/* DWARF 2 Expression Evaluator.
- Copyright (C) 2001, 2002, 2003, 2005, 2007, 2008, 2009, 2010, 2011
- Free Software Foundation, Inc.
+ Copyright (C) 2001-2003, 2005, 2007-2012 Free Software Foundation,
+ Inc.
Contributed by Daniel Berlin (dan@dberlin.org)
}
else if (p->location == DWARF_VALUE_IMPLICIT_POINTER)
{
- p->v.ptr.die = ctx->len;
+ p->v.ptr.die.cu_off = ctx->len;
p->v.ptr.offset = value_as_long (dwarf_expr_fetch (ctx, 0));
}
else if (p->location == DWARF_VALUE_REGISTER)
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. */
+/* Helper to read a uleb128 value or throw an error. */
const gdb_byte *
-read_uleb128 (const gdb_byte *buf, const gdb_byte *buf_end, ULONGEST * r)
+safe_read_uleb128 (const gdb_byte *buf, const gdb_byte *buf_end,
+ uint64_t *r)
{
- unsigned shift = 0;
- ULONGEST result = 0;
- gdb_byte byte;
-
- while (1)
- {
- if (buf >= buf_end)
- error (_("read_uleb128: Corrupted DWARF expression."));
-
- byte = *buf++;
- result |= ((ULONGEST) (byte & 0x7f)) << shift;
- if ((byte & 0x80) == 0)
- break;
- shift += 7;
- }
- *r = result;
+ buf = gdb_read_uleb128 (buf, buf_end, r);
+ if (buf == NULL)
+ error (_("DWARF expression error: ran off end of buffer reading uleb128 value"));
return buf;
}
-/* Decode the signed 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. */
+/* Helper to read a sleb128 value or throw an error. */
const gdb_byte *
-read_sleb128 (const gdb_byte *buf, const gdb_byte *buf_end, LONGEST * r)
+safe_read_sleb128 (const gdb_byte *buf, const gdb_byte *buf_end,
+ int64_t *r)
{
- unsigned shift = 0;
- LONGEST result = 0;
- gdb_byte byte;
-
- while (1)
- {
- if (buf >= buf_end)
- error (_("read_sleb128: Corrupted DWARF expression."));
-
- byte = *buf++;
- result |= ((ULONGEST) (byte & 0x7f)) << shift;
- shift += 7;
- if ((byte & 0x80) == 0)
- break;
- }
- if (shift < (sizeof (*r) * 8) && (byte & 0x40) != 0)
- result |= -(1 << shift);
+ buf = gdb_read_sleb128 (buf, buf_end, r);
+ if (buf == NULL)
+ error (_("DWARF expression error: ran off end of buffer reading sleb128 value"));
+ return buf;
+}
- *r = result;
+const gdb_byte *
+safe_skip_leb128 (const gdb_byte *buf, const gdb_byte *buf_end)
+{
+ buf = gdb_skip_leb128 (buf, buf_end);
+ if (buf == NULL)
+ error (_("DWARF expression error: ran off end of buffer reading leb128 value"));
return buf;
}
\f
size. */
static struct type *
-dwarf_get_base_type (struct dwarf_expr_context *ctx, ULONGEST die, int size)
+dwarf_get_base_type (struct dwarf_expr_context *ctx, cu_offset die, int size)
{
struct type *result;
- if (ctx->get_base_type)
+ if (ctx->funcs->get_base_type)
{
- result = ctx->get_base_type (ctx, die);
+ 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)
return result;
}
+/* If <BUF..BUF_END] contains DW_FORM_block* with single DW_OP_reg* return the
+ DWARF register number. Otherwise return -1. */
+
+int
+dwarf_block_to_dwarf_reg (const gdb_byte *buf, const gdb_byte *buf_end)
+{
+ uint64_t dwarf_reg;
+
+ if (buf_end <= buf)
+ return -1;
+ if (*buf >= DW_OP_reg0 && *buf <= DW_OP_reg31)
+ {
+ if (buf_end - buf != 1)
+ return -1;
+ return *buf - DW_OP_reg0;
+ }
+
+ if (*buf == DW_OP_GNU_regval_type)
+ {
+ buf++;
+ buf = gdb_read_uleb128 (buf, buf_end, &dwarf_reg);
+ if (buf == NULL)
+ return -1;
+ buf = gdb_skip_leb128 (buf, buf_end);
+ if (buf == NULL)
+ return -1;
+ }
+ else if (*buf == DW_OP_regx)
+ {
+ buf++;
+ buf = gdb_read_uleb128 (buf, buf_end, &dwarf_reg);
+ if (buf == NULL)
+ return -1;
+ }
+ else
+ return -1;
+ if (buf != buf_end || (int) dwarf_reg != dwarf_reg)
+ return -1;
+ return dwarf_reg;
+}
+
+/* If <BUF..BUF_END] contains DW_FORM_block* with just DW_OP_breg*(0) and
+ DW_OP_deref* return the DWARF register number. Otherwise return -1.
+ DEREF_SIZE_RETURN contains -1 for DW_OP_deref; otherwise it contains the
+ size from DW_OP_deref_size. */
+
+int
+dwarf_block_to_dwarf_reg_deref (const gdb_byte *buf, const gdb_byte *buf_end,
+ CORE_ADDR *deref_size_return)
+{
+ uint64_t dwarf_reg;
+ int64_t offset;
+
+ if (buf_end <= buf)
+ return -1;
+
+ if (*buf >= DW_OP_breg0 && *buf <= DW_OP_breg31)
+ {
+ dwarf_reg = *buf - DW_OP_breg0;
+ buf++;
+ if (buf >= buf_end)
+ return -1;
+ }
+ else if (*buf == DW_OP_bregx)
+ {
+ buf++;
+ buf = gdb_read_uleb128 (buf, buf_end, &dwarf_reg);
+ if (buf == NULL)
+ return -1;
+ if ((int) dwarf_reg != dwarf_reg)
+ return -1;
+ }
+ else
+ return -1;
+
+ buf = gdb_read_sleb128 (buf, buf_end, &offset);
+ if (buf == NULL)
+ return -1;
+ if (offset != 0)
+ return -1;
+
+ if (*buf == DW_OP_deref)
+ {
+ buf++;
+ *deref_size_return = -1;
+ }
+ else if (*buf == DW_OP_deref_size)
+ {
+ buf++;
+ if (buf >= buf_end)
+ return -1;
+ *deref_size_return = *buf++;
+ }
+ else
+ return -1;
+
+ if (buf != buf_end)
+ return -1;
+
+ return dwarf_reg;
+}
+
+/* If <BUF..BUF_END] contains DW_FORM_block* with single DW_OP_fbreg(X) fill
+ in FB_OFFSET_RETURN with the X offset and return 1. Otherwise return 0. */
+
+int
+dwarf_block_to_fb_offset (const gdb_byte *buf, const gdb_byte *buf_end,
+ CORE_ADDR *fb_offset_return)
+{
+ int64_t fb_offset;
+
+ if (buf_end <= buf)
+ return 0;
+
+ if (*buf != DW_OP_fbreg)
+ return 0;
+ buf++;
+
+ buf = gdb_read_sleb128 (buf, buf_end, &fb_offset);
+ if (buf == NULL)
+ return 0;
+ *fb_offset_return = fb_offset;
+ if (buf != buf_end || fb_offset != (LONGEST) *fb_offset_return)
+ return 0;
+
+ return 1;
+}
+
+/* If <BUF..BUF_END] contains DW_FORM_block* with single DW_OP_bregSP(X) fill
+ in SP_OFFSET_RETURN with the X offset and return 1. Otherwise return 0.
+ The matched SP register number depends on GDBARCH. */
+
+int
+dwarf_block_to_sp_offset (struct gdbarch *gdbarch, const gdb_byte *buf,
+ const gdb_byte *buf_end, CORE_ADDR *sp_offset_return)
+{
+ uint64_t dwarf_reg;
+ int64_t sp_offset;
+
+ if (buf_end <= buf)
+ return 0;
+ if (*buf >= DW_OP_breg0 && *buf <= DW_OP_breg31)
+ {
+ dwarf_reg = *buf - DW_OP_breg0;
+ buf++;
+ }
+ else
+ {
+ if (*buf != DW_OP_bregx)
+ return 0;
+ buf++;
+ buf = gdb_read_uleb128 (buf, buf_end, &dwarf_reg);
+ if (buf == NULL)
+ return 0;
+ }
+
+ if (gdbarch_dwarf2_reg_to_regnum (gdbarch, dwarf_reg)
+ != gdbarch_sp_regnum (gdbarch))
+ return 0;
+
+ buf = gdb_read_sleb128 (buf, buf_end, &sp_offset);
+ if (buf == NULL)
+ return 0;
+ *sp_offset_return = sp_offset;
+ if (buf != buf_end || sp_offset != (LONGEST) *sp_offset_return)
+ return 0;
+
+ return 1;
+}
+
/* The engine for the expression evaluator. Using the context in CTX,
evaluate the expression between OP_PTR and OP_END. */
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;
+ uint64_t uoffset, reg;
+ int64_t offset;
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_lit0:
result_val = value_from_ulongest (address_type, result);
break;
+ case DW_OP_GNU_addr_index:
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, &uoffset);
+ result = (ctx->funcs->get_addr_index) (ctx->baton, uoffset);
+ result_val = value_from_ulongest (address_type, result);
+ break;
+
case DW_OP_const1u:
result = extract_unsigned_integer (op_ptr, 1, 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);
+ op_ptr = safe_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);
+ op_ptr = safe_read_sleb128 (op_ptr, op_end, &offset);
result = offset;
result_val = value_from_ulongest (address_type, result);
break;
break;
case DW_OP_regx:
- op_ptr = read_uleb128 (op_ptr, op_end, ®);
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, ®);
dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_regx");
result = reg;
case DW_OP_implicit_value:
{
- ULONGEST len;
+ uint64_t len;
- op_ptr = read_uleb128 (op_ptr, op_end, &len);
+ op_ptr = safe_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;
case DW_OP_GNU_implicit_pointer:
{
- ULONGEST die;
- LONGEST len;
+ int64_t len;
+
+ if (ctx->ref_addr_size == -1)
+ error (_("DWARF-2 expression error: DW_OP_GNU_implicit_pointer "
+ "is not allowed in frame context"));
- /* The referred-to DIE. */
- ctx->len = extract_unsigned_integer (op_ptr, ctx->addr_size,
+ /* The referred-to DIE of cu_offset kind. */
+ ctx->len = extract_unsigned_integer (op_ptr, ctx->ref_addr_size,
byte_order);
- op_ptr += ctx->addr_size;
+ op_ptr += ctx->ref_addr_size;
/* The byte offset into the data. */
- op_ptr = read_sleb128 (op_ptr, op_end, &len);
+ op_ptr = safe_read_sleb128 (op_ptr, op_end, &len);
result = (ULONGEST) len;
result_val = value_from_ulongest (address_type, result);
case DW_OP_breg30:
case DW_OP_breg31:
{
- op_ptr = read_sleb128 (op_ptr, op_end, &offset);
- result = (ctx->read_reg) (ctx->baton, op - DW_OP_breg0);
+ op_ptr = safe_read_sleb128 (op_ptr, op_end, &offset);
+ 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);
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, ®);
+ op_ptr = safe_read_sleb128 (op_ptr, op_end, &offset);
+ result = (ctx->funcs->read_reg) (ctx->baton, reg);
result += offset;
result_val = value_from_ulongest (address_type, result);
}
size_t datalen;
unsigned int before_stack_len;
- op_ptr = read_sleb128 (op_ptr, op_end, &offset);
+ op_ptr = safe_read_sleb128 (op_ptr, op_end, &offset);
/* Rather than create a whole new context, we simply
record the stack length before execution, then reset it
afterwards, effectively erasing whatever the recursive
/* 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);
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,
- value_as_long (dwarf_expr_fetch (ctx, 0)));
+ 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"));
if (op == DW_OP_GNU_deref_type)
{
- ULONGEST type_die;
+ cu_offset type_die;
- op_ptr = read_uleb128 (op_ptr, op_end, &type_die);
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, &uoffset);
+ type_die.cu_off = uoffset;
type = dwarf_get_base_type (ctx, type_die, 0);
}
else
type = address_type;
- (ctx->read_mem) (ctx->baton, buf, addr, addr_size);
+ (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. */
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, ®);
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, ®);
result += reg;
result_val = value_from_ulongest (address_type, result);
break;
break;
case DW_OP_call_frame_cfa:
- result = (ctx->get_frame_cfa) (ctx->baton);
+ result = (ctx->funcs->get_frame_cfa) (ctx->baton);
result_val = value_from_ulongest (address_type, result);
in_stack_memory = 1;
break;
returned. */
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_piece:
{
- ULONGEST size;
+ uint64_t size;
/* Record the piece. */
- op_ptr = read_uleb128 (op_ptr, op_end, &size);
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, &size);
add_piece (ctx, 8 * size, 0);
/* Pop off the address/regnum, and reset the location
case DW_OP_bit_piece:
{
- ULONGEST size, offset;
+ uint64_t size, offset;
/* Record the piece. */
- op_ptr = read_uleb128 (op_ptr, op_end, &size);
- op_ptr = read_uleb128 (op_ptr, op_end, &offset);
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, &size);
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, &offset);
add_piece (ctx, size, offset);
/* Pop off the address/regnum, and reset the location
goto no_push;
case DW_OP_call2:
- result = extract_unsigned_integer (op_ptr, 2, byte_order);
- op_ptr += 2;
- ctx->dwarf_call (ctx, result);
+ {
+ cu_offset offset;
+
+ offset.cu_off = extract_unsigned_integer (op_ptr, 2, byte_order);
+ op_ptr += 2;
+ ctx->funcs->dwarf_call (ctx, offset);
+ }
goto no_push;
case DW_OP_call4:
- result = extract_unsigned_integer (op_ptr, 4, byte_order);
- op_ptr += 4;
- ctx->dwarf_call (ctx, result);
+ {
+ cu_offset offset;
+
+ offset.cu_off = extract_unsigned_integer (op_ptr, 4, byte_order);
+ op_ptr += 4;
+ ctx->funcs->dwarf_call (ctx, offset);
+ }
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;
+ {
+ uint64_t len;
+ CORE_ADDR deref_size;
+ union call_site_parameter_u kind_u;
+
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, &len);
+ if (op_ptr + len > op_end)
+ error (_("DW_OP_GNU_entry_value: too few bytes available."));
+
+ kind_u.dwarf_reg = dwarf_block_to_dwarf_reg (op_ptr, op_ptr + len);
+ if (kind_u.dwarf_reg != -1)
+ {
+ op_ptr += len;
+ ctx->funcs->push_dwarf_reg_entry_value (ctx,
+ CALL_SITE_PARAMETER_DWARF_REG,
+ kind_u,
+ -1 /* deref_size */);
+ goto no_push;
+ }
+
+ kind_u.dwarf_reg = dwarf_block_to_dwarf_reg_deref (op_ptr,
+ op_ptr + len,
+ &deref_size);
+ if (kind_u.dwarf_reg != -1)
+ {
+ if (deref_size == -1)
+ deref_size = ctx->addr_size;
+ op_ptr += len;
+ ctx->funcs->push_dwarf_reg_entry_value (ctx,
+ CALL_SITE_PARAMETER_DWARF_REG,
+ kind_u, deref_size);
+ goto no_push;
+ }
+
+ error (_("DWARF-2 expression error: DW_OP_GNU_entry_value is "
+ "supported only for single DW_OP_reg* "
+ "or for DW_OP_breg*(0)+DW_OP_deref*"));
+ }
+
+ case DW_OP_GNU_parameter_ref:
+ {
+ union call_site_parameter_u kind_u;
+
+ kind_u.param_offset.cu_off = extract_unsigned_integer (op_ptr, 4,
+ byte_order);
+ op_ptr += 4;
+ ctx->funcs->push_dwarf_reg_entry_value (ctx,
+ CALL_SITE_PARAMETER_PARAM_OFFSET,
+ kind_u,
+ -1 /* deref_size */);
+ }
+ goto no_push;
case DW_OP_GNU_const_type:
{
- ULONGEST type_die;
+ cu_offset type_die;
int n;
const gdb_byte *data;
struct type *type;
- op_ptr = read_uleb128 (op_ptr, op_end, &type_die);
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, &uoffset);
+ type_die.cu_off = uoffset;
n = *op_ptr++;
data = op_ptr;
op_ptr += n;
case DW_OP_GNU_regval_type:
{
- ULONGEST type_die;
+ cu_offset type_die;
struct type *type;
- op_ptr = read_uleb128 (op_ptr, op_end, ®);
- op_ptr = read_uleb128 (op_ptr, op_end, &type_die);
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, ®);
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, &uoffset);
+ type_die.cu_off = uoffset;
type = dwarf_get_base_type (ctx, type_die, 0);
- result = (ctx->read_reg) (ctx->baton, reg);
- result_val = value_from_ulongest (type, result);
+ 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;
+ cu_offset type_die;
struct type *type;
- op_ptr = read_uleb128 (op_ptr, op_end, &type_die);
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, &uoffset);
+ type_die.cu_off = uoffset;
- type = dwarf_get_base_type (ctx, type_die, 0);
+ if (type_die.cu_off == 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);
gdb_assert (ctx->recursion_depth >= 0);
}
+/* 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, cu_offset 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, cu_offset die)
+{
+ error (_("Support for typed DWARF is not supported in this context"));
+}
+
+/* Stub dwarf_expr_context_funcs.push_dwarf_block_entry_value
+ implementation. */
+
+void
+ctx_no_push_dwarf_reg_entry_value (struct dwarf_expr_context *ctx,
+ enum call_site_parameter_kind kind,
+ union call_site_parameter_u kind_u,
+ int deref_size)
+{
+ internal_error (__FILE__, __LINE__,
+ _("Support for DW_OP_GNU_entry_value is unimplemented"));
+}
+
+/* Stub dwarf_expr_context_funcs.get_addr_index implementation. */
+
+CORE_ADDR
+ctx_no_get_addr_index (void *baton, unsigned int index)
+{
+ error (_("%s is invalid in this context"), "DW_OP_GNU_addr_index");
+}
+
+/* Provide a prototype to silence -Wmissing-prototypes. */
+extern initialize_file_ftype _initialize_dwarf2expr;
+
void
_initialize_dwarf2expr (void)
{