/* DWARF 2 location expression support for GDB.
- Copyright 2003 Free Software Foundation, Inc.
+
+ Copyright (C) 2003, 2005, 2007, 2008, 2009, 2010
+ Free Software Foundation, Inc.
+
Contributed by Daniel Jacobowitz, MontaVista Software, Inc.
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 (at
- your option) any later version.
+ 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, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ 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 "ui-out.h"
#include "gdbcore.h"
#include "target.h"
#include "inferior.h"
+#include "ax.h"
+#include "ax-gdb.h"
+#include "regcache.h"
+#include "objfiles.h"
+#include "exceptions.h"
+#include "block.h"
-#include "elf/dwarf2.h"
+#include "dwarf2.h"
#include "dwarf2expr.h"
#include "dwarf2loc.h"
+#include "dwarf2-frame.h"
#include "gdb_string.h"
+#include "gdb_assert.h"
+
+extern int dwarf2_always_disassemble;
+
+static void
+dwarf_expr_frame_base_1 (struct symbol *framefunc, CORE_ADDR pc,
+ const gdb_byte **start, size_t *length);
+
+/* A helper function for dealing with location lists. Given a
+ symbol baton (BATON) and a pc value (PC), find the appropriate
+ location expression, set *LOCEXPR_LENGTH, and return a pointer
+ to the beginning of the expression. Returns NULL on failure.
+
+ For now, only return the first matching location expression; there
+ can be more than one in the list. */
+
+static const gdb_byte *
+find_location_expression (struct dwarf2_loclist_baton *baton,
+ size_t *locexpr_length, CORE_ADDR pc)
+{
+ CORE_ADDR low, high;
+ const gdb_byte *loc_ptr, *buf_end;
+ int length;
+ struct objfile *objfile = dwarf2_per_cu_objfile (baton->per_cu);
+ struct gdbarch *gdbarch = get_objfile_arch (objfile);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ unsigned int addr_size = dwarf2_per_cu_addr_size (baton->per_cu);
+ int signed_addr_p = bfd_get_sign_extend_vma (objfile->obfd);
+ CORE_ADDR base_mask = ~(~(CORE_ADDR)1 << (addr_size * 8 - 1));
+ /* Adjust base_address for relocatable objects. */
+ CORE_ADDR base_offset = dwarf2_per_cu_text_offset (baton->per_cu);
+ CORE_ADDR base_address = baton->base_address + base_offset;
+
+ loc_ptr = baton->data;
+ buf_end = baton->data + baton->size;
+
+ while (1)
+ {
+ if (buf_end - loc_ptr < 2 * addr_size)
+ error (_("find_location_expression: Corrupted DWARF expression."));
+
+ if (signed_addr_p)
+ low = extract_signed_integer (loc_ptr, addr_size, byte_order);
+ else
+ low = extract_unsigned_integer (loc_ptr, addr_size, byte_order);
+ loc_ptr += addr_size;
+
+ if (signed_addr_p)
+ high = extract_signed_integer (loc_ptr, addr_size, byte_order);
+ else
+ high = extract_unsigned_integer (loc_ptr, addr_size, byte_order);
+ loc_ptr += addr_size;
+
+ /* A base-address-selection entry. */
+ if ((low & base_mask) == base_mask)
+ {
+ base_address = high + base_offset;
+ continue;
+ }
+
+ /* An end-of-list entry. */
+ if (low == 0 && high == 0)
+ return NULL;
-#ifndef DWARF2_REG_TO_REGNUM
-#define DWARF2_REG_TO_REGNUM(REG) (REG)
-#endif
+ /* Otherwise, a location expression entry. */
+ low += base_address;
+ high += base_address;
+
+ length = extract_unsigned_integer (loc_ptr, 2, byte_order);
+ loc_ptr += 2;
+
+ if (pc >= low && pc < high)
+ {
+ *locexpr_length = length;
+ return loc_ptr;
+ }
+
+ loc_ptr += length;
+ }
+}
/* This is the baton used when performing dwarf2 expression
evaluation. */
struct dwarf_expr_baton
{
struct frame_info *frame;
- struct objfile *objfile;
+ struct dwarf2_per_cu_data *per_cu;
};
/* Helper functions for dwarf2_evaluate_loc_desc. */
-/* Using the frame specified in BATON, read register REGNUM. The lval
- type will be returned in LVALP, and for lval_memory the register
- save address will be returned in ADDRP. */
+/* Using the frame specified in BATON, return the value of register
+ REGNUM, treated as a pointer. */
static CORE_ADDR
-dwarf_expr_read_reg (void *baton, int regnum, enum lval_type *lvalp,
- CORE_ADDR *addrp)
+dwarf_expr_read_reg (void *baton, int dwarf_regnum)
{
- CORE_ADDR result;
struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton;
- char *buf = (char *) alloca (MAX_REGISTER_RAW_SIZE);
- int optimized, realnum;
-
- frame_register (debaton->frame, DWARF2_REG_TO_REGNUM (regnum),
- &optimized, lvalp, addrp, &realnum, buf);
- result = extract_address (buf, REGISTER_RAW_SIZE (regnum));
+ struct gdbarch *gdbarch = get_frame_arch (debaton->frame);
+ CORE_ADDR result;
+ int regnum;
+ regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, dwarf_regnum);
+ result = address_from_register (builtin_type (gdbarch)->builtin_data_ptr,
+ regnum, debaton->frame);
return result;
}
/* Read memory at ADDR (length LEN) into BUF. */
static void
-dwarf_expr_read_mem (void *baton, char *buf, CORE_ADDR addr, size_t len)
+dwarf_expr_read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len)
{
read_memory (addr, buf, len);
}
describing the frame base. Return a pointer to it in START and
its length in LENGTH. */
static void
-dwarf_expr_frame_base (void *baton, unsigned char **start, size_t * length)
+dwarf_expr_frame_base (void *baton, const gdb_byte **start, size_t * length)
{
+ /* FIXME: cagney/2003-03-26: This code should be using
+ get_frame_base_address(), and then implement a dwarf2 specific
+ this_base method. */
struct symbol *framefunc;
- struct dwarf2_locexpr_baton *symbaton;
struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton;
- framefunc = get_frame_function (debaton->frame);
- symbaton = SYMBOL_LOCATION_BATON (framefunc);
- *start = symbaton->data;
- *length = symbaton->size;
+
+ /* Use block_linkage_function, which returns a real (not inlined)
+ function, instead of get_frame_function, which may return an
+ inlined function. */
+ framefunc = block_linkage_function (get_frame_block (debaton->frame, NULL));
+
+ /* If we found a frame-relative symbol then it was certainly within
+ some function associated with a frame. If we can't find the frame,
+ something has gone wrong. */
+ gdb_assert (framefunc != NULL);
+
+ dwarf_expr_frame_base_1 (framefunc,
+ get_frame_address_in_block (debaton->frame),
+ start, length);
+}
+
+static void
+dwarf_expr_frame_base_1 (struct symbol *framefunc, CORE_ADDR pc,
+ const gdb_byte **start, size_t *length)
+{
+ if (SYMBOL_LOCATION_BATON (framefunc) == NULL)
+ *start = NULL;
+ else if (SYMBOL_COMPUTED_OPS (framefunc) == &dwarf2_loclist_funcs)
+ {
+ struct dwarf2_loclist_baton *symbaton;
+
+ symbaton = SYMBOL_LOCATION_BATON (framefunc);
+ *start = find_location_expression (symbaton, length, pc);
+ }
+ else
+ {
+ struct dwarf2_locexpr_baton *symbaton;
+
+ symbaton = SYMBOL_LOCATION_BATON (framefunc);
+ if (symbaton != NULL)
+ {
+ *length = symbaton->size;
+ *start = symbaton->data;
+ }
+ else
+ *start = NULL;
+ }
+
+ if (*start == NULL)
+ error (_("Could not find the frame base for \"%s\"."),
+ SYMBOL_NATURAL_NAME (framefunc));
+}
+
+/* Helper function for dwarf2_evaluate_loc_desc. Computes the CFA for
+ the frame in BATON. */
+
+static CORE_ADDR
+dwarf_expr_frame_cfa (void *baton)
+{
+ struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton;
+
+ return dwarf2_frame_cfa (debaton->frame);
}
/* Using the objfile specified in BATON, find the address for the
dwarf_expr_tls_address (void *baton, CORE_ADDR offset)
{
struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton;
- CORE_ADDR addr;
+ struct objfile *objfile = dwarf2_per_cu_objfile (debaton->per_cu);
+
+ return target_translate_tls_address (objfile, offset);
+}
+
+/* Call DWARF subroutine from DW_AT_location of DIE at DIE_OFFSET in current CU
+ (as is PER_CU). State of the CTX is not affected by the call and return. */
+
+static void
+per_cu_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset,
+ struct dwarf2_per_cu_data *per_cu)
+{
+ struct dwarf2_locexpr_baton block;
+
+ block = dwarf2_fetch_die_location_block (die_offset, per_cu);
+
+ /* DW_OP_call_ref is currently not supported. */
+ gdb_assert (block.per_cu == per_cu);
+
+ dwarf_expr_eval (ctx, block.data, block.size);
+}
+
+/* Helper interface of per_cu_dwarf_call for dwarf2_evaluate_loc_desc. */
+
+static void
+dwarf_expr_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset)
+{
+ struct dwarf_expr_baton *debaton = ctx->baton;
+
+ return per_cu_dwarf_call (ctx, die_offset, debaton->per_cu);
+}
+
+struct piece_closure
+{
+ /* Reference count. */
+ int refc;
+
+ /* The number of pieces used to describe this variable. */
+ int n_pieces;
+
+ /* The target address size, used only for DWARF_VALUE_STACK. */
+ int addr_size;
+
+ /* The pieces themselves. */
+ struct dwarf_expr_piece *pieces;
+};
+
+/* Allocate a closure for a value formed from separately-described
+ PIECES. */
+
+static struct piece_closure *
+allocate_piece_closure (int n_pieces, struct dwarf_expr_piece *pieces,
+ int addr_size)
+{
+ struct piece_closure *c = XZALLOC (struct piece_closure);
+
+ c->refc = 1;
+ c->n_pieces = n_pieces;
+ c->addr_size = addr_size;
+ c->pieces = XCALLOC (n_pieces, struct dwarf_expr_piece);
+
+ memcpy (c->pieces, pieces, n_pieces * sizeof (struct dwarf_expr_piece));
+
+ return c;
+}
+
+/* The lowest-level function to extract bits from a byte buffer.
+ SOURCE is the buffer. It is updated if we read to the end of a
+ byte.
+ SOURCE_OFFSET_BITS is the offset of the first bit to read. It is
+ updated to reflect the number of bits actually read.
+ NBITS is the number of bits we want to read. It is updated to
+ reflect the number of bits actually read. This function may read
+ fewer bits.
+ BITS_BIG_ENDIAN is taken directly from gdbarch.
+ This function returns the extracted bits. */
+
+static unsigned int
+extract_bits_primitive (const gdb_byte **source,
+ unsigned int *source_offset_bits,
+ int *nbits, int bits_big_endian)
+{
+ unsigned int avail, mask, datum;
+
+ gdb_assert (*source_offset_bits < 8);
+
+ avail = 8 - *source_offset_bits;
+ if (avail > *nbits)
+ avail = *nbits;
+
+ mask = (1 << avail) - 1;
+ datum = **source;
+ if (bits_big_endian)
+ datum >>= 8 - (*source_offset_bits + *nbits);
+ else
+ datum >>= *source_offset_bits;
+ datum &= mask;
+
+ *nbits -= avail;
+ *source_offset_bits += avail;
+ if (*source_offset_bits >= 8)
+ {
+ *source_offset_bits -= 8;
+ ++*source;
+ }
+
+ return datum;
+}
+
+/* Extract some bits from a source buffer and move forward in the
+ buffer.
+
+ SOURCE is the source buffer. It is updated as bytes are read.
+ SOURCE_OFFSET_BITS is the offset into SOURCE. It is updated as
+ bits are read.
+ NBITS is the number of bits to read.
+ BITS_BIG_ENDIAN is taken directly from gdbarch.
+
+ This function returns the bits that were read. */
+
+static unsigned int
+extract_bits (const gdb_byte **source, unsigned int *source_offset_bits,
+ int nbits, int bits_big_endian)
+{
+ unsigned int datum;
+
+ gdb_assert (nbits > 0 && nbits <= 8);
+
+ datum = extract_bits_primitive (source, source_offset_bits, &nbits,
+ bits_big_endian);
+ if (nbits > 0)
+ {
+ unsigned int more;
+
+ more = extract_bits_primitive (source, source_offset_bits, &nbits,
+ bits_big_endian);
+ if (bits_big_endian)
+ datum <<= nbits;
+ else
+ more <<= nbits;
+ datum |= more;
+ }
+
+ return datum;
+}
+
+/* Write some bits into a buffer and move forward in the buffer.
+
+ DATUM is the bits to write. The low-order bits of DATUM are used.
+ DEST is the destination buffer. It is updated as bytes are
+ written.
+ DEST_OFFSET_BITS is the bit offset in DEST at which writing is
+ done.
+ NBITS is the number of valid bits in DATUM.
+ BITS_BIG_ENDIAN is taken directly from gdbarch. */
+
+static void
+insert_bits (unsigned int datum,
+ gdb_byte *dest, unsigned int dest_offset_bits,
+ int nbits, int bits_big_endian)
+{
+ unsigned int mask;
+
+ gdb_assert (dest_offset_bits >= 0 && dest_offset_bits + nbits <= 8);
+
+ mask = (1 << nbits) - 1;
+ if (bits_big_endian)
+ {
+ datum <<= 8 - (dest_offset_bits + nbits);
+ mask <<= 8 - (dest_offset_bits + nbits);
+ }
+ else
+ {
+ datum <<= dest_offset_bits;
+ mask <<= dest_offset_bits;
+ }
+
+ gdb_assert ((datum & ~mask) == 0);
+
+ *dest = (*dest & ~mask) | datum;
+}
+
+/* Copy bits from a source to a destination.
+
+ DEST is where the bits should be written.
+ DEST_OFFSET_BITS is the bit offset into DEST.
+ SOURCE is the source of bits.
+ SOURCE_OFFSET_BITS is the bit offset into SOURCE.
+ BIT_COUNT is the number of bits to copy.
+ BITS_BIG_ENDIAN is taken directly from gdbarch. */
+
+static void
+copy_bitwise (gdb_byte *dest, unsigned int dest_offset_bits,
+ const gdb_byte *source, unsigned int source_offset_bits,
+ unsigned int bit_count,
+ int bits_big_endian)
+{
+ unsigned int dest_avail;
+ int datum;
+
+ /* Reduce everything to byte-size pieces. */
+ dest += dest_offset_bits / 8;
+ dest_offset_bits %= 8;
+ source += source_offset_bits / 8;
+ source_offset_bits %= 8;
+
+ dest_avail = 8 - dest_offset_bits % 8;
+
+ /* See if we can fill the first destination byte. */
+ if (dest_avail < bit_count)
+ {
+ datum = extract_bits (&source, &source_offset_bits, dest_avail,
+ bits_big_endian);
+ insert_bits (datum, dest, dest_offset_bits, dest_avail, bits_big_endian);
+ ++dest;
+ dest_offset_bits = 0;
+ bit_count -= dest_avail;
+ }
+
+ /* Now, either DEST_OFFSET_BITS is byte-aligned, or we have fewer
+ than 8 bits remaining. */
+ gdb_assert (dest_offset_bits % 8 == 0 || bit_count < 8);
+ for (; bit_count >= 8; bit_count -= 8)
+ {
+ datum = extract_bits (&source, &source_offset_bits, 8, bits_big_endian);
+ *dest++ = (gdb_byte) datum;
+ }
+
+ /* Finally, we may have a few leftover bits. */
+ gdb_assert (bit_count <= 8 - dest_offset_bits % 8);
+ if (bit_count > 0)
+ {
+ datum = extract_bits (&source, &source_offset_bits, bit_count,
+ bits_big_endian);
+ insert_bits (datum, dest, dest_offset_bits, bit_count, bits_big_endian);
+ }
+}
+
+static void
+read_pieced_value (struct value *v)
+{
+ int i;
+ long offset = 0;
+ ULONGEST bits_to_skip;
+ gdb_byte *contents;
+ struct piece_closure *c = (struct piece_closure *) value_computed_closure (v);
+ struct frame_info *frame = frame_find_by_id (VALUE_FRAME_ID (v));
+ size_t type_len;
+ size_t buffer_size = 0;
+ char *buffer = NULL;
+ struct cleanup *cleanup;
+ int bits_big_endian
+ = gdbarch_bits_big_endian (get_type_arch (value_type (v)));
+
+ if (value_type (v) != value_enclosing_type (v))
+ internal_error (__FILE__, __LINE__,
+ _("Should not be able to create a lazy value with "
+ "an enclosing type"));
+
+ cleanup = make_cleanup (free_current_contents, &buffer);
+
+ contents = value_contents_raw (v);
+ bits_to_skip = 8 * value_offset (v);
+ if (value_bitsize (v))
+ {
+ bits_to_skip += value_bitpos (v);
+ type_len = value_bitsize (v);
+ }
+ else
+ type_len = 8 * TYPE_LENGTH (value_type (v));
+
+ for (i = 0; i < c->n_pieces && offset < type_len; i++)
+ {
+ struct dwarf_expr_piece *p = &c->pieces[i];
+ size_t this_size, this_size_bits;
+ long dest_offset_bits, source_offset_bits, source_offset;
+ const gdb_byte *intermediate_buffer;
+
+ /* Compute size, source, and destination offsets for copying, in
+ bits. */
+ this_size_bits = p->size;
+ if (bits_to_skip > 0 && bits_to_skip >= this_size_bits)
+ {
+ bits_to_skip -= this_size_bits;
+ continue;
+ }
+ if (this_size_bits > type_len - offset)
+ this_size_bits = type_len - offset;
+ if (bits_to_skip > 0)
+ {
+ dest_offset_bits = 0;
+ source_offset_bits = bits_to_skip;
+ this_size_bits -= bits_to_skip;
+ bits_to_skip = 0;
+ }
+ else
+ {
+ dest_offset_bits = offset;
+ source_offset_bits = 0;
+ }
+
+ this_size = (this_size_bits + source_offset_bits % 8 + 7) / 8;
+ source_offset = source_offset_bits / 8;
+ if (buffer_size < this_size)
+ {
+ buffer_size = this_size;
+ buffer = xrealloc (buffer, buffer_size);
+ }
+ intermediate_buffer = buffer;
+
+ /* Copy from the source to DEST_BUFFER. */
+ switch (p->location)
+ {
+ case DWARF_VALUE_REGISTER:
+ {
+ struct gdbarch *arch = get_frame_arch (frame);
+ int gdb_regnum = gdbarch_dwarf2_reg_to_regnum (arch, p->v.value);
+ int reg_offset = source_offset;
+
+ if (gdbarch_byte_order (arch) == BFD_ENDIAN_BIG
+ && this_size < register_size (arch, gdb_regnum))
+ {
+ /* Big-endian, and we want less than full size. */
+ reg_offset = register_size (arch, gdb_regnum) - this_size;
+ /* We want the lower-order THIS_SIZE_BITS of the bytes
+ we extract from the register. */
+ source_offset_bits += 8 * this_size - this_size_bits;
+ }
+
+ if (gdb_regnum != -1)
+ {
+ get_frame_register_bytes (frame, gdb_regnum, reg_offset,
+ this_size, buffer);
+ }
+ else
+ {
+ error (_("Unable to access DWARF register number %s"),
+ paddress (arch, p->v.value));
+ }
+ }
+ break;
+
+ case DWARF_VALUE_MEMORY:
+ if (p->v.mem.in_stack_memory)
+ read_stack (p->v.mem.addr + source_offset, buffer, this_size);
+ else
+ read_memory (p->v.mem.addr + source_offset, buffer, this_size);
+ break;
+
+ case DWARF_VALUE_STACK:
+ {
+ struct gdbarch *gdbarch = get_type_arch (value_type (v));
+ size_t n = this_size;
+
+ if (n > c->addr_size - source_offset)
+ n = (c->addr_size >= source_offset
+ ? c->addr_size - source_offset
+ : 0);
+ if (n == 0)
+ {
+ /* Nothing. */
+ }
+ else if (source_offset == 0)
+ store_unsigned_integer (buffer, n,
+ gdbarch_byte_order (gdbarch),
+ p->v.value);
+ else
+ {
+ gdb_byte bytes[sizeof (ULONGEST)];
+
+ store_unsigned_integer (bytes, n + source_offset,
+ gdbarch_byte_order (gdbarch),
+ p->v.value);
+ memcpy (buffer, bytes + source_offset, n);
+ }
+ }
+ break;
+
+ case DWARF_VALUE_LITERAL:
+ {
+ size_t n = this_size;
+
+ if (n > p->v.literal.length - source_offset)
+ n = (p->v.literal.length >= source_offset
+ ? p->v.literal.length - source_offset
+ : 0);
+ if (n != 0)
+ intermediate_buffer = p->v.literal.data + source_offset;
+ }
+ break;
+
+ case DWARF_VALUE_OPTIMIZED_OUT:
+ set_value_optimized_out (v, 1);
+ break;
+
+ default:
+ internal_error (__FILE__, __LINE__, _("invalid location type"));
+ }
+
+ if (p->location != DWARF_VALUE_OPTIMIZED_OUT)
+ copy_bitwise (contents, dest_offset_bits,
+ intermediate_buffer, source_offset_bits % 8,
+ this_size_bits, bits_big_endian);
+
+ offset += this_size_bits;
+ }
+
+ do_cleanups (cleanup);
+}
+
+static void
+write_pieced_value (struct value *to, struct value *from)
+{
+ int i;
+ long offset = 0;
+ ULONGEST bits_to_skip;
+ const gdb_byte *contents;
+ struct piece_closure *c = (struct piece_closure *) value_computed_closure (to);
+ struct frame_info *frame = frame_find_by_id (VALUE_FRAME_ID (to));
+ size_t type_len;
+ size_t buffer_size = 0;
+ char *buffer = NULL;
+ struct cleanup *cleanup;
+ int bits_big_endian
+ = gdbarch_bits_big_endian (get_type_arch (value_type (to)));
+
+ if (frame == NULL)
+ {
+ set_value_optimized_out (to, 1);
+ return;
+ }
- if (target_get_thread_local_address_p ())
- addr = target_get_thread_local_address (inferior_ptid,
- debaton->objfile,
- offset);
+ cleanup = make_cleanup (free_current_contents, &buffer);
+
+ contents = value_contents (from);
+ bits_to_skip = 8 * value_offset (to);
+ if (value_bitsize (to))
+ {
+ bits_to_skip += value_bitpos (to);
+ type_len = value_bitsize (to);
+ }
else
- error ("Cannot find thread-local variables on this target");
+ type_len = 8 * TYPE_LENGTH (value_type (to));
+
+ for (i = 0; i < c->n_pieces && offset < type_len; i++)
+ {
+ struct dwarf_expr_piece *p = &c->pieces[i];
+ size_t this_size_bits, this_size;
+ long dest_offset_bits, source_offset_bits, dest_offset, source_offset;
+ int need_bitwise;
+ const gdb_byte *source_buffer;
+
+ this_size_bits = p->size;
+ if (bits_to_skip > 0 && bits_to_skip >= this_size_bits)
+ {
+ bits_to_skip -= this_size_bits;
+ continue;
+ }
+ if (this_size_bits > type_len - offset)
+ this_size_bits = type_len - offset;
+ if (bits_to_skip > 0)
+ {
+ dest_offset_bits = bits_to_skip;
+ source_offset_bits = 0;
+ this_size_bits -= bits_to_skip;
+ bits_to_skip = 0;
+ }
+ else
+ {
+ dest_offset_bits = 0;
+ source_offset_bits = offset;
+ }
+
+ this_size = (this_size_bits + source_offset_bits % 8 + 7) / 8;
+ source_offset = source_offset_bits / 8;
+ dest_offset = dest_offset_bits / 8;
+ if (dest_offset_bits % 8 == 0 && source_offset_bits % 8 == 0)
+ {
+ source_buffer = contents + source_offset;
+ need_bitwise = 0;
+ }
+ else
+ {
+ if (buffer_size < this_size)
+ {
+ buffer_size = this_size;
+ buffer = xrealloc (buffer, buffer_size);
+ }
+ source_buffer = buffer;
+ need_bitwise = 1;
+ }
+
+ switch (p->location)
+ {
+ case DWARF_VALUE_REGISTER:
+ {
+ struct gdbarch *arch = get_frame_arch (frame);
+ int gdb_regnum = gdbarch_dwarf2_reg_to_regnum (arch, p->v.value);
+ int reg_offset = dest_offset;
+
+ if (gdbarch_byte_order (arch) == BFD_ENDIAN_BIG
+ && this_size <= register_size (arch, gdb_regnum))
+ /* Big-endian, and we want less than full size. */
+ reg_offset = register_size (arch, gdb_regnum) - this_size;
+
+ if (gdb_regnum != -1)
+ {
+ if (need_bitwise)
+ {
+ get_frame_register_bytes (frame, gdb_regnum, reg_offset,
+ this_size, buffer);
+ copy_bitwise (buffer, dest_offset_bits,
+ contents, source_offset_bits,
+ this_size_bits,
+ bits_big_endian);
+ }
+
+ put_frame_register_bytes (frame, gdb_regnum, reg_offset,
+ this_size, source_buffer);
+ }
+ else
+ {
+ error (_("Unable to write to DWARF register number %s"),
+ paddress (arch, p->v.value));
+ }
+ }
+ break;
+ case DWARF_VALUE_MEMORY:
+ if (need_bitwise)
+ {
+ /* Only the first and last bytes can possibly have any
+ bits reused. */
+ read_memory (p->v.mem.addr + dest_offset, buffer, 1);
+ read_memory (p->v.mem.addr + dest_offset + this_size - 1,
+ buffer + this_size - 1, 1);
+ copy_bitwise (buffer, dest_offset_bits,
+ contents, source_offset_bits,
+ this_size_bits,
+ bits_big_endian);
+ }
+
+ write_memory (p->v.mem.addr + dest_offset,
+ source_buffer, this_size);
+ break;
+ default:
+ set_value_optimized_out (to, 1);
+ break;
+ }
+ offset += this_size_bits;
+ }
+
+ do_cleanups (cleanup);
+}
+
+static int
+check_pieced_value_bits (const struct value *value, int bit_offset,
+ int bit_length, int validity)
+{
+ struct piece_closure *c
+ = (struct piece_closure *) value_computed_closure (value);
+ int i;
+
+ bit_offset += 8 * value_offset (value);
+ if (value_bitsize (value))
+ bit_offset += value_bitpos (value);
+
+ for (i = 0; i < c->n_pieces && bit_length > 0; i++)
+ {
+ struct dwarf_expr_piece *p = &c->pieces[i];
+ size_t this_size_bits = p->size;
+
+ if (bit_offset > 0)
+ {
+ if (bit_offset >= this_size_bits)
+ {
+ bit_offset -= this_size_bits;
+ continue;
+ }
+
+ bit_length -= this_size_bits - bit_offset;
+ bit_offset = 0;
+ }
+ else
+ bit_length -= this_size_bits;
+
+ if (p->location == DWARF_VALUE_OPTIMIZED_OUT)
+ {
+ if (validity)
+ return 0;
+ }
+ else
+ {
+ if (!validity)
+ return 1;
+ }
+ }
+
+ return validity;
+}
+
+static int
+check_pieced_value_validity (const struct value *value, int bit_offset,
+ int bit_length)
+{
+ return check_pieced_value_bits (value, bit_offset, bit_length, 1);
+}
+
+static int
+check_pieced_value_invalid (const struct value *value)
+{
+ return check_pieced_value_bits (value, 0,
+ 8 * TYPE_LENGTH (value_type (value)), 0);
+}
+
+static void *
+copy_pieced_value_closure (const struct value *v)
+{
+ struct piece_closure *c = (struct piece_closure *) value_computed_closure (v);
+
+ ++c->refc;
+ return c;
+}
- return addr;
+static void
+free_pieced_value_closure (struct value *v)
+{
+ struct piece_closure *c = (struct piece_closure *) value_computed_closure (v);
+
+ --c->refc;
+ if (c->refc == 0)
+ {
+ xfree (c->pieces);
+ xfree (c);
+ }
}
+/* Functions for accessing a variable described by DW_OP_piece. */
+static struct lval_funcs pieced_value_funcs = {
+ read_pieced_value,
+ write_pieced_value,
+ check_pieced_value_validity,
+ check_pieced_value_invalid,
+ copy_pieced_value_closure,
+ free_pieced_value_closure
+};
+
/* Evaluate a location description, starting at DATA and with length
- SIZE, to find the current location of variable VAR in the context
+ SIZE, to find the current location of variable of TYPE in the context
of FRAME. */
-static struct value *
-dwarf2_evaluate_loc_desc (struct symbol *var, struct frame_info *frame,
- unsigned char *data, unsigned short size,
- struct objfile *objfile)
+
+struct value *
+dwarf2_evaluate_loc_desc (struct type *type, struct frame_info *frame,
+ const gdb_byte *data, unsigned short size,
+ struct dwarf2_per_cu_data *per_cu)
{
- CORE_ADDR result;
struct value *retval;
struct dwarf_expr_baton baton;
struct dwarf_expr_context *ctx;
+ struct cleanup *old_chain;
+ struct objfile *objfile = dwarf2_per_cu_objfile (per_cu);
+
+ if (size == 0)
+ {
+ retval = allocate_value (type);
+ VALUE_LVAL (retval) = not_lval;
+ set_value_optimized_out (retval, 1);
+ return retval;
+ }
baton.frame = frame;
- baton.objfile = objfile;
+ baton.per_cu = per_cu;
ctx = new_dwarf_expr_context ();
+ old_chain = make_cleanup_free_dwarf_expr_context (ctx);
+
+ ctx->gdbarch = get_objfile_arch (objfile);
+ ctx->addr_size = dwarf2_per_cu_addr_size (per_cu);
+ ctx->offset = dwarf2_per_cu_text_offset (per_cu);
ctx->baton = &baton;
ctx->read_reg = dwarf_expr_read_reg;
ctx->read_mem = dwarf_expr_read_mem;
ctx->get_frame_base = dwarf_expr_frame_base;
+ ctx->get_frame_cfa = dwarf_expr_frame_cfa;
ctx->get_tls_address = dwarf_expr_tls_address;
+ ctx->dwarf_call = dwarf_expr_dwarf_call;
dwarf_expr_eval (ctx, data, size);
-
- retval = allocate_value (SYMBOL_TYPE (var));
- VALUE_BFD_SECTION (retval) = SYMBOL_BFD_SECTION (var);
-
- if (ctx->in_reg)
+ if (ctx->num_pieces > 0)
{
- store_unsigned_integer (VALUE_CONTENTS_RAW (retval),
- TYPE_LENGTH (SYMBOL_TYPE (var)),
- dwarf_expr_fetch (ctx, 0));
- VALUE_LVAL (retval) = lval_register;
- VALUE_REGNO (retval) = ctx->regnum;
+ struct piece_closure *c;
+ struct frame_id frame_id = get_frame_id (frame);
+
+ c = allocate_piece_closure (ctx->num_pieces, ctx->pieces,
+ ctx->addr_size);
+ retval = allocate_computed_value (type, &pieced_value_funcs, c);
+ VALUE_FRAME_ID (retval) = frame_id;
}
else
{
- result = dwarf_expr_fetch (ctx, 0);
- VALUE_LVAL (retval) = lval_memory;
- VALUE_LAZY (retval) = 1;
- VALUE_ADDRESS (retval) = result;
- }
+ switch (ctx->location)
+ {
+ case DWARF_VALUE_REGISTER:
+ {
+ struct gdbarch *arch = get_frame_arch (frame);
+ ULONGEST dwarf_regnum = dwarf_expr_fetch (ctx, 0);
+ int gdb_regnum = gdbarch_dwarf2_reg_to_regnum (arch, dwarf_regnum);
- free_dwarf_expr_context (ctx);
+ if (gdb_regnum != -1)
+ retval = value_from_register (type, gdb_regnum, frame);
+ else
+ error (_("Unable to access DWARF register number %s"),
+ paddress (arch, dwarf_regnum));
+ }
+ break;
- return retval;
-}
+ case DWARF_VALUE_MEMORY:
+ {
+ CORE_ADDR address = dwarf_expr_fetch_address (ctx, 0);
+ int in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 0);
+
+ retval = allocate_value (type);
+ VALUE_LVAL (retval) = lval_memory;
+ set_value_lazy (retval, 1);
+ if (in_stack_memory)
+ set_value_stack (retval, 1);
+ set_value_address (retval, address);
+ }
+ break;
+
+ case DWARF_VALUE_STACK:
+ {
+ ULONGEST value = dwarf_expr_fetch (ctx, 0);
+ bfd_byte *contents;
+ size_t n = ctx->addr_size;
+
+ retval = allocate_value (type);
+ contents = value_contents_raw (retval);
+ if (n > TYPE_LENGTH (type))
+ n = TYPE_LENGTH (type);
+ store_unsigned_integer (contents, n,
+ gdbarch_byte_order (ctx->gdbarch),
+ value);
+ }
+ break;
+
+ case DWARF_VALUE_LITERAL:
+ {
+ bfd_byte *contents;
+ size_t n = ctx->len;
+ retval = allocate_value (type);
+ contents = value_contents_raw (retval);
+ if (n > TYPE_LENGTH (type))
+ n = TYPE_LENGTH (type);
+ memcpy (contents, ctx->data, n);
+ }
+ break;
+ /* DWARF_VALUE_OPTIMIZED_OUT can't occur in this context --
+ it can only be encountered when making a piece. */
+ case DWARF_VALUE_OPTIMIZED_OUT:
+ default:
+ internal_error (__FILE__, __LINE__, _("invalid location type"));
+ }
+ }
+
+ set_value_initialized (retval, ctx->initialized);
+ do_cleanups (old_chain);
+ return retval;
+}
\f
/* Helper functions and baton for dwarf2_loc_desc_needs_frame. */
struct needs_frame_baton
{
int needs_frame;
+ struct dwarf2_per_cu_data *per_cu;
};
/* Reads from registers do require a frame. */
static CORE_ADDR
-needs_frame_read_reg (void *baton, int regnum, enum lval_type *lvalp,
- CORE_ADDR *addrp)
+needs_frame_read_reg (void *baton, int regnum)
{
struct needs_frame_baton *nf_baton = baton;
+
nf_baton->needs_frame = 1;
return 1;
}
/* Reads from memory do not require a frame. */
static void
-needs_frame_read_mem (void *baton, char *buf, CORE_ADDR addr, size_t len)
+needs_frame_read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len)
{
memset (buf, 0, len);
}
/* Frame-relative accesses do require a frame. */
static void
-needs_frame_frame_base (void *baton, unsigned char **start, size_t * length)
+needs_frame_frame_base (void *baton, const gdb_byte **start, size_t * length)
{
- static char lit0 = DW_OP_lit0;
+ static gdb_byte lit0 = DW_OP_lit0;
struct needs_frame_baton *nf_baton = baton;
*start = &lit0;
nf_baton->needs_frame = 1;
}
+/* CFA accesses require a frame. */
+
+static CORE_ADDR
+needs_frame_frame_cfa (void *baton)
+{
+ struct needs_frame_baton *nf_baton = baton;
+
+ nf_baton->needs_frame = 1;
+ return 1;
+}
+
/* Thread-local accesses do require a frame. */
static CORE_ADDR
needs_frame_tls_address (void *baton, CORE_ADDR offset)
{
struct needs_frame_baton *nf_baton = baton;
+
nf_baton->needs_frame = 1;
return 1;
}
+/* Helper interface of per_cu_dwarf_call for dwarf2_loc_desc_needs_frame. */
+
+static void
+needs_frame_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset)
+{
+ struct needs_frame_baton *nf_baton = ctx->baton;
+
+ return per_cu_dwarf_call (ctx, die_offset, nf_baton->per_cu);
+}
+
/* Return non-zero iff the location expression at DATA (length SIZE)
requires a frame to evaluate. */
static int
-dwarf2_loc_desc_needs_frame (unsigned char *data, unsigned short size)
+dwarf2_loc_desc_needs_frame (const gdb_byte *data, unsigned short size,
+ struct dwarf2_per_cu_data *per_cu)
{
struct needs_frame_baton baton;
struct dwarf_expr_context *ctx;
+ int in_reg;
+ struct cleanup *old_chain;
+ struct objfile *objfile = dwarf2_per_cu_objfile (per_cu);
baton.needs_frame = 0;
+ baton.per_cu = per_cu;
ctx = new_dwarf_expr_context ();
+ old_chain = make_cleanup_free_dwarf_expr_context (ctx);
+
+ ctx->gdbarch = get_objfile_arch (objfile);
+ ctx->addr_size = dwarf2_per_cu_addr_size (per_cu);
+ ctx->offset = dwarf2_per_cu_text_offset (per_cu);
ctx->baton = &baton;
ctx->read_reg = needs_frame_read_reg;
ctx->read_mem = needs_frame_read_mem;
ctx->get_frame_base = needs_frame_frame_base;
+ ctx->get_frame_cfa = needs_frame_frame_cfa;
ctx->get_tls_address = needs_frame_tls_address;
+ ctx->dwarf_call = needs_frame_dwarf_call;
dwarf_expr_eval (ctx, data, size);
- free_dwarf_expr_context (ctx);
+ in_reg = ctx->location == DWARF_VALUE_REGISTER;
+
+ if (ctx->num_pieces > 0)
+ {
+ int i;
+
+ /* If the location has several pieces, and any of them are in
+ registers, then we will need a frame to fetch them from. */
+ for (i = 0; i < ctx->num_pieces; i++)
+ if (ctx->pieces[i].location == DWARF_VALUE_REGISTER)
+ in_reg = 1;
+ }
+
+ do_cleanups (old_chain);
- return baton.needs_frame;
+ return baton.needs_frame || in_reg;
}
+/* A helper function that throws an unimplemented error mentioning a
+ given DWARF operator. */
+static void
+unimplemented (unsigned int op)
+{
+ error (_("DWARF operator %s cannot be translated to an agent expression"),
+ dwarf_stack_op_name (op, 1));
+}
-\f
-/* Return the value of SYMBOL in FRAME using the DWARF-2 expression
+/* A helper function to convert a DWARF register to an arch register.
+ ARCH is the architecture.
+ DWARF_REG is the register.
+ This will throw an exception if the DWARF register cannot be
+ translated to an architecture register. */
+
+static int
+translate_register (struct gdbarch *arch, int dwarf_reg)
+{
+ int reg = gdbarch_dwarf2_reg_to_regnum (arch, dwarf_reg);
+ if (reg == -1)
+ error (_("Unable to access DWARF register number %d"), dwarf_reg);
+ return reg;
+}
+
+/* A helper function that emits an access to memory. ARCH is the
+ target architecture. EXPR is the expression which we are building.
+ NBITS is the number of bits we want to read. This emits the
+ opcodes needed to read the memory and then extract the desired
+ bits. */
+
+static void
+access_memory (struct gdbarch *arch, struct agent_expr *expr, ULONGEST nbits)
+{
+ ULONGEST nbytes = (nbits + 7) / 8;
+
+ gdb_assert (nbits > 0 && nbits <= sizeof (LONGEST));
+
+ if (trace_kludge)
+ ax_trace_quick (expr, nbytes);
+
+ if (nbits <= 8)
+ ax_simple (expr, aop_ref8);
+ else if (nbits <= 16)
+ ax_simple (expr, aop_ref16);
+ else if (nbits <= 32)
+ ax_simple (expr, aop_ref32);
+ else
+ ax_simple (expr, aop_ref64);
+
+ /* If we read exactly the number of bytes we wanted, we're done. */
+ if (8 * nbytes == nbits)
+ return;
+
+ if (gdbarch_bits_big_endian (arch))
+ {
+ /* On a bits-big-endian machine, we want the high-order
+ NBITS. */
+ ax_const_l (expr, 8 * nbytes - nbits);
+ ax_simple (expr, aop_rsh_unsigned);
+ }
+ else
+ {
+ /* On a bits-little-endian box, we want the low-order NBITS. */
+ ax_zero_ext (expr, nbits);
+ }
+}
+
+/* Compile a DWARF location expression to an agent expression.
+
+ EXPR is the agent expression we are building.
+ LOC is the agent value we modify.
+ ARCH is the architecture.
+ ADDR_SIZE is the size of addresses, in bytes.
+ OP_PTR is the start of the location expression.
+ OP_END is one past the last byte of the location expression.
+
+ This will throw an exception for various kinds of errors -- for
+ example, if the expression cannot be compiled, or if the expression
+ is invalid. */
+
+static void
+compile_dwarf_to_ax (struct agent_expr *expr, struct axs_value *loc,
+ struct gdbarch *arch, unsigned int addr_size,
+ const gdb_byte *op_ptr, const gdb_byte *op_end,
+ struct dwarf2_per_cu_data *per_cu)
+{
+ struct cleanup *cleanups;
+ int i, *offsets;
+ VEC(int) *dw_labels = NULL, *patches = NULL;
+ const gdb_byte * const base = op_ptr;
+ const gdb_byte *previous_piece = op_ptr;
+ enum bfd_endian byte_order = gdbarch_byte_order (arch);
+ ULONGEST bits_collected = 0;
+ unsigned int addr_size_bits = 8 * addr_size;
+ int bits_big_endian = gdbarch_bits_big_endian (arch);
+
+ offsets = xmalloc ((op_end - op_ptr) * sizeof (int));
+ cleanups = make_cleanup (xfree, offsets);
+
+ for (i = 0; i < op_end - op_ptr; ++i)
+ offsets[i] = -1;
+
+ make_cleanup (VEC_cleanup (int), &dw_labels);
+ make_cleanup (VEC_cleanup (int), &patches);
+
+ /* By default we are making an address. */
+ loc->kind = axs_lvalue_memory;
+
+ while (op_ptr < op_end)
+ {
+ enum dwarf_location_atom op = *op_ptr;
+ ULONGEST uoffset, reg;
+ LONGEST offset;
+ int i;
+
+ offsets[op_ptr - base] = expr->len;
+ ++op_ptr;
+
+ /* Our basic approach to code generation is to map DWARF
+ operations directly to AX operations. However, there are
+ some differences.
+
+ First, DWARF works on address-sized units, but AX always uses
+ LONGEST. For most operations we simply ignore this
+ difference; instead we generate sign extensions as needed
+ before division and comparison operations. It would be nice
+ to omit the sign extensions, but there is no way to determine
+ the size of the target's LONGEST. (This code uses the size
+ of the host LONGEST in some cases -- that is a bug but it is
+ difficult to fix.)
+
+ Second, some DWARF operations cannot be translated to AX.
+ For these we simply fail. See
+ http://sourceware.org/bugzilla/show_bug.cgi?id=11662. */
+ switch (op)
+ {
+ case DW_OP_lit0:
+ case DW_OP_lit1:
+ case DW_OP_lit2:
+ case DW_OP_lit3:
+ case DW_OP_lit4:
+ case DW_OP_lit5:
+ case DW_OP_lit6:
+ case DW_OP_lit7:
+ case DW_OP_lit8:
+ case DW_OP_lit9:
+ case DW_OP_lit10:
+ case DW_OP_lit11:
+ case DW_OP_lit12:
+ case DW_OP_lit13:
+ case DW_OP_lit14:
+ case DW_OP_lit15:
+ case DW_OP_lit16:
+ case DW_OP_lit17:
+ case DW_OP_lit18:
+ case DW_OP_lit19:
+ case DW_OP_lit20:
+ case DW_OP_lit21:
+ case DW_OP_lit22:
+ case DW_OP_lit23:
+ case DW_OP_lit24:
+ case DW_OP_lit25:
+ case DW_OP_lit26:
+ case DW_OP_lit27:
+ case DW_OP_lit28:
+ case DW_OP_lit29:
+ case DW_OP_lit30:
+ case DW_OP_lit31:
+ ax_const_l (expr, op - DW_OP_lit0);
+ break;
+
+ case DW_OP_addr:
+ uoffset = extract_unsigned_integer (op_ptr, addr_size, byte_order);
+ op_ptr += 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)
+ uoffset += dwarf2_per_cu_text_offset (per_cu);
+ ax_const_l (expr, uoffset);
+ break;
+
+ case DW_OP_const1u:
+ ax_const_l (expr, extract_unsigned_integer (op_ptr, 1, byte_order));
+ op_ptr += 1;
+ break;
+ case DW_OP_const1s:
+ ax_const_l (expr, extract_signed_integer (op_ptr, 1, byte_order));
+ op_ptr += 1;
+ break;
+ case DW_OP_const2u:
+ ax_const_l (expr, extract_unsigned_integer (op_ptr, 2, byte_order));
+ op_ptr += 2;
+ break;
+ case DW_OP_const2s:
+ ax_const_l (expr, extract_signed_integer (op_ptr, 2, byte_order));
+ op_ptr += 2;
+ break;
+ case DW_OP_const4u:
+ ax_const_l (expr, extract_unsigned_integer (op_ptr, 4, byte_order));
+ op_ptr += 4;
+ break;
+ case DW_OP_const4s:
+ ax_const_l (expr, extract_signed_integer (op_ptr, 4, byte_order));
+ op_ptr += 4;
+ break;
+ case DW_OP_const8u:
+ ax_const_l (expr, extract_unsigned_integer (op_ptr, 8, byte_order));
+ op_ptr += 8;
+ break;
+ case DW_OP_const8s:
+ ax_const_l (expr, extract_signed_integer (op_ptr, 8, byte_order));
+ op_ptr += 8;
+ break;
+ case DW_OP_constu:
+ op_ptr = read_uleb128 (op_ptr, op_end, &uoffset);
+ ax_const_l (expr, uoffset);
+ break;
+ case DW_OP_consts:
+ op_ptr = read_sleb128 (op_ptr, op_end, &offset);
+ ax_const_l (expr, offset);
+ break;
+
+ case DW_OP_reg0:
+ case DW_OP_reg1:
+ case DW_OP_reg2:
+ case DW_OP_reg3:
+ case DW_OP_reg4:
+ case DW_OP_reg5:
+ case DW_OP_reg6:
+ case DW_OP_reg7:
+ case DW_OP_reg8:
+ case DW_OP_reg9:
+ case DW_OP_reg10:
+ case DW_OP_reg11:
+ case DW_OP_reg12:
+ case DW_OP_reg13:
+ case DW_OP_reg14:
+ case DW_OP_reg15:
+ case DW_OP_reg16:
+ case DW_OP_reg17:
+ case DW_OP_reg18:
+ case DW_OP_reg19:
+ case DW_OP_reg20:
+ case DW_OP_reg21:
+ case DW_OP_reg22:
+ case DW_OP_reg23:
+ case DW_OP_reg24:
+ case DW_OP_reg25:
+ case DW_OP_reg26:
+ case DW_OP_reg27:
+ case DW_OP_reg28:
+ case DW_OP_reg29:
+ case DW_OP_reg30:
+ case DW_OP_reg31:
+ dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_regx");
+ loc->u.reg = translate_register (arch, op - DW_OP_reg0);
+ loc->kind = axs_lvalue_register;
+ break;
+
+ case DW_OP_regx:
+ op_ptr = read_uleb128 (op_ptr, op_end, ®);
+ dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_regx");
+ loc->u.reg = translate_register (arch, reg);
+ loc->kind = axs_lvalue_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."));
+ if (len > sizeof (ULONGEST))
+ error (_("Cannot translate DW_OP_implicit_value of %d bytes"),
+ (int) len);
+
+ ax_const_l (expr, extract_unsigned_integer (op_ptr, len,
+ byte_order));
+ op_ptr += len;
+ dwarf_expr_require_composition (op_ptr, op_end,
+ "DW_OP_implicit_value");
+
+ loc->kind = axs_rvalue;
+ }
+ break;
+
+ case DW_OP_stack_value:
+ dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_stack_value");
+ loc->kind = axs_rvalue;
+ break;
+
+ case DW_OP_breg0:
+ case DW_OP_breg1:
+ case DW_OP_breg2:
+ case DW_OP_breg3:
+ case DW_OP_breg4:
+ case DW_OP_breg5:
+ case DW_OP_breg6:
+ case DW_OP_breg7:
+ case DW_OP_breg8:
+ case DW_OP_breg9:
+ case DW_OP_breg10:
+ case DW_OP_breg11:
+ case DW_OP_breg12:
+ case DW_OP_breg13:
+ case DW_OP_breg14:
+ case DW_OP_breg15:
+ case DW_OP_breg16:
+ case DW_OP_breg17:
+ case DW_OP_breg18:
+ case DW_OP_breg19:
+ case DW_OP_breg20:
+ case DW_OP_breg21:
+ case DW_OP_breg22:
+ case DW_OP_breg23:
+ case DW_OP_breg24:
+ case DW_OP_breg25:
+ case DW_OP_breg26:
+ case DW_OP_breg27:
+ case DW_OP_breg28:
+ case DW_OP_breg29:
+ case DW_OP_breg30:
+ case DW_OP_breg31:
+ op_ptr = read_sleb128 (op_ptr, op_end, &offset);
+ i = translate_register (arch, op - DW_OP_breg0);
+ ax_reg (expr, i);
+ if (offset != 0)
+ {
+ ax_const_l (expr, offset);
+ ax_simple (expr, aop_add);
+ }
+ break;
+ case DW_OP_bregx:
+ {
+ op_ptr = read_uleb128 (op_ptr, op_end, ®);
+ op_ptr = read_sleb128 (op_ptr, op_end, &offset);
+ i = translate_register (arch, reg);
+ ax_reg (expr, i);
+ if (offset != 0)
+ {
+ ax_const_l (expr, offset);
+ ax_simple (expr, aop_add);
+ }
+ }
+ break;
+ case DW_OP_fbreg:
+ {
+ const gdb_byte *datastart;
+ size_t datalen;
+ unsigned int before_stack_len;
+ struct block *b;
+ struct symbol *framefunc;
+ LONGEST base_offset = 0;
+
+ b = block_for_pc (expr->scope);
+
+ if (!b)
+ error (_("No block found for address"));
+
+ framefunc = block_linkage_function (b);
+
+ if (!framefunc)
+ error (_("No function found for block"));
+
+ dwarf_expr_frame_base_1 (framefunc, expr->scope,
+ &datastart, &datalen);
+
+ op_ptr = read_sleb128 (op_ptr, op_end, &offset);
+ compile_dwarf_to_ax (expr, loc, arch, addr_size, datastart,
+ datastart + datalen, per_cu);
+
+ if (offset != 0)
+ {
+ ax_const_l (expr, offset);
+ ax_simple (expr, aop_add);
+ }
+
+ loc->kind = axs_lvalue_memory;
+ }
+ break;
+
+ case DW_OP_dup:
+ ax_simple (expr, aop_dup);
+ break;
+
+ case DW_OP_drop:
+ ax_simple (expr, aop_pop);
+ break;
+
+ case DW_OP_pick:
+ offset = *op_ptr++;
+ unimplemented (op);
+ break;
+
+ case DW_OP_swap:
+ ax_simple (expr, aop_swap);
+ break;
+
+ case DW_OP_over:
+ /* We can't directly support DW_OP_over, but GCC emits it as
+ part of a sequence to implement signed modulus. As a
+ hack, we recognize this sequence. Note that if GCC ever
+ generates a branch to the middle of this sequence, then
+ we will die somehow. */
+ if (op_end - op_ptr >= 4
+ && op_ptr[0] == DW_OP_over
+ && op_ptr[1] == DW_OP_div
+ && op_ptr[2] == DW_OP_mul
+ && op_ptr[3] == DW_OP_minus)
+ {
+ /* Sign extend the operands. */
+ ax_ext (expr, addr_size_bits);
+ ax_simple (expr, aop_swap);
+ ax_ext (expr, addr_size_bits);
+ ax_simple (expr, aop_swap);
+ ax_simple (expr, aop_rem_signed);
+ op_ptr += 4;
+ }
+ else
+ unimplemented (op);
+ break;
+
+ case DW_OP_rot:
+ unimplemented (op);
+ break;
+
+ case DW_OP_deref:
+ case DW_OP_deref_size:
+ {
+ int size;
+
+ if (op == DW_OP_deref_size)
+ size = *op_ptr++;
+ else
+ size = addr_size;
+
+ switch (size)
+ {
+ case 8:
+ ax_simple (expr, aop_ref8);
+ break;
+ case 16:
+ ax_simple (expr, aop_ref16);
+ break;
+ case 32:
+ ax_simple (expr, aop_ref32);
+ break;
+ case 64:
+ ax_simple (expr, aop_ref64);
+ break;
+ default:
+ error (_("Unsupported size %d in %s"),
+ size, dwarf_stack_op_name (op, 1));
+ }
+ }
+ break;
+
+ case DW_OP_abs:
+ /* Sign extend the operand. */
+ ax_ext (expr, addr_size_bits);
+ ax_simple (expr, aop_dup);
+ ax_const_l (expr, 0);
+ ax_simple (expr, aop_less_signed);
+ ax_simple (expr, aop_log_not);
+ i = ax_goto (expr, aop_if_goto);
+ /* We have to emit 0 - X. */
+ ax_const_l (expr, 0);
+ ax_simple (expr, aop_swap);
+ ax_simple (expr, aop_sub);
+ ax_label (expr, i, expr->len);
+ break;
+
+ case DW_OP_neg:
+ /* No need to sign extend here. */
+ ax_const_l (expr, 0);
+ ax_simple (expr, aop_swap);
+ ax_simple (expr, aop_sub);
+ break;
+
+ case DW_OP_not:
+ /* Sign extend the operand. */
+ ax_ext (expr, addr_size_bits);
+ ax_simple (expr, aop_bit_not);
+ break;
+
+ case DW_OP_plus_uconst:
+ op_ptr = read_uleb128 (op_ptr, op_end, ®);
+ /* It would be really weird to emit `DW_OP_plus_uconst 0',
+ but we micro-optimize anyhow. */
+ if (reg != 0)
+ {
+ ax_const_l (expr, reg);
+ ax_simple (expr, aop_add);
+ }
+ break;
+
+ case DW_OP_and:
+ ax_simple (expr, aop_bit_and);
+ break;
+
+ case DW_OP_div:
+ /* Sign extend the operands. */
+ ax_ext (expr, addr_size_bits);
+ ax_simple (expr, aop_swap);
+ ax_ext (expr, addr_size_bits);
+ ax_simple (expr, aop_swap);
+ ax_simple (expr, aop_div_signed);
+ break;
+
+ case DW_OP_minus:
+ ax_simple (expr, aop_sub);
+ break;
+
+ case DW_OP_mod:
+ ax_simple (expr, aop_rem_unsigned);
+ break;
+
+ case DW_OP_mul:
+ ax_simple (expr, aop_mul);
+ break;
+
+ case DW_OP_or:
+ ax_simple (expr, aop_bit_or);
+ break;
+
+ case DW_OP_plus:
+ ax_simple (expr, aop_add);
+ break;
+
+ case DW_OP_shl:
+ ax_simple (expr, aop_lsh);
+ break;
+
+ case DW_OP_shr:
+ ax_simple (expr, aop_rsh_unsigned);
+ break;
+
+ case DW_OP_shra:
+ ax_simple (expr, aop_rsh_signed);
+ break;
+
+ case DW_OP_xor:
+ ax_simple (expr, aop_bit_xor);
+ break;
+
+ case DW_OP_le:
+ /* Sign extend the operands. */
+ ax_ext (expr, addr_size_bits);
+ ax_simple (expr, aop_swap);
+ ax_ext (expr, addr_size_bits);
+ /* Note no swap here: A <= B is !(B < A). */
+ ax_simple (expr, aop_less_signed);
+ ax_simple (expr, aop_log_not);
+ break;
+
+ case DW_OP_ge:
+ /* Sign extend the operands. */
+ ax_ext (expr, addr_size_bits);
+ ax_simple (expr, aop_swap);
+ ax_ext (expr, addr_size_bits);
+ ax_simple (expr, aop_swap);
+ /* A >= B is !(A < B). */
+ ax_simple (expr, aop_less_signed);
+ ax_simple (expr, aop_log_not);
+ break;
+
+ case DW_OP_eq:
+ /* Sign extend the operands. */
+ ax_ext (expr, addr_size_bits);
+ ax_simple (expr, aop_swap);
+ ax_ext (expr, addr_size_bits);
+ /* No need for a second swap here. */
+ ax_simple (expr, aop_equal);
+ break;
+
+ case DW_OP_lt:
+ /* Sign extend the operands. */
+ ax_ext (expr, addr_size_bits);
+ ax_simple (expr, aop_swap);
+ ax_ext (expr, addr_size_bits);
+ ax_simple (expr, aop_swap);
+ ax_simple (expr, aop_less_signed);
+ break;
+
+ case DW_OP_gt:
+ /* Sign extend the operands. */
+ ax_ext (expr, addr_size_bits);
+ ax_simple (expr, aop_swap);
+ ax_ext (expr, addr_size_bits);
+ /* Note no swap here: A > B is B < A. */
+ ax_simple (expr, aop_less_signed);
+ break;
+
+ case DW_OP_ne:
+ /* Sign extend the operands. */
+ ax_ext (expr, addr_size_bits);
+ ax_simple (expr, aop_swap);
+ ax_ext (expr, addr_size_bits);
+ /* No need for a swap here. */
+ ax_simple (expr, aop_equal);
+ ax_simple (expr, aop_log_not);
+ break;
+
+ case DW_OP_call_frame_cfa:
+ unimplemented (op);
+ break;
+
+ case DW_OP_GNU_push_tls_address:
+ unimplemented (op);
+ break;
+
+ case DW_OP_skip:
+ offset = extract_signed_integer (op_ptr, 2, byte_order);
+ op_ptr += 2;
+ i = ax_goto (expr, aop_goto);
+ VEC_safe_push (int, dw_labels, op_ptr + offset - base);
+ VEC_safe_push (int, patches, i);
+ break;
+
+ case DW_OP_bra:
+ offset = extract_signed_integer (op_ptr, 2, byte_order);
+ op_ptr += 2;
+ /* Zero extend the operand. */
+ ax_zero_ext (expr, addr_size_bits);
+ i = ax_goto (expr, aop_if_goto);
+ VEC_safe_push (int, dw_labels, op_ptr + offset - base);
+ VEC_safe_push (int, patches, i);
+ break;
+
+ case DW_OP_nop:
+ break;
+
+ case DW_OP_piece:
+ case DW_OP_bit_piece:
+ {
+ ULONGEST size, offset;
+
+ if (op_ptr - 1 == previous_piece)
+ error (_("Cannot translate empty pieces to agent expressions"));
+ previous_piece = op_ptr - 1;
+
+ op_ptr = read_uleb128 (op_ptr, op_end, &size);
+ if (op == DW_OP_piece)
+ {
+ size *= 8;
+ offset = 0;
+ }
+ else
+ op_ptr = read_uleb128 (op_ptr, op_end, &offset);
+
+ if (bits_collected + size > 8 * sizeof (LONGEST))
+ error (_("Expression pieces exceed word size"));
+
+ /* Access the bits. */
+ switch (loc->kind)
+ {
+ case axs_lvalue_register:
+ ax_reg (expr, loc->u.reg);
+ break;
+
+ case axs_lvalue_memory:
+ /* Offset the pointer, if needed. */
+ if (offset > 8)
+ {
+ ax_const_l (expr, offset / 8);
+ ax_simple (expr, aop_add);
+ offset %= 8;
+ }
+ access_memory (arch, expr, size);
+ break;
+ }
+
+ /* For a bits-big-endian target, shift up what we already
+ have. For a bits-little-endian target, shift up the
+ new data. Note that there is a potential bug here if
+ the DWARF expression leaves multiple values on the
+ stack. */
+ if (bits_collected > 0)
+ {
+ if (bits_big_endian)
+ {
+ ax_simple (expr, aop_swap);
+ ax_const_l (expr, size);
+ ax_simple (expr, aop_lsh);
+ /* We don't need a second swap here, because
+ aop_bit_or is symmetric. */
+ }
+ else
+ {
+ ax_const_l (expr, size);
+ ax_simple (expr, aop_lsh);
+ }
+ ax_simple (expr, aop_bit_or);
+ }
+
+ bits_collected += size;
+ loc->kind = axs_rvalue;
+ }
+ break;
+
+ case DW_OP_GNU_uninit:
+ unimplemented (op);
+
+ case DW_OP_call2:
+ case DW_OP_call4:
+ {
+ struct dwarf2_locexpr_baton block;
+ int size = (op == DW_OP_call2 ? 2 : 4);
+
+ uoffset = extract_unsigned_integer (op_ptr, size, byte_order);
+ op_ptr += size;
+
+ block = dwarf2_fetch_die_location_block (uoffset, per_cu);
+
+ /* DW_OP_call_ref is currently not supported. */
+ gdb_assert (block.per_cu == per_cu);
+
+ compile_dwarf_to_ax (expr, loc, arch, addr_size,
+ block.data, block.data + block.size,
+ per_cu);
+ }
+ break;
+
+ case DW_OP_call_ref:
+ unimplemented (op);
+
+ default:
+ error (_("Unhandled dwarf expression opcode 0x%x"), op);
+ }
+ }
+
+ /* Patch all the branches we emitted. */
+ for (i = 0; i < VEC_length (int, patches); ++i)
+ {
+ int targ = offsets[VEC_index (int, dw_labels, i)];
+ if (targ == -1)
+ internal_error (__FILE__, __LINE__, _("invalid label"));
+ ax_label (expr, VEC_index (int, patches, i), targ);
+ }
+
+ do_cleanups (cleanups);
+}
+
+\f
+/* Return the value of SYMBOL in FRAME using the DWARF-2 expression
evaluator to calculate the location. */
static struct value *
locexpr_read_variable (struct symbol *symbol, struct frame_info *frame)
{
struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol);
struct value *val;
- val = dwarf2_evaluate_loc_desc (symbol, frame, dlbaton->data, dlbaton->size,
- dlbaton->objfile);
+
+ val = dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol), frame, dlbaton->data,
+ dlbaton->size, dlbaton->per_cu);
return val;
}
locexpr_read_needs_frame (struct symbol *symbol)
{
struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol);
- return dwarf2_loc_desc_needs_frame (dlbaton->data, dlbaton->size);
+
+ return dwarf2_loc_desc_needs_frame (dlbaton->data, dlbaton->size,
+ dlbaton->per_cu);
}
-/* Print a natural-language description of SYMBOL to STREAM. */
+/* Return true if DATA points to the end of a piece. END is one past
+ the last byte in the expression. */
+
static int
-locexpr_describe_location (struct symbol *symbol, struct ui_file *stream)
+piece_end_p (const gdb_byte *data, const gdb_byte *end)
{
- /* FIXME: be more extensive. */
- struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol);
+ return data == end || data[0] == DW_OP_piece || data[0] == DW_OP_bit_piece;
+}
+
+/* Nicely describe a single piece of a location, returning an updated
+ position in the bytecode sequence. This function cannot recognize
+ all locations; if a location is not recognized, it simply returns
+ DATA. */
+
+static const gdb_byte *
+locexpr_describe_location_piece (struct symbol *symbol, struct ui_file *stream,
+ CORE_ADDR addr, struct objfile *objfile,
+ const gdb_byte *data, const gdb_byte *end,
+ unsigned int addr_size)
+{
+ struct gdbarch *gdbarch = get_objfile_arch (objfile);
+ int regno;
+
+ if (data[0] >= DW_OP_reg0 && data[0] <= DW_OP_reg31)
+ {
+ regno = gdbarch_dwarf2_reg_to_regnum (gdbarch, data[0] - DW_OP_reg0);
+ fprintf_filtered (stream, _("a variable in $%s"),
+ gdbarch_register_name (gdbarch, regno));
+ data += 1;
+ }
+ else if (data[0] == DW_OP_regx)
+ {
+ ULONGEST reg;
+
+ data = read_uleb128 (data + 1, end, ®);
+ regno = gdbarch_dwarf2_reg_to_regnum (gdbarch, reg);
+ fprintf_filtered (stream, _("a variable in $%s"),
+ gdbarch_register_name (gdbarch, regno));
+ }
+ else if (data[0] == DW_OP_fbreg)
+ {
+ struct block *b;
+ struct symbol *framefunc;
+ int frame_reg = 0;
+ LONGEST frame_offset;
+ const gdb_byte *base_data, *new_data;
+ size_t base_size;
+ LONGEST base_offset = 0;
+
+ new_data = read_sleb128 (data + 1, end, &frame_offset);
+ if (!piece_end_p (new_data, end))
+ return data;
+ data = new_data;
+
+ b = block_for_pc (addr);
+
+ if (!b)
+ error (_("No block found for address for symbol \"%s\"."),
+ SYMBOL_PRINT_NAME (symbol));
+
+ framefunc = block_linkage_function (b);
+
+ if (!framefunc)
+ error (_("No function found for block for symbol \"%s\"."),
+ SYMBOL_PRINT_NAME (symbol));
- if (dlbaton->size == 1
- && dlbaton->data[0] >= DW_OP_reg0
- && dlbaton->data[0] <= DW_OP_reg31)
+ dwarf_expr_frame_base_1 (framefunc, addr, &base_data, &base_size);
+
+ if (base_data[0] >= DW_OP_breg0 && base_data[0] <= DW_OP_breg31)
+ {
+ const gdb_byte *buf_end;
+
+ frame_reg = base_data[0] - DW_OP_breg0;
+ buf_end = read_sleb128 (base_data + 1,
+ base_data + base_size, &base_offset);
+ if (buf_end != base_data + base_size)
+ error (_("Unexpected opcode after DW_OP_breg%u for symbol \"%s\"."),
+ frame_reg, SYMBOL_PRINT_NAME (symbol));
+ }
+ else if (base_data[0] >= DW_OP_reg0 && base_data[0] <= DW_OP_reg31)
+ {
+ /* The frame base is just the register, with no offset. */
+ frame_reg = base_data[0] - DW_OP_reg0;
+ base_offset = 0;
+ }
+ else
+ {
+ /* We don't know what to do with the frame base expression,
+ so we can't trace this variable; give up. */
+ error (_("Cannot describe location of symbol \"%s\"; "
+ "DWARF 2 encoding not handled, "
+ "first opcode in base data is 0x%x."),
+ SYMBOL_PRINT_NAME (symbol), base_data[0]);
+ }
+
+ regno = gdbarch_dwarf2_reg_to_regnum (gdbarch, frame_reg);
+
+ fprintf_filtered (stream, _("a variable at frame base reg $%s offset %s+%s"),
+ gdbarch_register_name (gdbarch, regno),
+ plongest (base_offset), plongest (frame_offset));
+ }
+ else if (data[0] >= DW_OP_breg0 && data[0] <= DW_OP_breg31
+ && piece_end_p (data, end))
{
- int regno = DWARF2_REG_TO_REGNUM (dlbaton->data[0] - DW_OP_reg0);
+ LONGEST offset;
+
+ regno = gdbarch_dwarf2_reg_to_regnum (gdbarch, data[0] - DW_OP_breg0);
+
+ data = read_sleb128 (data + 1, end, &offset);
+
fprintf_filtered (stream,
- "a variable in register %s", REGISTER_NAME (regno));
- return 1;
+ _("a variable at offset %s from base reg $%s"),
+ plongest (offset),
+ gdbarch_register_name (gdbarch, regno));
}
- fprintf_filtered (stream,
- "a variable with complex or multiple locations (DWARF2)");
- return 1;
+ /* The location expression for a TLS variable looks like this (on a
+ 64-bit LE machine):
+
+ DW_AT_location : 10 byte block: 3 4 0 0 0 0 0 0 0 e0
+ (DW_OP_addr: 4; DW_OP_GNU_push_tls_address)
+
+ 0x3 is the encoding for DW_OP_addr, which has an operand as long
+ as the size of an address on the target machine (here is 8
+ bytes). Note that more recent version of GCC emit DW_OP_const4u
+ or DW_OP_const8u, depending on address size, rather than
+ DW_OP_addr. 0xe0 is the encoding for
+ DW_OP_GNU_push_tls_address. The operand represents the offset at
+ which the variable is within the thread local storage. */
+
+ else if (data + 1 + addr_size < end
+ && (data[0] == DW_OP_addr
+ || (addr_size == 4 && data[0] == DW_OP_const4u)
+ || (addr_size == 8 && data[0] == DW_OP_const8u))
+ && data[1 + addr_size] == DW_OP_GNU_push_tls_address
+ && piece_end_p (data + 2 + addr_size, end))
+ {
+ ULONGEST offset;
+ offset = extract_unsigned_integer (data + 1, addr_size,
+ gdbarch_byte_order (gdbarch));
+
+ fprintf_filtered (stream,
+ _("a thread-local variable at offset 0x%s "
+ "in the thread-local storage for `%s'"),
+ phex_nz (offset, addr_size), objfile->name);
+
+ data += 1 + addr_size + 1;
+ }
+ else if (data[0] >= DW_OP_lit0
+ && data[0] <= DW_OP_lit31
+ && data + 1 < end
+ && data[1] == DW_OP_stack_value)
+ {
+ fprintf_filtered (stream, _("the constant %d"), data[0] - DW_OP_lit0);
+ data += 2;
+ }
+
+ return data;
+}
+
+/* Disassemble an expression, stopping at the end of a piece or at the
+ end of the expression. Returns a pointer to the next unread byte
+ in the input expression. If ALL is nonzero, then this function
+ will keep going until it reaches the end of the expression. */
+
+static const gdb_byte *
+disassemble_dwarf_expression (struct ui_file *stream,
+ struct gdbarch *arch, unsigned int addr_size,
+ int offset_size,
+ const gdb_byte *data, const gdb_byte *end,
+ int all)
+{
+ const gdb_byte *start = data;
+
+ fprintf_filtered (stream, _("a complex DWARF expression:\n"));
+
+ while (data < end
+ && (all
+ || (data[0] != DW_OP_piece && data[0] != DW_OP_bit_piece)))
+ {
+ enum dwarf_location_atom op = *data++;
+ ULONGEST ul;
+ LONGEST l;
+ const char *name;
+
+ name = dwarf_stack_op_name (op, 0);
+
+ if (!name)
+ error (_("Unrecognized DWARF opcode 0x%02x at %ld"),
+ op, (long) (data - start));
+ fprintf_filtered (stream, " % 4ld: %s", (long) (data - start), name);
+
+ switch (op)
+ {
+ case DW_OP_addr:
+ ul = extract_unsigned_integer (data, addr_size,
+ gdbarch_byte_order (arch));
+ data += addr_size;
+ fprintf_filtered (stream, " 0x%s", phex_nz (ul, addr_size));
+ break;
+
+ case DW_OP_const1u:
+ ul = extract_unsigned_integer (data, 1, gdbarch_byte_order (arch));
+ data += 1;
+ fprintf_filtered (stream, " %s", pulongest (ul));
+ break;
+ case DW_OP_const1s:
+ l = extract_signed_integer (data, 1, gdbarch_byte_order (arch));
+ data += 1;
+ fprintf_filtered (stream, " %s", plongest (l));
+ break;
+ case DW_OP_const2u:
+ ul = extract_unsigned_integer (data, 2, gdbarch_byte_order (arch));
+ data += 2;
+ fprintf_filtered (stream, " %s", pulongest (ul));
+ break;
+ case DW_OP_const2s:
+ l = extract_signed_integer (data, 2, gdbarch_byte_order (arch));
+ data += 2;
+ fprintf_filtered (stream, " %s", plongest (l));
+ break;
+ case DW_OP_const4u:
+ ul = extract_unsigned_integer (data, 4, gdbarch_byte_order (arch));
+ data += 4;
+ fprintf_filtered (stream, " %s", pulongest (ul));
+ break;
+ case DW_OP_const4s:
+ l = extract_signed_integer (data, 4, gdbarch_byte_order (arch));
+ data += 4;
+ fprintf_filtered (stream, " %s", plongest (l));
+ break;
+ case DW_OP_const8u:
+ ul = extract_unsigned_integer (data, 8, gdbarch_byte_order (arch));
+ data += 8;
+ fprintf_filtered (stream, " %s", pulongest (ul));
+ break;
+ case DW_OP_const8s:
+ l = extract_signed_integer (data, 8, gdbarch_byte_order (arch));
+ data += 8;
+ fprintf_filtered (stream, " %s", plongest (l));
+ break;
+ case DW_OP_constu:
+ data = read_uleb128 (data, end, &ul);
+ fprintf_filtered (stream, " %s", pulongest (ul));
+ break;
+ case DW_OP_consts:
+ data = read_sleb128 (data, end, &l);
+ fprintf_filtered (stream, " %s", plongest (l));
+ break;
+
+ case DW_OP_reg0:
+ case DW_OP_reg1:
+ case DW_OP_reg2:
+ case DW_OP_reg3:
+ case DW_OP_reg4:
+ case DW_OP_reg5:
+ case DW_OP_reg6:
+ case DW_OP_reg7:
+ case DW_OP_reg8:
+ case DW_OP_reg9:
+ case DW_OP_reg10:
+ case DW_OP_reg11:
+ case DW_OP_reg12:
+ case DW_OP_reg13:
+ case DW_OP_reg14:
+ case DW_OP_reg15:
+ case DW_OP_reg16:
+ case DW_OP_reg17:
+ case DW_OP_reg18:
+ case DW_OP_reg19:
+ case DW_OP_reg20:
+ case DW_OP_reg21:
+ case DW_OP_reg22:
+ case DW_OP_reg23:
+ case DW_OP_reg24:
+ case DW_OP_reg25:
+ case DW_OP_reg26:
+ case DW_OP_reg27:
+ case DW_OP_reg28:
+ case DW_OP_reg29:
+ case DW_OP_reg30:
+ case DW_OP_reg31:
+ fprintf_filtered (stream, " [$%s]",
+ gdbarch_register_name (arch, op - DW_OP_reg0));
+ break;
+
+ case DW_OP_regx:
+ data = read_uleb128 (data, end, &ul);
+ fprintf_filtered (stream, " %s [$%s]", pulongest (ul),
+ gdbarch_register_name (arch, (int) ul));
+ break;
+
+ case DW_OP_implicit_value:
+ data = read_uleb128 (data, end, &ul);
+ data += ul;
+ fprintf_filtered (stream, " %s", pulongest (ul));
+ break;
+
+ case DW_OP_breg0:
+ case DW_OP_breg1:
+ case DW_OP_breg2:
+ case DW_OP_breg3:
+ case DW_OP_breg4:
+ case DW_OP_breg5:
+ case DW_OP_breg6:
+ case DW_OP_breg7:
+ case DW_OP_breg8:
+ case DW_OP_breg9:
+ case DW_OP_breg10:
+ case DW_OP_breg11:
+ case DW_OP_breg12:
+ case DW_OP_breg13:
+ case DW_OP_breg14:
+ case DW_OP_breg15:
+ case DW_OP_breg16:
+ case DW_OP_breg17:
+ case DW_OP_breg18:
+ case DW_OP_breg19:
+ case DW_OP_breg20:
+ case DW_OP_breg21:
+ case DW_OP_breg22:
+ case DW_OP_breg23:
+ case DW_OP_breg24:
+ case DW_OP_breg25:
+ case DW_OP_breg26:
+ case DW_OP_breg27:
+ case DW_OP_breg28:
+ case DW_OP_breg29:
+ case DW_OP_breg30:
+ case DW_OP_breg31:
+ data = read_sleb128 (data, end, &ul);
+ fprintf_filtered (stream, " %s [$%s]", pulongest (ul),
+ gdbarch_register_name (arch, op - DW_OP_breg0));
+ break;
+
+ case DW_OP_bregx:
+ {
+ ULONGEST offset;
+
+ data = read_uleb128 (data, end, &ul);
+ data = read_sleb128 (data, end, &offset);
+ fprintf_filtered (stream, " register %s [$%s] offset %s",
+ pulongest (ul),
+ gdbarch_register_name (arch, (int) ul),
+ pulongest (offset));
+ }
+ break;
+
+ case DW_OP_fbreg:
+ data = read_sleb128 (data, end, &ul);
+ fprintf_filtered (stream, " %s", pulongest (ul));
+ break;
+
+ case DW_OP_xderef_size:
+ case DW_OP_deref_size:
+ case DW_OP_pick:
+ fprintf_filtered (stream, " %d", *data);
+ ++data;
+ break;
+
+ case DW_OP_plus_uconst:
+ data = read_uleb128 (data, end, &ul);
+ fprintf_filtered (stream, " %s", pulongest (ul));
+ break;
+
+ case DW_OP_skip:
+ l = extract_signed_integer (data, 2, gdbarch_byte_order (arch));
+ data += 2;
+ fprintf_filtered (stream, " to %ld",
+ (long) (data + l - start));
+ break;
+
+ case DW_OP_bra:
+ l = extract_signed_integer (data, 2, gdbarch_byte_order (arch));
+ data += 2;
+ fprintf_filtered (stream, " %ld",
+ (long) (data + l - start));
+ break;
+
+ case DW_OP_call2:
+ ul = extract_unsigned_integer (data, 2, gdbarch_byte_order (arch));
+ data += 2;
+ fprintf_filtered (stream, " offset %s", phex_nz (ul, 2));
+ break;
+
+ case DW_OP_call4:
+ ul = extract_unsigned_integer (data, 4, gdbarch_byte_order (arch));
+ data += 4;
+ fprintf_filtered (stream, " offset %s", phex_nz (ul, 4));
+ break;
+
+ case DW_OP_call_ref:
+ ul = extract_unsigned_integer (data, offset_size,
+ gdbarch_byte_order (arch));
+ data += offset_size;
+ fprintf_filtered (stream, " offset %s", phex_nz (ul, offset_size));
+ break;
+
+ case DW_OP_piece:
+ data = read_uleb128 (data, end, &ul);
+ fprintf_filtered (stream, " %s (bytes)", pulongest (ul));
+ break;
+
+ case DW_OP_bit_piece:
+ {
+ ULONGEST offset;
+
+ data = read_uleb128 (data, end, &ul);
+ data = read_uleb128 (data, end, &offset);
+ fprintf_filtered (stream, " size %s offset %s (bits)",
+ pulongest (ul), pulongest (offset));
+ }
+ break;
+ }
+
+ fprintf_filtered (stream, "\n");
+ }
+
+ return data;
+}
+
+/* Describe a single location, which may in turn consist of multiple
+ pieces. */
+
+static void
+locexpr_describe_location_1 (struct symbol *symbol, CORE_ADDR addr,
+ struct ui_file *stream,
+ const gdb_byte *data, int size,
+ struct objfile *objfile, unsigned int addr_size,
+ int offset_size)
+{
+ const gdb_byte *end = data + size;
+ int first_piece = 1, bad = 0;
+
+ while (data < end)
+ {
+ const gdb_byte *here = data;
+ int disassemble = 1;
+
+ if (first_piece)
+ first_piece = 0;
+ else
+ fprintf_filtered (stream, _(", and "));
+
+ if (!dwarf2_always_disassemble)
+ {
+ data = locexpr_describe_location_piece (symbol, stream, addr, objfile,
+ data, end, addr_size);
+ /* If we printed anything, or if we have an empty piece,
+ then don't disassemble. */
+ if (data != here
+ || data[0] == DW_OP_piece
+ || data[0] == DW_OP_bit_piece)
+ disassemble = 0;
+ }
+ if (disassemble)
+ data = disassemble_dwarf_expression (stream, get_objfile_arch (objfile),
+ addr_size, offset_size, data, end,
+ dwarf2_always_disassemble);
+
+ if (data < end)
+ {
+ int empty = data == here;
+
+ if (disassemble)
+ fprintf_filtered (stream, " ");
+ if (data[0] == DW_OP_piece)
+ {
+ ULONGEST bytes;
+
+ data = read_uleb128 (data + 1, end, &bytes);
+
+ if (empty)
+ fprintf_filtered (stream, _("an empty %s-byte piece"),
+ pulongest (bytes));
+ else
+ fprintf_filtered (stream, _(" [%s-byte piece]"),
+ pulongest (bytes));
+ }
+ else if (data[0] == DW_OP_bit_piece)
+ {
+ ULONGEST bits, offset;
+
+ data = read_uleb128 (data + 1, end, &bits);
+ data = read_uleb128 (data, end, &offset);
+
+ if (empty)
+ fprintf_filtered (stream,
+ _("an empty %s-bit piece"),
+ pulongest (bits));
+ else
+ fprintf_filtered (stream,
+ _(" [%s-bit piece, offset %s bits]"),
+ pulongest (bits), pulongest (offset));
+ }
+ else
+ {
+ bad = 1;
+ break;
+ }
+ }
+ }
+
+ if (bad || data > end)
+ error (_("Corrupted DWARF2 expression for \"%s\"."),
+ SYMBOL_PRINT_NAME (symbol));
+}
+
+/* Print a natural-language description of SYMBOL to STREAM. This
+ version is for a symbol with a single location. */
+
+static void
+locexpr_describe_location (struct symbol *symbol, CORE_ADDR addr,
+ struct ui_file *stream)
+{
+ struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol);
+ struct objfile *objfile = dwarf2_per_cu_objfile (dlbaton->per_cu);
+ unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu);
+ int offset_size = dwarf2_per_cu_offset_size (dlbaton->per_cu);
+
+ locexpr_describe_location_1 (symbol, addr, stream, dlbaton->data, dlbaton->size,
+ objfile, addr_size, offset_size);
+}
+
+/* Describe the location of SYMBOL as an agent value in VALUE, generating
+ any necessary bytecode in AX. */
+
+static void
+locexpr_tracepoint_var_ref (struct symbol *symbol, struct gdbarch *gdbarch,
+ struct agent_expr *ax, struct axs_value *value)
+{
+ struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol);
+ unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu);
+
+ if (dlbaton->data == NULL || dlbaton->size == 0)
+ value->optimized_out = 1;
+ else
+ compile_dwarf_to_ax (ax, value, gdbarch, addr_size,
+ dlbaton->data, dlbaton->data + dlbaton->size,
+ dlbaton->per_cu);
}
/* The set of location functions used with the DWARF-2 expression
evaluator. */
-struct location_funcs dwarf2_locexpr_funcs = {
+const struct symbol_computed_ops dwarf2_locexpr_funcs = {
locexpr_read_variable,
locexpr_read_needs_frame,
locexpr_describe_location,
- NULL
+ locexpr_tracepoint_var_ref
+};
+
+
+/* Wrapper functions for location lists. These generally find
+ the appropriate location expression and call something above. */
+
+/* Return the value of SYMBOL in FRAME using the DWARF-2 expression
+ evaluator to calculate the location. */
+static struct value *
+loclist_read_variable (struct symbol *symbol, struct frame_info *frame)
+{
+ struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol);
+ struct value *val;
+ const gdb_byte *data;
+ size_t size;
+
+ data = find_location_expression (dlbaton, &size,
+ frame ? get_frame_address_in_block (frame)
+ : 0);
+ if (data == NULL)
+ {
+ val = allocate_value (SYMBOL_TYPE (symbol));
+ VALUE_LVAL (val) = not_lval;
+ set_value_optimized_out (val, 1);
+ }
+ else
+ val = dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol), frame, data, size,
+ dlbaton->per_cu);
+
+ return val;
+}
+
+/* Return non-zero iff we need a frame to evaluate SYMBOL. */
+static int
+loclist_read_needs_frame (struct symbol *symbol)
+{
+ /* If there's a location list, then assume we need to have a frame
+ to choose the appropriate location expression. With tracking of
+ global variables this is not necessarily true, but such tracking
+ is disabled in GCC at the moment until we figure out how to
+ represent it. */
+
+ return 1;
+}
+
+/* Print a natural-language description of SYMBOL to STREAM. This
+ version applies when there is a list of different locations, each
+ with a specified address range. */
+
+static void
+loclist_describe_location (struct symbol *symbol, CORE_ADDR addr,
+ struct ui_file *stream)
+{
+ struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol);
+ CORE_ADDR low, high;
+ const gdb_byte *loc_ptr, *buf_end;
+ int length, first = 1;
+ struct objfile *objfile = dwarf2_per_cu_objfile (dlbaton->per_cu);
+ struct gdbarch *gdbarch = get_objfile_arch (objfile);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu);
+ int offset_size = dwarf2_per_cu_offset_size (dlbaton->per_cu);
+ int signed_addr_p = bfd_get_sign_extend_vma (objfile->obfd);
+ CORE_ADDR base_mask = ~(~(CORE_ADDR)1 << (addr_size * 8 - 1));
+ /* Adjust base_address for relocatable objects. */
+ CORE_ADDR base_offset = dwarf2_per_cu_text_offset (dlbaton->per_cu);
+ CORE_ADDR base_address = dlbaton->base_address + base_offset;
+
+ loc_ptr = dlbaton->data;
+ buf_end = dlbaton->data + dlbaton->size;
+
+ fprintf_filtered (stream, _("multi-location:\n"));
+
+ /* Iterate through locations until we run out. */
+ while (1)
+ {
+ if (buf_end - loc_ptr < 2 * addr_size)
+ error (_("Corrupted DWARF expression for symbol \"%s\"."),
+ SYMBOL_PRINT_NAME (symbol));
+
+ if (signed_addr_p)
+ low = extract_signed_integer (loc_ptr, addr_size, byte_order);
+ else
+ low = extract_unsigned_integer (loc_ptr, addr_size, byte_order);
+ loc_ptr += addr_size;
+
+ if (signed_addr_p)
+ high = extract_signed_integer (loc_ptr, addr_size, byte_order);
+ else
+ high = extract_unsigned_integer (loc_ptr, addr_size, byte_order);
+ loc_ptr += addr_size;
+
+ /* A base-address-selection entry. */
+ if ((low & base_mask) == base_mask)
+ {
+ base_address = high + base_offset;
+ fprintf_filtered (stream, _(" Base address %s"),
+ paddress (gdbarch, base_address));
+ continue;
+ }
+
+ /* An end-of-list entry. */
+ if (low == 0 && high == 0)
+ break;
+
+ /* Otherwise, a location expression entry. */
+ low += base_address;
+ high += base_address;
+
+ length = extract_unsigned_integer (loc_ptr, 2, byte_order);
+ loc_ptr += 2;
+
+ /* (It would improve readability to print only the minimum
+ necessary digits of the second number of the range.) */
+ fprintf_filtered (stream, _(" Range %s-%s: "),
+ paddress (gdbarch, low), paddress (gdbarch, high));
+
+ /* Now describe this particular location. */
+ locexpr_describe_location_1 (symbol, low, stream, loc_ptr, length,
+ objfile, addr_size, offset_size);
+
+ fprintf_filtered (stream, "\n");
+
+ loc_ptr += length;
+ }
+}
+
+/* Describe the location of SYMBOL as an agent value in VALUE, generating
+ any necessary bytecode in AX. */
+static void
+loclist_tracepoint_var_ref (struct symbol *symbol, struct gdbarch *gdbarch,
+ struct agent_expr *ax, struct axs_value *value)
+{
+ struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol);
+ const gdb_byte *data;
+ size_t size;
+ unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu);
+
+ data = find_location_expression (dlbaton, &size, ax->scope);
+ if (data == NULL || size == 0)
+ value->optimized_out = 1;
+ else
+ compile_dwarf_to_ax (ax, value, gdbarch, addr_size, data, data + size,
+ dlbaton->per_cu);
+}
+
+/* The set of location functions used with the DWARF-2 expression
+ evaluator and location lists. */
+const struct symbol_computed_ops dwarf2_loclist_funcs = {
+ loclist_read_variable,
+ loclist_read_needs_frame,
+ loclist_describe_location,
+ loclist_tracepoint_var_ref
};