/* Target-dependent code for GNU/Linux running on i386's, for GDB.
- Copyright 2000, 2001, 2002 Free Software Foundation, Inc.
+ 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 "osabi.h"
+#include "reggroups.h"
+#include "solib-svr4.h"
-/* For i386_linux_skip_solib_resolver. */
-#include "symtab.h"
-#include "symfile.h"
-#include "objfiles.h"
-
-#include "solib-svr4.h" /* For struct link_map_offsets. */
+#include "gdb_string.h"
#include "i386-tdep.h"
#include "i386-linux-tdep.h"
+#include "glibc-tdep.h"
/* Return the name of register REG. */
return i386_register_name (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)
+{
+ 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);
+}
+
\f
/* Recognizing signal handler frames. */
The instruction sequence for normal signals is
pop %eax
- mov $0x77,%eax
+ mov $0x77, %eax
int $0x80
or 0x58 0xb8 0x77 0x00 0x00 0x00 0xcd 0x80.
to the ones used by the kernel. Therefore, these trampolines are
supported too. */
-#define LINUX_SIGTRAMP_INSN0 (0x58) /* pop %eax */
-#define LINUX_SIGTRAMP_OFFSET0 (0)
-#define LINUX_SIGTRAMP_INSN1 (0xb8) /* mov $NNNN,%eax */
-#define LINUX_SIGTRAMP_OFFSET1 (1)
-#define LINUX_SIGTRAMP_INSN2 (0xcd) /* int */
-#define LINUX_SIGTRAMP_OFFSET2 (6)
+#define LINUX_SIGTRAMP_INSN0 0x58 /* pop %eax */
+#define LINUX_SIGTRAMP_OFFSET0 0
+#define LINUX_SIGTRAMP_INSN1 0xb8 /* mov $NNNN, %eax */
+#define LINUX_SIGTRAMP_OFFSET1 1
+#define LINUX_SIGTRAMP_INSN2 0xcd /* int */
+#define LINUX_SIGTRAMP_OFFSET2 6
static const unsigned char linux_sigtramp_code[] =
{
LINUX_SIGTRAMP_INSN0, /* pop %eax */
- LINUX_SIGTRAMP_INSN1, 0x77, 0x00, 0x00, 0x00, /* mov $0x77,%eax */
+ LINUX_SIGTRAMP_INSN1, 0x77, 0x00, 0x00, 0x00, /* mov $0x77, %eax */
LINUX_SIGTRAMP_INSN2, 0x80 /* int $0x80 */
};
/* This function does the same for RT signals. Here the instruction
sequence is
- mov $0xad,%eax
+ mov $0xad, %eax
int $0x80
or 0xb8 0xad 0x00 0x00 0x00 0xcd 0x80.
The effect is to call the system call rt_sigreturn. */
-#define LINUX_RT_SIGTRAMP_INSN0 (0xb8) /* mov $NNNN,%eax */
-#define LINUX_RT_SIGTRAMP_OFFSET0 (0)
-#define LINUX_RT_SIGTRAMP_INSN1 (0xcd) /* int */
-#define LINUX_RT_SIGTRAMP_OFFSET1 (5)
+#define LINUX_RT_SIGTRAMP_INSN0 0xb8 /* mov $NNNN, %eax */
+#define LINUX_RT_SIGTRAMP_OFFSET0 0
+#define LINUX_RT_SIGTRAMP_INSN1 0xcd /* int */
+#define LINUX_RT_SIGTRAMP_OFFSET1 5
static const unsigned char linux_rt_sigtramp_code[] =
{
- LINUX_RT_SIGTRAMP_INSN0, 0xad, 0x00, 0x00, 0x00, /* mov $0xad,%eax */
+ LINUX_RT_SIGTRAMP_INSN0, 0xad, 0x00, 0x00, 0x00, /* mov $0xad, %eax */
LINUX_RT_SIGTRAMP_INSN1, 0x80 /* int $0x80 */
};
|| strcmp ("__restore_rt", name) == 0);
}
-/* Assuming FRAME is for a GNU/Linux sigtramp routine, return the
- address of the associated sigcontext structure. */
+/* Offset to struct sigcontext in ucontext, from <asm/ucontext.h>. */
+#define I386_LINUX_UCONTEXT_SIGCONTEXT_OFFSET 20
+
+/* Assuming NEXT_FRAME is a frame following a GNU/Linux sigtramp
+ routine, return the address of the associated sigcontext structure. */
static CORE_ADDR
-i386_linux_sigcontext_addr (struct frame_info *frame)
+i386_linux_sigcontext_addr (struct frame_info *next_frame)
{
CORE_ADDR pc;
+ CORE_ADDR sp;
+ char buf[4];
+
+ frame_unwind_register (next_frame, I386_ESP_REGNUM, buf);
+ sp = extract_unsigned_integer (buf, 4);
- pc = i386_linux_sigtramp_start (frame->pc);
+ pc = i386_linux_sigtramp_start (frame_pc_unwind (next_frame));
if (pc)
{
- CORE_ADDR sp;
-
- if (frame->next)
- /* 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;
-
- /* This is the top frame. We'll have to find the address of the
- sigcontext structure by looking at the stack pointer. Keep
- in mind that the first instruction of the sigtramp code is
- "pop %eax". If the PC is at this instruction, adjust the
- returned value accordingly. */
- sp = read_register (SP_REGNUM);
- if (pc == frame->pc)
+ /* The sigcontext structure lives on the stack, right after
+ the signum argument. We determine the address of the
+ sigcontext structure by looking at the frame's stack
+ pointer. Keep in mind that the first instruction of the
+ sigtramp code is "pop %eax". If the PC is after this
+ instruction, adjust the returned value accordingly. */
+ if (pc == frame_pc_unwind (next_frame))
return sp + 4;
return sp;
}
- pc = i386_linux_rt_sigtramp_start (frame->pc);
+ pc = i386_linux_rt_sigtramp_start (frame_pc_unwind (next_frame));
if (pc)
{
- if (frame->next)
- /* 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;
-
- /* This is the top frame. Again, use the stack pointer to find
- the address of the sigcontext structure. */
- return read_memory_integer (read_register (SP_REGNUM) + 8, 4) + 20;
+ CORE_ADDR ucontext_addr;
+
+ /* 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. */
+ read_memory (sp + 8, buf, 4);
+ ucontext_addr = extract_unsigned_integer (buf, 4);
+ return ucontext_addr + I386_LINUX_UCONTEXT_SIGCONTEXT_OFFSET;
}
error ("Couldn't recognize signal trampoline.");
static void
i386_linux_write_pc (CORE_ADDR pc, ptid_t ptid)
{
- write_register_pid (PC_REGNUM, pc, ptid);
+ write_register_pid (I386_EIP_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
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
- SOFUN_ADDRESS_MAYBE_TURQUOISE, ... Since this is so simple, it may
- be considered too special-purpose for general consumption. */
-
-static struct minimal_symbol *
-find_minsym_and_objfile (char *name, struct objfile **objfile_p)
-{
- struct objfile *objfile;
-
- ALL_OBJFILES (objfile)
- {
- struct minimal_symbol *msym;
-
- ALL_OBJFILE_MSYMBOLS (objfile, msym)
- {
- if (SYMBOL_NAME (msym)
- && STREQ (SYMBOL_NAME (msym), name))
- {
- *objfile_p = objfile;
- return msym;
- }
- }
- }
-
- return 0;
-}
-
-static CORE_ADDR
-skip_hurd_resolver (CORE_ADDR pc)
-{
- /* The HURD dynamic linker is part of the GNU C library, so many
- GNU/Linux distributions use it. (All ELF versions, as far as I
- know.) An unresolved PLT entry points to "_dl_runtime_resolve",
- which calls "fixup" to patch the PLT, and then passes control to
- the function.
-
- We look for the symbol `_dl_runtime_resolve', and find `fixup' in
- the same objfile. If we are at the entry point of `fixup', then
- we set a breakpoint at the return address (at the top of the
- stack), and continue.
-
- 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 GNU/Linux will provide a portable, efficient interface for
- debugging programs that use shared libraries. */
-
- struct objfile *objfile;
- struct minimal_symbol *resolver
- = find_minsym_and_objfile ("_dl_runtime_resolve", &objfile);
-
- if (resolver)
- {
- struct minimal_symbol *fixup
- = lookup_minimal_symbol ("fixup", NULL, objfile);
-
- if (fixup && SYMBOL_VALUE_ADDRESS (fixup) == pc)
- return (SAVED_PC_AFTER_CALL (get_current_frame ()));
- }
-
- return 0;
-}
-
-/* See the comments for SKIP_SOLIB_RESOLVER at the top of infrun.c.
- This function:
- 1) decides whether a PLT has sent us into the linker to resolve
- a function reference, and
- 2) if so, tells us where to set a temporary breakpoint that will
- trigger when the dynamic linker is done. */
-
-CORE_ADDR
-i386_linux_skip_solib_resolver (CORE_ADDR pc)
-{
- CORE_ADDR result;
-
- /* Plug in functions for other kinds of resolvers here. */
- result = skip_hurd_resolver (pc);
- if (result)
- return result;
-
- return 0;
-}
-
/* Fetch (and possibly build) an appropriate link_map_offsets
structure for native GNU/Linux x86 targets using the struct offsets
defined in link.h (but without actual reference to that file).
}
\f
+/* The register sets used in GNU/Linux ELF core-dumps are identical to
+ the register sets in `struct user' that are used for a.out
+ core-dumps. These are also used by ptrace(2). The corresponding
+ types are `elf_gregset_t' for the general-purpose registers (with
+ `elf_greg_t' the type of a single GP register) and `elf_fpregset_t'
+ for the floating-point registers.
+
+ Those types used to be available under the names `gregset_t' and
+ `fpregset_t' too, and GDB used those names in the past. But those
+ names are now used for the register sets used in the `mcontext_t'
+ type, which have a different size and layout. */
+
+/* Mapping between the general-purpose registers in `struct user'
+ format and GDB's register cache layout. */
+
+/* From <sys/reg.h>. */
+static int i386_linux_gregset_reg_offset[] =
+{
+ 6 * 4, /* %eax */
+ 1 * 4, /* %ecx */
+ 2 * 4, /* %edx */
+ 0 * 4, /* %ebx */
+ 15 * 4, /* %esp */
+ 5 * 4, /* %ebp */
+ 3 * 4, /* %esi */
+ 4 * 4, /* %edi */
+ 12 * 4, /* %eip */
+ 14 * 4, /* %eflags */
+ 13 * 4, /* %cs */
+ 16 * 4, /* %ss */
+ 7 * 4, /* %ds */
+ 8 * 4, /* %es */
+ 9 * 4, /* %fs */
+ 10 * 4, /* %gs */
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ -1,
+ 11 * 4 /* "orig_eax" */
+};
+
+/* Mapping between the general-purpose registers in `struct
+ sigcontext' format and GDB's register cache layout. */
+
+/* From <asm/sigcontext.h>. */
+static int i386_linux_sc_reg_offset[] =
+{
+ 11 * 4, /* %eax */
+ 10 * 4, /* %ecx */
+ 9 * 4, /* %edx */
+ 8 * 4, /* %ebx */
+ 7 * 4, /* %esp */
+ 6 * 4, /* %ebp */
+ 5 * 4, /* %esi */
+ 4 * 4, /* %edi */
+ 14 * 4, /* %eip */
+ 16 * 4, /* %eflags */
+ 15 * 4, /* %cs */
+ 18 * 4, /* %ss */
+ 3 * 4, /* %ds */
+ 2 * 4, /* %es */
+ 1 * 4, /* %fs */
+ 0 * 4 /* %gs */
+};
+
static void
i386_linux_init_abi (struct gdbarch_info info, struct gdbarch *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_num_regs (gdbarch, I386_LINUX_NUM_REGS);
set_gdbarch_register_name (gdbarch, i386_linux_register_name);
- set_gdbarch_register_bytes (gdbarch, I386_SSE_SIZEOF_REGS + 4);
+ set_gdbarch_register_reggroup_p (gdbarch, i386_linux_register_reggroup_p);
+
+ tdep->gregset_reg_offset = i386_linux_gregset_reg_offset;
+ tdep->gregset_num_regs = ARRAY_SIZE (i386_linux_gregset_reg_offset);
+ tdep->sizeof_gregset = 17 * 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;
+ tdep->sc_reg_offset = i386_linux_sc_reg_offset;
+ tdep->sc_num_regs = ARRAY_SIZE (i386_linux_sc_reg_offset);
/* When the i386 Linux kernel calls a signal handler, the return
address points to a bit of code on the stack. This function is
to support backtracing through calls to signal handlers. */
set_gdbarch_pc_in_sigtramp (gdbarch, i386_linux_pc_in_sigtramp);
+ set_gdbarch_skip_solib_resolver (gdbarch, glibc_skip_solib_resolver);
set_solib_svr4_fetch_link_map_offsets (gdbarch,
i386_linux_svr4_fetch_link_map_offsets);
}
void
_initialize_i386_linux_tdep (void)
{
- gdbarch_register_osabi (bfd_arch_i386, GDB_OSABI_LINUX,
+ gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_LINUX,
i386_linux_init_abi);
}
projects / deliverable / binutils-gdb.git / blobdiff