dd90784ccd
* dwarf2expr.c (execute_stack_op): Handle DW_OP_GNU_entry_value. New label abort_expression. * dwarf2loc.c (dwarf2_evaluate_loc_desc_full): Handle DWARF_VALUE_OPTIMIZED_OUT. gdb/testsuite/ * gdb.dwarf2/dw2-entry-value-main.c: New file. * gdb.dwarf2/dw2-entry-value.S: New file. * gdb.dwarf2/dw2-entry-value.exp: New file.
935 lines
24 KiB
C
935 lines
24 KiB
C
/* DWARF 2 Expression Evaluator.
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Copyright (C) 2001, 2002, 2003, 2005, 2007, 2008, 2009, 2010, 2011
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Free Software Foundation, Inc.
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Contributed by Daniel Berlin (dan@dberlin.org)
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#include "defs.h"
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#include "symtab.h"
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#include "gdbtypes.h"
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#include "value.h"
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#include "gdbcore.h"
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#include "dwarf2.h"
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#include "dwarf2expr.h"
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#include "gdb_assert.h"
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/* Local prototypes. */
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static void execute_stack_op (struct dwarf_expr_context *,
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const gdb_byte *, const gdb_byte *);
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/* Create a new context for the expression evaluator. */
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struct dwarf_expr_context *
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new_dwarf_expr_context (void)
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{
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struct dwarf_expr_context *retval;
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retval = xcalloc (1, sizeof (struct dwarf_expr_context));
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retval->stack_len = 0;
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retval->stack_allocated = 10;
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retval->stack = xmalloc (retval->stack_allocated
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* sizeof (struct dwarf_stack_value));
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retval->num_pieces = 0;
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retval->pieces = 0;
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retval->max_recursion_depth = 0x100;
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return retval;
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}
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/* Release the memory allocated to CTX. */
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void
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free_dwarf_expr_context (struct dwarf_expr_context *ctx)
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{
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xfree (ctx->stack);
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xfree (ctx->pieces);
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xfree (ctx);
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}
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/* Helper for make_cleanup_free_dwarf_expr_context. */
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static void
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free_dwarf_expr_context_cleanup (void *arg)
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{
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free_dwarf_expr_context (arg);
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}
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/* Return a cleanup that calls free_dwarf_expr_context. */
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struct cleanup *
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make_cleanup_free_dwarf_expr_context (struct dwarf_expr_context *ctx)
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{
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return make_cleanup (free_dwarf_expr_context_cleanup, ctx);
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}
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/* Expand the memory allocated to CTX's stack to contain at least
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NEED more elements than are currently used. */
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static void
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dwarf_expr_grow_stack (struct dwarf_expr_context *ctx, size_t need)
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{
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if (ctx->stack_len + need > ctx->stack_allocated)
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{
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size_t newlen = ctx->stack_len + need + 10;
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ctx->stack = xrealloc (ctx->stack,
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newlen * sizeof (struct dwarf_stack_value));
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ctx->stack_allocated = newlen;
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}
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}
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/* Push VALUE onto CTX's stack. */
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void
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dwarf_expr_push (struct dwarf_expr_context *ctx, ULONGEST value,
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int in_stack_memory)
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{
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struct dwarf_stack_value *v;
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/* We keep all stack elements within the range defined by the
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DWARF address size. */
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if (ctx->addr_size < sizeof (ULONGEST))
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value &= ((ULONGEST) 1 << (ctx->addr_size * HOST_CHAR_BIT)) - 1;
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dwarf_expr_grow_stack (ctx, 1);
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v = &ctx->stack[ctx->stack_len++];
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v->value = value;
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v->in_stack_memory = in_stack_memory;
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}
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/* Pop the top item off of CTX's stack. */
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void
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dwarf_expr_pop (struct dwarf_expr_context *ctx)
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{
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if (ctx->stack_len <= 0)
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error (_("dwarf expression stack underflow"));
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ctx->stack_len--;
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}
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/* Retrieve the N'th item on CTX's stack. */
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ULONGEST
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dwarf_expr_fetch (struct dwarf_expr_context *ctx, int n)
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{
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if (ctx->stack_len <= n)
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error (_("Asked for position %d of stack, "
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"stack only has %d elements on it."),
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n, ctx->stack_len);
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return ctx->stack[ctx->stack_len - (1 + n)].value;
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}
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/* Retrieve the N'th item on CTX's stack, converted to an address. */
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CORE_ADDR
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dwarf_expr_fetch_address (struct dwarf_expr_context *ctx, int n)
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{
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ULONGEST result = dwarf_expr_fetch (ctx, n);
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/* For most architectures, calling extract_unsigned_integer() alone
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is sufficient for extracting an address. However, some
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architectures (e.g. MIPS) use signed addresses and using
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extract_unsigned_integer() will not produce a correct
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result. Make sure we invoke gdbarch_integer_to_address()
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for those architectures which require it. */
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if (gdbarch_integer_to_address_p (ctx->gdbarch))
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{
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enum bfd_endian byte_order = gdbarch_byte_order (ctx->gdbarch);
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gdb_byte *buf = alloca (ctx->addr_size);
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struct type *int_type;
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switch (ctx->addr_size)
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{
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case 2:
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int_type = builtin_type (ctx->gdbarch)->builtin_uint16;
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break;
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case 4:
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int_type = builtin_type (ctx->gdbarch)->builtin_uint32;
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break;
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case 8:
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int_type = builtin_type (ctx->gdbarch)->builtin_uint64;
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break;
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default:
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internal_error (__FILE__, __LINE__,
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_("Unsupported address size.\n"));
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}
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store_unsigned_integer (buf, ctx->addr_size, byte_order, result);
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return gdbarch_integer_to_address (ctx->gdbarch, int_type, buf);
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}
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return (CORE_ADDR) result;
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}
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/* Retrieve the in_stack_memory flag of the N'th item on CTX's stack. */
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int
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dwarf_expr_fetch_in_stack_memory (struct dwarf_expr_context *ctx, int n)
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{
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if (ctx->stack_len <= n)
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error (_("Asked for position %d of stack, "
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"stack only has %d elements on it."),
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n, ctx->stack_len);
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return ctx->stack[ctx->stack_len - (1 + n)].in_stack_memory;
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}
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/* Return true if the expression stack is empty. */
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static int
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dwarf_expr_stack_empty_p (struct dwarf_expr_context *ctx)
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{
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return ctx->stack_len == 0;
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}
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/* Add a new piece to CTX's piece list. */
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static void
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add_piece (struct dwarf_expr_context *ctx, ULONGEST size, ULONGEST offset)
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{
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struct dwarf_expr_piece *p;
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ctx->num_pieces++;
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ctx->pieces = xrealloc (ctx->pieces,
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(ctx->num_pieces
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* sizeof (struct dwarf_expr_piece)));
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p = &ctx->pieces[ctx->num_pieces - 1];
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p->location = ctx->location;
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p->size = size;
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p->offset = offset;
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if (p->location == DWARF_VALUE_LITERAL)
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{
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p->v.literal.data = ctx->data;
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p->v.literal.length = ctx->len;
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}
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else if (dwarf_expr_stack_empty_p (ctx))
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{
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p->location = DWARF_VALUE_OPTIMIZED_OUT;
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/* Also reset the context's location, for our callers. This is
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a somewhat strange approach, but this lets us avoid setting
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the location to DWARF_VALUE_MEMORY in all the individual
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cases in the evaluator. */
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ctx->location = DWARF_VALUE_OPTIMIZED_OUT;
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}
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else if (p->location == DWARF_VALUE_MEMORY)
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{
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p->v.mem.addr = dwarf_expr_fetch_address (ctx, 0);
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p->v.mem.in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 0);
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}
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else if (p->location == DWARF_VALUE_IMPLICIT_POINTER)
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{
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p->v.ptr.die = ctx->len;
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p->v.ptr.offset = (LONGEST) dwarf_expr_fetch (ctx, 0);
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}
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else
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{
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p->v.value = dwarf_expr_fetch (ctx, 0);
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}
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}
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/* Evaluate the expression at ADDR (LEN bytes long) using the context
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CTX. */
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void
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dwarf_expr_eval (struct dwarf_expr_context *ctx, const gdb_byte *addr,
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size_t len)
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{
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int old_recursion_depth = ctx->recursion_depth;
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execute_stack_op (ctx, addr, addr + len);
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/* CTX RECURSION_DEPTH becomes invalid if an exception was thrown here. */
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gdb_assert (ctx->recursion_depth == old_recursion_depth);
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}
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/* Decode the unsigned LEB128 constant at BUF into the variable pointed to
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by R, and return the new value of BUF. Verify that it doesn't extend
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past BUF_END. */
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const gdb_byte *
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read_uleb128 (const gdb_byte *buf, const gdb_byte *buf_end, ULONGEST * r)
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{
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unsigned shift = 0;
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ULONGEST result = 0;
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gdb_byte byte;
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while (1)
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{
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if (buf >= buf_end)
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error (_("read_uleb128: Corrupted DWARF expression."));
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byte = *buf++;
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result |= (byte & 0x7f) << shift;
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if ((byte & 0x80) == 0)
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break;
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shift += 7;
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}
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*r = result;
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return buf;
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}
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/* Decode the signed LEB128 constant at BUF into the variable pointed to
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by R, and return the new value of BUF. Verify that it doesn't extend
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past BUF_END. */
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const gdb_byte *
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read_sleb128 (const gdb_byte *buf, const gdb_byte *buf_end, LONGEST * r)
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{
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unsigned shift = 0;
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LONGEST result = 0;
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gdb_byte byte;
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while (1)
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{
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if (buf >= buf_end)
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error (_("read_sleb128: Corrupted DWARF expression."));
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byte = *buf++;
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result |= (byte & 0x7f) << shift;
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shift += 7;
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if ((byte & 0x80) == 0)
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break;
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}
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if (shift < (sizeof (*r) * 8) && (byte & 0x40) != 0)
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result |= -(1 << shift);
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*r = result;
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return buf;
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}
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/* Check that the current operator is either at the end of an
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expression, or that it is followed by a composition operator. */
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void
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dwarf_expr_require_composition (const gdb_byte *op_ptr, const gdb_byte *op_end,
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const char *op_name)
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{
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/* It seems like DW_OP_GNU_uninit should be handled here. However,
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it doesn't seem to make sense for DW_OP_*_value, and it was not
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checked at the other place that this function is called. */
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if (op_ptr != op_end && *op_ptr != DW_OP_piece && *op_ptr != DW_OP_bit_piece)
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error (_("DWARF-2 expression error: `%s' operations must be "
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"used either alone or in conjuction with DW_OP_piece "
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"or DW_OP_bit_piece."),
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op_name);
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}
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/* The engine for the expression evaluator. Using the context in CTX,
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evaluate the expression between OP_PTR and OP_END. */
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static void
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execute_stack_op (struct dwarf_expr_context *ctx,
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const gdb_byte *op_ptr, const gdb_byte *op_end)
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{
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#define sign_ext(x) ((LONGEST) (((x) ^ sign_bit) - sign_bit))
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ULONGEST sign_bit = (ctx->addr_size >= sizeof (ULONGEST) ? 0
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: ((ULONGEST) 1) << (ctx->addr_size * 8 - 1));
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enum bfd_endian byte_order = gdbarch_byte_order (ctx->gdbarch);
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ctx->location = DWARF_VALUE_MEMORY;
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ctx->initialized = 1; /* Default is initialized. */
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if (ctx->recursion_depth > ctx->max_recursion_depth)
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error (_("DWARF-2 expression error: Loop detected (%d)."),
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ctx->recursion_depth);
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ctx->recursion_depth++;
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while (op_ptr < op_end)
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{
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enum dwarf_location_atom op = *op_ptr++;
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ULONGEST result;
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/* Assume the value is not in stack memory.
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Code that knows otherwise sets this to 1.
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Some arithmetic on stack addresses can probably be assumed to still
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be a stack address, but we skip this complication for now.
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This is just an optimization, so it's always ok to punt
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and leave this as 0. */
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int in_stack_memory = 0;
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ULONGEST uoffset, reg;
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LONGEST offset;
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switch (op)
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{
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case DW_OP_lit0:
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case DW_OP_lit1:
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case DW_OP_lit2:
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case DW_OP_lit3:
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case DW_OP_lit4:
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case DW_OP_lit5:
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case DW_OP_lit6:
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case DW_OP_lit7:
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case DW_OP_lit8:
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case DW_OP_lit9:
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case DW_OP_lit10:
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case DW_OP_lit11:
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case DW_OP_lit12:
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case DW_OP_lit13:
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case DW_OP_lit14:
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case DW_OP_lit15:
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case DW_OP_lit16:
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case DW_OP_lit17:
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case DW_OP_lit18:
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case DW_OP_lit19:
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case DW_OP_lit20:
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case DW_OP_lit21:
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case DW_OP_lit22:
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case DW_OP_lit23:
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case DW_OP_lit24:
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case DW_OP_lit25:
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case DW_OP_lit26:
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case DW_OP_lit27:
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case DW_OP_lit28:
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case DW_OP_lit29:
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case DW_OP_lit30:
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case DW_OP_lit31:
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result = op - DW_OP_lit0;
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break;
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case DW_OP_addr:
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result = extract_unsigned_integer (op_ptr,
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ctx->addr_size, byte_order);
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op_ptr += ctx->addr_size;
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/* Some versions of GCC emit DW_OP_addr before
|
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DW_OP_GNU_push_tls_address. In this case the value is an
|
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index, not an address. We don't support things like
|
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branching between the address and the TLS op. */
|
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if (op_ptr >= op_end || *op_ptr != DW_OP_GNU_push_tls_address)
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result += ctx->offset;
|
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break;
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|
||
case DW_OP_const1u:
|
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result = extract_unsigned_integer (op_ptr, 1, byte_order);
|
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op_ptr += 1;
|
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break;
|
||
case DW_OP_const1s:
|
||
result = extract_signed_integer (op_ptr, 1, byte_order);
|
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op_ptr += 1;
|
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break;
|
||
case DW_OP_const2u:
|
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result = extract_unsigned_integer (op_ptr, 2, byte_order);
|
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op_ptr += 2;
|
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break;
|
||
case DW_OP_const2s:
|
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result = extract_signed_integer (op_ptr, 2, byte_order);
|
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op_ptr += 2;
|
||
break;
|
||
case DW_OP_const4u:
|
||
result = extract_unsigned_integer (op_ptr, 4, byte_order);
|
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op_ptr += 4;
|
||
break;
|
||
case DW_OP_const4s:
|
||
result = extract_signed_integer (op_ptr, 4, byte_order);
|
||
op_ptr += 4;
|
||
break;
|
||
case DW_OP_const8u:
|
||
result = extract_unsigned_integer (op_ptr, 8, byte_order);
|
||
op_ptr += 8;
|
||
break;
|
||
case DW_OP_const8s:
|
||
result = 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);
|
||
result = uoffset;
|
||
break;
|
||
case DW_OP_consts:
|
||
op_ptr = read_sleb128 (op_ptr, op_end, &offset);
|
||
result = offset;
|
||
break;
|
||
|
||
/* The DW_OP_reg operations are required to occur alone in
|
||
location expressions. */
|
||
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:
|
||
if (op_ptr != op_end
|
||
&& *op_ptr != DW_OP_piece
|
||
&& *op_ptr != DW_OP_bit_piece
|
||
&& *op_ptr != DW_OP_GNU_uninit)
|
||
error (_("DWARF-2 expression error: DW_OP_reg operations must be "
|
||
"used either alone or in conjuction with DW_OP_piece "
|
||
"or DW_OP_bit_piece."));
|
||
|
||
result = op - DW_OP_reg0;
|
||
ctx->location = DWARF_VALUE_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");
|
||
|
||
result = reg;
|
||
ctx->location = DWARF_VALUE_REGISTER;
|
||
break;
|
||
|
||
case DW_OP_implicit_value:
|
||
{
|
||
ULONGEST len;
|
||
|
||
op_ptr = read_uleb128 (op_ptr, op_end, &len);
|
||
if (op_ptr + len > op_end)
|
||
error (_("DW_OP_implicit_value: too few bytes available."));
|
||
ctx->len = len;
|
||
ctx->data = op_ptr;
|
||
ctx->location = DWARF_VALUE_LITERAL;
|
||
op_ptr += len;
|
||
dwarf_expr_require_composition (op_ptr, op_end,
|
||
"DW_OP_implicit_value");
|
||
}
|
||
goto no_push;
|
||
|
||
case DW_OP_stack_value:
|
||
ctx->location = DWARF_VALUE_STACK;
|
||
dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_stack_value");
|
||
goto no_push;
|
||
|
||
case DW_OP_GNU_implicit_pointer:
|
||
{
|
||
ULONGEST die;
|
||
LONGEST len;
|
||
|
||
/* The referred-to DIE. */
|
||
ctx->len = extract_unsigned_integer (op_ptr, ctx->addr_size,
|
||
byte_order);
|
||
op_ptr += ctx->addr_size;
|
||
|
||
/* The byte offset into the data. */
|
||
op_ptr = read_sleb128 (op_ptr, op_end, &len);
|
||
result = (ULONGEST) len;
|
||
|
||
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_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);
|
||
result = (ctx->read_reg) (ctx->baton, op - DW_OP_breg0);
|
||
result += offset;
|
||
}
|
||
break;
|
||
case DW_OP_bregx:
|
||
{
|
||
op_ptr = read_uleb128 (op_ptr, op_end, ®);
|
||
op_ptr = read_sleb128 (op_ptr, op_end, &offset);
|
||
result = (ctx->read_reg) (ctx->baton, reg);
|
||
result += offset;
|
||
}
|
||
break;
|
||
case DW_OP_fbreg:
|
||
{
|
||
const gdb_byte *datastart;
|
||
size_t datalen;
|
||
unsigned int before_stack_len;
|
||
|
||
op_ptr = read_sleb128 (op_ptr, op_end, &offset);
|
||
/* Rather than create a whole new context, we simply
|
||
record the stack length before execution, then reset it
|
||
afterwards, effectively erasing whatever the recursive
|
||
call put there. */
|
||
before_stack_len = ctx->stack_len;
|
||
/* FIXME: cagney/2003-03-26: This code should be using
|
||
get_frame_base_address(), and then implement a dwarf2
|
||
specific this_base method. */
|
||
(ctx->get_frame_base) (ctx->baton, &datastart, &datalen);
|
||
dwarf_expr_eval (ctx, datastart, datalen);
|
||
if (ctx->location == DWARF_VALUE_MEMORY)
|
||
result = dwarf_expr_fetch_address (ctx, 0);
|
||
else if (ctx->location == DWARF_VALUE_REGISTER)
|
||
result = (ctx->read_reg) (ctx->baton, dwarf_expr_fetch (ctx, 0));
|
||
else
|
||
error (_("Not implemented: computing frame "
|
||
"base using explicit value operator"));
|
||
result = result + offset;
|
||
in_stack_memory = 1;
|
||
ctx->stack_len = before_stack_len;
|
||
ctx->location = DWARF_VALUE_MEMORY;
|
||
}
|
||
break;
|
||
|
||
case DW_OP_dup:
|
||
result = dwarf_expr_fetch (ctx, 0);
|
||
in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 0);
|
||
break;
|
||
|
||
case DW_OP_drop:
|
||
dwarf_expr_pop (ctx);
|
||
goto no_push;
|
||
|
||
case DW_OP_pick:
|
||
offset = *op_ptr++;
|
||
result = 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);
|
||
in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 1);
|
||
break;
|
||
|
||
case DW_OP_rot:
|
||
{
|
||
struct dwarf_stack_value t1, t2, t3;
|
||
|
||
if (ctx->stack_len < 3)
|
||
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];
|
||
t3 = ctx->stack[ctx->stack_len - 3];
|
||
ctx->stack[ctx->stack_len - 1] = t2;
|
||
ctx->stack[ctx->stack_len - 2] = t3;
|
||
ctx->stack[ctx->stack_len - 3] = t1;
|
||
goto no_push;
|
||
}
|
||
|
||
case DW_OP_deref:
|
||
case DW_OP_deref_size:
|
||
{
|
||
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);
|
||
dwarf_expr_pop (ctx);
|
||
|
||
(ctx->read_mem) (ctx->baton, buf, addr, addr_size);
|
||
result = extract_unsigned_integer (buf, addr_size, byte_order);
|
||
break;
|
||
}
|
||
|
||
case DW_OP_abs:
|
||
case DW_OP_neg:
|
||
case DW_OP_not:
|
||
case DW_OP_plus_uconst:
|
||
/* Unary operations. */
|
||
result = dwarf_expr_fetch (ctx, 0);
|
||
dwarf_expr_pop (ctx);
|
||
|
||
switch (op)
|
||
{
|
||
case DW_OP_abs:
|
||
if (sign_ext (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_div:
|
||
case DW_OP_minus:
|
||
case DW_OP_mod:
|
||
case DW_OP_mul:
|
||
case DW_OP_or:
|
||
case DW_OP_plus:
|
||
case DW_OP_shl:
|
||
case DW_OP_shr:
|
||
case DW_OP_shra:
|
||
case DW_OP_xor:
|
||
case DW_OP_le:
|
||
case DW_OP_ge:
|
||
case DW_OP_eq:
|
||
case DW_OP_lt:
|
||
case DW_OP_gt:
|
||
case DW_OP_ne:
|
||
{
|
||
/* Binary operations. */
|
||
ULONGEST first, second;
|
||
|
||
second = dwarf_expr_fetch (ctx, 0);
|
||
dwarf_expr_pop (ctx);
|
||
|
||
first = dwarf_expr_fetch (ctx, 0);
|
||
dwarf_expr_pop (ctx);
|
||
|
||
switch (op)
|
||
{
|
||
case DW_OP_and:
|
||
result = first & second;
|
||
break;
|
||
case DW_OP_div:
|
||
if (!second)
|
||
error (_("Division by zero"));
|
||
result = sign_ext (first) / sign_ext (second);
|
||
break;
|
||
case DW_OP_minus:
|
||
result = first - second;
|
||
break;
|
||
case DW_OP_mod:
|
||
if (!second)
|
||
error (_("Division by zero"));
|
||
result = first % second;
|
||
break;
|
||
case DW_OP_mul:
|
||
result = first * second;
|
||
break;
|
||
case DW_OP_or:
|
||
result = first | second;
|
||
break;
|
||
case DW_OP_plus:
|
||
result = first + second;
|
||
break;
|
||
case DW_OP_shl:
|
||
result = first << second;
|
||
break;
|
||
case DW_OP_shr:
|
||
result = first >> second;
|
||
break;
|
||
case DW_OP_shra:
|
||
result = sign_ext (first) >> second;
|
||
break;
|
||
case DW_OP_xor:
|
||
result = first ^ second;
|
||
break;
|
||
case DW_OP_le:
|
||
result = sign_ext (first) <= sign_ext (second);
|
||
break;
|
||
case DW_OP_ge:
|
||
result = sign_ext (first) >= sign_ext (second);
|
||
break;
|
||
case DW_OP_eq:
|
||
result = sign_ext (first) == sign_ext (second);
|
||
break;
|
||
case DW_OP_lt:
|
||
result = sign_ext (first) < sign_ext (second);
|
||
break;
|
||
case DW_OP_gt:
|
||
result = sign_ext (first) > sign_ext (second);
|
||
break;
|
||
case DW_OP_ne:
|
||
result = sign_ext (first) != sign_ext (second);
|
||
break;
|
||
default:
|
||
internal_error (__FILE__, __LINE__,
|
||
_("Can't be reached."));
|
||
}
|
||
}
|
||
break;
|
||
|
||
case DW_OP_call_frame_cfa:
|
||
result = (ctx->get_frame_cfa) (ctx->baton);
|
||
in_stack_memory = 1;
|
||
break;
|
||
|
||
case DW_OP_GNU_push_tls_address:
|
||
/* Variable is at a constant offset in the thread-local
|
||
storage block into the objfile for the current thread and
|
||
the dynamic linker module containing this expression. Here
|
||
we return returns the offset from that base. The top of the
|
||
stack has the offset from the beginning of the thread
|
||
control block at which the variable is located. Nothing
|
||
should follow this operator, so the top of stack would be
|
||
returned. */
|
||
result = dwarf_expr_fetch (ctx, 0);
|
||
dwarf_expr_pop (ctx);
|
||
result = (ctx->get_tls_address) (ctx->baton, result);
|
||
break;
|
||
|
||
case DW_OP_skip:
|
||
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, byte_order);
|
||
op_ptr += 2;
|
||
if (dwarf_expr_fetch (ctx, 0) != 0)
|
||
op_ptr += offset;
|
||
dwarf_expr_pop (ctx);
|
||
goto no_push;
|
||
|
||
case DW_OP_nop:
|
||
goto no_push;
|
||
|
||
case DW_OP_piece:
|
||
{
|
||
ULONGEST size;
|
||
|
||
/* Record the piece. */
|
||
op_ptr = 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:
|
||
{
|
||
ULONGEST size, offset;
|
||
|
||
/* Record the piece. */
|
||
op_ptr = read_uleb128 (op_ptr, op_end, &size);
|
||
op_ptr = read_uleb128 (op_ptr, op_end, &offset);
|
||
add_piece (ctx, size, offset);
|
||
|
||
/* Pop off the address/regnum, and reset the location
|
||
type. */
|
||
if (ctx->location != DWARF_VALUE_LITERAL
|
||
&& ctx->location != DWARF_VALUE_OPTIMIZED_OUT)
|
||
dwarf_expr_pop (ctx);
|
||
ctx->location = DWARF_VALUE_MEMORY;
|
||
}
|
||
goto no_push;
|
||
|
||
case DW_OP_GNU_uninit:
|
||
if (op_ptr != op_end)
|
||
error (_("DWARF-2 expression error: DW_OP_GNU_uninit must always "
|
||
"be the very last op."));
|
||
|
||
ctx->initialized = 0;
|
||
goto no_push;
|
||
|
||
case DW_OP_call2:
|
||
result = extract_unsigned_integer (op_ptr, 2, byte_order);
|
||
op_ptr += 2;
|
||
ctx->dwarf_call (ctx, result);
|
||
goto no_push;
|
||
|
||
case DW_OP_call4:
|
||
result = extract_unsigned_integer (op_ptr, 4, byte_order);
|
||
op_ptr += 4;
|
||
ctx->dwarf_call (ctx, result);
|
||
goto no_push;
|
||
|
||
case DW_OP_GNU_entry_value:
|
||
/* This operation is not yet supported by GDB. */
|
||
ctx->location = DWARF_VALUE_OPTIMIZED_OUT;
|
||
ctx->stack_len = 0;
|
||
ctx->num_pieces = 0;
|
||
goto abort_expression;
|
||
|
||
default:
|
||
error (_("Unhandled dwarf expression opcode 0x%x"), op);
|
||
}
|
||
|
||
/* Most things push a result value. */
|
||
dwarf_expr_push (ctx, result, 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);
|
||
#undef sign_ext
|
||
}
|