-/* Target-dependent code for Linux running on i386's, for GDB.
- Copyright 2000, 2001 Free Software Foundation, Inc.
+/* Target-dependent code for GNU/Linux running on i386's, for GDB.
+
+ Copyright 2000, 2001, 2002 Free Software Foundation, Inc.
This file is part of GDB.
#include "frame.h"
#include "value.h"
#include "regcache.h"
+#include "inferior.h"
/* For i386_linux_skip_solib_resolver. */
#include "symtab.h"
#include "solib-svr4.h" /* For struct link_map_offsets. */
+#include "i386-tdep.h"
+#include "i386-linux-tdep.h"
+
+/* Return the name of register REG. */
+
+static const char *
+i386_linux_register_name (int reg)
+{
+ /* Deal with the extra "orig_eax" pseudo register. */
+ if (reg == I386_LINUX_ORIG_EAX_REGNUM)
+ return "orig_eax";
+
+ return i386_register_name (reg);
+}
+
+static int
+i386_linux_register_byte (int reg)
+{
+ /* Deal with the extra "orig_eax" pseudo register. */
+ if (reg == I386_LINUX_ORIG_EAX_REGNUM)
+ return (i386_register_byte (I386_LINUX_ORIG_EAX_REGNUM - 1)
+ + i386_register_raw_size (I386_LINUX_ORIG_EAX_REGNUM - 1));
+
+ return i386_register_byte (reg);
+}
+
+static int
+i386_linux_register_raw_size (int reg)
+{
+ /* Deal with the extra "orig_eax" pseudo register. */
+ if (reg == I386_LINUX_ORIG_EAX_REGNUM)
+ return 4;
+
+ return i386_register_raw_size (reg);
+}
\f
/* Recognizing signal handler frames. */
-/* Linux has two flavors of signals. Normal signal handlers, and
+/* GNU/Linux has two flavors of signals. Normal signal handlers, and
"realtime" (RT) signals. The RT signals can provide additional
information to the signal handler if the SA_SIGINFO flag is set
when establishing a signal handler using `sigaction'. It is not
- unlikely that future versions of Linux will support SA_SIGINFO for
- normal signals too. */
+ unlikely that future versions of GNU/Linux will support SA_SIGINFO
+ for normal signals too. */
/* When the i386 Linux kernel calls a signal handler and the
SA_RESTORER flag isn't set, the return address points to a bit of
It kind of sucks that we have to read memory from the process in
order to identify a signal trampoline, but there doesn't seem to be
- any other way. The IN_SIGTRAMP macro in tm-linux.h arranges to
+ any other way. The PC_IN_SIGTRAMP macro in tm-linux.h arranges to
only call us if no function name could be identified, which should
be the case since the code is on the stack.
return pc;
}
-/* Return whether PC is in a Linux sigtramp routine. */
+/* Return whether PC is in a GNU/Linux sigtramp routine. */
-int
-i386_linux_in_sigtramp (CORE_ADDR pc, char *name)
+static int
+i386_linux_pc_in_sigtramp (CORE_ADDR pc, char *name)
{
if (name)
return STREQ ("__restore", name) || STREQ ("__restore_rt", name);
|| i386_linux_rt_sigtramp_start (pc) != 0);
}
-/* Assuming FRAME is for a Linux sigtramp routine, return the address
- of the associated sigcontext structure. */
+/* Assuming FRAME is for a GNU/Linux sigtramp routine, return the
+ address of the associated sigcontext structure. */
CORE_ADDR
i386_linux_sigcontext_addr (struct frame_info *frame)
/* Offset to saved PC in sigcontext, from <asm/sigcontext.h>. */
#define LINUX_SIGCONTEXT_PC_OFFSET (56)
-/* Assuming FRAME is for a Linux sigtramp routine, return the saved
- program counter. */
+/* Assuming FRAME is for a GNU/Linux sigtramp routine, return the
+ saved program counter. */
static CORE_ADDR
i386_linux_sigtramp_saved_pc (struct frame_info *frame)
/* Offset to saved SP in sigcontext, from <asm/sigcontext.h>. */
#define LINUX_SIGCONTEXT_SP_OFFSET (28)
-/* Assuming FRAME is for a Linux sigtramp routine, return the saved
- stack pointer. */
+/* Assuming FRAME is for a GNU/Linux sigtramp routine, return the
+ saved stack pointer. */
static CORE_ADDR
i386_linux_sigtramp_saved_sp (struct frame_info *frame)
in progress when the signal trampoline was entered. GDB mostly
treats this frame pointer value as a magic cookie. We detect the
case of a signal trampoline by looking at the SIGNAL_HANDLER_CALLER
- field, which is set based on IN_SIGTRAMP.
+ field, which is set based on PC_IN_SIGTRAMP.
When a signal trampoline is invoked from a frameless function, we
essentially have two frameless functions in a row. In this case,
if (frame->signal_handler_caller)
return i386_linux_sigtramp_saved_pc (frame);
- return read_memory_integer (read_register (SP_REGNUM), 4);
+ return read_memory_unsigned_integer (read_register (SP_REGNUM), 4);
}
-\f
+/* Set the program counter for process PTID to PC. */
+
+static void
+i386_linux_write_pc (CORE_ADDR pc, ptid_t ptid)
+{
+ write_register_pid (PC_REGNUM, pc, ptid);
+
+ /* We must be careful with modifying the program counter. If we
+ just interrupted a system call, the kernel might try to restart
+ it when we resume the inferior. On restarting the system call,
+ the kernel will try backing up the program counter even though it
+ no longer points at the system call. This typically results in a
+ SIGSEGV or SIGILL. We can prevent this by writing `-1' in the
+ "orig_eax" pseudo-register.
+
+ Note that "orig_eax" is saved when setting up a dummy call frame.
+ This means that it is properly restored when that frame is
+ popped, and that the interrupted system call will be restarted
+ when we resume the inferior on return from a function call from
+ within GDB. In all other cases the system call will not be
+ restarted. */
+ write_register_pid (I386_LINUX_ORIG_EAX_REGNUM, -1, ptid);
+}
+\f
/* Calling functions in shared libraries. */
+
/* Find the minimal symbol named NAME, and return both the minsym
struct and its objfile. This probably ought to be in minsym.c, but
everything there is trying to deal with things like C++ and
It's kind of gross to do all these checks every time we're
called, since they don't change once the executable has gotten
started. But this is only a temporary hack --- upcoming versions
- of Linux will provide a portable, efficient interface for
+ of GNU/Linux will provide a portable, efficient interface for
debugging programs that use shared libraries. */
struct objfile *objfile;
if (resolver)
{
struct minimal_symbol *fixup
- = lookup_minimal_symbol ("fixup", 0, objfile);
+ = lookup_minimal_symbol ("fixup", NULL, objfile);
if (fixup && SYMBOL_VALUE_ADDRESS (fixup) == pc)
return (SAVED_PC_AFTER_CALL (get_current_frame ()));
}
/* Fetch (and possibly build) an appropriate link_map_offsets
- structure for native Linux/x86 targets using the struct offsets
+ structure for native GNU/Linux x86 targets using the struct offsets
defined in link.h (but without actual reference to that file).
- This makes it possible to access Linux/x86 shared libraries from a
- GDB that was not built on an Linux/x86 host (for cross debugging). */
+ This makes it possible to access GNU/Linux x86 shared libraries
+ from a GDB that was not built on an GNU/Linux x86 host (for cross
+ debugging). */
-struct link_map_offsets *
+static struct link_map_offsets *
i386_linux_svr4_fetch_link_map_offsets (void)
{
static struct link_map_offsets lmo;
return lmp;
}
+\f
+
+static void
+i386_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ /* GNU/Linux uses ELF. */
+ i386_elf_init_abi (info, gdbarch);
+
+ /* We support the SSE registers on GNU/Linux. */
+ tdep->num_xmm_regs = I386_NUM_XREGS - 1;
+ /* set_gdbarch_num_regs (gdbarch, I386_SSE_NUM_REGS); */
+
+ /* Since we have the extra "orig_eax" register on GNU/Linux, we have
+ to adjust a few things. */
+
+ set_gdbarch_write_pc (gdbarch, i386_linux_write_pc);
+ set_gdbarch_num_regs (gdbarch, I386_SSE_NUM_REGS + 1);
+ set_gdbarch_register_name (gdbarch, i386_linux_register_name);
+ set_gdbarch_register_bytes (gdbarch, I386_SSE_SIZEOF_REGS + 4);
+ set_gdbarch_register_byte (gdbarch, i386_linux_register_byte);
+ set_gdbarch_register_raw_size (gdbarch, i386_linux_register_raw_size);
+
+ tdep->jb_pc_offset = 20; /* From <bits/setjmp.h>. */
+
+ /* When the i386 Linux kernel calls a signal handler, the return
+ address points to a bit of code on the stack. These definitions
+ are used to identify this bit of code as a signal trampoline in
+ order to support backtracing through calls to signal handlers. */
+
+ set_gdbarch_pc_in_sigtramp (gdbarch, i386_linux_pc_in_sigtramp);
+ set_gdbarch_frame_chain (gdbarch, i386_linux_frame_chain);
+ set_gdbarch_frame_saved_pc (gdbarch, i386_linux_frame_saved_pc);
+ set_gdbarch_saved_pc_after_call (gdbarch, i386_linux_saved_pc_after_call);
+
+ set_solib_svr4_fetch_link_map_offsets (gdbarch,
+ i386_linux_svr4_fetch_link_map_offsets);
+}
+
+/* Provide a prototype to silence -Wmissing-prototypes. */
+extern void _initialize_i386_linux_tdep (void);
+
+void
+_initialize_i386_linux_tdep (void)
+{
+ gdbarch_register_osabi (bfd_arch_i386, GDB_OSABI_LINUX,
+ i386_linux_init_abi);
+}
projects / deliverable / binutils-gdb.git / blobdiff