| /* Intel 386 native support for System V systems (pre-SVR4). |
| |
| Copyright 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1998, |
| 1999, 2000, 2002 Free Software Foundation, Inc. |
| |
| This file is part of GDB. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| 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. */ |
| |
| #include "defs.h" |
| |
| #ifdef HAVE_PTRACE_H |
| #include <ptrace.h> |
| #else |
| #ifdef HAVE_SYS_PTRACE_H |
| #include <sys/ptrace.h> |
| #endif |
| #endif |
| |
| #include "frame.h" |
| #include "inferior.h" |
| #include "language.h" |
| #include "gdbcore.h" |
| |
| #ifdef USG |
| #include <sys/types.h> |
| #endif |
| |
| #include <sys/param.h> |
| #include <sys/dir.h> |
| #include <signal.h> |
| #include <sys/user.h> |
| #include <sys/ioctl.h> |
| #include <fcntl.h> |
| |
| #ifdef TARGET_HAS_HARDWARE_WATCHPOINTS |
| #include <sys/debugreg.h> |
| #endif |
| |
| #include <sys/file.h> |
| #include "gdb_stat.h" |
| |
| #ifdef HAVE_SYS_REG_H |
| #include <sys/reg.h> |
| #endif |
| |
| #include "floatformat.h" |
| |
| #include "target.h" |
| |
| #include "i386-tdep.h" |
| |
| |
| /* Mapping between the general-purpose registers in `struct user' |
| format and GDB's register array layout. */ |
| static int regmap[] = |
| { |
| EAX, ECX, EDX, EBX, |
| UESP, EBP, ESI, EDI, |
| EIP, EFL, CS, SS, |
| DS, ES, FS, GS, |
| }; |
| |
| /* Support for the user struct. */ |
| |
| /* Return the address of register REGNUM. BLOCKEND is the value of |
| u.u_ar0, and points to the place where GS is stored. */ |
| |
| CORE_ADDR |
| register_u_addr (CORE_ADDR blockend, int regnum) |
| { |
| struct user u; |
| CORE_ADDR fpstate; |
| |
| if (i386_fp_regnum_p (regnum)) |
| { |
| #ifdef KSTKSZ /* SCO, and others? */ |
| blockend += 4 * (SS + 1) - KSTKSZ; |
| fpstate = blockend + ((char *) &u.u_fps.u_fpstate - (char *) &u); |
| return (fpstate + 0x1c + 10 * (regnum - FP0_REGNUM)); |
| #else |
| fpstate = blockend + ((char *) &u.i387.st_space - (char *) &u); |
| return (fpstate + 10 * (regnum - FP0_REGNUM)); |
| #endif |
| } |
| |
| return (blockend + 4 * regmap[regnum]); |
| } |
| |
| /* Return the size of the user struct. */ |
| |
| int |
| kernel_u_size (void) |
| { |
| return (sizeof (struct user)); |
| } |
| |
| #ifdef TARGET_HAS_HARDWARE_WATCHPOINTS |
| |
| #if !defined (offsetof) |
| #define offsetof(TYPE, MEMBER) ((unsigned long) &((TYPE *)0)->MEMBER) |
| #endif |
| |
| /* Record the value of the debug control register. */ |
| static int debug_control_mirror; |
| |
| /* Record which address associates with which register. */ |
| static CORE_ADDR address_lookup[DR_LASTADDR - DR_FIRSTADDR + 1]; |
| |
| static int i386_insert_aligned_watchpoint (int, CORE_ADDR, CORE_ADDR, int, |
| int); |
| |
| static int i386_insert_nonaligned_watchpoint (int, CORE_ADDR, CORE_ADDR, int, |
| int); |
| |
| /* Insert a watchpoint. */ |
| |
| int |
| i386_insert_watchpoint (int pid, CORE_ADDR addr, int len, int rw) |
| { |
| return i386_insert_aligned_watchpoint (pid, addr, addr, len, rw); |
| } |
| |
| static int |
| i386_insert_aligned_watchpoint (int pid, CORE_ADDR waddr, CORE_ADDR addr, |
| int len, int rw) |
| { |
| int i; |
| int read_write_bits, len_bits; |
| int free_debug_register; |
| int register_number; |
| |
| /* Look for a free debug register. */ |
| for (i = DR_FIRSTADDR; i <= DR_LASTADDR; i++) |
| { |
| if (address_lookup[i - DR_FIRSTADDR] == 0) |
| break; |
| } |
| |
| /* No more debug registers! */ |
| if (i > DR_LASTADDR) |
| return -1; |
| |
| read_write_bits = (rw & 1) ? DR_RW_READ : DR_RW_WRITE; |
| |
| if (len == 1) |
| len_bits = DR_LEN_1; |
| else if (len == 2) |
| { |
| if (addr % 2) |
| return i386_insert_nonaligned_watchpoint (pid, waddr, addr, len, rw); |
| len_bits = DR_LEN_2; |
| } |
| |
| else if (len == 4) |
| { |
| if (addr % 4) |
| return i386_insert_nonaligned_watchpoint (pid, waddr, addr, len, rw); |
| len_bits = DR_LEN_4; |
| } |
| else |
| return i386_insert_nonaligned_watchpoint (pid, waddr, addr, len, rw); |
| |
| free_debug_register = i; |
| register_number = free_debug_register - DR_FIRSTADDR; |
| debug_control_mirror |= |
| ((read_write_bits | len_bits) |
| << (DR_CONTROL_SHIFT + DR_CONTROL_SIZE * register_number)); |
| debug_control_mirror |= |
| (1 << (DR_LOCAL_ENABLE_SHIFT + DR_ENABLE_SIZE * register_number)); |
| debug_control_mirror |= DR_LOCAL_SLOWDOWN; |
| debug_control_mirror &= ~DR_CONTROL_RESERVED; |
| |
| ptrace (6, pid, offsetof (struct user, u_debugreg[DR_CONTROL]), |
| debug_control_mirror); |
| ptrace (6, pid, offsetof (struct user, u_debugreg[free_debug_register]), |
| addr); |
| |
| /* Record where we came from. */ |
| address_lookup[register_number] = addr; |
| return 0; |
| } |
| |
| static int |
| i386_insert_nonaligned_watchpoint (int pid, CORE_ADDR waddr, CORE_ADDR addr, |
| int len, int rw) |
| { |
| int align; |
| int size; |
| int rv; |
| |
| static int size_try_array[4][4] = |
| { |
| { 1, 1, 1, 1 }, /* trying size one */ |
| { 2, 1, 2, 1 }, /* trying size two */ |
| { 2, 1, 2, 1 }, /* trying size three */ |
| { 4, 1, 2, 1 } /* trying size four */ |
| }; |
| |
| rv = 0; |
| while (len > 0) |
| { |
| align = addr % 4; |
| /* Four is the maximum length for 386. */ |
| size = size_try_array[len > 4 ? 3 : len - 1][align]; |
| |
| rv = i386_insert_aligned_watchpoint (pid, waddr, addr, size, rw); |
| if (rv) |
| { |
| i386_remove_watchpoint (pid, waddr, size); |
| return rv; |
| } |
| addr += size; |
| len -= size; |
| } |
| return rv; |
| } |
| |
| /* Remove a watchpoint. */ |
| |
| int |
| i386_remove_watchpoint (int pid, CORE_ADDR addr, int len) |
| { |
| int i; |
| int register_number; |
| |
| for (i = DR_FIRSTADDR; i <= DR_LASTADDR; i++) |
| { |
| register_number = i - DR_FIRSTADDR; |
| if (address_lookup[register_number] == addr) |
| { |
| debug_control_mirror &= |
| ~(1 << (DR_LOCAL_ENABLE_SHIFT + DR_ENABLE_SIZE * register_number)); |
| address_lookup[register_number] = 0; |
| } |
| } |
| ptrace (6, pid, offsetof (struct user, u_debugreg[DR_CONTROL]), |
| debug_control_mirror); |
| ptrace (6, pid, offsetof (struct user, u_debugreg[DR_STATUS]), 0); |
| |
| return 0; |
| } |
| |
| /* Check if stopped by a watchpoint. */ |
| |
| CORE_ADDR |
| i386_stopped_by_watchpoint (int pid) |
| { |
| int i; |
| int status; |
| |
| status = ptrace (3, pid, offsetof (struct user, u_debugreg[DR_STATUS]), 0); |
| ptrace (6, pid, offsetof (struct user, u_debugreg[DR_STATUS]), 0); |
| |
| for (i = DR_FIRSTADDR; i <= DR_LASTADDR; i++) |
| { |
| if (status & (1 << (i - DR_FIRSTADDR))) |
| return address_lookup[i - DR_FIRSTADDR]; |
| } |
| |
| return 0; |
| } |
| |
| #endif /* TARGET_HAS_HARDWARE_WATCHPOINTS */ |