/* Intel 386 native support for SYSV systems (pre-SVR4). Copyright (C) 1988, 1989, 1991, 1992, 1994 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., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "defs.h" #include "frame.h" #include "inferior.h" #include "language.h" #include "gdbcore.h" #ifdef USG #include #endif #include #include #include #include #include #include #ifdef TARGET_HAS_HARDWARE_WATCHPOINTS #include #endif #include #include "gdb_stat.h" #ifndef NO_SYS_REG_H #include #endif #include "floatformat.h" #include "target.h" /* this table must line up with REGISTER_NAMES in tm-i386v.h */ /* symbols like 'EAX' come from */ static int regmap[] = { EAX, ECX, EDX, EBX, UESP, EBP, ESI, EDI, EIP, EFL, CS, SS, DS, ES, FS, GS, }; /* blockend is the value of u.u_ar0, and points to the * place where GS is stored */ int i386_register_u_addr (blockend, regnum) int blockend; int regnum; { #if 0 /* this will be needed if fp registers are reinstated */ /* for now, you can look at them with 'info float' * sys5 wont let you change them with ptrace anyway */ if (regnum >= FP0_REGNUM && regnum <= FP7_REGNUM) { int ubase, fpstate; struct user u; ubase = blockend + 4 * (SS + 1) - KSTKSZ; fpstate = ubase + ((char *)&u.u_fpstate - (char *)&u); return (fpstate + 0x1c + 10 * (regnum - FP0_REGNUM)); } else #endif return (blockend + 4 * regmap[regnum]); } #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 PARAMS ((int, CORE_ADDR, CORE_ADDR, int, int)); static int i386_insert_nonaligned_watchpoint PARAMS ((int, CORE_ADDR, CORE_ADDR, int, int)); /* Insert a watchpoint. */ int i386_insert_watchpoint (pid, addr, len, rw) 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 (pid, waddr, addr, len, rw) 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 : 0) | ((rw & 2) ? DR_RW_WRITE : 0); 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 (pid, waddr, addr, len, rw) int pid; CORE_ADDR waddr; CORE_ADDR addr; int len; int rw; { int align; int size; int rv; static int size_try_array[16] = { 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 = (len > 4) ? 3 : len - 1; size = size_try_array[size * 4 + 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 (pid, addr, len) 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 (pid) 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 */ #if 0 /* using FLOAT_INFO as is would be a problem. FLOAT_INFO is called via a command xxx and eventually calls ptrace without ever having traversed the target vector. This would be terribly impolite behaviour for a sun4 hosted remote gdb. A fix might be to move this code into the "info registers" command. rich@cygnus.com 15 Sept 92. */ i386_float_info () { struct user u; /* just for address computations */ int i; /* fpstate defined in */ struct fpstate *fpstatep; char buf[sizeof (struct fpstate) + 2 * sizeof (int)]; unsigned int uaddr; char fpvalid = 0; unsigned int rounded_addr; unsigned int rounded_size; extern int corechan; int skip; uaddr = (char *)&u.u_fpvalid - (char *)&u; if (target_has_execution) { unsigned int data; unsigned int mask; rounded_addr = uaddr & -sizeof (int); data = ptrace (3, inferior_pid, (PTRACE_ARG3_TYPE) rounded_addr, 0); mask = 0xff << ((uaddr - rounded_addr) * 8); fpvalid = ((data & mask) != 0); } #if 0 else { if (lseek (corechan, uaddr, 0) < 0) perror ("seek on core file"); if (myread (corechan, &fpvalid, 1) < 0) perror ("read on core file"); } #endif /* no core support yet */ if (fpvalid == 0) { printf_unfiltered ("no floating point status saved\n"); return; } uaddr = (char *)&U_FPSTATE(u) - (char *)&u; if (target_has_execution) { int *ip; rounded_addr = uaddr & -sizeof (int); rounded_size = (((uaddr + sizeof (struct fpstate)) - uaddr) + sizeof (int) - 1) / sizeof (int); skip = uaddr - rounded_addr; ip = (int *)buf; for (i = 0; i < rounded_size; i++) { *ip++ = ptrace (3, inferior_pid, (PTRACE_ARG3_TYPE) rounded_addr, 0); rounded_addr += sizeof (int); } } #if 0 else { if (lseek (corechan, uaddr, 0) < 0) perror_with_name ("seek on core file"); if (myread (corechan, buf, sizeof (struct fpstate)) < 0) perror_with_name ("read from core file"); skip = 0; } #endif /* 0 */ fpstatep = (struct fpstate *)(buf + skip); print_387_status (fpstatep->status, (struct env387 *)fpstatep->state); } #endif /* never */