-/* 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, 2003 Free Software Foundation, Inc.
This file is part of GDB.
#include "value.h"
#include "regcache.h"
#include "inferior.h"
+#include "reggroups.h"
/* For i386_linux_skip_solib_resolver. */
#include "symtab.h"
#include "solib-svr4.h" /* For struct link_map_offsets. */
+#include "osabi.h"
+
+#include "i386-tdep.h"
+#include "i386-linux-tdep.h"
+
/* Return the name of register REG. */
-char *
+static const char *
i386_linux_register_name (int reg)
{
/* Deal with the extra "orig_eax" pseudo register. */
return i386_register_name (reg);
}
-int
-i386_linux_register_byte (int reg)
+/* Return non-zero, when the register is in the corresponding register
+ group. Put the LINUX_ORIG_EAX register in the system group. */
+static int
+i386_linux_register_reggroup_p (struct gdbarch *gdbarch, int regnum,
+ struct reggroup *group)
{
- /* 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);
+ if (regnum == I386_LINUX_ORIG_EAX_REGNUM)
+ return (group == system_reggroup
+ || group == save_reggroup
+ || group == restore_reggroup);
+ return i386_register_reggroup_p (gdbarch, regnum, group);
}
-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);
-
- return (i386_linux_sigtramp_start (pc) != 0
- || i386_linux_rt_sigtramp_start (pc) != 0);
+ /* If we have NAME, we can optimize the search. The trampolines are
+ named __restore and __restore_rt. However, they aren't dynamically
+ exported from the shared C library, so the trampoline may appear to
+ be part of the preceding function. This should always be sigaction,
+ __sigaction, or __libc_sigaction (all aliases to the same function). */
+ if (name == NULL || strstr (name, "sigaction") != NULL)
+ return (i386_linux_sigtramp_start (pc) != 0
+ || i386_linux_rt_sigtramp_start (pc) != 0);
+
+ return (strcmp ("__restore", name) == 0
+ || strcmp ("__restore_rt", name) == 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
+static CORE_ADDR
i386_linux_sigcontext_addr (struct frame_info *frame)
{
CORE_ADDR pc;
- pc = i386_linux_sigtramp_start (frame->pc);
+ pc = i386_linux_sigtramp_start (get_frame_pc (frame));
if (pc)
{
CORE_ADDR sp;
- if (frame->next)
+ if (get_next_frame (frame))
/* If this isn't the top frame, the next frame must be for the
signal handler itself. The sigcontext structure lives on
the stack, right after the signum argument. */
- return frame->next->frame + 12;
+ return get_frame_base (get_next_frame (frame)) + 12;
/* This is the top frame. We'll have to find the address of the
sigcontext structure by looking at the stack pointer. Keep
"pop %eax". If the PC is at this instruction, adjust the
returned value accordingly. */
sp = read_register (SP_REGNUM);
- if (pc == frame->pc)
+ if (pc == get_frame_pc (frame))
return sp + 4;
return sp;
}
- pc = i386_linux_rt_sigtramp_start (frame->pc);
+ pc = i386_linux_rt_sigtramp_start (get_frame_pc (frame));
if (pc)
{
- if (frame->next)
+ if (get_next_frame (frame))
/* If this isn't the top frame, the next frame must be for the
signal handler itself. The sigcontext structure is part of
the user context. A pointer to the user context is passed
as the third argument to the signal handler. */
- return read_memory_integer (frame->next->frame + 16, 4) + 20;
+ return read_memory_integer (get_frame_base (get_next_frame (frame))
+ + 16, 4) + 20;
/* This is the top frame. Again, use the stack pointer to find
the address of the sigcontext structure. */
return 0;
}
-/* 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. */
-
-static CORE_ADDR
-i386_linux_sigtramp_saved_pc (struct frame_info *frame)
-{
- CORE_ADDR addr;
- addr = i386_linux_sigcontext_addr (frame);
- return read_memory_integer (addr + LINUX_SIGCONTEXT_PC_OFFSET, 4);
-}
-
-/* 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. */
-
-static CORE_ADDR
-i386_linux_sigtramp_saved_sp (struct frame_info *frame)
-{
- CORE_ADDR addr;
- addr = i386_linux_sigcontext_addr (frame);
- return read_memory_integer (addr + LINUX_SIGCONTEXT_SP_OFFSET, 4);
-}
-
-/* Signal trampolines don't have a meaningful frame. As in
- "i386/tm-i386.h", the frame pointer value we use is actually the
- frame pointer of the calling frame -- that is, the frame which was
- 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.
-
- When a signal trampoline is invoked from a frameless function, we
- essentially have two frameless functions in a row. In this case,
- we use the same magic cookie for three frames in a row. We detect
- this case by seeing whether the next frame has
- SIGNAL_HANDLER_CALLER set, and, if it does, checking whether the
- current frame is actually frameless. In this case, we need to get
- the PC by looking at the SP register value stored in the signal
- context.
-
- This should work in most cases except in horrible situations where
- a signal occurs just as we enter a function but before the frame
- has been set up. */
-
-#define FRAMELESS_SIGNAL(frame) \
- ((frame)->next != NULL \
- && (frame)->next->signal_handler_caller \
- && frameless_look_for_prologue (frame))
-
-CORE_ADDR
-i386_linux_frame_chain (struct frame_info *frame)
-{
- if (frame->signal_handler_caller || FRAMELESS_SIGNAL (frame))
- return frame->frame;
-
- if (! inside_entry_file (frame->pc))
- return read_memory_unsigned_integer (frame->frame, 4);
-
- return 0;
-}
-
-/* Return the saved program counter for FRAME. */
-
-CORE_ADDR
-i386_linux_frame_saved_pc (struct frame_info *frame)
-{
- if (frame->signal_handler_caller)
- return i386_linux_sigtramp_saved_pc (frame);
-
- if (FRAMELESS_SIGNAL (frame))
- {
- CORE_ADDR sp = i386_linux_sigtramp_saved_sp (frame->next);
- return read_memory_unsigned_integer (sp, 4);
- }
-
- return read_memory_unsigned_integer (frame->frame + 4, 4);
-}
-
-/* Immediately after a function call, return the saved pc. */
-
-CORE_ADDR
-i386_linux_saved_pc_after_call (struct frame_info *frame)
-{
- if (frame->signal_handler_caller)
- return i386_linux_sigtramp_saved_pc (frame);
-
- return read_memory_unsigned_integer (read_register (SP_REGNUM), 4);
-}
-
/* Set the program counter for process PTID to PC. */
-void
+static void
i386_linux_write_pc (CORE_ADDR pc, ptid_t ptid)
{
write_register_pid (PC_REGNUM, pc, ptid);
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_reggroup_p (gdbarch, i386_linux_register_reggroup_p);
+ set_gdbarch_register_bytes (gdbarch, I386_SSE_SIZEOF_REGS + 4);
+
+ tdep->jb_pc_offset = 20; /* From <bits/setjmp.h>. */
+
+ tdep->sigcontext_addr = i386_linux_sigcontext_addr;
+ tdep->sc_pc_offset = 14 * 4; /* From <asm/sigcontext.h>. */
+ tdep->sc_sp_offset = 7 * 4;
+
+ /* When the i386 Linux kernel calls a signal handler, the return
+ address points to a bit of code on the stack. This function is
+ 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_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, 0, GDB_OSABI_LINUX,
+ i386_linux_init_abi);
+}
projects / deliverable / binutils-gdb.git / blobdiff