/* DWARF 2 Expression Evaluator.
- Copyright (C) 2001, 2002, 2003, 2005, 2007, 2008, 2009, 2010
- Free Software Foundation, Inc.
+ Copyright (C) 2001-2017 Free Software Foundation, Inc.
Contributed by Daniel Berlin <dan@dberlin.org>.
#if !defined (DWARF2EXPR_H)
#define DWARF2EXPR_H
+#include "leb128.h"
+#include "gdbtypes.h"
+
/* The location of a value. */
enum dwarf_value_location
{
DWARF_VALUE_LITERAL,
/* The piece was optimized out. */
- DWARF_VALUE_OPTIMIZED_OUT
+ DWARF_VALUE_OPTIMIZED_OUT,
+
+ /* The piece is an implicit pointer. */
+ DWARF_VALUE_IMPLICIT_POINTER
};
/* The dwarf expression stack. */
struct dwarf_stack_value
{
- ULONGEST value;
+ struct value *value;
/* Non-zero if the piece is in memory and is known to be
on the program's stack. It is always ok to set this to zero.
its current state and its callbacks. */
struct dwarf_expr_context
{
+ dwarf_expr_context ();
+ virtual ~dwarf_expr_context ();
+
+ void push_address (CORE_ADDR value, int in_stack_memory);
+ void eval (const gdb_byte *addr, size_t len);
+ struct value *fetch (int n);
+ CORE_ADDR fetch_address (int n);
+ int fetch_in_stack_memory (int n);
+
/* The stack of values, allocated with xmalloc. */
struct dwarf_stack_value *stack;
/* Target address size in bytes. */
int addr_size;
- /* Offset used to relocate DW_OP_addr argument. */
- CORE_ADDR offset;
-
- /* An opaque argument provided by the caller, which will be passed
- to all of the callback functions. */
- void *baton;
-
- /* Return the value of register number REGNUM. */
- CORE_ADDR (*read_reg) (void *baton, int regnum);
-
- /* Read LENGTH bytes at ADDR into BUF. */
- void (*read_mem) (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t length);
-
- /* Return the location expression for the frame base attribute, in
- START and LENGTH. The result must be live until the current
- expression evaluation is complete. */
- void (*get_frame_base) (void *baton, const gdb_byte **start, size_t *length);
-
- /* Return the CFA for the frame. */
- CORE_ADDR (*get_frame_cfa) (void *baton);
+ /* DW_FORM_ref_addr size in bytes. If -1 DWARF is executed from a frame
+ context and operations depending on DW_FORM_ref_addr are not allowed. */
+ int ref_addr_size;
- /* Return the thread-local storage address for
- DW_OP_GNU_push_tls_address. */
- CORE_ADDR (*get_tls_address) (void *baton, CORE_ADDR offset);
-
- /* Execute DW_AT_location expression for the DWARF expression subroutine in
- the DIE at DIE_OFFSET in the CU from CTX. Do not touch STACK while it
- being passed to and returned from the called DWARF subroutine. */
- void (*dwarf_call) (struct dwarf_expr_context *ctx, size_t die_offset);
-
-#if 0
- /* Not yet implemented. */
-
- /* Return the `object address' for DW_OP_push_object_address. */
- CORE_ADDR (*get_object_address) (void *baton);
-#endif
+ /* Offset used to relocate DW_OP_addr and DW_OP_GNU_addr_index arguments. */
+ CORE_ADDR offset;
/* The current depth of dwarf expression recursion, via DW_OP_call*,
DW_OP_fbreg, DW_OP_push_object_address, etc., and the maximum
/* Location of the value. */
enum dwarf_value_location location;
- /* For VALUE_LITERAL, a the current literal value's length and
- data. */
+ /* For DWARF_VALUE_LITERAL, the current literal value's length and
+ data. For DWARF_VALUE_IMPLICIT_POINTER, LEN is the offset of the
+ target DIE of sect_offset kind. */
ULONGEST len;
const gdb_byte *data;
two cases need to be handled separately.) */
int num_pieces;
struct dwarf_expr_piece *pieces;
+
+ /* Return the value of register number REGNUM (a DWARF register number),
+ read as an address. */
+ virtual CORE_ADDR read_addr_from_reg (int regnum) = 0;
+
+ /* Return a value of type TYPE, stored in register number REGNUM
+ of the frame associated to the given BATON.
+
+ REGNUM is a DWARF register number. */
+ virtual struct value *get_reg_value (struct type *type, int regnum) = 0;
+
+ /* Read LENGTH bytes at ADDR into BUF. */
+ virtual void read_mem (gdb_byte *buf, CORE_ADDR addr, size_t length) = 0;
+
+ /* Return the location expression for the frame base attribute, in
+ START and LENGTH. The result must be live until the current
+ expression evaluation is complete. */
+ virtual void get_frame_base (const gdb_byte **start, size_t *length) = 0;
+
+ /* Return the CFA for the frame. */
+ virtual CORE_ADDR get_frame_cfa () = 0;
+
+ /* Return the PC for the frame. */
+ virtual CORE_ADDR get_frame_pc ()
+ {
+ error (_("%s is invalid in this context"), "DW_OP_implicit_pointer");
+ }
+
+ /* Return the thread-local storage address for
+ DW_OP_GNU_push_tls_address or DW_OP_form_tls_address. */
+ virtual CORE_ADDR get_tls_address (CORE_ADDR offset) = 0;
+
+ /* Execute DW_AT_location expression for the DWARF expression
+ subroutine in the DIE at DIE_OFFSET in the CU. Do not touch
+ STACK while it being passed to and returned from the called DWARF
+ subroutine. */
+ virtual void dwarf_call (cu_offset die_offset) = 0;
+
+ /* Return the base type given by the indicated DIE. This can throw
+ an exception if the DIE is invalid or does not represent a base
+ type. SIZE is non-zero if this function should verify that the
+ resulting type has the correct size. */
+ virtual struct type *get_base_type (cu_offset die, int size)
+ {
+ /* Anything will do. */
+ return builtin_type (this->gdbarch)->builtin_int;
+ }
+
+ /* Push on DWARF stack an entry evaluated for DW_TAG_call_site's
+ parameter matching KIND and KIND_U at the caller of specified BATON.
+ If DEREF_SIZE is not -1 then use DW_AT_call_data_value instead of
+ DW_AT_call_value. */
+ virtual void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind,
+ union call_site_parameter_u kind_u,
+ int deref_size) = 0;
+
+ /* Return the address indexed by DW_OP_GNU_addr_index.
+ This can throw an exception if the index is out of range. */
+ virtual CORE_ADDR get_addr_index (unsigned int index) = 0;
+
+ /* Return the `object address' for DW_OP_push_object_address. */
+ virtual CORE_ADDR get_object_address () = 0;
+
+private:
+
+ struct type *address_type () const;
+ void grow_stack (size_t need);
+ void push (struct value *value, int in_stack_memory);
+ int stack_empty_p () const;
+ void add_piece (ULONGEST size, ULONGEST offset);
+ void execute_stack_op (const gdb_byte *op_ptr, const gdb_byte *op_end);
+ void pop ();
};
int in_stack_memory;
} mem;
- /* The piece's register number or literal value, for
- DWARF_VALUE_REGISTER or DWARF_VALUE_STACK pieces. */
- ULONGEST value;
+ /* The piece's register number, for DWARF_VALUE_REGISTER pieces. */
+ int regno;
+
+ /* The piece's literal value, for DWARF_VALUE_STACK pieces. */
+ struct value *value;
struct
{
/* The length of the available data. */
ULONGEST length;
} literal;
+
+ /* Used for DWARF_VALUE_IMPLICIT_POINTER. */
+ struct
+ {
+ /* The referent DIE from DW_OP_implicit_pointer. */
+ sect_offset die;
+ /* The byte offset into the resulting data. */
+ LONGEST offset;
+ } ptr;
} v;
/* The length of the piece, in bits. */
ULONGEST offset;
};
-struct dwarf_expr_context *new_dwarf_expr_context (void);
-void free_dwarf_expr_context (struct dwarf_expr_context *ctx);
-struct cleanup *
- make_cleanup_free_dwarf_expr_context (struct dwarf_expr_context *ctx);
+void dwarf_expr_require_composition (const gdb_byte *, const gdb_byte *,
+ const char *);
+
+int dwarf_block_to_dwarf_reg (const gdb_byte *buf, const gdb_byte *buf_end);
-void dwarf_expr_push (struct dwarf_expr_context *ctx, ULONGEST value,
- int in_stack_memory);
-void dwarf_expr_pop (struct dwarf_expr_context *ctx);
-void dwarf_expr_eval (struct dwarf_expr_context *ctx, const gdb_byte *addr,
- size_t len);
-ULONGEST dwarf_expr_fetch (struct dwarf_expr_context *ctx, int n);
-CORE_ADDR dwarf_expr_fetch_address (struct dwarf_expr_context *ctx, int n);
-int dwarf_expr_fetch_in_stack_memory (struct dwarf_expr_context *ctx, int n);
+int dwarf_block_to_dwarf_reg_deref (const gdb_byte *buf,
+ const gdb_byte *buf_end,
+ CORE_ADDR *deref_size_return);
+int dwarf_block_to_fb_offset (const gdb_byte *buf, const gdb_byte *buf_end,
+ CORE_ADDR *fb_offset_return);
-const gdb_byte *read_uleb128 (const gdb_byte *buf, const gdb_byte *buf_end,
- ULONGEST * r);
-const gdb_byte *read_sleb128 (const gdb_byte *buf, const gdb_byte *buf_end,
- LONGEST * r);
+int dwarf_block_to_sp_offset (struct gdbarch *gdbarch, const gdb_byte *buf,
+ const gdb_byte *buf_end,
+ CORE_ADDR *sp_offset_return);
-const char *dwarf_stack_op_name (unsigned int, int);
+/* Wrappers around the leb128 reader routines to simplify them for our
+ purposes. */
-void dwarf_expr_require_composition (const gdb_byte *, const gdb_byte *,
- const char *);
+static inline const gdb_byte *
+gdb_read_uleb128 (const gdb_byte *buf, const gdb_byte *buf_end,
+ uint64_t *r)
+{
+ size_t bytes_read = read_uleb128_to_uint64 (buf, buf_end, r);
+
+ if (bytes_read == 0)
+ return NULL;
+ return buf + bytes_read;
+}
+
+static inline const gdb_byte *
+gdb_read_sleb128 (const gdb_byte *buf, const gdb_byte *buf_end,
+ int64_t *r)
+{
+ size_t bytes_read = read_sleb128_to_int64 (buf, buf_end, r);
+
+ if (bytes_read == 0)
+ return NULL;
+ return buf + bytes_read;
+}
+
+static inline const gdb_byte *
+gdb_skip_leb128 (const gdb_byte *buf, const gdb_byte *buf_end)
+{
+ size_t bytes_read = skip_leb128 (buf, buf_end);
+
+ if (bytes_read == 0)
+ return NULL;
+ return buf + bytes_read;
+}
+
+extern const gdb_byte *safe_read_uleb128 (const gdb_byte *buf,
+ const gdb_byte *buf_end,
+ uint64_t *r);
+
+extern const gdb_byte *safe_read_sleb128 (const gdb_byte *buf,
+ const gdb_byte *buf_end,
+ int64_t *r);
+
+extern const gdb_byte *safe_skip_leb128 (const gdb_byte *buf,
+ const gdb_byte *buf_end);
#endif /* dwarf2expr.h */