/* DWARF 2 Expression Evaluator.
- Copyright (C) 2001, 2002, 2003, 2005, 2007, 2008, 2009
+ Copyright (C) 2001, 2002, 2003, 2005, 2007, 2008, 2009, 2010
Free Software Foundation, Inc.
Contributed by Daniel Berlin (dan@dberlin.org)
/* Local prototypes. */
static void execute_stack_op (struct dwarf_expr_context *,
- gdb_byte *, gdb_byte *);
-static struct type *unsigned_address_type (struct gdbarch *, int);
+ const gdb_byte *, const gdb_byte *);
/* Create a new context for the expression evaluator. */
new_dwarf_expr_context (void)
{
struct dwarf_expr_context *retval;
+
retval = xcalloc (1, sizeof (struct dwarf_expr_context));
retval->stack_len = 0;
retval->stack_allocated = 10;
- retval->stack = xmalloc (retval->stack_allocated * sizeof (CORE_ADDR));
+ retval->stack = xmalloc (retval->stack_allocated
+ * sizeof (struct dwarf_stack_value));
retval->num_pieces = 0;
retval->pieces = 0;
retval->max_recursion_depth = 0x100;
if (ctx->stack_len + need > ctx->stack_allocated)
{
size_t newlen = ctx->stack_len + need + 10;
+
ctx->stack = xrealloc (ctx->stack,
- newlen * sizeof (CORE_ADDR));
+ newlen * sizeof (struct dwarf_stack_value));
ctx->stack_allocated = newlen;
}
}
/* Push VALUE onto CTX's stack. */
void
-dwarf_expr_push (struct dwarf_expr_context *ctx, CORE_ADDR value)
+dwarf_expr_push (struct dwarf_expr_context *ctx, ULONGEST value,
+ int in_stack_memory)
{
+ struct dwarf_stack_value *v;
+
+ /* We keep all stack elements within the range defined by the
+ DWARF address size. */
+ if (ctx->addr_size < sizeof (ULONGEST))
+ value &= ((ULONGEST) 1 << (ctx->addr_size * HOST_CHAR_BIT)) - 1;
+
dwarf_expr_grow_stack (ctx, 1);
- ctx->stack[ctx->stack_len++] = value;
+ v = &ctx->stack[ctx->stack_len++];
+ v->value = value;
+ v->in_stack_memory = in_stack_memory;
}
/* Pop the top item off of CTX's stack. */
/* Retrieve the N'th item on CTX's stack. */
-CORE_ADDR
+ULONGEST
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, ctx->stack_len);
- return ctx->stack[ctx->stack_len - (1 + n)];
+ return ctx->stack[ctx->stack_len - (1 + n)].value;
+
+}
+
+/* Retrieve the N'th item on CTX's stack, converted to an address. */
+
+CORE_ADDR
+dwarf_expr_fetch_address (struct dwarf_expr_context *ctx, int n)
+{
+ ULONGEST result = dwarf_expr_fetch (ctx, n);
+
+ /* 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. */
+ if (gdbarch_integer_to_address_p (ctx->gdbarch))
+ {
+ enum bfd_endian byte_order = gdbarch_byte_order (ctx->gdbarch);
+ gdb_byte *buf = alloca (ctx->addr_size);
+ struct type *int_type;
+
+ switch (ctx->addr_size)
+ {
+ case 2:
+ int_type = builtin_type (ctx->gdbarch)->builtin_uint16;
+ break;
+ case 4:
+ int_type = builtin_type (ctx->gdbarch)->builtin_uint32;
+ break;
+ case 8:
+ int_type = builtin_type (ctx->gdbarch)->builtin_uint64;
+ break;
+ default:
+ internal_error (__FILE__, __LINE__,
+ _("Unsupported address size.\n"));
+ }
+
+ store_unsigned_integer (buf, ctx->addr_size, byte_order, result);
+ return gdbarch_integer_to_address (ctx->gdbarch, int_type, buf);
+ }
+
+ return (CORE_ADDR) result;
+}
+
+/* Retrieve the in_stack_memory flag of the N'th item on CTX's stack. */
+
+int
+dwarf_expr_fetch_in_stack_memory (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, ctx->stack_len);
+ return ctx->stack[ctx->stack_len - (1 + n)].in_stack_memory;
}
+/* Return true if the expression stack is empty. */
+
+static int
+dwarf_expr_stack_empty_p (struct dwarf_expr_context *ctx)
+{
+ return ctx->stack_len == 0;
+}
+
/* Add a new piece to CTX's piece list. */
static void
-add_piece (struct dwarf_expr_context *ctx, ULONGEST size)
+add_piece (struct dwarf_expr_context *ctx, ULONGEST size, ULONGEST offset)
{
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));
+ ctx->pieces = xrealloc (ctx->pieces,
+ (ctx->num_pieces
+ * sizeof (struct dwarf_expr_piece)));
p = &ctx->pieces[ctx->num_pieces - 1];
p->location = ctx->location;
p->size = size;
+ p->offset = offset;
+
if (p->location == DWARF_VALUE_LITERAL)
{
p->v.literal.data = ctx->data;
p->v.literal.length = ctx->len;
}
+ else if (dwarf_expr_stack_empty_p (ctx))
+ {
+ p->location = DWARF_VALUE_OPTIMIZED_OUT;
+ /* Also reset the context's location, for our callers. This is
+ a somewhat strange approach, but this lets us avoid setting
+ the location to DWARF_VALUE_MEMORY in all the individual
+ cases in the evaluator. */
+ ctx->location = DWARF_VALUE_OPTIMIZED_OUT;
+ }
+ else if (p->location == DWARF_VALUE_MEMORY)
+ {
+ p->v.mem.addr = dwarf_expr_fetch_address (ctx, 0);
+ p->v.mem.in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 0);
+ }
else
- p->v.value = dwarf_expr_fetch (ctx, 0);
+ {
+ p->v.value = dwarf_expr_fetch (ctx, 0);
+ }
}
/* Evaluate the expression at ADDR (LEN bytes long) using the context
CTX. */
void
-dwarf_expr_eval (struct dwarf_expr_context *ctx, gdb_byte *addr, size_t len)
+dwarf_expr_eval (struct dwarf_expr_context *ctx, const gdb_byte *addr,
+ size_t len)
{
int old_recursion_depth = ctx->recursion_depth;
by R, and return the new value of BUF. Verify that it doesn't extend
past BUF_END. */
-gdb_byte *
-read_uleb128 (gdb_byte *buf, gdb_byte *buf_end, ULONGEST * r)
+const gdb_byte *
+read_uleb128 (const gdb_byte *buf, const gdb_byte *buf_end, ULONGEST * r)
{
unsigned shift = 0;
ULONGEST result = 0;
by R, and return the new value of BUF. Verify that it doesn't extend
past BUF_END. */
-gdb_byte *
-read_sleb128 (gdb_byte *buf, gdb_byte *buf_end, LONGEST * r)
+const gdb_byte *
+read_sleb128 (const gdb_byte *buf, const gdb_byte *buf_end, LONGEST * r)
{
unsigned shift = 0;
LONGEST result = 0;
*r = result;
return buf;
}
-
-/* Read an address of size ADDR_SIZE from BUF, and verify that it
- doesn't extend past BUF_END. */
-
-CORE_ADDR
-dwarf2_read_address (struct gdbarch *gdbarch, gdb_byte *buf,
- gdb_byte *buf_end, int addr_size)
-{
- enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
- CORE_ADDR result;
-
- 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.
-
- 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 (gdbarch, addr_size), buf);
-
- return extract_unsigned_integer (buf, addr_size, byte_order);
-}
-
-/* Return the type of an address of size ADDR_SIZE,
- for unsigned arithmetic. */
-
-static struct type *
-unsigned_address_type (struct gdbarch *gdbarch, int addr_size)
-{
- switch (addr_size)
- {
- case 2:
- return builtin_type (gdbarch)->builtin_uint16;
- case 4:
- return builtin_type (gdbarch)->builtin_uint32;
- case 8:
- return builtin_type (gdbarch)->builtin_uint64;
- default:
- internal_error (__FILE__, __LINE__,
- _("Unsupported address size.\n"));
- }
-}
-
-/* Return the type of an address of size ADDR_SIZE,
- for signed arithmetic. */
-
-static struct type *
-signed_address_type (struct gdbarch *gdbarch, int addr_size)
-{
- switch (addr_size)
- {
- case 2:
- return builtin_type (gdbarch)->builtin_int16;
- case 4:
- return builtin_type (gdbarch)->builtin_int32;
- case 8:
- return builtin_type (gdbarch)->builtin_int64;
- default:
- internal_error (__FILE__, __LINE__,
- _("Unsupported address size.\n"));
- }
-}
\f
/* Check that the current operator is either at the end of an
expression, or that it is followed by a composition operator. */
-static void
-require_composition (gdb_byte *op_ptr, gdb_byte *op_end, const char *op_name)
+void
+dwarf_expr_require_composition (const gdb_byte *op_ptr, const gdb_byte *op_end,
+ const char *op_name)
{
/* It seems like DW_OP_GNU_uninit should be handled here. However,
it doesn't seem to make sense for DW_OP_*_value, and it was not
static void
execute_stack_op (struct dwarf_expr_context *ctx,
- gdb_byte *op_ptr, gdb_byte *op_end)
+ const gdb_byte *op_ptr, const gdb_byte *op_end)
{
+#define sign_ext(x) ((LONGEST) (((x) ^ sign_bit) - sign_bit))
+ ULONGEST sign_bit = (ctx->addr_size >= sizeof (ULONGEST) ? 0
+ : ((ULONGEST) 1) << (ctx->addr_size * 8 - 1));
enum bfd_endian byte_order = gdbarch_byte_order (ctx->gdbarch);
+
ctx->location = DWARF_VALUE_MEMORY;
ctx->initialized = 1; /* Default is initialized. */
while (op_ptr < op_end)
{
enum dwarf_location_atom op = *op_ptr++;
- CORE_ADDR result;
+ ULONGEST result;
+ /* Assume the value is not in stack memory.
+ Code that knows otherwise sets this to 1.
+ Some arithmetic on stack addresses can probably be assumed to still
+ be a stack address, but we skip this complication for now.
+ This is just an optimization, so it's always ok to punt
+ and leave this as 0. */
+ int in_stack_memory = 0;
ULONGEST uoffset, reg;
LONGEST offset;
break;
case DW_OP_addr:
- result = dwarf2_read_address (ctx->gdbarch,
- op_ptr, op_end, ctx->addr_size);
+ result = extract_unsigned_integer (op_ptr,
+ ctx->addr_size, byte_order);
op_ptr += ctx->addr_size;
+ /* Some versions of GCC emit DW_OP_addr before
+ DW_OP_GNU_push_tls_address. In this case the value is an
+ index, not an address. We don't support things like
+ branching between the address and the TLS op. */
+ if (op_ptr >= op_end || *op_ptr != DW_OP_GNU_push_tls_address)
+ result += ctx->offset;
break;
case DW_OP_const1u:
case DW_OP_reg31:
if (op_ptr != op_end
&& *op_ptr != DW_OP_piece
+ && *op_ptr != DW_OP_bit_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."));
+ "used either alone or in conjuction with DW_OP_piece "
+ "or DW_OP_bit_piece."));
result = op - DW_OP_reg0;
ctx->location = DWARF_VALUE_REGISTER;
case DW_OP_regx:
op_ptr = read_uleb128 (op_ptr, op_end, ®);
- require_composition (op_ptr, op_end, "DW_OP_regx");
+ dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_regx");
result = reg;
ctx->location = DWARF_VALUE_REGISTER;
case DW_OP_implicit_value:
{
ULONGEST len;
+
op_ptr = read_uleb128 (op_ptr, op_end, &len);
if (op_ptr + len > op_end)
error (_("DW_OP_implicit_value: too few bytes available."));
ctx->data = op_ptr;
ctx->location = DWARF_VALUE_LITERAL;
op_ptr += len;
- require_composition (op_ptr, op_end, "DW_OP_implicit_value");
+ dwarf_expr_require_composition (op_ptr, op_end,
+ "DW_OP_implicit_value");
}
goto no_push;
case DW_OP_stack_value:
ctx->location = DWARF_VALUE_STACK;
- require_composition (op_ptr, op_end, "DW_OP_stack_value");
+ dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_stack_value");
goto no_push;
case DW_OP_breg0:
break;
case DW_OP_fbreg:
{
- gdb_byte *datastart;
+ const gdb_byte *datastart;
size_t datalen;
unsigned int before_stack_len;
specific this_base method. */
(ctx->get_frame_base) (ctx->baton, &datastart, &datalen);
dwarf_expr_eval (ctx, datastart, datalen);
- if (ctx->location == DWARF_VALUE_LITERAL
- || ctx->location == DWARF_VALUE_STACK)
+ if (ctx->location == DWARF_VALUE_MEMORY)
+ result = dwarf_expr_fetch_address (ctx, 0);
+ else if (ctx->location == DWARF_VALUE_REGISTER)
+ result = (ctx->read_reg) (ctx->baton, dwarf_expr_fetch (ctx, 0));
+ else
error (_("Not implemented: computing frame base using explicit value operator"));
- result = dwarf_expr_fetch (ctx, 0);
- if (ctx->location == DWARF_VALUE_REGISTER)
- result = (ctx->read_reg) (ctx->baton, result);
result = result + offset;
+ in_stack_memory = 1;
ctx->stack_len = before_stack_len;
ctx->location = DWARF_VALUE_MEMORY;
}
break;
+
case DW_OP_dup:
result = dwarf_expr_fetch (ctx, 0);
+ in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 0);
break;
case DW_OP_drop:
case DW_OP_pick:
offset = *op_ptr++;
result = dwarf_expr_fetch (ctx, offset);
+ in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, offset);
break;
case DW_OP_swap:
{
- CORE_ADDR t1, t2;
+ struct dwarf_stack_value t1, t2;
if (ctx->stack_len < 2)
error (_("Not enough elements for DW_OP_swap. Need 2, have %d."),
case DW_OP_over:
result = dwarf_expr_fetch (ctx, 1);
+ in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 1);
break;
case DW_OP_rot:
{
- CORE_ADDR t1, t2, t3;
+ struct dwarf_stack_value t1, t2, t3;
if (ctx->stack_len < 3)
error (_("Not enough elements for DW_OP_rot. Need 3, have %d."),
case DW_OP_deref:
case DW_OP_deref_size:
+ {
+ int addr_size = (op == DW_OP_deref ? ctx->addr_size : *op_ptr++);
+ gdb_byte *buf = alloca (addr_size);
+ CORE_ADDR addr = dwarf_expr_fetch_address (ctx, 0);
+ dwarf_expr_pop (ctx);
+
+ (ctx->read_mem) (ctx->baton, buf, addr, addr_size);
+ result = extract_unsigned_integer (buf, addr_size, byte_order);
+ break;
+ }
+
case DW_OP_abs:
case DW_OP_neg:
case DW_OP_not:
switch (op)
{
- case DW_OP_deref:
- {
- 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:
- {
- 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;
-
case DW_OP_abs:
- if ((signed int) result < 0)
+ if (sign_ext (result) < 0)
result = -result;
break;
case DW_OP_neg:
case DW_OP_gt:
case DW_OP_ne:
{
- /* Binary operations. Use the value engine to do computations in
- the right width. */
- CORE_ADDR first, second;
- enum exp_opcode binop;
- struct value *val1, *val2;
- struct type *stype, *utype;
+ /* Binary operations. */
+ ULONGEST first, second;
second = dwarf_expr_fetch (ctx, 0);
dwarf_expr_pop (ctx);
first = dwarf_expr_fetch (ctx, 0);
dwarf_expr_pop (ctx);
- utype = unsigned_address_type (ctx->gdbarch, ctx->addr_size);
- stype = signed_address_type (ctx->gdbarch, ctx->addr_size);
- val1 = value_from_longest (utype, first);
- val2 = value_from_longest (utype, second);
-
switch (op)
{
case DW_OP_and:
- binop = BINOP_BITWISE_AND;
+ result = first & second;
break;
case DW_OP_div:
- binop = BINOP_DIV;
+ if (!second)
+ error (_("Division by zero"));
+ result = sign_ext (first) / sign_ext (second);
break;
case DW_OP_minus:
- binop = BINOP_SUB;
+ result = first - second;
break;
case DW_OP_mod:
- binop = BINOP_MOD;
+ if (!second)
+ error (_("Division by zero"));
+ result = first % second;
break;
case DW_OP_mul:
- binop = BINOP_MUL;
+ result = first * second;
break;
case DW_OP_or:
- binop = BINOP_BITWISE_IOR;
+ result = first | second;
break;
case DW_OP_plus:
- binop = BINOP_ADD;
+ result = first + second;
break;
case DW_OP_shl:
- binop = BINOP_LSH;
+ result = first << second;
break;
case DW_OP_shr:
- binop = BINOP_RSH;
+ result = first >> second;
break;
case DW_OP_shra:
- binop = BINOP_RSH;
- val1 = value_from_longest (stype, first);
+ result = sign_ext (first) >> second;
break;
case DW_OP_xor:
- binop = BINOP_BITWISE_XOR;
+ result = first ^ second;
break;
case DW_OP_le:
- binop = BINOP_LEQ;
+ result = sign_ext (first) <= sign_ext (second);
break;
case DW_OP_ge:
- binop = BINOP_GEQ;
+ result = sign_ext (first) >= sign_ext (second);
break;
case DW_OP_eq:
- binop = BINOP_EQUAL;
+ result = sign_ext (first) == sign_ext (second);
break;
case DW_OP_lt:
- binop = BINOP_LESS;
+ result = sign_ext (first) < sign_ext (second);
break;
case DW_OP_gt:
- binop = BINOP_GTR;
+ result = sign_ext (first) > sign_ext (second);
break;
case DW_OP_ne:
- binop = BINOP_NOTEQUAL;
+ result = sign_ext (first) != sign_ext (second);
break;
default:
internal_error (__FILE__, __LINE__,
_("Can't be reached."));
}
- result = value_as_long (value_binop (val1, val2, binop));
}
break;
case DW_OP_call_frame_cfa:
result = (ctx->get_frame_cfa) (ctx->baton);
+ in_stack_memory = 1;
break;
case DW_OP_GNU_push_tls_address:
case DW_OP_piece:
{
ULONGEST size;
- CORE_ADDR addr_or_regnum;
/* Record the piece. */
op_ptr = read_uleb128 (op_ptr, op_end, &size);
- add_piece (ctx, size);
+ add_piece (ctx, 8 * size, 0);
/* Pop off the address/regnum, and reset the location
type. */
- if (ctx->location != DWARF_VALUE_LITERAL)
+ if (ctx->location != DWARF_VALUE_LITERAL
+ && ctx->location != DWARF_VALUE_OPTIMIZED_OUT)
dwarf_expr_pop (ctx);
ctx->location = DWARF_VALUE_MEMORY;
}
goto no_push;
+ case DW_OP_bit_piece:
+ {
+ ULONGEST size, offset;
+
+ /* Record the piece. */
+ op_ptr = read_uleb128 (op_ptr, op_end, &size);
+ op_ptr = read_uleb128 (op_ptr, op_end, &offset);
+ add_piece (ctx, size, offset);
+
+ /* Pop off the address/regnum, and reset the location
+ type. */
+ if (ctx->location != DWARF_VALUE_LITERAL
+ && ctx->location != DWARF_VALUE_OPTIMIZED_OUT)
+ dwarf_expr_pop (ctx);
+ ctx->location = DWARF_VALUE_MEMORY;
+ }
+ goto no_push;
+
case DW_OP_GNU_uninit:
if (op_ptr != op_end)
error (_("DWARF-2 expression error: DW_OP_GNU_uninit must always "
ctx->initialized = 0;
goto no_push;
+ case DW_OP_call2:
+ result = extract_unsigned_integer (op_ptr, 2, byte_order);
+ op_ptr += 2;
+ ctx->dwarf_call (ctx, result);
+ goto no_push;
+
+ case DW_OP_call4:
+ result = extract_unsigned_integer (op_ptr, 4, byte_order);
+ op_ptr += 4;
+ ctx->dwarf_call (ctx, result);
+ goto no_push;
+
default:
error (_("Unhandled dwarf expression opcode 0x%x"), op);
}
/* Most things push a result value. */
- dwarf_expr_push (ctx, result);
+ dwarf_expr_push (ctx, result, in_stack_memory);
no_push:;
}
ctx->recursion_depth--;
gdb_assert (ctx->recursion_depth >= 0);
+#undef sign_ext
}
projects / deliverable / binutils-gdb.git / blobdiff