X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=gdb%2Fframe-unwind.h;h=9079e5d249766574c37e7ab739379cd6653e91f6;hb=ad0d0dfb98677d89891ac83d15c51c1de18dc55a;hp=8d17280fc9afa630293885479d324e299d9bb3ec;hpb=336d1bba0aa5fa96bab6d7fb23317be1374ad151;p=deliverable%2Fbinutils-gdb.git diff --git a/gdb/frame-unwind.h b/gdb/frame-unwind.h index 8d17280fc9..9079e5d249 100644 --- a/gdb/frame-unwind.h +++ b/gdb/frame-unwind.h @@ -1,12 +1,13 @@ /* Definitions for a frame unwinder, for GDB, the GNU debugger. - Copyright 2003 Free Software Foundation, Inc. + Copyright (C) 2003, 2004, 2007, 2008, 2009, 2010 + Free Software Foundation, Inc. This file is part of GDB. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2 of the License, or + the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, @@ -15,25 +16,25 @@ GNU General Public License for more details. You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 59 Temple Place - Suite 330, - Boston, MA 02111-1307, USA. */ + along with this program. If not, see . */ #if !defined (FRAME_UNWIND_H) #define FRAME_UNWIND_H 1 +struct frame_data; struct frame_info; struct frame_id; struct frame_unwind; struct gdbarch; struct regcache; +struct value; #include "frame.h" /* For enum frame_type. */ /* The following unwind functions assume a chain of frames forming the sequence: (outer) prev <-> this <-> next (inner). All the - functions are called with called with the next frame's `struct - frame_info' and and this frame's prologue cache. + functions are called with the next frame's `struct frame_info' + and this frame's prologue cache. THIS frame's register values can be obtained by unwinding NEXT frame's registers (a recursive operation). @@ -42,9 +43,24 @@ struct regcache; as where this frame's prologue stores the previous frame's registers. */ +/* Given THIS frame, take a whiff of its registers (namely + the PC and attributes) and if SELF is the applicable unwinder, + return non-zero. Possibly also initialize THIS_PROLOGUE_CACHE. */ + +typedef int (frame_sniffer_ftype) (const struct frame_unwind *self, + struct frame_info *this_frame, + void **this_prologue_cache); + +/* A default frame sniffer which always accepts the frame. Used by + fallback prologue unwinders. */ + +int default_frame_sniffer (const struct frame_unwind *self, + struct frame_info *this_frame, + void **this_prologue_cache); + /* Assuming the frame chain: (outer) prev <-> this <-> next (inner); - use the NEXT frame, and its register unwind method, to determine - the frame ID of THIS frame. + use THIS frame, and through it the NEXT frame's register unwind + method, to determine the frame ID of THIS frame. A frame ID provides an invariant that can be used to re-identify an instance of a frame. It is a combination of the frame's `base' and @@ -63,16 +79,16 @@ struct regcache; THIS_PROLOGUE_CACHE can be used to share any prolog analysis data with the other unwind methods. Memory for that cache should be - allocated using frame_obstack_zalloc(). */ + allocated using FRAME_OBSTACK_ZALLOC(). */ -typedef void (frame_this_id_ftype) (struct frame_info *next_frame, +typedef void (frame_this_id_ftype) (struct frame_info *this_frame, void **this_prologue_cache, struct frame_id *this_id); /* Assuming the frame chain: (outer) prev <-> this <-> next (inner); - use the NEXT frame, and its register unwind method, to unwind THIS - frame's registers (returning the value of the specified register - REGNUM in the previous frame). + use THIS frame, and implicitly the NEXT frame's register unwind + method, to unwind THIS frame's registers (returning the value of + the specified register REGNUM in the previous frame). Traditionally, THIS frame's registers were unwound by examining THIS frame's function's prologue and identifying which registers @@ -84,30 +100,34 @@ typedef void (frame_this_id_ftype) (struct frame_info *next_frame, register in the previous frame is found in memory at SP+12, and THIS frame's SP can be obtained by unwinding the NEXT frame's SP. - Why not pass in THIS_FRAME? By passing in NEXT frame and THIS - cache, the supplied parameters are consistent with the sibling - function THIS_ID. + This function takes THIS_FRAME as an argument. It can find the + values of registers in THIS frame by calling get_frame_register + (THIS_FRAME), and reinvoke itself to find other registers in the + PREVIOUS frame by calling frame_unwind_register (THIS_FRAME). - Can the code call ``frame_register (get_prev_frame (NEXT_FRAME))''? - Won't the call frame_register (THIS_FRAME) be faster? Well, - ignoring the possability that the previous frame does not yet - exist, the ``frame_register (FRAME)'' function is expanded to - ``frame_register_unwind (get_next_frame (FRAME)'' and hence that - call will expand to ``frame_register_unwind (get_next_frame - (get_prev_frame (NEXT_FRAME)))''. Might as well call - ``frame_register_unwind (NEXT_FRAME)'' directly. + The result is a GDB value object describing the register value. It + may be a lazy reference to memory, a lazy reference to the value of + a register in THIS frame, or a non-lvalue. THIS_PROLOGUE_CACHE can be used to share any prolog analysis data with the other unwind methods. Memory for that cache should be - allocated using frame_obstack_zalloc(). */ + allocated using FRAME_OBSTACK_ZALLOC(). */ + +typedef struct value * (frame_prev_register_ftype) + (struct frame_info *this_frame, void **this_prologue_cache, + int regnum); + +/* Deallocate extra memory associated with the frame cache if any. */ -typedef void (frame_prev_register_ftype) (struct frame_info *next_frame, - void **this_prologue_cache, - int prev_regnum, - int *optimized, - enum lval_type * lvalp, - CORE_ADDR *addrp, - int *realnump, void *valuep); +typedef void (frame_dealloc_cache_ftype) (struct frame_info *self, + void *this_cache); + +/* Assuming the frame chain: (outer) prev <-> this <-> next (inner); + use THIS frame, and implicitly the NEXT frame's register unwind + method, return PREV frame's architecture. */ + +typedef struct gdbarch *(frame_prev_arch_ftype) (struct frame_info *this_frame, + void **this_prologue_cache); struct frame_unwind { @@ -118,24 +138,72 @@ struct frame_unwind here? */ frame_this_id_ftype *this_id; frame_prev_register_ftype *prev_register; + const struct frame_data *unwind_data; + frame_sniffer_ftype *sniffer; + frame_dealloc_cache_ftype *dealloc_cache; + frame_prev_arch_ftype *prev_arch; }; -/* Given the NEXT frame, take a wiff of THIS frame's registers (namely - the PC and attributes) and if it is the applicable unwinder return - the unwind methods, or NULL if it is not. */ - -typedef const struct frame_unwind *(frame_unwind_sniffer_ftype) (struct frame_info *next_frame); +/* Register a frame unwinder, _prepending_ it to the front of the + search list (so it is sniffed before previously registered + unwinders). By using a prepend, later calls can install unwinders + that override earlier calls. This allows, for instance, an OSABI + to install a a more specific sigtramp unwinder that overrides the + traditional brute-force unwinder. */ +extern void frame_unwind_prepend_unwinder (struct gdbarch *gdbarch, + const struct frame_unwind *unwinder); /* Add a frame sniffer to the list. The predicates are polled in the order that they are appended. The initial list contains the dummy frame sniffer. */ -extern void frame_unwind_append_sniffer (struct gdbarch *gdbarch, - frame_unwind_sniffer_ftype *sniffer); +extern void frame_unwind_append_unwinder (struct gdbarch *gdbarch, + const struct frame_unwind *unwinder); + +/* Iterate through sniffers for THIS frame until one returns with an + unwinder implementation. Possibly initialize THIS_CACHE. */ + +extern const struct frame_unwind *frame_unwind_find_by_frame (struct frame_info *this_frame, + void **this_cache); + +/* Helper functions for value-based register unwinding. These return + a (possibly lazy) value of the appropriate type. */ + +/* Return a value which indicates that FRAME did not save REGNUM. */ + +struct value *frame_unwind_got_optimized (struct frame_info *frame, + int regnum); + +/* Return a value which indicates that FRAME copied REGNUM into + register NEW_REGNUM. */ + +struct value *frame_unwind_got_register (struct frame_info *frame, int regnum, + int new_regnum); + +/* Return a value which indicates that FRAME saved REGNUM in memory at + ADDR. */ + +struct value *frame_unwind_got_memory (struct frame_info *frame, int regnum, + CORE_ADDR addr); + +/* Return a value which indicates that FRAME's saved version of + REGNUM has a known constant (computed) value of VAL. */ + +struct value *frame_unwind_got_constant (struct frame_info *frame, int regnum, + ULONGEST val); + +/* Return a value which indicates that FRAME's saved version of + REGNUM has a known constant (computed) value which is stored + inside BUF. */ + +struct value *frame_unwind_got_bytes (struct frame_info *frame, int regnum, + gdb_byte *buf); -/* Iterate through the next frame's sniffers until one returns with an - unwinder implementation. */ +/* Return a value which indicates that FRAME's saved version of REGNUM + has a known constant (computed) value of ADDR. Convert the + CORE_ADDR to a target address if necessary. */ -extern const struct frame_unwind *frame_unwind_find_by_frame (struct frame_info *next_frame); +struct value *frame_unwind_got_address (struct frame_info *frame, int regnum, + CORE_ADDR addr); #endif