binutils-gdb/gdb/tic6x-tdep.h
Simon Marchi 8480a37e14 gdb: pass frames as const frame_info_ptr &
We currently pass frames to function by value, as `frame_info_ptr`.
This is somewhat expensive:

 - the size of `frame_info_ptr` is 64 bytes, which is a bit big to pass
   by value
 - the constructors and destructor link/unlink the object in the global
   `frame_info_ptr::frame_list` list.  This is an `intrusive_list`, so
   it's not so bad: it's just assigning a few points, there's no memory
   allocation as if it was `std::list`, but still it's useless to do
   that over and over.

As suggested by Tom Tromey, change many function signatures to accept
`const frame_info_ptr &` instead of `frame_info_ptr`.

Some functions reassign their `frame_info_ptr` parameter, like:

  void
  the_func (frame_info_ptr frame)
  {
    for (; frame != nullptr; frame = get_prev_frame (frame))
      {
        ...
      }
  }

I wondered what to do about them, do I leave them as-is or change them
(and need to introduce a separate local variable that can be
re-assigned).  I opted for the later for consistency.  It might not be
clear why some functions take `const frame_info_ptr &` while others take
`frame_info_ptr`.  Also, if a function took a `frame_info_ptr` because
it did re-assign its parameter, I doubt that we would think to change it
to `const frame_info_ptr &` should the implementation change such that
it doesn't need to take `frame_info_ptr` anymore.  It seems better to
have a simple rule and apply it everywhere.

Change-Id: I59d10addef687d157f82ccf4d54f5dde9a963fd0
Approved-By: Andrew Burgess <aburgess@redhat.com>
2024-02-20 10:42:25 -05:00

61 lines
1.9 KiB
C

/* GNU/Linux on TI C6x target support.
Copyright (C) 2011-2024 Free Software Foundation, Inc.
Contributed by Yao Qi <yao@codesourcery.com>
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/>. */
#ifndef TIC6X_TDEP_H
#define TIC6X_TDEP_H
#include "gdbarch.h"
enum
{
TIC6X_A4_REGNUM = 4,
TIC6X_A5_REGNUM = 5,
TIC6X_FP_REGNUM = 15, /* Frame Pointer: A15 */
TIC6X_B0_REGNUM = 16,
TIC6X_RA_REGNUM = 19, /* Return address: B3 */
TIC6X_B4_REGNUM = 20,
TIC6X_B5_REGNUM = 21,
TIC6X_DP_REGNUM = 30, /* Data Page Pointer: B14 */
TIC6X_SP_REGNUM = 31, /* Stack Pointer: B15 */
TIC6X_CSR_REGNUM = 32,
TIC6X_PC_REGNUM = 33,
TIC6X_NUM_CORE_REGS = 33, /* The number of core registers */
TIC6X_RILC_REGNUM = 68,
TIC6X_NUM_REGS /* The number of registers */
};
#define TIC6X_INST_SWE 0x10000000
extern const gdb_byte tic6x_bkpt_illegal_opcode_be[];
extern const gdb_byte tic6x_bkpt_illegal_opcode_le[];
/* Target-dependent structure in gdbarch. */
struct tic6x_gdbarch_tdep : gdbarch_tdep_base
{
/* Return the expected next PC if FRAME is stopped at a syscall
instruction. */
CORE_ADDR (*syscall_next_pc) (const frame_info_ptr &frame) = nullptr;
const gdb_byte *breakpoint = nullptr; /* Breakpoint instruction. */
int has_gp = 0; /* Has general purpose registers A16 - A31 and B16 - B31. */
};
#endif /* TIC6X_TDEP_H */