/* GNU/Linux on ARM target support.
- Copyright 1999, 2000, 2001, 2002, 2003, 2005 Free Software
- Foundation, Inc.
+ Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
+ Free Software Foundation, Inc.
This file is part of GDB.
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. */
+ Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA. */
#include "defs.h"
#include "target.h"
#include "doublest.h"
#include "solib-svr4.h"
#include "osabi.h"
+#include "trad-frame.h"
+#include "tramp-frame.h"
#include "arm-tdep.h"
#include "glibc-tdep.h"
+#include "gdb_string.h"
+
/* Under ARM GNU/Linux the traditional way of performing a breakpoint
is to execute a particular software interrupt, rather than use a
particular undefined instruction to provoke a trap. Upon exection
static const char arm_linux_arm_be_breakpoint[] = { 0xef, 0x9f, 0x00, 0x01 };
+/* However, the EABI syscall interface (new in Nov. 2005) does not look at
+ the operand of the swi if old-ABI compatibility is disabled. Therefore,
+ use an undefined instruction instead. This is supported as of kernel
+ version 2.5.70 (May 2003), so should be a safe assumption for EABI
+ binaries. */
+
+static const char eabi_linux_arm_le_breakpoint[] = { 0xf0, 0x01, 0xf0, 0xe7 };
+
+static const char eabi_linux_arm_be_breakpoint[] = { 0xe7, 0xf0, 0x01, 0xf0 };
+
+/* All the kernels which support Thumb support using a specific undefined
+ instruction for the Thumb breakpoint. */
+
static const char arm_linux_thumb_be_breakpoint[] = {0xde, 0x01};
static const char arm_linux_thumb_le_breakpoint[] = {0x01, 0xde};
with. Before the fixup/resolver code returns, it actually calls
the requested function and repairs &GOT[n+3]. */
-/* Fetch, and possibly build, an appropriate link_map_offsets structure
- for ARM linux targets using the struct offsets defined in <link.h>.
- Note, however, that link.h is not actually referred to in this file.
- Instead, the relevant structs offsets were obtained from examining
- link.h. (We can't refer to link.h from this file because the host
- system won't necessarily have it, or if it does, the structs which
- it defines will refer to the host system, not the target). */
-
-static struct link_map_offsets *
-arm_linux_svr4_fetch_link_map_offsets (void)
-{
- static struct link_map_offsets lmo;
- static struct link_map_offsets *lmp = 0;
-
- if (lmp == 0)
- {
- lmp = &lmo;
-
- lmo.r_debug_size = 8; /* Actual size is 20, but this is all we
- need. */
-
- lmo.r_map_offset = 4;
- lmo.r_map_size = 4;
-
- lmo.link_map_size = 20; /* Actual size is 552, but this is all we
- need. */
-
- lmo.l_addr_offset = 0;
- lmo.l_addr_size = 4;
-
- lmo.l_name_offset = 4;
- lmo.l_name_size = 4;
-
- lmo.l_next_offset = 12;
- lmo.l_next_size = 4;
-
- lmo.l_prev_offset = 16;
- lmo.l_prev_size = 4;
- }
-
- return lmp;
-}
-
/* The constants below were determined by examining the following files
in the linux kernel sources:
#define ARM_LINUX_SIGRETURN_INSTR 0xef900077
#define ARM_LINUX_RT_SIGRETURN_INSTR 0xef9000ad
-/* arm_linux_in_sigtramp determines if PC points at one of the
- instructions which cause control to return to the Linux kernel upon
- return from a signal handler. FUNC_NAME is unused. */
+/* For ARM EABI, recognize the pattern that glibc uses... alternatively,
+ we could arrange to do this by function name, but they are not always
+ exported. */
+#define ARM_SET_R7_SIGRETURN 0xe3a07077
+#define ARM_SET_R7_RT_SIGRETURN 0xe3a070ad
+#define ARM_EABI_SYSCALL 0xef000000
-int
-arm_linux_in_sigtramp (CORE_ADDR pc, char *func_name)
+static void
+arm_linux_sigtramp_cache (struct frame_info *next_frame,
+ struct trad_frame_cache *this_cache,
+ CORE_ADDR func, int regs_offset)
{
- unsigned long inst;
+ CORE_ADDR sp = frame_unwind_register_unsigned (next_frame, ARM_SP_REGNUM);
+ CORE_ADDR base = sp + regs_offset;
+ int i;
- inst = read_memory_integer (pc, 4);
+ for (i = 0; i < 16; i++)
+ trad_frame_set_reg_addr (this_cache, i, base + i * 4);
- return (inst == ARM_LINUX_SIGRETURN_INSTR
- || inst == ARM_LINUX_RT_SIGRETURN_INSTR);
+ trad_frame_set_reg_addr (this_cache, ARM_PS_REGNUM, base + 16 * 4);
-}
+ /* The VFP or iWMMXt registers may be saved on the stack, but there's
+ no reliable way to restore them (yet). */
-/* arm_linux_sigcontext_register_address returns the address in the
- sigcontext of register REGNO given a stack pointer value SP and
- program counter value PC. The value 0 is returned if PC is not
- pointing at one of the signal return instructions or if REGNO is
- not saved in the sigcontext struct. */
+ /* Save a frame ID. */
+ trad_frame_set_id (this_cache, frame_id_build (sp, func));
+}
-CORE_ADDR
-arm_linux_sigcontext_register_address (CORE_ADDR sp, CORE_ADDR pc, int regno)
+static void
+arm_linux_sigreturn_init (const struct tramp_frame *self,
+ struct frame_info *next_frame,
+ struct trad_frame_cache *this_cache,
+ CORE_ADDR func)
{
- unsigned long inst;
- CORE_ADDR reg_addr = 0;
-
- inst = read_memory_integer (pc, 4);
-
- if (inst == ARM_LINUX_SIGRETURN_INSTR
- || inst == ARM_LINUX_RT_SIGRETURN_INSTR)
- {
- CORE_ADDR sigcontext_addr;
-
- /* The sigcontext structure is at different places for the two
- signal return instructions. For ARM_LINUX_SIGRETURN_INSTR,
- it starts at the SP value. For ARM_LINUX_RT_SIGRETURN_INSTR,
- it is at SP+8. For the latter instruction, it may also be
- the case that the address of this structure may be determined
- by reading the 4 bytes at SP, but I'm not convinced this is
- reliable.
-
- In any event, these magic constants (0 and 8) may be
- determined by examining struct sigframe and struct
- rt_sigframe in arch/arm/kernel/signal.c in the Linux kernel
- sources. */
-
- if (inst == ARM_LINUX_RT_SIGRETURN_INSTR)
- sigcontext_addr = sp + 8;
- else /* inst == ARM_LINUX_SIGRETURN_INSTR */
- sigcontext_addr = sp + 0;
-
- /* The layout of the sigcontext structure for ARM GNU/Linux is
- in include/asm-arm/sigcontext.h in the Linux kernel sources.
-
- There are three 4-byte fields which precede the saved r0
- field. (This accounts for the 12 in the code below.) The
- sixteen registers (4 bytes per field) follow in order. The
- PSR value follows the sixteen registers which accounts for
- the constant 19 below. */
-
- if (0 <= regno && regno <= ARM_PC_REGNUM)
- reg_addr = sigcontext_addr + 12 + (4 * regno);
- else if (regno == ARM_PS_REGNUM)
- reg_addr = sigcontext_addr + 19 * 4;
- }
+ arm_linux_sigtramp_cache (next_frame, this_cache, func,
+ 0x0c /* Offset to registers. */);
+}
- return reg_addr;
+static void
+arm_linux_rt_sigreturn_init (const struct tramp_frame *self,
+ struct frame_info *next_frame,
+ struct trad_frame_cache *this_cache,
+ CORE_ADDR func)
+{
+ arm_linux_sigtramp_cache (next_frame, this_cache, func,
+ 0x88 /* Offset to ucontext_t. */
+ + 0x14 /* Offset to sigcontext. */
+ + 0x0c /* Offset to registers. */);
}
+static struct tramp_frame arm_linux_sigreturn_tramp_frame = {
+ SIGTRAMP_FRAME,
+ 4,
+ {
+ { ARM_LINUX_SIGRETURN_INSTR, -1 },
+ { TRAMP_SENTINEL_INSN }
+ },
+ arm_linux_sigreturn_init
+};
+
+static struct tramp_frame arm_linux_rt_sigreturn_tramp_frame = {
+ SIGTRAMP_FRAME,
+ 4,
+ {
+ { ARM_LINUX_RT_SIGRETURN_INSTR, -1 },
+ { TRAMP_SENTINEL_INSN }
+ },
+ arm_linux_rt_sigreturn_init
+};
+
+static struct tramp_frame arm_eabi_linux_sigreturn_tramp_frame = {
+ SIGTRAMP_FRAME,
+ 4,
+ {
+ { ARM_SET_R7_SIGRETURN, -1 },
+ { ARM_EABI_SYSCALL, -1 },
+ { TRAMP_SENTINEL_INSN }
+ },
+ arm_linux_sigreturn_init
+};
+
+static struct tramp_frame arm_eabi_linux_rt_sigreturn_tramp_frame = {
+ SIGTRAMP_FRAME,
+ 4,
+ {
+ { ARM_SET_R7_RT_SIGRETURN, -1 },
+ { ARM_EABI_SYSCALL, -1 },
+ { TRAMP_SENTINEL_INSN }
+ },
+ arm_linux_rt_sigreturn_init
+};
+
static void
arm_linux_init_abi (struct gdbarch_info info,
struct gdbarch *gdbarch)
tdep->lowest_pc = 0x8000;
if (info.byte_order == BFD_ENDIAN_BIG)
{
- tdep->arm_breakpoint = arm_linux_arm_be_breakpoint;
+ if (tdep->arm_abi == ARM_ABI_AAPCS)
+ tdep->arm_breakpoint = eabi_linux_arm_be_breakpoint;
+ else
+ tdep->arm_breakpoint = arm_linux_arm_be_breakpoint;
tdep->thumb_breakpoint = arm_linux_thumb_be_breakpoint;
}
else
{
- tdep->arm_breakpoint = arm_linux_arm_le_breakpoint;
+ if (tdep->arm_abi == ARM_ABI_AAPCS)
+ tdep->arm_breakpoint = eabi_linux_arm_le_breakpoint;
+ else
+ tdep->arm_breakpoint = arm_linux_arm_le_breakpoint;
tdep->thumb_breakpoint = arm_linux_thumb_le_breakpoint;
}
tdep->arm_breakpoint_size = sizeof (arm_linux_arm_le_breakpoint);
tdep->jb_elt_size = ARM_LINUX_JB_ELEMENT_SIZE;
set_solib_svr4_fetch_link_map_offsets
- (gdbarch, arm_linux_svr4_fetch_link_map_offsets);
+ (gdbarch, svr4_ilp32_fetch_link_map_offsets);
/* The following override shouldn't be needed. */
set_gdbarch_deprecated_extract_return_value (gdbarch, arm_linux_extract_return_value);
/* Enable TLS support. */
set_gdbarch_fetch_tls_load_module_address (gdbarch,
svr4_fetch_objfile_link_map);
+
+ tramp_frame_prepend_unwinder (gdbarch,
+ &arm_linux_sigreturn_tramp_frame);
+ tramp_frame_prepend_unwinder (gdbarch,
+ &arm_linux_rt_sigreturn_tramp_frame);
+ tramp_frame_prepend_unwinder (gdbarch,
+ &arm_eabi_linux_sigreturn_tramp_frame);
+ tramp_frame_prepend_unwinder (gdbarch,
+ &arm_eabi_linux_rt_sigreturn_tramp_frame);
}
void
projects / deliverable / binutils-gdb.git / blobdiff