gdb/gdbserver/

2010-06-01  Pedro Alves  <pedro@codesourcery.com>
	    Stan Shebs  <stan@codesourcery.com>

	* Makefile.in (IPA_DEPFILES, extra_libraries): New.
	(all): Depend on $(extra_libraries).
	(install-only): Install the IPA.
	(IPA_OBJS, IPA_LIB): New.
	(clean): Remove the IPA lib.
	(IPAGENT_CFLAGS): New.
	(tracepoint-ipa.o, utils-ipa.o, remote-utils-ipa.o)
	(regcache-ipa.o, i386-linux-ipa.o, linux-i386-ipa.o)
	(linux-amd64-ipa.o, amd64-linux-ipa.o): New rules.
	* linux-amd64-ipa.c, linux-i386-ipa.c: New files.
	* configure.ac: Check for atomic builtins support in the compiler.
	(IPA_DEPFILES, extra_libraries): Define.
	* configure.srv (ipa_obj): Add description.
	(ipa_i386_linux_regobj, ipa_amd64_linux_regobj): Define.
	(i[34567]86-*-linux*): Set ipa_obj.
	(x86_64-*-linux*): Set ipa_obj.
	* linux-low.c (stabilizing_threads): New.
	(supports_fast_tracepoints): New.
	(linux_detach): Stabilize threads before detaching.
	(handle_tracepoints): Handle internal tracing breakpoints.  Assert
	the lwp is either not stabilizing, or is moving out of a jump pad.
	(linux_fast_tracepoint_collecting): New.
	(maybe_move_out_of_jump_pad): New.
	(enqueue_one_deferred_signal): New.
	(dequeue_one_deferred_signal): New.
	(linux_wait_for_event_1): If moving out of a jump pad, defer
	pending signals to later.
	(linux_stabilize_threads): New.
	(linux_wait_1): Check if threads need moving out of jump pads, and
	do it if so.
	(stuck_in_jump_pad_callback): New.
	(move_out_of_jump_pad_callback): New.
	(lwp_running): New.
	(linux_resume_one_lwp): Handle moving out of jump pads.
	(linux_set_resume_request): Dequeue deferred signals.
	(need_step_over_p): Also step over fast tracepoint jumps.
	(start_step_over): Also uninsert fast tracepoint jumps.
	(finish_step_over): Also reinsert fast tracepoint jumps.
	(linux_install_fast_tracepoint_jump): New.
	(linux_target_ops): Install linux_stabilize_threads and
	linux_install_fast_tracepoint_jump_pad.
	* linux-low.h (linux_target_ops) <get_thread_area,
	install_fast_tracepoint_jump_pad>: New fields.
	(struct lwp_info) <collecting_fast_tracepoint,
	pending_signals_to_report, exit_jump_pad_bkpt>: New fields.
	(linux_get_thread_area): Declare.
	* linux-x86-low.c (jump_insn): New.
	(x86_get_thread_area): New.
	(append_insns): New.
	(push_opcode): New.
	(amd64_install_fast_tracepoint_jump_pad): New.
	(i386_install_fast_tracepoint_jump_pad): New.
	(x86_install_fast_tracepoint_jump_pad): New.
	(the_low_target): Install x86_get_thread_area and
	x86_install_fast_tracepoint_jump_pad.
	* mem-break.c (set_raw_breakpoint_at): Use read_inferior_memory.
	(struct fast_tracepoint_jump): New.
	(fast_tracepoint_jump_insn): New.
	(fast_tracepoint_jump_shadow): New.
	(find_fast_tracepoint_jump_at): New.
	(fast_tracepoint_jump_here): New.
	(delete_fast_tracepoint_jump): New.
	(set_fast_tracepoint_jump): New.
	(uninsert_fast_tracepoint_jumps_at): New.
	(reinsert_fast_tracepoint_jumps_at): New.
	(set_breakpoint_at): Use write_inferior_memory.
	(uninsert_raw_breakpoint): Use write_inferior_memory.
	(check_mem_read): Mask out fast tracepoint jumps.
	(check_mem_write): Mask out fast tracepoint jumps.
	* mem-break.h (struct fast_tracepoint_jump): Forward declare.
	(set_fast_tracepoint_jump): Declare.
	(delete_fast_tracepoint_jump)
	(fast_tracepoint_jump_here, uninsert_fast_tracepoint_jumps_at)
	(reinsert_fast_tracepoint_jumps_at): Declare.
	* regcache.c: Don't compile many functions when building the
	in-process agent library.
	(init_register_cache) [IN_PROCESS_AGENT]: Don't allow allocating
	the register buffer in the heap.
	(free_register_cache): If the register buffer isn't owned by the
	regcache, don't free it.
	(set_register_cache) [IN_PROCESS_AGENT]: Don't re-alocate
	pre-existing register caches.
	* remote-utils.c (convert_int_to_ascii): Constify `from' parameter
	type.
	(convert_ascii_to_int): : Constify `from' parameter type.
	(decode_M_packet, decode_X_packet): Replace the `to' parameter by
	a `to_p' pointer to pointer parameter.  If TO_P is NULL, malloc
	the needed buffer in-place.
	(relocate_instruction): New.
	* server.c (handle_query) <qSymbols>: If the target supports
	tracepoints, give it a chance of looking up symbols.  Report
	support for fast tracepoints.
	(handle_status): Stabilize threads.
	(process_serial_event): Adjust.
	* server.h (struct fast_tracepoint_jump): Forward declare.
	(struct process_info) <fast_tracepoint_jumps>: New field.
	(convert_ascii_to_int, convert_int_to_ascii): Adjust.
	(decode_X_packet, decode_M_packet): Adjust.
	(relocate_instruction): Declare.
	(in_process_agent_loaded): Declare.
	(tracepoint_look_up_symbols): Declare.
	(struct fast_tpoint_collect_status): Declare.
	(fast_tracepoint_collecting): Declare.
	(force_unlock_trace_buffer): Declare.
	(handle_tracepoint_bkpts): Declare.
	(initialize_low_tracepoint)
	(supply_fast_tracepoint_registers) [IN_PROCESS_AGENT]: Declare.
	* target.h (struct target_ops) <stabilize_threads,
	install_fast_tracepoint_jump_pad>: New fields.
	(stabilize_threads, install_fast_tracepoint_jump_pad): New.
	* tracepoint.c [HAVE_MALLOC_H]: Include malloc.h.
	[HAVE_STDINT_H]: Include stdint.h.
	(trace_debug_1): Rename to ...
	(trace_vdebug): ... this.
	(trace_debug): Rename to ...
	(trace_debug_1): ... this.  Add `level' parameter.
	(trace_debug): New.
	(ATTR_USED, ATTR_NOINLINE): New.
	(IP_AGENT_EXPORT): New.
	(gdb_tp_heap_buffer, gdb_jump_pad_buffer, gdb_jump_pad_buffer_end)
	(collecting, gdb_collect, stop_tracing, flush_trace_buffer)
	(about_to_request_buffer_space, trace_buffer_is_full)
	(stopping_tracepoint, expr_eval_result, error_tracepoint)
	(tracepoints, tracing, trace_buffer_ctrl, trace_buffer_ctrl_curr)
	(trace_buffer_lo, trace_buffer_hi, traceframe_read_count)
	(traceframe_write_count, traceframes_created)
	(trace_state_variables)
	New renaming defines.
	(struct ipa_sym_addresses): New.
	(STRINGIZE_1, STRINGIZE, IPA_SYM): New.
	(symbol_list): New.
	(ipa_sym_addrs): New.
	(all_tracepoint_symbols_looked_up): New.
	(in_process_agent_loaded): New.
	(write_e_ipa_not_loaded): New.
	(maybe_write_ipa_not_loaded): New.
	(tracepoint_look_up_symbols): New.
	(debug_threads) [IN_PROCESS_AGENT]: New.
	(read_inferior_memory) [IN_PROCESS_AGENT]: New.
	(UNKNOWN_SIDE_EFFECTS): New.
	(stop_tracing): New.
	(flush_trace_buffer): New.
	(stop_tracing_bkpt): New.
	(flush_trace_buffer_bkpt): New.
	(read_inferior_integer): New.
	(read_inferior_uinteger): New.
	(read_inferior_data_pointer): New.
	(write_inferior_data_pointer): New.
	(write_inferior_integer): New.
	(write_inferior_uinteger): New.
	(struct collect_static_trace_data_action): Delete.
	(enum tracepoint_type): New.
	(struct tracepoint) <type>: New field `type'.
	<actions_str, step_actions, step_actions_str>: Only include in GDBserver.
	<orig_size, obj_addr_on_target, adjusted_insn_addr>
	<adjusted_insn_addr_end, jump_pad, jump_pad_end>: New fields.
	(tracepoints): Use IP_AGENT_EXPORT.
	(last_tracepoint): Don't include in the IPA.
	(stopping_tracepoint): Use IP_AGENT_EXPORT.
	(trace_buffer_is_full): Use IP_AGENT_EXPORT.
	(alloced_trace_state_variables): New.
	(trace_state_variables): Use IP_AGENT_EXPORT.
	(traceframe_t): Delete unused variable.
	(circular_trace_buffer): Don't include in the IPA.
	(trace_buffer_start): Delete.
	(struct trace_buffer_control): New.
	(trace_buffer_free): Delete.
	(struct ipa_trace_buffer_control): New.
	(GDBSERVER_FLUSH_COUNT_MASK, GDBSERVER_FLUSH_COUNT_MASK_PREV)
	(GDBSERVER_FLUSH_COUNT_MASK_CURR, GDBSERVER_UPDATED_FLUSH_COUNT_BIT):
	New.
	(trace_buffer_ctrl): New.
	(TRACE_BUFFER_CTRL_CURR): New.
	(trace_buffer_start, trace_buffer_free, trace_buffer_end_free):
	Reimplement as macros.
	(trace_buffer_wrap): Delete.
	(traceframe_write_count, traceframe_read_count)
	(traceframes_created, tracing): Use IP_AGENT_EXPORT.
	(struct tracepoint_hit_ctx) <type>: New field.
	(struct fast_tracepoint_ctx): New.
	(memory_barrier): New.
	(cmpxchg): New.
	(record_tracepoint_error): Update atomically in the IPA.
	(clear_inferior_trace_buffer): New.
	(about_to_request_buffer_space): New.
	(trace_buffer_alloc): Handle GDBserver and inferior simulatenous
	updating the same buffer.
	(add_tracepoint): Default the tracepoint's type to trap
	tracepoint, and orig_size to -1.
	(get_trace_state_variable) [IN_PROCESS_AGENT]: Handle allocated
	internal variables.
	(create_trace_state_variable): New parameter `gdb'.  Handle it.
	(clear_installed_tracepoints): Clear fast tracepoint jumps.
	(cmd_qtdp): Handle fast tracepoints.
	(cmd_qtdv): Adjust.
	(max_jump_pad_size): New.
	(gdb_jump_pad_head): New.
	(get_jump_space_head): New.
	(claim_jump_space): New.
	(sort_tracepoints): New.
	(MAX_JUMP_SIZE): New.
	(cmd_qtstart): Handle fast tracepoints.  Sync tracepoints with the
	IPA.
	(stop_tracing) [IN_PROCESS_AGENT]: Don't include the tdisconnected
	support.  Upload fast traceframes, and delete internal IPA
	breakpoints.
	(stop_tracing_handler): New.
	(flush_trace_buffer_handler): New.
	(cmd_qtstop): Upload fast tracepoints.
	(response_tracepoint): Handle fast tracepoints.
	(tracepoint_finished_step): Upload fast traceframes.  Set the
	tracepoint hit context's tracepoint type.
	(handle_tracepoint_bkpts): New.
	(tracepoint_was_hit): Set the tracepoint hit context's tracepoint
	type.  Add comment about fast tracepoints.
	(collect_data_at_tracepoint) [IN_PROCESS_AGENT]: Don't access the
	non-existing action_str field.
	(get_context_regcache): Handle fast tracepoints.
	(do_action_at_tracepoint) [!IN_PROCESS_AGENT]: Don't write the PC
	to the regcache.
	(fast_tracepoint_from_jump_pad_address): New.
	(fast_tracepoint_from_ipa_tpoint_address): New.
	(collecting_t): New.
	(force_unlock_trace_buffer): New.
	(fast_tracepoint_collecting): New.
	(collecting): New.
	(gdb_collect): New.
	(write_inferior_data_ptr): New.
	(target_tp_heap): New.
	(target_malloc): New.
	(download_agent_expr): New.
	(UALIGN): New.
	(download_tracepoints): New.
	(download_trace_state_variables): New.
	(upload_fast_traceframes): New.
	(IPA_FIRST_TRACEFRAME): New.
	(IPA_NEXT_TRACEFRAME_1): New.
	(IPA_NEXT_TRACEFRAME): New.
	[IN_PROCESS_AGENT]: Include sys/mman.h and fcntl.h.
	[IN_PROCESS_AGENT] (gdb_tp_heap_buffer, gdb_jump_pad_buffer)
	(gdb_jump_pad_buffer_end): New.
	[IN_PROCESS_AGENT] (initialize_tracepoint_ftlib): New.
	(initialize_tracepoint): Adjust.
	[IN_PROCESS_AGENT]: Allocate the IPA heap, and jump pad scratch
	buffer.  Initialize the low module.
	* utils.c (PREFIX, TOOLNAME): New.
	(malloc_failure): Use PREFIX.
	(error): In the IPA, an error causes an exit.
	(fatal, warning): Use PREFIX.
	(internal_error): Use TOOLNAME.
	(NUMCELLS): Increase to 10.
	* configure, config.in: Regenerate.

gdb/
2010-06-01  Pedro Alves  <pedro@codesourcery.com>

	* NEWS: Mention gdbserver fast tracepoints support.

gdb/doc/
2010-06-01  Pedro Alves  <pedro@codesourcery.com>

	* gdb.texinfo (Set Tracepoints): Mention tracepoints support in
	gdbserver, and add cross reference.
	(Tracepoints support in gdbserver): New subsection.

gdb/gdbserver/remote-utils.c

@@ -1127,7 +1127,7 @@ write_enn (char *buf)
 }
 
 void
-convert_int_to_ascii (unsigned char *from, char *to, int n)
+convert_int_to_ascii (const unsigned char *from, char *to, int n)
 {
   int nib;
   int ch;
@@ -1144,7 +1144,7 @@ convert_int_to_ascii (unsigned char *from, char *to, int n)
 
 
 void
-convert_ascii_to_int (char *from, unsigned char *to, int n)
+convert_ascii_to_int (const char *from, unsigned char *to, int n)
 {
   int nib1, nib2;
   while (n--)
@@ -1354,7 +1354,7 @@ decode_m_packet (char *from, CORE_ADDR *mem_addr_ptr, unsigned int *len_ptr)
 
 void
 decode_M_packet (char *from, CORE_ADDR *mem_addr_ptr, unsigned int *len_ptr,
-		 unsigned char *to)
+		 unsigned char **to_p)
 {
   int i = 0;
   char ch;
@@ -1372,12 +1372,15 @@ decode_M_packet (char *from, CORE_ADDR *mem_addr_ptr, unsigned int *len_ptr,
       *len_ptr |= fromhex (ch) & 0x0f;
     }
 
-  convert_ascii_to_int (&from[i++], to, *len_ptr);
+  if (*to_p == NULL)
+    *to_p = xmalloc (*len_ptr);
+
+  convert_ascii_to_int (&from[i++], *to_p, *len_ptr);
 }
 
 int
 decode_X_packet (char *from, int packet_len, CORE_ADDR *mem_addr_ptr,
-		 unsigned int *len_ptr, unsigned char *to)
+		 unsigned int *len_ptr, unsigned char **to_p)
 {
   int i = 0;
   char ch;
@@ -1395,8 +1398,11 @@ decode_X_packet (char *from, int packet_len, CORE_ADDR *mem_addr_ptr,
       *len_ptr |= fromhex (ch) & 0x0f;
     }
 
+  if (*to_p == NULL)
+    *to_p = xmalloc (*len_ptr);
+
   if (remote_unescape_input ((const gdb_byte *) &from[i], packet_len - i,
-			     to, *len_ptr) != *len_ptr)
+			     *to_p, *len_ptr) != *len_ptr)
     return -1;
 
   return 0;
@@ -1565,6 +1571,101 @@ look_up_one_symbol (const char *name, CORE_ADDR *addrp, int may_ask_gdb)
   return 1;
 }
 
+/* Relocate an instruction to execute at a different address.  OLDLOC
+   is the address in the inferior memory where the instruction to
+   relocate is currently at.  On input, TO points to the destination
+   where we want the instruction to be copied (and possibly adjusted)
+   to.  On output, it points to one past the end of the resulting
+   instruction(s).  The effect of executing the instruction at TO
+   shall be the same as if executing it at FROM.  For example, call
+   instructions that implicitly push the return address on the stack
+   should be adjusted to return to the instruction after OLDLOC;
+   relative branches, and other PC-relative instructions need the
+   offset adjusted; etc.  Returns 0 on success, -1 on failure.  */
+
+int
+relocate_instruction (CORE_ADDR *to, CORE_ADDR oldloc)
+{
+  char own_buf[266];
+  int len;
+  ULONGEST written = 0;
+
+  /* Send the request.  */
+  strcpy (own_buf, "qRelocInsn:");
+  sprintf (own_buf, "qRelocInsn:%s;%s", paddress (oldloc),
+	   paddress (*to));
+  if (putpkt (own_buf) < 0)
+    return -1;
+
+  /* FIXME:  Eventually add buffer overflow checking (to getpkt?)  */
+  len = getpkt (own_buf);
+  if (len < 0)
+    return -1;
+
+  /* We ought to handle pretty much any packet at this point while we
+     wait for the qRelocInsn "response".  That requires re-entering
+     the main loop.  For now, this is an adequate approximation; allow
+     GDB to access memory.  */
+  while (own_buf[0] == 'm' || own_buf[0] == 'M' || own_buf[0] == 'X')
+    {
+      CORE_ADDR mem_addr;
+      unsigned char *mem_buf = NULL;
+      unsigned int mem_len;
+
+      if (own_buf[0] == 'm')
+	{
+	  decode_m_packet (&own_buf[1], &mem_addr, &mem_len);
+	  mem_buf = xmalloc (mem_len);
+	  if (read_inferior_memory (mem_addr, mem_buf, mem_len) == 0)
+	    convert_int_to_ascii (mem_buf, own_buf, mem_len);
+	  else
+	    write_enn (own_buf);
+	}
+      else if (own_buf[0] == 'X')
+	{
+	  if (decode_X_packet (&own_buf[1], len - 1, &mem_addr,
+			       &mem_len, &mem_buf) < 0
+	      || write_inferior_memory (mem_addr, mem_buf, mem_len) != 0)
+	    write_enn (own_buf);
+	  else
+	    write_ok (own_buf);
+	}
+      else
+	{
+	  decode_M_packet (&own_buf[1], &mem_addr, &mem_len, &mem_buf);
+	  if (write_inferior_memory (mem_addr, mem_buf, mem_len) == 0)
+	    write_ok (own_buf);
+	  else
+	    write_enn (own_buf);
+	}
+      free (mem_buf);
+      if (putpkt (own_buf) < 0)
+	return -1;
+      len = getpkt (own_buf);
+      if (len < 0)
+	return -1;
+    }
+
+  if (own_buf[0] == 'E')
+    {
+      warning ("An error occurred while relocating an instruction: %s\n",
+	       own_buf);
+      return -1;
+    }
+
+  if (strncmp (own_buf, "qRelocInsn:", strlen ("qRelocInsn:")) != 0)
+    {
+      warning ("Malformed response to qRelocInsn, ignoring: %s\n",
+	       own_buf);
+      return -1;
+    }
+
+  unpack_varlen_hex (own_buf + strlen ("qRelocInsn:"), &written);
+
+  *to += written;
+  return 0;
+}
+
 void
 monitor_output (const char *msg)
 {