struct symtab_and_line;
struct frame_unwind;
+struct frame_base;
struct block;
/* A legacy unwinder to prop up architectures using the old style
extern void find_frame_sal (struct frame_info *frame,
struct symtab_and_line *sal);
-/* Return the frame address from FI. Except in the machine-dependent
- *FRAME* macros, a frame address has no defined meaning other than
- as a magic cookie which identifies a frame over calls to the
- inferior (um, SEE NOTE BELOW). The only known exception is
- inferior.h (DEPRECATED_PC_IN_CALL_DUMMY) [ON_STACK]; see comments
- there. You cannot assume that a frame address contains enough
- information to reconstruct the frame; if you want more than just to
- identify the frame (e.g. be able to fetch variables relative to
- that frame), then save the whole struct frame_info (and the next
- struct frame_info, since the latter is used for fetching variables
- on some machines) (um, again SEE NOTE BELOW).
-
- NOTE: cagney/2002-11-18: Actually, the frame address isn't
- sufficient for identifying a frame, and the counter examples are
- wrong!
-
- Code that needs to (re)identify a frame must use get_frame_id() and
- frame_find_by_id() (and in the future, a frame_compare() function
- instead of INNER_THAN()). Two reasons: an architecture (e.g.,
- ia64) can have more than one frame address (due to multiple stack
- pointers) (frame ID is going to be expanded to accomodate this);
- successive frameless function calls can only be differientated by
- comparing both the frame's base and the frame's enclosing function
- (frame_find_by_id() is going to be modified to perform this test).
-
- The generic dummy frame version of DEPRECATED_PC_IN_CALL_DUMMY() is
- able to identify a dummy frame using only the PC value. So the
- frame address is not needed. In fact, most
- DEPRECATED_PC_IN_CALL_DUMMY() calls now pass zero as the frame/sp
- values as the caller knows that those values won't be used. Once
- all architectures are using generic dummy frames,
- DEPRECATED_PC_IN_CALL_DUMMY() can drop the sp/frame parameters.
- When it comes to finding a dummy frame, the next frame's frame ID
- (with out duing an unwind) can be used (ok, could if it wasn't for
- the need to change the way the PPC defined frame base in a strange
- way).
-
- Modern architectures should be using something like dwarf2's
- location expression to describe where a variable lives. Such
- expressions specify their own debug info centric frame address.
- Consequently, a generic frame address is pretty meaningless. */
+/* Return the frame base (what ever that is) (DEPRECATED).
+
+ Old code was trying to use this single method for two conflicting
+ purposes. Such code needs to be updated to use either of:
+
+ get_frame_id: A low level frame unique identifier, that consists of
+ both a stack and a function address, that can be used to uniquely
+ identify a frame. This value is determined by the frame's
+ low-level unwinder, the stack part [typically] being the
+ top-of-stack of the previous frame, and the function part being the
+ function's start address. Since the correct identification of a
+ frameless function requires both the a stack and function address,
+ the old get_frame_base method was not sufficient.
+
+ get_frame_base_address: get_frame_locals_address:
+ get_frame_args_address: A set of high-level debug-info dependant
+ addresses that fall within the frame. These addresses almost
+ certainly will not match the stack address part of a frame ID (as
+ returned by get_frame_base). */
extern CORE_ADDR get_frame_base (struct frame_info *);
FI is NULL, return the null_frame_id. */
extern struct frame_id get_frame_id (struct frame_info *fi);
+/* Assuming that a frame is `normal', return its base-address, or 0 if
+ the information isn't available. NOTE: This address is really only
+ meaningful to the frame's high-level debug info. */
+extern CORE_ADDR get_frame_base_address (struct frame_info *);
+
+/* Assuming that a frame is `normal', return the address of the first
+ local variable, or 0 if the information isn't available. NOTE:
+ This address is really only meaningful to the frame's high-level
+ debug info. Typically, the argument and locals share a single
+ base-address. */
+extern CORE_ADDR get_frame_locals_address (struct frame_info *);
+
+/* Assuming that a frame is `normal', return the address of the first
+ parameter, or 0 if that information isn't available. NOTE: This
+ address is really only meaningful to the frame's high-level debug
+ info. Typically, the argument and locals share a single
+ base-address. */
+extern CORE_ADDR get_frame_args_address (struct frame_info *);
+
/* The frame's level: 0 for innermost, 1 for its caller, ...; or -1
for an invalid frame). */
extern int frame_relative_level (struct frame_info *fi);
related unwind data. */
struct context *context;
- /* Prologue cache shared between the unwind functions. See
- "frame-unwind.h" for more information. */
+ /* The frame's low-level unwinder and corresponding cache. The
+ low-level unwinder is responsible for unwinding register values
+ for the previous frame. The low-level unwind methods are
+ selected based on the presence, or otherwize, of register
+ unwind information such as CFI. */
void *prologue_cache;
-
- /* The frame's unwinder. */
const struct frame_unwind *unwind;
/* Cached copy of the previous frame's resume address. */
int id_p;
struct frame_id id;
+ /* The frame's high-level base methods, and corresponding cache.
+ The high level base methods are selected based on the frame's
+ debug info. */
+ const struct frame_base *base;
+ void *base_cache;
+
/* Pointers to the next (down, inner, younger) and previous (up,
outer, older) frame_info's in the frame cache. */
struct frame_info *next; /* down, inner, younger */
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