-/* Dwarf2 Expression Evaluator
- Copyright 2001, 2002, 2003 Free Software Foundation, Inc.
+/* DWARF 2 Expression Evaluator.
+
+ Copyright (C) 2001-2015 Free Software Foundation, Inc.
+
Contributed by Daniel Berlin (dan@dberlin.org)
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
+ 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,
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 "symtab.h"
#include "gdbtypes.h"
#include "value.h"
#include "gdbcore.h"
-#include "elf/dwarf2.h"
+#include "dwarf2.h"
#include "dwarf2expr.h"
/* Local prototypes. */
static void execute_stack_op (struct dwarf_expr_context *,
- unsigned char *, unsigned char *);
+ const gdb_byte *, const gdb_byte *);
+
+/* Cookie for gdbarch data. */
+
+static struct gdbarch_data *dwarf_arch_cookie;
+
+/* This holds gdbarch-specific types used by the DWARF expression
+ evaluator. See comments in execute_stack_op. */
+
+struct dwarf_gdbarch_types
+{
+ struct type *dw_types[3];
+};
+
+/* Allocate and fill in dwarf_gdbarch_types for an arch. */
+
+static void *
+dwarf_gdbarch_types_init (struct gdbarch *gdbarch)
+{
+ struct dwarf_gdbarch_types *types
+ = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct dwarf_gdbarch_types);
+
+ /* The types themselves are lazily initialized. */
+
+ return types;
+}
+
+/* Return the type used for DWARF operations where the type is
+ unspecified in the DWARF spec. Only certain sizes are
+ supported. */
+
+static struct type *
+dwarf_expr_address_type (struct dwarf_expr_context *ctx)
+{
+ struct dwarf_gdbarch_types *types = gdbarch_data (ctx->gdbarch,
+ dwarf_arch_cookie);
+ int ndx;
+
+ if (ctx->addr_size == 2)
+ ndx = 0;
+ else if (ctx->addr_size == 4)
+ ndx = 1;
+ else if (ctx->addr_size == 8)
+ ndx = 2;
+ else
+ error (_("Unsupported address size in DWARF expressions: %d bits"),
+ 8 * ctx->addr_size);
+
+ if (types->dw_types[ndx] == NULL)
+ types->dw_types[ndx]
+ = arch_integer_type (ctx->gdbarch,
+ 8 * ctx->addr_size,
+ 0, "<signed DWARF address type>");
+
+ return types->dw_types[ndx];
+}
/* Create a new context for the expression evaluator. */
new_dwarf_expr_context (void)
{
struct dwarf_expr_context *retval;
- retval = xcalloc (1, sizeof (struct dwarf_expr_context));
- retval->stack_len = 10;
- retval->stack = xmalloc (10 * sizeof (CORE_ADDR));
+
+ retval = XCNEW (struct dwarf_expr_context);
+ retval->stack_len = 0;
+ retval->stack_allocated = 10;
+ retval->stack = XNEWVEC (struct dwarf_stack_value, retval->stack_allocated);
+ retval->num_pieces = 0;
+ retval->pieces = 0;
+ retval->max_recursion_depth = 0x100;
return retval;
}
free_dwarf_expr_context (struct dwarf_expr_context *ctx)
{
xfree (ctx->stack);
+ xfree (ctx->pieces);
xfree (ctx);
}
+/* Helper for make_cleanup_free_dwarf_expr_context. */
+
+static void
+free_dwarf_expr_context_cleanup (void *arg)
+{
+ free_dwarf_expr_context (arg);
+}
+
+/* Return a cleanup that calls free_dwarf_expr_context. */
+
+struct cleanup *
+make_cleanup_free_dwarf_expr_context (struct dwarf_expr_context *ctx)
+{
+ return make_cleanup (free_dwarf_expr_context_cleanup, ctx);
+}
+
/* Expand the memory allocated to CTX's stack to contain at least
NEED more elements than are currently used. */
{
if (ctx->stack_len + need > ctx->stack_allocated)
{
- size_t templen = ctx->stack_len * 2;
- while (templen < (ctx->stack_len + need))
- templen *= 2;
+ size_t newlen = ctx->stack_len + need + 10;
+
ctx->stack = xrealloc (ctx->stack,
- templen * sizeof (CORE_ADDR));
- ctx->stack_allocated = templen;
+ newlen * sizeof (struct dwarf_stack_value));
+ ctx->stack_allocated = newlen;
}
}
/* Push VALUE onto CTX's stack. */
-void
-dwarf_expr_push (struct dwarf_expr_context *ctx, CORE_ADDR value)
+static void
+dwarf_expr_push (struct dwarf_expr_context *ctx, struct value *value,
+ int in_stack_memory)
{
+ struct dwarf_stack_value *v;
+
dwarf_expr_grow_stack (ctx, 1);
- ctx->stack[ctx->stack_len++] = value;
+ v = &ctx->stack[ctx->stack_len++];
+ v->value = value;
+ v->in_stack_memory = in_stack_memory;
}
-/* Pop the top item off of CTX's stack. */
+/* Push VALUE onto CTX's stack. */
void
+dwarf_expr_push_address (struct dwarf_expr_context *ctx, CORE_ADDR value,
+ int in_stack_memory)
+{
+ dwarf_expr_push (ctx,
+ value_from_ulongest (dwarf_expr_address_type (ctx), value),
+ in_stack_memory);
+}
+
+/* Pop the top item off of CTX's stack. */
+
+static void
dwarf_expr_pop (struct dwarf_expr_context *ctx)
{
if (ctx->stack_len <= 0)
- error ("dwarf expression stack underflow");
+ error (_("dwarf expression stack underflow"));
ctx->stack_len--;
}
/* Retrieve the N'th item on CTX's stack. */
-CORE_ADDR
+struct value *
dwarf_expr_fetch (struct dwarf_expr_context *ctx, int n)
{
- if (ctx->stack_len < n)
- error ("Asked for position %d of stack, stack only has %d elements on it\n",
+ if (ctx->stack_len <= n)
+ error (_("Asked for position %d of stack, "
+ "stack only has %d elements on it."),
n, ctx->stack_len);
- return ctx->stack[ctx->stack_len - (1 + n)];
+ return ctx->stack[ctx->stack_len - (1 + n)].value;
+}
+
+/* Require that TYPE be an integral type; throw an exception if not. */
+
+static void
+dwarf_require_integral (struct type *type)
+{
+ if (TYPE_CODE (type) != TYPE_CODE_INT
+ && TYPE_CODE (type) != TYPE_CODE_CHAR
+ && TYPE_CODE (type) != TYPE_CODE_BOOL)
+ error (_("integral type expected in DWARF expression"));
+}
+
+/* Return the unsigned form of TYPE. TYPE is necessarily an integral
+ type. */
+
+static struct type *
+get_unsigned_type (struct gdbarch *gdbarch, struct type *type)
+{
+ switch (TYPE_LENGTH (type))
+ {
+ case 1:
+ return builtin_type (gdbarch)->builtin_uint8;
+ case 2:
+ return builtin_type (gdbarch)->builtin_uint16;
+ case 4:
+ return builtin_type (gdbarch)->builtin_uint32;
+ case 8:
+ return builtin_type (gdbarch)->builtin_uint64;
+ default:
+ error (_("no unsigned variant found for type, while evaluating "
+ "DWARF expression"));
+ }
+}
+
+/* Return the signed form of TYPE. TYPE is necessarily an integral
+ type. */
+
+static struct type *
+get_signed_type (struct gdbarch *gdbarch, struct type *type)
+{
+ switch (TYPE_LENGTH (type))
+ {
+ case 1:
+ return builtin_type (gdbarch)->builtin_int8;
+ case 2:
+ return builtin_type (gdbarch)->builtin_int16;
+ case 4:
+ return builtin_type (gdbarch)->builtin_int32;
+ case 8:
+ return builtin_type (gdbarch)->builtin_int64;
+ default:
+ error (_("no signed variant found for type, while evaluating "
+ "DWARF expression"));
+ }
+}
+
+/* Retrieve the N'th item on CTX's stack, converted to an address. */
+
+CORE_ADDR
+dwarf_expr_fetch_address (struct dwarf_expr_context *ctx, int n)
+{
+ struct value *result_val = dwarf_expr_fetch (ctx, n);
+ enum bfd_endian byte_order = gdbarch_byte_order (ctx->gdbarch);
+ ULONGEST result;
+
+ dwarf_require_integral (value_type (result_val));
+ result = extract_unsigned_integer (value_contents (result_val),
+ TYPE_LENGTH (value_type (result_val)),
+ byte_order);
+
+ /* For most architectures, calling extract_unsigned_integer() alone
+ is sufficient for extracting an address. However, some
+ architectures (e.g. MIPS) use signed addresses and using
+ extract_unsigned_integer() will not produce a correct
+ result. Make sure we invoke gdbarch_integer_to_address()
+ for those architectures which require it. */
+ if (gdbarch_integer_to_address_p (ctx->gdbarch))
+ {
+ gdb_byte *buf = alloca (ctx->addr_size);
+ struct type *int_type = get_unsigned_type (ctx->gdbarch,
+ value_type (result_val));
+
+ store_unsigned_integer (buf, ctx->addr_size, byte_order, result);
+ return gdbarch_integer_to_address (ctx->gdbarch, int_type, buf);
+ }
+
+ return (CORE_ADDR) result;
+}
+
+/* Retrieve the in_stack_memory flag of the N'th item on CTX's stack. */
+
+int
+dwarf_expr_fetch_in_stack_memory (struct dwarf_expr_context *ctx, int n)
+{
+ if (ctx->stack_len <= n)
+ error (_("Asked for position %d of stack, "
+ "stack only has %d elements on it."),
+ n, ctx->stack_len);
+ return ctx->stack[ctx->stack_len - (1 + n)].in_stack_memory;
+}
+
+/* Return true if the expression stack is empty. */
+
+static int
+dwarf_expr_stack_empty_p (struct dwarf_expr_context *ctx)
+{
+ return ctx->stack_len == 0;
+}
+/* Add a new piece to CTX's piece list. */
+static void
+add_piece (struct dwarf_expr_context *ctx, ULONGEST size, ULONGEST offset)
+{
+ struct dwarf_expr_piece *p;
+
+ ctx->num_pieces++;
+
+ ctx->pieces = xrealloc (ctx->pieces,
+ (ctx->num_pieces
+ * sizeof (struct dwarf_expr_piece)));
+
+ p = &ctx->pieces[ctx->num_pieces - 1];
+ p->location = ctx->location;
+ p->size = size;
+ p->offset = offset;
+
+ if (p->location == DWARF_VALUE_LITERAL)
+ {
+ p->v.literal.data = ctx->data;
+ p->v.literal.length = ctx->len;
+ }
+ else if (dwarf_expr_stack_empty_p (ctx))
+ {
+ p->location = DWARF_VALUE_OPTIMIZED_OUT;
+ /* Also reset the context's location, for our callers. This is
+ a somewhat strange approach, but this lets us avoid setting
+ the location to DWARF_VALUE_MEMORY in all the individual
+ cases in the evaluator. */
+ ctx->location = DWARF_VALUE_OPTIMIZED_OUT;
+ }
+ else if (p->location == DWARF_VALUE_MEMORY)
+ {
+ p->v.mem.addr = dwarf_expr_fetch_address (ctx, 0);
+ p->v.mem.in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 0);
+ }
+ else if (p->location == DWARF_VALUE_IMPLICIT_POINTER)
+ {
+ p->v.ptr.die.sect_off = ctx->len;
+ p->v.ptr.offset = value_as_long (dwarf_expr_fetch (ctx, 0));
+ }
+ else if (p->location == DWARF_VALUE_REGISTER)
+ p->v.regno = value_as_long (dwarf_expr_fetch (ctx, 0));
+ else
+ {
+ p->v.value = dwarf_expr_fetch (ctx, 0);
+ }
}
/* Evaluate the expression at ADDR (LEN bytes long) using the context
CTX. */
void
-dwarf_expr_eval (struct dwarf_expr_context *ctx, unsigned char *addr,
+dwarf_expr_eval (struct dwarf_expr_context *ctx, const gdb_byte *addr,
size_t len)
{
+ int old_recursion_depth = ctx->recursion_depth;
+
execute_stack_op (ctx, addr, addr + len);
+
+ /* CTX RECURSION_DEPTH becomes invalid if an exception was thrown here. */
+
+ gdb_assert (ctx->recursion_depth == old_recursion_depth);
}
-/* Decode the unsigned LEB128 constant at BUF into the variable pointed to
- by R, and return the new value of BUF. Verify that it doesn't extend
- past BUF_END. */
+/* Helper to read a uleb128 value or throw an error. */
-unsigned char *
-read_uleb128 (unsigned char *buf, unsigned char *buf_end, ULONGEST * r)
+const gdb_byte *
+safe_read_uleb128 (const gdb_byte *buf, const gdb_byte *buf_end,
+ uint64_t *r)
{
- unsigned shift = 0;
- ULONGEST result = 0;
- unsigned char byte;
+ 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;
+}
- while (1)
- {
- if (buf >= buf_end)
- error ("read_uleb128: Corrupted DWARF expression.");
+/* Helper to read a sleb128 value or throw an error. */
- byte = *buf++;
- result |= (byte & 0x7f) << shift;
- if ((byte & 0x80) == 0)
- break;
- shift += 7;
- }
- *r = result;
+const gdb_byte *
+safe_read_sleb128 (const gdb_byte *buf, const gdb_byte *buf_end,
+ int64_t *r)
+{
+ 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;
}
-/* 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. */
+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
+
+/* Check that the current operator is either at the end of an
+ expression, or that it is followed by a composition operator. */
-unsigned char *
-read_sleb128 (unsigned char *buf, unsigned char *buf_end, LONGEST * r)
+void
+dwarf_expr_require_composition (const gdb_byte *op_ptr, const gdb_byte *op_end,
+ const char *op_name)
{
- unsigned shift = 0;
- LONGEST result = 0;
- unsigned char byte;
+ /* It seems like DW_OP_GNU_uninit should be handled here. However,
+ it doesn't seem to make sense for DW_OP_*_value, and it was not
+ checked at the other place that this function is called. */
+ if (op_ptr != op_end && *op_ptr != DW_OP_piece && *op_ptr != DW_OP_bit_piece)
+ error (_("DWARF-2 expression error: `%s' operations must be "
+ "used either alone or in conjunction with DW_OP_piece "
+ "or DW_OP_bit_piece."),
+ op_name);
+}
- while (1)
- {
- if (buf >= buf_end)
- error ("read_sleb128: Corrupted DWARF expression.");
+/* Return true iff the types T1 and T2 are "the same". This only does
+ checks that might reasonably be needed to compare DWARF base
+ types. */
+
+static int
+base_types_equal_p (struct type *t1, struct type *t2)
+{
+ if (TYPE_CODE (t1) != TYPE_CODE (t2))
+ return 0;
+ if (TYPE_UNSIGNED (t1) != TYPE_UNSIGNED (t2))
+ return 0;
+ return TYPE_LENGTH (t1) == TYPE_LENGTH (t2);
+}
+
+/* A convenience function to call get_base_type on CTX and return the
+ result. DIE is the DIE whose type we need. SIZE is non-zero if
+ this function should verify that the resulting type has the correct
+ size. */
- byte = *buf++;
- result |= (byte & 0x7f) << shift;
- shift += 7;
- if ((byte & 0x80) == 0)
- break;
+static struct type *
+dwarf_get_base_type (struct dwarf_expr_context *ctx, cu_offset die, int size)
+{
+ struct type *result;
+
+ if (ctx->funcs->get_base_type)
+ {
+ result = ctx->funcs->get_base_type (ctx, die);
+ if (result == NULL)
+ error (_("Could not find type for DW_OP_GNU_const_type"));
+ if (size != 0 && TYPE_LENGTH (result) != size)
+ error (_("DW_OP_GNU_const_type has different sizes for type and data"));
}
- if (shift < (sizeof (*r) * 8) && (byte & 0x40) != 0)
- result |= -(1 << shift);
+ else
+ /* Anything will do. */
+ result = builtin_type (ctx->gdbarch)->builtin_int;
- *r = result;
- return buf;
+ return result;
}
-/* Read an address from BUF, and verify that it doesn't extend past
- BUF_END. The address is returned, and *BYTES_READ is set to the
- number of bytes read from BUF. */
+/* If <BUF..BUF_END] contains DW_FORM_block* with single DW_OP_reg* return the
+ DWARF register number. Otherwise return -1. */
-static CORE_ADDR
-read_address (unsigned char *buf, unsigned char *buf_end, int *bytes_read)
+int
+dwarf_block_to_dwarf_reg (const gdb_byte *buf, const gdb_byte *buf_end)
{
- CORE_ADDR result;
+ uint64_t dwarf_reg;
- if (buf_end - buf < TARGET_ADDR_BIT / TARGET_CHAR_BIT)
- error ("read_address: Corrupted DWARF expression.");
+ 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;
+ }
- *bytes_read = TARGET_ADDR_BIT / TARGET_CHAR_BIT;
- result = extract_address (buf, TARGET_ADDR_BIT / TARGET_CHAR_BIT);
- return result;
+ 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;
}
-/* Return the type of an address, for unsigned arithmetic. */
+/* 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. */
-static struct type *
-unsigned_address_type (void)
+int
+dwarf_block_to_dwarf_reg_deref (const gdb_byte *buf, const gdb_byte *buf_end,
+ CORE_ADDR *deref_size_return)
{
- switch (TARGET_ADDR_BIT / TARGET_CHAR_BIT)
+ uint64_t dwarf_reg;
+ int64_t offset;
+
+ if (buf_end <= buf)
+ return -1;
+
+ if (*buf >= DW_OP_breg0 && *buf <= DW_OP_breg31)
{
- case 2:
- return builtin_type_uint16;
- case 4:
- return builtin_type_uint32;
- case 8:
- return builtin_type_uint64;
- default:
- internal_error (__FILE__, __LINE__,
- "Unsupported address size.\n");
+ 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;
}
-/* Return the type of an address, for signed arithmetic. */
+/* 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. */
-static struct type *
-signed_address_type (void)
+int
+dwarf_block_to_fb_offset (const gdb_byte *buf, const gdb_byte *buf_end,
+ CORE_ADDR *fb_offset_return)
{
- switch (TARGET_ADDR_BIT / TARGET_CHAR_BIT)
+ 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)
{
- case 2:
- return builtin_type_int16;
- case 4:
- return builtin_type_int32;
- case 8:
- return builtin_type_int64;
- default:
- internal_error (__FILE__, __LINE__,
- "Unsupported address size.\n");
+ 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;
}
-\f
+
/* The engine for the expression evaluator. Using the context in CTX,
evaluate the expression between OP_PTR and OP_END. */
static void
-execute_stack_op (struct dwarf_expr_context *ctx, unsigned char *op_ptr,
- unsigned char *op_end)
+execute_stack_op (struct dwarf_expr_context *ctx,
+ const gdb_byte *op_ptr, const gdb_byte *op_end)
{
+ enum bfd_endian byte_order = gdbarch_byte_order (ctx->gdbarch);
+ /* Old-style "untyped" DWARF values need special treatment in a
+ couple of places, specifically DW_OP_mod and DW_OP_shr. We need
+ a special type for these values so we can distinguish them from
+ values that have an explicit type, because explicitly-typed
+ values do not need special treatment. This special type must be
+ different (in the `==' sense) from any base type coming from the
+ CU. */
+ struct type *address_type = dwarf_expr_address_type (ctx);
+
+ ctx->location = DWARF_VALUE_MEMORY;
+ ctx->initialized = 1; /* Default is initialized. */
+
+ if (ctx->recursion_depth > ctx->max_recursion_depth)
+ error (_("DWARF-2 expression error: Loop detected (%d)."),
+ ctx->recursion_depth);
+ ctx->recursion_depth++;
+
while (op_ptr < op_end)
{
- enum dwarf_location_atom op = *op_ptr++;
- CORE_ADDR result, memaddr;
- ULONGEST uoffset, reg;
- LONGEST offset;
- int bytes_read;
- enum lval_type expr_lval;
-
- ctx->in_reg = 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.
+ 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;
+ 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_lit30:
case DW_OP_lit31:
result = op - DW_OP_lit0;
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_addr:
- result = read_address (op_ptr, op_end, &bytes_read);
- op_ptr += bytes_read;
+ result = extract_unsigned_integer (op_ptr,
+ ctx->addr_size, byte_order);
+ op_ptr += ctx->addr_size;
+ /* Some versions of GCC emit DW_OP_addr before
+ DW_OP_GNU_push_tls_address. In this case the value is an
+ index, not an address. We don't support things like
+ branching between the address and the TLS op. */
+ if (op_ptr >= op_end || *op_ptr != DW_OP_GNU_push_tls_address)
+ result += ctx->offset;
+ result_val = value_from_ulongest (address_type, result);
+ break;
+
+ case DW_OP_GNU_addr_index:
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, &uoffset);
+ result = (ctx->funcs->get_addr_index) (ctx->baton, uoffset);
+ result += ctx->offset;
+ result_val = value_from_ulongest (address_type, result);
+ break;
+ case DW_OP_GNU_const_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);
+ result = extract_unsigned_integer (op_ptr, 1, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 1;
break;
case DW_OP_const1s:
- result = extract_signed_integer (op_ptr, 1);
+ result = extract_signed_integer (op_ptr, 1, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 1;
break;
case DW_OP_const2u:
- result = extract_unsigned_integer (op_ptr, 2);
+ result = extract_unsigned_integer (op_ptr, 2, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 2;
break;
case DW_OP_const2s:
- result = extract_signed_integer (op_ptr, 2);
+ result = extract_signed_integer (op_ptr, 2, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 2;
break;
case DW_OP_const4u:
- result = extract_unsigned_integer (op_ptr, 4);
+ result = extract_unsigned_integer (op_ptr, 4, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 4;
break;
case DW_OP_const4s:
- result = extract_signed_integer (op_ptr, 4);
+ result = extract_signed_integer (op_ptr, 4, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 4;
break;
case DW_OP_const8u:
- result = extract_unsigned_integer (op_ptr, 8);
+ result = extract_unsigned_integer (op_ptr, 8, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 8;
break;
case DW_OP_const8s:
- result = extract_signed_integer (op_ptr, 8);
+ result = extract_signed_integer (op_ptr, 8, byte_order);
+ result_val = value_from_ulongest (address_type, result);
op_ptr += 8;
break;
case DW_OP_constu:
- op_ptr = read_uleb128 (op_ptr, op_end, &uoffset);
+ 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;
/* The DW_OP_reg operations are required to occur alone in
case DW_OP_reg29:
case DW_OP_reg30:
case DW_OP_reg31:
- /* NOTE: in the presence of DW_OP_piece this check is incorrect. */
- if (op_ptr != op_end)
- error ("DWARF-2 expression error: DW_OP_reg operations must be "
- "used alone.");
-
- /* FIXME drow/2003-02-21: This call to read_reg could be pushed
- into the evaluator's caller by changing the semantics for in_reg.
- Then we wouldn't need to return an lval_type and a memaddr. */
- result = (ctx->read_reg) (ctx->baton, op - DW_OP_reg0, &expr_lval,
- &memaddr);
-
- if (expr_lval == lval_register)
- {
- ctx->regnum = op - DW_OP_reg0;
- ctx->in_reg = 1;
- }
- else
- result = memaddr;
-
+ if (op_ptr != op_end
+ && *op_ptr != DW_OP_piece
+ && *op_ptr != DW_OP_bit_piece
+ && *op_ptr != DW_OP_GNU_uninit)
+ error (_("DWARF-2 expression error: DW_OP_reg operations must be "
+ "used either alone or in conjunction with DW_OP_piece "
+ "or DW_OP_bit_piece."));
+
+ result = op - DW_OP_reg0;
+ result_val = value_from_ulongest (address_type, result);
+ ctx->location = DWARF_VALUE_REGISTER;
break;
case DW_OP_regx:
- op_ptr = read_uleb128 (op_ptr, op_end, ®);
- if (op_ptr != op_end)
- error ("DWARF-2 expression error: DW_OP_reg operations must be "
- "used alone.");
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, ®);
+ dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_regx");
+
+ result = reg;
+ result_val = value_from_ulongest (address_type, result);
+ ctx->location = DWARF_VALUE_REGISTER;
+ break;
+
+ case DW_OP_implicit_value:
+ {
+ uint64_t 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;
+ ctx->data = op_ptr;
+ ctx->location = DWARF_VALUE_LITERAL;
+ op_ptr += len;
+ dwarf_expr_require_composition (op_ptr, op_end,
+ "DW_OP_implicit_value");
+ }
+ goto no_push;
+
+ case DW_OP_stack_value:
+ ctx->location = DWARF_VALUE_STACK;
+ dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_stack_value");
+ goto no_push;
+
+ case DW_OP_GNU_implicit_pointer:
+ {
+ int64_t len;
- result = (ctx->read_reg) (ctx->baton, reg, &expr_lval, &memaddr);
+ if (ctx->ref_addr_size == -1)
+ error (_("DWARF-2 expression error: DW_OP_GNU_implicit_pointer "
+ "is not allowed in frame context"));
- if (expr_lval == lval_register)
- {
- ctx->regnum = reg;
- ctx->in_reg = 1;
- }
- else
- result = memaddr;
+ /* The referred-to DIE of sect_offset kind. */
+ ctx->len = extract_unsigned_integer (op_ptr, ctx->ref_addr_size,
+ byte_order);
+ op_ptr += ctx->ref_addr_size;
+ /* The byte offset into the data. */
+ op_ptr = safe_read_sleb128 (op_ptr, op_end, &len);
+ result = (ULONGEST) len;
+ result_val = value_from_ulongest (address_type, result);
+
+ ctx->location = DWARF_VALUE_IMPLICIT_POINTER;
+ dwarf_expr_require_composition (op_ptr, op_end,
+ "DW_OP_GNU_implicit_pointer");
+ }
break;
case DW_OP_breg0:
case DW_OP_breg30:
case DW_OP_breg31:
{
- op_ptr = read_sleb128 (op_ptr, op_end, &offset);
- result = (ctx->read_reg) (ctx->baton, op - DW_OP_breg0,
- &expr_lval, &memaddr);
+ op_ptr = safe_read_sleb128 (op_ptr, op_end, &offset);
+ result = (ctx->funcs->read_addr_from_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, &expr_lval, &memaddr);
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, ®);
+ op_ptr = safe_read_sleb128 (op_ptr, op_end, &offset);
+ result = (ctx->funcs->read_addr_from_reg) (ctx->baton, reg);
result += offset;
+ result_val = value_from_ulongest (address_type, result);
}
break;
case DW_OP_fbreg:
{
- unsigned char *datastart;
+ const gdb_byte *datastart;
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);
- result = dwarf_expr_fetch (ctx, 0);
- if (! ctx->in_reg)
- {
- char *buf = alloca (TARGET_ADDR_BIT / TARGET_CHAR_BIT);
- int bytes_read;
-
- (ctx->read_mem) (ctx->baton, buf, result,
- TARGET_ADDR_BIT / TARGET_CHAR_BIT);
- result = read_address (buf,
- buf + TARGET_ADDR_BIT / TARGET_CHAR_BIT,
- &bytes_read);
- }
+ if (ctx->location == DWARF_VALUE_MEMORY)
+ result = dwarf_expr_fetch_address (ctx, 0);
+ else if (ctx->location == DWARF_VALUE_REGISTER)
+ result = (ctx->funcs->read_addr_from_reg)
+ (ctx->baton,
+ value_as_long (dwarf_expr_fetch (ctx, 0)));
+ else
+ error (_("Not implemented: computing frame "
+ "base using explicit value operator"));
result = result + offset;
+ result_val = value_from_ulongest (address_type, result);
+ in_stack_memory = 1;
ctx->stack_len = before_stack_len;
- ctx->in_reg = 0;
+ ctx->location = DWARF_VALUE_MEMORY;
}
break;
+
case DW_OP_dup:
- result = dwarf_expr_fetch (ctx, 0);
+ result_val = dwarf_expr_fetch (ctx, 0);
+ in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 0);
break;
case DW_OP_drop:
case DW_OP_pick:
offset = *op_ptr++;
- result = dwarf_expr_fetch (ctx, offset);
+ result_val = dwarf_expr_fetch (ctx, offset);
+ in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, offset);
break;
+
+ case DW_OP_swap:
+ {
+ struct dwarf_stack_value t1, t2;
+
+ if (ctx->stack_len < 2)
+ error (_("Not enough elements for "
+ "DW_OP_swap. Need 2, have %d."),
+ ctx->stack_len);
+ t1 = ctx->stack[ctx->stack_len - 1];
+ t2 = ctx->stack[ctx->stack_len - 2];
+ ctx->stack[ctx->stack_len - 1] = t2;
+ ctx->stack[ctx->stack_len - 2] = t1;
+ goto no_push;
+ }
case DW_OP_over:
- result = dwarf_expr_fetch (ctx, 1);
+ result_val = dwarf_expr_fetch (ctx, 1);
+ in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 1);
break;
case DW_OP_rot:
{
- CORE_ADDR t1, t2, t3;
+ struct dwarf_stack_value t1, t2, t3;
if (ctx->stack_len < 3)
- error ("Not enough elements for DW_OP_rot. Need 3, have %d\n",
+ error (_("Not enough elements for "
+ "DW_OP_rot. Need 3, have %d."),
ctx->stack_len);
t1 = ctx->stack[ctx->stack_len - 1];
t2 = ctx->stack[ctx->stack_len - 2];
case DW_OP_deref:
case DW_OP_deref_size:
- case DW_OP_abs:
- case DW_OP_neg:
- case DW_OP_not:
- case DW_OP_plus_uconst:
- /* Unary operations. */
- result = dwarf_expr_fetch (ctx, 0);
- dwarf_expr_pop (ctx);
+ case DW_OP_GNU_deref_type:
+ {
+ int addr_size = (op == DW_OP_deref ? ctx->addr_size : *op_ptr++);
+ gdb_byte *buf = alloca (addr_size);
+ CORE_ADDR addr = dwarf_expr_fetch_address (ctx, 0);
+ struct type *type;
- switch (op)
- {
- case DW_OP_deref:
+ dwarf_expr_pop (ctx);
+
+ if (op == DW_OP_GNU_deref_type)
{
- char *buf = alloca (TARGET_ADDR_BIT / TARGET_CHAR_BIT);
- int bytes_read;
-
- (ctx->read_mem) (ctx->baton, buf, result,
- TARGET_ADDR_BIT / TARGET_CHAR_BIT);
- result = read_address (buf,
- buf + TARGET_ADDR_BIT / TARGET_CHAR_BIT,
- &bytes_read);
+ cu_offset 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);
}
- break;
+ else
+ type = address_type;
- case DW_OP_deref_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. */
+ if (TYPE_LENGTH (type) != addr_size)
{
- char *buf = alloca (TARGET_ADDR_BIT / TARGET_CHAR_BIT);
- int bytes_read;
+ ULONGEST result =
+ extract_unsigned_integer (buf, addr_size, byte_order);
+
+ buf = alloca (TYPE_LENGTH (type));
+ store_unsigned_integer (buf, TYPE_LENGTH (type),
+ byte_order, result);
+ }
+
+ result_val = value_from_contents_and_address (type, buf, addr);
+ break;
+ }
+
+ case DW_OP_abs:
+ case DW_OP_neg:
+ case DW_OP_not:
+ case DW_OP_plus_uconst:
+ {
+ /* Unary operations. */
+ result_val = dwarf_expr_fetch (ctx, 0);
+ dwarf_expr_pop (ctx);
- (ctx->read_mem) (ctx->baton, buf, result, *op_ptr++);
- result = read_address (buf,
- buf + TARGET_ADDR_BIT / TARGET_CHAR_BIT,
- &bytes_read);
+ switch (op)
+ {
+ case DW_OP_abs:
+ if (value_less (result_val,
+ value_zero (value_type (result_val), not_lval)))
+ result_val = value_neg (result_val);
+ break;
+ case DW_OP_neg:
+ result_val = value_neg (result_val);
+ break;
+ case DW_OP_not:
+ dwarf_require_integral (value_type (result_val));
+ result_val = value_complement (result_val);
+ break;
+ case DW_OP_plus_uconst:
+ dwarf_require_integral (value_type (result_val));
+ result = value_as_long (result_val);
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, ®);
+ result += reg;
+ result_val = value_from_ulongest (address_type, result);
+ break;
}
- break;
-
- case DW_OP_abs:
- if ((signed int) result < 0)
- result = -result;
- break;
- case DW_OP_neg:
- result = -result;
- break;
- case DW_OP_not:
- result = ~result;
- break;
- case DW_OP_plus_uconst:
- op_ptr = read_uleb128 (op_ptr, op_end, ®);
- result += reg;
- break;
- }
+ }
break;
case DW_OP_and:
case DW_OP_gt:
case DW_OP_ne:
{
- /* Binary operations. Use the value engine to do computations in
- the right width. */
- CORE_ADDR first, second;
- enum exp_opcode binop;
- struct value *val1, *val2;
+ /* Binary operations. */
+ struct value *first, *second;
second = dwarf_expr_fetch (ctx, 0);
dwarf_expr_pop (ctx);
- first = dwarf_expr_fetch (ctx, 1);
+ first = dwarf_expr_fetch (ctx, 0);
dwarf_expr_pop (ctx);
- val1 = value_from_longest (unsigned_address_type (), first);
- val2 = value_from_longest (unsigned_address_type (), second);
+ if (! base_types_equal_p (value_type (first), value_type (second)))
+ error (_("Incompatible types on DWARF stack"));
switch (op)
{
case DW_OP_and:
- binop = BINOP_BITWISE_AND;
+ dwarf_require_integral (value_type (first));
+ dwarf_require_integral (value_type (second));
+ result_val = value_binop (first, second, BINOP_BITWISE_AND);
break;
case DW_OP_div:
- binop = BINOP_DIV;
+ result_val = value_binop (first, second, BINOP_DIV);
+ break;
case DW_OP_minus:
- binop = BINOP_SUB;
+ result_val = value_binop (first, second, BINOP_SUB);
break;
case DW_OP_mod:
- binop = BINOP_MOD;
+ {
+ int cast_back = 0;
+ struct type *orig_type = value_type (first);
+
+ /* We have to special-case "old-style" untyped values
+ -- these must have mod computed using unsigned
+ math. */
+ if (orig_type == address_type)
+ {
+ struct type *utype
+ = get_unsigned_type (ctx->gdbarch, orig_type);
+
+ cast_back = 1;
+ first = value_cast (utype, first);
+ second = value_cast (utype, second);
+ }
+ /* Note that value_binop doesn't handle float or
+ decimal float here. This seems unimportant. */
+ result_val = value_binop (first, second, BINOP_MOD);
+ if (cast_back)
+ result_val = value_cast (orig_type, result_val);
+ }
break;
case DW_OP_mul:
- binop = BINOP_MUL;
+ result_val = value_binop (first, second, BINOP_MUL);
break;
case DW_OP_or:
- binop = BINOP_BITWISE_IOR;
+ dwarf_require_integral (value_type (first));
+ dwarf_require_integral (value_type (second));
+ result_val = value_binop (first, second, BINOP_BITWISE_IOR);
break;
case DW_OP_plus:
- binop = BINOP_ADD;
+ result_val = value_binop (first, second, BINOP_ADD);
break;
case DW_OP_shl:
- binop = BINOP_LSH;
+ dwarf_require_integral (value_type (first));
+ dwarf_require_integral (value_type (second));
+ result_val = value_binop (first, second, BINOP_LSH);
break;
case DW_OP_shr:
- binop = BINOP_RSH;
+ dwarf_require_integral (value_type (first));
+ dwarf_require_integral (value_type (second));
+ if (!TYPE_UNSIGNED (value_type (first)))
+ {
+ struct type *utype
+ = get_unsigned_type (ctx->gdbarch, value_type (first));
+
+ first = value_cast (utype, first);
+ }
+
+ result_val = value_binop (first, second, BINOP_RSH);
+ /* Make sure we wind up with the same type we started
+ with. */
+ if (value_type (result_val) != value_type (second))
+ result_val = value_cast (value_type (second), result_val);
+ break;
case DW_OP_shra:
- binop = BINOP_RSH;
- val1 = value_from_longest (signed_address_type (), first);
+ dwarf_require_integral (value_type (first));
+ dwarf_require_integral (value_type (second));
+ if (TYPE_UNSIGNED (value_type (first)))
+ {
+ struct type *stype
+ = get_signed_type (ctx->gdbarch, value_type (first));
+
+ first = value_cast (stype, first);
+ }
+
+ result_val = value_binop (first, second, BINOP_RSH);
+ /* Make sure we wind up with the same type we started
+ with. */
+ if (value_type (result_val) != value_type (second))
+ result_val = value_cast (value_type (second), result_val);
break;
case DW_OP_xor:
- binop = BINOP_BITWISE_XOR;
+ dwarf_require_integral (value_type (first));
+ dwarf_require_integral (value_type (second));
+ result_val = value_binop (first, second, BINOP_BITWISE_XOR);
break;
case DW_OP_le:
- binop = BINOP_LEQ;
+ /* A <= B is !(B < A). */
+ result = ! value_less (second, first);
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_ge:
- binop = BINOP_GEQ;
+ /* A >= B is !(A < B). */
+ result = ! value_less (first, second);
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_eq:
- binop = BINOP_EQUAL;
+ result = value_equal (first, second);
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_lt:
- binop = BINOP_LESS;
+ result = value_less (first, second);
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_gt:
- binop = BINOP_GTR;
+ /* A > B is B < A. */
+ result = value_less (second, first);
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_ne:
- binop = BINOP_NOTEQUAL;
+ result = ! value_equal (first, second);
+ result_val = value_from_ulongest (address_type, result);
break;
default:
internal_error (__FILE__, __LINE__,
- "Can't be reached.");
+ _("Can't be reached."));
}
- result = value_as_long (value_binop (val1, val2, binop));
}
break;
+ case DW_OP_call_frame_cfa:
+ result = (ctx->funcs->get_frame_cfa) (ctx->baton);
+ result_val = value_from_ulongest (address_type, result);
+ in_stack_memory = 1;
+ break;
+
case DW_OP_GNU_push_tls_address:
- result = dwarf_expr_fetch (ctx, 0);
+ /* Variable is at a constant offset in the thread-local
+ storage block into the objfile for the current thread and
+ the dynamic linker module containing this expression. Here
+ we return returns the offset from that base. The top of the
+ stack has the offset from the beginning of the thread
+ control block at which the variable is located. Nothing
+ should follow this operator, so the top of stack would be
+ returned. */
+ result = value_as_long (dwarf_expr_fetch (ctx, 0));
dwarf_expr_pop (ctx);
- result = (ctx->get_tls_address) (ctx->baton, result);
+ result = (ctx->funcs->get_tls_address) (ctx->baton, result);
+ result_val = value_from_ulongest (address_type, result);
break;
case DW_OP_skip:
- offset = extract_signed_integer (op_ptr, 2);
+ offset = extract_signed_integer (op_ptr, 2, byte_order);
op_ptr += 2;
op_ptr += offset;
goto no_push;
case DW_OP_bra:
- offset = extract_signed_integer (op_ptr, 2);
- op_ptr += 2;
- if (dwarf_expr_fetch (ctx, 0) != 0)
- op_ptr += offset;
- dwarf_expr_pop (ctx);
+ {
+ struct value *val;
+
+ offset = extract_signed_integer (op_ptr, 2, byte_order);
+ op_ptr += 2;
+ val = dwarf_expr_fetch (ctx, 0);
+ dwarf_require_integral (value_type (val));
+ if (value_as_long (val) != 0)
+ op_ptr += offset;
+ dwarf_expr_pop (ctx);
+ }
goto no_push;
case DW_OP_nop:
goto no_push;
+ case DW_OP_piece:
+ {
+ uint64_t size;
+
+ /* Record the piece. */
+ 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
+ type. */
+ if (ctx->location != DWARF_VALUE_LITERAL
+ && ctx->location != DWARF_VALUE_OPTIMIZED_OUT)
+ dwarf_expr_pop (ctx);
+ ctx->location = DWARF_VALUE_MEMORY;
+ }
+ goto no_push;
+
+ case DW_OP_bit_piece:
+ {
+ uint64_t size, 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 (ctx, size, offset);
+
+ /* Pop off the address/regnum, and reset the location
+ type. */
+ if (ctx->location != DWARF_VALUE_LITERAL
+ && ctx->location != DWARF_VALUE_OPTIMIZED_OUT)
+ dwarf_expr_pop (ctx);
+ ctx->location = DWARF_VALUE_MEMORY;
+ }
+ goto no_push;
+
+ case DW_OP_GNU_uninit:
+ if (op_ptr != op_end)
+ error (_("DWARF-2 expression error: DW_OP_GNU_uninit must always "
+ "be the very last op."));
+
+ ctx->initialized = 0;
+ goto no_push;
+
+ case DW_OP_call2:
+ {
+ 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:
+ {
+ 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:
+ {
+ 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:
+ {
+ cu_offset type_die;
+ int n;
+ const gdb_byte *data;
+ struct type *type;
+
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, &uoffset);
+ type_die.cu_off = uoffset;
+ n = *op_ptr++;
+ data = op_ptr;
+ op_ptr += n;
+
+ type = dwarf_get_base_type (ctx, type_die, n);
+ result_val = value_from_contents (type, data);
+ }
+ break;
+
+ case DW_OP_GNU_regval_type:
+ {
+ cu_offset type_die;
+ struct type *type;
+
+ 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_val = ctx->funcs->get_reg_value (ctx->baton, type, reg);
+ }
+ break;
+
+ case DW_OP_GNU_convert:
+ case DW_OP_GNU_reinterpret:
+ {
+ cu_offset type_die;
+ struct type *type;
+
+ op_ptr = safe_read_uleb128 (op_ptr, op_end, &uoffset);
+ type_die.cu_off = uoffset;
+
+ 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);
+
+ if (op == DW_OP_GNU_convert)
+ result_val = value_cast (type, result_val);
+ else if (type == value_type (result_val))
+ {
+ /* Nothing. */
+ }
+ else if (TYPE_LENGTH (type)
+ != TYPE_LENGTH (value_type (result_val)))
+ error (_("DW_OP_GNU_reinterpret has wrong size"));
+ else
+ result_val
+ = value_from_contents (type,
+ value_contents_all (result_val));
+ }
+ break;
+
+ case DW_OP_push_object_address:
+ /* Return the address of the object we are currently observing. */
+ result = (ctx->funcs->get_object_address) (ctx->baton);
+ result_val = value_from_ulongest (address_type, result);
+ break;
+
default:
- error ("Unhandled dwarf expression opcode");
+ error (_("Unhandled dwarf expression opcode 0x%x"), op);
}
/* Most things push a result value. */
- dwarf_expr_push (ctx, result);
- no_push:;
+ gdb_assert (result_val != NULL);
+ dwarf_expr_push (ctx, result_val, in_stack_memory);
+ no_push:
+ ;
}
+
+ /* To simplify our main caller, if the result is an implicit
+ pointer, then make a pieced value. This is ok because we can't
+ have implicit pointers in contexts where pieces are invalid. */
+ if (ctx->location == DWARF_VALUE_IMPLICIT_POINTER)
+ add_piece (ctx, 8 * ctx->addr_size, 0);
+
+abort_expression:
+ ctx->recursion_depth--;
+ gdb_assert (ctx->recursion_depth >= 0);
+}
+
+/* Stub dwarf_expr_context_funcs.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)
+{
+ dwarf_arch_cookie
+ = gdbarch_data_register_post_init (dwarf_gdbarch_types_init);
}