/* DWARF 2 Expression Evaluator.
- Copyright (C) 2001-2017 Free Software Foundation, Inc.
+ Copyright (C) 2001-2019 Free Software Foundation, Inc.
Contributed by Daniel Berlin (dan@dberlin.org)
/* Create a new context for the expression evaluator. */
dwarf_expr_context::dwarf_expr_context ()
-: stack (NULL),
- stack_len (0),
- stack_allocated (10),
- gdbarch (NULL),
+: gdbarch (NULL),
addr_size (0),
ref_addr_size (0),
offset (0),
location (DWARF_VALUE_MEMORY),
len (0),
data (NULL),
- initialized (0),
- num_pieces (0),
- pieces (NULL)
+ initialized (0)
{
- this->stack = XNEWVEC (struct dwarf_stack_value, this->stack_allocated);
-}
-
-/* Clean up a dwarf_expr_context. */
-
-dwarf_expr_context::~dwarf_expr_context ()
-{
- xfree (this->stack);
- xfree (this->pieces);
-}
-
-/* Expand the memory allocated stack to contain at least
- NEED more elements than are currently used. */
-
-void
-dwarf_expr_context::grow_stack (size_t need)
-{
- if (this->stack_len + need > this->stack_allocated)
- {
- size_t newlen = this->stack_len + need + 10;
-
- this->stack = XRESIZEVEC (struct dwarf_stack_value, this->stack, newlen);
- this->stack_allocated = newlen;
- }
}
/* Push VALUE onto the stack. */
void
-dwarf_expr_context::push (struct value *value, int in_stack_memory)
+dwarf_expr_context::push (struct value *value, bool in_stack_memory)
{
- struct dwarf_stack_value *v;
-
- grow_stack (1);
- v = &this->stack[this->stack_len++];
- v->value = value;
- v->in_stack_memory = in_stack_memory;
+ stack.emplace_back (value, in_stack_memory);
}
/* Push VALUE onto the stack. */
void
-dwarf_expr_context::push_address (CORE_ADDR value, int in_stack_memory)
+dwarf_expr_context::push_address (CORE_ADDR value, bool in_stack_memory)
{
push (value_from_ulongest (address_type (), value), in_stack_memory);
}
void
dwarf_expr_context::pop ()
{
- if (this->stack_len <= 0)
+ if (stack.empty ())
error (_("dwarf expression stack underflow"));
- this->stack_len--;
+
+ stack.pop_back ();
}
/* Retrieve the N'th item on the stack. */
struct value *
dwarf_expr_context::fetch (int n)
{
- if (this->stack_len <= n)
+ if (stack.size () <= n)
error (_("Asked for position %d of stack, "
- "stack only has %d elements on it."),
- n, this->stack_len);
- return this->stack[this->stack_len - (1 + n)].value;
+ "stack only has %zu elements on it."),
+ n, stack.size ());
+ return stack[stack.size () - (1 + n)].value;
}
/* Require that TYPE be an integral type; throw an exception if not. */
/* Retrieve the in_stack_memory flag of the N'th item on the stack. */
-int
+bool
dwarf_expr_context::fetch_in_stack_memory (int n)
{
- if (this->stack_len <= n)
+ if (stack.size () <= n)
error (_("Asked for position %d of stack, "
- "stack only has %d elements on it."),
- n, this->stack_len);
- return this->stack[this->stack_len - (1 + n)].in_stack_memory;
+ "stack only has %zu elements on it."),
+ n, stack.size ());
+ return stack[stack.size () - (1 + n)].in_stack_memory;
}
/* Return true if the expression stack is empty. */
-int
+bool
dwarf_expr_context::stack_empty_p () const
{
- return this->stack_len == 0;
+ return stack.empty ();
}
/* Add a new piece to the dwarf_expr_context's piece list. */
void
dwarf_expr_context::add_piece (ULONGEST size, ULONGEST offset)
{
- struct dwarf_expr_piece *p;
+ this->pieces.emplace_back ();
+ dwarf_expr_piece &p = this->pieces.back ();
- this->num_pieces++;
+ p.location = this->location;
+ p.size = size;
+ p.offset = offset;
- this->pieces
- = XRESIZEVEC (struct dwarf_expr_piece, this->pieces, this->num_pieces);
-
- p = &this->pieces[this->num_pieces - 1];
- p->location = this->location;
- p->size = size;
- p->offset = offset;
-
- if (p->location == DWARF_VALUE_LITERAL)
+ if (p.location == DWARF_VALUE_LITERAL)
{
- p->v.literal.data = this->data;
- p->v.literal.length = this->len;
+ p.v.literal.data = this->data;
+ p.v.literal.length = this->len;
}
else if (stack_empty_p ())
{
- p->location = DWARF_VALUE_OPTIMIZED_OUT;
+ 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. */
this->location = DWARF_VALUE_OPTIMIZED_OUT;
}
- else if (p->location == DWARF_VALUE_MEMORY)
+ else if (p.location == DWARF_VALUE_MEMORY)
{
- p->v.mem.addr = fetch_address (0);
- p->v.mem.in_stack_memory = fetch_in_stack_memory (0);
+ p.v.mem.addr = fetch_address (0);
+ p.v.mem.in_stack_memory = fetch_in_stack_memory (0);
}
- else if (p->location == DWARF_VALUE_IMPLICIT_POINTER)
+ else if (p.location == DWARF_VALUE_IMPLICIT_POINTER)
{
- p->v.ptr.die_sect_off = (sect_offset) this->len;
- p->v.ptr.offset = value_as_long (fetch (0));
+ p.v.ptr.die_sect_off = (sect_offset) this->len;
+ p.v.ptr.offset = value_as_long (fetch (0));
}
- else if (p->location == DWARF_VALUE_REGISTER)
- p->v.regno = value_as_long (fetch (0));
+ else if (p.location == DWARF_VALUE_REGISTER)
+ p.v.regno = value_as_long (fetch (0));
else
{
- p->v.value = fetch (0);
+ p.v.value = fetch (0);
}
}
enum dwarf_location_atom op = (enum dwarf_location_atom) *op_ptr++;
ULONGEST result;
/* Assume the value is not in stack memory.
- Code that knows otherwise sets this to 1.
+ Code that knows otherwise sets this to true.
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;
+ and leave this as false. */
+ bool in_stack_memory = false;
uint64_t uoffset, reg;
int64_t offset;
struct value *result_val = NULL;
{
const gdb_byte *datastart;
size_t datalen;
- unsigned int before_stack_len;
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
- call put there. */
- before_stack_len = this->stack_len;
+ backup the current stack locally and install a new empty stack,
+ then reset it afterwards, effectively erasing whatever the
+ recursive call put there. */
+ std::vector<dwarf_stack_value> saved_stack = std::move (stack);
+ stack.clear ();
+
/* FIXME: cagney/2003-03-26: This code should be using
get_frame_base_address(), and then implement a dwarf2
specific this_base method. */
"base using explicit value operator"));
result = result + offset;
result_val = value_from_ulongest (address_type, result);
- in_stack_memory = 1;
- this->stack_len = before_stack_len;
+ in_stack_memory = true;
+
+ /* Restore the content of the original stack. */
+ stack = std::move (saved_stack);
+
this->location = DWARF_VALUE_MEMORY;
}
break;
case DW_OP_swap:
{
- struct dwarf_stack_value t1, t2;
-
- if (this->stack_len < 2)
+ if (stack.size () < 2)
error (_("Not enough elements for "
- "DW_OP_swap. Need 2, have %d."),
- this->stack_len);
- t1 = this->stack[this->stack_len - 1];
- t2 = this->stack[this->stack_len - 2];
- this->stack[this->stack_len - 1] = t2;
- this->stack[this->stack_len - 2] = t1;
+ "DW_OP_swap. Need 2, have %zu."),
+ stack.size ());
+
+ dwarf_stack_value &t1 = stack[stack.size () - 1];
+ dwarf_stack_value &t2 = stack[stack.size () - 2];
+ std::swap (t1, t2);
goto no_push;
}
case DW_OP_rot:
{
- struct dwarf_stack_value t1, t2, t3;
-
- if (this->stack_len < 3)
+ if (stack.size () < 3)
error (_("Not enough elements for "
- "DW_OP_rot. Need 3, have %d."),
- this->stack_len);
- t1 = this->stack[this->stack_len - 1];
- t2 = this->stack[this->stack_len - 2];
- t3 = this->stack[this->stack_len - 3];
- this->stack[this->stack_len - 1] = t2;
- this->stack[this->stack_len - 2] = t3;
- this->stack[this->stack_len - 3] = t1;
+ "DW_OP_rot. Need 3, have %zu."),
+ stack.size ());
+
+ dwarf_stack_value temp = stack[stack.size () - 1];
+ stack[stack.size () - 1] = stack[stack.size () - 2];
+ stack[stack.size () - 2] = stack[stack.size () - 3];
+ stack[stack.size () - 3] = temp;
goto no_push;
}
from the type length, we need to zero-extend it. */
if (TYPE_LENGTH (type) != addr_size)
{
- ULONGEST result =
+ ULONGEST datum =
extract_unsigned_integer (buf, addr_size, byte_order);
buf = (gdb_byte *) alloca (TYPE_LENGTH (type));
store_unsigned_integer (buf, TYPE_LENGTH (type),
- byte_order, result);
+ byte_order, datum);
}
result_val = value_from_contents_and_address (type, buf, addr);
case DW_OP_call_frame_cfa:
result = this->get_frame_cfa ();
result_val = value_from_ulongest (address_type, result);
- in_stack_memory = 1;
+ in_stack_memory = true;
break;
case DW_OP_GNU_push_tls_address:
case DW_OP_bit_piece:
{
- uint64_t size, offset;
+ uint64_t size, uleb_offset;
/* Record the piece. */
op_ptr = safe_read_uleb128 (op_ptr, op_end, &size);
- op_ptr = safe_read_uleb128 (op_ptr, op_end, &offset);
- add_piece (size, offset);
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, &uleb_offset);
+ add_piece (size, uleb_offset);
/* Pop off the address/regnum, and reset the location
type. */
this->dwarf_call (cu_off);
}
goto no_push;
+
+ case DW_OP_GNU_variable_value:
+ {
+ sect_offset sect_off
+ = (sect_offset) extract_unsigned_integer (op_ptr,
+ this->ref_addr_size,
+ byte_order);
+ op_ptr += this->ref_addr_size;
+ result_val = this->dwarf_variable_value (sect_off);
+ }
+ break;
case DW_OP_entry_value:
case DW_OP_GNU_entry_value:
if (this->location == DWARF_VALUE_IMPLICIT_POINTER)
add_piece (8 * this->addr_size, 0);
-abort_expression:
this->recursion_depth--;
gdb_assert (this->recursion_depth >= 0);
}