-/* Dwarf2 Expression Evaluator
- Copyright 2001, 2002, 2003 Free Software Foundation, Inc.
+/* 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/>. */
#include "defs.h"
#include "symtab.h"
#include "gdbcore.h"
#include "elf/dwarf2.h"
#include "dwarf2expr.h"
+#include "gdb_assert.h"
/* Local prototypes. */
static void execute_stack_op (struct dwarf_expr_context *,
- unsigned char *, unsigned char *);
+ gdb_byte *, gdb_byte *);
+static struct type *unsigned_address_type (int);
/* Create a new context for the expression evaluator. */
struct dwarf_expr_context *
-new_dwarf_expr_context ()
+new_dwarf_expr_context (void)
{
struct dwarf_expr_context *retval;
retval = xcalloc (1, sizeof (struct dwarf_expr_context));
- retval->stack_len = 10;
- retval->stack = xmalloc (10 * sizeof (CORE_ADDR));
+ retval->stack_len = 0;
+ retval->stack_allocated = 10;
+ retval->stack = xmalloc (retval->stack_allocated * sizeof (CORE_ADDR));
+ retval->num_pieces = 0;
+ retval->pieces = 0;
+ retval->max_recursion_depth = 0x100;
return retval;
}
free_dwarf_expr_context (struct dwarf_expr_context *ctx)
{
xfree (ctx->stack);
+ xfree (ctx->pieces);
xfree (ctx);
}
{
if (ctx->stack_len + need > ctx->stack_allocated)
{
- size_t templen = ctx->stack_len * 2;
- while (templen < (ctx->stack_len + need))
- templen *= 2;
+ size_t newlen = ctx->stack_len + need + 10;
ctx->stack = xrealloc (ctx->stack,
- templen * sizeof (CORE_ADDR));
- ctx->stack_allocated = templen;
+ newlen * sizeof (CORE_ADDR));
+ ctx->stack_allocated = newlen;
}
}
dwarf_expr_pop (struct dwarf_expr_context *ctx)
{
if (ctx->stack_len <= 0)
- error ("dwarf expression stack underflow");
+ error (_("dwarf expression stack underflow"));
ctx->stack_len--;
}
CORE_ADDR
dwarf_expr_fetch (struct dwarf_expr_context *ctx, int n)
{
- if (ctx->stack_len < n)
- error ("Asked for position %d of stack, stack only has %d elements on it\n",
+ if (ctx->stack_len <= n)
+ error (_("Asked for position %d of stack, stack only has %d elements on it."),
n, ctx->stack_len);
return ctx->stack[ctx->stack_len - (1 + n)];
}
+/* Add a new piece to CTX's piece list. */
+static void
+add_piece (struct dwarf_expr_context *ctx,
+ int in_reg, CORE_ADDR value, ULONGEST size)
+{
+ struct dwarf_expr_piece *p;
+
+ ctx->num_pieces++;
+
+ if (ctx->pieces)
+ ctx->pieces = xrealloc (ctx->pieces,
+ (ctx->num_pieces
+ * sizeof (struct dwarf_expr_piece)));
+ else
+ ctx->pieces = xmalloc (ctx->num_pieces
+ * sizeof (struct dwarf_expr_piece));
+
+ p = &ctx->pieces[ctx->num_pieces - 1];
+ p->in_reg = in_reg;
+ p->value = value;
+ p->size = size;
+}
+
/* Evaluate the expression at ADDR (LEN bytes long) using the context
CTX. */
void
-dwarf_expr_eval (struct dwarf_expr_context *ctx, unsigned char *addr,
- size_t len)
+dwarf_expr_eval (struct dwarf_expr_context *ctx, gdb_byte *addr, size_t len)
{
+ int old_recursion_depth = ctx->recursion_depth;
+
execute_stack_op (ctx, addr, addr + len);
+
+ /* CTX RECURSION_DEPTH becomes invalid if an exception was thrown here. */
+
+ gdb_assert (ctx->recursion_depth == old_recursion_depth);
}
/* Decode the unsigned LEB128 constant at BUF into the variable pointed to
by R, and return the new value of BUF. Verify that it doesn't extend
past BUF_END. */
-unsigned char *
-read_uleb128 (unsigned char *buf, unsigned char *buf_end, ULONGEST * r)
+gdb_byte *
+read_uleb128 (gdb_byte *buf, gdb_byte *buf_end, ULONGEST * r)
{
unsigned shift = 0;
ULONGEST result = 0;
- unsigned char byte;
+ gdb_byte byte;
while (1)
{
if (buf >= buf_end)
- error ("read_uleb128: Corrupted DWARF expression.");
+ error (_("read_uleb128: Corrupted DWARF expression."));
byte = *buf++;
result |= (byte & 0x7f) << shift;
by R, and return the new value of BUF. Verify that it doesn't extend
past BUF_END. */
-unsigned char *
-read_sleb128 (unsigned char *buf, unsigned char *buf_end, LONGEST * r)
+gdb_byte *
+read_sleb128 (gdb_byte *buf, gdb_byte *buf_end, LONGEST * r)
{
unsigned shift = 0;
LONGEST result = 0;
- unsigned char byte;
+ gdb_byte byte;
while (1)
{
if (buf >= buf_end)
- error ("read_sleb128: Corrupted DWARF expression.");
+ error (_("read_sleb128: Corrupted DWARF expression."));
byte = *buf++;
result |= (byte & 0x7f) << shift;
return buf;
}
-/* Read an address from BUF, and verify that it doesn't extend past
- BUF_END. The address is returned, and *BYTES_READ is set to the
- number of bytes read from BUF. */
+/* Read an address of size ADDR_SIZE from BUF, and verify that it
+ doesn't extend past BUF_END. */
-static CORE_ADDR
-read_address (unsigned char *buf, unsigned char *buf_end, int *bytes_read)
+CORE_ADDR
+dwarf2_read_address (struct gdbarch *gdbarch, gdb_byte *buf,
+ gdb_byte *buf_end, int addr_size)
{
CORE_ADDR result;
- if (buf_end - buf < TARGET_ADDR_BIT / TARGET_CHAR_BIT)
- error ("read_address: Corrupted DWARF expression.");
+ if (buf_end - buf < addr_size)
+ error (_("dwarf2_read_address: Corrupted DWARF expression."));
+
+ /* For most architectures, calling extract_unsigned_integer() alone
+ is sufficient for extracting an address. However, some
+ architectures (e.g. MIPS) use signed addresses and using
+ extract_unsigned_integer() will not produce a correct
+ result. Make sure we invoke gdbarch_integer_to_address()
+ for those architectures which require it.
- *bytes_read = TARGET_ADDR_BIT / TARGET_CHAR_BIT;
- result = extract_address (buf, TARGET_ADDR_BIT / TARGET_CHAR_BIT);
- return result;
+ The use of `unsigned_address_type' in the code below refers to
+ the type of buf and has no bearing on the signedness of the
+ address being returned. */
+
+ if (gdbarch_integer_to_address_p (gdbarch))
+ return gdbarch_integer_to_address
+ (gdbarch, unsigned_address_type (addr_size), buf);
+
+ return extract_unsigned_integer (buf, addr_size);
}
-/* Return the type of an address, for unsigned arithmetic. */
+/* Return the type of an address of size ADDR_SIZE,
+ for unsigned arithmetic. */
static struct type *
-unsigned_address_type (void)
+unsigned_address_type (int addr_size)
{
- switch (TARGET_ADDR_BIT / TARGET_CHAR_BIT)
+ switch (addr_size)
{
case 2:
return builtin_type_uint16;
return builtin_type_uint64;
default:
internal_error (__FILE__, __LINE__,
- "Unsupported address size.\n");
+ _("Unsupported address size.\n"));
}
}
-/* Return the type of an address, for signed arithmetic. */
+/* Return the type of an address of size ADDR_SIZE,
+ for signed arithmetic. */
static struct type *
-signed_address_type (void)
+signed_address_type (int addr_size)
{
- switch (TARGET_ADDR_BIT / TARGET_CHAR_BIT)
+ switch (addr_size)
{
case 2:
return builtin_type_int16;
return builtin_type_int64;
default:
internal_error (__FILE__, __LINE__,
- "Unsupported address size.\n");
+ _("Unsupported address size.\n"));
}
}
\f
evaluate the expression between OP_PTR and OP_END. */
static void
-execute_stack_op (struct dwarf_expr_context *ctx, unsigned char *op_ptr,
- unsigned char *op_end)
+execute_stack_op (struct dwarf_expr_context *ctx,
+ gdb_byte *op_ptr, gdb_byte *op_end)
{
+ ctx->in_reg = 0;
+ ctx->initialized = 1; /* Default is initialized. */
+
+ if (ctx->recursion_depth > ctx->max_recursion_depth)
+ error (_("DWARF-2 expression error: Loop detected (%d)."),
+ ctx->recursion_depth);
+ ctx->recursion_depth++;
+
while (op_ptr < op_end)
{
enum dwarf_location_atom op = *op_ptr++;
- CORE_ADDR result, memaddr;
+ CORE_ADDR result;
ULONGEST uoffset, reg;
LONGEST offset;
- int bytes_read;
- enum lval_type expr_lval;
-
- ctx->in_reg = 0;
switch (op)
{
break;
case DW_OP_addr:
- result = read_address (op_ptr, op_end, &bytes_read);
- op_ptr += bytes_read;
+ result = dwarf2_read_address (ctx->gdbarch,
+ op_ptr, op_end, ctx->addr_size);
+ op_ptr += ctx->addr_size;
break;
case DW_OP_const1u:
case DW_OP_reg29:
case DW_OP_reg30:
case DW_OP_reg31:
- /* NOTE: in the presence of DW_OP_piece this check is incorrect. */
- if (op_ptr != op_end)
- error ("DWARF-2 expression error: DW_OP_reg operations must be "
- "used alone.");
+ if (op_ptr != op_end
+ && *op_ptr != DW_OP_piece
+ && *op_ptr != DW_OP_GNU_uninit)
+ error (_("DWARF-2 expression error: DW_OP_reg operations must be "
+ "used either alone or in conjuction with DW_OP_piece."));
- /* FIXME drow/2003-02-21: This call to read_reg could be pushed
- into the evaluator's caller by changing the semantics for in_reg.
- Then we wouldn't need to return an lval_type and a memaddr. */
- result = (ctx->read_reg) (ctx->baton, op - DW_OP_reg0, &expr_lval,
- &memaddr);
-
- if (expr_lval == lval_register)
- {
- ctx->regnum = op - DW_OP_reg0;
- ctx->in_reg = 1;
- }
- else
- result = memaddr;
+ result = op - DW_OP_reg0;
+ ctx->in_reg = 1;
break;
case DW_OP_regx:
op_ptr = read_uleb128 (op_ptr, op_end, ®);
- if (op_ptr != op_end)
- error ("DWARF-2 expression error: DW_OP_reg operations must be "
- "used alone.");
-
- result = (ctx->read_reg) (ctx->baton, reg, &expr_lval, &memaddr);
-
- if (expr_lval == lval_register)
- {
- ctx->regnum = reg;
- ctx->in_reg = 1;
- }
- else
- result = memaddr;
+ if (op_ptr != op_end && *op_ptr != DW_OP_piece)
+ error (_("DWARF-2 expression error: DW_OP_reg operations must be "
+ "used either alone or in conjuction with DW_OP_piece."));
+ result = reg;
+ ctx->in_reg = 1;
break;
case DW_OP_breg0:
case DW_OP_breg31:
{
op_ptr = read_sleb128 (op_ptr, op_end, &offset);
- result = (ctx->read_reg) (ctx->baton, op - DW_OP_breg0,
- &expr_lval, &memaddr);
+ result = (ctx->read_reg) (ctx->baton, op - DW_OP_breg0);
result += offset;
}
break;
{
op_ptr = read_uleb128 (op_ptr, op_end, ®);
op_ptr = read_sleb128 (op_ptr, op_end, &offset);
- result = (ctx->read_reg) (ctx->baton, reg, &expr_lval, &memaddr);
+ result = (ctx->read_reg) (ctx->baton, reg);
result += offset;
}
break;
case DW_OP_fbreg:
{
- unsigned char *datastart;
+ gdb_byte *datastart;
size_t datalen;
unsigned int before_stack_len;
afterwards, effectively erasing whatever the recursive
call put there. */
before_stack_len = ctx->stack_len;
+ /* FIXME: cagney/2003-03-26: This code should be using
+ get_frame_base_address(), and then implement a dwarf2
+ specific this_base method. */
(ctx->get_frame_base) (ctx->baton, &datastart, &datalen);
dwarf_expr_eval (ctx, datastart, datalen);
result = dwarf_expr_fetch (ctx, 0);
- if (! ctx->in_reg)
- {
- char *buf = alloca (TARGET_ADDR_BIT / TARGET_CHAR_BIT);
- int bytes_read;
-
- (ctx->read_mem) (ctx->baton, buf, result,
- TARGET_ADDR_BIT / TARGET_CHAR_BIT);
- result = read_address (buf,
- buf + TARGET_ADDR_BIT / TARGET_CHAR_BIT,
- &bytes_read);
- }
+ if (ctx->in_reg)
+ result = (ctx->read_reg) (ctx->baton, result);
result = result + offset;
ctx->stack_len = before_stack_len;
ctx->in_reg = 0;
offset = *op_ptr++;
result = dwarf_expr_fetch (ctx, offset);
break;
+
+ case DW_OP_swap:
+ {
+ CORE_ADDR t1, t2;
+
+ if (ctx->stack_len < 2)
+ error (_("Not enough elements for DW_OP_swap. Need 2, have %d."),
+ ctx->stack_len);
+ t1 = ctx->stack[ctx->stack_len - 1];
+ t2 = ctx->stack[ctx->stack_len - 2];
+ ctx->stack[ctx->stack_len - 1] = t2;
+ ctx->stack[ctx->stack_len - 2] = t1;
+ goto no_push;
+ }
case DW_OP_over:
result = dwarf_expr_fetch (ctx, 1);
CORE_ADDR t1, t2, t3;
if (ctx->stack_len < 3)
- error ("Not enough elements for DW_OP_rot. Need 3, have %d\n",
+ error (_("Not enough elements for DW_OP_rot. Need 3, have %d."),
ctx->stack_len);
t1 = ctx->stack[ctx->stack_len - 1];
t2 = ctx->stack[ctx->stack_len - 2];
{
case DW_OP_deref:
{
- char *buf = alloca (TARGET_ADDR_BIT / TARGET_CHAR_BIT);
- int bytes_read;
-
- (ctx->read_mem) (ctx->baton, buf, result,
- TARGET_ADDR_BIT / TARGET_CHAR_BIT);
- result = read_address (buf,
- buf + TARGET_ADDR_BIT / TARGET_CHAR_BIT,
- &bytes_read);
+ gdb_byte *buf = alloca (ctx->addr_size);
+ (ctx->read_mem) (ctx->baton, buf, result, ctx->addr_size);
+ result = dwarf2_read_address (ctx->gdbarch,
+ buf, buf + ctx->addr_size,
+ ctx->addr_size);
}
break;
case DW_OP_deref_size:
{
- char *buf = alloca (TARGET_ADDR_BIT / TARGET_CHAR_BIT);
- int bytes_read;
-
- (ctx->read_mem) (ctx->baton, buf, result, *op_ptr++);
- result = read_address (buf,
- buf + TARGET_ADDR_BIT / TARGET_CHAR_BIT,
- &bytes_read);
+ int addr_size = *op_ptr++;
+ gdb_byte *buf = alloca (addr_size);
+ (ctx->read_mem) (ctx->baton, buf, result, addr_size);
+ result = dwarf2_read_address (ctx->gdbarch,
+ buf, buf + addr_size,
+ addr_size);
}
break;
second = dwarf_expr_fetch (ctx, 0);
dwarf_expr_pop (ctx);
- first = dwarf_expr_fetch (ctx, 1);
+ first = dwarf_expr_fetch (ctx, 0);
dwarf_expr_pop (ctx);
- val1 = value_from_longest (unsigned_address_type (), first);
- val2 = value_from_longest (unsigned_address_type (), second);
+ val1 = value_from_longest
+ (unsigned_address_type (ctx->addr_size), first);
+ val2 = value_from_longest
+ (unsigned_address_type (ctx->addr_size), second);
switch (op)
{
break;
case DW_OP_div:
binop = BINOP_DIV;
+ break;
case DW_OP_minus:
binop = BINOP_SUB;
break;
break;
case DW_OP_shr:
binop = BINOP_RSH;
+ break;
case DW_OP_shra:
binop = BINOP_RSH;
- val1 = value_from_longest (signed_address_type (), first);
+ val1 = value_from_longest
+ (signed_address_type (ctx->addr_size), first);
break;
case DW_OP_xor:
binop = BINOP_BITWISE_XOR;
break;
default:
internal_error (__FILE__, __LINE__,
- "Can't be reached.");
+ _("Can't be reached."));
}
result = value_as_long (value_binop (val1, val2, binop));
}
break;
case DW_OP_GNU_push_tls_address:
+ /* Variable is at a constant offset in the thread-local
+ storage block into the objfile for the current thread and
+ the dynamic linker module containing this expression. Here
+ we return returns the offset from that base. The top of the
+ stack has the offset from the beginning of the thread
+ control block at which the variable is located. Nothing
+ should follow this operator, so the top of stack would be
+ returned. */
result = dwarf_expr_fetch (ctx, 0);
dwarf_expr_pop (ctx);
result = (ctx->get_tls_address) (ctx->baton, result);
case DW_OP_nop:
goto no_push;
+ case DW_OP_piece:
+ {
+ ULONGEST size;
+ CORE_ADDR addr_or_regnum;
+
+ /* Record the piece. */
+ op_ptr = read_uleb128 (op_ptr, op_end, &size);
+ addr_or_regnum = dwarf_expr_fetch (ctx, 0);
+ add_piece (ctx, ctx->in_reg, addr_or_regnum, size);
+
+ /* Pop off the address/regnum, and clear the in_reg flag. */
+ dwarf_expr_pop (ctx);
+ ctx->in_reg = 0;
+ }
+ goto no_push;
+
+ case DW_OP_GNU_uninit:
+ if (op_ptr != op_end)
+ error (_("DWARF-2 expression error: DW_OP_GNU_uninit must always "
+ "be the very last op."));
+
+ ctx->initialized = 0;
+ goto no_push;
+
default:
- error ("Unhandled dwarf expression opcode");
+ error (_("Unhandled dwarf expression opcode 0x%x"), op);
}
/* Most things push a result value. */
dwarf_expr_push (ctx, result);
no_push:;
}
+
+ ctx->recursion_depth--;
+ gdb_assert (ctx->recursion_depth >= 0);
}
projects / deliverable / binutils-gdb.git / blobdiff