/* DWARF 2 Expression Evaluator.
- Copyright (C) 2001, 2002, 2003, 2005, 2007, 2008
+ Copyright (C) 2001, 2002, 2003, 2005, 2007, 2008, 2009, 2010, 2011
Free Software Foundation, Inc.
Contributed by Daniel Berlin (dan@dberlin.org)
#include "gdbtypes.h"
#include "value.h"
#include "gdbcore.h"
-#include "elf/dwarf2.h"
+#include "dwarf2.h"
#include "dwarf2expr.h"
+#include "gdb_assert.h"
/* Local prototypes. */
static void execute_stack_op (struct dwarf_expr_context *,
- gdb_byte *, gdb_byte *);
-static struct type *unsigned_address_type (void);
+ const gdb_byte *, const gdb_byte *);
+
+/* Cookie for gdbarch data. */
+
+static struct gdbarch_data *dwarf_arch_cookie;
+
+/* This holds gdbarch-specific types used by the DWARF expression
+ evaluator. See comments in execute_stack_op. */
+
+struct dwarf_gdbarch_types
+{
+ struct type *dw_types[3];
+};
+
+/* Allocate and fill in dwarf_gdbarch_types for an arch. */
+
+static void *
+dwarf_gdbarch_types_init (struct gdbarch *gdbarch)
+{
+ struct dwarf_gdbarch_types *types
+ = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct dwarf_gdbarch_types);
+
+ /* The types themselves are lazily initialized. */
+
+ return types;
+}
+
+/* Return the type used for DWARF operations where the type is
+ unspecified in the DWARF spec. Only certain sizes are
+ supported. */
+
+static struct type *
+dwarf_expr_address_type (struct dwarf_expr_context *ctx)
+{
+ struct dwarf_gdbarch_types *types = gdbarch_data (ctx->gdbarch,
+ dwarf_arch_cookie);
+ int ndx;
+
+ if (ctx->addr_size == 2)
+ ndx = 0;
+ else if (ctx->addr_size == 4)
+ ndx = 1;
+ else if (ctx->addr_size == 8)
+ ndx = 2;
+ else
+ error (_("Unsupported address size in DWARF expressions: %d bits"),
+ 8 * ctx->addr_size);
+
+ if (types->dw_types[ndx] == NULL)
+ types->dw_types[ndx]
+ = arch_integer_type (ctx->gdbarch,
+ 8 * ctx->addr_size,
+ 0, "<signed DWARF address type>");
+
+ return types->dw_types[ndx];
+}
/* 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;
return retval;
}
xfree (ctx);
}
+/* Helper for make_cleanup_free_dwarf_expr_context. */
+
+static void
+free_dwarf_expr_context_cleanup (void *arg)
+{
+ free_dwarf_expr_context (arg);
+}
+
+/* Return a cleanup that calls free_dwarf_expr_context. */
+
+struct cleanup *
+make_cleanup_free_dwarf_expr_context (struct dwarf_expr_context *ctx)
+{
+ return make_cleanup (free_dwarf_expr_context_cleanup, ctx);
+}
+
/* Expand the memory allocated to CTX's stack to contain at least
NEED more elements than are currently used. */
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)
+static void
+dwarf_expr_push (struct dwarf_expr_context *ctx, struct value *value,
+ int in_stack_memory)
{
+ struct dwarf_stack_value *v;
+
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. */
+/* Push VALUE onto CTX's stack. */
void
+dwarf_expr_push_address (struct dwarf_expr_context *ctx, CORE_ADDR value,
+ int in_stack_memory)
+{
+ dwarf_expr_push (ctx,
+ value_from_ulongest (dwarf_expr_address_type (ctx), value),
+ in_stack_memory);
+}
+
+/* Pop the top item off of CTX's stack. */
+
+static void
dwarf_expr_pop (struct dwarf_expr_context *ctx)
{
if (ctx->stack_len <= 0)
/* Retrieve the N'th item on CTX's stack. */
-CORE_ADDR
+struct value *
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."),
+ 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;
+}
+
+/* Require that TYPE be an integral type; throw an exception if not. */
+
+static void
+dwarf_require_integral (struct type *type)
+{
+ if (TYPE_CODE (type) != TYPE_CODE_INT
+ && TYPE_CODE (type) != TYPE_CODE_CHAR
+ && TYPE_CODE (type) != TYPE_CODE_BOOL)
+ error (_("integral type expected in DWARF expression"));
+}
+
+/* Return the unsigned form of TYPE. TYPE is necessarily an integral
+ type. */
+
+static struct type *
+get_unsigned_type (struct gdbarch *gdbarch, struct type *type)
+{
+ switch (TYPE_LENGTH (type))
+ {
+ case 1:
+ return builtin_type (gdbarch)->builtin_uint8;
+ 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:
+ error (_("no unsigned variant found for type, while evaluating "
+ "DWARF expression"));
+ }
+}
+
+/* Return the signed form of TYPE. TYPE is necessarily an integral
+ type. */
+static struct type *
+get_signed_type (struct gdbarch *gdbarch, struct type *type)
+{
+ switch (TYPE_LENGTH (type))
+ {
+ case 1:
+ return builtin_type (gdbarch)->builtin_int8;
+ 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:
+ error (_("no signed variant found for type, while evaluating "
+ "DWARF expression"));
+ }
+}
+
+/* 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)
+{
+ struct value *result_val = dwarf_expr_fetch (ctx, n);
+ enum bfd_endian byte_order = gdbarch_byte_order (ctx->gdbarch);
+ ULONGEST result;
+
+ dwarf_require_integral (value_type (result_val));
+ result = extract_unsigned_integer (value_contents (result_val),
+ TYPE_LENGTH (value_type (result_val)),
+ byte_order);
+
+ /* 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))
+ {
+ gdb_byte *buf = alloca (ctx->addr_size);
+ struct type *int_type = get_unsigned_type (ctx->gdbarch,
+ value_type (result_val));
+
+ 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,
- int in_reg, CORE_ADDR value, 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->in_reg = in_reg;
- p->value = value;
+ 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 if (p->location == DWARF_VALUE_IMPLICIT_POINTER)
+ {
+ p->v.ptr.die = ctx->len;
+ p->v.ptr.offset = value_as_long (dwarf_expr_fetch (ctx, 0));
+ }
+ else if (p->location == DWARF_VALUE_REGISTER)
+ p->v.regno = value_as_long (dwarf_expr_fetch (ctx, 0));
+ else
+ {
+ 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;
+
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. */
-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;
error (_("read_uleb128: Corrupted DWARF expression."));
byte = *buf++;
- result |= (byte & 0x7f) << shift;
+ result |= ((ULONGEST) (byte & 0x7f)) << shift;
if ((byte & 0x80) == 0)
break;
shift += 7;
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;
error (_("read_sleb128: Corrupted DWARF expression."));
byte = *buf++;
- result |= (byte & 0x7f) << shift;
+ result |= ((ULONGEST) (byte & 0x7f)) << shift;
shift += 7;
if ((byte & 0x80) == 0)
break;
}
if (shift < (sizeof (*r) * 8) && (byte & 0x40) != 0)
- result |= -(1 << shift);
+ result |= -(((LONGEST) 1) << shift);
*r = result;
return buf;
}
+\f
-/* 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. */
+/* Check that the current operator is either at the end of an
+ expression, or that it is followed by a composition operator. */
-CORE_ADDR
-dwarf2_read_address (gdb_byte *buf, gdb_byte *buf_end, int *bytes_read)
+void
+dwarf_expr_require_composition (const gdb_byte *op_ptr, const gdb_byte *op_end,
+ const char *op_name)
{
- CORE_ADDR result;
-
- if (buf_end - buf < gdbarch_addr_bit (current_gdbarch) / TARGET_CHAR_BIT)
- error (_("dwarf2_read_address: Corrupted DWARF expression."));
-
- *bytes_read = gdbarch_addr_bit (current_gdbarch) / TARGET_CHAR_BIT;
-
- /* 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. Turning the unsigned integer into a value and then
- decomposing that value as an address will cause
- gdbarch_integer_to_address() to be invoked for those
- architectures which require it. Thus, using value_as_address()
- will produce the correct result for both types of architectures.
-
- One concern regarding the use of values for this purpose is
- efficiency. Obviously, these extra calls will take more time to
- execute and creating a value takes more space, space which will
- have to be garbage collected at a later time. If constructing
- and then decomposing a value for this purpose proves to be too
- inefficient, then gdbarch_integer_to_address() can be called
- directly.
-
- 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. */
-
- result = value_as_address (value_from_longest
- (unsigned_address_type (),
- extract_unsigned_integer
- (buf,
- gdbarch_addr_bit (current_gdbarch)
- / TARGET_CHAR_BIT)));
-
- return result;
+ /* 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
+ checked at the other place that this function is called. */
+ if (op_ptr != op_end && *op_ptr != DW_OP_piece && *op_ptr != DW_OP_bit_piece)
+ error (_("DWARF-2 expression error: `%s' operations must be "
+ "used either alone or in conjunction with DW_OP_piece "
+ "or DW_OP_bit_piece."),
+ op_name);
}
-/* Return the type of an address, for unsigned arithmetic. */
+/* Return true iff the types T1 and T2 are "the same". This only does
+ checks that might reasonably be needed to compare DWARF base
+ types. */
-static struct type *
-unsigned_address_type (void)
+static int
+base_types_equal_p (struct type *t1, struct type *t2)
{
- switch (gdbarch_addr_bit (current_gdbarch) / TARGET_CHAR_BIT)
- {
- case 2:
- return builtin_type_uint16;
- case 4:
- return builtin_type_uint32;
- case 8:
- return builtin_type_uint64;
- default:
- internal_error (__FILE__, __LINE__,
- _("Unsupported address size.\n"));
- }
+ if (TYPE_CODE (t1) != TYPE_CODE (t2))
+ return 0;
+ if (TYPE_UNSIGNED (t1) != TYPE_UNSIGNED (t2))
+ return 0;
+ return TYPE_LENGTH (t1) == TYPE_LENGTH (t2);
}
-/* Return the type of an address, for signed arithmetic. */
+/* A convenience function to call get_base_type on CTX and return the
+ result. DIE is the DIE whose type we need. SIZE is non-zero if
+ this function should verify that the resulting type has the correct
+ size. */
static struct type *
-signed_address_type (void)
+dwarf_get_base_type (struct dwarf_expr_context *ctx, ULONGEST die, int size)
{
- switch (gdbarch_addr_bit (current_gdbarch) / TARGET_CHAR_BIT)
+ struct type *result;
+
+ if (ctx->funcs->get_base_type)
{
- case 2:
- return builtin_type_int16;
- case 4:
- return builtin_type_int32;
- case 8:
- return builtin_type_int64;
- default:
- internal_error (__FILE__, __LINE__,
- _("Unsupported address size.\n"));
+ result = ctx->funcs->get_base_type (ctx, die);
+ if (result == NULL)
+ error (_("Could not find type for DW_OP_GNU_const_type"));
+ if (size != 0 && TYPE_LENGTH (result) != size)
+ error (_("DW_OP_GNU_const_type has different sizes for type and data"));
}
+ else
+ /* Anything will do. */
+ result = builtin_type (ctx->gdbarch)->builtin_int;
+
+ return result;
}
-\f
+
/* The engine for the expression evaluator. Using the context in CTX,
evaluate the expression between OP_PTR and OP_END. */
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)
{
- ctx->in_reg = 0;
+ enum bfd_endian byte_order = gdbarch_byte_order (ctx->gdbarch);
+ /* Old-style "untyped" DWARF values need special treatment in a
+ couple of places, specifically DW_OP_mod and DW_OP_shr. We need
+ a special type for these values so we can distinguish them from
+ values that have an explicit type, because explicitly-typed
+ values do not need special treatment. This special type must be
+ different (in the `==' sense) from any base type coming from the
+ CU. */
+ struct type *address_type = dwarf_expr_address_type (ctx);
+
+ ctx->location = DWARF_VALUE_MEMORY;
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;
+ 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;
- int bytes_read;
+ struct value *result_val = NULL;
+
+ /* The DWARF expression might have a bug causing an infinite
+ loop. In that case, quitting is the only way out. */
+ QUIT;
switch (op)
{
case DW_OP_lit30:
case DW_OP_lit31:
result = op - DW_OP_lit0;
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_addr:
- result = dwarf2_read_address (op_ptr, op_end, &bytes_read);
- op_ptr += bytes_read;
+ 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;
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_const1u:
- result = extract_unsigned_integer (op_ptr, 1);
+ result = extract_unsigned_integer (op_ptr, 1, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 1;
break;
case DW_OP_const1s:
- result = extract_signed_integer (op_ptr, 1);
+ result = extract_signed_integer (op_ptr, 1, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 1;
break;
case DW_OP_const2u:
- result = extract_unsigned_integer (op_ptr, 2);
+ result = extract_unsigned_integer (op_ptr, 2, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 2;
break;
case DW_OP_const2s:
- result = extract_signed_integer (op_ptr, 2);
+ result = extract_signed_integer (op_ptr, 2, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 2;
break;
case DW_OP_const4u:
- result = extract_unsigned_integer (op_ptr, 4);
+ result = extract_unsigned_integer (op_ptr, 4, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 4;
break;
case DW_OP_const4s:
- result = extract_signed_integer (op_ptr, 4);
+ result = extract_signed_integer (op_ptr, 4, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 4;
break;
case DW_OP_const8u:
- result = extract_unsigned_integer (op_ptr, 8);
+ result = extract_unsigned_integer (op_ptr, 8, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 8;
break;
case DW_OP_const8s:
- result = extract_signed_integer (op_ptr, 8);
+ result = extract_signed_integer (op_ptr, 8, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 8;
break;
case DW_OP_constu:
op_ptr = read_uleb128 (op_ptr, op_end, &uoffset);
result = uoffset;
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_consts:
op_ptr = read_sleb128 (op_ptr, op_end, &offset);
result = offset;
+ result_val = value_from_ulongest (address_type, result);
break;
/* The DW_OP_reg operations are required to occur alone in
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 conjunction with DW_OP_piece "
+ "or DW_OP_bit_piece."));
result = op - DW_OP_reg0;
- ctx->in_reg = 1;
-
+ result_val = value_from_ulongest (address_type, result);
+ ctx->location = DWARF_VALUE_REGISTER;
break;
case DW_OP_regx:
op_ptr = read_uleb128 (op_ptr, op_end, ®);
- 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."));
+ dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_regx");
result = reg;
- ctx->in_reg = 1;
+ result_val = value_from_ulongest (address_type, result);
+ ctx->location = DWARF_VALUE_REGISTER;
+ break;
+
+ 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->len = len;
+ ctx->data = op_ptr;
+ ctx->location = DWARF_VALUE_LITERAL;
+ op_ptr += len;
+ 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;
+ dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_stack_value");
+ goto no_push;
+
+ case DW_OP_GNU_implicit_pointer:
+ {
+ ULONGEST die;
+ LONGEST len;
+
+ /* The referred-to DIE. */
+ ctx->len = extract_unsigned_integer (op_ptr, ctx->addr_size,
+ byte_order);
+ op_ptr += ctx->addr_size;
+
+ /* The byte offset into the data. */
+ op_ptr = read_sleb128 (op_ptr, op_end, &len);
+ result = (ULONGEST) len;
+ result_val = value_from_ulongest (address_type, result);
+
+ ctx->location = DWARF_VALUE_IMPLICIT_POINTER;
+ dwarf_expr_require_composition (op_ptr, op_end,
+ "DW_OP_GNU_implicit_pointer");
+ }
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);
+ result = (ctx->funcs->read_reg) (ctx->baton, op - DW_OP_breg0);
result += offset;
+ result_val = value_from_ulongest (address_type, result);
}
break;
case DW_OP_bregx:
{
op_ptr = read_uleb128 (op_ptr, op_end, ®);
op_ptr = read_sleb128 (op_ptr, op_end, &offset);
- result = (ctx->read_reg) (ctx->baton, reg);
+ result = (ctx->funcs->read_reg) (ctx->baton, reg);
result += offset;
+ result_val = value_from_ulongest (address_type, result);
}
break;
case DW_OP_fbreg:
{
- gdb_byte *datastart;
+ const gdb_byte *datastart;
size_t datalen;
unsigned int before_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);
+ (ctx->funcs->get_frame_base) (ctx->baton, &datastart, &datalen);
dwarf_expr_eval (ctx, datastart, datalen);
- result = dwarf_expr_fetch (ctx, 0);
- if (ctx->in_reg)
- result = (ctx->read_reg) (ctx->baton, result);
+ if (ctx->location == DWARF_VALUE_MEMORY)
+ result = dwarf_expr_fetch_address (ctx, 0);
+ else if (ctx->location == DWARF_VALUE_REGISTER)
+ result = (ctx->funcs->read_reg) (ctx->baton,
+ value_as_long (dwarf_expr_fetch (ctx, 0)));
+ else
+ error (_("Not implemented: computing frame "
+ "base using explicit value operator"));
result = result + offset;
+ result_val = value_from_ulongest (address_type, result);
+ in_stack_memory = 1;
ctx->stack_len = before_stack_len;
- ctx->in_reg = 0;
+ ctx->location = DWARF_VALUE_MEMORY;
}
break;
+
case DW_OP_dup:
- result = dwarf_expr_fetch (ctx, 0);
+ result_val = 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);
+ result_val = dwarf_expr_fetch (ctx, offset);
+ in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, offset);
break;
+
+ case DW_OP_swap:
+ {
+ struct dwarf_stack_value 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);
+ result_val = 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."),
+ 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:
case DW_OP_deref_size:
+ case DW_OP_GNU_deref_type:
+ {
+ 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);
+ struct type *type;
+
+ dwarf_expr_pop (ctx);
+
+ if (op == DW_OP_GNU_deref_type)
+ {
+ ULONGEST type_die;
+
+ op_ptr = read_uleb128 (op_ptr, op_end, &type_die);
+ type = dwarf_get_base_type (ctx, type_die, 0);
+ }
+ else
+ type = address_type;
+
+ (ctx->funcs->read_mem) (ctx->baton, buf, addr, addr_size);
+
+ /* If the size of the object read from memory is different
+ from the type length, we need to zero-extend it. */
+ if (TYPE_LENGTH (type) != addr_size)
+ {
+ ULONGEST result =
+ extract_unsigned_integer (buf, addr_size, byte_order);
+
+ buf = alloca (TYPE_LENGTH (type));
+ store_unsigned_integer (buf, TYPE_LENGTH (type),
+ byte_order, result);
+ }
+
+ result_val = value_from_contents_and_address (type, buf, addr);
+ break;
+ }
+
case DW_OP_abs:
case DW_OP_neg:
case DW_OP_not:
case DW_OP_plus_uconst:
- /* Unary operations. */
- result = dwarf_expr_fetch (ctx, 0);
- dwarf_expr_pop (ctx);
-
- switch (op)
- {
- case DW_OP_deref:
- {
- gdb_byte *buf = alloca (gdbarch_addr_bit (current_gdbarch)
- / TARGET_CHAR_BIT);
- int bytes_read;
-
- (ctx->read_mem) (ctx->baton, buf, result,
- gdbarch_addr_bit (current_gdbarch)
- / TARGET_CHAR_BIT);
- result = dwarf2_read_address (buf,
- buf + (gdbarch_addr_bit
- (current_gdbarch)
- / TARGET_CHAR_BIT),
- &bytes_read);
- }
- break;
+ {
+ /* Unary operations. */
+ result_val = dwarf_expr_fetch (ctx, 0);
+ dwarf_expr_pop (ctx);
- case DW_OP_deref_size:
+ switch (op)
{
- gdb_byte *buf
- = alloca (gdbarch_addr_bit (current_gdbarch)
- / TARGET_CHAR_BIT);
- int bytes_read;
-
- (ctx->read_mem) (ctx->baton, buf, result, *op_ptr++);
- result = dwarf2_read_address (buf,
- buf + (gdbarch_addr_bit
- (current_gdbarch)
- / TARGET_CHAR_BIT),
- &bytes_read);
+ case DW_OP_abs:
+ if (value_less (result_val,
+ value_zero (value_type (result_val), not_lval)))
+ result_val = value_neg (result_val);
+ break;
+ case DW_OP_neg:
+ result_val = value_neg (result_val);
+ break;
+ case DW_OP_not:
+ dwarf_require_integral (value_type (result_val));
+ result_val = value_complement (result_val);
+ break;
+ case DW_OP_plus_uconst:
+ dwarf_require_integral (value_type (result_val));
+ result = value_as_long (result_val);
+ op_ptr = read_uleb128 (op_ptr, op_end, ®);
+ result += reg;
+ result_val = value_from_ulongest (address_type, result);
+ break;
}
- break;
-
- case DW_OP_abs:
- if ((signed int) result < 0)
- result = -result;
- break;
- case DW_OP_neg:
- result = -result;
- break;
- case DW_OP_not:
- result = ~result;
- break;
- case DW_OP_plus_uconst:
- op_ptr = read_uleb128 (op_ptr, op_end, ®);
- result += reg;
- break;
- }
+ }
break;
case DW_OP_and:
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;
+ /* Binary operations. */
+ struct value *first, *second;
second = dwarf_expr_fetch (ctx, 0);
dwarf_expr_pop (ctx);
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);
+ if (! base_types_equal_p (value_type (first), value_type (second)))
+ error (_("Incompatible types on DWARF stack"));
switch (op)
{
case DW_OP_and:
- binop = BINOP_BITWISE_AND;
+ dwarf_require_integral (value_type (first));
+ dwarf_require_integral (value_type (second));
+ result_val = value_binop (first, second, BINOP_BITWISE_AND);
break;
case DW_OP_div:
- binop = BINOP_DIV;
+ result_val = value_binop (first, second, BINOP_DIV);
break;
case DW_OP_minus:
- binop = BINOP_SUB;
+ result_val = value_binop (first, second, BINOP_SUB);
break;
case DW_OP_mod:
- binop = BINOP_MOD;
+ {
+ int cast_back = 0;
+ struct type *orig_type = value_type (first);
+
+ /* We have to special-case "old-style" untyped values
+ -- these must have mod computed using unsigned
+ math. */
+ if (orig_type == address_type)
+ {
+ struct type *utype
+ = get_unsigned_type (ctx->gdbarch, orig_type);
+
+ cast_back = 1;
+ first = value_cast (utype, first);
+ second = value_cast (utype, second);
+ }
+ /* Note that value_binop doesn't handle float or
+ decimal float here. This seems unimportant. */
+ result_val = value_binop (first, second, BINOP_MOD);
+ if (cast_back)
+ result_val = value_cast (orig_type, result_val);
+ }
break;
case DW_OP_mul:
- binop = BINOP_MUL;
+ result_val = value_binop (first, second, BINOP_MUL);
break;
case DW_OP_or:
- binop = BINOP_BITWISE_IOR;
+ dwarf_require_integral (value_type (first));
+ dwarf_require_integral (value_type (second));
+ result_val = value_binop (first, second, BINOP_BITWISE_IOR);
break;
case DW_OP_plus:
- binop = BINOP_ADD;
+ result_val = value_binop (first, second, BINOP_ADD);
break;
case DW_OP_shl:
- binop = BINOP_LSH;
+ dwarf_require_integral (value_type (first));
+ dwarf_require_integral (value_type (second));
+ result_val = value_binop (first, second, BINOP_LSH);
break;
case DW_OP_shr:
- binop = BINOP_RSH;
+ dwarf_require_integral (value_type (first));
+ dwarf_require_integral (value_type (second));
+ if (!TYPE_UNSIGNED (value_type (first)))
+ {
+ struct type *utype
+ = get_unsigned_type (ctx->gdbarch, value_type (first));
+
+ first = value_cast (utype, first);
+ }
+
+ result_val = value_binop (first, second, BINOP_RSH);
+ /* Make sure we wind up with the same type we started
+ with. */
+ if (value_type (result_val) != value_type (second))
+ result_val = value_cast (value_type (second), result_val);
break;
case DW_OP_shra:
- binop = BINOP_RSH;
- val1 = value_from_longest (signed_address_type (), first);
+ dwarf_require_integral (value_type (first));
+ dwarf_require_integral (value_type (second));
+ if (TYPE_UNSIGNED (value_type (first)))
+ {
+ struct type *stype
+ = get_signed_type (ctx->gdbarch, value_type (first));
+
+ first = value_cast (stype, first);
+ }
+
+ result_val = value_binop (first, second, BINOP_RSH);
+ /* Make sure we wind up with the same type we started
+ with. */
+ if (value_type (result_val) != value_type (second))
+ result_val = value_cast (value_type (second), result_val);
break;
case DW_OP_xor:
- binop = BINOP_BITWISE_XOR;
+ dwarf_require_integral (value_type (first));
+ dwarf_require_integral (value_type (second));
+ result_val = value_binop (first, second, BINOP_BITWISE_XOR);
break;
case DW_OP_le:
- binop = BINOP_LEQ;
+ /* A <= B is !(B < A). */
+ result = ! value_less (second, first);
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_ge:
- binop = BINOP_GEQ;
+ /* A >= B is !(A < B). */
+ result = ! value_less (first, second);
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_eq:
- binop = BINOP_EQUAL;
+ result = value_equal (first, second);
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_lt:
- binop = BINOP_LESS;
+ result = value_less (first, second);
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_gt:
- binop = BINOP_GTR;
+ /* A > B is B < A. */
+ result = value_less (second, first);
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_ne:
- binop = BINOP_NOTEQUAL;
+ result = ! value_equal (first, second);
+ result_val = value_from_ulongest (address_type, result);
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->funcs->get_frame_cfa) (ctx->baton);
+ result_val = value_from_ulongest (address_type, result);
+ in_stack_memory = 1;
+ 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
+ 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);
+ result = value_as_long (dwarf_expr_fetch (ctx, 0));
dwarf_expr_pop (ctx);
- result = (ctx->get_tls_address) (ctx->baton, result);
+ result = (ctx->funcs->get_tls_address) (ctx->baton, result);
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_skip:
- offset = extract_signed_integer (op_ptr, 2);
+ offset = extract_signed_integer (op_ptr, 2, byte_order);
op_ptr += 2;
op_ptr += offset;
goto no_push;
case DW_OP_bra:
- offset = extract_signed_integer (op_ptr, 2);
- op_ptr += 2;
- if (dwarf_expr_fetch (ctx, 0) != 0)
- op_ptr += offset;
- dwarf_expr_pop (ctx);
+ {
+ struct value *val;
+
+ offset = extract_signed_integer (op_ptr, 2, byte_order);
+ op_ptr += 2;
+ val = dwarf_expr_fetch (ctx, 0);
+ dwarf_require_integral (value_type (val));
+ if (value_as_long (val) != 0)
+ op_ptr += offset;
+ dwarf_expr_pop (ctx);
+ }
goto no_push;
case DW_OP_nop:
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;
+ add_piece (ctx, 8 * size, 0);
+
+ /* 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_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_unint must always "
+ error (_("DWARF-2 expression error: DW_OP_GNU_uninit must always "
"be the very last op."));
ctx->initialized = 0;
goto no_push;
+ case DW_OP_call2:
+ result = extract_unsigned_integer (op_ptr, 2, byte_order);
+ op_ptr += 2;
+ ctx->funcs->dwarf_call (ctx, result);
+ goto no_push;
+
+ case DW_OP_call4:
+ result = extract_unsigned_integer (op_ptr, 4, byte_order);
+ op_ptr += 4;
+ ctx->funcs->dwarf_call (ctx, result);
+ goto no_push;
+
+ case DW_OP_GNU_entry_value:
+ /* This operation is not yet supported by GDB. */
+ ctx->location = DWARF_VALUE_OPTIMIZED_OUT;
+ ctx->stack_len = 0;
+ ctx->num_pieces = 0;
+ goto abort_expression;
+
+ case DW_OP_GNU_const_type:
+ {
+ ULONGEST type_die;
+ int n;
+ const gdb_byte *data;
+ struct type *type;
+
+ op_ptr = read_uleb128 (op_ptr, op_end, &type_die);
+ n = *op_ptr++;
+ data = op_ptr;
+ op_ptr += n;
+
+ type = dwarf_get_base_type (ctx, type_die, n);
+ result_val = value_from_contents (type, data);
+ }
+ break;
+
+ case DW_OP_GNU_regval_type:
+ {
+ ULONGEST type_die;
+ struct type *type;
+
+ op_ptr = read_uleb128 (op_ptr, op_end, ®);
+ op_ptr = read_uleb128 (op_ptr, op_end, &type_die);
+
+ type = dwarf_get_base_type (ctx, type_die, 0);
+ result = (ctx->funcs->read_reg) (ctx->baton, reg);
+ result_val = value_from_ulongest (address_type, result);
+ result_val = value_from_contents (type,
+ value_contents_all (result_val));
+ }
+ break;
+
+ case DW_OP_GNU_convert:
+ case DW_OP_GNU_reinterpret:
+ {
+ ULONGEST type_die;
+ struct type *type;
+
+ op_ptr = read_uleb128 (op_ptr, op_end, &type_die);
+
+ if (type_die == 0)
+ type = address_type;
+ else
+ type = dwarf_get_base_type (ctx, type_die, 0);
+
+ result_val = dwarf_expr_fetch (ctx, 0);
+ dwarf_expr_pop (ctx);
+
+ if (op == DW_OP_GNU_convert)
+ result_val = value_cast (type, result_val);
+ else if (type == value_type (result_val))
+ {
+ /* Nothing. */
+ }
+ else if (TYPE_LENGTH (type)
+ != TYPE_LENGTH (value_type (result_val)))
+ error (_("DW_OP_GNU_reinterpret has wrong size"));
+ else
+ result_val
+ = value_from_contents (type,
+ value_contents_all (result_val));
+ }
+ break;
+
default:
error (_("Unhandled dwarf expression opcode 0x%x"), op);
}
/* Most things push a result value. */
- dwarf_expr_push (ctx, result);
- no_push:;
+ gdb_assert (result_val != NULL);
+ dwarf_expr_push (ctx, result_val, in_stack_memory);
+ no_push:
+ ;
}
+
+ /* To simplify our main caller, if the result is an implicit
+ pointer, then make a pieced value. This is ok because we can't
+ have implicit pointers in contexts where pieces are invalid. */
+ if (ctx->location == DWARF_VALUE_IMPLICIT_POINTER)
+ add_piece (ctx, 8 * ctx->addr_size, 0);
+
+abort_expression:
+ ctx->recursion_depth--;
+ gdb_assert (ctx->recursion_depth >= 0);
+}
+
+/* Stub dwarf_expr_context_funcs.read_reg implementation. */
+
+CORE_ADDR
+ctx_no_read_reg (void *baton, int regnum)
+{
+ error (_("Registers access is invalid in this context"));
+}
+
+/* Stub dwarf_expr_context_funcs.get_frame_base implementation. */
+
+void
+ctx_no_get_frame_base (void *baton, const gdb_byte **start, size_t *length)
+{
+ error (_("%s is invalid in this context"), "DW_OP_fbreg");
+}
+
+/* Stub dwarf_expr_context_funcs.get_frame_cfa implementation. */
+
+CORE_ADDR
+ctx_no_get_frame_cfa (void *baton)
+{
+ error (_("%s is invalid in this context"), "DW_OP_call_frame_cfa");
+}
+
+/* Stub dwarf_expr_context_funcs.get_frame_pc implementation. */
+
+CORE_ADDR
+ctx_no_get_frame_pc (void *baton)
+{
+ error (_("%s is invalid in this context"), "DW_OP_GNU_implicit_pointer");
+}
+
+/* Stub dwarf_expr_context_funcs.get_tls_address implementation. */
+
+CORE_ADDR
+ctx_no_get_tls_address (void *baton, CORE_ADDR offset)
+{
+ error (_("%s is invalid in this context"), "DW_OP_GNU_push_tls_address");
+}
+
+/* Stub dwarf_expr_context_funcs.dwarf_call implementation. */
+
+void
+ctx_no_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset)
+{
+ error (_("%s is invalid in this context"), "DW_OP_call*");
+}
+
+/* Stub dwarf_expr_context_funcs.get_base_type implementation. */
+
+struct type *
+ctx_no_get_base_type (struct dwarf_expr_context *ctx, size_t die)
+{
+ error (_("Support for typed DWARF is not supported in this context"));
+}
+
+void
+_initialize_dwarf2expr (void)
+{
+ dwarf_arch_cookie
+ = gdbarch_data_register_post_init (dwarf_gdbarch_types_init);
}