = 0; j < mlen; )
{
unsigned int read_length;
if (mlen - j > MAX_TRACE_UPLOAD)
read_length = MAX_TRACE_UPLOAD;
else
read_length = mlen - j;
t = target_get_raw_trace_data (buf,
offset + j,
read_length);
if (t < read_length)
error (_("Failure to get requested"
" trace buffer data"));
TRACE_WRITE_M_BLOCK_MEMORY (writer, buf,
read_length);
j += read_length;
gotten += read_length;
}
break;
}
case 'V':
{
int vnum;
LONGEST val;
gotten
= target_get_raw_trace_data (buf, offset,
12);
if (gotten < 12)
error (_("Failure to get requested"
" trace buffer data"));
vnum = (int) extract_signed_integer (buf,
4,
byte_order);
val
= extract_signed_integer (&buf[4], 8,
byte_order);
TRACE_WRITE_V_BLOCK (writer, vnum, val);
}
break;
default:
error (_("Unknown block type '%c' (0x%x) in"
" trace frame"),
block_type, block_type);
}
block += gotten;
offset += gotten;
}
}
else
offset += gotten;
writer->ops->frame_ops->end (writer);
}
}
writer->ops->end (writer);
}
static void
trace_save_command (char *args, int from_tty)
{
int target_does_save = 0;
char **argv;
char *filename = NULL;
struct cleanup *back_to;
int generate_ctf = 0;
struct trace_file_writer *writer = NULL;
if (args == NULL)
error_no_arg (_("file in which to save trace data"));
argv = gdb_buildargv (args);
back_to = make_cleanup_freeargv (argv);
for (; *argv; ++argv)
{
if (strcmp (*argv, "-r") == 0)
target_does_save = 1;
if (strcmp (*argv, "-ctf") == 0)
generate_ctf = 1;
else if (**argv == '-')
error (_("unknown option `%s'"), *argv);
else
filename = *argv;
}
if (!filename)
error_no_arg (_("file in which to save trace data"));
if (generate_ctf)
writer = ctf_trace_file_writer_new ();
else
writer = tfile_trace_file_writer_new ();
make_cleanup (trace_file_writer_xfree, writer);
trace_save (filename, writer, target_does_save);
if (from_tty)
printf_filtered (_("Trace data saved to %s '%s'.\n"),
generate_ctf ? "directory" : "file", filename);
do_cleanups (back_to);
}
/* Save the trace data to file FILENAME of tfile format. */
void
trace_save_tfile (const char *filename, int target_does_save)
{
struct trace_file_writer *writer;
struct cleanup *back_to;
writer = tfile_trace_file_writer_new ();
back_to = make_cleanup (trace_file_writer_xfree, writer);
trace_save (filename, writer, target_does_save);
do_cleanups (back_to);
}
/* Save the trace data to dir DIRNAME of ctf format. */
void
trace_save_ctf (const char *dirname, int target_does_save)
{
struct trace_file_writer *writer;
struct cleanup *back_to;
writer = ctf_trace_file_writer_new ();
back_to = make_cleanup (trace_file_writer_xfree, writer);
trace_save (dirname, writer, target_does_save);
do_cleanups (back_to);
}
/* Fetch register data from tracefile, shared for both tfile and
ctf. */
void
tracefile_fetch_registers (struct regcache *regcache, int regno)
{
struct gdbarch *gdbarch = get_regcache_arch (regcache);
struct tracepoint *tp = get_tracepoint (get_tracepoint_number ());
int regn;
/* We get here if no register data has been found. Mark registers
as unavailable. */
for (regn = 0; regn < gdbarch_num_regs (gdbarch); regn++)
regcache_raw_supply (regcache, regn, NULL);
/* We can often usefully guess that the PC is going to be the same
as the address of the tracepoint. */
if (tp == NULL || tp->base.loc == NULL)
return;
/* But don't try to guess if tracepoint is multi-location... */
if (tp->base.loc->next)
{
warning (_("Tracepoint %d has multiple "
"locations, cannot infer $pc"),
tp->base.number);
return;
}
/* ... or does while-stepping. */
else if (tp->step_count > 0)
{
warning (_("Tracepoint %d does while-stepping, "
"cannot infer $pc"),
tp->base.number);
return;
}
/* Guess what we can from the tracepoint location. */
gdbarch_guess_tracepoint_registers (gdbarch, regcache,
tp->base.loc->address);
}
/* This is the implementation of target_ops method to_has_all_memory. */
static int
tracefile_has_all_memory (struct target_ops *ops)
{
return 1;
}
/* This is the implementation of target_ops method to_has_memory. */
static int
tracefile_has_memory (struct target_ops *ops)
{
return 1;
}
/* This is the implementation of target_ops method to_has_stack.
The target has a stack when GDB has already selected one trace
frame. */
static int
tracefile_has_stack (struct target_ops *ops)
{
return get_traceframe_number () != -1;
}
/* This is the implementation of target_ops method to_has_registers.
The target has registers when GDB has already selected one trace
frame. */
static int
tracefile_has_registers (struct target_ops *ops)
{
return get_traceframe_number () != -1;
}
/* This is the implementation of target_ops method to_thread_alive.
tracefile has one thread faked by GDB. */
static int
tracefile_thread_alive (struct target_ops *ops, ptid_t ptid)
{
return 1;
}
/* This is the implementation of target_ops method to_get_trace_status.
The trace status for a file is that tracing can never be run. */
static int
tracefile_get_trace_status (struct target_ops *self, struct trace_status *ts)
{
/* Other bits of trace status were collected as part of opening the
trace files, so nothing to do here. */
return -1;
}
/* Initialize OPS for tracefile related targets. */
void
init_tracefile_ops (struct target_ops *ops)
{
ops->to_stratum = process_stratum;
ops->to_get_trace_status = tracefile_get_trace_status;
ops->to_has_all_memory = tracefile_has_all_memory;
ops->to_has_memory = tracefile_has_memory;
ops->to_has_stack = tracefile_has_stack;
ops->to_has_registers = tracefile_has_registers;
ops->to_thread_alive = tracefile_thread_alive;
ops->to_magic = OPS_MAGIC;
}
extern initialize_file_ftype _initialize_tracefile;
void
_initialize_tracefile (void)
{
add_com ("tsave", class_trace, trace_save_command, _("\
Save the trace data to a file.\n\
Use the '-ctf' option to save the data to CTF format.\n\
Use the '-r' option to direct the target to save directly to the file,\n\
using its own filesystem."));
}