[3/3,v2] Fast tracepoint for powerpc64le
Commit Message
Hi,
This changes are used to build unavailable frame id for tracepoint.
It is related to this
https://sourceware.org/ml/gdb-patches/2013-12/msg00535.html
Thanks,
Wei-cheng
--
gdb/ChangeLog
2015-02-25 Wei-cheng Wang <cole945@gmail.com>
* rs6000-tdep.c (rs6000_frame_cache, rs6000_frame_this_id): Handle
unavailable PC/SP to build unavailable frame.
---
gdb/rs6000-tdep.c | 49 ++++++++++++++++++++++++++++++++++++-------------
1 file changed, 36 insertions(+), 13 deletions(-)
Comments
On 02/25/2015 03:27 PM, Wei-cheng Wang wrote:
> @@ -3341,6 +3357,13 @@ rs6000_frame_this_id (struct frame_info *this_frame, void **this_cache,
> {
> struct rs6000_frame_cache *info = rs6000_frame_cache (this_frame,
> this_cache);
> +
> + if (!info->base_p)
> + {
> + (*this_id) = frame_id_build_unavailable_stack (0);
It's best if this fills in the PC too, when possible.
The normal path below this uses get_frame_func (this_frame).
Can we use that here? If that can throw unavailable,
perhaps we could have rs6000_frame_cache save it in the
frame cache object, inside the TRY_CATCH.
Thanks,
Pedro Alves
@@ -3152,11 +3152,17 @@ struct rs6000_frame_cache
CORE_ADDR base;
CORE_ADDR initial_sp;
struct trad_frame_saved_reg *saved_regs;
+
+ /* Set BASE_P to true if this frame cache is properly initialized.
+ Otherwise set to false because some registers or memory cannot
+ collected. */
+ int base_p;
};
static struct rs6000_frame_cache *
rs6000_frame_cache (struct frame_info *this_frame, void **this_cache)
{
+ volatile struct gdb_exception ex;
struct rs6000_frame_cache *cache;
struct gdbarch *gdbarch = get_frame_arch (this_frame);
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
@@ -3171,19 +3177,28 @@ rs6000_frame_cache (struct frame_info *this_frame, void **this_cache)
(*this_cache) = cache;
cache->saved_regs = trad_frame_alloc_saved_regs (this_frame);
- func = get_frame_func (this_frame);
- pc = get_frame_pc (this_frame);
- skip_prologue (gdbarch, func, pc, &fdata);
-
- /* Figure out the parent's stack pointer. */
-
- /* NOTE: cagney/2002-04-14: The ->frame points to the inner-most
- address of the current frame. Things might be easier if the
- ->frame pointed to the outer-most address of the frame. In
- the mean time, the address of the prev frame is used as the
- base address of this frame. */
- cache->base = get_frame_register_unsigned
- (this_frame, gdbarch_sp_regnum (gdbarch));
+ TRY_CATCH (ex, RETURN_MASK_ERROR)
+ {
+ func = get_frame_func (this_frame);
+ pc = get_frame_pc (this_frame);
+ skip_prologue (gdbarch, func, pc, &fdata);
+
+ /* Figure out the parent's stack pointer. */
+
+ /* NOTE: cagney/2002-04-14: The ->frame points to the inner-most
+ address of the current frame. Things might be easier if the
+ ->frame pointed to the outer-most address of the frame. In
+ the mean time, the address of the prev frame is used as the
+ base address of this frame. */
+ cache->base = get_frame_register_unsigned
+ (this_frame, gdbarch_sp_regnum (gdbarch));
+ }
+ if (ex.reason < 0)
+ {
+ if (ex.error != NOT_AVAILABLE_ERROR)
+ throw_exception (ex);
+ return (*this_cache);
+ }
/* If the function appears to be frameless, check a couple of likely
indicators that we have simply failed to find the frame setup.
@@ -3332,6 +3347,7 @@ rs6000_frame_cache (struct frame_info *this_frame, void **this_cache)
cache->initial_sp
= get_frame_register_unsigned (this_frame, fdata.alloca_reg);
+ cache->base_p = 1;
return cache;
}
@@ -3341,6 +3357,13 @@ rs6000_frame_this_id (struct frame_info *this_frame, void **this_cache,
{
struct rs6000_frame_cache *info = rs6000_frame_cache (this_frame,
this_cache);
+
+ if (!info->base_p)
+ {
+ (*this_id) = frame_id_build_unavailable_stack (0);
+ return;
+ }
+
/* This marks the outermost frame. */
if (info->base == 0)
return;