[PATCH 9/9] Throw exception in aarch64 unwinder

[Yao Qi <qiyaoltc at gmail dot com>]

gdb:

2017-07-31  Yao Qi  <yao.qi@linaro.org>

	* aarch64-tdep.c (aarch64_prologue_cache) <available_p>: Remove.
	(aarch64_make_prologue_cache_1): Update.
	(aarch64_make_prologue_cache): Don't catch exception.
	(aarch64_prologue_frame_unwind_stop_reason): Don't check
	cache->available_p.
	(aarch64_prologue_this_id): Likewise.
	(aarch64_make_stub_cache): Don't catch exceptions.
	(aarch64_stub_frame_unwind_stop_reason): Don't check
	cache->available_p.
	(aarch64_stub_this_id): Likewise.
---
 gdb/aarch64-tdep.c | 48 ++++++------------------------------------------
 1 file changed, 6 insertions(+), 42 deletions(-)

diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c
index 75bb00f..19533af 100644
--- a/gdb/aarch64-tdep.c
+++ b/gdb/aarch64-tdep.c
@@ -174,9 +174,6 @@ struct aarch64_prologue_cache
      to identify this frame.  */
   CORE_ADDR prev_sp;
 
-  /* Is the target available to read from?  */
-  int available_p;
-
   /* The frame base for this frame is just prev_sp - frame size.
      FRAMESIZE is the distance from the frame pointer to the
      initial stack pointer.  */
@@ -744,8 +741,6 @@ aarch64_make_prologue_cache_1 (struct frame_info *this_frame,
       cache->saved_regs[reg].addr += cache->prev_sp;
 
   cache->func = get_frame_func (this_frame);
-
-  cache->available_p = 1;
 }
 
 /* Allocate and fill in *THIS_CACHE with information about the prologue of
@@ -765,16 +760,7 @@ aarch64_make_prologue_cache (struct frame_info *this_frame, void **this_cache)
   cache->saved_regs = trad_frame_alloc_saved_regs (this_frame);
   *this_cache = cache;
 
-  TRY
-    {
-      aarch64_make_prologue_cache_1 (this_frame, cache);
-    }
-  CATCH (ex, RETURN_MASK_ERROR)
-    {
-      if (ex.error != NOT_AVAILABLE_ERROR)
-	throw_exception (ex);
-    }
-  END_CATCH
+  aarch64_make_prologue_cache_1 (this_frame, cache);
 
   return cache;
 }
@@ -788,9 +774,6 @@ aarch64_prologue_frame_unwind_stop_reason (struct frame_info *this_frame,
   struct aarch64_prologue_cache *cache
     = aarch64_make_prologue_cache (this_frame, this_cache);
 
-  if (!cache->available_p)
-    return UNWIND_UNAVAILABLE;
-
   /* Halt the backtrace at "_start".  */
   if (cache->prev_pc <= gdbarch_tdep (get_frame_arch (this_frame))->lowest_pc)
     return UNWIND_OUTERMOST;
@@ -812,10 +795,7 @@ aarch64_prologue_this_id (struct frame_info *this_frame,
   struct aarch64_prologue_cache *cache
     = aarch64_make_prologue_cache (this_frame, this_cache);
 
-  if (!cache->available_p)
-    *this_id = frame_id_build_unavailable_stack (cache->func);
-  else
-    *this_id = frame_id_build (cache->prev_sp, cache->func);
+  *this_id = frame_id_build (cache->prev_sp, cache->func);
 }
 
 /* Implement the "prev_register" frame_unwind method.  */
@@ -889,19 +869,9 @@ aarch64_make_stub_cache (struct frame_info *this_frame, void **this_cache)
   cache->saved_regs = trad_frame_alloc_saved_regs (this_frame);
   *this_cache = cache;
 
-  TRY
-    {
-      cache->prev_sp = get_frame_register_unsigned (this_frame,
-						    AARCH64_SP_REGNUM);
-      cache->prev_pc = get_frame_pc (this_frame);
-      cache->available_p = 1;
-    }
-  CATCH (ex, RETURN_MASK_ERROR)
-    {
-      if (ex.error != NOT_AVAILABLE_ERROR)
-	throw_exception (ex);
-    }
-  END_CATCH
+  cache->prev_sp = get_frame_register_unsigned (this_frame,
+						AARCH64_SP_REGNUM);
+  cache->prev_pc = get_frame_pc (this_frame);
 
   return cache;
 }
@@ -915,9 +885,6 @@ aarch64_stub_frame_unwind_stop_reason (struct frame_info *this_frame,
   struct aarch64_prologue_cache *cache
     = aarch64_make_stub_cache (this_frame, this_cache);
 
-  if (!cache->available_p)
-    return UNWIND_UNAVAILABLE;
-
   return UNWIND_NO_REASON;
 }
 
@@ -930,10 +897,7 @@ aarch64_stub_this_id (struct frame_info *this_frame,
   struct aarch64_prologue_cache *cache
     = aarch64_make_stub_cache (this_frame, this_cache);
 
-  if (cache->available_p)
-    *this_id = frame_id_build (cache->prev_sp, cache->prev_pc);
-  else
-    *this_id = frame_id_build_unavailable_stack (cache->prev_pc);
+  *this_id = frame_id_build (cache->prev_sp, cache->prev_pc);
 }
 
 /* Implement the "sniffer" frame_unwind method.  */
-- 
1.9.1