[PATCH 2/5 v4] powerpc: Support z-point type in gdbserver.

[Marcin Kościelnicki]

Another old approved patch that I'd like to push.  Testing on 
ppc+ppc64+ppc64le:

gdb.base/dprintf.exp: agent: 1st dprintf UNSUPPORTED -> PASS×3
gdb.base/jit.exp: PIE: one_jit_test-1: set var libname = 
"SHLIBDIR/jit-solib.so" PASS -> FAIL, on ppc64 only (I don't consider 
that one a problem, since jit.exp already has lots of similiar FAILs for 
this arch, nothing really new is broken here)
gdb.mi/mi-dprintf.exp: mi expect stop FAIL×5 -> PASS×4
gdb.threads/forking-threads-plus-breakpoint.exp: cond_bp_target=1: 
detach_on_fork=on: displaced=off FAIL -> PASS×3
gdb.threads/process-dies-while-handling-bp.exp: non_stop=on: 
cond_bp_target=1: KFAIL (memory error) -> KFAIL (prompt)
gdb.threads/process-dies-while-handling-bp.exp: non_stop=off: 
cond_bp_target=[01]: inferior 1 exited PASS×2 -> KFAIL (PRMS: gdb/18749)

Fixes a lot of gdb.trace tests if I enable tracepoints.

On 27/06/15 18:21, Wei-cheng Wang wrote:
> Support z-point, so tracepoints and breakpoints can be inserted at the same
> location.
>
> gdb/gdbserver/ChangeLog
>
> 2015-06-27  Wei-cheng Wang  <cole945@gmail.com>
>
> 	* linux-ppc-low.c (ppc_supports_z_point_type): New function:
> 	(ppc_insert_point, ppc_remove_point): Insert/remove z-packet breakpoints.
> 	(ppc64_emit_ops_vector): Add target ops - ppc_supports_z_point_type,
> 	ppc_insert_point, ppc_remove_point.
> ---
>   gdb/gdbserver/linux-ppc-low.c | 69 +++++++++++++++++++++++++++++++++++++++++--
>   1 file changed, 66 insertions(+), 3 deletions(-)
>
> diff --git a/gdb/gdbserver/linux-ppc-low.c b/gdb/gdbserver/linux-ppc-low.c
> index 188fac0..41ec281 100644
> --- a/gdb/gdbserver/linux-ppc-low.c
> +++ b/gdb/gdbserver/linux-ppc-low.c
> @@ -512,6 +512,69 @@ ppc_breakpoint_at (CORE_ADDR where)
>     return 0;
>   }
>
> +/* Implement supports_z_point_type target-ops.
> +   Returns true if type Z_TYPE breakpoint is supported.
> +
> +   Handling software breakpoint at server side, so tracepoints
> +   and breakpoints can be inserted at the same location.  */
> +
> +static int
> +ppc_supports_z_point_type (char z_type)
> +{
> +  switch (z_type)
> +    {
> +    case Z_PACKET_SW_BP:
> +      return 1;
> +    case Z_PACKET_HW_BP:
> +    case Z_PACKET_WRITE_WP:
> +    case Z_PACKET_ACCESS_WP:
> +    default:
> +      return 0;
> +    }
> +}
> +
> +/* Implement insert_point target-ops.
> +   Returns 0 on success, -1 on failure and 1 on unsupported.  */
> +
> +static int
> +ppc_insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
> +		  int size, struct raw_breakpoint *bp)
> +{
> +  switch (type)
> +    {
> +    case raw_bkpt_type_sw:
> +      return insert_memory_breakpoint (bp);
> +
> +    case raw_bkpt_type_hw:
> +    case raw_bkpt_type_write_wp:
> +    case raw_bkpt_type_access_wp:
> +    default:
> +      /* Unsupported.  */
> +      return 1;
> +    }
> +}
> +
> +/* Implement remove_point target-ops.
> +   Returns 0 on success, -1 on failure and 1 on unsupported.  */
> +
> +static int
> +ppc_remove_point (enum raw_bkpt_type type, CORE_ADDR addr,
> +		  int size, struct raw_breakpoint *bp)
> +{
> +  switch (type)
> +    {
> +    case raw_bkpt_type_sw:
> +      return remove_memory_breakpoint (bp);
> +
> +    case raw_bkpt_type_hw:
> +    case raw_bkpt_type_write_wp:
> +    case raw_bkpt_type_access_wp:
> +    default:
> +      /* Unsupported.  */
> +      return 1;
> +    }
> +}
> +
>   /* Provide only a fill function for the general register set.  ps_lgetregs
>      will use this for NPTL support.  */
>
> @@ -690,9 +753,9 @@ struct linux_target_ops the_low_target = {
>     NULL,
>     0,
>     ppc_breakpoint_at,
> -  NULL, /* supports_z_point_type */
> -  NULL,
> -  NULL,
> +  ppc_supports_z_point_type,
> +  ppc_insert_point,
> +  ppc_remove_point,
>     NULL,
>     NULL,
>     ppc_collect_ptrace_register,
>