mirror of
https://sourceware.org/git/binutils-gdb.git
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bb2ec1b34e
This final patch adds the new "compile" command and subcommands, and all the machinery needed to make it work. A shared library supplied by gcc is used for all communications with gcc. Types and most aspects of symbols are provided directly by gdb to the compiler using this library. gdb provides some information about the user's code using plain text. Macros are emitted this way, and DWARF location expressions (and bounds for VLA) are compiled to C code. This hybrid approach was taken because, on the one hand, it is better to provide global declarations and such on demand; but on the other hand, for local variables, translating DWARF location expressions to C was much simpler than exporting a full compiler API to gdb -- the same result, only easier to implement, understand, and debug. In the ordinary mode, the user's expression is wrapped in a dummy function. After compilation, gdb inserts the resulting object code into the inferior, then calls this function. Access to local variables is provided by noting which registers are used by location expressions, and passing a structure of register values into the function. Writes to registers are supported by copying out these values after the function returns. This approach was taken so that we could eventually implement other more interesting features based on this same infrastructure; for example, we're planning to investigate inferior-side breakpoint conditions. gdb/ChangeLog 2014-12-12 Phil Muldoon <pmuldoon@redhat.com> Jan Kratochvil <jan.kratochvil@redhat.com> Tom Tromey <tromey@redhat.com> * NEWS: Update. * symtab.h (struct symbol_computed_ops) <generate_c_location>: New field. * p-lang.c (pascal_language_defn): Update. * opencl-lang.c (opencl_language_defn): Update. * objc-lang.c (objc_language_defn): Update. * m2-lang.c (m2_language_defn): Update. * language.h (struct language_defn) <la_get_compile_instance, la_compute_program>: New fields. * language.c (unknown_language_defn, auto_language_defn) (local_language_defn): Update. * jv-lang.c (java_language_defn): Update. * go-lang.c (go_language_defn): Update. * f-lang.c (f_language_defn): Update. * dwarf2loc.h (dwarf2_compile_property_to_c): Declare. * dwarf2loc.c (dwarf2_compile_property_to_c) (locexpr_generate_c_location, loclist_generate_c_location): New functions. (dwarf2_locexpr_funcs, dwarf2_loclist_funcs): Update. * defs.h (enum compile_i_scope_types): New. (enum command_control_type) <compile_control>: New constant. (struct command_line) <control_u>: New field. * d-lang.c (d_language_defn): Update. * compile/compile.c: New file. * compile/compile-c-support.c: New file. * compile/compile-c-symbols.c: New file. * compile/compile-c-types.c: New file. * compile/compile.h: New file. * compile/compile-internal.h: New file. * compile/compile-loc2c.c: New file. * compile/compile-object-load.c: New file. * compile/compile-object-load.h: New file. * compile/compile-object-run.c: New file. * compile/compile-object-run.h: New file. * cli/cli-script.c (multi_line_command_p, print_command_lines) (execute_control_command, process_next_line) (recurse_read_control_structure): Handle compile_control. * c-lang.h (c_get_compile_context, c_compute_program): Declare. * c-lang.c (c_language_defn, cplus_language_defn) (asm_language_defn, minimal_language_defn): Update. * ada-lang.c (ada_language_defn): Update. * Makefile.in (SUBDIR_GCC_COMPILE_OBS, SUBDIR_GCC_COMPILE_SRCS): New variables. (SFILES): Add SUBDIR_GCC_COMPILE_SRCS. (HFILES_NO_SRCDIR): Add compile.h. (COMMON_OBS): Add SUBDIR_GCC_COMPILE_OBS. (INIT_FILES): Add SUBDIR_GCC_COMPILE_SRCS. (compile.o, compile-c-types.o, compile-c-symbols.o) (compile-object-load.o, compile-object-run.o, compile-loc2c.o) (compile-c-support.o): New targets. gdb/doc/ChangeLog 2014-12-12 Phil Muldoon <pmuldoon@redhat.com> Jan Kratochvil <jan.kratochvil@redhat.com> * gdb.texinfo (Altering): Update. (Compiling and Injecting Code): New node. gdb/testsuite/ChangeLog 2014-12-12 Phil Muldoon <pmuldoon@redhat.com> Jan Kratochvil <jan.kratochvil@redhat.com> Tom Tromey <tromey@redhat.com> * configure.ac: Add gdb.compile/. * configure: Regenerate. * gdb.compile/Makefile.in: New file. * gdb.compile/compile-ops.exp: New file. * gdb.compile/compile-ops.c: New file. * gdb.compile/compile-tls.c: New file. * gdb.compile/compile-tls.exp: New file. * gdb.compile/compile-constvar.S: New file. * gdb.compile/compile-constvar.c: New file. * gdb.compile/compile-mod.c: New file. * gdb.compile/compile-nodebug.c: New file. * gdb.compile/compile-setjmp-mod.c: New file. * gdb.compile/compile-setjmp.c: New file. * gdb.compile/compile-setjmp.exp: New file. * gdb.compile/compile-shlib.c: New file. * gdb.compile/compile.c: New file. * gdb.compile/compile.exp: New file. * lib/gdb.exp (skip_compile_feature_tests): New proc.
4473 lines
125 KiB
C
4473 lines
125 KiB
C
/* DWARF 2 location expression support for GDB.
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Copyright (C) 2003-2014 Free Software Foundation, Inc.
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Contributed by Daniel Jacobowitz, MontaVista Software, Inc.
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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 "ui-out.h"
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#include "value.h"
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#include "frame.h"
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#include "gdbcore.h"
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#include "target.h"
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#include "inferior.h"
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#include "ax.h"
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#include "ax-gdb.h"
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#include "regcache.h"
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#include "objfiles.h"
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#include "block.h"
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#include "gdbcmd.h"
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#include "dwarf2.h"
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#include "dwarf2expr.h"
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#include "dwarf2loc.h"
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#include "dwarf2-frame.h"
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#include "compile/compile.h"
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extern int dwarf2_always_disassemble;
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static const struct dwarf_expr_context_funcs dwarf_expr_ctx_funcs;
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static struct value *dwarf2_evaluate_loc_desc_full (struct type *type,
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struct frame_info *frame,
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const gdb_byte *data,
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size_t size,
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struct dwarf2_per_cu_data *per_cu,
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LONGEST byte_offset);
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/* Until these have formal names, we define these here.
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ref: http://gcc.gnu.org/wiki/DebugFission
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Each entry in .debug_loc.dwo begins with a byte that describes the entry,
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and is then followed by data specific to that entry. */
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enum debug_loc_kind
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{
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/* Indicates the end of the list of entries. */
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DEBUG_LOC_END_OF_LIST = 0,
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/* This is followed by an unsigned LEB128 number that is an index into
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.debug_addr and specifies the base address for all following entries. */
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DEBUG_LOC_BASE_ADDRESS = 1,
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/* This is followed by two unsigned LEB128 numbers that are indices into
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.debug_addr and specify the beginning and ending addresses, and then
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a normal location expression as in .debug_loc. */
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DEBUG_LOC_START_END = 2,
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/* This is followed by an unsigned LEB128 number that is an index into
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.debug_addr and specifies the beginning address, and a 4 byte unsigned
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number that specifies the length, and then a normal location expression
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as in .debug_loc. */
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DEBUG_LOC_START_LENGTH = 3,
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/* An internal value indicating there is insufficient data. */
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DEBUG_LOC_BUFFER_OVERFLOW = -1,
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/* An internal value indicating an invalid kind of entry was found. */
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DEBUG_LOC_INVALID_ENTRY = -2
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};
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/* Helper function which throws an error if a synthetic pointer is
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invalid. */
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static void
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invalid_synthetic_pointer (void)
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{
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error (_("access outside bounds of object "
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"referenced via synthetic pointer"));
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}
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/* Decode the addresses in a non-dwo .debug_loc entry.
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A pointer to the next byte to examine is returned in *NEW_PTR.
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The encoded low,high addresses are return in *LOW,*HIGH.
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The result indicates the kind of entry found. */
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static enum debug_loc_kind
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decode_debug_loc_addresses (const gdb_byte *loc_ptr, const gdb_byte *buf_end,
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const gdb_byte **new_ptr,
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CORE_ADDR *low, CORE_ADDR *high,
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enum bfd_endian byte_order,
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unsigned int addr_size,
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int signed_addr_p)
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{
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CORE_ADDR base_mask = ~(~(CORE_ADDR)1 << (addr_size * 8 - 1));
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if (buf_end - loc_ptr < 2 * addr_size)
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return DEBUG_LOC_BUFFER_OVERFLOW;
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if (signed_addr_p)
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*low = extract_signed_integer (loc_ptr, addr_size, byte_order);
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else
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*low = extract_unsigned_integer (loc_ptr, addr_size, byte_order);
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loc_ptr += addr_size;
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if (signed_addr_p)
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*high = extract_signed_integer (loc_ptr, addr_size, byte_order);
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else
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*high = extract_unsigned_integer (loc_ptr, addr_size, byte_order);
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loc_ptr += addr_size;
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*new_ptr = loc_ptr;
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/* A base-address-selection entry. */
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if ((*low & base_mask) == base_mask)
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return DEBUG_LOC_BASE_ADDRESS;
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/* An end-of-list entry. */
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if (*low == 0 && *high == 0)
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return DEBUG_LOC_END_OF_LIST;
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return DEBUG_LOC_START_END;
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}
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/* Decode the addresses in .debug_loc.dwo entry.
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A pointer to the next byte to examine is returned in *NEW_PTR.
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The encoded low,high addresses are return in *LOW,*HIGH.
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The result indicates the kind of entry found. */
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static enum debug_loc_kind
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decode_debug_loc_dwo_addresses (struct dwarf2_per_cu_data *per_cu,
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const gdb_byte *loc_ptr,
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const gdb_byte *buf_end,
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const gdb_byte **new_ptr,
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CORE_ADDR *low, CORE_ADDR *high,
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enum bfd_endian byte_order)
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{
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uint64_t low_index, high_index;
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if (loc_ptr == buf_end)
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return DEBUG_LOC_BUFFER_OVERFLOW;
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switch (*loc_ptr++)
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{
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case DEBUG_LOC_END_OF_LIST:
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*new_ptr = loc_ptr;
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return DEBUG_LOC_END_OF_LIST;
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case DEBUG_LOC_BASE_ADDRESS:
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*low = 0;
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loc_ptr = gdb_read_uleb128 (loc_ptr, buf_end, &high_index);
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if (loc_ptr == NULL)
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return DEBUG_LOC_BUFFER_OVERFLOW;
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*high = dwarf2_read_addr_index (per_cu, high_index);
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*new_ptr = loc_ptr;
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return DEBUG_LOC_BASE_ADDRESS;
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case DEBUG_LOC_START_END:
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loc_ptr = gdb_read_uleb128 (loc_ptr, buf_end, &low_index);
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if (loc_ptr == NULL)
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return DEBUG_LOC_BUFFER_OVERFLOW;
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*low = dwarf2_read_addr_index (per_cu, low_index);
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loc_ptr = gdb_read_uleb128 (loc_ptr, buf_end, &high_index);
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if (loc_ptr == NULL)
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return DEBUG_LOC_BUFFER_OVERFLOW;
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*high = dwarf2_read_addr_index (per_cu, high_index);
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*new_ptr = loc_ptr;
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return DEBUG_LOC_START_END;
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case DEBUG_LOC_START_LENGTH:
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loc_ptr = gdb_read_uleb128 (loc_ptr, buf_end, &low_index);
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if (loc_ptr == NULL)
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return DEBUG_LOC_BUFFER_OVERFLOW;
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*low = dwarf2_read_addr_index (per_cu, low_index);
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if (loc_ptr + 4 > buf_end)
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return DEBUG_LOC_BUFFER_OVERFLOW;
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*high = *low;
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*high += extract_unsigned_integer (loc_ptr, 4, byte_order);
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*new_ptr = loc_ptr + 4;
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return DEBUG_LOC_START_LENGTH;
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default:
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return DEBUG_LOC_INVALID_ENTRY;
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}
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}
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/* A function for dealing with location lists. Given a
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symbol baton (BATON) and a pc value (PC), find the appropriate
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location expression, set *LOCEXPR_LENGTH, and return a pointer
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to the beginning of the expression. Returns NULL on failure.
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For now, only return the first matching location expression; there
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can be more than one in the list. */
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const gdb_byte *
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dwarf2_find_location_expression (struct dwarf2_loclist_baton *baton,
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size_t *locexpr_length, CORE_ADDR pc)
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{
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struct objfile *objfile = dwarf2_per_cu_objfile (baton->per_cu);
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struct gdbarch *gdbarch = get_objfile_arch (objfile);
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enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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unsigned int addr_size = dwarf2_per_cu_addr_size (baton->per_cu);
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int signed_addr_p = bfd_get_sign_extend_vma (objfile->obfd);
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/* Adjust base_address for relocatable objects. */
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CORE_ADDR base_offset = dwarf2_per_cu_text_offset (baton->per_cu);
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CORE_ADDR base_address = baton->base_address + base_offset;
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const gdb_byte *loc_ptr, *buf_end;
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loc_ptr = baton->data;
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buf_end = baton->data + baton->size;
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while (1)
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{
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CORE_ADDR low = 0, high = 0; /* init for gcc -Wall */
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int length;
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enum debug_loc_kind kind;
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const gdb_byte *new_ptr = NULL; /* init for gcc -Wall */
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if (baton->from_dwo)
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kind = decode_debug_loc_dwo_addresses (baton->per_cu,
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loc_ptr, buf_end, &new_ptr,
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&low, &high, byte_order);
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else
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kind = decode_debug_loc_addresses (loc_ptr, buf_end, &new_ptr,
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&low, &high,
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byte_order, addr_size,
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signed_addr_p);
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loc_ptr = new_ptr;
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switch (kind)
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{
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case DEBUG_LOC_END_OF_LIST:
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*locexpr_length = 0;
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return NULL;
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case DEBUG_LOC_BASE_ADDRESS:
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base_address = high + base_offset;
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continue;
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case DEBUG_LOC_START_END:
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case DEBUG_LOC_START_LENGTH:
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break;
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case DEBUG_LOC_BUFFER_OVERFLOW:
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case DEBUG_LOC_INVALID_ENTRY:
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error (_("dwarf2_find_location_expression: "
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"Corrupted DWARF expression."));
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default:
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gdb_assert_not_reached ("bad debug_loc_kind");
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}
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/* Otherwise, a location expression entry.
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If the entry is from a DWO, don't add base address: the entry is
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from .debug_addr which has absolute addresses. */
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if (! baton->from_dwo)
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{
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low += base_address;
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high += base_address;
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}
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length = extract_unsigned_integer (loc_ptr, 2, byte_order);
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loc_ptr += 2;
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if (low == high && pc == low)
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{
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/* This is entry PC record present only at entry point
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of a function. Verify it is really the function entry point. */
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const struct block *pc_block = block_for_pc (pc);
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struct symbol *pc_func = NULL;
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if (pc_block)
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pc_func = block_linkage_function (pc_block);
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if (pc_func && pc == BLOCK_START (SYMBOL_BLOCK_VALUE (pc_func)))
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{
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*locexpr_length = length;
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return loc_ptr;
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}
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}
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if (pc >= low && pc < high)
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{
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*locexpr_length = length;
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return loc_ptr;
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}
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loc_ptr += length;
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}
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}
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/* This is the baton used when performing dwarf2 expression
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evaluation. */
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struct dwarf_expr_baton
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{
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struct frame_info *frame;
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struct dwarf2_per_cu_data *per_cu;
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CORE_ADDR obj_address;
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};
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/* Helper functions for dwarf2_evaluate_loc_desc. */
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/* Using the frame specified in BATON, return the value of register
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REGNUM, treated as a pointer. */
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static CORE_ADDR
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dwarf_expr_read_addr_from_reg (void *baton, int dwarf_regnum)
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{
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struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton;
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struct gdbarch *gdbarch = get_frame_arch (debaton->frame);
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int regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, dwarf_regnum);
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return address_from_register (regnum, debaton->frame);
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}
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/* Implement struct dwarf_expr_context_funcs' "get_reg_value" callback. */
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static struct value *
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dwarf_expr_get_reg_value (void *baton, struct type *type, int dwarf_regnum)
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{
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struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton;
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struct gdbarch *gdbarch = get_frame_arch (debaton->frame);
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int regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, dwarf_regnum);
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return value_from_register (type, regnum, debaton->frame);
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}
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/* Read memory at ADDR (length LEN) into BUF. */
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static void
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dwarf_expr_read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len)
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{
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read_memory (addr, buf, len);
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}
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/* Using the frame specified in BATON, find the location expression
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describing the frame base. Return a pointer to it in START and
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its length in LENGTH. */
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static void
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dwarf_expr_frame_base (void *baton, const gdb_byte **start, size_t * length)
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{
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/* FIXME: cagney/2003-03-26: This code should be using
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get_frame_base_address(), and then implement a dwarf2 specific
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this_base method. */
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struct symbol *framefunc;
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struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton;
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const struct block *bl = get_frame_block (debaton->frame, NULL);
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if (bl == NULL)
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error (_("frame address is not available."));
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/* Use block_linkage_function, which returns a real (not inlined)
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function, instead of get_frame_function, which may return an
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inlined function. */
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framefunc = block_linkage_function (bl);
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/* If we found a frame-relative symbol then it was certainly within
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some function associated with a frame. If we can't find the frame,
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something has gone wrong. */
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gdb_assert (framefunc != NULL);
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func_get_frame_base_dwarf_block (framefunc,
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get_frame_address_in_block (debaton->frame),
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start, length);
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}
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/* Implement find_frame_base_location method for LOC_BLOCK functions using
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DWARF expression for its DW_AT_frame_base. */
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static void
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locexpr_find_frame_base_location (struct symbol *framefunc, CORE_ADDR pc,
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const gdb_byte **start, size_t *length)
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{
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struct dwarf2_locexpr_baton *symbaton = SYMBOL_LOCATION_BATON (framefunc);
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*length = symbaton->size;
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*start = symbaton->data;
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}
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/* Vector for inferior functions as represented by LOC_BLOCK, if the inferior
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function uses DWARF expression for its DW_AT_frame_base. */
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const struct symbol_block_ops dwarf2_block_frame_base_locexpr_funcs =
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{
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locexpr_find_frame_base_location
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};
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/* Implement find_frame_base_location method for LOC_BLOCK functions using
|
||
DWARF location list for its DW_AT_frame_base. */
|
||
|
||
static void
|
||
loclist_find_frame_base_location (struct symbol *framefunc, CORE_ADDR pc,
|
||
const gdb_byte **start, size_t *length)
|
||
{
|
||
struct dwarf2_loclist_baton *symbaton = SYMBOL_LOCATION_BATON (framefunc);
|
||
|
||
*start = dwarf2_find_location_expression (symbaton, length, pc);
|
||
}
|
||
|
||
/* Vector for inferior functions as represented by LOC_BLOCK, if the inferior
|
||
function uses DWARF location list for its DW_AT_frame_base. */
|
||
|
||
const struct symbol_block_ops dwarf2_block_frame_base_loclist_funcs =
|
||
{
|
||
loclist_find_frame_base_location
|
||
};
|
||
|
||
/* See dwarf2loc.h. */
|
||
|
||
void
|
||
func_get_frame_base_dwarf_block (struct symbol *framefunc, CORE_ADDR pc,
|
||
const gdb_byte **start, size_t *length)
|
||
{
|
||
if (SYMBOL_BLOCK_OPS (framefunc) != NULL)
|
||
{
|
||
const struct symbol_block_ops *ops_block = SYMBOL_BLOCK_OPS (framefunc);
|
||
|
||
ops_block->find_frame_base_location (framefunc, pc, start, length);
|
||
}
|
||
else
|
||
*length = 0;
|
||
|
||
if (*length == 0)
|
||
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);
|
||
}
|
||
|
||
/* Helper function for dwarf2_evaluate_loc_desc. Computes the PC for
|
||
the frame in BATON. */
|
||
|
||
static CORE_ADDR
|
||
dwarf_expr_frame_pc (void *baton)
|
||
{
|
||
struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton;
|
||
|
||
return get_frame_address_in_block (debaton->frame);
|
||
}
|
||
|
||
/* Using the objfile specified in BATON, find the address for the
|
||
current thread's thread-local storage with offset OFFSET. */
|
||
static CORE_ADDR
|
||
dwarf_expr_tls_address (void *baton, CORE_ADDR offset)
|
||
{
|
||
struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton;
|
||
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, cu_offset die_offset,
|
||
struct dwarf2_per_cu_data *per_cu,
|
||
CORE_ADDR (*get_frame_pc) (void *baton),
|
||
void *baton)
|
||
{
|
||
struct dwarf2_locexpr_baton block;
|
||
|
||
block = dwarf2_fetch_die_loc_cu_off (die_offset, per_cu, get_frame_pc, baton);
|
||
|
||
/* 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, cu_offset die_offset)
|
||
{
|
||
struct dwarf_expr_baton *debaton = ctx->baton;
|
||
|
||
per_cu_dwarf_call (ctx, die_offset, debaton->per_cu,
|
||
ctx->funcs->get_frame_pc, ctx->baton);
|
||
}
|
||
|
||
/* Callback function for dwarf2_evaluate_loc_desc. */
|
||
|
||
static struct type *
|
||
dwarf_expr_get_base_type (struct dwarf_expr_context *ctx,
|
||
cu_offset die_offset)
|
||
{
|
||
struct dwarf_expr_baton *debaton = ctx->baton;
|
||
|
||
return dwarf2_get_die_type (die_offset, debaton->per_cu);
|
||
}
|
||
|
||
/* See dwarf2loc.h. */
|
||
|
||
unsigned int entry_values_debug = 0;
|
||
|
||
/* Helper to set entry_values_debug. */
|
||
|
||
static void
|
||
show_entry_values_debug (struct ui_file *file, int from_tty,
|
||
struct cmd_list_element *c, const char *value)
|
||
{
|
||
fprintf_filtered (file,
|
||
_("Entry values and tail call frames debugging is %s.\n"),
|
||
value);
|
||
}
|
||
|
||
/* Find DW_TAG_GNU_call_site's DW_AT_GNU_call_site_target address.
|
||
CALLER_FRAME (for registers) can be NULL if it is not known. This function
|
||
always returns valid address or it throws NO_ENTRY_VALUE_ERROR. */
|
||
|
||
static CORE_ADDR
|
||
call_site_to_target_addr (struct gdbarch *call_site_gdbarch,
|
||
struct call_site *call_site,
|
||
struct frame_info *caller_frame)
|
||
{
|
||
switch (FIELD_LOC_KIND (call_site->target))
|
||
{
|
||
case FIELD_LOC_KIND_DWARF_BLOCK:
|
||
{
|
||
struct dwarf2_locexpr_baton *dwarf_block;
|
||
struct value *val;
|
||
struct type *caller_core_addr_type;
|
||
struct gdbarch *caller_arch;
|
||
|
||
dwarf_block = FIELD_DWARF_BLOCK (call_site->target);
|
||
if (dwarf_block == NULL)
|
||
{
|
||
struct bound_minimal_symbol msym;
|
||
|
||
msym = lookup_minimal_symbol_by_pc (call_site->pc - 1);
|
||
throw_error (NO_ENTRY_VALUE_ERROR,
|
||
_("DW_AT_GNU_call_site_target is not specified "
|
||
"at %s in %s"),
|
||
paddress (call_site_gdbarch, call_site->pc),
|
||
(msym.minsym == NULL ? "???"
|
||
: MSYMBOL_PRINT_NAME (msym.minsym)));
|
||
|
||
}
|
||
if (caller_frame == NULL)
|
||
{
|
||
struct bound_minimal_symbol msym;
|
||
|
||
msym = lookup_minimal_symbol_by_pc (call_site->pc - 1);
|
||
throw_error (NO_ENTRY_VALUE_ERROR,
|
||
_("DW_AT_GNU_call_site_target DWARF block resolving "
|
||
"requires known frame which is currently not "
|
||
"available at %s in %s"),
|
||
paddress (call_site_gdbarch, call_site->pc),
|
||
(msym.minsym == NULL ? "???"
|
||
: MSYMBOL_PRINT_NAME (msym.minsym)));
|
||
|
||
}
|
||
caller_arch = get_frame_arch (caller_frame);
|
||
caller_core_addr_type = builtin_type (caller_arch)->builtin_func_ptr;
|
||
val = dwarf2_evaluate_loc_desc (caller_core_addr_type, caller_frame,
|
||
dwarf_block->data, dwarf_block->size,
|
||
dwarf_block->per_cu);
|
||
/* DW_AT_GNU_call_site_target is a DWARF expression, not a DWARF
|
||
location. */
|
||
if (VALUE_LVAL (val) == lval_memory)
|
||
return value_address (val);
|
||
else
|
||
return value_as_address (val);
|
||
}
|
||
|
||
case FIELD_LOC_KIND_PHYSNAME:
|
||
{
|
||
const char *physname;
|
||
struct bound_minimal_symbol msym;
|
||
|
||
physname = FIELD_STATIC_PHYSNAME (call_site->target);
|
||
|
||
/* Handle both the mangled and demangled PHYSNAME. */
|
||
msym = lookup_minimal_symbol (physname, NULL, NULL);
|
||
if (msym.minsym == NULL)
|
||
{
|
||
msym = lookup_minimal_symbol_by_pc (call_site->pc - 1);
|
||
throw_error (NO_ENTRY_VALUE_ERROR,
|
||
_("Cannot find function \"%s\" for a call site target "
|
||
"at %s in %s"),
|
||
physname, paddress (call_site_gdbarch, call_site->pc),
|
||
(msym.minsym == NULL ? "???"
|
||
: MSYMBOL_PRINT_NAME (msym.minsym)));
|
||
|
||
}
|
||
return BMSYMBOL_VALUE_ADDRESS (msym);
|
||
}
|
||
|
||
case FIELD_LOC_KIND_PHYSADDR:
|
||
return FIELD_STATIC_PHYSADDR (call_site->target);
|
||
|
||
default:
|
||
internal_error (__FILE__, __LINE__, _("invalid call site target kind"));
|
||
}
|
||
}
|
||
|
||
/* Convert function entry point exact address ADDR to the function which is
|
||
compliant with TAIL_CALL_LIST_COMPLETE condition. Throw
|
||
NO_ENTRY_VALUE_ERROR otherwise. */
|
||
|
||
static struct symbol *
|
||
func_addr_to_tail_call_list (struct gdbarch *gdbarch, CORE_ADDR addr)
|
||
{
|
||
struct symbol *sym = find_pc_function (addr);
|
||
struct type *type;
|
||
|
||
if (sym == NULL || BLOCK_START (SYMBOL_BLOCK_VALUE (sym)) != addr)
|
||
throw_error (NO_ENTRY_VALUE_ERROR,
|
||
_("DW_TAG_GNU_call_site resolving failed to find function "
|
||
"name for address %s"),
|
||
paddress (gdbarch, addr));
|
||
|
||
type = SYMBOL_TYPE (sym);
|
||
gdb_assert (TYPE_CODE (type) == TYPE_CODE_FUNC);
|
||
gdb_assert (TYPE_SPECIFIC_FIELD (type) == TYPE_SPECIFIC_FUNC);
|
||
|
||
return sym;
|
||
}
|
||
|
||
/* Verify function with entry point exact address ADDR can never call itself
|
||
via its tail calls (incl. transitively). Throw NO_ENTRY_VALUE_ERROR if it
|
||
can call itself via tail calls.
|
||
|
||
If a funtion can tail call itself its entry value based parameters are
|
||
unreliable. There is no verification whether the value of some/all
|
||
parameters is unchanged through the self tail call, we expect if there is
|
||
a self tail call all the parameters can be modified. */
|
||
|
||
static void
|
||
func_verify_no_selftailcall (struct gdbarch *gdbarch, CORE_ADDR verify_addr)
|
||
{
|
||
struct obstack addr_obstack;
|
||
struct cleanup *old_chain;
|
||
CORE_ADDR addr;
|
||
|
||
/* Track here CORE_ADDRs which were already visited. */
|
||
htab_t addr_hash;
|
||
|
||
/* The verification is completely unordered. Track here function addresses
|
||
which still need to be iterated. */
|
||
VEC (CORE_ADDR) *todo = NULL;
|
||
|
||
obstack_init (&addr_obstack);
|
||
old_chain = make_cleanup_obstack_free (&addr_obstack);
|
||
addr_hash = htab_create_alloc_ex (64, core_addr_hash, core_addr_eq, NULL,
|
||
&addr_obstack, hashtab_obstack_allocate,
|
||
NULL);
|
||
make_cleanup_htab_delete (addr_hash);
|
||
|
||
make_cleanup (VEC_cleanup (CORE_ADDR), &todo);
|
||
|
||
VEC_safe_push (CORE_ADDR, todo, verify_addr);
|
||
while (!VEC_empty (CORE_ADDR, todo))
|
||
{
|
||
struct symbol *func_sym;
|
||
struct call_site *call_site;
|
||
|
||
addr = VEC_pop (CORE_ADDR, todo);
|
||
|
||
func_sym = func_addr_to_tail_call_list (gdbarch, addr);
|
||
|
||
for (call_site = TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (func_sym));
|
||
call_site; call_site = call_site->tail_call_next)
|
||
{
|
||
CORE_ADDR target_addr;
|
||
void **slot;
|
||
|
||
/* CALLER_FRAME with registers is not available for tail-call jumped
|
||
frames. */
|
||
target_addr = call_site_to_target_addr (gdbarch, call_site, NULL);
|
||
|
||
if (target_addr == verify_addr)
|
||
{
|
||
struct bound_minimal_symbol msym;
|
||
|
||
msym = lookup_minimal_symbol_by_pc (verify_addr);
|
||
throw_error (NO_ENTRY_VALUE_ERROR,
|
||
_("DW_OP_GNU_entry_value resolving has found "
|
||
"function \"%s\" at %s can call itself via tail "
|
||
"calls"),
|
||
(msym.minsym == NULL ? "???"
|
||
: MSYMBOL_PRINT_NAME (msym.minsym)),
|
||
paddress (gdbarch, verify_addr));
|
||
}
|
||
|
||
slot = htab_find_slot (addr_hash, &target_addr, INSERT);
|
||
if (*slot == NULL)
|
||
{
|
||
*slot = obstack_copy (&addr_obstack, &target_addr,
|
||
sizeof (target_addr));
|
||
VEC_safe_push (CORE_ADDR, todo, target_addr);
|
||
}
|
||
}
|
||
}
|
||
|
||
do_cleanups (old_chain);
|
||
}
|
||
|
||
/* Print user readable form of CALL_SITE->PC to gdb_stdlog. Used only for
|
||
ENTRY_VALUES_DEBUG. */
|
||
|
||
static void
|
||
tailcall_dump (struct gdbarch *gdbarch, const struct call_site *call_site)
|
||
{
|
||
CORE_ADDR addr = call_site->pc;
|
||
struct bound_minimal_symbol msym = lookup_minimal_symbol_by_pc (addr - 1);
|
||
|
||
fprintf_unfiltered (gdb_stdlog, " %s(%s)", paddress (gdbarch, addr),
|
||
(msym.minsym == NULL ? "???"
|
||
: MSYMBOL_PRINT_NAME (msym.minsym)));
|
||
|
||
}
|
||
|
||
/* vec.h needs single word type name, typedef it. */
|
||
typedef struct call_site *call_sitep;
|
||
|
||
/* Define VEC (call_sitep) functions. */
|
||
DEF_VEC_P (call_sitep);
|
||
|
||
/* Intersect RESULTP with CHAIN to keep RESULTP unambiguous, keep in RESULTP
|
||
only top callers and bottom callees which are present in both. GDBARCH is
|
||
used only for ENTRY_VALUES_DEBUG. RESULTP is NULL after return if there are
|
||
no remaining possibilities to provide unambiguous non-trivial result.
|
||
RESULTP should point to NULL on the first (initialization) call. Caller is
|
||
responsible for xfree of any RESULTP data. */
|
||
|
||
static void
|
||
chain_candidate (struct gdbarch *gdbarch, struct call_site_chain **resultp,
|
||
VEC (call_sitep) *chain)
|
||
{
|
||
struct call_site_chain *result = *resultp;
|
||
long length = VEC_length (call_sitep, chain);
|
||
int callers, callees, idx;
|
||
|
||
if (result == NULL)
|
||
{
|
||
/* Create the initial chain containing all the passed PCs. */
|
||
|
||
result = xmalloc (sizeof (*result) + sizeof (*result->call_site)
|
||
* (length - 1));
|
||
result->length = length;
|
||
result->callers = result->callees = length;
|
||
if (!VEC_empty (call_sitep, chain))
|
||
memcpy (result->call_site, VEC_address (call_sitep, chain),
|
||
sizeof (*result->call_site) * length);
|
||
*resultp = result;
|
||
|
||
if (entry_values_debug)
|
||
{
|
||
fprintf_unfiltered (gdb_stdlog, "tailcall: initial:");
|
||
for (idx = 0; idx < length; idx++)
|
||
tailcall_dump (gdbarch, result->call_site[idx]);
|
||
fputc_unfiltered ('\n', gdb_stdlog);
|
||
}
|
||
|
||
return;
|
||
}
|
||
|
||
if (entry_values_debug)
|
||
{
|
||
fprintf_unfiltered (gdb_stdlog, "tailcall: compare:");
|
||
for (idx = 0; idx < length; idx++)
|
||
tailcall_dump (gdbarch, VEC_index (call_sitep, chain, idx));
|
||
fputc_unfiltered ('\n', gdb_stdlog);
|
||
}
|
||
|
||
/* Intersect callers. */
|
||
|
||
callers = min (result->callers, length);
|
||
for (idx = 0; idx < callers; idx++)
|
||
if (result->call_site[idx] != VEC_index (call_sitep, chain, idx))
|
||
{
|
||
result->callers = idx;
|
||
break;
|
||
}
|
||
|
||
/* Intersect callees. */
|
||
|
||
callees = min (result->callees, length);
|
||
for (idx = 0; idx < callees; idx++)
|
||
if (result->call_site[result->length - 1 - idx]
|
||
!= VEC_index (call_sitep, chain, length - 1 - idx))
|
||
{
|
||
result->callees = idx;
|
||
break;
|
||
}
|
||
|
||
if (entry_values_debug)
|
||
{
|
||
fprintf_unfiltered (gdb_stdlog, "tailcall: reduced:");
|
||
for (idx = 0; idx < result->callers; idx++)
|
||
tailcall_dump (gdbarch, result->call_site[idx]);
|
||
fputs_unfiltered (" |", gdb_stdlog);
|
||
for (idx = 0; idx < result->callees; idx++)
|
||
tailcall_dump (gdbarch, result->call_site[result->length
|
||
- result->callees + idx]);
|
||
fputc_unfiltered ('\n', gdb_stdlog);
|
||
}
|
||
|
||
if (result->callers == 0 && result->callees == 0)
|
||
{
|
||
/* There are no common callers or callees. It could be also a direct
|
||
call (which has length 0) with ambiguous possibility of an indirect
|
||
call - CALLERS == CALLEES == 0 is valid during the first allocation
|
||
but any subsequence processing of such entry means ambiguity. */
|
||
xfree (result);
|
||
*resultp = NULL;
|
||
return;
|
||
}
|
||
|
||
/* See call_site_find_chain_1 why there is no way to reach the bottom callee
|
||
PC again. In such case there must be two different code paths to reach
|
||
it, therefore some of the former determined intermediate PCs must differ
|
||
and the unambiguous chain gets shortened. */
|
||
gdb_assert (result->callers + result->callees < result->length);
|
||
}
|
||
|
||
/* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the
|
||
assumed frames between them use GDBARCH. Use depth first search so we can
|
||
keep single CHAIN of call_site's back to CALLER_PC. Function recursion
|
||
would have needless GDB stack overhead. Caller is responsible for xfree of
|
||
the returned result. Any unreliability results in thrown
|
||
NO_ENTRY_VALUE_ERROR. */
|
||
|
||
static struct call_site_chain *
|
||
call_site_find_chain_1 (struct gdbarch *gdbarch, CORE_ADDR caller_pc,
|
||
CORE_ADDR callee_pc)
|
||
{
|
||
CORE_ADDR save_callee_pc = callee_pc;
|
||
struct obstack addr_obstack;
|
||
struct cleanup *back_to_retval, *back_to_workdata;
|
||
struct call_site_chain *retval = NULL;
|
||
struct call_site *call_site;
|
||
|
||
/* Mark CALL_SITEs so we do not visit the same ones twice. */
|
||
htab_t addr_hash;
|
||
|
||
/* CHAIN contains only the intermediate CALL_SITEs. Neither CALLER_PC's
|
||
call_site nor any possible call_site at CALLEE_PC's function is there.
|
||
Any CALL_SITE in CHAIN will be iterated to its siblings - via
|
||
TAIL_CALL_NEXT. This is inappropriate for CALLER_PC's call_site. */
|
||
VEC (call_sitep) *chain = NULL;
|
||
|
||
/* We are not interested in the specific PC inside the callee function. */
|
||
callee_pc = get_pc_function_start (callee_pc);
|
||
if (callee_pc == 0)
|
||
throw_error (NO_ENTRY_VALUE_ERROR, _("Unable to find function for PC %s"),
|
||
paddress (gdbarch, save_callee_pc));
|
||
|
||
back_to_retval = make_cleanup (free_current_contents, &retval);
|
||
|
||
obstack_init (&addr_obstack);
|
||
back_to_workdata = make_cleanup_obstack_free (&addr_obstack);
|
||
addr_hash = htab_create_alloc_ex (64, core_addr_hash, core_addr_eq, NULL,
|
||
&addr_obstack, hashtab_obstack_allocate,
|
||
NULL);
|
||
make_cleanup_htab_delete (addr_hash);
|
||
|
||
make_cleanup (VEC_cleanup (call_sitep), &chain);
|
||
|
||
/* Do not push CALL_SITE to CHAIN. Push there only the first tail call site
|
||
at the target's function. All the possible tail call sites in the
|
||
target's function will get iterated as already pushed into CHAIN via their
|
||
TAIL_CALL_NEXT. */
|
||
call_site = call_site_for_pc (gdbarch, caller_pc);
|
||
|
||
while (call_site)
|
||
{
|
||
CORE_ADDR target_func_addr;
|
||
struct call_site *target_call_site;
|
||
|
||
/* CALLER_FRAME with registers is not available for tail-call jumped
|
||
frames. */
|
||
target_func_addr = call_site_to_target_addr (gdbarch, call_site, NULL);
|
||
|
||
if (target_func_addr == callee_pc)
|
||
{
|
||
chain_candidate (gdbarch, &retval, chain);
|
||
if (retval == NULL)
|
||
break;
|
||
|
||
/* There is no way to reach CALLEE_PC again as we would prevent
|
||
entering it twice as being already marked in ADDR_HASH. */
|
||
target_call_site = NULL;
|
||
}
|
||
else
|
||
{
|
||
struct symbol *target_func;
|
||
|
||
target_func = func_addr_to_tail_call_list (gdbarch, target_func_addr);
|
||
target_call_site = TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (target_func));
|
||
}
|
||
|
||
do
|
||
{
|
||
/* Attempt to visit TARGET_CALL_SITE. */
|
||
|
||
if (target_call_site)
|
||
{
|
||
void **slot;
|
||
|
||
slot = htab_find_slot (addr_hash, &target_call_site->pc, INSERT);
|
||
if (*slot == NULL)
|
||
{
|
||
/* Successfully entered TARGET_CALL_SITE. */
|
||
|
||
*slot = &target_call_site->pc;
|
||
VEC_safe_push (call_sitep, chain, target_call_site);
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* Backtrack (without revisiting the originating call_site). Try the
|
||
callers's sibling; if there isn't any try the callers's callers's
|
||
sibling etc. */
|
||
|
||
target_call_site = NULL;
|
||
while (!VEC_empty (call_sitep, chain))
|
||
{
|
||
call_site = VEC_pop (call_sitep, chain);
|
||
|
||
gdb_assert (htab_find_slot (addr_hash, &call_site->pc,
|
||
NO_INSERT) != NULL);
|
||
htab_remove_elt (addr_hash, &call_site->pc);
|
||
|
||
target_call_site = call_site->tail_call_next;
|
||
if (target_call_site)
|
||
break;
|
||
}
|
||
}
|
||
while (target_call_site);
|
||
|
||
if (VEC_empty (call_sitep, chain))
|
||
call_site = NULL;
|
||
else
|
||
call_site = VEC_last (call_sitep, chain);
|
||
}
|
||
|
||
if (retval == NULL)
|
||
{
|
||
struct bound_minimal_symbol msym_caller, msym_callee;
|
||
|
||
msym_caller = lookup_minimal_symbol_by_pc (caller_pc);
|
||
msym_callee = lookup_minimal_symbol_by_pc (callee_pc);
|
||
throw_error (NO_ENTRY_VALUE_ERROR,
|
||
_("There are no unambiguously determinable intermediate "
|
||
"callers or callees between caller function \"%s\" at %s "
|
||
"and callee function \"%s\" at %s"),
|
||
(msym_caller.minsym == NULL
|
||
? "???" : MSYMBOL_PRINT_NAME (msym_caller.minsym)),
|
||
paddress (gdbarch, caller_pc),
|
||
(msym_callee.minsym == NULL
|
||
? "???" : MSYMBOL_PRINT_NAME (msym_callee.minsym)),
|
||
paddress (gdbarch, callee_pc));
|
||
}
|
||
|
||
do_cleanups (back_to_workdata);
|
||
discard_cleanups (back_to_retval);
|
||
return retval;
|
||
}
|
||
|
||
/* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the
|
||
assumed frames between them use GDBARCH. If valid call_site_chain cannot be
|
||
constructed return NULL. Caller is responsible for xfree of the returned
|
||
result. */
|
||
|
||
struct call_site_chain *
|
||
call_site_find_chain (struct gdbarch *gdbarch, CORE_ADDR caller_pc,
|
||
CORE_ADDR callee_pc)
|
||
{
|
||
volatile struct gdb_exception e;
|
||
struct call_site_chain *retval = NULL;
|
||
|
||
TRY_CATCH (e, RETURN_MASK_ERROR)
|
||
{
|
||
retval = call_site_find_chain_1 (gdbarch, caller_pc, callee_pc);
|
||
}
|
||
if (e.reason < 0)
|
||
{
|
||
if (e.error == NO_ENTRY_VALUE_ERROR)
|
||
{
|
||
if (entry_values_debug)
|
||
exception_print (gdb_stdout, e);
|
||
|
||
return NULL;
|
||
}
|
||
else
|
||
throw_exception (e);
|
||
}
|
||
return retval;
|
||
}
|
||
|
||
/* Return 1 if KIND and KIND_U match PARAMETER. Return 0 otherwise. */
|
||
|
||
static int
|
||
call_site_parameter_matches (struct call_site_parameter *parameter,
|
||
enum call_site_parameter_kind kind,
|
||
union call_site_parameter_u kind_u)
|
||
{
|
||
if (kind == parameter->kind)
|
||
switch (kind)
|
||
{
|
||
case CALL_SITE_PARAMETER_DWARF_REG:
|
||
return kind_u.dwarf_reg == parameter->u.dwarf_reg;
|
||
case CALL_SITE_PARAMETER_FB_OFFSET:
|
||
return kind_u.fb_offset == parameter->u.fb_offset;
|
||
case CALL_SITE_PARAMETER_PARAM_OFFSET:
|
||
return kind_u.param_offset.cu_off == parameter->u.param_offset.cu_off;
|
||
}
|
||
return 0;
|
||
}
|
||
|
||
/* Fetch call_site_parameter from caller matching KIND and KIND_U.
|
||
FRAME is for callee.
|
||
|
||
Function always returns non-NULL, it throws NO_ENTRY_VALUE_ERROR
|
||
otherwise. */
|
||
|
||
static struct call_site_parameter *
|
||
dwarf_expr_reg_to_entry_parameter (struct frame_info *frame,
|
||
enum call_site_parameter_kind kind,
|
||
union call_site_parameter_u kind_u,
|
||
struct dwarf2_per_cu_data **per_cu_return)
|
||
{
|
||
CORE_ADDR func_addr, caller_pc;
|
||
struct gdbarch *gdbarch;
|
||
struct frame_info *caller_frame;
|
||
struct call_site *call_site;
|
||
int iparams;
|
||
/* Initialize it just to avoid a GCC false warning. */
|
||
struct call_site_parameter *parameter = NULL;
|
||
CORE_ADDR target_addr;
|
||
|
||
while (get_frame_type (frame) == INLINE_FRAME)
|
||
{
|
||
frame = get_prev_frame (frame);
|
||
gdb_assert (frame != NULL);
|
||
}
|
||
|
||
func_addr = get_frame_func (frame);
|
||
gdbarch = get_frame_arch (frame);
|
||
caller_frame = get_prev_frame (frame);
|
||
if (gdbarch != frame_unwind_arch (frame))
|
||
{
|
||
struct bound_minimal_symbol msym
|
||
= lookup_minimal_symbol_by_pc (func_addr);
|
||
struct gdbarch *caller_gdbarch = frame_unwind_arch (frame);
|
||
|
||
throw_error (NO_ENTRY_VALUE_ERROR,
|
||
_("DW_OP_GNU_entry_value resolving callee gdbarch %s "
|
||
"(of %s (%s)) does not match caller gdbarch %s"),
|
||
gdbarch_bfd_arch_info (gdbarch)->printable_name,
|
||
paddress (gdbarch, func_addr),
|
||
(msym.minsym == NULL ? "???"
|
||
: MSYMBOL_PRINT_NAME (msym.minsym)),
|
||
gdbarch_bfd_arch_info (caller_gdbarch)->printable_name);
|
||
}
|
||
|
||
if (caller_frame == NULL)
|
||
{
|
||
struct bound_minimal_symbol msym
|
||
= lookup_minimal_symbol_by_pc (func_addr);
|
||
|
||
throw_error (NO_ENTRY_VALUE_ERROR, _("DW_OP_GNU_entry_value resolving "
|
||
"requires caller of %s (%s)"),
|
||
paddress (gdbarch, func_addr),
|
||
(msym.minsym == NULL ? "???"
|
||
: MSYMBOL_PRINT_NAME (msym.minsym)));
|
||
}
|
||
caller_pc = get_frame_pc (caller_frame);
|
||
call_site = call_site_for_pc (gdbarch, caller_pc);
|
||
|
||
target_addr = call_site_to_target_addr (gdbarch, call_site, caller_frame);
|
||
if (target_addr != func_addr)
|
||
{
|
||
struct minimal_symbol *target_msym, *func_msym;
|
||
|
||
target_msym = lookup_minimal_symbol_by_pc (target_addr).minsym;
|
||
func_msym = lookup_minimal_symbol_by_pc (func_addr).minsym;
|
||
throw_error (NO_ENTRY_VALUE_ERROR,
|
||
_("DW_OP_GNU_entry_value resolving expects callee %s at %s "
|
||
"but the called frame is for %s at %s"),
|
||
(target_msym == NULL ? "???"
|
||
: MSYMBOL_PRINT_NAME (target_msym)),
|
||
paddress (gdbarch, target_addr),
|
||
func_msym == NULL ? "???" : MSYMBOL_PRINT_NAME (func_msym),
|
||
paddress (gdbarch, func_addr));
|
||
}
|
||
|
||
/* No entry value based parameters would be reliable if this function can
|
||
call itself via tail calls. */
|
||
func_verify_no_selftailcall (gdbarch, func_addr);
|
||
|
||
for (iparams = 0; iparams < call_site->parameter_count; iparams++)
|
||
{
|
||
parameter = &call_site->parameter[iparams];
|
||
if (call_site_parameter_matches (parameter, kind, kind_u))
|
||
break;
|
||
}
|
||
if (iparams == call_site->parameter_count)
|
||
{
|
||
struct minimal_symbol *msym
|
||
= lookup_minimal_symbol_by_pc (caller_pc).minsym;
|
||
|
||
/* DW_TAG_GNU_call_site_parameter will be missing just if GCC could not
|
||
determine its value. */
|
||
throw_error (NO_ENTRY_VALUE_ERROR, _("Cannot find matching parameter "
|
||
"at DW_TAG_GNU_call_site %s at %s"),
|
||
paddress (gdbarch, caller_pc),
|
||
msym == NULL ? "???" : MSYMBOL_PRINT_NAME (msym));
|
||
}
|
||
|
||
*per_cu_return = call_site->per_cu;
|
||
return parameter;
|
||
}
|
||
|
||
/* Return value for PARAMETER matching DEREF_SIZE. If DEREF_SIZE is -1, return
|
||
the normal DW_AT_GNU_call_site_value block. Otherwise return the
|
||
DW_AT_GNU_call_site_data_value (dereferenced) block.
|
||
|
||
TYPE and CALLER_FRAME specify how to evaluate the DWARF block into returned
|
||
struct value.
|
||
|
||
Function always returns non-NULL, non-optimized out value. It throws
|
||
NO_ENTRY_VALUE_ERROR if it cannot resolve the value for any reason. */
|
||
|
||
static struct value *
|
||
dwarf_entry_parameter_to_value (struct call_site_parameter *parameter,
|
||
CORE_ADDR deref_size, struct type *type,
|
||
struct frame_info *caller_frame,
|
||
struct dwarf2_per_cu_data *per_cu)
|
||
{
|
||
const gdb_byte *data_src;
|
||
gdb_byte *data;
|
||
size_t size;
|
||
|
||
data_src = deref_size == -1 ? parameter->value : parameter->data_value;
|
||
size = deref_size == -1 ? parameter->value_size : parameter->data_value_size;
|
||
|
||
/* DEREF_SIZE size is not verified here. */
|
||
if (data_src == NULL)
|
||
throw_error (NO_ENTRY_VALUE_ERROR,
|
||
_("Cannot resolve DW_AT_GNU_call_site_data_value"));
|
||
|
||
/* DW_AT_GNU_call_site_value is a DWARF expression, not a DWARF
|
||
location. Postprocessing of DWARF_VALUE_MEMORY would lose the type from
|
||
DWARF block. */
|
||
data = alloca (size + 1);
|
||
memcpy (data, data_src, size);
|
||
data[size] = DW_OP_stack_value;
|
||
|
||
return dwarf2_evaluate_loc_desc (type, caller_frame, data, size + 1, per_cu);
|
||
}
|
||
|
||
/* Execute DWARF block of call_site_parameter which matches KIND and KIND_U.
|
||
Choose DEREF_SIZE value of that parameter. Search caller of the CTX's
|
||
frame. CTX must be of dwarf_expr_ctx_funcs kind.
|
||
|
||
The CTX caller can be from a different CU - per_cu_dwarf_call implementation
|
||
can be more simple as it does not support cross-CU DWARF executions. */
|
||
|
||
static void
|
||
dwarf_expr_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)
|
||
{
|
||
struct dwarf_expr_baton *debaton;
|
||
struct frame_info *frame, *caller_frame;
|
||
struct dwarf2_per_cu_data *caller_per_cu;
|
||
struct dwarf_expr_baton baton_local;
|
||
struct dwarf_expr_context saved_ctx;
|
||
struct call_site_parameter *parameter;
|
||
const gdb_byte *data_src;
|
||
size_t size;
|
||
|
||
gdb_assert (ctx->funcs == &dwarf_expr_ctx_funcs);
|
||
debaton = ctx->baton;
|
||
frame = debaton->frame;
|
||
caller_frame = get_prev_frame (frame);
|
||
|
||
parameter = dwarf_expr_reg_to_entry_parameter (frame, kind, kind_u,
|
||
&caller_per_cu);
|
||
data_src = deref_size == -1 ? parameter->value : parameter->data_value;
|
||
size = deref_size == -1 ? parameter->value_size : parameter->data_value_size;
|
||
|
||
/* DEREF_SIZE size is not verified here. */
|
||
if (data_src == NULL)
|
||
throw_error (NO_ENTRY_VALUE_ERROR,
|
||
_("Cannot resolve DW_AT_GNU_call_site_data_value"));
|
||
|
||
baton_local.frame = caller_frame;
|
||
baton_local.per_cu = caller_per_cu;
|
||
baton_local.obj_address = 0;
|
||
|
||
saved_ctx.gdbarch = ctx->gdbarch;
|
||
saved_ctx.addr_size = ctx->addr_size;
|
||
saved_ctx.offset = ctx->offset;
|
||
saved_ctx.baton = ctx->baton;
|
||
ctx->gdbarch = get_objfile_arch (dwarf2_per_cu_objfile (baton_local.per_cu));
|
||
ctx->addr_size = dwarf2_per_cu_addr_size (baton_local.per_cu);
|
||
ctx->offset = dwarf2_per_cu_text_offset (baton_local.per_cu);
|
||
ctx->baton = &baton_local;
|
||
|
||
dwarf_expr_eval (ctx, data_src, size);
|
||
|
||
ctx->gdbarch = saved_ctx.gdbarch;
|
||
ctx->addr_size = saved_ctx.addr_size;
|
||
ctx->offset = saved_ctx.offset;
|
||
ctx->baton = saved_ctx.baton;
|
||
}
|
||
|
||
/* Callback function for dwarf2_evaluate_loc_desc.
|
||
Fetch the address indexed by DW_OP_GNU_addr_index. */
|
||
|
||
static CORE_ADDR
|
||
dwarf_expr_get_addr_index (void *baton, unsigned int index)
|
||
{
|
||
struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton;
|
||
|
||
return dwarf2_read_addr_index (debaton->per_cu, index);
|
||
}
|
||
|
||
/* Callback function for get_object_address. Return the address of the VLA
|
||
object. */
|
||
|
||
static CORE_ADDR
|
||
dwarf_expr_get_obj_addr (void *baton)
|
||
{
|
||
struct dwarf_expr_baton *debaton = baton;
|
||
|
||
gdb_assert (debaton != NULL);
|
||
|
||
if (debaton->obj_address == 0)
|
||
error (_("Location address is not set."));
|
||
|
||
return debaton->obj_address;
|
||
}
|
||
|
||
/* VALUE must be of type lval_computed with entry_data_value_funcs. Perform
|
||
the indirect method on it, that is use its stored target value, the sole
|
||
purpose of entry_data_value_funcs.. */
|
||
|
||
static struct value *
|
||
entry_data_value_coerce_ref (const struct value *value)
|
||
{
|
||
struct type *checked_type = check_typedef (value_type (value));
|
||
struct value *target_val;
|
||
|
||
if (TYPE_CODE (checked_type) != TYPE_CODE_REF)
|
||
return NULL;
|
||
|
||
target_val = value_computed_closure (value);
|
||
value_incref (target_val);
|
||
return target_val;
|
||
}
|
||
|
||
/* Implement copy_closure. */
|
||
|
||
static void *
|
||
entry_data_value_copy_closure (const struct value *v)
|
||
{
|
||
struct value *target_val = value_computed_closure (v);
|
||
|
||
value_incref (target_val);
|
||
return target_val;
|
||
}
|
||
|
||
/* Implement free_closure. */
|
||
|
||
static void
|
||
entry_data_value_free_closure (struct value *v)
|
||
{
|
||
struct value *target_val = value_computed_closure (v);
|
||
|
||
value_free (target_val);
|
||
}
|
||
|
||
/* Vector for methods for an entry value reference where the referenced value
|
||
is stored in the caller. On the first dereference use
|
||
DW_AT_GNU_call_site_data_value in the caller. */
|
||
|
||
static const struct lval_funcs entry_data_value_funcs =
|
||
{
|
||
NULL, /* read */
|
||
NULL, /* write */
|
||
NULL, /* indirect */
|
||
entry_data_value_coerce_ref,
|
||
NULL, /* check_synthetic_pointer */
|
||
entry_data_value_copy_closure,
|
||
entry_data_value_free_closure
|
||
};
|
||
|
||
/* Read parameter of TYPE at (callee) FRAME's function entry. KIND and KIND_U
|
||
are used to match DW_AT_location at the caller's
|
||
DW_TAG_GNU_call_site_parameter.
|
||
|
||
Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it
|
||
cannot resolve the parameter for any reason. */
|
||
|
||
static struct value *
|
||
value_of_dwarf_reg_entry (struct type *type, struct frame_info *frame,
|
||
enum call_site_parameter_kind kind,
|
||
union call_site_parameter_u kind_u)
|
||
{
|
||
struct type *checked_type = check_typedef (type);
|
||
struct type *target_type = TYPE_TARGET_TYPE (checked_type);
|
||
struct frame_info *caller_frame = get_prev_frame (frame);
|
||
struct value *outer_val, *target_val, *val;
|
||
struct call_site_parameter *parameter;
|
||
struct dwarf2_per_cu_data *caller_per_cu;
|
||
|
||
parameter = dwarf_expr_reg_to_entry_parameter (frame, kind, kind_u,
|
||
&caller_per_cu);
|
||
|
||
outer_val = dwarf_entry_parameter_to_value (parameter, -1 /* deref_size */,
|
||
type, caller_frame,
|
||
caller_per_cu);
|
||
|
||
/* Check if DW_AT_GNU_call_site_data_value cannot be used. If it should be
|
||
used and it is not available do not fall back to OUTER_VAL - dereferencing
|
||
TYPE_CODE_REF with non-entry data value would give current value - not the
|
||
entry value. */
|
||
|
||
if (TYPE_CODE (checked_type) != TYPE_CODE_REF
|
||
|| TYPE_TARGET_TYPE (checked_type) == NULL)
|
||
return outer_val;
|
||
|
||
target_val = dwarf_entry_parameter_to_value (parameter,
|
||
TYPE_LENGTH (target_type),
|
||
target_type, caller_frame,
|
||
caller_per_cu);
|
||
|
||
release_value (target_val);
|
||
val = allocate_computed_value (type, &entry_data_value_funcs,
|
||
target_val /* closure */);
|
||
|
||
/* Copy the referencing pointer to the new computed value. */
|
||
memcpy (value_contents_raw (val), value_contents_raw (outer_val),
|
||
TYPE_LENGTH (checked_type));
|
||
set_value_lazy (val, 0);
|
||
|
||
return val;
|
||
}
|
||
|
||
/* Read parameter of TYPE at (callee) FRAME's function entry. DATA and
|
||
SIZE are DWARF block used to match DW_AT_location at the caller's
|
||
DW_TAG_GNU_call_site_parameter.
|
||
|
||
Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it
|
||
cannot resolve the parameter for any reason. */
|
||
|
||
static struct value *
|
||
value_of_dwarf_block_entry (struct type *type, struct frame_info *frame,
|
||
const gdb_byte *block, size_t block_len)
|
||
{
|
||
union call_site_parameter_u kind_u;
|
||
|
||
kind_u.dwarf_reg = dwarf_block_to_dwarf_reg (block, block + block_len);
|
||
if (kind_u.dwarf_reg != -1)
|
||
return value_of_dwarf_reg_entry (type, frame, CALL_SITE_PARAMETER_DWARF_REG,
|
||
kind_u);
|
||
|
||
if (dwarf_block_to_fb_offset (block, block + block_len, &kind_u.fb_offset))
|
||
return value_of_dwarf_reg_entry (type, frame, CALL_SITE_PARAMETER_FB_OFFSET,
|
||
kind_u);
|
||
|
||
/* This can normally happen - throw NO_ENTRY_VALUE_ERROR to get the message
|
||
suppressed during normal operation. The expression can be arbitrary if
|
||
there is no caller-callee entry value binding expected. */
|
||
throw_error (NO_ENTRY_VALUE_ERROR,
|
||
_("DWARF-2 expression error: DW_OP_GNU_entry_value is supported "
|
||
"only for single DW_OP_reg* or for DW_OP_fbreg(*)"));
|
||
}
|
||
|
||
struct piece_closure
|
||
{
|
||
/* Reference count. */
|
||
int refc;
|
||
|
||
/* The CU from which this closure's expression came. */
|
||
struct dwarf2_per_cu_data *per_cu;
|
||
|
||
/* 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 (struct dwarf2_per_cu_data *per_cu,
|
||
int n_pieces, struct dwarf_expr_piece *pieces,
|
||
int addr_size)
|
||
{
|
||
struct piece_closure *c = XCNEW (struct piece_closure);
|
||
int i;
|
||
|
||
c->refc = 1;
|
||
c->per_cu = per_cu;
|
||
c->n_pieces = n_pieces;
|
||
c->addr_size = addr_size;
|
||
c->pieces = XCNEWVEC (struct dwarf_expr_piece, n_pieces);
|
||
|
||
memcpy (c->pieces, pieces, n_pieces * sizeof (struct dwarf_expr_piece));
|
||
for (i = 0; i < n_pieces; ++i)
|
||
if (c->pieces[i].location == DWARF_VALUE_STACK)
|
||
value_incref (c->pieces[i].v.value);
|
||
|
||
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 + 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;
|
||
gdb_byte *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 (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;
|
||
}
|
||
if (this_size_bits > type_len - offset)
|
||
this_size_bits = type_len - offset;
|
||
|
||
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.regno);
|
||
|
||
if (gdb_regnum != -1)
|
||
{
|
||
int optim, unavail;
|
||
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 (!get_frame_register_bytes (frame, gdb_regnum, reg_offset,
|
||
this_size, buffer,
|
||
&optim, &unavail))
|
||
{
|
||
/* Just so garbage doesn't ever shine through. */
|
||
memset (buffer, 0, this_size);
|
||
|
||
if (optim)
|
||
mark_value_bits_optimized_out (v, offset, this_size_bits);
|
||
if (unavail)
|
||
mark_value_bits_unavailable (v, offset, this_size_bits);
|
||
}
|
||
}
|
||
else
|
||
{
|
||
error (_("Unable to access DWARF register number %s"),
|
||
paddress (arch, p->v.regno));
|
||
}
|
||
}
|
||
break;
|
||
|
||
case DWARF_VALUE_MEMORY:
|
||
read_value_memory (v, offset,
|
||
p->v.mem.in_stack_memory,
|
||
p->v.mem.addr + source_offset,
|
||
buffer, this_size);
|
||
break;
|
||
|
||
case DWARF_VALUE_STACK:
|
||
{
|
||
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
|
||
{
|
||
const gdb_byte *val_bytes = value_contents_all (p->v.value);
|
||
|
||
intermediate_buffer = val_bytes + source_offset;
|
||
}
|
||
}
|
||
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;
|
||
|
||
/* These bits show up as zeros -- but do not cause the value
|
||
to be considered optimized-out. */
|
||
case DWARF_VALUE_IMPLICIT_POINTER:
|
||
break;
|
||
|
||
case DWARF_VALUE_OPTIMIZED_OUT:
|
||
mark_value_bits_optimized_out (v, offset, this_size_bits);
|
||
break;
|
||
|
||
default:
|
||
internal_error (__FILE__, __LINE__, _("invalid location type"));
|
||
}
|
||
|
||
if (p->location != DWARF_VALUE_OPTIMIZED_OUT
|
||
&& p->location != DWARF_VALUE_IMPLICIT_POINTER)
|
||
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;
|
||
gdb_byte *buffer = NULL;
|
||
struct cleanup *cleanup;
|
||
int bits_big_endian
|
||
= gdbarch_bits_big_endian (get_type_arch (value_type (to)));
|
||
|
||
if (frame == NULL)
|
||
{
|
||
mark_value_bytes_optimized_out (to, 0, TYPE_LENGTH (value_type (to)));
|
||
return;
|
||
}
|
||
|
||
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
|
||
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.regno);
|
||
|
||
if (gdb_regnum != -1)
|
||
{
|
||
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 (need_bitwise)
|
||
{
|
||
int optim, unavail;
|
||
|
||
if (!get_frame_register_bytes (frame, gdb_regnum, reg_offset,
|
||
this_size, buffer,
|
||
&optim, &unavail))
|
||
{
|
||
if (optim)
|
||
throw_error (OPTIMIZED_OUT_ERROR,
|
||
_("Can't do read-modify-write to "
|
||
"update bitfield; containing word "
|
||
"has been optimized out"));
|
||
if (unavail)
|
||
throw_error (NOT_AVAILABLE_ERROR,
|
||
_("Can't do read-modify-write to update "
|
||
"bitfield; containing word "
|
||
"is unavailable"));
|
||
}
|
||
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.regno));
|
||
}
|
||
}
|
||
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:
|
||
mark_value_bytes_optimized_out (to, 0, TYPE_LENGTH (value_type (to)));
|
||
break;
|
||
}
|
||
offset += this_size_bits;
|
||
}
|
||
|
||
do_cleanups (cleanup);
|
||
}
|
||
|
||
/* An implementation of an lval_funcs method to see whether a value is
|
||
a synthetic pointer. */
|
||
|
||
static int
|
||
check_pieced_synthetic_pointer (const struct value *value, int bit_offset,
|
||
int bit_length)
|
||
{
|
||
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_IMPLICIT_POINTER)
|
||
return 0;
|
||
}
|
||
|
||
return 1;
|
||
}
|
||
|
||
/* A wrapper function for get_frame_address_in_block. */
|
||
|
||
static CORE_ADDR
|
||
get_frame_address_in_block_wrapper (void *baton)
|
||
{
|
||
return get_frame_address_in_block (baton);
|
||
}
|
||
|
||
/* An implementation of an lval_funcs method to indirect through a
|
||
pointer. This handles the synthetic pointer case when needed. */
|
||
|
||
static struct value *
|
||
indirect_pieced_value (struct value *value)
|
||
{
|
||
struct piece_closure *c
|
||
= (struct piece_closure *) value_computed_closure (value);
|
||
struct type *type;
|
||
struct frame_info *frame;
|
||
struct dwarf2_locexpr_baton baton;
|
||
int i, bit_offset, bit_length;
|
||
struct dwarf_expr_piece *piece = NULL;
|
||
LONGEST byte_offset;
|
||
|
||
type = check_typedef (value_type (value));
|
||
if (TYPE_CODE (type) != TYPE_CODE_PTR)
|
||
return NULL;
|
||
|
||
bit_length = 8 * TYPE_LENGTH (type);
|
||
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_IMPLICIT_POINTER)
|
||
return NULL;
|
||
|
||
if (bit_length != 0)
|
||
error (_("Invalid use of DW_OP_GNU_implicit_pointer"));
|
||
|
||
piece = p;
|
||
break;
|
||
}
|
||
|
||
frame = get_selected_frame (_("No frame selected."));
|
||
|
||
/* This is an offset requested by GDB, such as value subscripts.
|
||
However, due to how synthetic pointers are implemented, this is
|
||
always presented to us as a pointer type. This means we have to
|
||
sign-extend it manually as appropriate. */
|
||
byte_offset = value_as_address (value);
|
||
if (TYPE_LENGTH (value_type (value)) < sizeof (LONGEST))
|
||
byte_offset = gdb_sign_extend (byte_offset,
|
||
8 * TYPE_LENGTH (value_type (value)));
|
||
byte_offset += piece->v.ptr.offset;
|
||
|
||
gdb_assert (piece);
|
||
baton
|
||
= dwarf2_fetch_die_loc_sect_off (piece->v.ptr.die, c->per_cu,
|
||
get_frame_address_in_block_wrapper,
|
||
frame);
|
||
|
||
if (baton.data != NULL)
|
||
return dwarf2_evaluate_loc_desc_full (TYPE_TARGET_TYPE (type), frame,
|
||
baton.data, baton.size, baton.per_cu,
|
||
byte_offset);
|
||
|
||
{
|
||
struct obstack temp_obstack;
|
||
struct cleanup *cleanup;
|
||
const gdb_byte *bytes;
|
||
LONGEST len;
|
||
struct value *result;
|
||
|
||
obstack_init (&temp_obstack);
|
||
cleanup = make_cleanup_obstack_free (&temp_obstack);
|
||
|
||
bytes = dwarf2_fetch_constant_bytes (piece->v.ptr.die, c->per_cu,
|
||
&temp_obstack, &len);
|
||
if (bytes == NULL)
|
||
result = allocate_optimized_out_value (TYPE_TARGET_TYPE (type));
|
||
else
|
||
{
|
||
if (byte_offset < 0
|
||
|| byte_offset + TYPE_LENGTH (TYPE_TARGET_TYPE (type)) > len)
|
||
invalid_synthetic_pointer ();
|
||
bytes += byte_offset;
|
||
result = value_from_contents (TYPE_TARGET_TYPE (type), bytes);
|
||
}
|
||
|
||
do_cleanups (cleanup);
|
||
return result;
|
||
}
|
||
}
|
||
|
||
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;
|
||
}
|
||
|
||
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)
|
||
{
|
||
int i;
|
||
|
||
for (i = 0; i < c->n_pieces; ++i)
|
||
if (c->pieces[i].location == DWARF_VALUE_STACK)
|
||
value_free (c->pieces[i].v.value);
|
||
|
||
xfree (c->pieces);
|
||
xfree (c);
|
||
}
|
||
}
|
||
|
||
/* Functions for accessing a variable described by DW_OP_piece. */
|
||
static const struct lval_funcs pieced_value_funcs = {
|
||
read_pieced_value,
|
||
write_pieced_value,
|
||
indirect_pieced_value,
|
||
NULL, /* coerce_ref */
|
||
check_pieced_synthetic_pointer,
|
||
copy_pieced_value_closure,
|
||
free_pieced_value_closure
|
||
};
|
||
|
||
/* Virtual method table for dwarf2_evaluate_loc_desc_full below. */
|
||
|
||
static const struct dwarf_expr_context_funcs dwarf_expr_ctx_funcs =
|
||
{
|
||
dwarf_expr_read_addr_from_reg,
|
||
dwarf_expr_get_reg_value,
|
||
dwarf_expr_read_mem,
|
||
dwarf_expr_frame_base,
|
||
dwarf_expr_frame_cfa,
|
||
dwarf_expr_frame_pc,
|
||
dwarf_expr_tls_address,
|
||
dwarf_expr_dwarf_call,
|
||
dwarf_expr_get_base_type,
|
||
dwarf_expr_push_dwarf_reg_entry_value,
|
||
dwarf_expr_get_addr_index,
|
||
dwarf_expr_get_obj_addr
|
||
};
|
||
|
||
/* Evaluate a location description, starting at DATA and with length
|
||
SIZE, to find the current location of variable of TYPE in the
|
||
context of FRAME. BYTE_OFFSET is applied after the contents are
|
||
computed. */
|
||
|
||
static struct value *
|
||
dwarf2_evaluate_loc_desc_full (struct type *type, struct frame_info *frame,
|
||
const gdb_byte *data, size_t size,
|
||
struct dwarf2_per_cu_data *per_cu,
|
||
LONGEST byte_offset)
|
||
{
|
||
struct value *retval;
|
||
struct dwarf_expr_baton baton;
|
||
struct dwarf_expr_context *ctx;
|
||
struct cleanup *old_chain, *value_chain;
|
||
struct objfile *objfile = dwarf2_per_cu_objfile (per_cu);
|
||
volatile struct gdb_exception ex;
|
||
|
||
if (byte_offset < 0)
|
||
invalid_synthetic_pointer ();
|
||
|
||
if (size == 0)
|
||
return allocate_optimized_out_value (type);
|
||
|
||
baton.frame = frame;
|
||
baton.per_cu = per_cu;
|
||
baton.obj_address = 0;
|
||
|
||
ctx = new_dwarf_expr_context ();
|
||
old_chain = make_cleanup_free_dwarf_expr_context (ctx);
|
||
value_chain = make_cleanup_value_free_to_mark (value_mark ());
|
||
|
||
ctx->gdbarch = get_objfile_arch (objfile);
|
||
ctx->addr_size = dwarf2_per_cu_addr_size (per_cu);
|
||
ctx->ref_addr_size = dwarf2_per_cu_ref_addr_size (per_cu);
|
||
ctx->offset = dwarf2_per_cu_text_offset (per_cu);
|
||
ctx->baton = &baton;
|
||
ctx->funcs = &dwarf_expr_ctx_funcs;
|
||
|
||
TRY_CATCH (ex, RETURN_MASK_ERROR)
|
||
{
|
||
dwarf_expr_eval (ctx, data, size);
|
||
}
|
||
if (ex.reason < 0)
|
||
{
|
||
if (ex.error == NOT_AVAILABLE_ERROR)
|
||
{
|
||
do_cleanups (old_chain);
|
||
retval = allocate_value (type);
|
||
mark_value_bytes_unavailable (retval, 0, TYPE_LENGTH (type));
|
||
return retval;
|
||
}
|
||
else if (ex.error == NO_ENTRY_VALUE_ERROR)
|
||
{
|
||
if (entry_values_debug)
|
||
exception_print (gdb_stdout, ex);
|
||
do_cleanups (old_chain);
|
||
return allocate_optimized_out_value (type);
|
||
}
|
||
else
|
||
throw_exception (ex);
|
||
}
|
||
|
||
if (ctx->num_pieces > 0)
|
||
{
|
||
struct piece_closure *c;
|
||
struct frame_id frame_id = get_frame_id (frame);
|
||
ULONGEST bit_size = 0;
|
||
int i;
|
||
|
||
for (i = 0; i < ctx->num_pieces; ++i)
|
||
bit_size += ctx->pieces[i].size;
|
||
if (8 * (byte_offset + TYPE_LENGTH (type)) > bit_size)
|
||
invalid_synthetic_pointer ();
|
||
|
||
c = allocate_piece_closure (per_cu, ctx->num_pieces, ctx->pieces,
|
||
ctx->addr_size);
|
||
/* We must clean up the value chain after creating the piece
|
||
closure but before allocating the result. */
|
||
do_cleanups (value_chain);
|
||
retval = allocate_computed_value (type, &pieced_value_funcs, c);
|
||
VALUE_FRAME_ID (retval) = frame_id;
|
||
set_value_offset (retval, byte_offset);
|
||
}
|
||
else
|
||
{
|
||
switch (ctx->location)
|
||
{
|
||
case DWARF_VALUE_REGISTER:
|
||
{
|
||
struct gdbarch *arch = get_frame_arch (frame);
|
||
int dwarf_regnum
|
||
= longest_to_int (value_as_long (dwarf_expr_fetch (ctx, 0)));
|
||
int gdb_regnum = gdbarch_dwarf2_reg_to_regnum (arch, dwarf_regnum);
|
||
|
||
if (byte_offset != 0)
|
||
error (_("cannot use offset on synthetic pointer to register"));
|
||
do_cleanups (value_chain);
|
||
if (gdb_regnum == -1)
|
||
error (_("Unable to access DWARF register number %d"),
|
||
dwarf_regnum);
|
||
retval = value_from_register (type, gdb_regnum, frame);
|
||
if (value_optimized_out (retval))
|
||
{
|
||
struct value *tmp;
|
||
|
||
/* This means the register has undefined value / was
|
||
not saved. As we're computing the location of some
|
||
variable etc. in the program, not a value for
|
||
inspecting a register ($pc, $sp, etc.), return a
|
||
generic optimized out value instead, so that we show
|
||
<optimized out> instead of <not saved>. */
|
||
do_cleanups (value_chain);
|
||
tmp = allocate_value (type);
|
||
value_contents_copy (tmp, 0, retval, 0, TYPE_LENGTH (type));
|
||
retval = tmp;
|
||
}
|
||
}
|
||
break;
|
||
|
||
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);
|
||
|
||
do_cleanups (value_chain);
|
||
retval = value_at_lazy (type, address + byte_offset);
|
||
if (in_stack_memory)
|
||
set_value_stack (retval, 1);
|
||
}
|
||
break;
|
||
|
||
case DWARF_VALUE_STACK:
|
||
{
|
||
struct value *value = dwarf_expr_fetch (ctx, 0);
|
||
gdb_byte *contents;
|
||
const gdb_byte *val_bytes;
|
||
size_t n = TYPE_LENGTH (value_type (value));
|
||
|
||
if (byte_offset + TYPE_LENGTH (type) > n)
|
||
invalid_synthetic_pointer ();
|
||
|
||
val_bytes = value_contents_all (value);
|
||
val_bytes += byte_offset;
|
||
n -= byte_offset;
|
||
|
||
/* Preserve VALUE because we are going to free values back
|
||
to the mark, but we still need the value contents
|
||
below. */
|
||
value_incref (value);
|
||
do_cleanups (value_chain);
|
||
make_cleanup_value_free (value);
|
||
|
||
retval = allocate_value (type);
|
||
contents = value_contents_raw (retval);
|
||
if (n > TYPE_LENGTH (type))
|
||
{
|
||
struct gdbarch *objfile_gdbarch = get_objfile_arch (objfile);
|
||
|
||
if (gdbarch_byte_order (objfile_gdbarch) == BFD_ENDIAN_BIG)
|
||
val_bytes += n - TYPE_LENGTH (type);
|
||
n = TYPE_LENGTH (type);
|
||
}
|
||
memcpy (contents, val_bytes, n);
|
||
}
|
||
break;
|
||
|
||
case DWARF_VALUE_LITERAL:
|
||
{
|
||
bfd_byte *contents;
|
||
const bfd_byte *ldata;
|
||
size_t n = ctx->len;
|
||
|
||
if (byte_offset + TYPE_LENGTH (type) > n)
|
||
invalid_synthetic_pointer ();
|
||
|
||
do_cleanups (value_chain);
|
||
retval = allocate_value (type);
|
||
contents = value_contents_raw (retval);
|
||
|
||
ldata = ctx->data + byte_offset;
|
||
n -= byte_offset;
|
||
|
||
if (n > TYPE_LENGTH (type))
|
||
{
|
||
struct gdbarch *objfile_gdbarch = get_objfile_arch (objfile);
|
||
|
||
if (gdbarch_byte_order (objfile_gdbarch) == BFD_ENDIAN_BIG)
|
||
ldata += n - TYPE_LENGTH (type);
|
||
n = TYPE_LENGTH (type);
|
||
}
|
||
memcpy (contents, ldata, n);
|
||
}
|
||
break;
|
||
|
||
case DWARF_VALUE_OPTIMIZED_OUT:
|
||
do_cleanups (value_chain);
|
||
retval = allocate_optimized_out_value (type);
|
||
break;
|
||
|
||
/* DWARF_VALUE_IMPLICIT_POINTER was converted to a pieced
|
||
operation by execute_stack_op. */
|
||
case DWARF_VALUE_IMPLICIT_POINTER:
|
||
/* DWARF_VALUE_OPTIMIZED_OUT can't occur in this context --
|
||
it can only be encountered when making a piece. */
|
||
default:
|
||
internal_error (__FILE__, __LINE__, _("invalid location type"));
|
||
}
|
||
}
|
||
|
||
set_value_initialized (retval, ctx->initialized);
|
||
|
||
do_cleanups (old_chain);
|
||
|
||
return retval;
|
||
}
|
||
|
||
/* The exported interface to dwarf2_evaluate_loc_desc_full; it always
|
||
passes 0 as the byte_offset. */
|
||
|
||
struct value *
|
||
dwarf2_evaluate_loc_desc (struct type *type, struct frame_info *frame,
|
||
const gdb_byte *data, size_t size,
|
||
struct dwarf2_per_cu_data *per_cu)
|
||
{
|
||
return dwarf2_evaluate_loc_desc_full (type, frame, data, size, per_cu, 0);
|
||
}
|
||
|
||
/* Evaluates a dwarf expression and stores the result in VAL, expecting
|
||
that the dwarf expression only produces a single CORE_ADDR. ADDR is a
|
||
context (location of a variable) and might be needed to evaluate the
|
||
location expression.
|
||
Returns 1 on success, 0 otherwise. */
|
||
|
||
static int
|
||
dwarf2_locexpr_baton_eval (const struct dwarf2_locexpr_baton *dlbaton,
|
||
CORE_ADDR addr,
|
||
CORE_ADDR *valp)
|
||
{
|
||
struct dwarf_expr_context *ctx;
|
||
struct dwarf_expr_baton baton;
|
||
struct objfile *objfile;
|
||
struct cleanup *cleanup;
|
||
|
||
if (dlbaton == NULL || dlbaton->size == 0)
|
||
return 0;
|
||
|
||
ctx = new_dwarf_expr_context ();
|
||
cleanup = make_cleanup_free_dwarf_expr_context (ctx);
|
||
|
||
baton.frame = get_selected_frame (NULL);
|
||
baton.per_cu = dlbaton->per_cu;
|
||
baton.obj_address = addr;
|
||
|
||
objfile = dwarf2_per_cu_objfile (dlbaton->per_cu);
|
||
|
||
ctx->gdbarch = get_objfile_arch (objfile);
|
||
ctx->addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu);
|
||
ctx->ref_addr_size = dwarf2_per_cu_ref_addr_size (dlbaton->per_cu);
|
||
ctx->offset = dwarf2_per_cu_text_offset (dlbaton->per_cu);
|
||
ctx->funcs = &dwarf_expr_ctx_funcs;
|
||
ctx->baton = &baton;
|
||
|
||
dwarf_expr_eval (ctx, dlbaton->data, dlbaton->size);
|
||
|
||
switch (ctx->location)
|
||
{
|
||
case DWARF_VALUE_REGISTER:
|
||
case DWARF_VALUE_MEMORY:
|
||
case DWARF_VALUE_STACK:
|
||
*valp = dwarf_expr_fetch_address (ctx, 0);
|
||
if (ctx->location == DWARF_VALUE_REGISTER)
|
||
*valp = dwarf_expr_read_addr_from_reg (&baton, *valp);
|
||
do_cleanups (cleanup);
|
||
return 1;
|
||
case DWARF_VALUE_LITERAL:
|
||
*valp = extract_signed_integer (ctx->data, ctx->len,
|
||
gdbarch_byte_order (ctx->gdbarch));
|
||
do_cleanups (cleanup);
|
||
return 1;
|
||
/* Unsupported dwarf values. */
|
||
case DWARF_VALUE_OPTIMIZED_OUT:
|
||
case DWARF_VALUE_IMPLICIT_POINTER:
|
||
break;
|
||
}
|
||
|
||
do_cleanups (cleanup);
|
||
return 0;
|
||
}
|
||
|
||
/* See dwarf2loc.h. */
|
||
|
||
int
|
||
dwarf2_evaluate_property (const struct dynamic_prop *prop,
|
||
CORE_ADDR address, CORE_ADDR *value)
|
||
{
|
||
if (prop == NULL)
|
||
return 0;
|
||
|
||
switch (prop->kind)
|
||
{
|
||
case PROP_LOCEXPR:
|
||
{
|
||
const struct dwarf2_property_baton *baton = prop->data.baton;
|
||
|
||
if (dwarf2_locexpr_baton_eval (&baton->locexpr, address, value))
|
||
{
|
||
if (baton->referenced_type)
|
||
{
|
||
struct value *val = value_at (baton->referenced_type, *value);
|
||
|
||
*value = value_as_address (val);
|
||
}
|
||
return 1;
|
||
}
|
||
}
|
||
break;
|
||
|
||
case PROP_LOCLIST:
|
||
{
|
||
struct dwarf2_property_baton *baton = prop->data.baton;
|
||
struct frame_info *frame = get_selected_frame (NULL);
|
||
CORE_ADDR pc = get_frame_address_in_block (frame);
|
||
const gdb_byte *data;
|
||
struct value *val;
|
||
size_t size;
|
||
|
||
data = dwarf2_find_location_expression (&baton->loclist, &size, pc);
|
||
if (data != NULL)
|
||
{
|
||
val = dwarf2_evaluate_loc_desc (baton->referenced_type, frame, data,
|
||
size, baton->loclist.per_cu);
|
||
if (!value_optimized_out (val))
|
||
{
|
||
*value = value_as_address (val);
|
||
return 1;
|
||
}
|
||
}
|
||
}
|
||
break;
|
||
|
||
case PROP_CONST:
|
||
*value = prop->data.const_val;
|
||
return 1;
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* See dwarf2loc.h. */
|
||
|
||
void
|
||
dwarf2_compile_property_to_c (struct ui_file *stream,
|
||
const char *result_name,
|
||
struct gdbarch *gdbarch,
|
||
unsigned char *registers_used,
|
||
const struct dynamic_prop *prop,
|
||
CORE_ADDR pc,
|
||
struct symbol *sym)
|
||
{
|
||
struct dwarf2_property_baton *baton = prop->data.baton;
|
||
const gdb_byte *data;
|
||
size_t size;
|
||
struct dwarf2_per_cu_data *per_cu;
|
||
|
||
if (prop->kind == PROP_LOCEXPR)
|
||
{
|
||
data = baton->locexpr.data;
|
||
size = baton->locexpr.size;
|
||
per_cu = baton->locexpr.per_cu;
|
||
}
|
||
else
|
||
{
|
||
gdb_assert (prop->kind == PROP_LOCLIST);
|
||
|
||
data = dwarf2_find_location_expression (&baton->loclist, &size, pc);
|
||
per_cu = baton->loclist.per_cu;
|
||
}
|
||
|
||
compile_dwarf_bounds_to_c (stream, result_name, prop, sym, pc,
|
||
gdbarch, registers_used,
|
||
dwarf2_per_cu_addr_size (per_cu),
|
||
data, data + size, per_cu);
|
||
}
|
||
|
||
|
||
/* 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_addr_from_reg (void *baton, int regnum)
|
||
{
|
||
struct needs_frame_baton *nf_baton = baton;
|
||
|
||
nf_baton->needs_frame = 1;
|
||
return 1;
|
||
}
|
||
|
||
/* struct dwarf_expr_context_funcs' "get_reg_value" callback:
|
||
Reads from registers do require a frame. */
|
||
|
||
static struct value *
|
||
needs_frame_get_reg_value (void *baton, struct type *type, int regnum)
|
||
{
|
||
struct needs_frame_baton *nf_baton = baton;
|
||
|
||
nf_baton->needs_frame = 1;
|
||
return value_zero (type, not_lval);
|
||
}
|
||
|
||
/* Reads from memory do not require a frame. */
|
||
static void
|
||
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, const gdb_byte **start, size_t * length)
|
||
{
|
||
static gdb_byte lit0 = DW_OP_lit0;
|
||
struct needs_frame_baton *nf_baton = baton;
|
||
|
||
*start = &lit0;
|
||
*length = 1;
|
||
|
||
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, cu_offset die_offset)
|
||
{
|
||
struct needs_frame_baton *nf_baton = ctx->baton;
|
||
|
||
per_cu_dwarf_call (ctx, die_offset, nf_baton->per_cu,
|
||
ctx->funcs->get_frame_pc, ctx->baton);
|
||
}
|
||
|
||
/* DW_OP_GNU_entry_value accesses require a caller, therefore a frame. */
|
||
|
||
static void
|
||
needs_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)
|
||
{
|
||
struct needs_frame_baton *nf_baton = ctx->baton;
|
||
|
||
nf_baton->needs_frame = 1;
|
||
|
||
/* The expression may require some stub values on DWARF stack. */
|
||
dwarf_expr_push_address (ctx, 0, 0);
|
||
}
|
||
|
||
/* DW_OP_GNU_addr_index doesn't require a frame. */
|
||
|
||
static CORE_ADDR
|
||
needs_get_addr_index (void *baton, unsigned int index)
|
||
{
|
||
/* Nothing to do. */
|
||
return 1;
|
||
}
|
||
|
||
/* DW_OP_push_object_address has a frame already passed through. */
|
||
|
||
static CORE_ADDR
|
||
needs_get_obj_addr (void *baton)
|
||
{
|
||
/* Nothing to do. */
|
||
return 1;
|
||
}
|
||
|
||
/* Virtual method table for dwarf2_loc_desc_needs_frame below. */
|
||
|
||
static const struct dwarf_expr_context_funcs needs_frame_ctx_funcs =
|
||
{
|
||
needs_frame_read_addr_from_reg,
|
||
needs_frame_get_reg_value,
|
||
needs_frame_read_mem,
|
||
needs_frame_frame_base,
|
||
needs_frame_frame_cfa,
|
||
needs_frame_frame_cfa, /* get_frame_pc */
|
||
needs_frame_tls_address,
|
||
needs_frame_dwarf_call,
|
||
NULL, /* get_base_type */
|
||
needs_dwarf_reg_entry_value,
|
||
needs_get_addr_index,
|
||
needs_get_obj_addr
|
||
};
|
||
|
||
/* Return non-zero iff the location expression at DATA (length SIZE)
|
||
requires a frame to evaluate. */
|
||
|
||
static int
|
||
dwarf2_loc_desc_needs_frame (const gdb_byte *data, size_t 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);
|
||
make_cleanup_value_free_to_mark (value_mark ());
|
||
|
||
ctx->gdbarch = get_objfile_arch (objfile);
|
||
ctx->addr_size = dwarf2_per_cu_addr_size (per_cu);
|
||
ctx->ref_addr_size = dwarf2_per_cu_ref_addr_size (per_cu);
|
||
ctx->offset = dwarf2_per_cu_text_offset (per_cu);
|
||
ctx->baton = &baton;
|
||
ctx->funcs = &needs_frame_ctx_funcs;
|
||
|
||
dwarf_expr_eval (ctx, data, size);
|
||
|
||
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 || in_reg;
|
||
}
|
||
|
||
/* A helper function that throws an unimplemented error mentioning a
|
||
given DWARF operator. */
|
||
|
||
static void
|
||
unimplemented (unsigned int op)
|
||
{
|
||
const char *name = get_DW_OP_name (op);
|
||
|
||
if (name)
|
||
error (_("DWARF operator %s cannot be translated to an agent expression"),
|
||
name);
|
||
else
|
||
error (_("Unknown DWARF operator 0x%02x cannot be translated "
|
||
"to an agent expression"),
|
||
op);
|
||
}
|
||
|
||
/* See dwarf2loc.h. */
|
||
|
||
int
|
||
dwarf2_reg_to_regnum_or_error (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 (nbytes > 0 && nbytes <= sizeof (LONGEST));
|
||
|
||
if (expr->tracing)
|
||
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);
|
||
}
|
||
}
|
||
|
||
/* A helper function to return the frame's PC. */
|
||
|
||
static CORE_ADDR
|
||
get_ax_pc (void *baton)
|
||
{
|
||
struct agent_expr *expr = baton;
|
||
|
||
return expr->scope;
|
||
}
|
||
|
||
/* 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. */
|
||
|
||
void
|
||
dwarf2_compile_expr_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;
|
||
uint64_t uoffset, reg;
|
||
int64_t 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 = safe_read_uleb128 (op_ptr, op_end, &uoffset);
|
||
ax_const_l (expr, uoffset);
|
||
break;
|
||
case DW_OP_consts:
|
||
op_ptr = safe_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 = dwarf2_reg_to_regnum_or_error (arch, op - DW_OP_reg0);
|
||
loc->kind = axs_lvalue_register;
|
||
break;
|
||
|
||
case DW_OP_regx:
|
||
op_ptr = safe_read_uleb128 (op_ptr, op_end, ®);
|
||
dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_regx");
|
||
loc->u.reg = dwarf2_reg_to_regnum_or_error (arch, reg);
|
||
loc->kind = axs_lvalue_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."));
|
||
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 = safe_read_sleb128 (op_ptr, op_end, &offset);
|
||
i = dwarf2_reg_to_regnum_or_error (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 = safe_read_uleb128 (op_ptr, op_end, ®);
|
||
op_ptr = safe_read_sleb128 (op_ptr, op_end, &offset);
|
||
i = dwarf2_reg_to_regnum_or_error (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;
|
||
const struct block *b;
|
||
struct symbol *framefunc;
|
||
|
||
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"));
|
||
|
||
func_get_frame_base_dwarf_block (framefunc, expr->scope,
|
||
&datastart, &datalen);
|
||
|
||
op_ptr = safe_read_sleb128 (op_ptr, op_end, &offset);
|
||
dwarf2_compile_expr_to_ax (expr, loc, arch, addr_size, datastart,
|
||
datastart + datalen, per_cu);
|
||
if (loc->kind == axs_lvalue_register)
|
||
require_rvalue (expr, loc);
|
||
|
||
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++;
|
||
ax_pick (expr, offset);
|
||
break;
|
||
|
||
case DW_OP_swap:
|
||
ax_simple (expr, aop_swap);
|
||
break;
|
||
|
||
case DW_OP_over:
|
||
ax_pick (expr, 1);
|
||
break;
|
||
|
||
case DW_OP_rot:
|
||
ax_simple (expr, aop_rot);
|
||
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;
|
||
|
||
if (size != 1 && size != 2 && size != 4 && size != 8)
|
||
error (_("Unsupported size %d in %s"),
|
||
size, get_DW_OP_name (op));
|
||
access_memory (arch, expr, size * TARGET_CHAR_BIT);
|
||
}
|
||
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 = safe_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:
|
||
{
|
||
int regnum;
|
||
CORE_ADDR text_offset;
|
||
LONGEST off;
|
||
const gdb_byte *cfa_start, *cfa_end;
|
||
|
||
if (dwarf2_fetch_cfa_info (arch, expr->scope, per_cu,
|
||
®num, &off,
|
||
&text_offset, &cfa_start, &cfa_end))
|
||
{
|
||
/* Register. */
|
||
ax_reg (expr, regnum);
|
||
if (off != 0)
|
||
{
|
||
ax_const_l (expr, off);
|
||
ax_simple (expr, aop_add);
|
||
}
|
||
}
|
||
else
|
||
{
|
||
/* Another expression. */
|
||
ax_const_l (expr, text_offset);
|
||
dwarf2_compile_expr_to_ax (expr, loc, arch, addr_size,
|
||
cfa_start, cfa_end, per_cu);
|
||
}
|
||
|
||
loc->kind = axs_lvalue_memory;
|
||
}
|
||
break;
|
||
|
||
case DW_OP_GNU_push_tls_address:
|
||
unimplemented (op);
|
||
break;
|
||
|
||
case DW_OP_push_object_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:
|
||
{
|
||
uint64_t size, offset;
|
||
|
||
if (op_ptr - 1 == previous_piece)
|
||
error (_("Cannot translate empty pieces to agent expressions"));
|
||
previous_piece = op_ptr - 1;
|
||
|
||
op_ptr = safe_read_uleb128 (op_ptr, op_end, &size);
|
||
if (op == DW_OP_piece)
|
||
{
|
||
size *= 8;
|
||
offset = 0;
|
||
}
|
||
else
|
||
op_ptr = safe_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);
|
||
cu_offset offset;
|
||
|
||
uoffset = extract_unsigned_integer (op_ptr, size, byte_order);
|
||
op_ptr += size;
|
||
|
||
offset.cu_off = uoffset;
|
||
block = dwarf2_fetch_die_loc_cu_off (offset, per_cu,
|
||
get_ax_pc, expr);
|
||
|
||
/* DW_OP_call_ref is currently not supported. */
|
||
gdb_assert (block.per_cu == per_cu);
|
||
|
||
dwarf2_compile_expr_to_ax (expr, loc, arch, addr_size,
|
||
block.data, block.data + block.size,
|
||
per_cu);
|
||
}
|
||
break;
|
||
|
||
case DW_OP_call_ref:
|
||
unimplemented (op);
|
||
|
||
default:
|
||
unimplemented (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);
|
||
}
|
||
|
||
|
||
/* 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_TYPE (symbol), frame, dlbaton->data,
|
||
dlbaton->size, dlbaton->per_cu);
|
||
|
||
return val;
|
||
}
|
||
|
||
/* Return the value of SYMBOL in FRAME at (callee) FRAME's function
|
||
entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
|
||
will be thrown. */
|
||
|
||
static struct value *
|
||
locexpr_read_variable_at_entry (struct symbol *symbol, struct frame_info *frame)
|
||
{
|
||
struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol);
|
||
|
||
return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol), frame, dlbaton->data,
|
||
dlbaton->size);
|
||
}
|
||
|
||
/* Return non-zero iff we need a frame to evaluate SYMBOL. */
|
||
static int
|
||
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,
|
||
dlbaton->per_cu);
|
||
}
|
||
|
||
/* Return true if DATA points to the end of a piece. END is one past
|
||
the last byte in the expression. */
|
||
|
||
static int
|
||
piece_end_p (const gdb_byte *data, const gdb_byte *end)
|
||
{
|
||
return data == end || data[0] == DW_OP_piece || data[0] == DW_OP_bit_piece;
|
||
}
|
||
|
||
/* Helper for locexpr_describe_location_piece that finds the name of a
|
||
DWARF register. */
|
||
|
||
static const char *
|
||
locexpr_regname (struct gdbarch *gdbarch, int dwarf_regnum)
|
||
{
|
||
int regnum;
|
||
|
||
regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, dwarf_regnum);
|
||
return gdbarch_register_name (gdbarch, regnum);
|
||
}
|
||
|
||
/* 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. If there is an error during reading, e.g. we run off the end
|
||
of the buffer, an error is thrown. */
|
||
|
||
static const gdb_byte *
|
||
locexpr_describe_location_piece (struct symbol *symbol, struct ui_file *stream,
|
||
CORE_ADDR addr, struct objfile *objfile,
|
||
struct dwarf2_per_cu_data *per_cu,
|
||
const gdb_byte *data, const gdb_byte *end,
|
||
unsigned int addr_size)
|
||
{
|
||
struct gdbarch *gdbarch = get_objfile_arch (objfile);
|
||
size_t leb128_size;
|
||
|
||
if (data[0] >= DW_OP_reg0 && data[0] <= DW_OP_reg31)
|
||
{
|
||
fprintf_filtered (stream, _("a variable in $%s"),
|
||
locexpr_regname (gdbarch, data[0] - DW_OP_reg0));
|
||
data += 1;
|
||
}
|
||
else if (data[0] == DW_OP_regx)
|
||
{
|
||
uint64_t reg;
|
||
|
||
data = safe_read_uleb128 (data + 1, end, ®);
|
||
fprintf_filtered (stream, _("a variable in $%s"),
|
||
locexpr_regname (gdbarch, reg));
|
||
}
|
||
else if (data[0] == DW_OP_fbreg)
|
||
{
|
||
const struct block *b;
|
||
struct symbol *framefunc;
|
||
int frame_reg = 0;
|
||
int64_t frame_offset;
|
||
const gdb_byte *base_data, *new_data, *save_data = data;
|
||
size_t base_size;
|
||
int64_t base_offset = 0;
|
||
|
||
new_data = safe_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));
|
||
|
||
func_get_frame_base_dwarf_block (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 = safe_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. */
|
||
return save_data;
|
||
}
|
||
|
||
fprintf_filtered (stream,
|
||
_("a variable at frame base reg $%s offset %s+%s"),
|
||
locexpr_regname (gdbarch, frame_reg),
|
||
plongest (base_offset), plongest (frame_offset));
|
||
}
|
||
else if (data[0] >= DW_OP_breg0 && data[0] <= DW_OP_breg31
|
||
&& piece_end_p (data, end))
|
||
{
|
||
int64_t offset;
|
||
|
||
data = safe_read_sleb128 (data + 1, end, &offset);
|
||
|
||
fprintf_filtered (stream,
|
||
_("a variable at offset %s from base reg $%s"),
|
||
plongest (offset),
|
||
locexpr_regname (gdbarch, data[0] - DW_OP_breg0));
|
||
}
|
||
|
||
/* 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 (objfile));
|
||
|
||
data += 1 + addr_size + 1;
|
||
}
|
||
|
||
/* With -gsplit-dwarf a TLS variable can also look like this:
|
||
DW_AT_location : 3 byte block: fc 4 e0
|
||
(DW_OP_GNU_const_index: 4;
|
||
DW_OP_GNU_push_tls_address) */
|
||
else if (data + 3 <= end
|
||
&& data + 1 + (leb128_size = skip_leb128 (data + 1, end)) < end
|
||
&& data[0] == DW_OP_GNU_const_index
|
||
&& leb128_size > 0
|
||
&& data[1 + leb128_size] == DW_OP_GNU_push_tls_address
|
||
&& piece_end_p (data + 2 + leb128_size, end))
|
||
{
|
||
uint64_t offset;
|
||
|
||
data = safe_read_uleb128 (data + 1, end, &offset);
|
||
offset = dwarf2_read_addr_index (per_cu, offset);
|
||
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 (objfile));
|
||
++data;
|
||
}
|
||
|
||
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.
|
||
If there is an error during reading, e.g. we run off the end
|
||
of the buffer, an error is thrown. */
|
||
|
||
static const gdb_byte *
|
||
disassemble_dwarf_expression (struct ui_file *stream,
|
||
struct gdbarch *arch, unsigned int addr_size,
|
||
int offset_size, const gdb_byte *start,
|
||
const gdb_byte *data, const gdb_byte *end,
|
||
int indent, int all,
|
||
struct dwarf2_per_cu_data *per_cu)
|
||
{
|
||
while (data < end
|
||
&& (all
|
||
|| (data[0] != DW_OP_piece && data[0] != DW_OP_bit_piece)))
|
||
{
|
||
enum dwarf_location_atom op = *data++;
|
||
uint64_t ul;
|
||
int64_t l;
|
||
const char *name;
|
||
|
||
name = get_DW_OP_name (op);
|
||
|
||
if (!name)
|
||
error (_("Unrecognized DWARF opcode 0x%02x at %ld"),
|
||
op, (long) (data - 1 - start));
|
||
fprintf_filtered (stream, " %*ld: %s", indent + 4,
|
||
(long) (data - 1 - 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 = safe_read_uleb128 (data, end, &ul);
|
||
fprintf_filtered (stream, " %s", pulongest (ul));
|
||
break;
|
||
case DW_OP_consts:
|
||
data = safe_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]",
|
||
locexpr_regname (arch, op - DW_OP_reg0));
|
||
break;
|
||
|
||
case DW_OP_regx:
|
||
data = safe_read_uleb128 (data, end, &ul);
|
||
fprintf_filtered (stream, " %s [$%s]", pulongest (ul),
|
||
locexpr_regname (arch, (int) ul));
|
||
break;
|
||
|
||
case DW_OP_implicit_value:
|
||
data = safe_read_uleb128 (data, end, &ul);
|
||
data += ul;
|
||
fprintf_filtered (stream, " %s", pulongest (ul));
|
||
break;
|
||
|
||
case DW_OP_breg0:
|
||
case DW_OP_breg1:
|
||
case DW_OP_breg2:
|
||
case DW_OP_breg3:
|
||
case DW_OP_breg4:
|
||
case DW_OP_breg5:
|
||
case DW_OP_breg6:
|
||
case DW_OP_breg7:
|
||
case DW_OP_breg8:
|
||
case DW_OP_breg9:
|
||
case DW_OP_breg10:
|
||
case DW_OP_breg11:
|
||
case DW_OP_breg12:
|
||
case DW_OP_breg13:
|
||
case DW_OP_breg14:
|
||
case DW_OP_breg15:
|
||
case DW_OP_breg16:
|
||
case DW_OP_breg17:
|
||
case DW_OP_breg18:
|
||
case DW_OP_breg19:
|
||
case DW_OP_breg20:
|
||
case DW_OP_breg21:
|
||
case DW_OP_breg22:
|
||
case DW_OP_breg23:
|
||
case DW_OP_breg24:
|
||
case DW_OP_breg25:
|
||
case DW_OP_breg26:
|
||
case DW_OP_breg27:
|
||
case DW_OP_breg28:
|
||
case DW_OP_breg29:
|
||
case DW_OP_breg30:
|
||
case DW_OP_breg31:
|
||
data = safe_read_sleb128 (data, end, &l);
|
||
fprintf_filtered (stream, " %s [$%s]", plongest (l),
|
||
locexpr_regname (arch, op - DW_OP_breg0));
|
||
break;
|
||
|
||
case DW_OP_bregx:
|
||
data = safe_read_uleb128 (data, end, &ul);
|
||
data = safe_read_sleb128 (data, end, &l);
|
||
fprintf_filtered (stream, " register %s [$%s] offset %s",
|
||
pulongest (ul),
|
||
locexpr_regname (arch, (int) ul),
|
||
plongest (l));
|
||
break;
|
||
|
||
case DW_OP_fbreg:
|
||
data = safe_read_sleb128 (data, end, &l);
|
||
fprintf_filtered (stream, " %s", plongest (l));
|
||
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 = safe_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 = safe_read_uleb128 (data, end, &ul);
|
||
fprintf_filtered (stream, " %s (bytes)", pulongest (ul));
|
||
break;
|
||
|
||
case DW_OP_bit_piece:
|
||
{
|
||
uint64_t offset;
|
||
|
||
data = safe_read_uleb128 (data, end, &ul);
|
||
data = safe_read_uleb128 (data, end, &offset);
|
||
fprintf_filtered (stream, " size %s offset %s (bits)",
|
||
pulongest (ul), pulongest (offset));
|
||
}
|
||
break;
|
||
|
||
case DW_OP_GNU_implicit_pointer:
|
||
{
|
||
ul = extract_unsigned_integer (data, offset_size,
|
||
gdbarch_byte_order (arch));
|
||
data += offset_size;
|
||
|
||
data = safe_read_sleb128 (data, end, &l);
|
||
|
||
fprintf_filtered (stream, " DIE %s offset %s",
|
||
phex_nz (ul, offset_size),
|
||
plongest (l));
|
||
}
|
||
break;
|
||
|
||
case DW_OP_GNU_deref_type:
|
||
{
|
||
int addr_size = *data++;
|
||
cu_offset offset;
|
||
struct type *type;
|
||
|
||
data = safe_read_uleb128 (data, end, &ul);
|
||
offset.cu_off = ul;
|
||
type = dwarf2_get_die_type (offset, per_cu);
|
||
fprintf_filtered (stream, "<");
|
||
type_print (type, "", stream, -1);
|
||
fprintf_filtered (stream, " [0x%s]> %d", phex_nz (offset.cu_off, 0),
|
||
addr_size);
|
||
}
|
||
break;
|
||
|
||
case DW_OP_GNU_const_type:
|
||
{
|
||
cu_offset type_die;
|
||
struct type *type;
|
||
|
||
data = safe_read_uleb128 (data, end, &ul);
|
||
type_die.cu_off = ul;
|
||
type = dwarf2_get_die_type (type_die, per_cu);
|
||
fprintf_filtered (stream, "<");
|
||
type_print (type, "", stream, -1);
|
||
fprintf_filtered (stream, " [0x%s]>", phex_nz (type_die.cu_off, 0));
|
||
}
|
||
break;
|
||
|
||
case DW_OP_GNU_regval_type:
|
||
{
|
||
uint64_t reg;
|
||
cu_offset type_die;
|
||
struct type *type;
|
||
|
||
data = safe_read_uleb128 (data, end, ®);
|
||
data = safe_read_uleb128 (data, end, &ul);
|
||
type_die.cu_off = ul;
|
||
|
||
type = dwarf2_get_die_type (type_die, per_cu);
|
||
fprintf_filtered (stream, "<");
|
||
type_print (type, "", stream, -1);
|
||
fprintf_filtered (stream, " [0x%s]> [$%s]",
|
||
phex_nz (type_die.cu_off, 0),
|
||
locexpr_regname (arch, reg));
|
||
}
|
||
break;
|
||
|
||
case DW_OP_GNU_convert:
|
||
case DW_OP_GNU_reinterpret:
|
||
{
|
||
cu_offset type_die;
|
||
|
||
data = safe_read_uleb128 (data, end, &ul);
|
||
type_die.cu_off = ul;
|
||
|
||
if (type_die.cu_off == 0)
|
||
fprintf_filtered (stream, "<0>");
|
||
else
|
||
{
|
||
struct type *type;
|
||
|
||
type = dwarf2_get_die_type (type_die, per_cu);
|
||
fprintf_filtered (stream, "<");
|
||
type_print (type, "", stream, -1);
|
||
fprintf_filtered (stream, " [0x%s]>", phex_nz (type_die.cu_off, 0));
|
||
}
|
||
}
|
||
break;
|
||
|
||
case DW_OP_GNU_entry_value:
|
||
data = safe_read_uleb128 (data, end, &ul);
|
||
fputc_filtered ('\n', stream);
|
||
disassemble_dwarf_expression (stream, arch, addr_size, offset_size,
|
||
start, data, data + ul, indent + 2,
|
||
all, per_cu);
|
||
data += ul;
|
||
continue;
|
||
|
||
case DW_OP_GNU_parameter_ref:
|
||
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_GNU_addr_index:
|
||
data = safe_read_uleb128 (data, end, &ul);
|
||
ul = dwarf2_read_addr_index (per_cu, ul);
|
||
fprintf_filtered (stream, " 0x%s", phex_nz (ul, addr_size));
|
||
break;
|
||
case DW_OP_GNU_const_index:
|
||
data = safe_read_uleb128 (data, end, &ul);
|
||
ul = dwarf2_read_addr_index (per_cu, ul);
|
||
fprintf_filtered (stream, " %s", pulongest (ul));
|
||
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, size_t size,
|
||
struct objfile *objfile, unsigned int addr_size,
|
||
int offset_size, struct dwarf2_per_cu_data *per_cu)
|
||
{
|
||
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, per_cu,
|
||
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)
|
||
{
|
||
fprintf_filtered (stream, _("a complex DWARF expression:\n"));
|
||
data = disassemble_dwarf_expression (stream,
|
||
get_objfile_arch (objfile),
|
||
addr_size, offset_size, data,
|
||
data, end, 0,
|
||
dwarf2_always_disassemble,
|
||
per_cu);
|
||
}
|
||
|
||
if (data < end)
|
||
{
|
||
int empty = data == here;
|
||
|
||
if (disassemble)
|
||
fprintf_filtered (stream, " ");
|
||
if (data[0] == DW_OP_piece)
|
||
{
|
||
uint64_t bytes;
|
||
|
||
data = safe_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)
|
||
{
|
||
uint64_t bits, offset;
|
||
|
||
data = safe_read_uleb128 (data + 1, end, &bits);
|
||
data = safe_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,
|
||
dlbaton->per_cu);
|
||
}
|
||
|
||
/* 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->size == 0)
|
||
value->optimized_out = 1;
|
||
else
|
||
dwarf2_compile_expr_to_ax (ax, value, gdbarch, addr_size,
|
||
dlbaton->data, dlbaton->data + dlbaton->size,
|
||
dlbaton->per_cu);
|
||
}
|
||
|
||
/* symbol_computed_ops 'generate_c_location' method. */
|
||
|
||
static void
|
||
locexpr_generate_c_location (struct symbol *sym, struct ui_file *stream,
|
||
struct gdbarch *gdbarch,
|
||
unsigned char *registers_used,
|
||
CORE_ADDR pc, const char *result_name)
|
||
{
|
||
struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (sym);
|
||
unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu);
|
||
|
||
if (dlbaton->size == 0)
|
||
error (_("symbol \"%s\" is optimized out"), SYMBOL_NATURAL_NAME (sym));
|
||
|
||
compile_dwarf_expr_to_c (stream, result_name,
|
||
sym, pc, gdbarch, registers_used, addr_size,
|
||
dlbaton->data, dlbaton->data + dlbaton->size,
|
||
dlbaton->per_cu);
|
||
}
|
||
|
||
/* The set of location functions used with the DWARF-2 expression
|
||
evaluator. */
|
||
const struct symbol_computed_ops dwarf2_locexpr_funcs = {
|
||
locexpr_read_variable,
|
||
locexpr_read_variable_at_entry,
|
||
locexpr_read_needs_frame,
|
||
locexpr_describe_location,
|
||
0, /* location_has_loclist */
|
||
locexpr_tracepoint_var_ref,
|
||
locexpr_generate_c_location
|
||
};
|
||
|
||
|
||
/* 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;
|
||
CORE_ADDR pc = frame ? get_frame_address_in_block (frame) : 0;
|
||
|
||
data = dwarf2_find_location_expression (dlbaton, &size, pc);
|
||
val = dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol), frame, data, size,
|
||
dlbaton->per_cu);
|
||
|
||
return val;
|
||
}
|
||
|
||
/* Read variable SYMBOL like loclist_read_variable at (callee) FRAME's function
|
||
entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
|
||
will be thrown.
|
||
|
||
Function always returns non-NULL value, it may be marked optimized out if
|
||
inferior frame information is not available. It throws NO_ENTRY_VALUE_ERROR
|
||
if it cannot resolve the parameter for any reason. */
|
||
|
||
static struct value *
|
||
loclist_read_variable_at_entry (struct symbol *symbol, struct frame_info *frame)
|
||
{
|
||
struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol);
|
||
const gdb_byte *data;
|
||
size_t size;
|
||
CORE_ADDR pc;
|
||
|
||
if (frame == NULL || !get_frame_func_if_available (frame, &pc))
|
||
return allocate_optimized_out_value (SYMBOL_TYPE (symbol));
|
||
|
||
data = dwarf2_find_location_expression (dlbaton, &size, pc);
|
||
if (data == NULL)
|
||
return allocate_optimized_out_value (SYMBOL_TYPE (symbol));
|
||
|
||
return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol), frame, data, size);
|
||
}
|
||
|
||
/* 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);
|
||
const gdb_byte *loc_ptr, *buf_end;
|
||
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);
|
||
/* 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;
|
||
int done = 0;
|
||
|
||
loc_ptr = dlbaton->data;
|
||
buf_end = dlbaton->data + dlbaton->size;
|
||
|
||
fprintf_filtered (stream, _("multi-location:\n"));
|
||
|
||
/* Iterate through locations until we run out. */
|
||
while (!done)
|
||
{
|
||
CORE_ADDR low = 0, high = 0; /* init for gcc -Wall */
|
||
int length;
|
||
enum debug_loc_kind kind;
|
||
const gdb_byte *new_ptr = NULL; /* init for gcc -Wall */
|
||
|
||
if (dlbaton->from_dwo)
|
||
kind = decode_debug_loc_dwo_addresses (dlbaton->per_cu,
|
||
loc_ptr, buf_end, &new_ptr,
|
||
&low, &high, byte_order);
|
||
else
|
||
kind = decode_debug_loc_addresses (loc_ptr, buf_end, &new_ptr,
|
||
&low, &high,
|
||
byte_order, addr_size,
|
||
signed_addr_p);
|
||
loc_ptr = new_ptr;
|
||
switch (kind)
|
||
{
|
||
case DEBUG_LOC_END_OF_LIST:
|
||
done = 1;
|
||
continue;
|
||
case DEBUG_LOC_BASE_ADDRESS:
|
||
base_address = high + base_offset;
|
||
fprintf_filtered (stream, _(" Base address %s"),
|
||
paddress (gdbarch, base_address));
|
||
continue;
|
||
case DEBUG_LOC_START_END:
|
||
case DEBUG_LOC_START_LENGTH:
|
||
break;
|
||
case DEBUG_LOC_BUFFER_OVERFLOW:
|
||
case DEBUG_LOC_INVALID_ENTRY:
|
||
error (_("Corrupted DWARF expression for symbol \"%s\"."),
|
||
SYMBOL_PRINT_NAME (symbol));
|
||
default:
|
||
gdb_assert_not_reached ("bad debug_loc_kind");
|
||
}
|
||
|
||
/* Otherwise, a location expression entry. */
|
||
low += base_address;
|
||
high += base_address;
|
||
|
||
low = gdbarch_adjust_dwarf2_addr (gdbarch, low);
|
||
high = gdbarch_adjust_dwarf2_addr (gdbarch, high);
|
||
|
||
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,
|
||
dlbaton->per_cu);
|
||
|
||
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 = dwarf2_find_location_expression (dlbaton, &size, ax->scope);
|
||
if (size == 0)
|
||
value->optimized_out = 1;
|
||
else
|
||
dwarf2_compile_expr_to_ax (ax, value, gdbarch, addr_size, data, data + size,
|
||
dlbaton->per_cu);
|
||
}
|
||
|
||
/* symbol_computed_ops 'generate_c_location' method. */
|
||
|
||
static void
|
||
loclist_generate_c_location (struct symbol *sym, struct ui_file *stream,
|
||
struct gdbarch *gdbarch,
|
||
unsigned char *registers_used,
|
||
CORE_ADDR pc, const char *result_name)
|
||
{
|
||
struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (sym);
|
||
unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu);
|
||
const gdb_byte *data;
|
||
size_t size;
|
||
|
||
data = dwarf2_find_location_expression (dlbaton, &size, pc);
|
||
if (size == 0)
|
||
error (_("symbol \"%s\" is optimized out"), SYMBOL_NATURAL_NAME (sym));
|
||
|
||
compile_dwarf_expr_to_c (stream, result_name,
|
||
sym, pc, gdbarch, registers_used, 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_variable_at_entry,
|
||
loclist_read_needs_frame,
|
||
loclist_describe_location,
|
||
1, /* location_has_loclist */
|
||
loclist_tracepoint_var_ref,
|
||
loclist_generate_c_location
|
||
};
|
||
|
||
/* Provide a prototype to silence -Wmissing-prototypes. */
|
||
extern initialize_file_ftype _initialize_dwarf2loc;
|
||
|
||
void
|
||
_initialize_dwarf2loc (void)
|
||
{
|
||
add_setshow_zuinteger_cmd ("entry-values", class_maintenance,
|
||
&entry_values_debug,
|
||
_("Set entry values and tail call frames "
|
||
"debugging."),
|
||
_("Show entry values and tail call frames "
|
||
"debugging."),
|
||
_("When non-zero, the process of determining "
|
||
"parameter values from function entry point "
|
||
"and tail call frames will be printed."),
|
||
NULL,
|
||
show_entry_values_debug,
|
||
&setdebuglist, &showdebuglist);
|
||
}
|