| 1 | /* Native-dependent code for the i386. |
| 2 | |
| 3 | Low level functions to implement Oeprating System specific |
| 4 | code to manipulate I386 debug registers. |
| 5 | |
| 6 | Copyright (C) 2009-2012 Free Software Foundation, Inc. |
| 7 | |
| 8 | This file is part of GDB. |
| 9 | |
| 10 | This program is free software; you can redistribute it and/or modify |
| 11 | it under the terms of the GNU General Public License as published by |
| 12 | the Free Software Foundation; either version 3 of the License, or |
| 13 | (at your option) any later version. |
| 14 | |
| 15 | This program is distributed in the hope that it will be useful, |
| 16 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | GNU General Public License for more details. |
| 19 | |
| 20 | You should have received a copy of the GNU General Public License |
| 21 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 22 | |
| 23 | #include "defs.h" |
| 24 | |
| 25 | #ifndef I386_NAT_H |
| 26 | #define I386_NAT_H 1 |
| 27 | |
| 28 | /* Hardware-assisted breakpoints and watchpoints. */ |
| 29 | |
| 30 | /* Add watchpoint methods to the provided target_ops. |
| 31 | Targets using i386 family debug registers for watchpoints should call |
| 32 | this. */ |
| 33 | struct target_ops; |
| 34 | extern void i386_use_watchpoints (struct target_ops *); |
| 35 | |
| 36 | /* Support for hardware watchpoints and breakpoints using the i386 |
| 37 | debug registers. |
| 38 | |
| 39 | This provides several functions for inserting and removing |
| 40 | hardware-assisted breakpoints and watchpoints, testing if one or |
| 41 | more of the watchpoints triggered and at what address, checking |
| 42 | whether a given region can be watched, etc. |
| 43 | |
| 44 | In addition, each target should provide several low-level functions |
| 45 | regrouped into i386_dr_low_type struct below. These functions |
| 46 | that will be called to insert watchpoints and hardware breakpoints |
| 47 | into the inferior, remove them, and check their status. These |
| 48 | functions are: |
| 49 | |
| 50 | set_control -- set the debug control (DR7) |
| 51 | register to a given value for all LWPs |
| 52 | |
| 53 | set_addr -- put an address into one debug |
| 54 | register for all LWPs |
| 55 | |
| 56 | get_addr -- return the address in a given debug |
| 57 | register of the current LWP |
| 58 | |
| 59 | get_status -- return the value of the debug |
| 60 | status (DR6) register for current LWP |
| 61 | |
| 62 | get_control -- return the value of the debug |
| 63 | control (DR7) register for current LWP |
| 64 | |
| 65 | Additionally, the native file should set the debug_register_length |
| 66 | field to 4 or 8 depending on the number of bytes used for |
| 67 | deubg registers. */ |
| 68 | |
| 69 | struct i386_dr_low_type |
| 70 | { |
| 71 | void (*set_control) (unsigned long); |
| 72 | void (*set_addr) (int, CORE_ADDR); |
| 73 | CORE_ADDR (*get_addr) (int); |
| 74 | unsigned long (*get_status) (void); |
| 75 | unsigned long (*get_control) (void); |
| 76 | int debug_register_length; |
| 77 | }; |
| 78 | |
| 79 | extern struct i386_dr_low_type i386_dr_low; |
| 80 | |
| 81 | /* Debug registers' indices. */ |
| 82 | #define DR_FIRSTADDR 0 |
| 83 | #define DR_LASTADDR 3 |
| 84 | #define DR_NADDR 4 /* The number of debug address registers. */ |
| 85 | #define DR_STATUS 6 /* Index of debug status register (DR6). */ |
| 86 | #define DR_CONTROL 7 /* Index of debug control register (DR7). */ |
| 87 | |
| 88 | /* Global state needed to track h/w watchpoints. */ |
| 89 | |
| 90 | struct i386_debug_reg_state |
| 91 | { |
| 92 | /* Mirror the inferior's DRi registers. We keep the status and |
| 93 | control registers separated because they don't hold addresses. |
| 94 | Note that since we can change these mirrors while threads are |
| 95 | running, we never trust them to explain a cause of a trap. |
| 96 | For that, we need to peek directly in the inferior registers. */ |
| 97 | CORE_ADDR dr_mirror[DR_NADDR]; |
| 98 | unsigned dr_status_mirror, dr_control_mirror; |
| 99 | |
| 100 | /* Reference counts for each debug register. */ |
| 101 | int dr_ref_count[DR_NADDR]; |
| 102 | }; |
| 103 | |
| 104 | /* Use this function to set i386_dr_low debug_register_length field |
| 105 | rather than setting it directly to check that the length is only |
| 106 | set once. It also enables the 'maint set/show show-debug-regs' |
| 107 | command. */ |
| 108 | |
| 109 | extern void i386_set_debug_register_length (int len); |
| 110 | |
| 111 | /* Use this function to reset the i386-nat.c debug register state. */ |
| 112 | |
| 113 | extern void i386_cleanup_dregs (void); |
| 114 | |
| 115 | /* Return a pointer to the the local mirror of the inferior's debug |
| 116 | registers. */ |
| 117 | |
| 118 | extern struct i386_debug_reg_state *i386_debug_reg_state (void); |
| 119 | |
| 120 | #endif /* I386_NAT_H */ |