1918 lines
47 KiB
C
1918 lines
47 KiB
C
/* Stack unwinding code based on dwarf2 frame info for GDB, the GNU debugger.
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Copyright 2001, 2002 Free Software Foundation, Inc.
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Contributed by Jiri Smid, SuSE Labs.
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Based on code written by Daniel Berlin (dan@dberlin.org).
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 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, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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#include "defs.h"
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#include "gdbcore.h"
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#include "symtab.h"
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#include "symfile.h"
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#include "objfiles.h"
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#include "target.h"
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#include "elf/dwarf2.h"
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#include "inferior.h"
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#include "regcache.h"
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#include "dwarf2cfi.h"
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#include "gdb_assert.h"
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/* Common Information Entry - holds information that is shared among many
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Frame Descriptors. */
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struct cie_unit
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{
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/* Offset of this unit in .debug_frame or .eh_frame. */
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ULONGEST offset;
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/* A null-terminated string that identifies the augmentation to this CIE or
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to the FDEs that use it. */
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char *augmentation;
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/* A constant that is factored out of all advance location instructions. */
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unsigned int code_align;
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/* A constant that is factored out of all offset instructions. */
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int data_align;
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/* A constant that indicates which regiter represents the return address
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of a function. */
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unsigned char ra;
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/* Indicates how addresses are encoded. */
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unsigned char addr_encoding;
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/* Pointer and length of the cie program. */
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char *data;
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unsigned int data_length;
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struct objfile *objfile;
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/* Next in chain. */
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struct cie_unit *next;
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};
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/* Frame Description Entry. */
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struct fde_unit
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{
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/* Address of the first location associated with this entry. */
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CORE_ADDR initial_location;
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/* Length of program section described by this entry. */
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CORE_ADDR address_range;
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/* Pointer to asociated CIE. */
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struct cie_unit *cie_ptr;
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/* Pointer and length of the cie program. */
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char *data;
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unsigned int data_length;
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};
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struct fde_array
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{
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struct fde_unit **array;
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int elems;
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int array_size;
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};
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struct frame_state_reg
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{
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union
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{
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unsigned int reg;
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long offset;
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unsigned char *exp;
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}
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loc;
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enum
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{
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REG_UNSAVED,
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REG_SAVED_OFFSET,
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REG_SAVED_REG,
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REG_SAVED_EXP,
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}
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how;
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};
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struct frame_state
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{
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/* Each register save state can be described in terms of a CFA slot,
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another register, or a location expression. */
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struct frame_state_regs
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{
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struct frame_state_reg *reg;
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/* Used to implement DW_CFA_remember_state. */
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struct frame_state_regs *prev;
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}
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regs;
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/* The CFA can be described in terms of a reg+offset or a
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location expression. */
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long cfa_offset;
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int cfa_reg;
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unsigned char *cfa_exp;
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enum
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{
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CFA_UNSET,
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CFA_REG_OFFSET,
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CFA_EXP,
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}
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cfa_how;
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/* The PC described by the current frame state. */
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CORE_ADDR pc;
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/* The information we care about from the CIE/FDE. */
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int data_align;
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unsigned int code_align;
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unsigned char retaddr_column;
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unsigned char addr_encoding;
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struct objfile *objfile;
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};
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enum ptr_encoding
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{
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PE_absptr = DW_EH_PE_absptr,
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PE_pcrel = DW_EH_PE_pcrel,
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PE_textrel = DW_EH_PE_textrel,
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PE_datarel = DW_EH_PE_datarel,
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PE_funcrel = DW_EH_PE_funcrel
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};
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#define UNWIND_CONTEXT(fi) ((struct context *) (deprecated_get_frame_context (fi)))
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static struct cie_unit *cie_chunks;
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static struct fde_array fde_chunks;
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/* Obstack for allocating temporary storage used during unwind operations. */
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static struct obstack unwind_tmp_obstack;
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extern file_ptr dwarf_frame_offset;
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extern unsigned int dwarf_frame_size;
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extern file_ptr dwarf_eh_frame_offset;
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extern unsigned int dwarf_eh_frame_size;
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extern char *dwarf2_read_section (struct objfile *objfile, file_ptr offset,
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unsigned int size);
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static struct fde_unit *fde_unit_alloc (void);
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static struct cie_unit *cie_unit_alloc (void);
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static void fde_chunks_need_space ();
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static void unwind_tmp_obstack_init ();
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static void unwind_tmp_obstack_free ();
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static unsigned int read_1u (bfd *abfd, char **p);
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static int read_1s (bfd *abfd, char **p);
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static unsigned int read_2u (bfd *abfd, char **p);
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static int read_2s (bfd *abfd, char **p);
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static unsigned int read_4u (bfd *abfd, char **p);
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static int read_4s (bfd *abfd, char **p);
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static ULONGEST read_8u (bfd *abfd, char **p);
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static LONGEST read_8s (bfd *abfd, char **p);
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static ULONGEST read_uleb128 (bfd *abfd, char **p);
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static LONGEST read_sleb128 (bfd *abfd, char **p);
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static CORE_ADDR read_pointer (bfd *abfd, char **p);
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static CORE_ADDR read_encoded_pointer (bfd *abfd, char **p,
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unsigned char encoding);
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static enum ptr_encoding pointer_encoding (unsigned char encoding);
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static LONGEST read_initial_length (bfd *abfd, char *buf, int *bytes_read);
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static ULONGEST read_length (bfd *abfd, char *buf, int *bytes_read,
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int dwarf64);
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static int is_cie (ULONGEST cie_id, int dwarf64);
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static int compare_fde_unit (const void *a, const void *b);
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void dwarf2_build_frame_info (struct objfile *objfile);
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static void execute_cfa_program (struct objfile *objfile, char *insn_ptr,
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char *insn_end, struct context *context,
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struct frame_state *fs);
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static struct fde_unit *get_fde_for_addr (CORE_ADDR pc);
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static void frame_state_for (struct context *context, struct frame_state *fs);
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static void get_reg (char *reg, struct context *context, int regnum);
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static CORE_ADDR execute_stack_op (struct objfile *objfile,
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char *op_ptr, char *op_end,
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struct context *context,
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CORE_ADDR initial);
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static void update_context (struct context *context, struct frame_state *fs,
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int chain);
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/* Memory allocation functions. */
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static struct fde_unit *
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fde_unit_alloc (void)
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{
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struct fde_unit *fde;
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fde = (struct fde_unit *) xmalloc (sizeof (struct fde_unit));
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memset (fde, 0, sizeof (struct fde_unit));
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return fde;
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}
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static struct cie_unit *
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cie_unit_alloc (void)
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{
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struct cie_unit *cie;
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cie = (struct cie_unit *) xmalloc (sizeof (struct cie_unit));
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memset (cie, 0, sizeof (struct cie_unit));
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return cie;
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}
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static void
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fde_chunks_need_space (void)
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{
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if (fde_chunks.elems < fde_chunks.array_size)
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return;
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fde_chunks.array_size =
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fde_chunks.array_size ? 2 * fde_chunks.array_size : 1024;
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fde_chunks.array =
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xrealloc (fde_chunks.array,
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sizeof (struct fde_unit) * fde_chunks.array_size);
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}
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/* Alocate a new `struct context' on temporary obstack. */
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struct context *
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context_alloc (void)
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{
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struct context *context;
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int regs_size = sizeof (struct context_reg) * NUM_REGS;
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context = (struct context *) obstack_alloc (&unwind_tmp_obstack,
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sizeof (struct context));
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memset (context, 0, sizeof (struct context));
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context->reg = (struct context_reg *) obstack_alloc (&unwind_tmp_obstack,
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regs_size);
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memset (context->reg, 0, regs_size);
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return context;
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}
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/* Alocate a new `struct frame_state' on temporary obstack. */
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struct frame_state *
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frame_state_alloc (void)
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{
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struct frame_state *fs;
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int regs_size = sizeof (struct frame_state_reg) * NUM_REGS;
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fs = (struct frame_state *) obstack_alloc (&unwind_tmp_obstack,
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sizeof (struct frame_state));
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memset (fs, 0, sizeof (struct frame_state));
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fs->regs.reg =
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(struct frame_state_reg *) obstack_alloc (&unwind_tmp_obstack, regs_size);
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memset (fs->regs.reg, 0, regs_size);
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return fs;
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}
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static void
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unwind_tmp_obstack_init (void)
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{
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obstack_init (&unwind_tmp_obstack);
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}
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static void
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unwind_tmp_obstack_free (void)
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{
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obstack_free (&unwind_tmp_obstack, NULL);
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unwind_tmp_obstack_init ();
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}
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void
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context_cpy (struct context *dst, struct context *src)
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{
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int regs_size = sizeof (struct context_reg) * NUM_REGS;
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struct context_reg *dreg;
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/* Since `struct context' contains a pointer to an array with
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register values, make sure we end up with a copy of that array,
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and not with a copy of the pointer to that array. */
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dreg = dst->reg;
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*dst = *src;
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dst->reg = dreg;
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memcpy (dst->reg, src->reg, regs_size);
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}
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static unsigned int
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read_1u (bfd *abfd, char **p)
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{
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unsigned ret;
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ret = bfd_get_8 (abfd, (bfd_byte *) * p);
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(*p)++;
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return ret;
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}
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static int
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read_1s (bfd *abfd, char **p)
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{
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int ret;
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ret = bfd_get_signed_8 (abfd, (bfd_byte *) * p);
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(*p)++;
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return ret;
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}
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static unsigned int
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read_2u (bfd *abfd, char **p)
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{
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unsigned ret;
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ret = bfd_get_16 (abfd, (bfd_byte *) * p);
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(*p)++;
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return ret;
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}
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static int
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read_2s (bfd *abfd, char **p)
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{
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int ret;
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ret = bfd_get_signed_16 (abfd, (bfd_byte *) * p);
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(*p) += 2;
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return ret;
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}
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static unsigned int
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read_4u (bfd *abfd, char **p)
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{
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unsigned int ret;
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ret = bfd_get_32 (abfd, (bfd_byte *) * p);
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(*p) += 4;
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return ret;
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}
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static int
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read_4s (bfd *abfd, char **p)
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{
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int ret;
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ret = bfd_get_signed_32 (abfd, (bfd_byte *) * p);
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(*p) += 4;
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return ret;
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}
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static ULONGEST
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read_8u (bfd *abfd, char **p)
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{
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ULONGEST ret;
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ret = bfd_get_64 (abfd, (bfd_byte *) * p);
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(*p) += 8;
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return ret;
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}
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static LONGEST
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read_8s (bfd *abfd, char **p)
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{
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LONGEST ret;
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ret = bfd_get_signed_64 (abfd, (bfd_byte *) * p);
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(*p) += 8;
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return ret;
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}
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static ULONGEST
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read_uleb128 (bfd *abfd, char **p)
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{
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ULONGEST ret;
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int i, shift;
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unsigned char byte;
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ret = 0;
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shift = 0;
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i = 0;
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while (1)
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{
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byte = bfd_get_8 (abfd, (bfd_byte *) * p);
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(*p)++;
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ret |= ((unsigned long) (byte & 127) << shift);
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if ((byte & 128) == 0)
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{
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break;
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}
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shift += 7;
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}
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return ret;
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}
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static LONGEST
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read_sleb128 (bfd *abfd, char **p)
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{
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LONGEST ret;
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int i, shift, size, num_read;
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unsigned char byte;
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ret = 0;
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shift = 0;
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size = 32;
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num_read = 0;
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i = 0;
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while (1)
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{
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byte = bfd_get_8 (abfd, (bfd_byte *) * p);
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(*p)++;
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ret |= ((long) (byte & 127) << shift);
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shift += 7;
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if ((byte & 128) == 0)
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{
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break;
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}
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}
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if ((shift < size) && (byte & 0x40))
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{
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ret |= -(1 << shift);
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}
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return ret;
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}
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static CORE_ADDR
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read_pointer (bfd *abfd, char **p)
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{
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switch (TARGET_ADDR_BIT / TARGET_CHAR_BIT)
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{
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case 4:
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return read_4u (abfd, p);
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case 8:
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return read_8u (abfd, p);
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default:
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error ("dwarf cfi error: unsupported target address length.");
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}
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}
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/* Read the appropriate amount of data from *P and return the
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resulting value based on ENCODING, which the calling function must
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provide. */
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static CORE_ADDR
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read_encoded_pointer (bfd *abfd, char **p, unsigned char encoding)
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{
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CORE_ADDR ret;
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switch (encoding & 0x0f)
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{
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case DW_EH_PE_absptr:
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ret = read_pointer (abfd, p);
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break;
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case DW_EH_PE_uleb128:
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ret = read_uleb128 (abfd, p);
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break;
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case DW_EH_PE_sleb128:
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ret = read_sleb128 (abfd, p);
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break;
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case DW_EH_PE_udata2:
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ret = read_2u (abfd, p);
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break;
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case DW_EH_PE_udata4:
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ret = read_4u (abfd, p);
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break;
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case DW_EH_PE_udata8:
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ret = read_8u (abfd, p);
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break;
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case DW_EH_PE_sdata2:
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ret = read_2s (abfd, p);
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break;
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case DW_EH_PE_sdata4:
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ret = read_4s (abfd, p);
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break;
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case DW_EH_PE_sdata8:
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ret = read_8s (abfd, p);
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break;
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default:
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internal_error (__FILE__, __LINE__,
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"read_encoded_pointer: unknown pointer encoding");
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}
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return ret;
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}
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/* The variable 'encoding' carries three different flags:
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- encoding & 0x0f : size of the address (handled in read_encoded_pointer())
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- encoding & 0x70 : type (absolute, relative, ...)
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- encoding & 0x80 : indirect flag (DW_EH_PE_indirect == 0x80). */
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enum ptr_encoding
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pointer_encoding (unsigned char encoding)
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{
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int ret;
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if (encoding & DW_EH_PE_indirect)
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warning ("CFI: Unsupported pointer encoding: DW_EH_PE_indirect");
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switch (encoding & 0x70)
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{
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case DW_EH_PE_absptr:
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case DW_EH_PE_pcrel:
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case DW_EH_PE_textrel:
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case DW_EH_PE_datarel:
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case DW_EH_PE_funcrel:
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ret = encoding & 0x70;
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break;
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default:
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internal_error (__FILE__, __LINE__, "CFI: unknown pointer encoding");
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}
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return ret;
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}
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static LONGEST
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read_initial_length (bfd *abfd, char *buf, int *bytes_read)
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{
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LONGEST ret = 0;
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ret = bfd_get_32 (abfd, (bfd_byte *) buf);
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if (ret == 0xffffffff)
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{
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ret = bfd_get_64 (abfd, (bfd_byte *) buf + 4);
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*bytes_read = 12;
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}
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else
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{
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*bytes_read = 4;
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}
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return ret;
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}
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static ULONGEST
|
||
read_length (bfd *abfd, char *buf, int *bytes_read, int dwarf64)
|
||
{
|
||
if (dwarf64)
|
||
{
|
||
*bytes_read = 8;
|
||
return read_8u (abfd, &buf);
|
||
}
|
||
else
|
||
{
|
||
*bytes_read = 4;
|
||
return read_4u (abfd, &buf);
|
||
}
|
||
}
|
||
|
||
static void
|
||
execute_cfa_program (struct objfile *objfile, char *insn_ptr, char *insn_end,
|
||
struct context *context, struct frame_state *fs)
|
||
{
|
||
struct frame_state_regs *unused_rs = NULL;
|
||
|
||
/* Don't allow remember/restore between CIE and FDE programs. */
|
||
fs->regs.prev = NULL;
|
||
|
||
while (insn_ptr < insn_end && fs->pc < context->ra)
|
||
{
|
||
unsigned char insn = *insn_ptr++;
|
||
ULONGEST reg, uoffset;
|
||
LONGEST offset;
|
||
|
||
if (insn & DW_CFA_advance_loc)
|
||
fs->pc += (insn & 0x3f) * fs->code_align;
|
||
else if (insn & DW_CFA_offset)
|
||
{
|
||
reg = insn & 0x3f;
|
||
uoffset = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
offset = (long) uoffset *fs->data_align;
|
||
fs->regs.reg[reg].how = REG_SAVED_OFFSET;
|
||
fs->regs.reg[reg].loc.offset = offset;
|
||
}
|
||
else if (insn & DW_CFA_restore)
|
||
{
|
||
reg = insn & 0x3f;
|
||
fs->regs.reg[reg].how = REG_UNSAVED;
|
||
}
|
||
else
|
||
switch (insn)
|
||
{
|
||
case DW_CFA_set_loc:
|
||
fs->pc = read_encoded_pointer (objfile->obfd, &insn_ptr,
|
||
fs->addr_encoding);
|
||
|
||
if (pointer_encoding (fs->addr_encoding) != PE_absptr)
|
||
warning ("CFI: DW_CFA_set_loc uses relative addressing");
|
||
|
||
break;
|
||
|
||
case DW_CFA_advance_loc1:
|
||
fs->pc += read_1u (objfile->obfd, &insn_ptr);
|
||
break;
|
||
case DW_CFA_advance_loc2:
|
||
fs->pc += read_2u (objfile->obfd, &insn_ptr);
|
||
break;
|
||
case DW_CFA_advance_loc4:
|
||
fs->pc += read_4u (objfile->obfd, &insn_ptr);
|
||
break;
|
||
|
||
case DW_CFA_offset_extended:
|
||
reg = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
uoffset = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
offset = (long) uoffset *fs->data_align;
|
||
fs->regs.reg[reg].how = REG_SAVED_OFFSET;
|
||
fs->regs.reg[reg].loc.offset = offset;
|
||
break;
|
||
|
||
case DW_CFA_restore_extended:
|
||
reg = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
fs->regs.reg[reg].how = REG_UNSAVED;
|
||
break;
|
||
|
||
case DW_CFA_undefined:
|
||
case DW_CFA_same_value:
|
||
case DW_CFA_nop:
|
||
break;
|
||
|
||
case DW_CFA_register:
|
||
{
|
||
ULONGEST reg2;
|
||
reg = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
reg2 = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
fs->regs.reg[reg].how = REG_SAVED_REG;
|
||
fs->regs.reg[reg].loc.reg = reg2;
|
||
}
|
||
break;
|
||
|
||
case DW_CFA_remember_state:
|
||
{
|
||
struct frame_state_regs *new_rs;
|
||
if (unused_rs)
|
||
{
|
||
new_rs = unused_rs;
|
||
unused_rs = unused_rs->prev;
|
||
}
|
||
else
|
||
new_rs = xmalloc (sizeof (struct frame_state_regs));
|
||
|
||
*new_rs = fs->regs;
|
||
fs->regs.prev = new_rs;
|
||
}
|
||
break;
|
||
|
||
case DW_CFA_restore_state:
|
||
{
|
||
struct frame_state_regs *old_rs = fs->regs.prev;
|
||
fs->regs = *old_rs;
|
||
old_rs->prev = unused_rs;
|
||
unused_rs = old_rs;
|
||
}
|
||
break;
|
||
|
||
case DW_CFA_def_cfa:
|
||
reg = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
uoffset = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
fs->cfa_reg = reg;
|
||
fs->cfa_offset = uoffset;
|
||
fs->cfa_how = CFA_REG_OFFSET;
|
||
break;
|
||
|
||
case DW_CFA_def_cfa_register:
|
||
reg = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
fs->cfa_reg = reg;
|
||
fs->cfa_how = CFA_REG_OFFSET;
|
||
break;
|
||
|
||
case DW_CFA_def_cfa_offset:
|
||
uoffset = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
fs->cfa_offset = uoffset;
|
||
break;
|
||
|
||
case DW_CFA_def_cfa_expression:
|
||
uoffset = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
fs->cfa_exp = insn_ptr;
|
||
fs->cfa_how = CFA_EXP;
|
||
insn_ptr += uoffset;
|
||
break;
|
||
|
||
case DW_CFA_expression:
|
||
reg = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
uoffset = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
fs->regs.reg[reg].how = REG_SAVED_EXP;
|
||
fs->regs.reg[reg].loc.exp = insn_ptr;
|
||
insn_ptr += uoffset;
|
||
break;
|
||
|
||
/* From the 2.1 draft. */
|
||
case DW_CFA_offset_extended_sf:
|
||
reg = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
offset = read_sleb128 (objfile->obfd, &insn_ptr);
|
||
offset *= fs->data_align;
|
||
fs->regs.reg[reg].how = REG_SAVED_OFFSET;
|
||
fs->regs.reg[reg].loc.offset = offset;
|
||
break;
|
||
|
||
case DW_CFA_def_cfa_sf:
|
||
reg = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
offset = read_sleb128 (objfile->obfd, &insn_ptr);
|
||
fs->cfa_offset = offset;
|
||
fs->cfa_reg = reg;
|
||
fs->cfa_how = CFA_REG_OFFSET;
|
||
break;
|
||
|
||
case DW_CFA_def_cfa_offset_sf:
|
||
uoffset = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
fs->cfa_offset = uoffset;
|
||
/* cfa_how deliberately not set. */
|
||
break;
|
||
|
||
case DW_CFA_GNU_window_save:
|
||
/* ??? Hardcoded for SPARC register window configuration. */
|
||
for (reg = 16; reg < 32; ++reg)
|
||
{
|
||
fs->regs.reg[reg].how = REG_SAVED_OFFSET;
|
||
fs->regs.reg[reg].loc.offset = (reg - 16) * sizeof (void *);
|
||
}
|
||
break;
|
||
|
||
case DW_CFA_GNU_args_size:
|
||
uoffset = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
context->args_size = uoffset;
|
||
break;
|
||
|
||
case DW_CFA_GNU_negative_offset_extended:
|
||
/* Obsoleted by DW_CFA_offset_extended_sf, but used by
|
||
older PowerPC code. */
|
||
reg = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
uoffset = read_uleb128 (objfile->obfd, &insn_ptr);
|
||
offset = (long) uoffset *fs->data_align;
|
||
fs->regs.reg[reg].how = REG_SAVED_OFFSET;
|
||
fs->regs.reg[reg].loc.offset = -offset;
|
||
break;
|
||
|
||
default:
|
||
error ("dwarf cfi error: unknown cfa instruction %d.", insn);
|
||
}
|
||
}
|
||
}
|
||
|
||
static struct fde_unit *
|
||
get_fde_for_addr (CORE_ADDR pc)
|
||
{
|
||
size_t lo, hi;
|
||
struct fde_unit *fde = NULL;
|
||
lo = 0;
|
||
hi = fde_chunks.elems;
|
||
|
||
while (lo < hi)
|
||
{
|
||
size_t i = (lo + hi) / 2;
|
||
fde = fde_chunks.array[i];
|
||
if (pc < fde->initial_location)
|
||
hi = i;
|
||
else if (pc >= fde->initial_location + fde->address_range)
|
||
lo = i + 1;
|
||
else
|
||
return fde;
|
||
}
|
||
return 0;
|
||
}
|
||
|
||
static void
|
||
frame_state_for (struct context *context, struct frame_state *fs)
|
||
{
|
||
struct fde_unit *fde;
|
||
struct cie_unit *cie;
|
||
|
||
context->args_size = 0;
|
||
context->lsda = 0;
|
||
|
||
fde = get_fde_for_addr (context->ra - 1);
|
||
|
||
if (fde == NULL)
|
||
return;
|
||
|
||
fs->pc = fde->initial_location;
|
||
|
||
gdb_assert (fde->cie_ptr != NULL);
|
||
|
||
cie = fde->cie_ptr;
|
||
|
||
fs->code_align = cie->code_align;
|
||
fs->data_align = cie->data_align;
|
||
fs->retaddr_column = cie->ra;
|
||
fs->addr_encoding = cie->addr_encoding;
|
||
fs->objfile = cie->objfile;
|
||
|
||
execute_cfa_program (cie->objfile, cie->data,
|
||
cie->data + cie->data_length, context, fs);
|
||
execute_cfa_program (cie->objfile, fde->data,
|
||
fde->data + fde->data_length, context, fs);
|
||
}
|
||
|
||
static void
|
||
get_reg (char *reg, struct context *context, int regnum)
|
||
{
|
||
switch (context->reg[regnum].how)
|
||
{
|
||
case REG_CTX_UNSAVED:
|
||
deprecated_read_register_gen (regnum, reg);
|
||
break;
|
||
case REG_CTX_SAVED_OFFSET:
|
||
target_read_memory (context->cfa + context->reg[regnum].loc.offset,
|
||
reg, REGISTER_RAW_SIZE (regnum));
|
||
break;
|
||
case REG_CTX_SAVED_REG:
|
||
deprecated_read_register_gen (context->reg[regnum].loc.reg, reg);
|
||
break;
|
||
case REG_CTX_SAVED_ADDR:
|
||
target_read_memory (context->reg[regnum].loc.addr,
|
||
reg, REGISTER_RAW_SIZE (regnum));
|
||
break;
|
||
case REG_CTX_VALUE:
|
||
memcpy (reg, &context->reg[regnum].loc.addr,
|
||
REGISTER_RAW_SIZE (regnum));
|
||
break;
|
||
default:
|
||
internal_error (__FILE__, __LINE__, "get_reg: unknown register rule");
|
||
}
|
||
}
|
||
|
||
/* Decode a DW_OP stack program. Return the top of stack. Push INITIAL
|
||
onto the stack to start. */
|
||
static CORE_ADDR
|
||
execute_stack_op (struct objfile *objfile,
|
||
char *op_ptr, char *op_end, struct context *context,
|
||
CORE_ADDR initial)
|
||
{
|
||
CORE_ADDR stack[64]; /* ??? Assume this is enough. */
|
||
int stack_elt;
|
||
|
||
stack[0] = initial;
|
||
stack_elt = 1;
|
||
|
||
while (op_ptr < op_end)
|
||
{
|
||
enum dwarf_location_atom op = *op_ptr++;
|
||
CORE_ADDR result;
|
||
ULONGEST reg;
|
||
LONGEST offset;
|
||
|
||
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:
|
||
result = op - DW_OP_lit0;
|
||
break;
|
||
|
||
case DW_OP_addr:
|
||
result = read_pointer (objfile->obfd, &op_ptr);
|
||
break;
|
||
|
||
case DW_OP_const1u:
|
||
result = read_1u (objfile->obfd, &op_ptr);
|
||
break;
|
||
case DW_OP_const1s:
|
||
result = read_1s (objfile->obfd, &op_ptr);
|
||
break;
|
||
case DW_OP_const2u:
|
||
result = read_2u (objfile->obfd, &op_ptr);
|
||
break;
|
||
case DW_OP_const2s:
|
||
result = read_2s (objfile->obfd, &op_ptr);
|
||
break;
|
||
case DW_OP_const4u:
|
||
result = read_4u (objfile->obfd, &op_ptr);
|
||
break;
|
||
case DW_OP_const4s:
|
||
result = read_4s (objfile->obfd, &op_ptr);
|
||
break;
|
||
case DW_OP_const8u:
|
||
result = read_8u (objfile->obfd, &op_ptr);
|
||
break;
|
||
case DW_OP_const8s:
|
||
result = read_8s (objfile->obfd, &op_ptr);
|
||
break;
|
||
case DW_OP_constu:
|
||
result = read_uleb128 (objfile->obfd, &op_ptr);
|
||
break;
|
||
case DW_OP_consts:
|
||
result = read_sleb128 (objfile->obfd, &op_ptr);
|
||
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:
|
||
get_reg ((char *) &result, context, op - DW_OP_reg0);
|
||
break;
|
||
case DW_OP_regx:
|
||
reg = read_uleb128 (objfile->obfd, &op_ptr);
|
||
get_reg ((char *) &result, context, reg);
|
||
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:
|
||
offset = read_sleb128 (objfile->obfd, &op_ptr);
|
||
get_reg ((char *) &result, context, op - DW_OP_breg0);
|
||
result += offset;
|
||
break;
|
||
case DW_OP_bregx:
|
||
reg = read_uleb128 (objfile->obfd, &op_ptr);
|
||
offset = read_sleb128 (objfile->obfd, &op_ptr);
|
||
get_reg ((char *) &result, context, reg);
|
||
result += offset;
|
||
break;
|
||
|
||
case DW_OP_dup:
|
||
if (stack_elt < 1)
|
||
internal_error (__FILE__, __LINE__, "execute_stack_op error");
|
||
result = stack[stack_elt - 1];
|
||
break;
|
||
|
||
case DW_OP_drop:
|
||
if (--stack_elt < 0)
|
||
internal_error (__FILE__, __LINE__, "execute_stack_op error");
|
||
goto no_push;
|
||
|
||
case DW_OP_pick:
|
||
offset = *op_ptr++;
|
||
if (offset >= stack_elt - 1)
|
||
internal_error (__FILE__, __LINE__, "execute_stack_op error");
|
||
result = stack[stack_elt - 1 - offset];
|
||
break;
|
||
|
||
case DW_OP_over:
|
||
if (stack_elt < 2)
|
||
internal_error (__FILE__, __LINE__, "execute_stack_op error");
|
||
result = stack[stack_elt - 2];
|
||
break;
|
||
|
||
case DW_OP_rot:
|
||
{
|
||
CORE_ADDR t1, t2, t3;
|
||
|
||
if (stack_elt < 3)
|
||
internal_error (__FILE__, __LINE__, "execute_stack_op error");
|
||
t1 = stack[stack_elt - 1];
|
||
t2 = stack[stack_elt - 2];
|
||
t3 = stack[stack_elt - 3];
|
||
stack[stack_elt - 1] = t2;
|
||
stack[stack_elt - 2] = t3;
|
||
stack[stack_elt - 3] = t1;
|
||
goto no_push;
|
||
}
|
||
|
||
case DW_OP_deref:
|
||
case DW_OP_deref_size:
|
||
case DW_OP_abs:
|
||
case DW_OP_neg:
|
||
case DW_OP_not:
|
||
case DW_OP_plus_uconst:
|
||
/* Unary operations. */
|
||
if (--stack_elt < 0)
|
||
internal_error (__FILE__, __LINE__, "execute_stack_op error");
|
||
result = stack[stack_elt];
|
||
|
||
switch (op)
|
||
{
|
||
case DW_OP_deref:
|
||
{
|
||
int len = TARGET_ADDR_BIT / TARGET_CHAR_BIT;
|
||
if (len != 4 && len != 8)
|
||
internal_error (__FILE__, __LINE__,
|
||
"execute_stack_op error");
|
||
result = read_memory_unsigned_integer (result, len);
|
||
}
|
||
break;
|
||
|
||
case DW_OP_deref_size:
|
||
{
|
||
int len = *op_ptr++;
|
||
if (len != 1 && len != 2 && len != 4 && len != 8)
|
||
internal_error (__FILE__, __LINE__,
|
||
"execute_stack_op error");
|
||
result = read_memory_unsigned_integer (result, len);
|
||
}
|
||
break;
|
||
|
||
case DW_OP_abs:
|
||
if (result < 0)
|
||
result = -result;
|
||
break;
|
||
case DW_OP_neg:
|
||
result = -result;
|
||
break;
|
||
case DW_OP_not:
|
||
result = ~result;
|
||
break;
|
||
case DW_OP_plus_uconst:
|
||
result += read_uleb128 (objfile->obfd, &op_ptr);
|
||
break;
|
||
default:
|
||
break;
|
||
}
|
||
break;
|
||
|
||
case DW_OP_and:
|
||
case DW_OP_div:
|
||
case DW_OP_minus:
|
||
case DW_OP_mod:
|
||
case DW_OP_mul:
|
||
case DW_OP_or:
|
||
case DW_OP_plus:
|
||
case DW_OP_le:
|
||
case DW_OP_ge:
|
||
case DW_OP_eq:
|
||
case DW_OP_lt:
|
||
case DW_OP_gt:
|
||
case DW_OP_ne:
|
||
{
|
||
/* Binary operations. */
|
||
CORE_ADDR first, second;
|
||
if ((stack_elt -= 2) < 0)
|
||
internal_error (__FILE__, __LINE__, "execute_stack_op error");
|
||
second = stack[stack_elt];
|
||
first = stack[stack_elt + 1];
|
||
|
||
switch (op)
|
||
{
|
||
case DW_OP_and:
|
||
result = second & first;
|
||
break;
|
||
case DW_OP_div:
|
||
result = (LONGEST) second / (LONGEST) first;
|
||
break;
|
||
case DW_OP_minus:
|
||
result = second - first;
|
||
break;
|
||
case DW_OP_mod:
|
||
result = (LONGEST) second % (LONGEST) first;
|
||
break;
|
||
case DW_OP_mul:
|
||
result = second * first;
|
||
break;
|
||
case DW_OP_or:
|
||
result = second | first;
|
||
break;
|
||
case DW_OP_plus:
|
||
result = second + first;
|
||
break;
|
||
case DW_OP_shl:
|
||
result = second << first;
|
||
break;
|
||
case DW_OP_shr:
|
||
result = second >> first;
|
||
break;
|
||
case DW_OP_shra:
|
||
result = (LONGEST) second >> first;
|
||
break;
|
||
case DW_OP_xor:
|
||
result = second ^ first;
|
||
break;
|
||
case DW_OP_le:
|
||
result = (LONGEST) first <= (LONGEST) second;
|
||
break;
|
||
case DW_OP_ge:
|
||
result = (LONGEST) first >= (LONGEST) second;
|
||
break;
|
||
case DW_OP_eq:
|
||
result = (LONGEST) first == (LONGEST) second;
|
||
break;
|
||
case DW_OP_lt:
|
||
result = (LONGEST) first < (LONGEST) second;
|
||
break;
|
||
case DW_OP_gt:
|
||
result = (LONGEST) first > (LONGEST) second;
|
||
break;
|
||
case DW_OP_ne:
|
||
result = (LONGEST) first != (LONGEST) second;
|
||
break;
|
||
default:
|
||
error ("execute_stack_op: Unknown DW_OP_ value");
|
||
break;
|
||
}
|
||
}
|
||
break;
|
||
|
||
case DW_OP_skip:
|
||
offset = read_2s (objfile->obfd, &op_ptr);
|
||
op_ptr += offset;
|
||
goto no_push;
|
||
|
||
case DW_OP_bra:
|
||
if (--stack_elt < 0)
|
||
internal_error (__FILE__, __LINE__, "execute_stack_op error");
|
||
offset = read_2s (objfile->obfd, &op_ptr);
|
||
if (stack[stack_elt] != 0)
|
||
op_ptr += offset;
|
||
goto no_push;
|
||
|
||
case DW_OP_nop:
|
||
goto no_push;
|
||
|
||
default:
|
||
internal_error (__FILE__, __LINE__, "execute_stack_op error");
|
||
}
|
||
|
||
/* Most things push a result value. */
|
||
if ((size_t) stack_elt >= sizeof (stack) / sizeof (*stack))
|
||
internal_error (__FILE__, __LINE__, "execute_stack_op error");
|
||
stack[++stack_elt] = result;
|
||
no_push:;
|
||
}
|
||
|
||
/* We were executing this program to get a value. It should be
|
||
at top of stack. */
|
||
if (--stack_elt < 0)
|
||
internal_error (__FILE__, __LINE__, "execute_stack_op error");
|
||
return stack[stack_elt];
|
||
}
|
||
|
||
static void
|
||
update_context (struct context *context, struct frame_state *fs, int chain)
|
||
{
|
||
struct context *orig_context;
|
||
CORE_ADDR cfa = 0;
|
||
long i;
|
||
|
||
unwind_tmp_obstack_init ();
|
||
|
||
orig_context = context_alloc ();
|
||
context_cpy (orig_context, context);
|
||
|
||
/* Compute this frame's CFA. */
|
||
switch (fs->cfa_how)
|
||
{
|
||
case CFA_REG_OFFSET:
|
||
get_reg ((char *) &cfa, context, fs->cfa_reg);
|
||
cfa += fs->cfa_offset;
|
||
break;
|
||
|
||
case CFA_EXP:
|
||
/* ??? No way of knowing what register number is the stack pointer
|
||
to do the same sort of handling as above. Assume that if the
|
||
CFA calculation is so complicated as to require a stack program
|
||
that this will not be a problem. */
|
||
{
|
||
char *exp = fs->cfa_exp;
|
||
ULONGEST len;
|
||
|
||
len = read_uleb128 (fs->objfile->obfd, &exp);
|
||
cfa = (CORE_ADDR) execute_stack_op (fs->objfile, exp,
|
||
exp + len, context, 0);
|
||
break;
|
||
}
|
||
default:
|
||
break;
|
||
}
|
||
context->cfa = cfa;
|
||
|
||
if (!chain)
|
||
orig_context->cfa = cfa;
|
||
|
||
/* Compute the addresses of all registers saved in this frame. */
|
||
for (i = 0; i < NUM_REGS; ++i)
|
||
switch (fs->regs.reg[i].how)
|
||
{
|
||
case REG_UNSAVED:
|
||
if (i == SP_REGNUM)
|
||
{
|
||
context->reg[i].how = REG_CTX_VALUE;
|
||
context->reg[i].loc.addr = cfa;
|
||
}
|
||
else
|
||
context->reg[i].how = REG_CTX_UNSAVED;
|
||
break;
|
||
case REG_SAVED_OFFSET:
|
||
context->reg[i].how = REG_CTX_SAVED_OFFSET;
|
||
context->reg[i].loc.offset = fs->regs.reg[i].loc.offset;
|
||
break;
|
||
case REG_SAVED_REG:
|
||
switch (orig_context->reg[fs->regs.reg[i].loc.reg].how)
|
||
{
|
||
case REG_CTX_UNSAVED:
|
||
context->reg[i].how = REG_CTX_UNSAVED;
|
||
break;
|
||
case REG_CTX_SAVED_OFFSET:
|
||
context->reg[i].how = REG_CTX_SAVED_OFFSET;
|
||
context->reg[i].loc.offset = orig_context->cfa - context->cfa +
|
||
orig_context->reg[fs->regs.reg[i].loc.reg].loc.offset;
|
||
break;
|
||
case REG_CTX_SAVED_REG:
|
||
context->reg[i].how = REG_CTX_SAVED_REG;
|
||
context->reg[i].loc.reg =
|
||
orig_context->reg[fs->regs.reg[i].loc.reg].loc.reg;
|
||
break;
|
||
case REG_CTX_SAVED_ADDR:
|
||
context->reg[i].how = REG_CTX_SAVED_ADDR;
|
||
context->reg[i].loc.addr =
|
||
orig_context->reg[fs->regs.reg[i].loc.reg].loc.addr;
|
||
break;
|
||
default:
|
||
internal_error (__FILE__, __LINE__, "bad switch");
|
||
}
|
||
break;
|
||
case REG_SAVED_EXP:
|
||
{
|
||
char *exp = fs->regs.reg[i].loc.exp;
|
||
ULONGEST len;
|
||
CORE_ADDR val;
|
||
|
||
len = read_uleb128 (fs->objfile->obfd, &exp);
|
||
val = execute_stack_op (fs->objfile, exp, exp + len,
|
||
orig_context, cfa);
|
||
context->reg[i].how = REG_CTX_SAVED_ADDR;
|
||
context->reg[i].loc.addr = val;
|
||
}
|
||
break;
|
||
default:
|
||
internal_error (__FILE__, __LINE__, "bad switch");
|
||
}
|
||
get_reg ((char *) &context->ra, context, fs->retaddr_column);
|
||
unwind_tmp_obstack_free ();
|
||
}
|
||
|
||
static int
|
||
is_cie (ULONGEST cie_id, int dwarf64)
|
||
{
|
||
return dwarf64 ? (cie_id == 0xffffffffffffffff) : (cie_id == 0xffffffff);
|
||
}
|
||
|
||
static int
|
||
compare_fde_unit (const void *a, const void *b)
|
||
{
|
||
struct fde_unit **first, **second;
|
||
first = (struct fde_unit **) a;
|
||
second = (struct fde_unit **) b;
|
||
if ((*first)->initial_location > (*second)->initial_location)
|
||
return 1;
|
||
else if ((*first)->initial_location < (*second)->initial_location)
|
||
return -1;
|
||
else
|
||
return 0;
|
||
}
|
||
|
||
/* Build the cie_chunks and fde_chunks tables from informations
|
||
found in .debug_frame and .eh_frame sections. */
|
||
/* We can handle both of these sections almost in the same way, however there
|
||
are some exceptions:
|
||
- CIE ID is -1 in debug_frame, but 0 in eh_frame
|
||
- eh_frame may contain some more information that are used only by gcc
|
||
(eg. personality pointer, LSDA pointer, ...). Most of them we can ignore.
|
||
- In debug_frame FDE's item cie_id contains offset of it's parent CIE.
|
||
In eh_frame FDE's item cie_id is a relative pointer to the parent CIE.
|
||
Anyway we don't need to bother with this, because we are smart enough
|
||
to keep the pointer to the parent CIE of oncomming FDEs in 'last_cie'.
|
||
- Although debug_frame items can contain Augmentation as well as
|
||
eh_frame ones, I have never seen them non-empty. Thus only in eh_frame
|
||
we can encounter for example non-absolute pointers (Aug. 'R').
|
||
-- mludvig */
|
||
static void
|
||
parse_frame_info (struct objfile *objfile, file_ptr frame_offset,
|
||
unsigned int frame_size, int eh_frame)
|
||
{
|
||
bfd *abfd = objfile->obfd;
|
||
asection *curr_section_ptr;
|
||
char *start = NULL;
|
||
char *end = NULL;
|
||
char *frame_buffer = NULL;
|
||
char *curr_section_name, *aug_data;
|
||
struct cie_unit *last_cie = NULL;
|
||
int last_dup_fde = 0;
|
||
int aug_len, i;
|
||
CORE_ADDR curr_section_vma = 0;
|
||
|
||
unwind_tmp_obstack_init ();
|
||
|
||
frame_buffer = dwarf2_read_section (objfile, frame_offset, frame_size);
|
||
|
||
start = frame_buffer;
|
||
end = frame_buffer + frame_size;
|
||
|
||
curr_section_name = eh_frame ? ".eh_frame" : ".debug_frame";
|
||
curr_section_ptr = bfd_get_section_by_name (abfd, curr_section_name);
|
||
if (curr_section_ptr)
|
||
curr_section_vma = curr_section_ptr->vma;
|
||
|
||
if (start)
|
||
{
|
||
while (start < end)
|
||
{
|
||
unsigned long length;
|
||
ULONGEST cie_id;
|
||
ULONGEST unit_offset = start - frame_buffer;
|
||
int bytes_read, dwarf64;
|
||
char *block_end;
|
||
|
||
length = read_initial_length (abfd, start, &bytes_read);
|
||
start += bytes_read;
|
||
dwarf64 = (bytes_read == 12);
|
||
block_end = start + length;
|
||
|
||
if (length == 0)
|
||
{
|
||
start = block_end;
|
||
continue;
|
||
}
|
||
|
||
cie_id = read_length (abfd, start, &bytes_read, dwarf64);
|
||
start += bytes_read;
|
||
|
||
if ((eh_frame && cie_id == 0) || is_cie (cie_id, dwarf64))
|
||
{
|
||
struct cie_unit *cie = cie_unit_alloc ();
|
||
char *aug;
|
||
|
||
cie->objfile = objfile;
|
||
cie->next = cie_chunks;
|
||
cie_chunks = cie;
|
||
|
||
cie->objfile = objfile;
|
||
|
||
cie->offset = unit_offset;
|
||
|
||
start++; /* version */
|
||
|
||
cie->augmentation = aug = start;
|
||
while (*start++); /* Skips last NULL as well */
|
||
|
||
cie->code_align = read_uleb128 (abfd, &start);
|
||
cie->data_align = read_sleb128 (abfd, &start);
|
||
cie->ra = read_1u (abfd, &start);
|
||
|
||
/* Augmentation:
|
||
z Indicates that a uleb128 is present to size the
|
||
augmentation section.
|
||
L Indicates the encoding (and thus presence) of
|
||
an LSDA pointer in the FDE augmentation.
|
||
R Indicates a non-default pointer encoding for
|
||
FDE code pointers.
|
||
P Indicates the presence of an encoding + language
|
||
personality routine in the CIE augmentation.
|
||
|
||
[This info comes from GCC's dwarf2out.c]
|
||
*/
|
||
if (*aug == 'z')
|
||
{
|
||
aug_len = read_uleb128 (abfd, &start);
|
||
aug_data = start;
|
||
start += aug_len;
|
||
++aug;
|
||
}
|
||
|
||
cie->data = start;
|
||
cie->data_length = block_end - cie->data;
|
||
|
||
while (*aug != '\0')
|
||
{
|
||
if (aug[0] == 'e' && aug[1] == 'h')
|
||
{
|
||
aug_data += sizeof (void *);
|
||
aug++;
|
||
}
|
||
else if (aug[0] == 'R')
|
||
cie->addr_encoding = *aug_data++;
|
||
else if (aug[0] == 'P')
|
||
{
|
||
CORE_ADDR pers_addr;
|
||
int pers_addr_enc;
|
||
|
||
pers_addr_enc = *aug_data++;
|
||
/* We don't need pers_addr value and so we
|
||
don't care about it's encoding. */
|
||
pers_addr = read_encoded_pointer (abfd, &aug_data,
|
||
pers_addr_enc);
|
||
}
|
||
else if (aug[0] == 'L' && eh_frame)
|
||
{
|
||
int lsda_addr_enc;
|
||
|
||
/* Perhaps we should save this to CIE for later use?
|
||
Do we need it for something in GDB? */
|
||
lsda_addr_enc = *aug_data++;
|
||
}
|
||
else
|
||
warning ("CFI warning: unknown augmentation \"%c\""
|
||
" in \"%s\" of\n"
|
||
"\t%s", aug[0], curr_section_name,
|
||
objfile->name);
|
||
aug++;
|
||
}
|
||
|
||
last_cie = cie;
|
||
}
|
||
else
|
||
{
|
||
struct fde_unit *fde;
|
||
struct cie_unit *cie;
|
||
int dup = 0;
|
||
CORE_ADDR init_loc;
|
||
|
||
/* We assume that debug_frame is in order
|
||
CIE,FDE,CIE,FDE,FDE,... and thus the CIE for this FDE
|
||
should be stored in last_cie pointer. If not, we'll
|
||
try to find it by the older way. */
|
||
if (last_cie)
|
||
cie = last_cie;
|
||
else
|
||
{
|
||
warning ("CFI: last_cie == NULL. "
|
||
"Perhaps a malformed %s section in '%s'...?\n",
|
||
curr_section_name, objfile->name);
|
||
|
||
cie = cie_chunks;
|
||
while (cie)
|
||
{
|
||
if (cie->objfile == objfile)
|
||
{
|
||
if (eh_frame &&
|
||
(cie->offset ==
|
||
(unit_offset + bytes_read - cie_id)))
|
||
break;
|
||
if (!eh_frame && (cie->offset == cie_id))
|
||
break;
|
||
}
|
||
|
||
cie = cie->next;
|
||
}
|
||
if (!cie)
|
||
error ("CFI: can't find CIE pointer");
|
||
}
|
||
|
||
init_loc = read_encoded_pointer (abfd, &start,
|
||
cie->addr_encoding);
|
||
|
||
switch (pointer_encoding (cie->addr_encoding))
|
||
{
|
||
case PE_absptr:
|
||
break;
|
||
case PE_pcrel:
|
||
/* start-frame_buffer gives offset from
|
||
the beginning of actual section. */
|
||
init_loc += curr_section_vma + start - frame_buffer;
|
||
break;
|
||
default:
|
||
warning ("CFI: Unsupported pointer encoding\n");
|
||
}
|
||
|
||
/* For relocatable objects we must add an offset telling
|
||
where the section is actually mapped in the memory. */
|
||
init_loc += ANOFFSET (objfile->section_offsets,
|
||
SECT_OFF_TEXT (objfile));
|
||
|
||
/* If we have both .debug_frame and .eh_frame present in
|
||
a file, we must eliminate duplicate FDEs. For now we'll
|
||
run through all entries in fde_chunks and check it one
|
||
by one. Perhaps in the future we can implement a faster
|
||
searching algorithm. */
|
||
/* eh_frame==2 indicates, that this file has an already
|
||
parsed .debug_frame too. When eh_frame==1 it means, that no
|
||
.debug_frame is present and thus we don't need to check for
|
||
duplicities. eh_frame==0 means, that we parse .debug_frame
|
||
and don't need to care about duplicate FDEs, because
|
||
.debug_frame is parsed first. */
|
||
if (eh_frame == 2)
|
||
for (i = 0; eh_frame == 2 && i < fde_chunks.elems; i++)
|
||
{
|
||
/* We assume that FDEs in .debug_frame and .eh_frame
|
||
have the same order (if they are present, of course).
|
||
If we find a duplicate entry for one FDE and save
|
||
it's index to last_dup_fde it's very likely, that
|
||
we'll find an entry for the following FDE right after
|
||
the previous one. Thus in many cases we'll run this
|
||
loop only once. */
|
||
last_dup_fde = (last_dup_fde + i) % fde_chunks.elems;
|
||
if (fde_chunks.array[last_dup_fde]->initial_location
|
||
== init_loc)
|
||
{
|
||
dup = 1;
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* Allocate a new entry only if this FDE isn't a duplicate of
|
||
something we have already seen. */
|
||
if (!dup)
|
||
{
|
||
fde_chunks_need_space ();
|
||
fde = fde_unit_alloc ();
|
||
|
||
fde_chunks.array[fde_chunks.elems++] = fde;
|
||
|
||
fde->initial_location = init_loc;
|
||
fde->address_range = read_encoded_pointer (abfd, &start,
|
||
cie->
|
||
addr_encoding);
|
||
|
||
fde->cie_ptr = cie;
|
||
|
||
/* Here we intentionally ignore augmentation data
|
||
from FDE, because we don't need them. */
|
||
if (cie->augmentation[0] == 'z')
|
||
start += read_uleb128 (abfd, &start);
|
||
|
||
fde->data = start;
|
||
fde->data_length = block_end - start;
|
||
}
|
||
}
|
||
start = block_end;
|
||
}
|
||
qsort (fde_chunks.array, fde_chunks.elems,
|
||
sizeof (struct fde_unit *), compare_fde_unit);
|
||
}
|
||
}
|
||
|
||
/* We must parse both .debug_frame section and .eh_frame because
|
||
* not all frames must be present in both of these sections. */
|
||
void
|
||
dwarf2_build_frame_info (struct objfile *objfile)
|
||
{
|
||
int after_debug_frame = 0;
|
||
|
||
/* If we have .debug_frame then the parser is called with
|
||
eh_frame==0 for .debug_frame and eh_frame==2 for .eh_frame,
|
||
otherwise it's only called once for .eh_frame with argument
|
||
eh_frame==1. */
|
||
|
||
if (dwarf_frame_offset)
|
||
{
|
||
parse_frame_info (objfile, dwarf_frame_offset,
|
||
dwarf_frame_size, 0 /* = debug_frame */ );
|
||
after_debug_frame = 1;
|
||
}
|
||
|
||
if (dwarf_eh_frame_offset)
|
||
parse_frame_info (objfile, dwarf_eh_frame_offset, dwarf_eh_frame_size,
|
||
1 /* = eh_frame */ + after_debug_frame);
|
||
}
|
||
|
||
/* Return the frame address. */
|
||
CORE_ADDR
|
||
cfi_read_fp (void)
|
||
{
|
||
struct context *context;
|
||
struct frame_state *fs;
|
||
CORE_ADDR cfa;
|
||
|
||
unwind_tmp_obstack_init ();
|
||
|
||
context = context_alloc ();
|
||
fs = frame_state_alloc ();
|
||
|
||
context->ra = read_pc () + 1;
|
||
|
||
frame_state_for (context, fs);
|
||
update_context (context, fs, 0);
|
||
|
||
cfa = context->cfa;
|
||
|
||
unwind_tmp_obstack_free ();
|
||
|
||
return cfa;
|
||
}
|
||
|
||
/* Store the frame address. This function is not used. */
|
||
|
||
void
|
||
cfi_write_fp (CORE_ADDR val)
|
||
{
|
||
struct context *context;
|
||
struct frame_state *fs;
|
||
|
||
unwind_tmp_obstack_init ();
|
||
|
||
context = context_alloc ();
|
||
fs = frame_state_alloc ();
|
||
|
||
context->ra = read_pc () + 1;
|
||
|
||
frame_state_for (context, fs);
|
||
|
||
if (fs->cfa_how == CFA_REG_OFFSET)
|
||
{
|
||
val -= fs->cfa_offset;
|
||
deprecated_write_register_gen (fs->cfa_reg, (char *) &val);
|
||
}
|
||
else
|
||
warning ("Can't write fp.");
|
||
|
||
unwind_tmp_obstack_free ();
|
||
}
|
||
|
||
/* Restore the machine to the state it had before the current frame
|
||
was created. */
|
||
void
|
||
cfi_pop_frame (struct frame_info *fi)
|
||
{
|
||
char *regbuf = alloca (MAX_REGISTER_RAW_SIZE);
|
||
int regnum;
|
||
|
||
for (regnum = 0; regnum < NUM_REGS; regnum++)
|
||
{
|
||
get_reg (regbuf, UNWIND_CONTEXT (fi), regnum);
|
||
deprecated_write_register_bytes (REGISTER_BYTE (regnum), regbuf,
|
||
REGISTER_RAW_SIZE (regnum));
|
||
}
|
||
write_register (PC_REGNUM, UNWIND_CONTEXT (fi)->ra);
|
||
|
||
flush_cached_frames ();
|
||
}
|
||
|
||
/* Determine the address of the calling function's frame. */
|
||
CORE_ADDR
|
||
cfi_frame_chain (struct frame_info *fi)
|
||
{
|
||
struct context *context;
|
||
struct frame_state *fs;
|
||
CORE_ADDR cfa;
|
||
|
||
unwind_tmp_obstack_init ();
|
||
|
||
context = context_alloc ();
|
||
fs = frame_state_alloc ();
|
||
context_cpy (context, UNWIND_CONTEXT (fi));
|
||
|
||
/* outermost frame */
|
||
if (context->ra == 0)
|
||
{
|
||
unwind_tmp_obstack_free ();
|
||
return 0;
|
||
}
|
||
|
||
frame_state_for (context, fs);
|
||
update_context (context, fs, 1);
|
||
|
||
cfa = context->cfa;
|
||
unwind_tmp_obstack_free ();
|
||
|
||
return cfa;
|
||
}
|
||
|
||
/* Sets the pc of the frame. */
|
||
CORE_ADDR
|
||
cfi_init_frame_pc (int fromleaf, struct frame_info *fi)
|
||
{
|
||
if (get_next_frame (fi))
|
||
{
|
||
CORE_ADDR pc;
|
||
/* FIXME: cagney/2002-12-04: This is straight wrong. It's
|
||
assuming that the PC is CORE_ADDR (a host quantity) in size. */
|
||
get_reg ((void *)&pc, UNWIND_CONTEXT (get_next_frame (fi)), PC_REGNUM);
|
||
return pc;
|
||
}
|
||
else
|
||
return read_pc ();
|
||
}
|
||
|
||
/* Initialize unwind context informations of the frame. */
|
||
void
|
||
cfi_init_extra_frame_info (int fromleaf, struct frame_info *fi)
|
||
{
|
||
struct frame_state *fs;
|
||
|
||
unwind_tmp_obstack_init ();
|
||
|
||
fs = frame_state_alloc ();
|
||
deprecated_set_frame_context (fi, frame_obstack_alloc (sizeof (struct context)));
|
||
UNWIND_CONTEXT (fi)->reg =
|
||
frame_obstack_alloc (sizeof (struct context_reg) * NUM_REGS);
|
||
memset (UNWIND_CONTEXT (fi)->reg, 0,
|
||
sizeof (struct context_reg) * NUM_REGS);
|
||
|
||
if (get_next_frame (fi))
|
||
{
|
||
context_cpy (UNWIND_CONTEXT (fi), UNWIND_CONTEXT (get_next_frame (fi)));
|
||
frame_state_for (UNWIND_CONTEXT (fi), fs);
|
||
update_context (UNWIND_CONTEXT (fi), fs, 1);
|
||
}
|
||
else
|
||
{
|
||
UNWIND_CONTEXT (fi)->ra = get_frame_pc (fi) + 1;
|
||
frame_state_for (UNWIND_CONTEXT (fi), fs);
|
||
update_context (UNWIND_CONTEXT (fi), fs, 0);
|
||
}
|
||
|
||
unwind_tmp_obstack_free ();
|
||
}
|
||
|
||
/* Obtain return address of the frame. */
|
||
CORE_ADDR
|
||
cfi_get_ra (struct frame_info *fi)
|
||
{
|
||
return UNWIND_CONTEXT (fi)->ra;
|
||
}
|
||
|
||
/* Find register number REGNUM relative to FRAME and put its
|
||
(raw) contents in *RAW_BUFFER. Set *OPTIMIZED if the variable
|
||
was optimized out (and thus can't be fetched). If the variable
|
||
was fetched from memory, set *ADDRP to where it was fetched from,
|
||
otherwise it was fetched from a register.
|
||
|
||
The argument RAW_BUFFER must point to aligned memory. */
|
||
void
|
||
cfi_get_saved_register (char *raw_buffer,
|
||
int *optimized,
|
||
CORE_ADDR *addrp,
|
||
struct frame_info *frame,
|
||
int regnum, enum lval_type *lval)
|
||
{
|
||
if (!target_has_registers)
|
||
error ("No registers.");
|
||
|
||
/* Normal systems don't optimize out things with register numbers. */
|
||
if (optimized != NULL)
|
||
*optimized = 0;
|
||
|
||
if (addrp) /* default assumption: not found in memory */
|
||
*addrp = 0;
|
||
|
||
if (!get_next_frame (frame))
|
||
{
|
||
deprecated_read_register_gen (regnum, raw_buffer);
|
||
if (lval != NULL)
|
||
*lval = lval_register;
|
||
if (addrp != NULL)
|
||
*addrp = REGISTER_BYTE (regnum);
|
||
}
|
||
else
|
||
{
|
||
frame = get_next_frame (frame);
|
||
switch (UNWIND_CONTEXT (frame)->reg[regnum].how)
|
||
{
|
||
case REG_CTX_UNSAVED:
|
||
deprecated_read_register_gen (regnum, raw_buffer);
|
||
if (lval != NULL)
|
||
*lval = not_lval;
|
||
if (optimized != NULL)
|
||
*optimized = 1;
|
||
break;
|
||
case REG_CTX_SAVED_OFFSET:
|
||
target_read_memory (UNWIND_CONTEXT (frame)->cfa +
|
||
UNWIND_CONTEXT (frame)->reg[regnum].loc.offset,
|
||
raw_buffer, REGISTER_RAW_SIZE (regnum));
|
||
if (lval != NULL)
|
||
*lval = lval_memory;
|
||
if (addrp != NULL)
|
||
*addrp =
|
||
UNWIND_CONTEXT (frame)->cfa +
|
||
UNWIND_CONTEXT (frame)->reg[regnum].loc.offset;
|
||
break;
|
||
case REG_CTX_SAVED_REG:
|
||
deprecated_read_register_gen (UNWIND_CONTEXT (frame)->reg[regnum].loc.reg,
|
||
raw_buffer);
|
||
if (lval != NULL)
|
||
*lval = lval_register;
|
||
if (addrp != NULL)
|
||
*addrp =
|
||
REGISTER_BYTE (UNWIND_CONTEXT (frame)->reg[regnum].loc.reg);
|
||
break;
|
||
case REG_CTX_SAVED_ADDR:
|
||
target_read_memory (UNWIND_CONTEXT (frame)->reg[regnum].loc.addr,
|
||
raw_buffer, REGISTER_RAW_SIZE (regnum));
|
||
if (lval != NULL)
|
||
*lval = lval_memory;
|
||
if (addrp != NULL)
|
||
*addrp = UNWIND_CONTEXT (frame)->reg[regnum].loc.addr;
|
||
break;
|
||
case REG_CTX_VALUE:
|
||
memcpy (raw_buffer, &UNWIND_CONTEXT (frame)->reg[regnum].loc.addr,
|
||
REGISTER_RAW_SIZE (regnum));
|
||
if (lval != NULL)
|
||
*lval = not_lval;
|
||
if (optimized != NULL)
|
||
*optimized = 0;
|
||
break;
|
||
default:
|
||
internal_error (__FILE__, __LINE__,
|
||
"cfi_get_saved_register: unknown register rule");
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Return the register that the function uses for a frame pointer,
|
||
plus any necessary offset to be applied to the register before
|
||
any frame pointer offsets. */
|
||
void
|
||
cfi_virtual_frame_pointer (CORE_ADDR pc, int *frame_reg,
|
||
LONGEST * frame_offset)
|
||
{
|
||
struct context *context;
|
||
struct frame_state *fs;
|
||
|
||
unwind_tmp_obstack_init ();
|
||
|
||
context = context_alloc ();
|
||
fs = frame_state_alloc ();
|
||
|
||
context->ra = read_pc () + 1;
|
||
|
||
frame_state_for (context, fs);
|
||
|
||
if (fs->cfa_how == CFA_REG_OFFSET)
|
||
{
|
||
*frame_reg = fs->cfa_reg;
|
||
*frame_offset = fs->cfa_offset;
|
||
}
|
||
else
|
||
error ("dwarf cfi error: CFA is not defined as CFA_REG_OFFSET");
|
||
|
||
unwind_tmp_obstack_free ();
|
||
}
|