-/* Dwarf2 Expression Evaluator
- Copyright 2001, 2002, 2003 Free Software Foundation, Inc.
- Contributed by Daniel Berlin (dan@dberlin.org)
+/* DWARF 2 Expression Evaluator.
+
+ Copyright (C) 2001, 2002, 2003, 2005, 2007, 2008, 2009
+ Free Software Foundation, Inc.
+
+ Contributed by Daniel Berlin <dan@dberlin.org>.
+
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,
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 <http://www.gnu.org/licenses/>. */
#if !defined (DWARF2EXPR_H)
#define DWARF2EXPR_H
number of elements allocated to the stack. */
int stack_len, stack_allocated;
+ /* Target architecture to use for address operations. */
+ struct gdbarch *gdbarch;
+
+ /* Target address size in bytes. */
+ int addr_size;
+
/* 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. LVALP will be set
- to the kind of lval this register is (generally lval_register
- for the current frame's registers or lval_memory for a register
- saved to the stack). For lval_memory ADDRP will be set to the
- saved location of the register. */
- CORE_ADDR (*read_reg) (void *baton, int regnum, enum lval_type *lvalp,
- CORE_ADDR *addrp);
+ /* 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, char *buf, CORE_ADDR addr,
- size_t length);
+ 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, unsigned char **start,
- size_t *length);
+ void (*get_frame_base) (void *baton, gdb_byte **start, size_t *length);
/* Return the thread-local storage address for
DW_OP_GNU_push_tls_address. */
int recursion_depth, max_recursion_depth;
/* Non-zero if the result is in a register. The register number
- will be in REGNUM, and the result will be the contents of the
- register. */
+ will be on the expression stack. */
int in_reg;
- /* If the result is in a register, the register number. */
- int regnum;
+ /* Initialization status of variable: Non-zero if variable has been
+ initialized; zero otherwise. */
+ int initialized;
+
+ /* An array of pieces. PIECES points to its first element;
+ NUM_PIECES is its length.
+
+ Each time DW_OP_piece is executed, we add a new element to the
+ end of this array, recording the current top of the stack, the
+ current in_reg flag, and the size given as the operand to
+ DW_OP_piece. We then pop the top value from the stack, clear the
+ in_reg flag, and resume evaluation.
+
+ The Dwarf spec doesn't say whether DW_OP_piece pops the top value
+ from the stack. We do, ensuring that clients of this interface
+ expecting to see a value left on the top of the stack (say, code
+ evaluating frame base expressions or CFA's specified with
+ DW_CFA_def_cfa_expression) will get an error if the expression
+ actually marks all the values it computes as pieces.
+
+ If an expression never uses DW_OP_piece, num_pieces will be zero.
+ (It would be nice to present these cases as expressions yielding
+ a single piece, with in_reg clear, so that callers need not
+ distinguish between the no-DW_OP_piece and one-DW_OP_piece cases.
+ But expressions with no DW_OP_piece operations have no value to
+ place in a piece's 'size' field; the size comes from the
+ surrounding data. So the two cases need to be handled
+ separately.) */
+ int num_pieces;
+ struct dwarf_expr_piece *pieces;
};
-struct dwarf_expr_context *new_dwarf_expr_context ();
+
+/* A piece of an object, as recorded by DW_OP_piece. */
+struct dwarf_expr_piece
+{
+ /* If IN_REG is zero, then the piece is in memory, and VALUE is its address.
+ If IN_REG is non-zero, then the piece is in a register, and VALUE
+ is the register number. */
+ int in_reg;
+
+ /* This piece's address or register number. */
+ CORE_ADDR value;
+
+ /* The length of the piece, in bytes. */
+ ULONGEST size;
+};
+
+struct dwarf_expr_context *new_dwarf_expr_context (void);
void free_dwarf_expr_context (struct dwarf_expr_context *ctx);
void dwarf_expr_push (struct dwarf_expr_context *ctx, CORE_ADDR value);
CORE_ADDR dwarf_expr_fetch (struct dwarf_expr_context *ctx, int n);
-unsigned char *read_uleb128 (unsigned char *buf, unsigned char *buf_end,
- ULONGEST * r);
-unsigned char *read_sleb128 (unsigned char *buf, unsigned char *buf_end,
- LONGEST * r);
-CORE_ADDR dwarf2_read_address (unsigned char *buf, unsigned char *buf_end,
- int *bytes_read);
+gdb_byte *read_uleb128 (gdb_byte *buf, gdb_byte *buf_end, ULONGEST * r);
+gdb_byte *read_sleb128 (gdb_byte *buf, gdb_byte *buf_end, LONGEST * r);
+CORE_ADDR dwarf2_read_address (struct gdbarch *gdbarch, gdb_byte *buf,
+ gdb_byte *buf_end, int addr_size);
-#endif
+#endif /* dwarf2expr.h */
projects / deliverable / binutils-gdb.git / blobdiff