/* Frame unwinder for frames with DWARF Call Frame Information.
- Copyright 2003, 2004, 2005 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010
+ Free Software Foundation, Inc.
Contributed by Mark Kettenis.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "dwarf2expr.h"
-#include "elf/dwarf2.h"
+#include "dwarf2.h"
#include "frame.h"
#include "frame-base.h"
#include "frame-unwind.h"
#include "symtab.h"
#include "objfiles.h"
#include "regcache.h"
+#include "value.h"
#include "gdb_assert.h"
#include "gdb_string.h"
#include "complaints.h"
#include "dwarf2-frame.h"
+struct comp_unit;
+
/* Call Frame Information (CFI). */
/* Common Information Entry (CIE). */
struct dwarf2_cie
{
+ /* Computation Unit for this CIE. */
+ struct comp_unit *unit;
+
/* Offset into the .debug_frame section where this CIE was found.
Used to identify this CIE. */
ULONGEST cie_pointer;
ULONGEST return_address_register;
/* Instruction sequence to initialize a register set. */
- unsigned char *initial_instructions;
- unsigned char *end;
+ gdb_byte *initial_instructions;
+ gdb_byte *end;
+
+ /* Saved augmentation, in case it's needed later. */
+ char *augmentation;
/* Encoding of addresses. */
- unsigned char encoding;
+ gdb_byte encoding;
+
+ /* Target address size in bytes. */
+ int addr_size;
/* True if a 'z' augmentation existed. */
unsigned char saw_z_augmentation;
- struct dwarf2_cie *next;
+ /* True if an 'S' augmentation existed. */
+ unsigned char signal_frame;
+
+ /* The version recorded in the CIE. */
+ unsigned char version;
+
+ /* The segment size. */
+ unsigned char segment_size;
+};
+
+struct dwarf2_cie_table
+{
+ int num_entries;
+ struct dwarf2_cie **entries;
};
/* Frame Description Entry (FDE). */
CORE_ADDR address_range;
/* Instruction sequence. */
- unsigned char *instructions;
- unsigned char *end;
+ gdb_byte *instructions;
+ gdb_byte *end;
+
+ /* True if this FDE is read from a .eh_frame instead of a .debug_frame
+ section. */
+ unsigned char eh_frame_p;
+};
- struct dwarf2_fde *next;
+struct dwarf2_fde_table
+{
+ int num_entries;
+ struct dwarf2_fde **entries;
+};
+
+/* A minimal decoding of DWARF2 compilation units. We only decode
+ what's needed to get to the call frame information. */
+
+struct comp_unit
+{
+ /* Keep the bfd convenient. */
+ bfd *abfd;
+
+ struct objfile *objfile;
+
+ /* Pointer to the .debug_frame section loaded into memory. */
+ gdb_byte *dwarf_frame_buffer;
+
+ /* Length of the loaded .debug_frame section. */
+ bfd_size_type dwarf_frame_size;
+
+ /* Pointer to the .debug_frame section. */
+ asection *dwarf_frame_section;
+
+ /* Base for DW_EH_PE_datarel encodings. */
+ bfd_vma dbase;
+
+ /* Base for DW_EH_PE_textrel encodings. */
+ bfd_vma tbase;
};
static struct dwarf2_fde *dwarf2_frame_find_fde (CORE_ADDR *pc);
+
+static int dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum,
+ int eh_frame_p);
+
+static CORE_ADDR read_encoded_value (struct comp_unit *unit, gdb_byte encoding,
+ int ptr_len, const gdb_byte *buf,
+ unsigned int *bytes_read_ptr,
+ CORE_ADDR func_base);
\f
/* Structure describing a frame state. */
struct dwarf2_frame_state_reg *reg;
int num_regs;
+ LONGEST cfa_offset;
+ ULONGEST cfa_reg;
+ enum {
+ CFA_UNSET,
+ CFA_REG_OFFSET,
+ CFA_EXP
+ } cfa_how;
+ const gdb_byte *cfa_exp;
+
/* Used to implement DW_CFA_remember_state. */
struct dwarf2_frame_state_reg_info *prev;
} regs;
- LONGEST cfa_offset;
- ULONGEST cfa_reg;
- unsigned char *cfa_exp;
- enum {
- CFA_UNSET,
- CFA_REG_OFFSET,
- CFA_EXP
- } cfa_how;
-
/* The PC described by the current frame state. */
CORE_ADDR pc;
LONGEST data_align;
ULONGEST code_align;
ULONGEST retaddr_column;
+
+ /* Flags for known producer quirks. */
+
+ /* The ARM compilers, in DWARF2 mode, assume that DW_CFA_def_cfa
+ and DW_CFA_def_cfa_offset takes a factored offset. */
+ int armcc_cfa_offsets_sf;
+
+ /* The ARM compilers, in DWARF2 or DWARF3 mode, may assume that
+ the CFA is defined as REG - OFFSET rather than REG + OFFSET. */
+ int armcc_cfa_offsets_reversed;
};
/* Store the length the expression for the CFA in the `cfa_reg' field,
which is unused in that case. */
#define cfa_exp_len cfa_reg
-/* Assert that the register set RS is large enough to store NUM_REGS
+/* Assert that the register set RS is large enough to store gdbarch_num_regs
columns. If necessary, enlarge the register set. */
static void
static CORE_ADDR
read_reg (void *baton, int reg)
{
- struct frame_info *next_frame = (struct frame_info *) baton;
- struct gdbarch *gdbarch = get_frame_arch (next_frame);
+ struct frame_info *this_frame = (struct frame_info *) baton;
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
int regnum;
- char *buf;
+ gdb_byte *buf;
+
+ regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, reg);
- regnum = DWARF2_REG_TO_REGNUM (reg);
+ buf = alloca (register_size (gdbarch, regnum));
+ get_frame_register (this_frame, regnum, buf);
- buf = (char *) alloca (register_size (gdbarch, regnum));
- frame_unwind_register (next_frame, regnum, buf);
- return extract_typed_address (buf, builtin_type_void_data_ptr);
+ /* Convert the register to an integer. This returns a LONGEST
+ rather than a CORE_ADDR, but unpack_pointer does the same thing
+ under the covers, and this makes more sense for non-pointer
+ registers. Maybe read_reg and the associated interfaces should
+ deal with "struct value" instead of CORE_ADDR. */
+ return unpack_long (register_type (gdbarch, regnum), buf);
}
static void
-read_mem (void *baton, char *buf, CORE_ADDR addr, size_t len)
+read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len)
{
read_memory (addr, buf, len);
}
static void
-no_get_frame_base (void *baton, unsigned char **start, size_t *length)
+no_get_frame_base (void *baton, const gdb_byte **start, size_t *length)
{
internal_error (__FILE__, __LINE__,
_("Support for DW_OP_fbreg is unimplemented"));
}
+/* Helper function for execute_stack_op. */
+
+static CORE_ADDR
+no_get_frame_cfa (void *baton)
+{
+ internal_error (__FILE__, __LINE__,
+ _("Support for DW_OP_call_frame_cfa is unimplemented"));
+}
+
static CORE_ADDR
no_get_tls_address (void *baton, CORE_ADDR offset)
{
_("Support for DW_OP_GNU_push_tls_address is unimplemented"));
}
+/* Execute the required actions for both the DW_CFA_restore and
+DW_CFA_restore_extended instructions. */
+static void
+dwarf2_restore_rule (struct gdbarch *gdbarch, ULONGEST reg_num,
+ struct dwarf2_frame_state *fs, int eh_frame_p)
+{
+ ULONGEST reg;
+
+ gdb_assert (fs->initial.reg);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg_num, eh_frame_p);
+ dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+
+ /* Check if this register was explicitly initialized in the
+ CIE initial instructions. If not, default the rule to
+ UNSPECIFIED. */
+ if (reg < fs->initial.num_regs)
+ fs->regs.reg[reg] = fs->initial.reg[reg];
+ else
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNSPECIFIED;
+
+ if (fs->regs.reg[reg].how == DWARF2_FRAME_REG_UNSPECIFIED)
+ complaint (&symfile_complaints, _("\
+incomplete CFI data; DW_CFA_restore unspecified\n\
+register %s (#%d) at %s"),
+ gdbarch_register_name
+ (gdbarch, gdbarch_dwarf2_reg_to_regnum (gdbarch, reg)),
+ gdbarch_dwarf2_reg_to_regnum (gdbarch, reg),
+ paddress (gdbarch, fs->pc));
+}
+
static CORE_ADDR
-execute_stack_op (unsigned char *exp, ULONGEST len,
- struct frame_info *next_frame, CORE_ADDR initial)
+execute_stack_op (const gdb_byte *exp, ULONGEST len, int addr_size,
+ struct frame_info *this_frame, CORE_ADDR initial,
+ int initial_in_stack_memory)
{
struct dwarf_expr_context *ctx;
CORE_ADDR result;
+ struct cleanup *old_chain;
ctx = new_dwarf_expr_context ();
- ctx->baton = next_frame;
+ old_chain = make_cleanup_free_dwarf_expr_context (ctx);
+
+ ctx->gdbarch = get_frame_arch (this_frame);
+ ctx->addr_size = addr_size;
+ ctx->baton = this_frame;
ctx->read_reg = read_reg;
ctx->read_mem = read_mem;
ctx->get_frame_base = no_get_frame_base;
+ ctx->get_frame_cfa = no_get_frame_cfa;
ctx->get_tls_address = no_get_tls_address;
- dwarf_expr_push (ctx, initial);
+ dwarf_expr_push (ctx, initial, initial_in_stack_memory);
dwarf_expr_eval (ctx, exp, len);
result = dwarf_expr_fetch (ctx, 0);
- if (ctx->in_reg)
- result = read_reg (next_frame, result);
+ if (ctx->location == DWARF_VALUE_REGISTER)
+ result = read_reg (this_frame, result);
+ else if (ctx->location != DWARF_VALUE_MEMORY)
+ {
+ /* This is actually invalid DWARF, but if we ever do run across
+ it somehow, we might as well support it. So, instead, report
+ it as unimplemented. */
+ error (_("Not implemented: computing unwound register using explicit value operator"));
+ }
- free_dwarf_expr_context (ctx);
+ do_cleanups (old_chain);
return result;
}
\f
static void
-execute_cfa_program (unsigned char *insn_ptr, unsigned char *insn_end,
- struct frame_info *next_frame,
+execute_cfa_program (struct dwarf2_fde *fde, const gdb_byte *insn_ptr,
+ const gdb_byte *insn_end, struct frame_info *this_frame,
struct dwarf2_frame_state *fs)
{
- CORE_ADDR pc = frame_pc_unwind (next_frame);
+ int eh_frame_p = fde->eh_frame_p;
+ CORE_ADDR pc = get_frame_pc (this_frame);
int bytes_read;
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
while (insn_ptr < insn_end && fs->pc <= pc)
{
- unsigned char insn = *insn_ptr++;
+ gdb_byte insn = *insn_ptr++;
ULONGEST utmp, reg;
LONGEST offset;
else if ((insn & 0xc0) == DW_CFA_offset)
{
reg = insn & 0x3f;
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
offset = utmp * fs->data_align;
dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
}
else if ((insn & 0xc0) == DW_CFA_restore)
{
- gdb_assert (fs->initial.reg);
reg = insn & 0x3f;
- dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
- fs->regs.reg[reg] = fs->initial.reg[reg];
+ dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p);
}
else
{
switch (insn)
{
case DW_CFA_set_loc:
- fs->pc = dwarf2_read_address (insn_ptr, insn_end, &bytes_read);
+ fs->pc = read_encoded_value (fde->cie->unit, fde->cie->encoding,
+ fde->cie->addr_size, insn_ptr,
+ &bytes_read, fde->initial_location);
+ /* Apply the objfile offset for relocatable objects. */
+ fs->pc += ANOFFSET (fde->cie->unit->objfile->section_offsets,
+ SECT_OFF_TEXT (fde->cie->unit->objfile));
insn_ptr += bytes_read;
break;
case DW_CFA_advance_loc1:
- utmp = extract_unsigned_integer (insn_ptr, 1);
+ utmp = extract_unsigned_integer (insn_ptr, 1, byte_order);
fs->pc += utmp * fs->code_align;
insn_ptr++;
break;
case DW_CFA_advance_loc2:
- utmp = extract_unsigned_integer (insn_ptr, 2);
+ utmp = extract_unsigned_integer (insn_ptr, 2, byte_order);
fs->pc += utmp * fs->code_align;
insn_ptr += 2;
break;
case DW_CFA_advance_loc4:
- utmp = extract_unsigned_integer (insn_ptr, 4);
+ utmp = extract_unsigned_integer (insn_ptr, 4, byte_order);
fs->pc += utmp * fs->code_align;
insn_ptr += 4;
break;
case DW_CFA_offset_extended:
insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
offset = utmp * fs->data_align;
dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
break;
case DW_CFA_restore_extended:
- gdb_assert (fs->initial.reg);
insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
- dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
- fs->regs.reg[reg] = fs->initial.reg[reg];
+ dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p);
break;
case DW_CFA_undefined:
insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNDEFINED;
break;
case DW_CFA_same_value:
insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAME_VALUE;
break;
case DW_CFA_register:
insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
+ utmp = dwarf2_frame_adjust_regnum (gdbarch, utmp, eh_frame_p);
dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG;
fs->regs.reg[reg].loc.reg = utmp;
if (old_rs == NULL)
{
complaint (&symfile_complaints, _("\
-bad CFI data; mismatched DW_CFA_restore_state at 0x%s"), paddr (fs->pc));
+bad CFI data; mismatched DW_CFA_restore_state at %s"),
+ paddress (gdbarch, fs->pc));
}
else
{
break;
case DW_CFA_def_cfa:
- insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_reg);
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->regs.cfa_reg);
insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
- fs->cfa_offset = utmp;
- fs->cfa_how = CFA_REG_OFFSET;
+
+ if (fs->armcc_cfa_offsets_sf)
+ utmp *= fs->data_align;
+
+ fs->regs.cfa_offset = utmp;
+ fs->regs.cfa_how = CFA_REG_OFFSET;
break;
case DW_CFA_def_cfa_register:
- insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_reg);
- fs->cfa_how = CFA_REG_OFFSET;
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->regs.cfa_reg);
+ fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch,
+ fs->regs.cfa_reg,
+ eh_frame_p);
+ fs->regs.cfa_how = CFA_REG_OFFSET;
break;
case DW_CFA_def_cfa_offset:
- insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_offset);
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
+
+ if (fs->armcc_cfa_offsets_sf)
+ utmp *= fs->data_align;
+
+ fs->regs.cfa_offset = utmp;
/* cfa_how deliberately not set. */
break;
break;
case DW_CFA_def_cfa_expression:
- insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_exp_len);
- fs->cfa_exp = insn_ptr;
- fs->cfa_how = CFA_EXP;
- insn_ptr += fs->cfa_exp_len;
+ insn_ptr = read_uleb128 (insn_ptr, insn_end,
+ &fs->regs.cfa_exp_len);
+ fs->regs.cfa_exp = insn_ptr;
+ fs->regs.cfa_how = CFA_EXP;
+ insn_ptr += fs->regs.cfa_exp_len;
break;
case DW_CFA_expression:
insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
fs->regs.reg[reg].loc.exp = insn_ptr;
case DW_CFA_offset_extended_sf:
insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset);
offset *= fs->data_align;
dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
fs->regs.reg[reg].loc.offset = offset;
break;
+ case DW_CFA_val_offset:
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
+ offset = utmp * fs->data_align;
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET;
+ fs->regs.reg[reg].loc.offset = offset;
+ break;
+
+ case DW_CFA_val_offset_sf:
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset);
+ offset *= fs->data_align;
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET;
+ fs->regs.reg[reg].loc.offset = offset;
+ break;
+
+ case DW_CFA_val_expression:
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
+ fs->regs.reg[reg].loc.exp = insn_ptr;
+ fs->regs.reg[reg].exp_len = utmp;
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_EXP;
+ insn_ptr += utmp;
+ break;
+
case DW_CFA_def_cfa_sf:
- insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_reg);
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->regs.cfa_reg);
+ fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch,
+ fs->regs.cfa_reg,
+ eh_frame_p);
insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset);
- fs->cfa_offset = offset * fs->data_align;
- fs->cfa_how = CFA_REG_OFFSET;
+ fs->regs.cfa_offset = offset * fs->data_align;
+ fs->regs.cfa_how = CFA_REG_OFFSET;
break;
case DW_CFA_def_cfa_offset_sf:
insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset);
- fs->cfa_offset = offset * fs->data_align;
+ fs->regs.cfa_offset = offset * fs->data_align;
/* cfa_how deliberately not set. */
break;
+ case DW_CFA_GNU_window_save:
+ /* This is SPARC-specific code, and contains hard-coded
+ constants for the register numbering scheme used by
+ GCC. Rather than having a architecture-specific
+ operation that's only ever used by a single
+ architecture, we provide the implementation here.
+ Incidentally that's what GCC does too in its
+ unwinder. */
+ {
+ int size = register_size (gdbarch, 0);
+
+ dwarf2_frame_state_alloc_regs (&fs->regs, 32);
+ for (reg = 8; reg < 16; reg++)
+ {
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG;
+ fs->regs.reg[reg].loc.reg = reg + 16;
+ }
+ for (reg = 16; reg < 32; reg++)
+ {
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET;
+ fs->regs.reg[reg].loc.offset = (reg - 16) * size;
+ }
+ }
+ break;
+
case DW_CFA_GNU_args_size:
/* Ignored. */
insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
break;
+ case DW_CFA_GNU_negative_offset_extended:
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
+ insn_ptr = read_uleb128 (insn_ptr, insn_end, &offset);
+ offset *= fs->data_align;
+ dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET;
+ fs->regs.reg[reg].loc.offset = -offset;
+ break;
+
default:
internal_error (__FILE__, __LINE__, _("Unknown CFI encountered."));
}
struct dwarf2_frame_ops
{
/* Pre-initialize the register state REG for register REGNUM. */
- void (*init_reg) (struct gdbarch *, int, struct dwarf2_frame_state_reg *);
+ void (*init_reg) (struct gdbarch *, int, struct dwarf2_frame_state_reg *,
+ struct frame_info *);
- /* Check whether the frame preceding NEXT_FRAME will be a signal
- trampoline. */
+ /* Check whether the THIS_FRAME is a signal trampoline. */
int (*signal_frame_p) (struct gdbarch *, struct frame_info *);
+
+ /* Convert .eh_frame register number to DWARF register number, or
+ adjust .debug_frame register number. */
+ int (*adjust_regnum) (struct gdbarch *, int, int);
};
/* Default architecture-specific register state initialization
static void
dwarf2_frame_default_init_reg (struct gdbarch *gdbarch, int regnum,
- struct dwarf2_frame_state_reg *reg)
+ struct dwarf2_frame_state_reg *reg,
+ struct frame_info *this_frame)
{
/* If we have a register that acts as a program counter, mark it as
a destination for the return address. If we have a register that
(e.g. IBM S/390 and zSeries). Those architectures should provide
their own architecture-specific initialization function. */
- if (regnum == PC_REGNUM)
+ if (regnum == gdbarch_pc_regnum (gdbarch))
reg->how = DWARF2_FRAME_REG_RA;
- else if (regnum == SP_REGNUM)
+ else if (regnum == gdbarch_sp_regnum (gdbarch))
reg->how = DWARF2_FRAME_REG_CFA;
}
void
dwarf2_frame_set_init_reg (struct gdbarch *gdbarch,
void (*init_reg) (struct gdbarch *, int,
- struct dwarf2_frame_state_reg *))
+ struct dwarf2_frame_state_reg *,
+ struct frame_info *))
{
struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data);
static void
dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum,
- struct dwarf2_frame_state_reg *reg)
+ struct dwarf2_frame_state_reg *reg,
+ struct frame_info *this_frame)
{
struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data);
- ops->init_reg (gdbarch, regnum, reg);
+ ops->init_reg (gdbarch, regnum, reg, this_frame);
}
/* Set the architecture-specific signal trampoline recognition
}
/* Query the architecture-specific signal frame recognizer for
- NEXT_FRAME. */
+ THIS_FRAME. */
static int
dwarf2_frame_signal_frame_p (struct gdbarch *gdbarch,
- struct frame_info *next_frame)
+ struct frame_info *this_frame)
{
struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data);
if (ops->signal_frame_p == NULL)
return 0;
- return ops->signal_frame_p (gdbarch, next_frame);
+ return ops->signal_frame_p (gdbarch, this_frame);
+}
+
+/* Set the architecture-specific adjustment of .eh_frame and .debug_frame
+ register numbers. */
+
+void
+dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch,
+ int (*adjust_regnum) (struct gdbarch *,
+ int, int))
+{
+ struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data);
+
+ ops->adjust_regnum = adjust_regnum;
+}
+
+/* Translate a .eh_frame register to DWARF register, or adjust a .debug_frame
+ register. */
+
+static int
+dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, int eh_frame_p)
+{
+ struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data);
+
+ if (ops->adjust_regnum == NULL)
+ return regnum;
+ return ops->adjust_regnum (gdbarch, regnum, eh_frame_p);
+}
+
+static void
+dwarf2_frame_find_quirks (struct dwarf2_frame_state *fs,
+ struct dwarf2_fde *fde)
+{
+ struct symtab *s;
+
+ s = find_pc_symtab (fs->pc);
+ if (s == NULL)
+ return;
+
+ if (producer_is_realview (s->producer))
+ {
+ if (fde->cie->version == 1)
+ fs->armcc_cfa_offsets_sf = 1;
+
+ if (fde->cie->version == 1)
+ fs->armcc_cfa_offsets_reversed = 1;
+
+ /* The reversed offset problem is present in some compilers
+ using DWARF3, but it was eventually fixed. Check the ARM
+ defined augmentations, which are in the format "armcc" followed
+ by a list of one-character options. The "+" option means
+ this problem is fixed (no quirk needed). If the armcc
+ augmentation is missing, the quirk is needed. */
+ if (fde->cie->version == 3
+ && (strncmp (fde->cie->augmentation, "armcc", 5) != 0
+ || strchr (fde->cie->augmentation + 5, '+') == NULL))
+ fs->armcc_cfa_offsets_reversed = 1;
+
+ return;
+ }
}
\f
/* DWARF Call Frame Address. */
CORE_ADDR cfa;
+ /* Set if the return address column was marked as undefined. */
+ int undefined_retaddr;
+
/* Saved registers, indexed by GDB register number, not by DWARF
register number. */
struct dwarf2_frame_state_reg *reg;
/* Return address register. */
struct dwarf2_frame_state_reg retaddr_reg;
+
+ /* Target address size in bytes. */
+ int addr_size;
};
static struct dwarf2_frame_cache *
-dwarf2_frame_cache (struct frame_info *next_frame, void **this_cache)
+dwarf2_frame_cache (struct frame_info *this_frame, void **this_cache)
{
struct cleanup *old_chain;
- struct gdbarch *gdbarch = get_frame_arch (next_frame);
- const int num_regs = NUM_REGS + NUM_PSEUDO_REGS;
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ const int num_regs = gdbarch_num_regs (gdbarch)
+ + gdbarch_num_pseudo_regs (gdbarch);
struct dwarf2_frame_cache *cache;
struct dwarf2_frame_state *fs;
struct dwarf2_fde *fde;
/* Unwind the PC.
- Note that if NEXT_FRAME is never supposed to return (i.e. a call
+ Note that if the next frame is never supposed to return (i.e. a call
to abort), the compiler might optimize away the instruction at
- NEXT_FRAME's return address. As a result the return address will
+ its return address. As a result the return address will
point at some random instruction, and the CFI for that
instruction is probably worthless to us. GCC's unwinder solves
this problem by substracting 1 from the return address to get an
instruction in the associated delay slot). This should only be
done for "normal" frames and not for resume-type frames (signal
handlers, sentinel frames, dummy frames). The function
- frame_unwind_address_in_block does just this. It's not clear how
+ get_frame_address_in_block does just this. It's not clear how
reliable the method is though; there is the potential for the
register state pre-call being different to that on return. */
- fs->pc = frame_unwind_address_in_block (next_frame);
+ fs->pc = get_frame_address_in_block (this_frame);
/* Find the correct FDE. */
fde = dwarf2_frame_find_fde (&fs->pc);
fs->data_align = fde->cie->data_alignment_factor;
fs->code_align = fde->cie->code_alignment_factor;
fs->retaddr_column = fde->cie->return_address_register;
+ cache->addr_size = fde->cie->addr_size;
+
+ /* Check for "quirks" - known bugs in producers. */
+ dwarf2_frame_find_quirks (fs, fde);
/* First decode all the insns in the CIE. */
- execute_cfa_program (fde->cie->initial_instructions,
- fde->cie->end, next_frame, fs);
+ execute_cfa_program (fde, fde->cie->initial_instructions,
+ fde->cie->end, this_frame, fs);
/* Save the initialized register set. */
fs->initial = fs->regs;
fs->initial.reg = dwarf2_frame_state_copy_regs (&fs->regs);
/* Then decode the insns in the FDE up to our target PC. */
- execute_cfa_program (fde->instructions, fde->end, next_frame, fs);
+ execute_cfa_program (fde, fde->instructions, fde->end, this_frame, fs);
- /* Caclulate the CFA. */
- switch (fs->cfa_how)
+ /* Calculate the CFA. */
+ switch (fs->regs.cfa_how)
{
case CFA_REG_OFFSET:
- cache->cfa = read_reg (next_frame, fs->cfa_reg);
- cache->cfa += fs->cfa_offset;
+ cache->cfa = read_reg (this_frame, fs->regs.cfa_reg);
+ if (fs->armcc_cfa_offsets_reversed)
+ cache->cfa -= fs->regs.cfa_offset;
+ else
+ cache->cfa += fs->regs.cfa_offset;
break;
case CFA_EXP:
cache->cfa =
- execute_stack_op (fs->cfa_exp, fs->cfa_exp_len, next_frame, 0);
+ execute_stack_op (fs->regs.cfa_exp, fs->regs.cfa_exp_len,
+ cache->addr_size, this_frame, 0, 0);
break;
default:
int regnum;
for (regnum = 0; regnum < num_regs; regnum++)
- dwarf2_frame_init_reg (gdbarch, regnum, &cache->reg[regnum]);
+ dwarf2_frame_init_reg (gdbarch, regnum, &cache->reg[regnum], this_frame);
}
/* Go through the DWARF2 CFI generated table and save its register
return address column; it's perfectly all right for it to
correspond to a real register. If it doesn't correspond to a
real register, or if we shouldn't treat it as such,
- DWARF2_REG_TO_REGNUM should be defined to return a number outside
- the range [0, NUM_REGS). */
+ gdbarch_dwarf2_reg_to_regnum should be defined to return a number outside
+ the range [0, gdbarch_num_regs). */
{
int column; /* CFI speak for "register number". */
for (column = 0; column < fs->regs.num_regs; column++)
{
/* Use the GDB register number as the destination index. */
- int regnum = DWARF2_REG_TO_REGNUM (column);
+ int regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, column);
/* If there's no corresponding GDB register, ignore it. */
if (regnum < 0 || regnum >= num_regs)
{
if (cache->reg[regnum].how == DWARF2_FRAME_REG_UNSPECIFIED)
complaint (&symfile_complaints, _("\
-incomplete CFI data; unspecified registers (e.g., %s) at 0x%s"),
+incomplete CFI data; unspecified registers (e.g., %s) at %s"),
gdbarch_register_name (gdbarch, regnum),
- paddr_nz (fs->pc));
+ paddress (gdbarch, fs->pc));
}
else
cache->reg[regnum] = fs->regs.reg[column];
}
}
+ if (fs->retaddr_column < fs->regs.num_regs
+ && fs->regs.reg[fs->retaddr_column].how == DWARF2_FRAME_REG_UNDEFINED)
+ cache->undefined_retaddr = 1;
+
do_cleanups (old_chain);
*this_cache = cache;
}
static void
-dwarf2_frame_this_id (struct frame_info *next_frame, void **this_cache,
+dwarf2_frame_this_id (struct frame_info *this_frame, void **this_cache,
struct frame_id *this_id)
{
struct dwarf2_frame_cache *cache =
- dwarf2_frame_cache (next_frame, this_cache);
+ dwarf2_frame_cache (this_frame, this_cache);
+
+ if (cache->undefined_retaddr)
+ return;
- (*this_id) = frame_id_build (cache->cfa, frame_func_unwind (next_frame));
+ (*this_id) = frame_id_build (cache->cfa, get_frame_func (this_frame));
}
-static void
-dwarf2_frame_prev_register (struct frame_info *next_frame, void **this_cache,
- int regnum, int *optimizedp,
- enum lval_type *lvalp, CORE_ADDR *addrp,
- int *realnump, void *valuep)
+static struct value *
+dwarf2_frame_prev_register (struct frame_info *this_frame, void **this_cache,
+ int regnum)
{
- struct gdbarch *gdbarch = get_frame_arch (next_frame);
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
struct dwarf2_frame_cache *cache =
- dwarf2_frame_cache (next_frame, this_cache);
+ dwarf2_frame_cache (this_frame, this_cache);
+ CORE_ADDR addr;
+ int realnum;
switch (cache->reg[regnum].how)
{
case DWARF2_FRAME_REG_UNDEFINED:
/* If CFI explicitly specified that the value isn't defined,
mark it as optimized away; the value isn't available. */
- *optimizedp = 1;
- *lvalp = not_lval;
- *addrp = 0;
- *realnump = -1;
- if (valuep)
- {
- /* In some cases, for example %eflags on the i386, we have
- to provide a sane value, even though this register wasn't
- saved. Assume we can get it from NEXT_FRAME. */
- frame_unwind_register (next_frame, regnum, valuep);
- }
- break;
+ return frame_unwind_got_optimized (this_frame, regnum);
case DWARF2_FRAME_REG_SAVED_OFFSET:
- *optimizedp = 0;
- *lvalp = lval_memory;
- *addrp = cache->cfa + cache->reg[regnum].loc.offset;
- *realnump = -1;
- if (valuep)
- {
- /* Read the value in from memory. */
- read_memory (*addrp, valuep, register_size (gdbarch, regnum));
- }
- break;
+ addr = cache->cfa + cache->reg[regnum].loc.offset;
+ return frame_unwind_got_memory (this_frame, regnum, addr);
case DWARF2_FRAME_REG_SAVED_REG:
- *optimizedp = 0;
- *lvalp = lval_register;
- *addrp = 0;
- *realnump = DWARF2_REG_TO_REGNUM (cache->reg[regnum].loc.reg);
- if (valuep)
- frame_unwind_register (next_frame, (*realnump), valuep);
- break;
+ realnum
+ = gdbarch_dwarf2_reg_to_regnum (gdbarch, cache->reg[regnum].loc.reg);
+ return frame_unwind_got_register (this_frame, regnum, realnum);
case DWARF2_FRAME_REG_SAVED_EXP:
- *optimizedp = 0;
- *lvalp = lval_memory;
- *addrp = execute_stack_op (cache->reg[regnum].loc.exp,
- cache->reg[regnum].exp_len,
- next_frame, cache->cfa);
- *realnump = -1;
- if (valuep)
- {
- /* Read the value in from memory. */
- read_memory (*addrp, valuep, register_size (gdbarch, regnum));
- }
- break;
+ addr = execute_stack_op (cache->reg[regnum].loc.exp,
+ cache->reg[regnum].exp_len,
+ cache->addr_size, this_frame, cache->cfa, 1);
+ return frame_unwind_got_memory (this_frame, regnum, addr);
+
+ case DWARF2_FRAME_REG_SAVED_VAL_OFFSET:
+ addr = cache->cfa + cache->reg[regnum].loc.offset;
+ return frame_unwind_got_constant (this_frame, regnum, addr);
+
+ case DWARF2_FRAME_REG_SAVED_VAL_EXP:
+ addr = execute_stack_op (cache->reg[regnum].loc.exp,
+ cache->reg[regnum].exp_len,
+ cache->addr_size, this_frame, cache->cfa, 1);
+ return frame_unwind_got_constant (this_frame, regnum, addr);
case DWARF2_FRAME_REG_UNSPECIFIED:
/* GCC, in its infinite wisdom decided to not provide unwind
"undefined"). Code above issues a complaint about this.
Here just fudge the books, assume GCC, and that the value is
more inner on the stack. */
- *optimizedp = 0;
- *lvalp = lval_register;
- *addrp = 0;
- *realnump = regnum;
- if (valuep)
- frame_unwind_register (next_frame, (*realnump), valuep);
- break;
+ return frame_unwind_got_register (this_frame, regnum, regnum);
case DWARF2_FRAME_REG_SAME_VALUE:
- *optimizedp = 0;
- *lvalp = lval_register;
- *addrp = 0;
- *realnump = regnum;
- if (valuep)
- frame_unwind_register (next_frame, (*realnump), valuep);
- break;
+ return frame_unwind_got_register (this_frame, regnum, regnum);
case DWARF2_FRAME_REG_CFA:
- *optimizedp = 0;
- *lvalp = not_lval;
- *addrp = 0;
- *realnump = -1;
- if (valuep)
- {
- /* Store the value. */
- store_typed_address (valuep, builtin_type_void_data_ptr, cache->cfa);
- }
- break;
+ return frame_unwind_got_address (this_frame, regnum, cache->cfa);
+
+ case DWARF2_FRAME_REG_CFA_OFFSET:
+ addr = cache->cfa + cache->reg[regnum].loc.offset;
+ return frame_unwind_got_address (this_frame, regnum, addr);
case DWARF2_FRAME_REG_RA_OFFSET:
- *optimizedp = 0;
- *lvalp = not_lval;
- *addrp = 0;
- *realnump = -1;
- if (valuep)
- {
- CORE_ADDR pc = cache->reg[regnum].loc.offset;
+ addr = cache->reg[regnum].loc.offset;
+ regnum = gdbarch_dwarf2_reg_to_regnum
+ (gdbarch, cache->retaddr_reg.loc.reg);
+ addr += get_frame_register_unsigned (this_frame, regnum);
+ return frame_unwind_got_address (this_frame, regnum, addr);
- regnum = DWARF2_REG_TO_REGNUM (cache->retaddr_reg.loc.reg);
- pc += frame_unwind_register_unsigned (next_frame, regnum);
- store_typed_address (valuep, builtin_type_void_func_ptr, pc);
- }
- break;
+ case DWARF2_FRAME_REG_FN:
+ return cache->reg[regnum].loc.fn (this_frame, this_cache, regnum);
default:
internal_error (__FILE__, __LINE__, _("Unknown register rule."));
}
}
+static int
+dwarf2_frame_sniffer (const struct frame_unwind *self,
+ struct frame_info *this_frame, void **this_cache)
+{
+ /* Grab an address that is guarenteed to reside somewhere within the
+ function. get_frame_pc(), with a no-return next function, can
+ end up returning something past the end of this function's body.
+ If the frame we're sniffing for is a signal frame whose start
+ address is placed on the stack by the OS, its FDE must
+ extend one byte before its start address or we could potentially
+ select the FDE of the previous function. */
+ CORE_ADDR block_addr = get_frame_address_in_block (this_frame);
+ struct dwarf2_fde *fde = dwarf2_frame_find_fde (&block_addr);
+
+ if (!fde)
+ return 0;
+
+ /* On some targets, signal trampolines may have unwind information.
+ We need to recognize them so that we set the frame type
+ correctly. */
+
+ if (fde->cie->signal_frame
+ || dwarf2_frame_signal_frame_p (get_frame_arch (this_frame),
+ this_frame))
+ return self->type == SIGTRAMP_FRAME;
+
+ return self->type != SIGTRAMP_FRAME;
+}
+
static const struct frame_unwind dwarf2_frame_unwind =
{
NORMAL_FRAME,
dwarf2_frame_this_id,
- dwarf2_frame_prev_register
+ dwarf2_frame_prev_register,
+ NULL,
+ dwarf2_frame_sniffer
};
static const struct frame_unwind dwarf2_signal_frame_unwind =
{
SIGTRAMP_FRAME,
dwarf2_frame_this_id,
- dwarf2_frame_prev_register
+ dwarf2_frame_prev_register,
+ NULL,
+ dwarf2_frame_sniffer
};
-const struct frame_unwind *
-dwarf2_frame_sniffer (struct frame_info *next_frame)
-{
- /* Grab an address that is guarenteed to reside somewhere within the
- function. frame_pc_unwind(), for a no-return next function, can
- end up returning something past the end of this function's body. */
- CORE_ADDR block_addr = frame_unwind_address_in_block (next_frame);
- if (!dwarf2_frame_find_fde (&block_addr))
- return NULL;
+/* Append the DWARF-2 frame unwinders to GDBARCH's list. */
- /* On some targets, signal trampolines may have unwind information.
- We need to recognize them so that we set the frame type
- correctly. */
-
- if (dwarf2_frame_signal_frame_p (get_frame_arch (next_frame),
- next_frame))
- return &dwarf2_signal_frame_unwind;
-
- return &dwarf2_frame_unwind;
+void
+dwarf2_append_unwinders (struct gdbarch *gdbarch)
+{
+ frame_unwind_append_unwinder (gdbarch, &dwarf2_frame_unwind);
+ frame_unwind_append_unwinder (gdbarch, &dwarf2_signal_frame_unwind);
}
\f
response to the "info frame" command. */
static CORE_ADDR
-dwarf2_frame_base_address (struct frame_info *next_frame, void **this_cache)
+dwarf2_frame_base_address (struct frame_info *this_frame, void **this_cache)
{
struct dwarf2_frame_cache *cache =
- dwarf2_frame_cache (next_frame, this_cache);
+ dwarf2_frame_cache (this_frame, this_cache);
return cache->cfa;
}
};
const struct frame_base *
-dwarf2_frame_base_sniffer (struct frame_info *next_frame)
+dwarf2_frame_base_sniffer (struct frame_info *this_frame)
{
- CORE_ADDR pc = frame_pc_unwind (next_frame);
- if (dwarf2_frame_find_fde (&pc))
+ CORE_ADDR block_addr = get_frame_address_in_block (this_frame);
+
+ if (dwarf2_frame_find_fde (&block_addr))
return &dwarf2_frame_base;
return NULL;
}
-\f
-/* A minimal decoding of DWARF2 compilation units. We only decode
- what's needed to get to the call frame information. */
-
-struct comp_unit
-{
- /* Keep the bfd convenient. */
- bfd *abfd;
-
- struct objfile *objfile;
-
- /* Linked list of CIEs for this object. */
- struct dwarf2_cie *cie;
-
- /* Pointer to the .debug_frame section loaded into memory. */
- char *dwarf_frame_buffer;
-
- /* Length of the loaded .debug_frame section. */
- unsigned long dwarf_frame_size;
-
- /* Pointer to the .debug_frame section. */
- asection *dwarf_frame_section;
- /* Base for DW_EH_PE_datarel encodings. */
- bfd_vma dbase;
-
- /* Base for DW_EH_PE_textrel encodings. */
- bfd_vma tbase;
-};
+/* Compute the CFA for THIS_FRAME, but only if THIS_FRAME came from
+ the DWARF unwinder. This is used to implement
+ DW_OP_call_frame_cfa. */
+CORE_ADDR
+dwarf2_frame_cfa (struct frame_info *this_frame)
+{
+ while (get_frame_type (this_frame) == INLINE_FRAME)
+ this_frame = get_prev_frame (this_frame);
+ /* This restriction could be lifted if other unwinders are known to
+ compute the frame base in a way compatible with the DWARF
+ unwinder. */
+ if (! frame_unwinder_is (this_frame, &dwarf2_frame_unwind))
+ error (_("can't compute CFA for this frame"));
+ return get_frame_base (this_frame);
+}
+\f
const struct objfile_data *dwarf2_frame_objfile_data;
static unsigned int
-read_1_byte (bfd *bfd, char *buf)
+read_1_byte (bfd *abfd, gdb_byte *buf)
{
- return bfd_get_8 (abfd, (bfd_byte *) buf);
+ return bfd_get_8 (abfd, buf);
}
static unsigned int
-read_4_bytes (bfd *abfd, char *buf)
+read_4_bytes (bfd *abfd, gdb_byte *buf)
{
- return bfd_get_32 (abfd, (bfd_byte *) buf);
+ return bfd_get_32 (abfd, buf);
}
static ULONGEST
-read_8_bytes (bfd *abfd, char *buf)
+read_8_bytes (bfd *abfd, gdb_byte *buf)
{
- return bfd_get_64 (abfd, (bfd_byte *) buf);
+ return bfd_get_64 (abfd, buf);
}
static ULONGEST
-read_unsigned_leb128 (bfd *abfd, char *buf, unsigned int *bytes_read_ptr)
+read_unsigned_leb128 (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr)
{
ULONGEST result;
unsigned int num_read;
int shift;
- unsigned char byte;
+ gdb_byte byte;
result = 0;
shift = 0;
}
static LONGEST
-read_signed_leb128 (bfd *abfd, char *buf, unsigned int *bytes_read_ptr)
+read_signed_leb128 (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr)
{
LONGEST result;
int shift;
unsigned int num_read;
- unsigned char byte;
+ gdb_byte byte;
result = 0;
shift = 0;
}
while (byte & 0x80);
- if ((shift < 32) && (byte & 0x40))
- result |= -(1 << shift);
+ if (shift < 8 * sizeof (result) && (byte & 0x40))
+ result |= -(((LONGEST)1) << shift);
*bytes_read_ptr = num_read;
}
static ULONGEST
-read_initial_length (bfd *abfd, char *buf, unsigned int *bytes_read_ptr)
+read_initial_length (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr)
{
LONGEST result;
- result = bfd_get_32 (abfd, (bfd_byte *) buf);
+ result = bfd_get_32 (abfd, buf);
if (result == 0xffffffff)
{
- result = bfd_get_64 (abfd, (bfd_byte *) buf + 4);
+ result = bfd_get_64 (abfd, buf + 4);
*bytes_read_ptr = 12;
}
else
position in the FDE, ...). Bit 7, indicates that the address
should be dereferenced. */
-static unsigned char
+static gdb_byte
encoding_for_size (unsigned int size)
{
switch (size)
}
}
-static unsigned int
-size_of_encoded_value (unsigned char encoding)
-{
- if (encoding == DW_EH_PE_omit)
- return 0;
-
- switch (encoding & 0x07)
- {
- case DW_EH_PE_absptr:
- return TYPE_LENGTH (builtin_type_void_data_ptr);
- case DW_EH_PE_udata2:
- return 2;
- case DW_EH_PE_udata4:
- return 4;
- case DW_EH_PE_udata8:
- return 8;
- default:
- internal_error (__FILE__, __LINE__, _("Invalid or unsupported encoding"));
- }
-}
-
static CORE_ADDR
-read_encoded_value (struct comp_unit *unit, unsigned char encoding,
- unsigned char *buf, unsigned int *bytes_read_ptr)
+read_encoded_value (struct comp_unit *unit, gdb_byte encoding,
+ int ptr_len, const gdb_byte *buf,
+ unsigned int *bytes_read_ptr,
+ CORE_ADDR func_base)
{
- int ptr_len = size_of_encoded_value (DW_EH_PE_absptr);
ptrdiff_t offset;
CORE_ADDR base;
base = 0;
break;
case DW_EH_PE_pcrel:
- base = bfd_get_section_vma (unit->bfd, unit->dwarf_frame_section);
- base += ((char *) buf - unit->dwarf_frame_buffer);
+ base = bfd_get_section_vma (unit->abfd, unit->dwarf_frame_section);
+ base += (buf - unit->dwarf_frame_buffer);
break;
case DW_EH_PE_datarel:
base = unit->dbase;
base = unit->tbase;
break;
case DW_EH_PE_funcrel:
- /* FIXME: kettenis/20040501: For now just pretend
- DW_EH_PE_funcrel is equivalent to DW_EH_PE_absptr. For
- reading the initial location of an FDE it should be treated
- as such, and currently that's the only place where this code
- is used. */
- base = 0;
+ base = func_base;
break;
case DW_EH_PE_aligned:
base = 0;
- offset = (char *) buf - unit->dwarf_frame_buffer;
+ offset = buf - unit->dwarf_frame_buffer;
if ((offset % ptr_len) != 0)
{
*bytes_read_ptr = ptr_len - (offset % ptr_len);
}
if ((encoding & 0x07) == 0x00)
- encoding |= encoding_for_size (ptr_len);
+ {
+ encoding |= encoding_for_size (ptr_len);
+ if (bfd_get_sign_extend_vma (unit->abfd))
+ encoding |= DW_EH_PE_signed;
+ }
switch (encoding & 0x0f)
{
case DW_EH_PE_uleb128:
{
ULONGEST value;
- unsigned char *end_buf = buf + (sizeof (value) + 1) * 8 / 7;
+ const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7;
+
*bytes_read_ptr += read_uleb128 (buf, end_buf, &value) - buf;
return base + value;
}
case DW_EH_PE_sleb128:
{
LONGEST value;
- char *end_buf = buf + (sizeof (value) + 1) * 8 / 7;
+ const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7;
+
*bytes_read_ptr += read_sleb128 (buf, end_buf, &value) - buf;
return base + value;
}
}
\f
-/* GCC uses a single CIE for all FDEs in a .debug_frame section.
- That's why we use a simple linked list here. */
+static int
+bsearch_cie_cmp (const void *key, const void *element)
+{
+ ULONGEST cie_pointer = *(ULONGEST *) key;
+ struct dwarf2_cie *cie = *(struct dwarf2_cie **) element;
+
+ if (cie_pointer == cie->cie_pointer)
+ return 0;
+ return (cie_pointer < cie->cie_pointer) ? -1 : 1;
+}
+
+/* Find CIE with the given CIE_POINTER in CIE_TABLE. */
static struct dwarf2_cie *
-find_cie (struct comp_unit *unit, ULONGEST cie_pointer)
+find_cie (struct dwarf2_cie_table *cie_table, ULONGEST cie_pointer)
{
- struct dwarf2_cie *cie = unit->cie;
+ struct dwarf2_cie **p_cie;
- while (cie)
+ /* The C standard (ISO/IEC 9899:TC2) requires the BASE argument to
+ bsearch be non-NULL. */
+ if (cie_table->entries == NULL)
{
- if (cie->cie_pointer == cie_pointer)
- return cie;
-
- cie = cie->next;
+ gdb_assert (cie_table->num_entries == 0);
+ return NULL;
}
+ p_cie = bsearch (&cie_pointer, cie_table->entries, cie_table->num_entries,
+ sizeof (cie_table->entries[0]), bsearch_cie_cmp);
+ if (p_cie != NULL)
+ return *p_cie;
return NULL;
}
+/* Add a pointer to new CIE to the CIE_TABLE, allocating space for it. */
static void
-add_cie (struct comp_unit *unit, struct dwarf2_cie *cie)
+add_cie (struct dwarf2_cie_table *cie_table, struct dwarf2_cie *cie)
+{
+ const int n = cie_table->num_entries;
+
+ gdb_assert (n < 1
+ || cie_table->entries[n - 1]->cie_pointer < cie->cie_pointer);
+
+ cie_table->entries =
+ xrealloc (cie_table->entries, (n + 1) * sizeof (cie_table->entries[0]));
+ cie_table->entries[n] = cie;
+ cie_table->num_entries = n + 1;
+}
+
+static int
+bsearch_fde_cmp (const void *key, const void *element)
{
- cie->next = unit->cie;
- unit->cie = cie;
+ CORE_ADDR seek_pc = *(CORE_ADDR *) key;
+ struct dwarf2_fde *fde = *(struct dwarf2_fde **) element;
+
+ if (seek_pc < fde->initial_location)
+ return -1;
+ if (seek_pc < fde->initial_location + fde->address_range)
+ return 0;
+ return 1;
}
/* Find the FDE for *PC. Return a pointer to the FDE, and store the
ALL_OBJFILES (objfile)
{
- struct dwarf2_fde *fde;
+ struct dwarf2_fde_table *fde_table;
+ struct dwarf2_fde **p_fde;
CORE_ADDR offset;
+ CORE_ADDR seek_pc;
- fde = objfile_data (objfile, dwarf2_frame_objfile_data);
- if (fde == NULL)
+ fde_table = objfile_data (objfile, dwarf2_frame_objfile_data);
+ if (fde_table == NULL)
+ {
+ dwarf2_build_frame_info (objfile);
+ fde_table = objfile_data (objfile, dwarf2_frame_objfile_data);
+ }
+ gdb_assert (fde_table != NULL);
+
+ if (fde_table->num_entries == 0)
continue;
gdb_assert (objfile->section_offsets);
offset = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));
- while (fde)
- {
- if (*pc >= fde->initial_location + offset
- && *pc < fde->initial_location + offset + fde->address_range)
- {
- *pc = fde->initial_location + offset;
- return fde;
- }
+ gdb_assert (fde_table->num_entries > 0);
+ if (*pc < offset + fde_table->entries[0]->initial_location)
+ continue;
- fde = fde->next;
- }
+ seek_pc = *pc - offset;
+ p_fde = bsearch (&seek_pc, fde_table->entries, fde_table->num_entries,
+ sizeof (fde_table->entries[0]), bsearch_fde_cmp);
+ if (p_fde != NULL)
+ {
+ *pc = (*p_fde)->initial_location + offset;
+ return *p_fde;
+ }
}
-
return NULL;
}
+/* Add a pointer to new FDE to the FDE_TABLE, allocating space for it. */
static void
-add_fde (struct comp_unit *unit, struct dwarf2_fde *fde)
+add_fde (struct dwarf2_fde_table *fde_table, struct dwarf2_fde *fde)
{
- fde->next = objfile_data (unit->objfile, dwarf2_frame_objfile_data);
- set_objfile_data (unit->objfile, dwarf2_frame_objfile_data, fde);
+ if (fde->address_range == 0)
+ /* Discard useless FDEs. */
+ return;
+
+ fde_table->num_entries += 1;
+ fde_table->entries =
+ xrealloc (fde_table->entries,
+ fde_table->num_entries * sizeof (fde_table->entries[0]));
+ fde_table->entries[fde_table->num_entries - 1] = fde;
}
#ifdef CC_HAS_LONG_LONG
#define DW64_CIE_ID ~0
#endif
-static char *decode_frame_entry (struct comp_unit *unit, char *start,
- int eh_frame_p);
+static gdb_byte *decode_frame_entry (struct comp_unit *unit, gdb_byte *start,
+ int eh_frame_p,
+ struct dwarf2_cie_table *cie_table,
+ struct dwarf2_fde_table *fde_table);
/* Decode the next CIE or FDE. Return NULL if invalid input, otherwise
the next byte to be processed. */
-static char *
-decode_frame_entry_1 (struct comp_unit *unit, char *start, int eh_frame_p)
+static gdb_byte *
+decode_frame_entry_1 (struct comp_unit *unit, gdb_byte *start, int eh_frame_p,
+ struct dwarf2_cie_table *cie_table,
+ struct dwarf2_fde_table *fde_table)
{
- char *buf;
+ struct gdbarch *gdbarch = get_objfile_arch (unit->objfile);
+ gdb_byte *buf, *end;
LONGEST length;
unsigned int bytes_read;
int dwarf64_p;
ULONGEST cie_id;
ULONGEST cie_pointer;
- char *end;
buf = start;
length = read_initial_length (unit->abfd, buf, &bytes_read);
cie_pointer = start - unit->dwarf_frame_buffer;
/* Check whether we've already read it. */
- if (find_cie (unit, cie_pointer))
+ if (find_cie (cie_table, cie_pointer))
return end;
cie = (struct dwarf2_cie *)
depends on the target address size. */
cie->encoding = DW_EH_PE_absptr;
+ /* The target address size. For .eh_frame FDEs this is considered
+ equal to the size of a target pointer. For .dwarf_frame FDEs,
+ this is supposed to be the target address size from the associated
+ CU header. FIXME: We do not have a good way to determine the
+ latter. Always use the target pointer size for now. */
+ cie->addr_size = gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT;
+
+ /* We'll determine the final value later, but we need to
+ initialize it conservatively. */
+ cie->signal_frame = 0;
+
/* Check version number. */
cie_version = read_1_byte (unit->abfd, buf);
- if (cie_version != 1 && cie_version != 3)
+ if (cie_version != 1 && cie_version != 3 && cie_version != 4)
return NULL;
+ cie->version = cie_version;
buf += 1;
/* Interpret the interesting bits of the augmentation. */
- augmentation = buf;
- buf = augmentation + strlen (augmentation) + 1;
+ cie->augmentation = augmentation = (char *) buf;
+ buf += (strlen (augmentation) + 1);
+
+ /* Ignore armcc augmentations. We only use them for quirks,
+ and that doesn't happen until later. */
+ if (strncmp (augmentation, "armcc", 5) == 0)
+ augmentation += strlen (augmentation);
/* The GCC 2.x "eh" augmentation has a pointer immediately
following the augmentation string, so it must be handled
if (augmentation[0] == 'e' && augmentation[1] == 'h')
{
/* Skip. */
- buf += TYPE_LENGTH (builtin_type_void_data_ptr);
+ buf += gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT;
augmentation += 2;
}
+ if (cie->version >= 4)
+ {
+ /* FIXME: check that this is the same as from the CU header. */
+ cie->addr_size = read_1_byte (unit->abfd, buf);
+ ++buf;
+ cie->segment_size = read_1_byte (unit->abfd, buf);
+ ++buf;
+ }
+ else
+ {
+ cie->addr_size = gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT;
+ cie->segment_size = 0;
+ }
+
cie->code_alignment_factor =
read_unsigned_leb128 (unit->abfd, buf, &bytes_read);
buf += bytes_read;
else
cie->return_address_register = read_unsigned_leb128 (unit->abfd, buf,
&bytes_read);
+ cie->return_address_register
+ = dwarf2_frame_adjust_regnum (gdbarch,
+ cie->return_address_register,
+ eh_frame_p);
+
buf += bytes_read;
cie->saw_z_augmentation = (*augmentation == 'z');
else if (*augmentation == 'P')
{
/* Skip. Avoid indirection since we throw away the result. */
- unsigned char encoding = (*buf++) & ~DW_EH_PE_indirect;
- read_encoded_value (unit, encoding, buf, &bytes_read);
+ gdb_byte encoding = (*buf++) & ~DW_EH_PE_indirect;
+ read_encoded_value (unit, encoding, cie->addr_size,
+ buf, &bytes_read, 0);
buf += bytes_read;
augmentation++;
}
- /* Otherwise we have an unknown augmentation.
- Bail out unless we saw a 'z' prefix. */
- else
+ /* "S" indicates a signal frame, such that the return
+ address must not be decremented to locate the call frame
+ info for the previous frame; it might even be the first
+ instruction of a function, so decrementing it would take
+ us to a different function. */
+ else if (*augmentation == 'S')
{
- if (cie->initial_instructions == NULL)
- return end;
+ cie->signal_frame = 1;
+ augmentation++;
+ }
- /* Skip unknown augmentations. */
- buf = cie->initial_instructions;
+ /* Otherwise we have an unknown augmentation. Assume that either
+ there is no augmentation data, or we saw a 'z' prefix. */
+ else
+ {
+ if (cie->initial_instructions)
+ buf = cie->initial_instructions;
break;
}
}
cie->initial_instructions = buf;
cie->end = end;
+ cie->unit = unit;
- add_cie (unit, cie);
+ add_cie (cie_table, cie);
}
else
{
fde = (struct dwarf2_fde *)
obstack_alloc (&unit->objfile->objfile_obstack,
sizeof (struct dwarf2_fde));
- fde->cie = find_cie (unit, cie_pointer);
+ fde->cie = find_cie (cie_table, cie_pointer);
if (fde->cie == NULL)
{
decode_frame_entry (unit, unit->dwarf_frame_buffer + cie_pointer,
- eh_frame_p);
- fde->cie = find_cie (unit, cie_pointer);
+ eh_frame_p, cie_table, fde_table);
+ fde->cie = find_cie (cie_table, cie_pointer);
}
gdb_assert (fde->cie != NULL);
fde->initial_location =
- read_encoded_value (unit, fde->cie->encoding, buf, &bytes_read);
+ read_encoded_value (unit, fde->cie->encoding, fde->cie->addr_size,
+ buf, &bytes_read, 0);
buf += bytes_read;
fde->address_range =
- read_encoded_value (unit, fde->cie->encoding & 0x0f, buf, &bytes_read);
+ read_encoded_value (unit, fde->cie->encoding & 0x0f,
+ fde->cie->addr_size, buf, &bytes_read, 0);
buf += bytes_read;
/* A 'z' augmentation in the CIE implies the presence of an
fde->instructions = buf;
fde->end = end;
- add_fde (unit, fde);
+ fde->eh_frame_p = eh_frame_p;
+
+ add_fde (fde_table, fde);
}
return end;
}
/* Read a CIE or FDE in BUF and decode it. */
-static char *
-decode_frame_entry (struct comp_unit *unit, char *start, int eh_frame_p)
+static gdb_byte *
+decode_frame_entry (struct comp_unit *unit, gdb_byte *start, int eh_frame_p,
+ struct dwarf2_cie_table *cie_table,
+ struct dwarf2_fde_table *fde_table)
{
enum { NONE, ALIGN4, ALIGN8, FAIL } workaround = NONE;
- char *ret;
- const char *msg;
+ gdb_byte *ret;
ptrdiff_t start_offset;
while (1)
{
- ret = decode_frame_entry_1 (unit, start, eh_frame_p);
+ ret = decode_frame_entry_1 (unit, start, eh_frame_p,
+ cie_table, fde_table);
if (ret != NULL)
break;
}
\f
-/* FIXME: kettenis/20030504: This still needs to be integrated with
- dwarf2read.c in a better way. */
-
/* Imported from dwarf2read.c. */
-extern asection *dwarf_frame_section;
-extern asection *dwarf_eh_frame_section;
+extern void dwarf2_get_section_info (struct objfile *, const char *, asection **,
+ gdb_byte **, bfd_size_type *);
-/* Imported from dwarf2read.c. */
-extern char *dwarf2_read_section (struct objfile *objfile, asection *sectp);
+static int
+qsort_fde_cmp (const void *a, const void *b)
+{
+ struct dwarf2_fde *aa = *(struct dwarf2_fde **)a;
+ struct dwarf2_fde *bb = *(struct dwarf2_fde **)b;
+
+ if (aa->initial_location == bb->initial_location)
+ {
+ if (aa->address_range != bb->address_range
+ && aa->eh_frame_p == 0 && bb->eh_frame_p == 0)
+ /* Linker bug, e.g. gold/10400.
+ Work around it by keeping stable sort order. */
+ return (a < b) ? -1 : 1;
+ else
+ /* Put eh_frame entries after debug_frame ones. */
+ return aa->eh_frame_p - bb->eh_frame_p;
+ }
+
+ return (aa->initial_location < bb->initial_location) ? -1 : 1;
+}
void
dwarf2_build_frame_info (struct objfile *objfile)
{
- struct comp_unit unit;
- char *frame_ptr;
+ struct comp_unit *unit;
+ gdb_byte *frame_ptr;
+ struct dwarf2_cie_table cie_table;
+ struct dwarf2_fde_table fde_table;
+ struct dwarf2_fde_table *fde_table2;
+
+ cie_table.num_entries = 0;
+ cie_table.entries = NULL;
+
+ fde_table.num_entries = 0;
+ fde_table.entries = NULL;
/* Build a minimal decoding of the DWARF2 compilation unit. */
- unit.abfd = objfile->obfd;
- unit.objfile = objfile;
- unit.dbase = 0;
- unit.tbase = 0;
-
- /* First add the information from the .eh_frame section. That way,
- the FDEs from that section are searched last. */
- if (dwarf_eh_frame_section)
+ unit = (struct comp_unit *) obstack_alloc (&objfile->objfile_obstack,
+ sizeof (struct comp_unit));
+ unit->abfd = objfile->obfd;
+ unit->objfile = objfile;
+ unit->dbase = 0;
+ unit->tbase = 0;
+
+ dwarf2_get_section_info (objfile, ".eh_frame",
+ &unit->dwarf_frame_section,
+ &unit->dwarf_frame_buffer,
+ &unit->dwarf_frame_size);
+ if (unit->dwarf_frame_size)
{
asection *got, *txt;
- unit.cie = NULL;
- unit.dwarf_frame_buffer = dwarf2_read_section (objfile,
- dwarf_eh_frame_section);
-
- unit.dwarf_frame_size = bfd_get_section_size (dwarf_eh_frame_section);
- unit.dwarf_frame_section = dwarf_eh_frame_section;
-
/* FIXME: kettenis/20030602: This is the DW_EH_PE_datarel base
that is used for the i386/amd64 target, which currently is
the only target in GCC that supports/uses the
DW_EH_PE_datarel encoding. */
- got = bfd_get_section_by_name (unit.abfd, ".got");
+ got = bfd_get_section_by_name (unit->abfd, ".got");
if (got)
- unit.dbase = got->vma;
+ unit->dbase = got->vma;
/* GCC emits the DW_EH_PE_textrel encoding type on sh and ia64
so far. */
- txt = bfd_get_section_by_name (unit.abfd, ".text");
+ txt = bfd_get_section_by_name (unit->abfd, ".text");
if (txt)
- unit.tbase = txt->vma;
+ unit->tbase = txt->vma;
+
+ frame_ptr = unit->dwarf_frame_buffer;
+ while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size)
+ frame_ptr = decode_frame_entry (unit, frame_ptr, 1,
+ &cie_table, &fde_table);
+
+ if (cie_table.num_entries != 0)
+ {
+ /* Reinit cie_table: debug_frame has different CIEs. */
+ xfree (cie_table.entries);
+ cie_table.num_entries = 0;
+ cie_table.entries = NULL;
+ }
+ }
- frame_ptr = unit.dwarf_frame_buffer;
- while (frame_ptr < unit.dwarf_frame_buffer + unit.dwarf_frame_size)
- frame_ptr = decode_frame_entry (&unit, frame_ptr, 1);
+ dwarf2_get_section_info (objfile, ".debug_frame",
+ &unit->dwarf_frame_section,
+ &unit->dwarf_frame_buffer,
+ &unit->dwarf_frame_size);
+ if (unit->dwarf_frame_size)
+ {
+ frame_ptr = unit->dwarf_frame_buffer;
+ while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size)
+ frame_ptr = decode_frame_entry (unit, frame_ptr, 0,
+ &cie_table, &fde_table);
}
- if (dwarf_frame_section)
+ /* Discard the cie_table, it is no longer needed. */
+ if (cie_table.num_entries != 0)
+ {
+ xfree (cie_table.entries);
+ cie_table.entries = NULL; /* Paranoia. */
+ cie_table.num_entries = 0; /* Paranoia. */
+ }
+
+ /* Copy fde_table to obstack: it is needed at runtime. */
+ fde_table2 = (struct dwarf2_fde_table *)
+ obstack_alloc (&objfile->objfile_obstack, sizeof (*fde_table2));
+
+ if (fde_table.num_entries == 0)
{
- unit.cie = NULL;
- unit.dwarf_frame_buffer = dwarf2_read_section (objfile,
- dwarf_frame_section);
- unit.dwarf_frame_size = bfd_get_section_size (dwarf_frame_section);
- unit.dwarf_frame_section = dwarf_frame_section;
-
- frame_ptr = unit.dwarf_frame_buffer;
- while (frame_ptr < unit.dwarf_frame_buffer + unit.dwarf_frame_size)
- frame_ptr = decode_frame_entry (&unit, frame_ptr, 0);
+ fde_table2->entries = NULL;
+ fde_table2->num_entries = 0;
}
+ else
+ {
+ struct dwarf2_fde *fde_prev = NULL;
+ struct dwarf2_fde *first_non_zero_fde = NULL;
+ int i;
+
+ /* Prepare FDE table for lookups. */
+ qsort (fde_table.entries, fde_table.num_entries,
+ sizeof (fde_table.entries[0]), qsort_fde_cmp);
+
+ /* Check for leftovers from --gc-sections. The GNU linker sets
+ the relevant symbols to zero, but doesn't zero the FDE *end*
+ ranges because there's no relocation there. It's (offset,
+ length), not (start, end). On targets where address zero is
+ just another valid address this can be a problem, since the
+ FDEs appear to be non-empty in the output --- we could pick
+ out the wrong FDE. To work around this, when overlaps are
+ detected, we prefer FDEs that do not start at zero.
+
+ Start by finding the first FDE with non-zero start. Below
+ we'll discard all FDEs that start at zero and overlap this
+ one. */
+ for (i = 0; i < fde_table.num_entries; i++)
+ {
+ struct dwarf2_fde *fde = fde_table.entries[i];
+
+ if (fde->initial_location != 0)
+ {
+ first_non_zero_fde = fde;
+ break;
+ }
+ }
+
+ /* Since we'll be doing bsearch, squeeze out identical (except
+ for eh_frame_p) fde entries so bsearch result is predictable.
+ Also discard leftovers from --gc-sections. */
+ fde_table2->num_entries = 0;
+ for (i = 0; i < fde_table.num_entries; i++)
+ {
+ struct dwarf2_fde *fde = fde_table.entries[i];
+
+ if (fde->initial_location == 0
+ && first_non_zero_fde != NULL
+ && (first_non_zero_fde->initial_location
+ < fde->initial_location + fde->address_range))
+ continue;
+
+ if (fde_prev != NULL
+ && fde_prev->initial_location == fde->initial_location)
+ continue;
+
+ obstack_grow (&objfile->objfile_obstack, &fde_table.entries[i],
+ sizeof (fde_table.entries[0]));
+ ++fde_table2->num_entries;
+ fde_prev = fde;
+ }
+ fde_table2->entries = obstack_finish (&objfile->objfile_obstack);
+
+ /* Discard the original fde_table. */
+ xfree (fde_table.entries);
+ }
+
+ set_objfile_data (objfile, dwarf2_frame_objfile_data, fde_table2);
}
/* Provide a prototype to silence -Wmissing-prototypes. */