binutils-gdb/sim/frv/sim-if.c
Mike Frysinger ba307cddcf sim: overhaul alignment settings management
Currently, the sim-config module will abort if alignment settings
haven't been specified by the port's configure.ac.  This is a bit
weird when we've allowed SIM_AC_OPTION_ALIGNMENT to seem like it's
optional to use.  Thus everyone invokes it.

There are 4 alignment settings, but really only 2 matters: strict
and nonstrict.  The "mixed" setting is just the default ("unset"),
and "forced" isn't used directly by anyone (it's available as a
runtime option for some ports).

The m4 macro has 2 args: the "wire" settings (which represents the
hardwired port behavior), and the default settings (which are used
if nothing else is specified).  If none are specified, then the
build won't work (see above as if SIM_AC_OPTION_ALIGNMENT wasn't
called).  If default settings are provided, then that is used, but
we allow the user to override at runtime.  Otherwise, the "wire"
settings are used and user runtime options to change are ignored.

Most ports specify a default, or set the "wire" to nonstrict.  A
few set "wire" to strict, but it's not clear that's necessary as
it doesn't make the code behavior, by default, any different.  It
might make things a little faster, but we should provide the user
the choice of the compromises to make: force a specific mode at
compile time for faster runtime, or allow the choice at runtime.
More likely it seems like an oversight when these ports were
initially created, and/or copied & pasted from existing ports.

With all that backstory, let's get to what this commit does.

First kill off the idea of a compile-time default alignment and
set it to nonstrict in the common code.  For any ports that want
strict alignment by default, that code is moved to sim_open while
initializing the sim.  That means WITH_DEFAULT_ALIGNMENT can be
completely removed.

Moving the default alignment to the runtime also allows removal
of setting the "wire" settings at configure time.  Which allows
removing of all arguments to SIM_AC_OPTION_ALIGNMENT and moving
that call to common code.

The macro logic can be reworked to not pass WITH_ALIGNMENT as -D
CPPFLAG and instead move it to config.h.

All of these taken together mean we can hoist the macro up to the
top level and share it among all sims so behavior is consistent
among all the ports.
2021-06-12 21:14:50 -04:00

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/* Main simulator entry points specific to the FRV.
Copyright (C) 1998-2021 Free Software Foundation, Inc.
Contributed by Red Hat.
This file is part of the GNU simulators.
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/>. */
/* This must come before any other includes. */
#include "defs.h"
#define WANT_CPU
#define WANT_CPU_FRVBF
#include "sim-main.h"
#include <stdlib.h>
#include "sim-options.h"
#include "libiberty.h"
#include "bfd.h"
#include "elf-bfd.h"
static void free_state (SIM_DESC);
static void print_frv_misc_cpu (SIM_CPU *cpu, int verbose);
/* Cover function of sim_state_free to free the cpu buffers as well. */
static void
free_state (SIM_DESC sd)
{
if (STATE_MODULES (sd) != NULL)
sim_module_uninstall (sd);
sim_cpu_free_all (sd);
sim_state_free (sd);
}
/* Create an instance of the simulator. */
SIM_DESC
sim_open (SIM_OPEN_KIND kind, host_callback *callback, bfd *abfd,
char * const *argv)
{
char c;
int i;
unsigned long elf_flags = 0;
SIM_DESC sd = sim_state_alloc (kind, callback);
/* Set default options before parsing user options. */
current_alignment = STRICT_ALIGNMENT;
/* The cpu data is kept in a separately allocated chunk of memory. */
if (sim_cpu_alloc_all (sd, 1) != SIM_RC_OK)
{
free_state (sd);
return 0;
}
if (sim_pre_argv_init (sd, argv[0]) != SIM_RC_OK)
{
free_state (sd);
return 0;
}
/* These options override any module options.
Obviously ambiguity should be avoided, however the caller may wish to
augment the meaning of an option. */
sim_add_option_table (sd, NULL, frv_options);
/* The parser will print an error message for us, so we silently return. */
if (sim_parse_args (sd, argv) != SIM_RC_OK)
{
free_state (sd);
return 0;
}
/* Allocate core managed memory if none specified by user.
Use address 4 here in case the user wanted address 0 unmapped. */
if (sim_core_read_buffer (sd, NULL, read_map, &c, 4, 1) == 0)
sim_do_commandf (sd, "memory region 0,0x%lx", FRV_DEFAULT_MEM_SIZE);
/* check for/establish the reference program image */
if (sim_analyze_program (sd,
(STATE_PROG_ARGV (sd) != NULL
? *STATE_PROG_ARGV (sd)
: NULL),
abfd) != SIM_RC_OK)
{
free_state (sd);
return 0;
}
/* set machine and architecture correctly instead of defaulting to frv */
{
bfd *prog_bfd = STATE_PROG_BFD (sd);
if (prog_bfd != NULL)
{
struct elf_backend_data *backend_data;
if (bfd_get_arch (prog_bfd) != bfd_arch_frv)
{
sim_io_eprintf (sd, "%s: \"%s\" is not a FRV object file\n",
STATE_MY_NAME (sd),
bfd_get_filename (prog_bfd));
free_state (sd);
return 0;
}
backend_data = get_elf_backend_data (prog_bfd);
if (backend_data != NULL)
backend_data->elf_backend_object_p (prog_bfd);
elf_flags = elf_elfheader (prog_bfd)->e_flags;
}
}
/* Establish any remaining configuration options. */
if (sim_config (sd) != SIM_RC_OK)
{
free_state (sd);
return 0;
}
if (sim_post_argv_init (sd) != SIM_RC_OK)
{
free_state (sd);
return 0;
}
/* Open a copy of the cpu descriptor table. */
{
CGEN_CPU_DESC cd = frv_cgen_cpu_open_1 (STATE_ARCHITECTURE (sd)->printable_name,
CGEN_ENDIAN_BIG);
for (i = 0; i < MAX_NR_PROCESSORS; ++i)
{
SIM_CPU *cpu = STATE_CPU (sd, i);
CPU_CPU_DESC (cpu) = cd;
CPU_DISASSEMBLER (cpu) = sim_cgen_disassemble_insn;
CPU_ELF_FLAGS (cpu) = elf_flags;
}
frv_cgen_init_dis (cd);
}
/* CPU specific initialization. */
for (i = 0; i < MAX_NR_PROCESSORS; ++i)
{
SIM_CPU* cpu = STATE_CPU (sd, i);
frv_initialize (cpu, sd);
}
return sd;
}
void
frv_sim_close (SIM_DESC sd, int quitting)
{
int i;
/* Terminate cache support. */
for (i = 0; i < MAX_NR_PROCESSORS; ++i)
{
SIM_CPU* cpu = STATE_CPU (sd, i);
frv_cache_term (CPU_INSN_CACHE (cpu));
frv_cache_term (CPU_DATA_CACHE (cpu));
}
}
SIM_RC
sim_create_inferior (SIM_DESC sd, bfd *abfd, char * const *argv,
char * const *envp)
{
SIM_CPU *current_cpu = STATE_CPU (sd, 0);
SIM_ADDR addr;
if (abfd != NULL)
addr = bfd_get_start_address (abfd);
else
addr = 0;
sim_pc_set (current_cpu, addr);
/* Standalone mode (i.e. `run`) will take care of the argv for us in
sim_open() -> sim_parse_args(). But in debug mode (i.e. 'target sim'
with `gdb`), we need to handle it because the user can change the
argv on the fly via gdb's 'run'. */
if (STATE_PROG_ARGV (sd) != argv)
{
freeargv (STATE_PROG_ARGV (sd));
STATE_PROG_ARGV (sd) = dupargv (argv);
}
return SIM_RC_OK;
}