Commit: Export AArch64 sum's single step function

Nick Clifton
2016-08-11T14:04:18Z

Hi Guys,

I am checking in the patch below to export the AArch64 sim's single
step function, so that it can be used when a tool needs to just
execute one instruction at a time. The patch also fixes a minor bug
in sim_create_inferior which would seg-fault if called without an
initialised bfd object.

Cheers
Nick

sim/ChangeLog
2016-08-11 Nick Clifton <nickc@redhat.com>

* interp.c (sim_create_inferior): Allow for being called with a
NULL abfd parameter. If a bfd is provided, initialise the sim
with that start address.
* simulator.c (HALT_NYI): Just print out the numeric value of the
instruction when not tracing.
(aarch64_step): Change from static to global.
* simulator.h: Add a prototype for aarch64_step().

diff --git a/sim/aarch64/interp.c b/sim/aarch64/interp.c
index 8ae78c4..2a3ff26 100644
--- a/sim/aarch64/interp.c
+++ b/sim/aarch64/interp.c
@@ -135,7 +135,7 @@ sim_create_inferior (SIM_DESC sd, struct bfd *abfd,
char * const *argv, char * const *env)
{
sim_cpu *cpu = STATE_CPU (sd, 0);
- long storage;
+ long storage = 0;
bfd_vma addr = 0;

if (abfd != NULL)
@@ -154,7 +154,8 @@ sim_create_inferior (SIM_DESC sd, struct bfd *abfd,
STATE_PROG_ARGV (sd) = dupargv (argv);
}

- storage = bfd_get_symtab_upper_bound (abfd);
+ if (abfd != NULL)
+ storage = bfd_get_symtab_upper_bound (abfd);
if (storage > 0)
{
symtab = (asymbol **) xmalloc (storage);
@@ -163,7 +164,7 @@ sim_create_inferior (SIM_DESC sd, struct bfd *abfd,
qsort (symtab, symcount, sizeof (asymbol *), compare_symbols);
}

- aarch64_init (cpu, bfd_get_start_address (abfd));
+ aarch64_init (cpu, addr);

return SIM_RC_OK;
}
@@ -332,7 +333,6 @@ sim_open (SIM_OPEN_KIND kind,
struct bfd * abfd,
char * const * argv)
{
- int i;
sim_cpu *cpu;
SIM_DESC sd = sim_state_alloc (kind, callback);

diff --git a/sim/aarch64/simulator.c b/sim/aarch64/simulator.c
index 45844e2..150bf34 100644
--- a/sim/aarch64/simulator.c
+++ b/sim/aarch64/simulator.c
@@ -64,10 +64,8 @@
" exe addr %" PRIx64, \
__LINE__, aarch64_get_PC (cpu)); \
if (! TRACE_ANY_P (cpu)) \
- { \
- sim_io_eprintf (CPU_STATE (cpu), "SIM Error: Unimplemented instruction: "); \
- trace_disasm (CPU_STATE (cpu), cpu, aarch64_get_PC (cpu)); \
- } \
+ sim_io_eprintf (CPU_STATE (cpu), "SIM Error: Unimplemented instruction: %#08x\n", \
+ aarch64_get_instr (cpu)); \
sim_engine_halt (CPU_STATE (cpu), cpu, NULL, aarch64_get_PC (cpu),\
sim_stopped, SIM_SIGABRT); \
} \
@@ -14074,7 +14072,7 @@ aarch64_decode_and_execute (sim_cpu *cpu, uint64_t pc)
}
}

-static bfd_boolean
+bfd_boolean
aarch64_step (sim_cpu *cpu)
{
uint64_t pc = aarch64_get_PC (cpu);
diff --git a/sim/aarch64/simulator.h b/sim/aarch64/simulator.h
index 08bed3d..a17bd21 100644
--- a/sim/aarch64/simulator.h
+++ b/sim/aarch64/simulator.h
@@ -47,6 +47,10 @@ extern void aarch64_init (sim_cpu *, uint64_t);

extern void aarch64_run (SIM_DESC);

+/* Call this to execute one instruction at the current PC. */
+
+extern bfd_boolean aarch64_step (sim_cpu *);
+
extern const char * aarch64_get_func (uint64_t);
extern uint64_t aarch64_get_sym_value (const char *);
extern void aarch64_init_LIT_table (void);