/* GNU/Linux on ARM target support.
- Copyright (C) 1999, 2000, 2001, 2002, 2003, 2005 Free Software
- Foundation, Inc.
+ Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005
+ Free Software Foundation, Inc.
This file is part of GDB.
#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
#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)
/* 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