/* Intel 386 native support for SYSV systems (pre-SVR4).
- Copyright (C) 1988, 1989, 1991, 1992 Free Software Foundation, Inc.
+ Copyright (C) 1988, 1989, 1991, 1992, 1994 Free Software Foundation, Inc.
This file is part of GDB.
#include <sys/ioctl.h>
#include <fcntl.h>
+#ifdef TARGET_HAS_HARDWARE_WATCHPOINTS
+#include <sys/debugreg.h>
+#endif
+
#include <sys/file.h>
#include <sys/stat.h>
return (blockend + 4 * regmap[regnum]);
}
+\f
+#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