btrace: Use function segment index in insn iterator.

Remove FUNCTION pointer in struct btrace_insn_iterator and use an index into
the list of function segments instead.

4 files changed, 50 insertions, 29 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index d04197a..79e6fc4 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,21 @@
 2017-05-30  Tim Wiederhake  <tim.wiederhake@intel.com>
 
+	* btrace.c: (btrace_insn_get, btrace_insn_get_error, btrace_insn_number,
+	btrace_insn_begin, btrace_insn_end, btrace_insn_next, btrace_insn_prev,
+	btrace_find_insn_by_number): Replace function segment pointer with
+	index.
+	(btrace_insn_cmp): Simplify.
+	* btrace.h: (struct btrace_insn_iterator) Rename index to
+	insn_index.  Replace function segment pointer with index into function
+	segment vector.
+	* record-btrace.c (record_btrace_call_history): Replace function
+	segment pointer use with index.
+	(record_btrace_frame_sniffer): Retrieve function call segment through
+	vector.
+	(record_btrace_set_replay): Remove defunc't safety check.
+
+2017-05-30  Tim Wiederhake  <tim.wiederhake@intel.com>
+
 	* btrace.c (btrace_ends_with_single_insn): New function.
 	(btrace_call_get, btrace_call_number, btrace_call_begin,
 	btrace_call_end, btrace_call_next, btrace_call_prev,
diff --git a/gdb/btrace.c b/gdb/btrace.c
index 42ab33d..541d873 100644
--- a/gdb/btrace.c
+++ b/gdb/btrace.c
@@ -2248,8 +2248,8 @@ btrace_insn_get (const struct btrace_insn_iterator *it)
   const struct btrace_function *bfun;
   unsigned int index, end;
 
-  index = it->index;
-  bfun = it->function;
+  index = it->insn_index;
+  bfun = it->btinfo->functions[it->call_index];
 
   /* Check if the iterator points to a gap in the trace.  */
   if (bfun->errcode != 0)
@@ -2268,7 +2268,10 @@ btrace_insn_get (const struct btrace_insn_iterator *it)
 int
 btrace_insn_get_error (const struct btrace_insn_iterator *it)
 {
-  return it->function->errcode;
+  const struct btrace_function *bfun;
+
+  bfun = it->btinfo->functions[it->call_index];
+  return bfun->errcode;
 }
 
 /* See btrace.h.  */
@@ -2276,7 +2279,10 @@ btrace_insn_get_error (const struct btrace_insn_iterator *it)
 unsigned int
 btrace_insn_number (const struct btrace_insn_iterator *it)
 {
-  return it->function->insn_offset + it->index;
+  const struct btrace_function *bfun;
+
+  bfun = it->btinfo->functions[it->call_index];
+  return bfun->insn_offset + it->insn_index;
 }
 
 /* See btrace.h.  */
@@ -2292,8 +2298,8 @@ btrace_insn_begin (struct btrace_insn_iterator *it,
     error (_("No trace."));
 
   it->btinfo = btinfo;
-  it->function = bfun;
-  it->index = 0;
+  it->call_index = 0;
+  it->insn_index = 0;
 }
 
 /* See btrace.h.  */
@@ -2318,8 +2324,8 @@ btrace_insn_end (struct btrace_insn_iterator *it,
     length -= 1;
 
   it->btinfo = btinfo;
-  it->function = bfun;
-  it->index = length;
+  it->call_index = bfun->number - 1;
+  it->insn_index = length;
 }
 
 /* See btrace.h.  */
@@ -2330,9 +2336,9 @@ btrace_insn_next (struct btrace_insn_iterator *it, unsigned int stride)
   const struct btrace_function *bfun;
   unsigned int index, steps;
 
-  bfun = it->function;
+  bfun = it->btinfo->functions[it->call_index];
   steps = 0;
-  index = it->index;
+  index = it->insn_index;
 
   while (stride != 0)
     {
@@ -2398,8 +2404,8 @@ btrace_insn_next (struct btrace_insn_iterator *it, unsigned int stride)
     }
 
   /* Update the iterator.  */
-  it->function = bfun;
-  it->index = index;
+  it->call_index = bfun->number - 1;
+  it->insn_index = index;
 
   return steps;
 }
@@ -2412,9 +2418,9 @@ btrace_insn_prev (struct btrace_insn_iterator *it, unsigned int stride)
   const struct btrace_function *bfun;
   unsigned int index, steps;
 
-  bfun = it->function;
+  bfun = it->btinfo->functions[it->call_index];
   steps = 0;
-  index = it->index;
+  index = it->insn_index;
 
   while (stride != 0)
     {
@@ -2456,8 +2462,8 @@ btrace_insn_prev (struct btrace_insn_iterator *it, unsigned int stride)
     }
 
   /* Update the iterator.  */
-  it->function = bfun;
-  it->index = index;
+  it->call_index = bfun->number - 1;
+  it->insn_index = index;
 
   return steps;
 }
@@ -2468,12 +2474,12 @@ int
 btrace_insn_cmp (const struct btrace_insn_iterator *lhs,
 		 const struct btrace_insn_iterator *rhs)
 {
-  unsigned int lnum, rnum;
+  gdb_assert (lhs->btinfo == rhs->btinfo);
 
-  lnum = btrace_insn_number (lhs);
-  rnum = btrace_insn_number (rhs);
+  if (lhs->call_index != rhs->call_index)
+    return lhs->call_index - rhs->call_index;
 
-  return (int) (lnum - rnum);
+  return lhs->insn_index - rhs->insn_index;
 }
 
 /* See btrace.h.  */
@@ -2522,8 +2528,8 @@ btrace_find_insn_by_number (struct btrace_insn_iterator *it,
     }
 
   it->btinfo = btinfo;
-  it->function = bfun;
-  it->index = number - bfun->insn_offset;
+  it->call_index = bfun->number - 1;
+  it->insn_index = number - bfun->insn_offset;
   return 1;
 }
 
diff --git a/gdb/btrace.h b/gdb/btrace.h
index 8fefc84..9dc92b7 100644
--- a/gdb/btrace.h
+++ b/gdb/btrace.h
@@ -195,12 +195,11 @@ struct btrace_insn_iterator
   /* The branch trace information for this thread.  Will never be NULL.  */
   const struct btrace_thread_info *btinfo;
 
-  /* The branch trace function segment containing the instruction.
-     Will never be NULL.  */
-  const struct btrace_function *function;
+  /* The index of the function segment in BTINFO->FUNCTIONS.  */
+  unsigned int call_index;
 
   /* The index into the function segment's instruction vector.  */
-  unsigned int index;
+  unsigned int insn_index;
 };
 
 /* A branch trace function call iterator.  */
diff --git a/gdb/record-btrace.c b/gdb/record-btrace.c
index 86a4b1e..ec940f65 100644
--- a/gdb/record-btrace.c
+++ b/gdb/record-btrace.c
@@ -1102,7 +1102,7 @@ record_btrace_call_history (struct target_ops *self, int size, int int_flags)
       if (replay != NULL)
 	{
 	  begin.btinfo = btinfo;
-	  begin.index = replay->function->number - 1;
+	  begin.index = replay->call_index;
 	}
       else
 	btrace_call_end (&begin, btinfo);
@@ -1678,7 +1678,7 @@ record_btrace_frame_sniffer (const struct frame_unwind *self,
 
       replay = tp->btrace.replay;
       if (replay != NULL)
-	bfun = replay->function;
+	bfun = replay->btinfo->functions[replay->call_index];
     }
   else
     {
@@ -2691,7 +2691,7 @@ record_btrace_set_replay (struct thread_info *tp,
 
   btinfo = &tp->btrace;
 
-  if (it == NULL || it->function == NULL)
+  if (it == NULL)
     record_btrace_stop_replaying (tp);
   else
     {