/* Frame unwinder for frames with DWARF Call Frame Information.
- Copyright 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 2003-2019 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 "gdb_assert.h"
-#include "gdb_string.h"
+#include "value.h"
+#include "record.h"
#include "complaints.h"
#include "dwarf2-frame.h"
+#include "dwarf2read.h"
+#include "ax.h"
+#include "dwarf2loc.h"
+#include "dwarf2-frame-tailcall.h"
+#include "gdbsupport/gdb_binary_search.h"
+#if GDB_SELF_TEST
+#include "gdbsupport/selftest.h"
+#include "selftest-arch.h"
+#endif
+#include <unordered_map>
+
+#include <algorithm>
+
+struct comp_unit;
/* Call Frame Information (CFI). */
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;
+ const gdb_byte *initial_instructions;
+ const 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;
+
+ /* Target pointer size in bytes. */
+ int ptr_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;
};
+/* The CIE table is used to find CIEs during parsing, but then
+ discarded. It maps from the CIE's offset to the CIE. */
+typedef std::unordered_map<ULONGEST, dwarf2_cie *> dwarf2_cie_table;
+
/* Frame Description Entry (FDE). */
struct dwarf2_fde
CORE_ADDR address_range;
/* Instruction sequence. */
- unsigned char *instructions;
- unsigned char *end;
+ const gdb_byte *instructions;
+ const gdb_byte *end;
- struct dwarf2_fde *next;
+ /* True if this FDE is read from a .eh_frame instead of a .debug_frame
+ section. */
+ unsigned char eh_frame_p;
};
-static struct dwarf2_fde *dwarf2_frame_find_fde (CORE_ADDR *pc);
-\f
-
-/* Structure describing a frame state. */
-
-struct dwarf2_frame_state
+struct dwarf2_fde_table
{
- /* Each register save state can be described in terms of a CFA slot,
- another register, or a location expression. */
- struct dwarf2_frame_state_reg_info
- {
- struct dwarf2_frame_state_reg *reg;
- int num_regs;
-
- /* 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;
-
- /* Initial register set from the CIE.
- Used to implement DW_CFA_restore. */
- struct dwarf2_frame_state_reg_info initial;
-
- /* The information we care about from the CIE. */
- LONGEST data_align;
- ULONGEST code_align;
- ULONGEST retaddr_column;
+ int num_entries;
+ struct dwarf2_fde **entries;
};
-/* 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
- columns. If necessary, enlarge the register set. */
+/* A minimal decoding of DWARF2 compilation units. We only decode
+ what's needed to get to the call frame information. */
-static void
-dwarf2_frame_state_alloc_regs (struct dwarf2_frame_state_reg_info *rs,
- int num_regs)
+struct comp_unit
{
- size_t size = sizeof (struct dwarf2_frame_state_reg);
+ /* Keep the bfd convenient. */
+ bfd *abfd;
- if (num_regs <= rs->num_regs)
- return;
+ struct objfile *objfile;
- rs->reg = (struct dwarf2_frame_state_reg *)
- xrealloc (rs->reg, num_regs * size);
+ /* Pointer to the .debug_frame section loaded into memory. */
+ const gdb_byte *dwarf_frame_buffer;
- /* Initialize newly allocated registers. */
- memset (rs->reg + rs->num_regs, 0, (num_regs - rs->num_regs) * size);
- rs->num_regs = num_regs;
-}
+ /* Length of the loaded .debug_frame section. */
+ bfd_size_type dwarf_frame_size;
-/* Copy the register columns in register set RS into newly allocated
- memory and return a pointer to this newly created copy. */
+ /* Pointer to the .debug_frame section. */
+ asection *dwarf_frame_section;
-static struct dwarf2_frame_state_reg *
-dwarf2_frame_state_copy_regs (struct dwarf2_frame_state_reg_info *rs)
-{
- size_t size = rs->num_regs * sizeof (struct dwarf2_frame_state_reg_info);
- struct dwarf2_frame_state_reg *reg;
+ /* Base for DW_EH_PE_datarel encodings. */
+ bfd_vma dbase;
- reg = (struct dwarf2_frame_state_reg *) xmalloc (size);
- memcpy (reg, rs->reg, size);
+ /* Base for DW_EH_PE_textrel encodings. */
+ bfd_vma tbase;
+};
- return reg;
-}
+static struct dwarf2_fde *dwarf2_frame_find_fde (CORE_ADDR *pc,
+ CORE_ADDR *out_offset);
-/* Release the memory allocated to register set RS. */
+static int dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum,
+ int eh_frame_p);
-static void
-dwarf2_frame_state_free_regs (struct dwarf2_frame_state_reg_info *rs)
-{
- if (rs)
- {
- dwarf2_frame_state_free_regs (rs->prev);
+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
- xfree (rs->reg);
- xfree (rs);
- }
-}
+/* See dwarf2-frame.h. */
+bool dwarf2_frame_unwinders_enabled_p = true;
-/* Release the memory allocated to the frame state FS. */
+/* 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
-static void
-dwarf2_frame_state_free (void *p)
+dwarf2_frame_state::dwarf2_frame_state (CORE_ADDR pc_, struct dwarf2_cie *cie)
+ : pc (pc_), data_align (cie->data_alignment_factor),
+ code_align (cie->code_alignment_factor),
+ retaddr_column (cie->return_address_register)
{
- struct dwarf2_frame_state *fs = p;
-
- dwarf2_frame_state_free_regs (fs->initial.prev);
- dwarf2_frame_state_free_regs (fs->regs.prev);
- xfree (fs->initial.reg);
- xfree (fs->regs.reg);
- xfree (fs);
}
\f
/* Helper functions for execute_stack_op. */
static CORE_ADDR
-read_reg (void *baton, int reg)
+read_addr_from_reg (struct frame_info *this_frame, int reg)
{
- struct frame_info *next_frame = (struct frame_info *) baton;
- struct gdbarch *gdbarch = get_frame_arch (next_frame);
- int regnum;
- char *buf;
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ int regnum = dwarf_reg_to_regnum_or_error (gdbarch, reg);
- regnum = DWARF2_REG_TO_REGNUM (reg);
-
- buf = (char *) alloca (register_size (gdbarch, regnum));
- frame_unwind_register (next_frame, regnum, buf);
- return extract_typed_address (buf, builtin_type_void_data_ptr);
+ return address_from_register (regnum, this_frame);
}
+/* Execute the required actions for both the DW_CFA_restore and
+DW_CFA_restore_extended instructions. */
static void
-read_mem (void *baton, char *buf, CORE_ADDR addr, size_t len)
+dwarf2_restore_rule (struct gdbarch *gdbarch, ULONGEST reg_num,
+ struct dwarf2_frame_state *fs, int eh_frame_p)
{
- read_memory (addr, buf, len);
-}
+ ULONGEST reg;
-static void
-no_get_frame_base (void *baton, unsigned char **start, size_t *length)
-{
- internal_error (__FILE__, __LINE__,
- "Support for DW_OP_fbreg is unimplemented");
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg_num, eh_frame_p);
+ fs->regs.alloc_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.reg.size ())
+ 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)
+ {
+ int regnum = dwarf_reg_to_regnum (gdbarch, reg);
+
+ complaint (_("\
+incomplete CFI data; DW_CFA_restore unspecified\n\
+register %s (#%d) at %s"),
+ gdbarch_register_name (gdbarch, regnum), regnum,
+ paddress (gdbarch, fs->pc));
+ }
}
-static CORE_ADDR
-no_get_tls_address (void *baton, CORE_ADDR offset)
+class dwarf_expr_executor : public dwarf_expr_context
{
- internal_error (__FILE__, __LINE__,
- "Support for DW_OP_GNU_push_tls_address is unimplemented");
-}
+ public:
+
+ struct frame_info *this_frame;
+
+ CORE_ADDR read_addr_from_reg (int reg) override
+ {
+ return ::read_addr_from_reg (this_frame, reg);
+ }
+
+ struct value *get_reg_value (struct type *type, int reg) override
+ {
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ int regnum = dwarf_reg_to_regnum_or_error (gdbarch, reg);
+
+ return value_from_register (type, regnum, this_frame);
+ }
+
+ void read_mem (gdb_byte *buf, CORE_ADDR addr, size_t len) override
+ {
+ read_memory (addr, buf, len);
+ }
+
+ void get_frame_base (const gdb_byte **start, size_t *length) override
+ {
+ invalid ("DW_OP_fbreg");
+ }
+
+ void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind,
+ union call_site_parameter_u kind_u,
+ int deref_size) override
+ {
+ invalid ("DW_OP_entry_value");
+ }
+
+ CORE_ADDR get_object_address () override
+ {
+ invalid ("DW_OP_push_object_address");
+ }
+
+ CORE_ADDR get_frame_cfa () override
+ {
+ invalid ("DW_OP_call_frame_cfa");
+ }
+
+ CORE_ADDR get_tls_address (CORE_ADDR offset) override
+ {
+ invalid ("DW_OP_form_tls_address");
+ }
+
+ void dwarf_call (cu_offset die_offset) override
+ {
+ invalid ("DW_OP_call*");
+ }
+
+ struct value *dwarf_variable_value (sect_offset sect_off) override
+ {
+ invalid ("DW_OP_GNU_variable_value");
+ }
+
+ CORE_ADDR get_addr_index (unsigned int index) override
+ {
+ invalid ("DW_OP_addrx or DW_OP_GNU_addr_index");
+ }
+
+ private:
+
+ void invalid (const char *op) ATTRIBUTE_NORETURN
+ {
+ error (_("%s is invalid in this context"), op);
+ }
+};
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,
+ CORE_ADDR offset, struct frame_info *this_frame,
+ CORE_ADDR initial, int initial_in_stack_memory)
{
- struct dwarf_expr_context *ctx;
CORE_ADDR result;
- ctx = new_dwarf_expr_context ();
- ctx->baton = next_frame;
- ctx->read_reg = read_reg;
- ctx->read_mem = read_mem;
- ctx->get_frame_base = no_get_frame_base;
- ctx->get_tls_address = no_get_tls_address;
+ dwarf_expr_executor ctx;
+ scoped_value_mark free_values;
- dwarf_expr_push (ctx, initial);
- dwarf_expr_eval (ctx, exp, len);
- result = dwarf_expr_fetch (ctx, 0);
+ ctx.this_frame = this_frame;
+ ctx.gdbarch = get_frame_arch (this_frame);
+ ctx.addr_size = addr_size;
+ ctx.ref_addr_size = -1;
+ ctx.offset = offset;
- if (ctx->in_reg)
- result = read_reg (next_frame, result);
+ ctx.push_address (initial, initial_in_stack_memory);
+ ctx.eval (exp, len);
- free_dwarf_expr_context (ctx);
+ if (ctx.location == DWARF_VALUE_MEMORY)
+ result = ctx.fetch_address (0);
+ else if (ctx.location == DWARF_VALUE_REGISTER)
+ result = ctx.read_addr_from_reg (value_as_long (ctx.fetch (0)));
+ else
+ {
+ /* 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"));
+ }
return result;
}
\f
-static void
-execute_cfa_program (unsigned char *insn_ptr, unsigned char *insn_end,
- struct frame_info *next_frame,
- struct dwarf2_frame_state *fs)
+/* Execute FDE program from INSN_PTR possibly up to INSN_END or up to inferior
+ PC. Modify FS state accordingly. Return current INSN_PTR where the
+ execution has stopped, one can resume it on the next call. */
+
+static const gdb_byte *
+execute_cfa_program (struct dwarf2_fde *fde, const gdb_byte *insn_ptr,
+ const gdb_byte *insn_end, struct gdbarch *gdbarch,
+ CORE_ADDR pc, struct dwarf2_frame_state *fs)
{
- CORE_ADDR pc = frame_pc_unwind (next_frame);
- int bytes_read;
+ int eh_frame_p = fde->eh_frame_p;
+ unsigned int bytes_read;
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
while (insn_ptr < insn_end && fs->pc <= pc)
{
- unsigned char insn = *insn_ptr++;
- ULONGEST utmp, reg;
- LONGEST offset;
+ gdb_byte insn = *insn_ptr++;
+ uint64_t utmp, reg;
+ int64_t offset;
if ((insn & 0xc0) == DW_CFA_advance_loc)
fs->pc += (insn & 0x3f) * fs->code_align;
else if ((insn & 0xc0) == DW_CFA_offset)
{
reg = insn & 0x3f;
- insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp);
offset = utmp * fs->data_align;
- dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ fs->regs.alloc_regs (reg + 1);
fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET;
fs->regs.reg[reg].loc.offset = offset;
}
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->ptr_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, ®);
- insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp);
offset = utmp * fs->data_align;
- dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ fs->regs.alloc_regs (reg + 1);
fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET;
fs->regs.reg[reg].loc.offset = offset;
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];
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®);
+ dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p);
break;
case DW_CFA_undefined:
- insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
- dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
+ fs->regs.alloc_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, ®);
- dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
+ fs->regs.alloc_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, ®);
- insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
- dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp);
+ utmp = dwarf2_frame_adjust_regnum (gdbarch, utmp, eh_frame_p);
+ fs->regs.alloc_regs (reg + 1);
fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG;
fs->regs.reg[reg].loc.reg = utmp;
break;
{
struct dwarf2_frame_state_reg_info *new_rs;
- new_rs = XMALLOC (struct dwarf2_frame_state_reg_info);
- *new_rs = fs->regs;
- fs->regs.reg = dwarf2_frame_state_copy_regs (&fs->regs);
+ new_rs = new dwarf2_frame_state_reg_info (fs->regs);
fs->regs.prev = new_rs;
}
break;
if (old_rs == NULL)
{
- complaint (&symfile_complaints, "\
-bad CFI data; mismatched DW_CFA_restore_state at 0x%s", paddr (fs->pc));
+ complaint (_("\
+bad CFI data; mismatched DW_CFA_restore_state at %s"),
+ paddress (gdbarch, fs->pc));
}
else
- {
- xfree (fs->regs.reg);
- fs->regs = *old_rs;
- xfree (old_rs);
- }
+ fs->regs = std::move (*old_rs);
}
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, &utmp);
- fs->cfa_offset = utmp;
- fs->cfa_how = CFA_REG_OFFSET;
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®);
+ fs->regs.cfa_reg = reg;
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp);
+
+ 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 = safe_read_uleb128 (insn_ptr, insn_end, ®);
+ fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, 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 = safe_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 = safe_read_uleb128 (insn_ptr, insn_end, &utmp);
+ fs->regs.cfa_exp_len = utmp;
+ 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, ®);
- 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;
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
+ fs->regs.alloc_regs (reg + 1);
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp);
+ fs->regs.reg[reg].loc.exp.start = insn_ptr;
+ fs->regs.reg[reg].loc.exp.len = utmp;
fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_EXP;
insn_ptr += utmp;
break;
case DW_CFA_offset_extended_sf:
- insn_ptr = read_uleb128 (insn_ptr, insn_end, ®);
- insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset);
- offset += fs->data_align;
- dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
+ insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset);
+ offset *= fs->data_align;
+ fs->regs.alloc_regs (reg + 1);
fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET;
fs->regs.reg[reg].loc.offset = offset;
break;
+ case DW_CFA_val_offset:
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®);
+ fs->regs.alloc_regs (reg + 1);
+ insn_ptr = safe_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 = safe_read_uleb128 (insn_ptr, insn_end, ®);
+ fs->regs.alloc_regs (reg + 1);
+ insn_ptr = safe_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 = safe_read_uleb128 (insn_ptr, insn_end, ®);
+ fs->regs.alloc_regs (reg + 1);
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp);
+ fs->regs.reg[reg].loc.exp.start = insn_ptr;
+ fs->regs.reg[reg].loc.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_sleb128 (insn_ptr, insn_end, &offset);
- fs->cfa_offset = offset * fs->data_align;
- fs->cfa_how = CFA_REG_OFFSET;
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®);
+ fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, reg,
+ eh_frame_p);
+ insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &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;
+ insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset);
+ fs->regs.cfa_offset = offset * fs->data_align;
/* cfa_how deliberately not set. */
break;
case DW_CFA_GNU_args_size:
/* Ignored. */
- insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp);
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp);
+ break;
+
+ case DW_CFA_GNU_negative_offset_extended:
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®);
+ reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p);
+ insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp);
+ offset = utmp * fs->data_align;
+ fs->regs.alloc_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.");
+ if (insn >= DW_CFA_lo_user && insn <= DW_CFA_hi_user)
+ {
+ /* Handle vendor-specific CFI for different architectures. */
+ if (!gdbarch_execute_dwarf_cfa_vendor_op (gdbarch, insn, fs))
+ error (_("Call Frame Instruction op %d in vendor extension "
+ "space is not handled on this architecture."),
+ insn);
+ }
+ else
+ internal_error (__FILE__, __LINE__,
+ _("Unknown CFI encountered."));
}
}
}
- /* Don't allow remember/restore between CIE and FDE programs. */
- dwarf2_frame_state_free_regs (fs->regs.prev);
- fs->regs.prev = NULL;
+ if (fs->initial.reg.empty ())
+ {
+ /* Don't allow remember/restore between CIE and FDE programs. */
+ delete fs->regs.prev;
+ fs->regs.prev = NULL;
+ }
+
+ return insn_ptr;
}
+
+#if GDB_SELF_TEST
+
+namespace selftests {
+
+/* Unit test to function execute_cfa_program. */
+
+static void
+execute_cfa_program_test (struct gdbarch *gdbarch)
+{
+ struct dwarf2_fde fde;
+ struct dwarf2_cie cie;
+
+ memset (&fde, 0, sizeof fde);
+ memset (&cie, 0, sizeof cie);
+
+ cie.data_alignment_factor = -4;
+ cie.code_alignment_factor = 2;
+ fde.cie = &cie;
+
+ dwarf2_frame_state fs (0, fde.cie);
+
+ gdb_byte insns[] =
+ {
+ DW_CFA_def_cfa, 1, 4, /* DW_CFA_def_cfa: r1 ofs 4 */
+ DW_CFA_offset | 0x2, 1, /* DW_CFA_offset: r2 at cfa-4 */
+ DW_CFA_remember_state,
+ DW_CFA_restore_state,
+ };
+
+ const gdb_byte *insn_end = insns + sizeof (insns);
+ const gdb_byte *out = execute_cfa_program (&fde, insns, insn_end, gdbarch,
+ 0, &fs);
+
+ SELF_CHECK (out == insn_end);
+ SELF_CHECK (fs.pc == 0);
+
+ /* The instructions above only use r1 and r2, but the register numbers
+ used are adjusted by dwarf2_frame_adjust_regnum. */
+ auto r1 = dwarf2_frame_adjust_regnum (gdbarch, 1, fde.eh_frame_p);
+ auto r2 = dwarf2_frame_adjust_regnum (gdbarch, 2, fde.eh_frame_p);
+
+ SELF_CHECK (fs.regs.reg.size () == (std::max (r1, r2) + 1));
+
+ SELF_CHECK (fs.regs.reg[r2].how == DWARF2_FRAME_REG_SAVED_OFFSET);
+ SELF_CHECK (fs.regs.reg[r2].loc.offset == -4);
+
+ for (auto i = 0; i < fs.regs.reg.size (); i++)
+ if (i != r2)
+ SELF_CHECK (fs.regs.reg[i].how == DWARF2_FRAME_REG_UNSPECIFIED);
+
+ SELF_CHECK (fs.regs.cfa_reg == 1);
+ SELF_CHECK (fs.regs.cfa_offset == 4);
+ SELF_CHECK (fs.regs.cfa_how == CFA_REG_OFFSET);
+ SELF_CHECK (fs.regs.cfa_exp == NULL);
+ SELF_CHECK (fs.regs.prev == NULL);
+}
+
+} // namespace selftests
+#endif /* GDB_SELF_TEST */
+
\f
/* Architecture-specific operations. */
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 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);
+ struct dwarf2_frame_ops *ops
+ = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data);
ops->init_reg = init_reg;
}
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
+ = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data);
+
+ ops->init_reg (gdbarch, regnum, reg, this_frame);
+}
+
+/* Set the architecture-specific signal trampoline recognition
+ function for GDBARCH to SIGNAL_FRAME_P. */
+
+void
+dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch,
+ int (*signal_frame_p) (struct gdbarch *,
+ struct frame_info *))
{
- struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data);
+ struct dwarf2_frame_ops *ops
+ = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data);
- ops->init_reg (gdbarch, regnum, reg);
+ ops->signal_frame_p = signal_frame_p;
+}
+
+/* Query the architecture-specific signal frame recognizer for
+ THIS_FRAME. */
+
+static int
+dwarf2_frame_signal_frame_p (struct gdbarch *gdbarch,
+ struct frame_info *this_frame)
+{
+ struct dwarf2_frame_ops *ops
+ = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data);
+
+ if (ops->signal_frame_p == NULL)
+ return 0;
+ 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
+ = (struct dwarf2_frame_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
+ = (struct dwarf2_frame_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 compunit_symtab *cust;
+
+ cust = find_pc_compunit_symtab (fs->pc);
+ if (cust == NULL)
+ return;
+
+ if (producer_is_realview (COMPUNIT_PRODUCER (cust)))
+ {
+ 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
+ && (!startswith (fde->cie->augmentation, "armcc")
+ || strchr (fde->cie->augmentation + 5, '+') == NULL))
+ fs->armcc_cfa_offsets_reversed = 1;
+
+ return;
+ }
}
\f
+/* See dwarf2-frame.h. */
+
+int
+dwarf2_fetch_cfa_info (struct gdbarch *gdbarch, CORE_ADDR pc,
+ struct dwarf2_per_cu_data *data,
+ int *regnum_out, LONGEST *offset_out,
+ CORE_ADDR *text_offset_out,
+ const gdb_byte **cfa_start_out,
+ const gdb_byte **cfa_end_out)
+{
+ struct dwarf2_fde *fde;
+ CORE_ADDR text_offset;
+ CORE_ADDR pc1 = pc;
+
+ /* Find the correct FDE. */
+ fde = dwarf2_frame_find_fde (&pc1, &text_offset);
+ if (fde == NULL)
+ error (_("Could not compute CFA; needed to translate this expression"));
+
+ dwarf2_frame_state fs (pc1, fde->cie);
+
+ /* 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, fde->cie->initial_instructions,
+ fde->cie->end, gdbarch, pc, &fs);
+
+ /* Save the initialized register set. */
+ fs.initial = fs.regs;
+
+ /* Then decode the insns in the FDE up to our target PC. */
+ execute_cfa_program (fde, fde->instructions, fde->end, gdbarch, pc, &fs);
+
+ /* Calculate the CFA. */
+ switch (fs.regs.cfa_how)
+ {
+ case CFA_REG_OFFSET:
+ {
+ int regnum = dwarf_reg_to_regnum_or_error (gdbarch, fs.regs.cfa_reg);
+
+ *regnum_out = regnum;
+ if (fs.armcc_cfa_offsets_reversed)
+ *offset_out = -fs.regs.cfa_offset;
+ else
+ *offset_out = fs.regs.cfa_offset;
+ return 1;
+ }
+
+ case CFA_EXP:
+ *text_offset_out = text_offset;
+ *cfa_start_out = fs.regs.cfa_exp;
+ *cfa_end_out = fs.regs.cfa_exp + fs.regs.cfa_exp_len;
+ return 0;
+
+ default:
+ internal_error (__FILE__, __LINE__, _("Unknown CFA rule."));
+ }
+}
+
+\f
struct dwarf2_frame_cache
{
/* DWARF Call Frame Address. */
CORE_ADDR cfa;
+ /* Set if the return address column was marked as unavailable
+ (required non-collected memory or registers to compute). */
+ int unavailable_retaddr;
+
+ /* 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;
+
+ /* The .text offset. */
+ CORE_ADDR text_offset;
+
+ /* True if we already checked whether this frame is the bottom frame
+ of a virtual tail call frame chain. */
+ int checked_tailcall_bottom;
+
+ /* If not NULL then this frame is the bottom frame of a TAILCALL_FRAME
+ sequence. If NULL then it is a normal case with no TAILCALL_FRAME
+ involved. Non-bottom frames of a virtual tail call frames chain use
+ dwarf2_tailcall_frame_unwind unwinder so this field does not apply for
+ them. */
+ void *tailcall_cache;
+
+ /* The number of bytes to subtract from TAILCALL_FRAME frames frame
+ base to get the SP, to simulate the return address pushed on the
+ stack. */
+ LONGEST entry_cfa_sp_offset;
+ int entry_cfa_sp_offset_p;
};
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_cooked_regs (gdbarch);
struct dwarf2_frame_cache *cache;
- struct dwarf2_frame_state *fs;
struct dwarf2_fde *fde;
+ CORE_ADDR entry_pc;
+ const gdb_byte *instr;
if (*this_cache)
- return *this_cache;
+ return (struct dwarf2_frame_cache *) *this_cache;
/* Allocate a new cache. */
cache = FRAME_OBSTACK_ZALLOC (struct dwarf2_frame_cache);
cache->reg = FRAME_OBSTACK_CALLOC (num_regs, struct dwarf2_frame_state_reg);
-
- /* Allocate and initialize the frame state. */
- fs = XMALLOC (struct dwarf2_frame_state);
- memset (fs, 0, sizeof (struct dwarf2_frame_state));
- old_chain = make_cleanup (dwarf2_frame_state_free, fs);
+ *this_cache = cache;
/* 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);
+ CORE_ADDR pc1 = get_frame_address_in_block (this_frame);
/* Find the correct FDE. */
- fde = dwarf2_frame_find_fde (&fs->pc);
+ fde = dwarf2_frame_find_fde (&pc1, &cache->text_offset);
gdb_assert (fde != NULL);
- /* Extract any interesting information from the CIE. */
- fs->data_align = fde->cie->data_alignment_factor;
- fs->code_align = fde->cie->code_alignment_factor;
- fs->retaddr_column = fde->cie->return_address_register;
+ /* Allocate and initialize the frame state. */
+ struct dwarf2_frame_state fs (pc1, fde->cie);
+
+ 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, gdbarch,
+ get_frame_address_in_block (this_frame), &fs);
/* Save the initialized register set. */
- fs->initial = fs->regs;
- fs->initial.reg = dwarf2_frame_state_copy_regs (&fs->regs);
+ fs.initial = fs.regs;
+
+ /* Fetching the entry pc for THIS_FRAME won't necessarily result
+ in an address that's within the range of FDE locations. This
+ is due to the possibility of the function occupying non-contiguous
+ ranges. */
+ if (get_frame_func_if_available (this_frame, &entry_pc)
+ && fde->initial_location <= entry_pc
+ && entry_pc < fde->initial_location + fde->address_range)
+ {
+ /* Decode the insns in the FDE up to the entry PC. */
+ instr = execute_cfa_program (fde, fde->instructions, fde->end, gdbarch,
+ entry_pc, &fs);
+
+ if (fs.regs.cfa_how == CFA_REG_OFFSET
+ && (dwarf_reg_to_regnum (gdbarch, fs.regs.cfa_reg)
+ == gdbarch_sp_regnum (gdbarch)))
+ {
+ cache->entry_cfa_sp_offset = fs.regs.cfa_offset;
+ cache->entry_cfa_sp_offset_p = 1;
+ }
+ }
+ else
+ instr = fde->instructions;
/* 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, instr, fde->end, gdbarch,
+ get_frame_address_in_block (this_frame), &fs);
- /* Caclulate the CFA. */
- switch (fs->cfa_how)
+ try
{
- case CFA_REG_OFFSET:
- cache->cfa = read_reg (next_frame, fs->cfa_reg);
- cache->cfa += fs->cfa_offset;
- break;
-
- case CFA_EXP:
- cache->cfa =
- execute_stack_op (fs->cfa_exp, fs->cfa_exp_len, next_frame, 0);
- break;
+ /* Calculate the CFA. */
+ switch (fs.regs.cfa_how)
+ {
+ case CFA_REG_OFFSET:
+ cache->cfa = read_addr_from_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.regs.cfa_exp, fs.regs.cfa_exp_len,
+ cache->addr_size, cache->text_offset,
+ this_frame, 0, 0);
+ break;
+
+ default:
+ internal_error (__FILE__, __LINE__, _("Unknown CFA rule."));
+ }
+ }
+ catch (const gdb_exception_error &ex)
+ {
+ if (ex.error == NOT_AVAILABLE_ERROR)
+ {
+ cache->unavailable_retaddr = 1;
+ return cache;
+ }
- default:
- internal_error (__FILE__, __LINE__, "Unknown CFA rule.");
+ throw;
}
/* Initialize the register state. */
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
location information in the cache. Note that we don't skip the
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). */
+ correspond to a real register. */
{
int column; /* CFI speak for "register number". */
- for (column = 0; column < fs->regs.num_regs; column++)
+ for (column = 0; column < fs.regs.reg.size (); column++)
{
/* Use the GDB register number as the destination index. */
- int regnum = DWARF2_REG_TO_REGNUM (column);
+ int regnum = dwarf_reg_to_regnum (gdbarch, column);
- /* If there's no corresponding GDB register, ignore it. */
+ /* Protect against a target returning a bad register. */
if (regnum < 0 || regnum >= num_regs)
continue;
problems when a debug info register falls outside of the
table. We need a way of iterating through all the valid
DWARF2 register numbers. */
- if (fs->regs.reg[column].how == DWARF2_FRAME_REG_UNSPECIFIED)
- complaint (&symfile_complaints,
- "Incomplete CFI data; unspecified registers at 0x%s",
- paddr (fs->pc));
+ if (fs.regs.reg[column].how == DWARF2_FRAME_REG_UNSPECIFIED)
+ {
+ if (cache->reg[regnum].how == DWARF2_FRAME_REG_UNSPECIFIED)
+ complaint (_("\
+incomplete CFI data; unspecified registers (e.g., %s) at %s"),
+ gdbarch_register_name (gdbarch, regnum),
+ paddress (gdbarch, fs.pc));
+ }
else
- cache->reg[regnum] = fs->regs.reg[column];
+ cache->reg[regnum] = fs.regs.reg[column];
}
}
- /* Eliminate any DWARF2_FRAME_REG_RA rules. */
+ /* Eliminate any DWARF2_FRAME_REG_RA rules, and save the information
+ we need for evaluating DWARF2_FRAME_REG_RA_OFFSET rules. */
{
int regnum;
for (regnum = 0; regnum < num_regs; regnum++)
{
- if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA)
+ if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA
+ || cache->reg[regnum].how == DWARF2_FRAME_REG_RA_OFFSET)
{
- struct dwarf2_frame_state_reg *retaddr_reg =
- &fs->regs.reg[fs->retaddr_column];
+ const std::vector<struct dwarf2_frame_state_reg> ®s
+ = fs.regs.reg;
+ ULONGEST retaddr_column = fs.retaddr_column;
/* It seems rather bizarre to specify an "empty" column as
the return adress column. However, this is exactly
what GCC does on some targets. It turns out that GCC
assumes that the return address can be found in the
register corresponding to the return address column.
- Incidentally, that's how should treat a return address
- column specifying "same value" too. */
- if (fs->retaddr_column < fs->regs.num_regs
- && retaddr_reg->how != DWARF2_FRAME_REG_UNSPECIFIED
- && retaddr_reg->how != DWARF2_FRAME_REG_SAME_VALUE)
- cache->reg[regnum] = *retaddr_reg;
+ Incidentally, that's how we should treat a return
+ address column specifying "same value" too. */
+ if (fs.retaddr_column < fs.regs.reg.size ()
+ && regs[retaddr_column].how != DWARF2_FRAME_REG_UNSPECIFIED
+ && regs[retaddr_column].how != DWARF2_FRAME_REG_SAME_VALUE)
+ {
+ if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA)
+ cache->reg[regnum] = regs[retaddr_column];
+ else
+ cache->retaddr_reg = regs[retaddr_column];
+ }
else
{
- cache->reg[regnum].loc.reg = fs->retaddr_column;
- cache->reg[regnum].how = DWARF2_FRAME_REG_SAVED_REG;
+ if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA)
+ {
+ cache->reg[regnum].loc.reg = fs.retaddr_column;
+ cache->reg[regnum].how = DWARF2_FRAME_REG_SAVED_REG;
+ }
+ else
+ {
+ cache->retaddr_reg.loc.reg = fs.retaddr_column;
+ cache->retaddr_reg.how = DWARF2_FRAME_REG_SAVED_REG;
+ }
}
}
}
}
- do_cleanups (old_chain);
+ if (fs.retaddr_column < fs.regs.reg.size ()
+ && fs.regs.reg[fs.retaddr_column].how == DWARF2_FRAME_REG_UNDEFINED)
+ cache->undefined_retaddr = 1;
- *this_cache = cache;
return cache;
}
+static enum unwind_stop_reason
+dwarf2_frame_unwind_stop_reason (struct frame_info *this_frame,
+ void **this_cache)
+{
+ struct dwarf2_frame_cache *cache
+ = dwarf2_frame_cache (this_frame, this_cache);
+
+ if (cache->unavailable_retaddr)
+ return UNWIND_UNAVAILABLE;
+
+ if (cache->undefined_retaddr)
+ return UNWIND_OUTERMOST;
+
+ return UNWIND_NO_REASON;
+}
+
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);
- (*this_id) = frame_id_build (cache->cfa, frame_func_unwind (next_frame));
+ if (cache->unavailable_retaddr)
+ (*this_id) = frame_id_build_unavailable_stack (get_frame_func (this_frame));
+ else if (cache->undefined_retaddr)
+ return;
+ else
+ (*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;
+
+ /* Check whether THIS_FRAME is the bottom frame of a virtual tail
+ call frame chain. */
+ if (!cache->checked_tailcall_bottom)
+ {
+ cache->checked_tailcall_bottom = 1;
+ dwarf2_tailcall_sniffer_first (this_frame, &cache->tailcall_cache,
+ (cache->entry_cfa_sp_offset_p
+ ? &cache->entry_cfa_sp_offset : NULL));
+ }
+
+ /* Non-bottom frames of a virtual tail call frames chain use
+ dwarf2_tailcall_frame_unwind unwinder so this code does not apply for
+ them. If dwarf2_tailcall_prev_register_first does not have specific value
+ unwind the register, tail call frames are assumed to have the register set
+ of the top caller. */
+ if (cache->tailcall_cache)
+ {
+ struct value *val;
+
+ val = dwarf2_tailcall_prev_register_first (this_frame,
+ &cache->tailcall_cache,
+ regnum);
+ if (val)
+ return val;
+ }
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:
- regnum = DWARF2_REG_TO_REGNUM (cache->reg[regnum].loc.reg);
- frame_register_unwind (next_frame, regnum,
- optimizedp, lvalp, addrp, realnump, valuep);
- break;
+ realnum = dwarf_reg_to_regnum_or_error
+ (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.start,
+ cache->reg[regnum].loc.exp.len,
+ cache->addr_size, cache->text_offset,
+ 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.start,
+ cache->reg[regnum].loc.exp.len,
+ cache->addr_size, cache->text_offset,
+ 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. */
- frame_register_unwind (next_frame, regnum,
- optimizedp, lvalp, addrp, realnump, valuep);
- break;
+ return frame_unwind_got_register (this_frame, regnum, regnum);
case DWARF2_FRAME_REG_SAME_VALUE:
- frame_register_unwind (next_frame, regnum,
- optimizedp, lvalp, addrp, 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:
+ addr = cache->reg[regnum].loc.offset;
+ regnum = dwarf_reg_to_regnum_or_error
+ (gdbarch, cache->retaddr_reg.loc.reg);
+ addr += get_frame_register_unsigned (this_frame, regnum);
+ return frame_unwind_got_address (this_frame, regnum, addr);
+
+ case DWARF2_FRAME_REG_FN:
+ return cache->reg[regnum].loc.fn (this_frame, this_cache, regnum);
default:
- internal_error (__FILE__, __LINE__, "Unknown register rule.");
+ internal_error (__FILE__, __LINE__, _("Unknown register rule."));
}
}
+/* Proxy for tailcall_frame_dealloc_cache for bottom frame of a virtual tail
+ call frames chain. */
+
+static void
+dwarf2_frame_dealloc_cache (struct frame_info *self, void *this_cache)
+{
+ struct dwarf2_frame_cache *cache = dwarf2_frame_cache (self, &this_cache);
+
+ if (cache->tailcall_cache)
+ dwarf2_tailcall_frame_unwind.dealloc_cache (self, cache->tailcall_cache);
+}
+
+static int
+dwarf2_frame_sniffer (const struct frame_unwind *self,
+ struct frame_info *this_frame, void **this_cache)
+{
+ if (!dwarf2_frame_unwinders_enabled_p)
+ return 0;
+
+ /* Grab an address that is guaranteed 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, NULL);
+
+ 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;
+
+ if (self->type != NORMAL_FRAME)
+ return 0;
+
+ return 1;
+}
+
static const struct frame_unwind dwarf2_frame_unwind =
{
NORMAL_FRAME,
+ dwarf2_frame_unwind_stop_reason,
dwarf2_frame_this_id,
- dwarf2_frame_prev_register
+ dwarf2_frame_prev_register,
+ NULL,
+ dwarf2_frame_sniffer,
+ dwarf2_frame_dealloc_cache
};
-const struct frame_unwind *
-dwarf2_frame_sniffer (struct frame_info *next_frame)
+static const struct frame_unwind dwarf2_signal_frame_unwind =
{
- /* 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 &dwarf2_frame_unwind;
+ SIGTRAMP_FRAME,
+ dwarf2_frame_unwind_stop_reason,
+ dwarf2_frame_this_id,
+ dwarf2_frame_prev_register,
+ NULL,
+ dwarf2_frame_sniffer,
- return NULL;
+ /* TAILCALL_CACHE can never be in such frame to need dealloc_cache. */
+ NULL
+};
+
+/* Append the DWARF-2 frame unwinders to GDBARCH's list. */
+
+void
+dwarf2_append_unwinders (struct gdbarch *gdbarch)
+{
+ /* TAILCALL_FRAME must be first to find the record by
+ dwarf2_tailcall_sniffer_first. */
+ frame_unwind_append_unwinder (gdbarch, &dwarf2_tailcall_frame_unwind);
+
+ 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, NULL))
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;
- /* Address size for this unit - from unit header. */
- unsigned char addr_size;
+/* 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. */
- /* 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;
-};
-
-const struct objfile_data *dwarf2_frame_objfile_data;
-
-static unsigned int
-read_1_byte (bfd *bfd, char *buf)
+CORE_ADDR
+dwarf2_frame_cfa (struct frame_info *this_frame)
{
- return bfd_get_8 (abfd, (bfd_byte *) buf);
+ if (frame_unwinder_is (this_frame, &record_btrace_tailcall_frame_unwind)
+ || frame_unwinder_is (this_frame, &record_btrace_frame_unwind))
+ throw_error (NOT_AVAILABLE_ERROR,
+ _("cfa not available for record btrace target"));
+
+ while (get_frame_type (this_frame) == INLINE_FRAME)
+ this_frame = get_prev_frame (this_frame);
+ if (get_frame_unwind_stop_reason (this_frame) == UNWIND_UNAVAILABLE)
+ throw_error (NOT_AVAILABLE_ERROR,
+ _("can't compute CFA for this frame: "
+ "required registers or memory are unavailable"));
+
+ if (get_frame_id (this_frame).stack_status != FID_STACK_VALID)
+ throw_error (NOT_AVAILABLE_ERROR,
+ _("can't compute CFA for this frame: "
+ "frame base not available"));
+
+ return get_frame_base (this_frame);
}
+\f
+const struct objfile_key<dwarf2_fde_table,
+ gdb::noop_deleter<dwarf2_fde_table>>
+ dwarf2_frame_objfile_data;
static unsigned int
-read_4_bytes (bfd *abfd, char *buf)
+read_1_byte (bfd *abfd, const gdb_byte *buf)
{
- return bfd_get_32 (abfd, (bfd_byte *) buf);
+ return bfd_get_8 (abfd, buf);
}
-static ULONGEST
-read_8_bytes (bfd *abfd, char *buf)
+static unsigned int
+read_4_bytes (bfd *abfd, const gdb_byte *buf)
{
- return bfd_get_64 (abfd, (bfd_byte *) buf);
+ return bfd_get_32 (abfd, buf);
}
static ULONGEST
-read_unsigned_leb128 (bfd *abfd, char *buf, unsigned int *bytes_read_ptr)
+read_8_bytes (bfd *abfd, const gdb_byte *buf)
{
- ULONGEST result;
- unsigned int num_read;
- int shift;
- unsigned char byte;
-
- result = 0;
- shift = 0;
- num_read = 0;
-
- do
- {
- byte = bfd_get_8 (abfd, (bfd_byte *) buf);
- buf++;
- num_read++;
- result |= ((byte & 0x7f) << shift);
- shift += 7;
- }
- while (byte & 0x80);
-
- *bytes_read_ptr = num_read;
-
- return result;
-}
-
-static LONGEST
-read_signed_leb128 (bfd *abfd, char *buf, unsigned int *bytes_read_ptr)
-{
- LONGEST result;
- int shift;
- unsigned int num_read;
- unsigned char byte;
-
- result = 0;
- shift = 0;
- num_read = 0;
-
- do
- {
- byte = bfd_get_8 (abfd, (bfd_byte *) buf);
- buf++;
- num_read++;
- result |= ((byte & 0x7f) << shift);
- shift += 7;
- }
- while (byte & 0x80);
-
- if ((shift < 32) && (byte & 0x40))
- result |= -(1 << shift);
-
- *bytes_read_ptr = num_read;
-
- return result;
+ return bfd_get_64 (abfd, buf);
}
static ULONGEST
-read_initial_length (bfd *abfd, char *buf, unsigned int *bytes_read_ptr)
+read_initial_length (bfd *abfd, const gdb_byte *buf,
+ unsigned int *bytes_read_ptr)
{
- LONGEST result;
+ ULONGEST 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)
case 8:
return DW_EH_PE_udata8;
default:
- internal_error (__FILE__, __LINE__, "Unsupported address 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");
+ internal_error (__FILE__, __LINE__, _("Unsupported address size"));
}
}
static CORE_ADDR
-read_encoded_value (struct comp_unit *unit, unsigned char encoding,
- 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;
FDE's. */
if (encoding & DW_EH_PE_indirect)
internal_error (__FILE__, __LINE__,
- "Unsupported encoding: DW_EH_PE_indirect");
+ _("Unsupported encoding: DW_EH_PE_indirect"));
*bytes_read_ptr = 0;
base = 0;
break;
case DW_EH_PE_pcrel:
- base = bfd_get_section_vma (unit->bfd, unit->dwarf_frame_section);
+ base = bfd_section_vma (unit->dwarf_frame_section);
base += (buf - unit->dwarf_frame_buffer);
break;
case DW_EH_PE_datarel:
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;
}
break;
default:
- internal_error (__FILE__, __LINE__, "Invalid or unsupported encoding");
+ internal_error (__FILE__, __LINE__,
+ _("Invalid or unsupported encoding"));
}
- if ((encoding & 0x0f) == 0x00)
- encoding |= encoding_for_size (ptr_len);
+ if ((encoding & 0x07) == 0x00)
+ {
+ 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:
+ {
+ uint64_t value;
+ const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7;
+
+ *bytes_read_ptr += safe_read_uleb128 (buf, end_buf, &value) - buf;
+ return base + value;
+ }
case DW_EH_PE_udata2:
*bytes_read_ptr += 2;
return (base + bfd_get_16 (unit->abfd, (bfd_byte *) buf));
case DW_EH_PE_udata8:
*bytes_read_ptr += 8;
return (base + bfd_get_64 (unit->abfd, (bfd_byte *) buf));
+ case DW_EH_PE_sleb128:
+ {
+ int64_t value;
+ const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7;
+
+ *bytes_read_ptr += safe_read_sleb128 (buf, end_buf, &value) - buf;
+ return base + value;
+ }
case DW_EH_PE_sdata2:
*bytes_read_ptr += 2;
return (base + bfd_get_signed_16 (unit->abfd, (bfd_byte *) buf));
*bytes_read_ptr += 8;
return (base + bfd_get_signed_64 (unit->abfd, (bfd_byte *) buf));
default:
- internal_error (__FILE__, __LINE__, "Invalid or unsupported encoding");
+ internal_error (__FILE__, __LINE__,
+ _("Invalid or unsupported encoding"));
}
}
\f
-/* GCC uses a single CIE for all FDEs in a .debug_frame section.
- That's why we use a simple linked list here. */
-
+/* 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 (const dwarf2_cie_table &cie_table, ULONGEST cie_pointer)
{
- struct dwarf2_cie *cie = unit->cie;
-
- while (cie)
- {
- if (cie->cie_pointer == cie_pointer)
- return cie;
-
- cie = cie->next;
- }
-
+ auto iter = cie_table.find (cie_pointer);
+ if (iter != cie_table.end ())
+ return iter->second;
return NULL;
}
-static void
-add_cie (struct comp_unit *unit, struct dwarf2_cie *cie)
+static inline int
+bsearch_fde_cmp (const dwarf2_fde *fde, CORE_ADDR seek_pc)
{
- cie->next = unit->cie;
- unit->cie = cie;
+ if (fde->initial_location + fde->address_range <= seek_pc)
+ return -1;
+ if (fde->initial_location <= seek_pc)
+ return 0;
+ return 1;
}
/* Find the FDE for *PC. Return a pointer to the FDE, and store the
- inital location associated with it into *PC. */
+ initial location associated with it into *PC. */
static struct dwarf2_fde *
-dwarf2_frame_find_fde (CORE_ADDR *pc)
+dwarf2_frame_find_fde (CORE_ADDR *pc, CORE_ADDR *out_offset)
{
- struct objfile *objfile;
-
- ALL_OBJFILES (objfile)
+ for (objfile *objfile : current_program_space->objfiles ())
{
- struct dwarf2_fde *fde;
+ struct dwarf2_fde_table *fde_table;
CORE_ADDR offset;
+ CORE_ADDR seek_pc;
- fde = objfile_data (objfile, dwarf2_frame_objfile_data);
- if (fde == NULL)
+ fde_table = dwarf2_frame_objfile_data.get (objfile);
+ if (fde_table == NULL)
+ {
+ dwarf2_build_frame_info (objfile);
+ fde_table = dwarf2_frame_objfile_data.get (objfile);
+ }
+ 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;
- }
-
- fde = fde->next;
- }
+ gdb_assert (fde_table->num_entries > 0);
+ if (*pc < offset + fde_table->entries[0]->initial_location)
+ continue;
+
+ seek_pc = *pc - offset;
+ auto end = fde_table->entries + fde_table->num_entries;
+ auto it = gdb::binary_search (fde_table->entries, end, seek_pc, bsearch_fde_cmp);
+ if (it != end)
+ {
+ *pc = (*it)->initial_location + offset;
+ if (out_offset)
+ *out_offset = offset;
+ return *it;
+ }
}
-
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 = XRESIZEVEC (struct dwarf2_fde *, fde_table->entries,
+ fde_table->num_entries);
+ fde_table->entries[fde_table->num_entries - 1] = fde;
}
-#ifdef CC_HAS_LONG_LONG
#define DW64_CIE_ID 0xffffffffffffffffULL
-#else
-#define DW64_CIE_ID ~0
-#endif
-static char *decode_frame_entry (struct comp_unit *unit, char *start,
- int eh_frame_p);
+/* Defines the type of eh_frames that are expected to be decoded: CIE, FDE
+ or any of them. */
+
+enum eh_frame_type
+{
+ EH_CIE_TYPE_ID = 1 << 0,
+ EH_FDE_TYPE_ID = 1 << 1,
+ EH_CIE_OR_FDE_TYPE_ID = EH_CIE_TYPE_ID | EH_FDE_TYPE_ID
+};
-/* 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 const gdb_byte *decode_frame_entry (struct comp_unit *unit,
+ const gdb_byte *start,
+ int eh_frame_p,
+ dwarf2_cie_table &cie_table,
+ struct dwarf2_fde_table *fde_table,
+ enum eh_frame_type entry_type);
+
+/* Decode the next CIE or FDE, entry_type specifies the expected type.
+ Return NULL if invalid input, otherwise the next byte to be processed. */
+
+static const gdb_byte *
+decode_frame_entry_1 (struct comp_unit *unit, const gdb_byte *start,
+ int eh_frame_p,
+ dwarf2_cie_table &cie_table,
+ struct dwarf2_fde_table *fde_table,
+ enum eh_frame_type entry_type)
{
- char *buf;
- LONGEST length;
+ struct gdbarch *gdbarch = get_objfile_arch (unit->objfile);
+ const gdb_byte *buf, *end;
+ ULONGEST length;
unsigned int bytes_read;
int dwarf64_p;
ULONGEST cie_id;
ULONGEST cie_pointer;
- char *end;
+ int64_t sleb128;
+ uint64_t uleb128;
buf = start;
length = read_initial_length (unit->abfd, buf, &bytes_read);
buf += bytes_read;
- end = buf + length;
-
- /* Are we still within the section? */
- if (end > unit->dwarf_frame_buffer + unit->dwarf_frame_size)
- return NULL;
+ end = buf + (size_t) length;
if (length == 0)
return end;
+ /* Are we still within the section? */
+ if (end <= buf || end > unit->dwarf_frame_buffer + unit->dwarf_frame_size)
+ return NULL;
+
/* Distinguish between 32 and 64-bit encoded frame info. */
dwarf64_p = (bytes_read == 12);
char *augmentation;
unsigned int cie_version;
+ /* Check that a CIE was expected. */
+ if ((entry_type & EH_CIE_TYPE_ID) == 0)
+ error (_("Found a CIE when not expecting it."));
+
/* Record the offset into the .debug_frame section of this CIE. */
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 *)
- obstack_alloc (&unit->objfile->objfile_obstack,
- sizeof (struct dwarf2_cie));
+ cie = XOBNEW (&unit->objfile->objfile_obstack, struct dwarf2_cie);
cie->initial_instructions = NULL;
cie->cie_pointer = cie_pointer;
/* The encoding for FDE's in a normal .debug_frame section
- depends on the target address size as specified in the
- Compilation Unit Header. */
- cie->encoding = encoding_for_size (unit->addr_size);
+ depends on the target address size. */
+ cie->encoding = DW_EH_PE_absptr;
+
+ /* 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 (startswith (augmentation, "armcc"))
+ 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;
}
- cie->code_alignment_factor =
- read_unsigned_leb128 (unit->abfd, buf, &bytes_read);
- buf += bytes_read;
+ 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_dwarf2_addr_size (gdbarch);
+ cie->segment_size = 0;
+ }
+ /* Address values in .eh_frame sections are defined to have the
+ target's pointer size. Watchout: This breaks frame info for
+ targets with pointer size < address size, unless a .debug_frame
+ section exists as well. */
+ if (eh_frame_p)
+ cie->ptr_size = gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT;
+ else
+ cie->ptr_size = cie->addr_size;
- cie->data_alignment_factor =
- read_signed_leb128 (unit->abfd, buf, &bytes_read);
- buf += bytes_read;
+ buf = gdb_read_uleb128 (buf, end, &uleb128);
+ if (buf == NULL)
+ return NULL;
+ cie->code_alignment_factor = uleb128;
+
+ buf = gdb_read_sleb128 (buf, end, &sleb128);
+ if (buf == NULL)
+ return NULL;
+ cie->data_alignment_factor = sleb128;
if (cie_version == 1)
{
cie->return_address_register = read_1_byte (unit->abfd, buf);
- bytes_read = 1;
+ ++buf;
}
else
- cie->return_address_register = read_unsigned_leb128 (unit->abfd, buf,
- &bytes_read);
- buf += bytes_read;
+ {
+ buf = gdb_read_uleb128 (buf, end, &uleb128);
+ if (buf == NULL)
+ return NULL;
+ cie->return_address_register = uleb128;
+ }
+
+ cie->return_address_register
+ = dwarf2_frame_adjust_regnum (gdbarch,
+ cie->return_address_register,
+ eh_frame_p);
cie->saw_z_augmentation = (*augmentation == 'z');
if (cie->saw_z_augmentation)
{
- ULONGEST length;
+ uint64_t uleb_length;
- length = read_unsigned_leb128 (unit->abfd, buf, &bytes_read);
- buf += bytes_read;
- if (buf > end)
+ buf = gdb_read_uleb128 (buf, end, &uleb_length);
+ if (buf == NULL)
return NULL;
- cie->initial_instructions = buf + length;
+ cie->initial_instructions = buf + uleb_length;
augmentation++;
}
/* "P" indicates a personality routine in the CIE augmentation. */
else if (*augmentation == 'P')
{
- /* Skip. */
- buf += size_of_encoded_value (*buf++);
+ /* Skip. Avoid indirection since we throw away the result. */
+ gdb_byte encoding = (*buf++) & ~DW_EH_PE_indirect;
+ read_encoded_value (unit, encoding, cie->ptr_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);
+ cie_table[cie->cie_pointer] = cie;
}
else
{
/* This is a FDE. */
struct dwarf2_fde *fde;
+ CORE_ADDR addr;
+
+ /* Check that an FDE was expected. */
+ if ((entry_type & EH_FDE_TYPE_ID) == 0)
+ error (_("Found an FDE when not expecting it."));
/* In an .eh_frame section, the CIE pointer is the delta between the
address within the FDE where the CIE pointer is stored and the
if (cie_pointer >= unit->dwarf_frame_size)
return NULL;
- fde = (struct dwarf2_fde *)
- obstack_alloc (&unit->objfile->objfile_obstack,
- sizeof (struct dwarf2_fde));
- fde->cie = find_cie (unit, cie_pointer);
+ fde = XOBNEW (&unit->objfile->objfile_obstack, struct dwarf2_fde);
+ 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,
+ EH_CIE_TYPE_ID);
+ 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);
+ addr = read_encoded_value (unit, fde->cie->encoding, fde->cie->ptr_size,
+ buf, &bytes_read, 0);
+ fde->initial_location = gdbarch_adjust_dwarf2_addr (gdbarch, addr);
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->ptr_size, buf, &bytes_read, 0);
+ addr = gdbarch_adjust_dwarf2_addr (gdbarch, addr + fde->address_range);
+ fde->address_range = addr - fde->initial_location;
buf += bytes_read;
/* A 'z' augmentation in the CIE implies the presence of an
can skip the whole thing. */
if (fde->cie->saw_z_augmentation)
{
- ULONGEST length;
+ uint64_t uleb_length;
- length = read_unsigned_leb128 (unit->abfd, buf, &bytes_read);
- buf += bytes_read + length;
+ buf = gdb_read_uleb128 (buf, end, &uleb_length);
+ if (buf == NULL)
+ return NULL;
+ buf += uleb_length;
if (buf > end)
return NULL;
}
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)
+/* Read a CIE or FDE in BUF and decode it. Entry_type specifies whether we
+ expect an FDE or a CIE. */
+
+static const gdb_byte *
+decode_frame_entry (struct comp_unit *unit, const gdb_byte *start,
+ int eh_frame_p,
+ dwarf2_cie_table &cie_table,
+ struct dwarf2_fde_table *fde_table,
+ enum eh_frame_type entry_type)
{
enum { NONE, ALIGN4, ALIGN8, FAIL } workaround = NONE;
- char *ret;
- const char *msg;
+ const 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, entry_type);
if (ret != NULL)
break;
break;
case ALIGN4:
- complaint (&symfile_complaints,
- "Corrupt data in %s:%s; align 4 workaround apparently succeeded",
+ complaint (_("\
+Corrupt data in %s:%s; align 4 workaround apparently succeeded"),
unit->dwarf_frame_section->owner->filename,
unit->dwarf_frame_section->name);
break;
case ALIGN8:
- complaint (&symfile_complaints,
- "Corrupt data in %s:%s; align 8 workaround apparently succeeded",
+ complaint (_("\
+Corrupt data in %s:%s; align 8 workaround apparently succeeded"),
unit->dwarf_frame_section->owner->filename,
unit->dwarf_frame_section->name);
break;
default:
- complaint (&symfile_complaints,
- "Corrupt data in %s:%s",
+ complaint (_("Corrupt data in %s:%s"),
unit->dwarf_frame_section->owner->filename,
unit->dwarf_frame_section->name);
break;
return ret;
}
\f
+static bool
+fde_is_less_than (const dwarf2_fde *aa, const dwarf2_fde *bb)
+{
+ 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 aa < bb;
+ else
+ /* Put eh_frame entries after debug_frame ones. */
+ return aa->eh_frame_p < bb->eh_frame_p;
+ }
-/* 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;
-
-/* Imported from dwarf2read.c. */
-extern char *dwarf2_read_section (struct objfile *objfile, asection *sectp);
+ return aa->initial_location < bb->initial_location;
+}
void
dwarf2_build_frame_info (struct objfile *objfile)
{
- struct comp_unit unit;
- char *frame_ptr;
+ struct comp_unit *unit;
+ const gdb_byte *frame_ptr;
+ dwarf2_cie_table cie_table;
+ struct dwarf2_fde_table fde_table;
+ struct dwarf2_fde_table *fde_table2;
+
+ 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.addr_size = objfile->obfd->arch_info->bits_per_address / 8;
- 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 = XOBNEW (&objfile->objfile_obstack, comp_unit);
+ unit->abfd = objfile->obfd;
+ unit->objfile = objfile;
+ unit->dbase = 0;
+ unit->tbase = 0;
+
+ if (objfile->separate_debug_objfile_backlink == NULL)
{
- 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");
- if (got)
- 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");
- if (txt)
- 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);
+ /* Do not read .eh_frame from separate file as they must be also
+ present in the main file. */
+ dwarf2_get_section_info (objfile, DWARF2_EH_FRAME,
+ &unit->dwarf_frame_section,
+ &unit->dwarf_frame_buffer,
+ &unit->dwarf_frame_size);
+ if (unit->dwarf_frame_size)
+ {
+ asection *got, *txt;
+
+ /* 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");
+ if (got)
+ 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");
+ if (txt)
+ unit->tbase = txt->vma;
+
+ try
+ {
+ 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,
+ EH_CIE_OR_FDE_TYPE_ID);
+ }
+
+ catch (const gdb_exception_error &e)
+ {
+ warning (_("skipping .eh_frame info of %s: %s"),
+ objfile_name (objfile), e.what ());
+
+ if (fde_table.num_entries != 0)
+ {
+ xfree (fde_table.entries);
+ fde_table.entries = NULL;
+ fde_table.num_entries = 0;
+ }
+ /* The cie_table is discarded below. */
+ }
+
+ cie_table.clear ();
+ }
}
- if (dwarf_frame_section)
+ dwarf2_get_section_info (objfile, DWARF2_DEBUG_FRAME,
+ &unit->dwarf_frame_section,
+ &unit->dwarf_frame_buffer,
+ &unit->dwarf_frame_size);
+ if (unit->dwarf_frame_size)
{
- 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);
+ int num_old_fde_entries = fde_table.num_entries;
+
+ try
+ {
+ 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,
+ EH_CIE_OR_FDE_TYPE_ID);
+ }
+ catch (const gdb_exception_error &e)
+ {
+ warning (_("skipping .debug_frame info of %s: %s"),
+ objfile_name (objfile), e.what ());
+
+ if (fde_table.num_entries != 0)
+ {
+ fde_table.num_entries = num_old_fde_entries;
+ if (num_old_fde_entries == 0)
+ {
+ xfree (fde_table.entries);
+ fde_table.entries = NULL;
+ }
+ else
+ {
+ fde_table.entries
+ = XRESIZEVEC (struct dwarf2_fde *, fde_table.entries,
+ fde_table.num_entries);
+ }
+ }
+ fde_table.num_entries = num_old_fde_entries;
+ }
+ }
+
+ /* Copy fde_table to obstack: it is needed at runtime. */
+ fde_table2 = XOBNEW (&objfile->objfile_obstack, struct dwarf2_fde_table);
+
+ if (fde_table.num_entries == 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. */
+ std::sort (fde_table.entries, fde_table.entries + fde_table.num_entries,
+ fde_is_less_than);
+
+ /* 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
+ = (struct dwarf2_fde **) obstack_finish (&objfile->objfile_obstack);
+
+ /* Discard the original fde_table. */
+ xfree (fde_table.entries);
}
+
+ dwarf2_frame_objfile_data.set (objfile, fde_table2);
}
-/* Provide a prototype to silence -Wmissing-prototypes. */
-void _initialize_dwarf2_frame (void);
+/* Handle 'maintenance show dwarf unwinders'. */
+
+static void
+show_dwarf_unwinders_enabled_p (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c,
+ const char *value)
+{
+ fprintf_filtered (file,
+ _("The DWARF stack unwinders are currently %s.\n"),
+ value);
+}
void
_initialize_dwarf2_frame (void)
{
dwarf2_frame_data = gdbarch_data_register_pre_init (dwarf2_frame_init);
- dwarf2_frame_objfile_data = register_objfile_data ();
+
+ add_setshow_boolean_cmd ("unwinders", class_obscure,
+ &dwarf2_frame_unwinders_enabled_p , _("\
+Set whether the DWARF stack frame unwinders are used."), _("\
+Show whether the DWARF stack frame unwinders are used."), _("\
+When enabled the DWARF stack frame unwinders can be used for architectures\n\
+that support the DWARF unwinders. Enabling the DWARF unwinders for an\n\
+architecture that doesn't support them will have no effect."),
+ NULL,
+ show_dwarf_unwinders_enabled_p,
+ &set_dwarf_cmdlist,
+ &show_dwarf_cmdlist);
+
+#if GDB_SELF_TEST
+ selftests::register_test_foreach_arch ("execute_cfa_program",
+ selftests::execute_cfa_program_test);
+#endif
}
projects / deliverable / binutils-gdb.git / blobdiff