This is the second step of making frame_info_ptr automatic, reinflate on
demand whenever trying to obtain the wrapper frame_info pointer, either
through the get method or operator->. Make the reinflate method
private, it is used as a convenience method in those two.
Add an "is_null" method, because it is often needed to know whether the
frame_info_ptr wraps an frame_info or is empty.
Make m_ptr mutable, so that it's possible to reinflate const
frame_info_ptr objects. Whether m_ptr is nullptr or not does not change
the logical state of the object, because we re-create it on demand. I
believe this is the right use case for mutable.
Change-Id: Icb0552d0035e227f81eb3c121d8a9bb2f9d25794
---
gdb/frame-info.c | 8 ++++----
gdb/frame-info.h | 45 ++++++++++++++++++++++++++++++-------------
gdb/infcmd.c | 1 -
gdb/mi/mi-cmd-stack.c | 1 -
gdb/stack.c | 6 ------
5 files changed, 36 insertions(+), 25 deletions(-)
@@ -48,8 +48,8 @@ frame_info_ptr::frame_info_ptr (struct frame_info *ptr)
/* See frame-info-ptr.h. */
-void
-frame_info_ptr::reinflate ()
+frame_info *
+frame_info_ptr::reinflate () const
{
/* Ensure we have a valid frame level (sentinel frame or above), indicating
prepare_reinflate was called. */
@@ -58,7 +58,7 @@ frame_info_ptr::reinflate ()
if (m_ptr != nullptr)
{
/* The frame_info wasn't invalidated, no need to reinflate. */
- return;
+ return m_ptr;
}
/* Frame #0 needs special handling, see comment in select_frame. */
@@ -77,6 +77,7 @@ frame_info_ptr::reinflate ()
}
gdb_assert (m_ptr != nullptr);
+ return m_ptr;
}
#if GDB_SELF_TEST
@@ -97,7 +98,6 @@ test_user_created_frame ()
SELF_CHECK (id.code_addr == 0x5678);
reinit_frame_cache ();
- frame.reinflate ();
id = get_frame_id (frame);
SELF_CHECK (id.stack_status == FID_STACK_VALID);
@@ -107,29 +107,38 @@ class frame_info_ptr : public intrusive_list_node<frame_info_ptr>
}
frame_info *operator-> () const
- {
- return m_ptr;
- }
+ { return this->reinflate (); }
/* Fetch the underlying pointer. Note that new code should
generally not use this -- avoid it if at all possible. */
frame_info *get () const
{
- return m_ptr;
+ if (this->is_null ())
+ return nullptr;
+
+ return this->reinflate ();
}
+ /* Return true if this object is empty (does not wrap a frame_info
+ object). */
+
+ bool is_null () const
+ {
+ return m_cached_level == this->invalid_level;
+ };
+
/* This exists for compatibility with pre-existing code that checked
a "frame_info *" using "!". */
bool operator! () const
{
- return m_ptr == nullptr;
+ return this->is_null ();
}
/* This exists for compatibility with pre-existing code that checked
a "frame_info *" like "if (ptr)". */
explicit operator bool () const
{
- return m_ptr != nullptr;
+ return !this->is_null ();
}
/* Invalidate this pointer. */
@@ -138,17 +147,18 @@ class frame_info_ptr : public intrusive_list_node<frame_info_ptr>
m_ptr = nullptr;
}
- /* Use the cached frame_id to reinflate the pointer. */
- void reinflate ();
-
private:
/* We sometimes need to construct frame_info_ptr objects around the
sentinel_frame, which has level -1. Therefore, make the invalid frame
level value -2. */
static constexpr int invalid_level = -2;
+ /* Use the cached frame level and id to reinflate the pointer, and return
+ it. */
+ frame_info *reinflate () const;
+
/* The underlying pointer. */
- frame_info *m_ptr = nullptr;
+ mutable frame_info *m_ptr = nullptr;
/* The frame_id of the underlying pointer.
@@ -173,37 +183,46 @@ class frame_info_ptr : public intrusive_list_node<frame_info_ptr>
static inline bool
operator== (const frame_info *self, const frame_info_ptr &other)
{
+ if (self == nullptr || other.is_null ())
+ return self == nullptr && other.is_null ();
+
return self == other.get ();
}
static inline bool
operator== (const frame_info_ptr &self, const frame_info_ptr &other)
{
+ if (self.is_null () || other.is_null ())
+ return self.is_null () && other.is_null ();
+
return self.get () == other.get ();
}
static inline bool
operator== (const frame_info_ptr &self, const frame_info *other)
{
+ if (self.is_null () || other == nullptr)
+ return self.is_null () && other == nullptr;
+
return self.get () == other;
}
static inline bool
operator!= (const frame_info *self, const frame_info_ptr &other)
{
- return self != other.get ();
+ return !(self == other);
}
static inline bool
operator!= (const frame_info_ptr &self, const frame_info_ptr &other)
{
- return self.get () != other.get ();
+ return !(self == other);
}
static inline bool
operator!= (const frame_info_ptr &self, const frame_info *other)
{
- return self.get () != other;
+ return !(self == other);
}
#endif /* GDB_FRAME_INFO_H */
@@ -1917,7 +1917,6 @@ finish_command (const char *arg, int from_tty)
print_stack_frame (callee_frame, 1, LOCATION, 0);
}
- frame.reinflate ();
if (execution_direction == EXEC_REVERSE)
finish_backward (sm);
@@ -180,7 +180,6 @@ mi_cmd_stack_list_frames (const char *command, char **argv, int argc)
If args is 0, don't print the arguments. */
print_frame_info (user_frame_print_options,
fi, 1, LOC_AND_ADDRESS, 0 /* args */, 0);
- fi.reinflate ();
}
}
}
@@ -367,7 +367,6 @@ print_stack_frame (frame_info_ptr frame, int print_level,
print_frame_info (user_frame_print_options,
frame, print_level, print_what, 1 /* print_args */,
set_current_sal);
- frame.reinflate ();
if (set_current_sal)
set_current_sal_from_frame (frame);
}
@@ -903,7 +902,6 @@ print_frame_args (const frame_print_options &fp_opts,
}
first = 0;
- frame.reinflate ();
}
}
@@ -1173,7 +1171,6 @@ print_frame_info (const frame_print_options &fp_opts,
print_source_lines (sal.symtab, sal.line, sal.line + 1, 0);
}
- frame.reinflate ();
/* If disassemble-next-line is set to on and there is line debug
messages, output assembly codes for next line. */
@@ -1676,8 +1673,6 @@ info_frame_command_core (frame_info_ptr fi, bool selected_frame_p)
print_frame_args (user_frame_print_options,
func, fi, numargs, gdb_stdout);
- fi.reinflate ();
-
gdb_puts ("\n");
}
}
@@ -2077,7 +2072,6 @@ backtrace_command_1 (const frame_print_options &fp_opts,
print_frame_local_vars (fi, false, NULL, NULL, 1, gdb_stdout);
/* Save the last frame to check for error conditions. */
- fi.reinflate ();
trailing = fi;
}