1547 lines
45 KiB
C
1547 lines
45 KiB
C
/* Native-dependent code for GNU/Linux AArch64.
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Copyright (C) 2011-2015 Free Software Foundation, Inc.
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Contributed by ARM Ltd.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#include "defs.h"
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#include "inferior.h"
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#include "gdbcore.h"
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#include "regcache.h"
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#include "linux-nat.h"
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#include "target-descriptions.h"
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#include "auxv.h"
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#include "gdbcmd.h"
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#include "aarch64-tdep.h"
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#include "aarch64-linux-tdep.h"
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#include "elf/common.h"
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#include <sys/ptrace.h>
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#include <sys/utsname.h>
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#include <asm/ptrace.h>
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#include "gregset.h"
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/* Defines ps_err_e, struct ps_prochandle. */
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#include "gdb_proc_service.h"
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#ifndef TRAP_HWBKPT
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#define TRAP_HWBKPT 0x0004
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#endif
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/* On GNU/Linux, threads are implemented as pseudo-processes, in which
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case we may be tracing more than one process at a time. In that
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case, inferior_ptid will contain the main process ID and the
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individual thread (process) ID. get_thread_id () is used to get
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the thread id if it's available, and the process id otherwise. */
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static int
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get_thread_id (ptid_t ptid)
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{
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int tid = ptid_get_lwp (ptid);
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if (0 == tid)
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tid = ptid_get_pid (ptid);
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return tid;
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}
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/* Macro definitions, data structures, and code for the hardware
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breakpoint and hardware watchpoint support follow. We use the
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following abbreviations throughout the code:
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hw - hardware
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bp - breakpoint
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wp - watchpoint */
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/* Maximum number of hardware breakpoint and watchpoint registers.
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Neither of these values may exceed the width of dr_changed_t
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measured in bits. */
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#define AARCH64_HBP_MAX_NUM 16
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#define AARCH64_HWP_MAX_NUM 16
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/* Alignment requirement in bytes for addresses written to
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hardware breakpoint and watchpoint value registers.
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A ptrace call attempting to set an address that does not meet the
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alignment criteria will fail. Limited support has been provided in
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this port for unaligned watchpoints, such that from a GDB user
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perspective, an unaligned watchpoint may be requested.
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This is achieved by minimally enlarging the watched area to meet the
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alignment requirement, and if necessary, splitting the watchpoint
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over several hardware watchpoint registers. */
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#define AARCH64_HBP_ALIGNMENT 4
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#define AARCH64_HWP_ALIGNMENT 8
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/* The maximum length of a memory region that can be watched by one
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hardware watchpoint register. */
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#define AARCH64_HWP_MAX_LEN_PER_REG 8
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/* ptrace hardware breakpoint resource info is formatted as follows:
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31 24 16 8 0
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+---------------+--------------+---------------+---------------+
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| RESERVED | RESERVED | DEBUG_ARCH | NUM_SLOTS |
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+---------------+--------------+---------------+---------------+ */
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/* Macros to extract fields from the hardware debug information word. */
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#define AARCH64_DEBUG_NUM_SLOTS(x) ((x) & 0xff)
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#define AARCH64_DEBUG_ARCH(x) (((x) >> 8) & 0xff)
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/* Macro for the expected version of the ARMv8-A debug architecture. */
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#define AARCH64_DEBUG_ARCH_V8 0x6
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/* Number of hardware breakpoints/watchpoints the target supports.
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They are initialized with values obtained via the ptrace calls
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with NT_ARM_HW_BREAK and NT_ARM_HW_WATCH respectively. */
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static int aarch64_num_bp_regs;
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static int aarch64_num_wp_regs;
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/* Each bit of a variable of this type is used to indicate whether a
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hardware breakpoint or watchpoint setting has been changed since
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the last update.
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Bit N corresponds to the Nth hardware breakpoint or watchpoint
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setting which is managed in aarch64_debug_reg_state, where N is
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valid between 0 and the total number of the hardware breakpoint or
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watchpoint debug registers minus 1.
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When bit N is 1, the corresponding breakpoint or watchpoint setting
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has changed, and therefore the corresponding hardware debug
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register needs to be updated via the ptrace interface.
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In the per-thread arch-specific data area, we define two such
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variables for per-thread hardware breakpoint and watchpoint
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settings respectively.
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This type is part of the mechanism which helps reduce the number of
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ptrace calls to the kernel, i.e. avoid asking the kernel to write
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to the debug registers with unchanged values. */
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typedef ULONGEST dr_changed_t;
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/* Set each of the lower M bits of X to 1; assert X is wide enough. */
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#define DR_MARK_ALL_CHANGED(x, m) \
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do \
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{ \
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gdb_assert (sizeof ((x)) * 8 >= (m)); \
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(x) = (((dr_changed_t)1 << (m)) - 1); \
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} while (0)
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#define DR_MARK_N_CHANGED(x, n) \
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do \
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{ \
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(x) |= ((dr_changed_t)1 << (n)); \
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} while (0)
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#define DR_CLEAR_CHANGED(x) \
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do \
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{ \
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(x) = 0; \
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} while (0)
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#define DR_HAS_CHANGED(x) ((x) != 0)
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#define DR_N_HAS_CHANGED(x, n) ((x) & ((dr_changed_t)1 << (n)))
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/* Structure for managing the hardware breakpoint/watchpoint resources.
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DR_ADDR_* stores the address, DR_CTRL_* stores the control register
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content, and DR_REF_COUNT_* counts the numbers of references to the
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corresponding bp/wp, by which way the limited hardware resources
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are not wasted on duplicated bp/wp settings (though so far gdb has
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done a good job by not sending duplicated bp/wp requests). */
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struct aarch64_debug_reg_state
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{
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/* hardware breakpoint */
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CORE_ADDR dr_addr_bp[AARCH64_HBP_MAX_NUM];
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unsigned int dr_ctrl_bp[AARCH64_HBP_MAX_NUM];
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unsigned int dr_ref_count_bp[AARCH64_HBP_MAX_NUM];
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/* hardware watchpoint */
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CORE_ADDR dr_addr_wp[AARCH64_HWP_MAX_NUM];
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unsigned int dr_ctrl_wp[AARCH64_HWP_MAX_NUM];
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unsigned int dr_ref_count_wp[AARCH64_HWP_MAX_NUM];
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};
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/* Per-process data. We don't bind this to a per-inferior registry
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because of targets like x86 GNU/Linux that need to keep track of
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processes that aren't bound to any inferior (e.g., fork children,
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checkpoints). */
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struct aarch64_process_info
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{
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/* Linked list. */
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struct aarch64_process_info *next;
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/* The process identifier. */
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pid_t pid;
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/* Copy of aarch64 hardware debug registers. */
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struct aarch64_debug_reg_state state;
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};
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static struct aarch64_process_info *aarch64_process_list = NULL;
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/* Find process data for process PID. */
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static struct aarch64_process_info *
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aarch64_find_process_pid (pid_t pid)
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{
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struct aarch64_process_info *proc;
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for (proc = aarch64_process_list; proc; proc = proc->next)
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if (proc->pid == pid)
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return proc;
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return NULL;
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}
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/* Add process data for process PID. Returns newly allocated info
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object. */
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static struct aarch64_process_info *
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aarch64_add_process (pid_t pid)
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{
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struct aarch64_process_info *proc;
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proc = xcalloc (1, sizeof (*proc));
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proc->pid = pid;
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proc->next = aarch64_process_list;
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aarch64_process_list = proc;
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return proc;
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}
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/* Get data specific info for process PID, creating it if necessary.
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Never returns NULL. */
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static struct aarch64_process_info *
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aarch64_process_info_get (pid_t pid)
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{
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struct aarch64_process_info *proc;
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proc = aarch64_find_process_pid (pid);
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if (proc == NULL)
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proc = aarch64_add_process (pid);
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return proc;
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}
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/* Called whenever GDB is no longer debugging process PID. It deletes
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data structures that keep track of debug register state. */
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static void
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aarch64_forget_process (pid_t pid)
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{
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struct aarch64_process_info *proc, **proc_link;
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proc = aarch64_process_list;
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proc_link = &aarch64_process_list;
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while (proc != NULL)
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{
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if (proc->pid == pid)
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{
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*proc_link = proc->next;
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xfree (proc);
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return;
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}
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proc_link = &proc->next;
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proc = *proc_link;
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}
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}
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/* Get debug registers state for process PID. */
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static struct aarch64_debug_reg_state *
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aarch64_get_debug_reg_state (pid_t pid)
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{
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return &aarch64_process_info_get (pid)->state;
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}
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/* Per-thread arch-specific data we want to keep. */
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struct arch_lwp_info
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{
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/* When bit N is 1, it indicates the Nth hardware breakpoint or
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watchpoint register pair needs to be updated when the thread is
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resumed; see aarch64_linux_prepare_to_resume. */
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dr_changed_t dr_changed_bp;
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dr_changed_t dr_changed_wp;
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};
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/* Call ptrace to set the thread TID's hardware breakpoint/watchpoint
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registers with data from *STATE. */
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static void
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aarch64_linux_set_debug_regs (const struct aarch64_debug_reg_state *state,
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int tid, int watchpoint)
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{
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int i, count;
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struct iovec iov;
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struct user_hwdebug_state regs;
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const CORE_ADDR *addr;
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const unsigned int *ctrl;
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memset (®s, 0, sizeof (regs));
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iov.iov_base = ®s;
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count = watchpoint ? aarch64_num_wp_regs : aarch64_num_bp_regs;
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addr = watchpoint ? state->dr_addr_wp : state->dr_addr_bp;
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ctrl = watchpoint ? state->dr_ctrl_wp : state->dr_ctrl_bp;
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if (count == 0)
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return;
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iov.iov_len = (offsetof (struct user_hwdebug_state, dbg_regs[count - 1])
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+ sizeof (regs.dbg_regs [count - 1]));
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for (i = 0; i < count; i++)
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{
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regs.dbg_regs[i].addr = addr[i];
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regs.dbg_regs[i].ctrl = ctrl[i];
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}
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if (ptrace (PTRACE_SETREGSET, tid,
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watchpoint ? NT_ARM_HW_WATCH : NT_ARM_HW_BREAK,
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(void *) &iov))
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error (_("Unexpected error setting hardware debug registers"));
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}
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struct aarch64_dr_update_callback_param
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{
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int is_watchpoint;
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unsigned int idx;
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};
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/* Callback for iterate_over_lwps. Records the
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information about the change of one hardware breakpoint/watchpoint
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setting for the thread LWP.
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The information is passed in via PTR.
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N.B. The actual updating of hardware debug registers is not
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carried out until the moment the thread is resumed. */
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static int
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debug_reg_change_callback (struct lwp_info *lwp, void *ptr)
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{
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struct aarch64_dr_update_callback_param *param_p
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= (struct aarch64_dr_update_callback_param *) ptr;
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int pid = get_thread_id (lwp->ptid);
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int idx = param_p->idx;
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int is_watchpoint = param_p->is_watchpoint;
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struct arch_lwp_info *info = lwp->arch_private;
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dr_changed_t *dr_changed_ptr;
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dr_changed_t dr_changed;
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if (info == NULL)
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info = lwp->arch_private = XCNEW (struct arch_lwp_info);
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if (show_debug_regs)
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{
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fprintf_unfiltered (gdb_stdlog,
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"debug_reg_change_callback: \n\tOn entry:\n");
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fprintf_unfiltered (gdb_stdlog,
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"\tpid%d, dr_changed_bp=0x%s, "
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"dr_changed_wp=0x%s\n",
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pid, phex (info->dr_changed_bp, 8),
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phex (info->dr_changed_wp, 8));
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}
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dr_changed_ptr = is_watchpoint ? &info->dr_changed_wp
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: &info->dr_changed_bp;
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dr_changed = *dr_changed_ptr;
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gdb_assert (idx >= 0
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&& (idx <= (is_watchpoint ? aarch64_num_wp_regs
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: aarch64_num_bp_regs)));
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/* The actual update is done later just before resuming the lwp,
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we just mark that one register pair needs updating. */
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DR_MARK_N_CHANGED (dr_changed, idx);
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*dr_changed_ptr = dr_changed;
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/* If the lwp isn't stopped, force it to momentarily pause, so
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we can update its debug registers. */
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if (!lwp->stopped)
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linux_stop_lwp (lwp);
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if (show_debug_regs)
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{
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fprintf_unfiltered (gdb_stdlog,
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"\tOn exit:\n\tpid%d, dr_changed_bp=0x%s, "
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"dr_changed_wp=0x%s\n",
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pid, phex (info->dr_changed_bp, 8),
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phex (info->dr_changed_wp, 8));
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}
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/* Continue the iteration. */
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return 0;
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}
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/* Notify each thread that their IDXth breakpoint/watchpoint register
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pair needs to be updated. The message will be recorded in each
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thread's arch-specific data area, the actual updating will be done
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when the thread is resumed. */
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static void
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aarch64_notify_debug_reg_change (const struct aarch64_debug_reg_state *state,
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int is_watchpoint, unsigned int idx)
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{
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struct aarch64_dr_update_callback_param param;
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ptid_t pid_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
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param.is_watchpoint = is_watchpoint;
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param.idx = idx;
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iterate_over_lwps (pid_ptid, debug_reg_change_callback, (void *) ¶m);
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}
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/* Print the values of the cached breakpoint/watchpoint registers. */
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static void
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aarch64_show_debug_reg_state (struct aarch64_debug_reg_state *state,
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const char *func, CORE_ADDR addr,
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int len, int type)
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{
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int i;
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fprintf_unfiltered (gdb_stdlog, "%s", func);
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if (addr || len)
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fprintf_unfiltered (gdb_stdlog, " (addr=0x%08lx, len=%d, type=%s)",
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(unsigned long) addr, len,
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type == hw_write ? "hw-write-watchpoint"
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: (type == hw_read ? "hw-read-watchpoint"
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: (type == hw_access ? "hw-access-watchpoint"
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: (type == hw_execute ? "hw-breakpoint"
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: "??unknown??"))));
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fprintf_unfiltered (gdb_stdlog, ":\n");
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fprintf_unfiltered (gdb_stdlog, "\tBREAKPOINTs:\n");
|
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for (i = 0; i < aarch64_num_bp_regs; i++)
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fprintf_unfiltered (gdb_stdlog,
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"\tBP%d: addr=0x%08lx, ctrl=0x%08x, ref.count=%d\n",
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i, state->dr_addr_bp[i],
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state->dr_ctrl_bp[i], state->dr_ref_count_bp[i]);
|
||
|
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fprintf_unfiltered (gdb_stdlog, "\tWATCHPOINTs:\n");
|
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for (i = 0; i < aarch64_num_wp_regs; i++)
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fprintf_unfiltered (gdb_stdlog,
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"\tWP%d: addr=0x%08lx, ctrl=0x%08x, ref.count=%d\n",
|
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i, state->dr_addr_wp[i],
|
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state->dr_ctrl_wp[i], state->dr_ref_count_wp[i]);
|
||
}
|
||
|
||
/* Fill GDB's register array with the general-purpose register values
|
||
from the current thread. */
|
||
|
||
static void
|
||
fetch_gregs_from_thread (struct regcache *regcache)
|
||
{
|
||
int ret, regno, tid;
|
||
elf_gregset_t regs;
|
||
struct iovec iovec;
|
||
|
||
tid = get_thread_id (inferior_ptid);
|
||
|
||
iovec.iov_base = ®s;
|
||
iovec.iov_len = sizeof (regs);
|
||
|
||
ret = ptrace (PTRACE_GETREGSET, tid, NT_PRSTATUS, &iovec);
|
||
if (ret < 0)
|
||
perror_with_name (_("Unable to fetch general registers."));
|
||
|
||
for (regno = AARCH64_X0_REGNUM; regno <= AARCH64_CPSR_REGNUM; regno++)
|
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regcache_raw_supply (regcache, regno,
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(char *) ®s[regno - AARCH64_X0_REGNUM]);
|
||
}
|
||
|
||
/* Store to the current thread the valid general-purpose register
|
||
values in the GDB's register array. */
|
||
|
||
static void
|
||
store_gregs_to_thread (const struct regcache *regcache)
|
||
{
|
||
int ret, regno, tid;
|
||
elf_gregset_t regs;
|
||
struct iovec iovec;
|
||
|
||
tid = get_thread_id (inferior_ptid);
|
||
|
||
iovec.iov_base = ®s;
|
||
iovec.iov_len = sizeof (regs);
|
||
|
||
ret = ptrace (PTRACE_GETREGSET, tid, NT_PRSTATUS, &iovec);
|
||
if (ret < 0)
|
||
perror_with_name (_("Unable to fetch general registers."));
|
||
|
||
for (regno = AARCH64_X0_REGNUM; regno <= AARCH64_CPSR_REGNUM; regno++)
|
||
if (REG_VALID == regcache_register_status (regcache, regno))
|
||
regcache_raw_collect (regcache, regno,
|
||
(char *) ®s[regno - AARCH64_X0_REGNUM]);
|
||
|
||
ret = ptrace (PTRACE_SETREGSET, tid, NT_PRSTATUS, &iovec);
|
||
if (ret < 0)
|
||
perror_with_name (_("Unable to store general registers."));
|
||
}
|
||
|
||
/* Fill GDB's register array with the fp/simd register values
|
||
from the current thread. */
|
||
|
||
static void
|
||
fetch_fpregs_from_thread (struct regcache *regcache)
|
||
{
|
||
int ret, regno, tid;
|
||
elf_fpregset_t regs;
|
||
struct iovec iovec;
|
||
|
||
tid = get_thread_id (inferior_ptid);
|
||
|
||
iovec.iov_base = ®s;
|
||
iovec.iov_len = sizeof (regs);
|
||
|
||
ret = ptrace (PTRACE_GETREGSET, tid, NT_FPREGSET, &iovec);
|
||
if (ret < 0)
|
||
perror_with_name (_("Unable to fetch FP/SIMD registers."));
|
||
|
||
for (regno = AARCH64_V0_REGNUM; regno <= AARCH64_V31_REGNUM; regno++)
|
||
regcache_raw_supply (regcache, regno,
|
||
(char *) ®s.vregs[regno - AARCH64_V0_REGNUM]);
|
||
|
||
regcache_raw_supply (regcache, AARCH64_FPSR_REGNUM, (char *) ®s.fpsr);
|
||
regcache_raw_supply (regcache, AARCH64_FPCR_REGNUM, (char *) ®s.fpcr);
|
||
}
|
||
|
||
/* Store to the current thread the valid fp/simd register
|
||
values in the GDB's register array. */
|
||
|
||
static void
|
||
store_fpregs_to_thread (const struct regcache *regcache)
|
||
{
|
||
int ret, regno, tid;
|
||
elf_fpregset_t regs;
|
||
struct iovec iovec;
|
||
|
||
tid = get_thread_id (inferior_ptid);
|
||
|
||
iovec.iov_base = ®s;
|
||
iovec.iov_len = sizeof (regs);
|
||
|
||
ret = ptrace (PTRACE_GETREGSET, tid, NT_FPREGSET, &iovec);
|
||
if (ret < 0)
|
||
perror_with_name (_("Unable to fetch FP/SIMD registers."));
|
||
|
||
for (regno = AARCH64_V0_REGNUM; regno <= AARCH64_V31_REGNUM; regno++)
|
||
if (REG_VALID == regcache_register_status (regcache, regno))
|
||
regcache_raw_collect (regcache, regno,
|
||
(char *) ®s.vregs[regno - AARCH64_V0_REGNUM]);
|
||
|
||
if (REG_VALID == regcache_register_status (regcache, AARCH64_FPSR_REGNUM))
|
||
regcache_raw_collect (regcache, AARCH64_FPSR_REGNUM, (char *) ®s.fpsr);
|
||
if (REG_VALID == regcache_register_status (regcache, AARCH64_FPCR_REGNUM))
|
||
regcache_raw_collect (regcache, AARCH64_FPCR_REGNUM, (char *) ®s.fpcr);
|
||
|
||
ret = ptrace (PTRACE_SETREGSET, tid, NT_FPREGSET, &iovec);
|
||
if (ret < 0)
|
||
perror_with_name (_("Unable to store FP/SIMD registers."));
|
||
}
|
||
|
||
/* Implement the "to_fetch_register" target_ops method. */
|
||
|
||
static void
|
||
aarch64_linux_fetch_inferior_registers (struct target_ops *ops,
|
||
struct regcache *regcache,
|
||
int regno)
|
||
{
|
||
if (regno == -1)
|
||
{
|
||
fetch_gregs_from_thread (regcache);
|
||
fetch_fpregs_from_thread (regcache);
|
||
}
|
||
else if (regno < AARCH64_V0_REGNUM)
|
||
fetch_gregs_from_thread (regcache);
|
||
else
|
||
fetch_fpregs_from_thread (regcache);
|
||
}
|
||
|
||
/* Implement the "to_store_register" target_ops method. */
|
||
|
||
static void
|
||
aarch64_linux_store_inferior_registers (struct target_ops *ops,
|
||
struct regcache *regcache,
|
||
int regno)
|
||
{
|
||
if (regno == -1)
|
||
{
|
||
store_gregs_to_thread (regcache);
|
||
store_fpregs_to_thread (regcache);
|
||
}
|
||
else if (regno < AARCH64_V0_REGNUM)
|
||
store_gregs_to_thread (regcache);
|
||
else
|
||
store_fpregs_to_thread (regcache);
|
||
}
|
||
|
||
/* Fill register REGNO (if it is a general-purpose register) in
|
||
*GREGSETPS with the value in GDB's register array. If REGNO is -1,
|
||
do this for all registers. */
|
||
|
||
void
|
||
fill_gregset (const struct regcache *regcache,
|
||
gdb_gregset_t *gregsetp, int regno)
|
||
{
|
||
regcache_collect_regset (&aarch64_linux_gregset, regcache,
|
||
regno, (gdb_byte *) gregsetp,
|
||
AARCH64_LINUX_SIZEOF_GREGSET);
|
||
}
|
||
|
||
/* Fill GDB's register array with the general-purpose register values
|
||
in *GREGSETP. */
|
||
|
||
void
|
||
supply_gregset (struct regcache *regcache, const gdb_gregset_t *gregsetp)
|
||
{
|
||
regcache_supply_regset (&aarch64_linux_gregset, regcache, -1,
|
||
(const gdb_byte *) gregsetp,
|
||
AARCH64_LINUX_SIZEOF_GREGSET);
|
||
}
|
||
|
||
/* Fill register REGNO (if it is a floating-point register) in
|
||
*FPREGSETP with the value in GDB's register array. If REGNO is -1,
|
||
do this for all registers. */
|
||
|
||
void
|
||
fill_fpregset (const struct regcache *regcache,
|
||
gdb_fpregset_t *fpregsetp, int regno)
|
||
{
|
||
regcache_collect_regset (&aarch64_linux_fpregset, regcache,
|
||
regno, (gdb_byte *) fpregsetp,
|
||
AARCH64_LINUX_SIZEOF_FPREGSET);
|
||
}
|
||
|
||
/* Fill GDB's register array with the floating-point register values
|
||
in *FPREGSETP. */
|
||
|
||
void
|
||
supply_fpregset (struct regcache *regcache, const gdb_fpregset_t *fpregsetp)
|
||
{
|
||
regcache_supply_regset (&aarch64_linux_fpregset, regcache, -1,
|
||
(const gdb_byte *) fpregsetp,
|
||
AARCH64_LINUX_SIZEOF_FPREGSET);
|
||
}
|
||
|
||
/* Called when resuming a thread.
|
||
The hardware debug registers are updated when there is any change. */
|
||
|
||
static void
|
||
aarch64_linux_prepare_to_resume (struct lwp_info *lwp)
|
||
{
|
||
struct arch_lwp_info *info = lwp->arch_private;
|
||
|
||
/* NULL means this is the main thread still going through the shell,
|
||
or, no watchpoint has been set yet. In that case, there's
|
||
nothing to do. */
|
||
if (info == NULL)
|
||
return;
|
||
|
||
if (DR_HAS_CHANGED (info->dr_changed_bp)
|
||
|| DR_HAS_CHANGED (info->dr_changed_wp))
|
||
{
|
||
int tid = ptid_get_lwp (lwp->ptid);
|
||
struct aarch64_debug_reg_state *state
|
||
= aarch64_get_debug_reg_state (ptid_get_pid (lwp->ptid));
|
||
|
||
if (show_debug_regs)
|
||
fprintf_unfiltered (gdb_stdlog, "prepare_to_resume thread %d\n", tid);
|
||
|
||
/* Watchpoints. */
|
||
if (DR_HAS_CHANGED (info->dr_changed_wp))
|
||
{
|
||
aarch64_linux_set_debug_regs (state, tid, 1);
|
||
DR_CLEAR_CHANGED (info->dr_changed_wp);
|
||
}
|
||
|
||
/* Breakpoints. */
|
||
if (DR_HAS_CHANGED (info->dr_changed_bp))
|
||
{
|
||
aarch64_linux_set_debug_regs (state, tid, 0);
|
||
DR_CLEAR_CHANGED (info->dr_changed_bp);
|
||
}
|
||
}
|
||
}
|
||
|
||
static void
|
||
aarch64_linux_new_thread (struct lwp_info *lp)
|
||
{
|
||
struct arch_lwp_info *info = XCNEW (struct arch_lwp_info);
|
||
|
||
/* Mark that all the hardware breakpoint/watchpoint register pairs
|
||
for this thread need to be initialized. */
|
||
DR_MARK_ALL_CHANGED (info->dr_changed_bp, aarch64_num_bp_regs);
|
||
DR_MARK_ALL_CHANGED (info->dr_changed_wp, aarch64_num_wp_regs);
|
||
|
||
lp->arch_private = info;
|
||
}
|
||
|
||
/* linux_nat_new_fork hook. */
|
||
|
||
static void
|
||
aarch64_linux_new_fork (struct lwp_info *parent, pid_t child_pid)
|
||
{
|
||
pid_t parent_pid;
|
||
struct aarch64_debug_reg_state *parent_state;
|
||
struct aarch64_debug_reg_state *child_state;
|
||
|
||
/* NULL means no watchpoint has ever been set in the parent. In
|
||
that case, there's nothing to do. */
|
||
if (parent->arch_private == NULL)
|
||
return;
|
||
|
||
/* GDB core assumes the child inherits the watchpoints/hw
|
||
breakpoints of the parent, and will remove them all from the
|
||
forked off process. Copy the debug registers mirrors into the
|
||
new process so that all breakpoints and watchpoints can be
|
||
removed together. */
|
||
|
||
parent_pid = ptid_get_pid (parent->ptid);
|
||
parent_state = aarch64_get_debug_reg_state (parent_pid);
|
||
child_state = aarch64_get_debug_reg_state (child_pid);
|
||
*child_state = *parent_state;
|
||
}
|
||
|
||
|
||
/* Called by libthread_db. Returns a pointer to the thread local
|
||
storage (or its descriptor). */
|
||
|
||
ps_err_e
|
||
ps_get_thread_area (const struct ps_prochandle *ph,
|
||
lwpid_t lwpid, int idx, void **base)
|
||
{
|
||
struct iovec iovec;
|
||
uint64_t reg;
|
||
|
||
iovec.iov_base = ®
|
||
iovec.iov_len = sizeof (reg);
|
||
|
||
if (ptrace (PTRACE_GETREGSET, lwpid, NT_ARM_TLS, &iovec) != 0)
|
||
return PS_ERR;
|
||
|
||
/* IDX is the bias from the thread pointer to the beginning of the
|
||
thread descriptor. It has to be subtracted due to implementation
|
||
quirks in libthread_db. */
|
||
*base = (void *) (reg - idx);
|
||
|
||
return PS_OK;
|
||
}
|
||
|
||
|
||
/* Get the hardware debug register capacity information. */
|
||
|
||
static void
|
||
aarch64_linux_get_debug_reg_capacity (void)
|
||
{
|
||
int tid;
|
||
struct iovec iov;
|
||
struct user_hwdebug_state dreg_state;
|
||
|
||
tid = get_thread_id (inferior_ptid);
|
||
iov.iov_base = &dreg_state;
|
||
iov.iov_len = sizeof (dreg_state);
|
||
|
||
/* Get hardware watchpoint register info. */
|
||
if (ptrace (PTRACE_GETREGSET, tid, NT_ARM_HW_WATCH, &iov) == 0
|
||
&& AARCH64_DEBUG_ARCH (dreg_state.dbg_info) == AARCH64_DEBUG_ARCH_V8)
|
||
{
|
||
aarch64_num_wp_regs = AARCH64_DEBUG_NUM_SLOTS (dreg_state.dbg_info);
|
||
if (aarch64_num_wp_regs > AARCH64_HWP_MAX_NUM)
|
||
{
|
||
warning (_("Unexpected number of hardware watchpoint registers"
|
||
" reported by ptrace, got %d, expected %d."),
|
||
aarch64_num_wp_regs, AARCH64_HWP_MAX_NUM);
|
||
aarch64_num_wp_regs = AARCH64_HWP_MAX_NUM;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
warning (_("Unable to determine the number of hardware watchpoints"
|
||
" available."));
|
||
aarch64_num_wp_regs = 0;
|
||
}
|
||
|
||
/* Get hardware breakpoint register info. */
|
||
if (ptrace (PTRACE_GETREGSET, tid, NT_ARM_HW_BREAK, &iov) == 0
|
||
&& AARCH64_DEBUG_ARCH (dreg_state.dbg_info) == AARCH64_DEBUG_ARCH_V8)
|
||
{
|
||
aarch64_num_bp_regs = AARCH64_DEBUG_NUM_SLOTS (dreg_state.dbg_info);
|
||
if (aarch64_num_bp_regs > AARCH64_HBP_MAX_NUM)
|
||
{
|
||
warning (_("Unexpected number of hardware breakpoint registers"
|
||
" reported by ptrace, got %d, expected %d."),
|
||
aarch64_num_bp_regs, AARCH64_HBP_MAX_NUM);
|
||
aarch64_num_bp_regs = AARCH64_HBP_MAX_NUM;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
warning (_("Unable to determine the number of hardware breakpoints"
|
||
" available."));
|
||
aarch64_num_bp_regs = 0;
|
||
}
|
||
}
|
||
|
||
static void (*super_post_startup_inferior) (struct target_ops *self,
|
||
ptid_t ptid);
|
||
|
||
/* Implement the "to_post_startup_inferior" target_ops method. */
|
||
|
||
static void
|
||
aarch64_linux_child_post_startup_inferior (struct target_ops *self,
|
||
ptid_t ptid)
|
||
{
|
||
aarch64_forget_process (ptid_get_pid (ptid));
|
||
aarch64_linux_get_debug_reg_capacity ();
|
||
super_post_startup_inferior (self, ptid);
|
||
}
|
||
|
||
/* Implement the "to_read_description" target_ops method. */
|
||
|
||
static const struct target_desc *
|
||
aarch64_linux_read_description (struct target_ops *ops)
|
||
{
|
||
return tdesc_aarch64;
|
||
}
|
||
|
||
/* Given the (potentially unaligned) watchpoint address in ADDR and
|
||
length in LEN, return the aligned address and aligned length in
|
||
*ALIGNED_ADDR_P and *ALIGNED_LEN_P, respectively. The returned
|
||
aligned address and length will be valid values to write to the
|
||
hardware watchpoint value and control registers.
|
||
|
||
The given watchpoint may get truncated if more than one hardware
|
||
register is needed to cover the watched region. *NEXT_ADDR_P
|
||
and *NEXT_LEN_P, if non-NULL, will return the address and length
|
||
of the remaining part of the watchpoint (which can be processed
|
||
by calling this routine again to generate another aligned address
|
||
and length pair.
|
||
|
||
See the comment above the function of the same name in
|
||
gdbserver/linux-aarch64-low.c for more information. */
|
||
|
||
static void
|
||
aarch64_align_watchpoint (CORE_ADDR addr, int len, CORE_ADDR *aligned_addr_p,
|
||
int *aligned_len_p, CORE_ADDR *next_addr_p,
|
||
int *next_len_p)
|
||
{
|
||
int aligned_len;
|
||
unsigned int offset;
|
||
CORE_ADDR aligned_addr;
|
||
const unsigned int alignment = AARCH64_HWP_ALIGNMENT;
|
||
const unsigned int max_wp_len = AARCH64_HWP_MAX_LEN_PER_REG;
|
||
|
||
/* As assumed by the algorithm. */
|
||
gdb_assert (alignment == max_wp_len);
|
||
|
||
if (len <= 0)
|
||
return;
|
||
|
||
/* Address to be put into the hardware watchpoint value register
|
||
must be aligned. */
|
||
offset = addr & (alignment - 1);
|
||
aligned_addr = addr - offset;
|
||
|
||
gdb_assert (offset >= 0 && offset < alignment);
|
||
gdb_assert (aligned_addr >= 0 && aligned_addr <= addr);
|
||
gdb_assert (offset + len > 0);
|
||
|
||
if (offset + len >= max_wp_len)
|
||
{
|
||
/* Need more than one watchpoint registers; truncate it at the
|
||
alignment boundary. */
|
||
aligned_len = max_wp_len;
|
||
len -= (max_wp_len - offset);
|
||
addr += (max_wp_len - offset);
|
||
gdb_assert ((addr & (alignment - 1)) == 0);
|
||
}
|
||
else
|
||
{
|
||
/* Find the smallest valid length that is large enough to
|
||
accommodate this watchpoint. */
|
||
static const unsigned char
|
||
aligned_len_array[AARCH64_HWP_MAX_LEN_PER_REG] =
|
||
{ 1, 2, 4, 4, 8, 8, 8, 8 };
|
||
|
||
aligned_len = aligned_len_array[offset + len - 1];
|
||
addr += len;
|
||
len = 0;
|
||
}
|
||
|
||
if (aligned_addr_p)
|
||
*aligned_addr_p = aligned_addr;
|
||
if (aligned_len_p)
|
||
*aligned_len_p = aligned_len;
|
||
if (next_addr_p)
|
||
*next_addr_p = addr;
|
||
if (next_len_p)
|
||
*next_len_p = len;
|
||
}
|
||
|
||
/* Returns the number of hardware watchpoints of type TYPE that we can
|
||
set. Value is positive if we can set CNT watchpoints, zero if
|
||
setting watchpoints of type TYPE is not supported, and negative if
|
||
CNT is more than the maximum number of watchpoints of type TYPE
|
||
that we can support. TYPE is one of bp_hardware_watchpoint,
|
||
bp_read_watchpoint, bp_write_watchpoint, or bp_hardware_breakpoint.
|
||
CNT is the number of such watchpoints used so far (including this
|
||
one). OTHERTYPE is non-zero if other types of watchpoints are
|
||
currently enabled.
|
||
|
||
We always return 1 here because we don't have enough information
|
||
about possible overlap of addresses that they want to watch. As an
|
||
extreme example, consider the case where all the watchpoints watch
|
||
the same address and the same region length: then we can handle a
|
||
virtually unlimited number of watchpoints, due to debug register
|
||
sharing implemented via reference counts. */
|
||
|
||
static int
|
||
aarch64_linux_can_use_hw_breakpoint (struct target_ops *self,
|
||
int type, int cnt, int othertype)
|
||
{
|
||
return 1;
|
||
}
|
||
|
||
/* ptrace expects control registers to be formatted as follows:
|
||
|
||
31 13 5 3 1 0
|
||
+--------------------------------+----------+------+------+----+
|
||
| RESERVED (SBZ) | LENGTH | TYPE | PRIV | EN |
|
||
+--------------------------------+----------+------+------+----+
|
||
|
||
The TYPE field is ignored for breakpoints. */
|
||
|
||
#define DR_CONTROL_ENABLED(ctrl) (((ctrl) & 0x1) == 1)
|
||
#define DR_CONTROL_LENGTH(ctrl) (((ctrl) >> 5) & 0xff)
|
||
|
||
/* Utility function that returns the length in bytes of a watchpoint
|
||
according to the content of a hardware debug control register CTRL.
|
||
Note that the kernel currently only supports the following Byte
|
||
Address Select (BAS) values: 0x1, 0x3, 0xf and 0xff, which means
|
||
that for a hardware watchpoint, its valid length can only be 1
|
||
byte, 2 bytes, 4 bytes or 8 bytes. */
|
||
|
||
static inline unsigned int
|
||
aarch64_watchpoint_length (unsigned int ctrl)
|
||
{
|
||
switch (DR_CONTROL_LENGTH (ctrl))
|
||
{
|
||
case 0x01:
|
||
return 1;
|
||
case 0x03:
|
||
return 2;
|
||
case 0x0f:
|
||
return 4;
|
||
case 0xff:
|
||
return 8;
|
||
default:
|
||
return 0;
|
||
}
|
||
}
|
||
|
||
/* Given the hardware breakpoint or watchpoint type TYPE and its
|
||
length LEN, return the expected encoding for a hardware
|
||
breakpoint/watchpoint control register. */
|
||
|
||
static unsigned int
|
||
aarch64_point_encode_ctrl_reg (int type, int len)
|
||
{
|
||
unsigned int ctrl, ttype;
|
||
|
||
/* type */
|
||
switch (type)
|
||
{
|
||
case hw_write:
|
||
ttype = 2;
|
||
break;
|
||
case hw_read:
|
||
ttype = 1;
|
||
break;
|
||
case hw_access:
|
||
ttype = 3;
|
||
break;
|
||
case hw_execute:
|
||
ttype = 0;
|
||
break;
|
||
default:
|
||
perror_with_name (_("Unrecognized breakpoint/watchpoint type"));
|
||
}
|
||
ctrl = ttype << 3;
|
||
|
||
/* length bitmask */
|
||
ctrl |= ((1 << len) - 1) << 5;
|
||
/* enabled at el0 */
|
||
ctrl |= (2 << 1) | 1;
|
||
|
||
return ctrl;
|
||
}
|
||
|
||
/* Addresses to be written to the hardware breakpoint and watchpoint
|
||
value registers need to be aligned; the alignment is 4-byte and
|
||
8-type respectively. Linux kernel rejects any non-aligned address
|
||
it receives from the related ptrace call. Furthermore, the kernel
|
||
currently only supports the following Byte Address Select (BAS)
|
||
values: 0x1, 0x3, 0xf and 0xff, which means that for a hardware
|
||
watchpoint to be accepted by the kernel (via ptrace call), its
|
||
valid length can only be 1 byte, 2 bytes, 4 bytes or 8 bytes.
|
||
Despite these limitations, the unaligned watchpoint is supported in
|
||
this port.
|
||
|
||
Return 0 for any non-compliant ADDR and/or LEN; return 1 otherwise. */
|
||
|
||
static int
|
||
aarch64_point_is_aligned (int is_watchpoint, CORE_ADDR addr, int len)
|
||
{
|
||
unsigned int alignment = is_watchpoint ? AARCH64_HWP_ALIGNMENT
|
||
: AARCH64_HBP_ALIGNMENT;
|
||
|
||
if (addr & (alignment - 1))
|
||
return 0;
|
||
|
||
if (len != 8 && len != 4 && len != 2 && len != 1)
|
||
return 0;
|
||
|
||
return 1;
|
||
}
|
||
|
||
/* Record the insertion of one breakpoint/watchpoint, as represented
|
||
by ADDR and CTRL, in the cached debug register state area *STATE. */
|
||
|
||
static int
|
||
aarch64_dr_state_insert_one_point (struct aarch64_debug_reg_state *state,
|
||
int type, CORE_ADDR addr, int len)
|
||
{
|
||
int i, idx, num_regs, is_watchpoint;
|
||
unsigned int ctrl, *dr_ctrl_p, *dr_ref_count;
|
||
CORE_ADDR *dr_addr_p;
|
||
|
||
/* Set up state pointers. */
|
||
is_watchpoint = (type != hw_execute);
|
||
gdb_assert (aarch64_point_is_aligned (is_watchpoint, addr, len));
|
||
if (is_watchpoint)
|
||
{
|
||
num_regs = aarch64_num_wp_regs;
|
||
dr_addr_p = state->dr_addr_wp;
|
||
dr_ctrl_p = state->dr_ctrl_wp;
|
||
dr_ref_count = state->dr_ref_count_wp;
|
||
}
|
||
else
|
||
{
|
||
num_regs = aarch64_num_bp_regs;
|
||
dr_addr_p = state->dr_addr_bp;
|
||
dr_ctrl_p = state->dr_ctrl_bp;
|
||
dr_ref_count = state->dr_ref_count_bp;
|
||
}
|
||
|
||
ctrl = aarch64_point_encode_ctrl_reg (type, len);
|
||
|
||
/* Find an existing or free register in our cache. */
|
||
idx = -1;
|
||
for (i = 0; i < num_regs; ++i)
|
||
{
|
||
if ((dr_ctrl_p[i] & 1) == 0)
|
||
{
|
||
gdb_assert (dr_ref_count[i] == 0);
|
||
idx = i;
|
||
/* no break; continue hunting for an existing one. */
|
||
}
|
||
else if (dr_addr_p[i] == addr && dr_ctrl_p[i] == ctrl)
|
||
{
|
||
gdb_assert (dr_ref_count[i] != 0);
|
||
idx = i;
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* No space. */
|
||
if (idx == -1)
|
||
return -1;
|
||
|
||
/* Update our cache. */
|
||
if ((dr_ctrl_p[idx] & 1) == 0)
|
||
{
|
||
/* new entry */
|
||
dr_addr_p[idx] = addr;
|
||
dr_ctrl_p[idx] = ctrl;
|
||
dr_ref_count[idx] = 1;
|
||
/* Notify the change. */
|
||
aarch64_notify_debug_reg_change (state, is_watchpoint, idx);
|
||
}
|
||
else
|
||
{
|
||
/* existing entry */
|
||
dr_ref_count[idx]++;
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Record the removal of one breakpoint/watchpoint, as represented by
|
||
ADDR and CTRL, in the cached debug register state area *STATE. */
|
||
|
||
static int
|
||
aarch64_dr_state_remove_one_point (struct aarch64_debug_reg_state *state,
|
||
int type, CORE_ADDR addr, int len)
|
||
{
|
||
int i, num_regs, is_watchpoint;
|
||
unsigned int ctrl, *dr_ctrl_p, *dr_ref_count;
|
||
CORE_ADDR *dr_addr_p;
|
||
|
||
/* Set up state pointers. */
|
||
is_watchpoint = (type != hw_execute);
|
||
gdb_assert (aarch64_point_is_aligned (is_watchpoint, addr, len));
|
||
if (is_watchpoint)
|
||
{
|
||
num_regs = aarch64_num_wp_regs;
|
||
dr_addr_p = state->dr_addr_wp;
|
||
dr_ctrl_p = state->dr_ctrl_wp;
|
||
dr_ref_count = state->dr_ref_count_wp;
|
||
}
|
||
else
|
||
{
|
||
num_regs = aarch64_num_bp_regs;
|
||
dr_addr_p = state->dr_addr_bp;
|
||
dr_ctrl_p = state->dr_ctrl_bp;
|
||
dr_ref_count = state->dr_ref_count_bp;
|
||
}
|
||
|
||
ctrl = aarch64_point_encode_ctrl_reg (type, len);
|
||
|
||
/* Find the entry that matches the ADDR and CTRL. */
|
||
for (i = 0; i < num_regs; ++i)
|
||
if (dr_addr_p[i] == addr && dr_ctrl_p[i] == ctrl)
|
||
{
|
||
gdb_assert (dr_ref_count[i] != 0);
|
||
break;
|
||
}
|
||
|
||
/* Not found. */
|
||
if (i == num_regs)
|
||
return -1;
|
||
|
||
/* Clear our cache. */
|
||
if (--dr_ref_count[i] == 0)
|
||
{
|
||
/* Clear the enable bit. */
|
||
ctrl &= ~1;
|
||
dr_addr_p[i] = 0;
|
||
dr_ctrl_p[i] = ctrl;
|
||
/* Notify the change. */
|
||
aarch64_notify_debug_reg_change (state, is_watchpoint, i);
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Implement insertion and removal of a single breakpoint. */
|
||
|
||
static int
|
||
aarch64_handle_breakpoint (int type, CORE_ADDR addr, int len, int is_insert)
|
||
{
|
||
struct aarch64_debug_reg_state *state;
|
||
|
||
/* The hardware breakpoint on AArch64 should always be 4-byte
|
||
aligned. */
|
||
if (!aarch64_point_is_aligned (0 /* is_watchpoint */ , addr, len))
|
||
return -1;
|
||
|
||
state = aarch64_get_debug_reg_state (ptid_get_pid (inferior_ptid));
|
||
|
||
if (is_insert)
|
||
return aarch64_dr_state_insert_one_point (state, type, addr, len);
|
||
else
|
||
return aarch64_dr_state_remove_one_point (state, type, addr, len);
|
||
}
|
||
|
||
/* Insert a hardware-assisted breakpoint at BP_TGT->reqstd_address.
|
||
Return 0 on success, -1 on failure. */
|
||
|
||
static int
|
||
aarch64_linux_insert_hw_breakpoint (struct target_ops *self,
|
||
struct gdbarch *gdbarch,
|
||
struct bp_target_info *bp_tgt)
|
||
{
|
||
int ret;
|
||
CORE_ADDR addr = bp_tgt->placed_address = bp_tgt->reqstd_address;
|
||
const int len = 4;
|
||
const int type = hw_execute;
|
||
|
||
if (show_debug_regs)
|
||
fprintf_unfiltered
|
||
(gdb_stdlog,
|
||
"insert_hw_breakpoint on entry (addr=0x%08lx, len=%d))\n",
|
||
(unsigned long) addr, len);
|
||
|
||
ret = aarch64_handle_breakpoint (type, addr, len, 1 /* is_insert */);
|
||
|
||
if (show_debug_regs)
|
||
{
|
||
struct aarch64_debug_reg_state *state
|
||
= aarch64_get_debug_reg_state (ptid_get_pid (inferior_ptid));
|
||
|
||
aarch64_show_debug_reg_state (state,
|
||
"insert_hw_watchpoint", addr, len, type);
|
||
}
|
||
|
||
return ret;
|
||
}
|
||
|
||
/* Remove a hardware-assisted breakpoint at BP_TGT->placed_address.
|
||
Return 0 on success, -1 on failure. */
|
||
|
||
static int
|
||
aarch64_linux_remove_hw_breakpoint (struct target_ops *self,
|
||
struct gdbarch *gdbarch,
|
||
struct bp_target_info *bp_tgt)
|
||
{
|
||
int ret;
|
||
CORE_ADDR addr = bp_tgt->placed_address;
|
||
const int len = 4;
|
||
const int type = hw_execute;
|
||
|
||
if (show_debug_regs)
|
||
fprintf_unfiltered
|
||
(gdb_stdlog, "remove_hw_breakpoint on entry (addr=0x%08lx, len=%d))\n",
|
||
(unsigned long) addr, len);
|
||
|
||
ret = aarch64_handle_breakpoint (type, addr, len, 0 /* is_insert */);
|
||
|
||
if (show_debug_regs)
|
||
{
|
||
struct aarch64_debug_reg_state *state
|
||
= aarch64_get_debug_reg_state (ptid_get_pid (inferior_ptid));
|
||
|
||
aarch64_show_debug_reg_state (state,
|
||
"remove_hw_watchpoint", addr, len, type);
|
||
}
|
||
|
||
return ret;
|
||
}
|
||
|
||
/* This is essentially the same as aarch64_handle_breakpoint, apart
|
||
from that it is an aligned watchpoint to be handled. */
|
||
|
||
static int
|
||
aarch64_handle_aligned_watchpoint (int type, CORE_ADDR addr, int len,
|
||
int is_insert)
|
||
{
|
||
struct aarch64_debug_reg_state *state
|
||
= aarch64_get_debug_reg_state (ptid_get_pid (inferior_ptid));
|
||
|
||
if (is_insert)
|
||
return aarch64_dr_state_insert_one_point (state, type, addr, len);
|
||
else
|
||
return aarch64_dr_state_remove_one_point (state, type, addr, len);
|
||
}
|
||
|
||
/* Insert/remove unaligned watchpoint by calling
|
||
aarch64_align_watchpoint repeatedly until the whole watched region,
|
||
as represented by ADDR and LEN, has been properly aligned and ready
|
||
to be written to one or more hardware watchpoint registers.
|
||
IS_INSERT indicates whether this is an insertion or a deletion.
|
||
Return 0 if succeed. */
|
||
|
||
static int
|
||
aarch64_handle_unaligned_watchpoint (int type, CORE_ADDR addr, int len,
|
||
int is_insert)
|
||
{
|
||
struct aarch64_debug_reg_state *state
|
||
= aarch64_get_debug_reg_state (ptid_get_pid (inferior_ptid));
|
||
|
||
while (len > 0)
|
||
{
|
||
CORE_ADDR aligned_addr;
|
||
int aligned_len, ret;
|
||
|
||
aarch64_align_watchpoint (addr, len, &aligned_addr, &aligned_len,
|
||
&addr, &len);
|
||
|
||
if (is_insert)
|
||
ret = aarch64_dr_state_insert_one_point (state, type, aligned_addr,
|
||
aligned_len);
|
||
else
|
||
ret = aarch64_dr_state_remove_one_point (state, type, aligned_addr,
|
||
aligned_len);
|
||
|
||
if (show_debug_regs)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"handle_unaligned_watchpoint: is_insert: %d\n"
|
||
" aligned_addr: 0x%08lx, aligned_len: %d\n"
|
||
" next_addr: 0x%08lx, next_len: %d\n",
|
||
is_insert, aligned_addr, aligned_len, addr, len);
|
||
|
||
if (ret != 0)
|
||
return ret;
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Implements insertion and removal of a single watchpoint. */
|
||
|
||
static int
|
||
aarch64_handle_watchpoint (int type, CORE_ADDR addr, int len, int is_insert)
|
||
{
|
||
if (aarch64_point_is_aligned (1 /* is_watchpoint */ , addr, len))
|
||
return aarch64_handle_aligned_watchpoint (type, addr, len, is_insert);
|
||
else
|
||
return aarch64_handle_unaligned_watchpoint (type, addr, len, is_insert);
|
||
}
|
||
|
||
/* Implement the "to_insert_watchpoint" target_ops method.
|
||
|
||
Insert a watchpoint to watch a memory region which starts at
|
||
address ADDR and whose length is LEN bytes. Watch memory accesses
|
||
of the type TYPE. Return 0 on success, -1 on failure. */
|
||
|
||
static int
|
||
aarch64_linux_insert_watchpoint (struct target_ops *self,
|
||
CORE_ADDR addr, int len, int type,
|
||
struct expression *cond)
|
||
{
|
||
int ret;
|
||
|
||
if (show_debug_regs)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"insert_watchpoint on entry (addr=0x%08lx, len=%d)\n",
|
||
(unsigned long) addr, len);
|
||
|
||
gdb_assert (type != hw_execute);
|
||
|
||
ret = aarch64_handle_watchpoint (type, addr, len, 1 /* is_insert */);
|
||
|
||
if (show_debug_regs)
|
||
{
|
||
struct aarch64_debug_reg_state *state
|
||
= aarch64_get_debug_reg_state (ptid_get_pid (inferior_ptid));
|
||
|
||
aarch64_show_debug_reg_state (state,
|
||
"insert_watchpoint", addr, len, type);
|
||
}
|
||
|
||
return ret;
|
||
}
|
||
|
||
/* Implement the "to_remove_watchpoint" target_ops method.
|
||
Remove a watchpoint that watched the memory region which starts at
|
||
address ADDR, whose length is LEN bytes, and for accesses of the
|
||
type TYPE. Return 0 on success, -1 on failure. */
|
||
|
||
static int
|
||
aarch64_linux_remove_watchpoint (struct target_ops *self,
|
||
CORE_ADDR addr, int len, int type,
|
||
struct expression *cond)
|
||
{
|
||
int ret;
|
||
|
||
if (show_debug_regs)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"remove_watchpoint on entry (addr=0x%08lx, len=%d)\n",
|
||
(unsigned long) addr, len);
|
||
|
||
gdb_assert (type != hw_execute);
|
||
|
||
ret = aarch64_handle_watchpoint (type, addr, len, 0 /* is_insert */);
|
||
|
||
if (show_debug_regs)
|
||
{
|
||
struct aarch64_debug_reg_state *state
|
||
= aarch64_get_debug_reg_state (ptid_get_pid (inferior_ptid));
|
||
|
||
aarch64_show_debug_reg_state (state,
|
||
"remove_watchpoint", addr, len, type);
|
||
}
|
||
|
||
return ret;
|
||
}
|
||
|
||
/* Implement the "to_region_ok_for_hw_watchpoint" target_ops method. */
|
||
|
||
static int
|
||
aarch64_linux_region_ok_for_hw_watchpoint (struct target_ops *self,
|
||
CORE_ADDR addr, int len)
|
||
{
|
||
CORE_ADDR aligned_addr;
|
||
|
||
/* Can not set watchpoints for zero or negative lengths. */
|
||
if (len <= 0)
|
||
return 0;
|
||
|
||
/* Must have hardware watchpoint debug register(s). */
|
||
if (aarch64_num_wp_regs == 0)
|
||
return 0;
|
||
|
||
/* We support unaligned watchpoint address and arbitrary length,
|
||
as long as the size of the whole watched area after alignment
|
||
doesn't exceed size of the total area that all watchpoint debug
|
||
registers can watch cooperatively.
|
||
|
||
This is a very relaxed rule, but unfortunately there are
|
||
limitations, e.g. false-positive hits, due to limited support of
|
||
hardware debug registers in the kernel. See comment above
|
||
aarch64_align_watchpoint for more information. */
|
||
|
||
aligned_addr = addr & ~(AARCH64_HWP_MAX_LEN_PER_REG - 1);
|
||
if (aligned_addr + aarch64_num_wp_regs * AARCH64_HWP_MAX_LEN_PER_REG
|
||
< addr + len)
|
||
return 0;
|
||
|
||
/* All tests passed so we are likely to be able to set the watchpoint.
|
||
The reason that it is 'likely' rather than 'must' is because
|
||
we don't check the current usage of the watchpoint registers, and
|
||
there may not be enough registers available for this watchpoint.
|
||
Ideally we should check the cached debug register state, however
|
||
the checking is costly. */
|
||
return 1;
|
||
}
|
||
|
||
/* Implement the "to_stopped_data_address" target_ops method. */
|
||
|
||
static int
|
||
aarch64_linux_stopped_data_address (struct target_ops *target,
|
||
CORE_ADDR *addr_p)
|
||
{
|
||
siginfo_t siginfo;
|
||
int i, tid;
|
||
struct aarch64_debug_reg_state *state;
|
||
|
||
if (!linux_nat_get_siginfo (inferior_ptid, &siginfo))
|
||
return 0;
|
||
|
||
/* This must be a hardware breakpoint. */
|
||
if (siginfo.si_signo != SIGTRAP
|
||
|| (siginfo.si_code & 0xffff) != TRAP_HWBKPT)
|
||
return 0;
|
||
|
||
/* Check if the address matches any watched address. */
|
||
state = aarch64_get_debug_reg_state (ptid_get_pid (inferior_ptid));
|
||
for (i = aarch64_num_wp_regs - 1; i >= 0; --i)
|
||
{
|
||
const unsigned int len = aarch64_watchpoint_length (state->dr_ctrl_wp[i]);
|
||
const CORE_ADDR addr_trap = (CORE_ADDR) siginfo.si_addr;
|
||
const CORE_ADDR addr_watch = state->dr_addr_wp[i];
|
||
|
||
if (state->dr_ref_count_wp[i]
|
||
&& DR_CONTROL_ENABLED (state->dr_ctrl_wp[i])
|
||
&& addr_trap >= addr_watch
|
||
&& addr_trap < addr_watch + len)
|
||
{
|
||
*addr_p = addr_trap;
|
||
return 1;
|
||
}
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Implement the "to_stopped_by_watchpoint" target_ops method. */
|
||
|
||
static int
|
||
aarch64_linux_stopped_by_watchpoint (struct target_ops *ops)
|
||
{
|
||
CORE_ADDR addr;
|
||
|
||
return aarch64_linux_stopped_data_address (ops, &addr);
|
||
}
|
||
|
||
/* Implement the "to_watchpoint_addr_within_range" target_ops method. */
|
||
|
||
static int
|
||
aarch64_linux_watchpoint_addr_within_range (struct target_ops *target,
|
||
CORE_ADDR addr,
|
||
CORE_ADDR start, int length)
|
||
{
|
||
return start <= addr && start + length - 1 >= addr;
|
||
}
|
||
|
||
/* Define AArch64 maintenance commands. */
|
||
|
||
static void
|
||
add_show_debug_regs_command (void)
|
||
{
|
||
/* A maintenance command to enable printing the internal DRi mirror
|
||
variables. */
|
||
add_setshow_boolean_cmd ("show-debug-regs", class_maintenance,
|
||
&show_debug_regs, _("\
|
||
Set whether to show variables that mirror the AArch64 debug registers."), _("\
|
||
Show whether to show variables that mirror the AArch64 debug registers."), _("\
|
||
Use \"on\" to enable, \"off\" to disable.\n\
|
||
If enabled, the debug registers values are shown when GDB inserts\n\
|
||
or removes a hardware breakpoint or watchpoint, and when the inferior\n\
|
||
triggers a breakpoint or watchpoint."),
|
||
NULL,
|
||
NULL,
|
||
&maintenance_set_cmdlist,
|
||
&maintenance_show_cmdlist);
|
||
}
|
||
|
||
/* -Wmissing-prototypes. */
|
||
void _initialize_aarch64_linux_nat (void);
|
||
|
||
void
|
||
_initialize_aarch64_linux_nat (void)
|
||
{
|
||
struct target_ops *t;
|
||
|
||
/* Fill in the generic GNU/Linux methods. */
|
||
t = linux_target ();
|
||
|
||
add_show_debug_regs_command ();
|
||
|
||
/* Add our register access methods. */
|
||
t->to_fetch_registers = aarch64_linux_fetch_inferior_registers;
|
||
t->to_store_registers = aarch64_linux_store_inferior_registers;
|
||
|
||
t->to_read_description = aarch64_linux_read_description;
|
||
|
||
t->to_can_use_hw_breakpoint = aarch64_linux_can_use_hw_breakpoint;
|
||
t->to_insert_hw_breakpoint = aarch64_linux_insert_hw_breakpoint;
|
||
t->to_remove_hw_breakpoint = aarch64_linux_remove_hw_breakpoint;
|
||
t->to_region_ok_for_hw_watchpoint =
|
||
aarch64_linux_region_ok_for_hw_watchpoint;
|
||
t->to_insert_watchpoint = aarch64_linux_insert_watchpoint;
|
||
t->to_remove_watchpoint = aarch64_linux_remove_watchpoint;
|
||
t->to_stopped_by_watchpoint = aarch64_linux_stopped_by_watchpoint;
|
||
t->to_stopped_data_address = aarch64_linux_stopped_data_address;
|
||
t->to_watchpoint_addr_within_range =
|
||
aarch64_linux_watchpoint_addr_within_range;
|
||
|
||
/* Override the GNU/Linux inferior startup hook. */
|
||
super_post_startup_inferior = t->to_post_startup_inferior;
|
||
t->to_post_startup_inferior = aarch64_linux_child_post_startup_inferior;
|
||
|
||
/* Register the target. */
|
||
linux_nat_add_target (t);
|
||
linux_nat_set_new_thread (t, aarch64_linux_new_thread);
|
||
linux_nat_set_new_fork (t, aarch64_linux_new_fork);
|
||
linux_nat_set_forget_process (t, aarch64_forget_process);
|
||
linux_nat_set_prepare_to_resume (t, aarch64_linux_prepare_to_resume);
|
||
}
|