binutils-gdb/gdb/arch/arm-get-next-pcs.c

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Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
/* Common code for ARM software single stepping support.
Copyright (C) 1988-2016 Free Software Foundation, Inc.
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
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 3 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, see <http://www.gnu.org/licenses/>. */
#include "common-defs.h"
#include "gdb_vecs.h"
#include "common-regcache.h"
#include "arm.h"
#include "arm-get-next-pcs.h"
/* See arm-get-next-pcs.h. */
void
arm_get_next_pcs_ctor (struct arm_get_next_pcs *self,
struct arm_get_next_pcs_ops *ops,
int byte_order,
int byte_order_for_code,
[ARM] Make thumb2_breakpoint static again This patch makes thumb2_breakpoint static. When writing this patch, I find the only reason we keep thumb2_breakpoint extern is that it is used as an argument passed to arm_gdbserver_get_next_pcs. However, field arm_thumb2_breakpoint is only used in a null check in thumb_get_next_pcs_raw, so I wonder why do need to pass thumb2_breakpoint to arm_gdbserver_get_next_pcs. thumb2_breakpoint was added by Daniel Jacobowitz in order to support single-step IT block https://sourceware.org/ml/gdb-patches/2010-01/msg00624.html the logic there was if we have 32-bit thumb-2 breakpoint defined, we can safely single-step IT block, otherwise, we can't. Daniel didn't want to use 16-bit thumb BKPT instruction, because it triggers even on instruction which should be executed. Secondly, using 16-bit thumb illegal instruction on top of 32-bit thumb instruction may break the meaning of original IT blocks, because the other 16-bit can be regarded as an instruction. See more explanations from Daniel's kernel patch http://www.spinics.net/lists/arm-kernel/msg80476.html Let us back to this patch, GDB/GDBserver can safely single step IT block if thumb2_breakpoint is defined, but the single step logic doesn't have to know the thumb-2 breakpoint instruction. Only breakpoint insertion mechanism decides to use which breakpoint instruction. In the software single step code, instead of pass thumb2_breakpoint, we can pass a boolean variable has_thumb2_breakpoint indicate whether the target has thumb-2 breakpoint defined, which is equivalent to the original code. Regression tested on arm-linux. No regression. gdb: 2016-01-14 Yao Qi <yao.qi@linaro.org> * arch/arm-get-next-pcs.c (arm_get_next_pcs_ctor): Change argument arm_thumb2_breakpoint to has_thumb2_breakpoint. (thumb_get_next_pcs_raw): Check has_thumb2_breakpoint instead. * arch/arm-get-next-pcs.h (struct arm_get_next_pcs) <arm_thumb2_breakpoint>: Remove. <has_thumb2_breakpoint>: New field. (arm_get_next_pcs_ctor): Update declaration. * arm-linux-tdep.c (arm_linux_software_single_step): Pass 1 to arm_get_next_pcs_ctor. * arm-tdep.c (arm_software_single_step): Pass 0 to arm_get_next_pcs_ctor. gdb/gdbserver: 2016-01-14 Yao Qi <yao.qi@linaro.org> * linux-aarch32-low.c (thumb2_breakpoint): Make it static. * linux-aarch32-low.h (thumb2_breakpoint): Remove declaration. * linux-arm-low.c (arm_gdbserver_get_next_pcs): Pass 1 to arm_get_next_pcs_ctor.
2016-01-14 17:36:43 +08:00
int has_thumb2_breakpoint,
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
struct regcache *regcache)
{
self->ops = ops;
self->byte_order = byte_order;
self->byte_order_for_code = byte_order_for_code;
[ARM] Make thumb2_breakpoint static again This patch makes thumb2_breakpoint static. When writing this patch, I find the only reason we keep thumb2_breakpoint extern is that it is used as an argument passed to arm_gdbserver_get_next_pcs. However, field arm_thumb2_breakpoint is only used in a null check in thumb_get_next_pcs_raw, so I wonder why do need to pass thumb2_breakpoint to arm_gdbserver_get_next_pcs. thumb2_breakpoint was added by Daniel Jacobowitz in order to support single-step IT block https://sourceware.org/ml/gdb-patches/2010-01/msg00624.html the logic there was if we have 32-bit thumb-2 breakpoint defined, we can safely single-step IT block, otherwise, we can't. Daniel didn't want to use 16-bit thumb BKPT instruction, because it triggers even on instruction which should be executed. Secondly, using 16-bit thumb illegal instruction on top of 32-bit thumb instruction may break the meaning of original IT blocks, because the other 16-bit can be regarded as an instruction. See more explanations from Daniel's kernel patch http://www.spinics.net/lists/arm-kernel/msg80476.html Let us back to this patch, GDB/GDBserver can safely single step IT block if thumb2_breakpoint is defined, but the single step logic doesn't have to know the thumb-2 breakpoint instruction. Only breakpoint insertion mechanism decides to use which breakpoint instruction. In the software single step code, instead of pass thumb2_breakpoint, we can pass a boolean variable has_thumb2_breakpoint indicate whether the target has thumb-2 breakpoint defined, which is equivalent to the original code. Regression tested on arm-linux. No regression. gdb: 2016-01-14 Yao Qi <yao.qi@linaro.org> * arch/arm-get-next-pcs.c (arm_get_next_pcs_ctor): Change argument arm_thumb2_breakpoint to has_thumb2_breakpoint. (thumb_get_next_pcs_raw): Check has_thumb2_breakpoint instead. * arch/arm-get-next-pcs.h (struct arm_get_next_pcs) <arm_thumb2_breakpoint>: Remove. <has_thumb2_breakpoint>: New field. (arm_get_next_pcs_ctor): Update declaration. * arm-linux-tdep.c (arm_linux_software_single_step): Pass 1 to arm_get_next_pcs_ctor. * arm-tdep.c (arm_software_single_step): Pass 0 to arm_get_next_pcs_ctor. gdb/gdbserver: 2016-01-14 Yao Qi <yao.qi@linaro.org> * linux-aarch32-low.c (thumb2_breakpoint): Make it static. * linux-aarch32-low.h (thumb2_breakpoint): Remove declaration. * linux-arm-low.c (arm_gdbserver_get_next_pcs): Pass 1 to arm_get_next_pcs_ctor.
2016-01-14 17:36:43 +08:00
self->has_thumb2_breakpoint = has_thumb2_breakpoint;
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
self->regcache = regcache;
}
/* Checks for an atomic sequence of instructions beginning with a LDREX{,B,H,D}
instruction and ending with a STREX{,B,H,D} instruction. If such a sequence
is found, attempt to step through it. The end of the sequence address is
added to the next_pcs list. */
static VEC (CORE_ADDR) *
thumb_deal_with_atomic_sequence_raw (struct arm_get_next_pcs *self)
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
{
int byte_order_for_code = self->byte_order_for_code;
CORE_ADDR breaks[2] = {-1, -1};
CORE_ADDR pc = regcache_read_pc (self->regcache);
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
CORE_ADDR loc = pc;
unsigned short insn1, insn2;
int insn_count;
int index;
int last_breakpoint = 0; /* Defaults to 0 (no breakpoints placed). */
const int atomic_sequence_length = 16; /* Instruction sequence length. */
ULONGEST status, itstate;
VEC (CORE_ADDR) *next_pcs = NULL;
/* We currently do not support atomic sequences within an IT block. */
status = regcache_raw_get_unsigned (self->regcache, ARM_PS_REGNUM);
itstate = ((status >> 8) & 0xfc) | ((status >> 25) & 0x3);
if (itstate & 0x0f)
return NULL;
/* Assume all atomic sequences start with a ldrex{,b,h,d} instruction. */
insn1 = self->ops->read_mem_uint (loc, 2, byte_order_for_code);
loc += 2;
if (thumb_insn_size (insn1) != 4)
return NULL;
insn2 = self->ops->read_mem_uint (loc, 2, byte_order_for_code);
loc += 2;
if (!((insn1 & 0xfff0) == 0xe850
|| ((insn1 & 0xfff0) == 0xe8d0 && (insn2 & 0x00c0) == 0x0040)))
return NULL;
/* Assume that no atomic sequence is longer than "atomic_sequence_length"
instructions. */
for (insn_count = 0; insn_count < atomic_sequence_length; ++insn_count)
{
insn1 = self->ops->read_mem_uint (loc, 2,byte_order_for_code);
loc += 2;
if (thumb_insn_size (insn1) != 4)
{
/* Assume that there is at most one conditional branch in the
atomic sequence. If a conditional branch is found, put a
breakpoint in its destination address. */
if ((insn1 & 0xf000) == 0xd000 && bits (insn1, 8, 11) != 0x0f)
{
if (last_breakpoint > 0)
return NULL; /* More than one conditional branch found,
fallback to the standard code. */
breaks[1] = loc + 2 + (sbits (insn1, 0, 7) << 1);
last_breakpoint++;
}
/* We do not support atomic sequences that use any *other*
instructions but conditional branches to change the PC.
Fall back to standard code to avoid losing control of
execution. */
else if (thumb_instruction_changes_pc (insn1))
return NULL;
}
else
{
insn2 = self->ops->read_mem_uint (loc, 2, byte_order_for_code);
loc += 2;
/* Assume that there is at most one conditional branch in the
atomic sequence. If a conditional branch is found, put a
breakpoint in its destination address. */
if ((insn1 & 0xf800) == 0xf000
&& (insn2 & 0xd000) == 0x8000
&& (insn1 & 0x0380) != 0x0380)
{
int sign, j1, j2, imm1, imm2;
unsigned int offset;
sign = sbits (insn1, 10, 10);
imm1 = bits (insn1, 0, 5);
imm2 = bits (insn2, 0, 10);
j1 = bit (insn2, 13);
j2 = bit (insn2, 11);
offset = (sign << 20) + (j2 << 19) + (j1 << 18);
offset += (imm1 << 12) + (imm2 << 1);
if (last_breakpoint > 0)
return 0; /* More than one conditional branch found,
fallback to the standard code. */
breaks[1] = loc + offset;
last_breakpoint++;
}
/* We do not support atomic sequences that use any *other*
instructions but conditional branches to change the PC.
Fall back to standard code to avoid losing control of
execution. */
else if (thumb2_instruction_changes_pc (insn1, insn2))
return NULL;
/* If we find a strex{,b,h,d}, we're done. */
if ((insn1 & 0xfff0) == 0xe840
|| ((insn1 & 0xfff0) == 0xe8c0 && (insn2 & 0x00c0) == 0x0040))
break;
}
}
/* If we didn't find the strex{,b,h,d}, we cannot handle the sequence. */
if (insn_count == atomic_sequence_length)
return NULL;
/* Insert a breakpoint right after the end of the atomic sequence. */
breaks[0] = loc;
/* Check for duplicated breakpoints. Check also for a breakpoint
placed (branch instruction's destination) anywhere in sequence. */
if (last_breakpoint
&& (breaks[1] == breaks[0]
|| (breaks[1] >= pc && breaks[1] < loc)))
last_breakpoint = 0;
/* Adds the breakpoints to the list to be inserted. */
for (index = 0; index <= last_breakpoint; index++)
VEC_safe_push (CORE_ADDR, next_pcs, MAKE_THUMB_ADDR (breaks[index]));
return next_pcs;
}
/* Checks for an atomic sequence of instructions beginning with a LDREX{,B,H,D}
instruction and ending with a STREX{,B,H,D} instruction. If such a sequence
is found, attempt to step through it. The end of the sequence address is
added to the next_pcs list. */
static VEC (CORE_ADDR) *
arm_deal_with_atomic_sequence_raw (struct arm_get_next_pcs *self)
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
{
int byte_order_for_code = self->byte_order_for_code;
CORE_ADDR breaks[2] = {-1, -1};
CORE_ADDR pc = regcache_read_pc (self->regcache);
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
CORE_ADDR loc = pc;
unsigned int insn;
int insn_count;
int index;
int last_breakpoint = 0; /* Defaults to 0 (no breakpoints placed). */
const int atomic_sequence_length = 16; /* Instruction sequence length. */
VEC (CORE_ADDR) *next_pcs = NULL;
/* Assume all atomic sequences start with a ldrex{,b,h,d} instruction.
Note that we do not currently support conditionally executed atomic
instructions. */
insn = self->ops->read_mem_uint (loc, 4, byte_order_for_code);
loc += 4;
if ((insn & 0xff9000f0) != 0xe1900090)
return NULL;
/* Assume that no atomic sequence is longer than "atomic_sequence_length"
instructions. */
for (insn_count = 0; insn_count < atomic_sequence_length; ++insn_count)
{
insn = self->ops->read_mem_uint (loc, 4, byte_order_for_code);
loc += 4;
/* Assume that there is at most one conditional branch in the atomic
sequence. If a conditional branch is found, put a breakpoint in
its destination address. */
if (bits (insn, 24, 27) == 0xa)
{
if (last_breakpoint > 0)
return NULL; /* More than one conditional branch found, fallback
to the standard single-step code. */
breaks[1] = BranchDest (loc - 4, insn);
last_breakpoint++;
}
/* We do not support atomic sequences that use any *other* instructions
but conditional branches to change the PC. Fall back to standard
code to avoid losing control of execution. */
else if (arm_instruction_changes_pc (insn))
return NULL;
/* If we find a strex{,b,h,d}, we're done. */
if ((insn & 0xff9000f0) == 0xe1800090)
break;
}
/* If we didn't find the strex{,b,h,d}, we cannot handle the sequence. */
if (insn_count == atomic_sequence_length)
return NULL;
/* Insert a breakpoint right after the end of the atomic sequence. */
breaks[0] = loc;
/* Check for duplicated breakpoints. Check also for a breakpoint
placed (branch instruction's destination) anywhere in sequence. */
if (last_breakpoint
&& (breaks[1] == breaks[0]
|| (breaks[1] >= pc && breaks[1] < loc)))
last_breakpoint = 0;
/* Adds the breakpoints to the list to be inserted. */
for (index = 0; index <= last_breakpoint; index++)
VEC_safe_push (CORE_ADDR, next_pcs, breaks[index]);
return next_pcs;
}
/* Find the next possible PCs for thumb mode. */
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
static VEC (CORE_ADDR) *
thumb_get_next_pcs_raw (struct arm_get_next_pcs *self)
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
{
int byte_order = self->byte_order;
int byte_order_for_code = self->byte_order_for_code;
CORE_ADDR pc = regcache_read_pc (self->regcache);
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
unsigned long pc_val = ((unsigned long) pc) + 4; /* PC after prefetch */
unsigned short inst1;
CORE_ADDR nextpc = pc + 2; /* Default is next instruction. */
unsigned long offset;
ULONGEST status, itstate;
struct regcache *regcache = self->regcache;
VEC (CORE_ADDR) * next_pcs = NULL;
nextpc = MAKE_THUMB_ADDR (nextpc);
pc_val = MAKE_THUMB_ADDR (pc_val);
inst1 = self->ops->read_mem_uint (pc, 2, byte_order_for_code);
/* Thumb-2 conditional execution support. There are eight bits in
the CPSR which describe conditional execution state. Once
reconstructed (they're in a funny order), the low five bits
describe the low bit of the condition for each instruction and
how many instructions remain. The high three bits describe the
base condition. One of the low four bits will be set if an IT
block is active. These bits read as zero on earlier
processors. */
status = regcache_raw_get_unsigned (regcache, ARM_PS_REGNUM);
itstate = ((status >> 8) & 0xfc) | ((status >> 25) & 0x3);
/* If-Then handling. On GNU/Linux, where this routine is used, we
use an undefined instruction as a breakpoint. Unlike BKPT, IT
can disable execution of the undefined instruction. So we might
miss the breakpoint if we set it on a skipped conditional
instruction. Because conditional instructions can change the
flags, affecting the execution of further instructions, we may
need to set two breakpoints. */
[ARM] Make thumb2_breakpoint static again This patch makes thumb2_breakpoint static. When writing this patch, I find the only reason we keep thumb2_breakpoint extern is that it is used as an argument passed to arm_gdbserver_get_next_pcs. However, field arm_thumb2_breakpoint is only used in a null check in thumb_get_next_pcs_raw, so I wonder why do need to pass thumb2_breakpoint to arm_gdbserver_get_next_pcs. thumb2_breakpoint was added by Daniel Jacobowitz in order to support single-step IT block https://sourceware.org/ml/gdb-patches/2010-01/msg00624.html the logic there was if we have 32-bit thumb-2 breakpoint defined, we can safely single-step IT block, otherwise, we can't. Daniel didn't want to use 16-bit thumb BKPT instruction, because it triggers even on instruction which should be executed. Secondly, using 16-bit thumb illegal instruction on top of 32-bit thumb instruction may break the meaning of original IT blocks, because the other 16-bit can be regarded as an instruction. See more explanations from Daniel's kernel patch http://www.spinics.net/lists/arm-kernel/msg80476.html Let us back to this patch, GDB/GDBserver can safely single step IT block if thumb2_breakpoint is defined, but the single step logic doesn't have to know the thumb-2 breakpoint instruction. Only breakpoint insertion mechanism decides to use which breakpoint instruction. In the software single step code, instead of pass thumb2_breakpoint, we can pass a boolean variable has_thumb2_breakpoint indicate whether the target has thumb-2 breakpoint defined, which is equivalent to the original code. Regression tested on arm-linux. No regression. gdb: 2016-01-14 Yao Qi <yao.qi@linaro.org> * arch/arm-get-next-pcs.c (arm_get_next_pcs_ctor): Change argument arm_thumb2_breakpoint to has_thumb2_breakpoint. (thumb_get_next_pcs_raw): Check has_thumb2_breakpoint instead. * arch/arm-get-next-pcs.h (struct arm_get_next_pcs) <arm_thumb2_breakpoint>: Remove. <has_thumb2_breakpoint>: New field. (arm_get_next_pcs_ctor): Update declaration. * arm-linux-tdep.c (arm_linux_software_single_step): Pass 1 to arm_get_next_pcs_ctor. * arm-tdep.c (arm_software_single_step): Pass 0 to arm_get_next_pcs_ctor. gdb/gdbserver: 2016-01-14 Yao Qi <yao.qi@linaro.org> * linux-aarch32-low.c (thumb2_breakpoint): Make it static. * linux-aarch32-low.h (thumb2_breakpoint): Remove declaration. * linux-arm-low.c (arm_gdbserver_get_next_pcs): Pass 1 to arm_get_next_pcs_ctor.
2016-01-14 17:36:43 +08:00
if (self->has_thumb2_breakpoint)
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
{
if ((inst1 & 0xff00) == 0xbf00 && (inst1 & 0x000f) != 0)
{
/* An IT instruction. Because this instruction does not
modify the flags, we can accurately predict the next
executed instruction. */
itstate = inst1 & 0x00ff;
pc += thumb_insn_size (inst1);
while (itstate != 0 && ! condition_true (itstate >> 4, status))
{
inst1 = self->ops->read_mem_uint (pc, 2,byte_order_for_code);
pc += thumb_insn_size (inst1);
itstate = thumb_advance_itstate (itstate);
}
VEC_safe_push (CORE_ADDR, next_pcs, MAKE_THUMB_ADDR (pc));
return next_pcs;
}
else if (itstate != 0)
{
/* We are in a conditional block. Check the condition. */
if (! condition_true (itstate >> 4, status))
{
/* Advance to the next executed instruction. */
pc += thumb_insn_size (inst1);
itstate = thumb_advance_itstate (itstate);
while (itstate != 0 && ! condition_true (itstate >> 4, status))
{
inst1 = self->ops->read_mem_uint (pc, 2, byte_order_for_code);
pc += thumb_insn_size (inst1);
itstate = thumb_advance_itstate (itstate);
}
VEC_safe_push (CORE_ADDR, next_pcs, MAKE_THUMB_ADDR (pc));
return next_pcs;
}
else if ((itstate & 0x0f) == 0x08)
{
/* This is the last instruction of the conditional
block, and it is executed. We can handle it normally
because the following instruction is not conditional,
and we must handle it normally because it is
permitted to branch. Fall through. */
}
else
{
int cond_negated;
/* There are conditional instructions after this one.
If this instruction modifies the flags, then we can
not predict what the next executed instruction will
be. Fortunately, this instruction is architecturally
forbidden to branch; we know it will fall through.
Start by skipping past it. */
pc += thumb_insn_size (inst1);
itstate = thumb_advance_itstate (itstate);
/* Set a breakpoint on the following instruction. */
gdb_assert ((itstate & 0x0f) != 0);
VEC_safe_push (CORE_ADDR, next_pcs, MAKE_THUMB_ADDR (pc));
cond_negated = (itstate >> 4) & 1;
/* Skip all following instructions with the same
condition. If there is a later instruction in the IT
block with the opposite condition, set the other
breakpoint there. If not, then set a breakpoint on
the instruction after the IT block. */
do
{
inst1 = self->ops->read_mem_uint (pc, 2, byte_order_for_code);
pc += thumb_insn_size (inst1);
itstate = thumb_advance_itstate (itstate);
}
while (itstate != 0 && ((itstate >> 4) & 1) == cond_negated);
VEC_safe_push (CORE_ADDR, next_pcs, MAKE_THUMB_ADDR (pc));
return next_pcs;
}
}
}
else if (itstate & 0x0f)
{
/* We are in a conditional block. Check the condition. */
int cond = itstate >> 4;
if (! condition_true (cond, status))
{
/* Advance to the next instruction. All the 32-bit
instructions share a common prefix. */
VEC_safe_push (CORE_ADDR, next_pcs,
MAKE_THUMB_ADDR (pc + thumb_insn_size (inst1)));
}
return next_pcs;
/* Otherwise, handle the instruction normally. */
}
if ((inst1 & 0xff00) == 0xbd00) /* pop {rlist, pc} */
{
CORE_ADDR sp;
/* Fetch the saved PC from the stack. It's stored above
all of the other registers. */
offset = bitcount (bits (inst1, 0, 7)) * INT_REGISTER_SIZE;
sp = regcache_raw_get_unsigned (regcache, ARM_SP_REGNUM);
nextpc = self->ops->read_mem_uint (sp + offset, 4, byte_order);
}
else if ((inst1 & 0xf000) == 0xd000) /* conditional branch */
{
unsigned long cond = bits (inst1, 8, 11);
if (cond == 0x0f) /* 0x0f = SWI */
{
nextpc = self->ops->syscall_next_pc (self, pc);
}
else if (cond != 0x0f && condition_true (cond, status))
nextpc = pc_val + (sbits (inst1, 0, 7) << 1);
}
else if ((inst1 & 0xf800) == 0xe000) /* unconditional branch */
{
nextpc = pc_val + (sbits (inst1, 0, 10) << 1);
}
else if (thumb_insn_size (inst1) == 4) /* 32-bit instruction */
{
unsigned short inst2;
inst2 = self->ops->read_mem_uint (pc + 2, 2, byte_order_for_code);
/* Default to the next instruction. */
nextpc = pc + 4;
nextpc = MAKE_THUMB_ADDR (nextpc);
if ((inst1 & 0xf800) == 0xf000 && (inst2 & 0x8000) == 0x8000)
{
/* Branches and miscellaneous control instructions. */
if ((inst2 & 0x1000) != 0 || (inst2 & 0xd001) == 0xc000)
{
/* B, BL, BLX. */
int j1, j2, imm1, imm2;
imm1 = sbits (inst1, 0, 10);
imm2 = bits (inst2, 0, 10);
j1 = bit (inst2, 13);
j2 = bit (inst2, 11);
offset = ((imm1 << 12) + (imm2 << 1));
offset ^= ((!j2) << 22) | ((!j1) << 23);
nextpc = pc_val + offset;
/* For BLX make sure to clear the low bits. */
if (bit (inst2, 12) == 0)
nextpc = nextpc & 0xfffffffc;
}
else if (inst1 == 0xf3de && (inst2 & 0xff00) == 0x3f00)
{
/* SUBS PC, LR, #imm8. */
nextpc = regcache_raw_get_unsigned (regcache, ARM_LR_REGNUM);
nextpc -= inst2 & 0x00ff;
}
else if ((inst2 & 0xd000) == 0x8000 && (inst1 & 0x0380) != 0x0380)
{
/* Conditional branch. */
if (condition_true (bits (inst1, 6, 9), status))
{
int sign, j1, j2, imm1, imm2;
sign = sbits (inst1, 10, 10);
imm1 = bits (inst1, 0, 5);
imm2 = bits (inst2, 0, 10);
j1 = bit (inst2, 13);
j2 = bit (inst2, 11);
offset = (sign << 20) + (j2 << 19) + (j1 << 18);
offset += (imm1 << 12) + (imm2 << 1);
nextpc = pc_val + offset;
}
}
}
else if ((inst1 & 0xfe50) == 0xe810)
{
/* Load multiple or RFE. */
int rn, offset, load_pc = 1;
rn = bits (inst1, 0, 3);
if (bit (inst1, 7) && !bit (inst1, 8))
{
/* LDMIA or POP */
if (!bit (inst2, 15))
load_pc = 0;
offset = bitcount (inst2) * 4 - 4;
}
else if (!bit (inst1, 7) && bit (inst1, 8))
{
/* LDMDB */
if (!bit (inst2, 15))
load_pc = 0;
offset = -4;
}
else if (bit (inst1, 7) && bit (inst1, 8))
{
/* RFEIA */
offset = 0;
}
else if (!bit (inst1, 7) && !bit (inst1, 8))
{
/* RFEDB */
offset = -8;
}
else
load_pc = 0;
if (load_pc)
{
CORE_ADDR addr = regcache_raw_get_unsigned (regcache, rn);
nextpc = self->ops->read_mem_uint (addr + offset, 4, byte_order);
}
}
else if ((inst1 & 0xffef) == 0xea4f && (inst2 & 0xfff0) == 0x0f00)
{
/* MOV PC or MOVS PC. */
nextpc = regcache_raw_get_unsigned (regcache, bits (inst2, 0, 3));
nextpc = MAKE_THUMB_ADDR (nextpc);
}
else if ((inst1 & 0xff70) == 0xf850 && (inst2 & 0xf000) == 0xf000)
{
/* LDR PC. */
CORE_ADDR base;
int rn, load_pc = 1;
rn = bits (inst1, 0, 3);
base = regcache_raw_get_unsigned (regcache, rn);
if (rn == ARM_PC_REGNUM)
{
base = (base + 4) & ~(CORE_ADDR) 0x3;
if (bit (inst1, 7))
base += bits (inst2, 0, 11);
else
base -= bits (inst2, 0, 11);
}
else if (bit (inst1, 7))
base += bits (inst2, 0, 11);
else if (bit (inst2, 11))
{
if (bit (inst2, 10))
{
if (bit (inst2, 9))
base += bits (inst2, 0, 7);
else
base -= bits (inst2, 0, 7);
}
}
else if ((inst2 & 0x0fc0) == 0x0000)
{
int shift = bits (inst2, 4, 5), rm = bits (inst2, 0, 3);
base += regcache_raw_get_unsigned (regcache, rm) << shift;
}
else
/* Reserved. */
load_pc = 0;
if (load_pc)
nextpc
= self->ops->read_mem_uint (base, 4, byte_order);
}
else if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf000)
{
/* TBB. */
CORE_ADDR tbl_reg, table, offset, length;
tbl_reg = bits (inst1, 0, 3);
if (tbl_reg == 0x0f)
table = pc + 4; /* Regcache copy of PC isn't right yet. */
else
table = regcache_raw_get_unsigned (regcache, tbl_reg);
offset = regcache_raw_get_unsigned (regcache, bits (inst2, 0, 3));
length = 2 * self->ops->read_mem_uint (table + offset, 1, byte_order);
nextpc = pc_val + length;
}
else if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf010)
{
/* TBH. */
CORE_ADDR tbl_reg, table, offset, length;
tbl_reg = bits (inst1, 0, 3);
if (tbl_reg == 0x0f)
table = pc + 4; /* Regcache copy of PC isn't right yet. */
else
table = regcache_raw_get_unsigned (regcache, tbl_reg);
offset = 2 * regcache_raw_get_unsigned (regcache, bits (inst2, 0, 3));
length = 2 * self->ops->read_mem_uint (table + offset, 2, byte_order);
nextpc = pc_val + length;
}
}
else if ((inst1 & 0xff00) == 0x4700) /* bx REG, blx REG */
{
if (bits (inst1, 3, 6) == 0x0f)
nextpc = UNMAKE_THUMB_ADDR (pc_val);
else
nextpc = regcache_raw_get_unsigned (regcache, bits (inst1, 3, 6));
}
else if ((inst1 & 0xff87) == 0x4687) /* mov pc, REG */
{
if (bits (inst1, 3, 6) == 0x0f)
nextpc = pc_val;
else
nextpc = regcache_raw_get_unsigned (regcache, bits (inst1, 3, 6));
nextpc = MAKE_THUMB_ADDR (nextpc);
}
else if ((inst1 & 0xf500) == 0xb100)
{
/* CBNZ or CBZ. */
int imm = (bit (inst1, 9) << 6) + (bits (inst1, 3, 7) << 1);
ULONGEST reg = regcache_raw_get_unsigned (regcache, bits (inst1, 0, 2));
if (bit (inst1, 11) && reg != 0)
nextpc = pc_val + imm;
else if (!bit (inst1, 11) && reg == 0)
nextpc = pc_val + imm;
}
VEC_safe_push (CORE_ADDR, next_pcs, nextpc);
return next_pcs;
}
/* Get the raw next possible addresses. PC in next_pcs is the current program
counter, which is assumed to be executing in ARM mode.
The values returned have the execution state of the next instruction
encoded in it. Use IS_THUMB_ADDR () to see whether the instruction is
in Thumb-State, and gdbarch_addr_bits_remove () to get the plain memory
address in GDB and arm_addr_bits_remove in GDBServer. */
static VEC (CORE_ADDR) *
arm_get_next_pcs_raw (struct arm_get_next_pcs *self)
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
{
int byte_order = self->byte_order;
int byte_order_for_code = self->byte_order_for_code;
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
unsigned long pc_val;
unsigned long this_instr = 0;
unsigned long status;
CORE_ADDR nextpc;
struct regcache *regcache = self->regcache;
CORE_ADDR pc = regcache_read_pc (self->regcache);
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
VEC (CORE_ADDR) *next_pcs = NULL;
pc_val = (unsigned long) pc;
this_instr = self->ops->read_mem_uint (pc, 4, byte_order_for_code);
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
status = regcache_raw_get_unsigned (regcache, ARM_PS_REGNUM);
nextpc = (CORE_ADDR) (pc_val + 4); /* Default case */
if (bits (this_instr, 28, 31) == INST_NV)
switch (bits (this_instr, 24, 27))
{
case 0xa:
case 0xb:
{
/* Branch with Link and change to Thumb. */
nextpc = BranchDest (pc, this_instr);
nextpc |= bit (this_instr, 24) << 1;
nextpc = MAKE_THUMB_ADDR (nextpc);
break;
}
case 0xc:
case 0xd:
case 0xe:
/* Coprocessor register transfer. */
if (bits (this_instr, 12, 15) == 15)
error (_("Invalid update to pc in instruction"));
break;
}
else if (condition_true (bits (this_instr, 28, 31), status))
{
switch (bits (this_instr, 24, 27))
{
case 0x0:
case 0x1: /* data processing */
case 0x2:
case 0x3:
{
unsigned long operand1, operand2, result = 0;
unsigned long rn;
int c;
if (bits (this_instr, 12, 15) != 15)
break;
if (bits (this_instr, 22, 25) == 0
&& bits (this_instr, 4, 7) == 9) /* multiply */
error (_("Invalid update to pc in instruction"));
/* BX <reg>, BLX <reg> */
if (bits (this_instr, 4, 27) == 0x12fff1
|| bits (this_instr, 4, 27) == 0x12fff3)
{
rn = bits (this_instr, 0, 3);
nextpc = ((rn == ARM_PC_REGNUM)
? (pc_val + 8)
: regcache_raw_get_unsigned (regcache, rn));
VEC_safe_push (CORE_ADDR, next_pcs, nextpc);
return next_pcs;
}
/* Multiply into PC. */
c = (status & FLAG_C) ? 1 : 0;
rn = bits (this_instr, 16, 19);
operand1 = ((rn == ARM_PC_REGNUM)
? (pc_val + 8)
: regcache_raw_get_unsigned (regcache, rn));
if (bit (this_instr, 25))
{
unsigned long immval = bits (this_instr, 0, 7);
unsigned long rotate = 2 * bits (this_instr, 8, 11);
operand2 = ((immval >> rotate) | (immval << (32 - rotate)))
& 0xffffffff;
}
else /* operand 2 is a shifted register. */
operand2 = shifted_reg_val (regcache, this_instr, c,
pc_val, status);
switch (bits (this_instr, 21, 24))
{
case 0x0: /*and */
result = operand1 & operand2;
break;
case 0x1: /*eor */
result = operand1 ^ operand2;
break;
case 0x2: /*sub */
result = operand1 - operand2;
break;
case 0x3: /*rsb */
result = operand2 - operand1;
break;
case 0x4: /*add */
result = operand1 + operand2;
break;
case 0x5: /*adc */
result = operand1 + operand2 + c;
break;
case 0x6: /*sbc */
result = operand1 - operand2 + c;
break;
case 0x7: /*rsc */
result = operand2 - operand1 + c;
break;
case 0x8:
case 0x9:
case 0xa:
case 0xb: /* tst, teq, cmp, cmn */
result = (unsigned long) nextpc;
break;
case 0xc: /*orr */
result = operand1 | operand2;
break;
case 0xd: /*mov */
/* Always step into a function. */
result = operand2;
break;
case 0xe: /*bic */
result = operand1 & ~operand2;
break;
case 0xf: /*mvn */
result = ~operand2;
break;
}
nextpc = self->ops->addr_bits_remove (self, result);
break;
}
case 0x4:
case 0x5: /* data transfer */
case 0x6:
case 0x7:
if (bits (this_instr, 25, 27) == 0x3 && bit (this_instr, 4) == 1)
{
/* Media instructions and architecturally undefined
instructions. */
break;
}
if (bit (this_instr, 20))
{
/* load */
if (bits (this_instr, 12, 15) == 15)
{
/* rd == pc */
unsigned long rn;
unsigned long base;
if (bit (this_instr, 22))
error (_("Invalid update to pc in instruction"));
/* byte write to PC */
rn = bits (this_instr, 16, 19);
base = ((rn == ARM_PC_REGNUM)
? (pc_val + 8)
: regcache_raw_get_unsigned (regcache, rn));
if (bit (this_instr, 24))
{
/* pre-indexed */
int c = (status & FLAG_C) ? 1 : 0;
unsigned long offset =
(bit (this_instr, 25)
? shifted_reg_val (regcache, this_instr, c,
pc_val, status)
: bits (this_instr, 0, 11));
if (bit (this_instr, 23))
base += offset;
else
base -= offset;
}
nextpc
= (CORE_ADDR) self->ops->read_mem_uint ((CORE_ADDR) base,
4, byte_order);
}
}
break;
case 0x8:
case 0x9: /* block transfer */
if (bit (this_instr, 20))
{
/* LDM */
if (bit (this_instr, 15))
{
/* loading pc */
int offset = 0;
CORE_ADDR rn_val_offset = 0;
unsigned long rn_val
= regcache_raw_get_unsigned (regcache,
bits (this_instr, 16, 19));
if (bit (this_instr, 23))
{
/* up */
unsigned long reglist = bits (this_instr, 0, 14);
offset = bitcount (reglist) * 4;
if (bit (this_instr, 24)) /* pre */
offset += 4;
}
else if (bit (this_instr, 24))
offset = -4;
rn_val_offset = rn_val + offset;
nextpc = (CORE_ADDR) self->ops->read_mem_uint (rn_val_offset,
4, byte_order);
}
}
break;
case 0xb: /* branch & link */
case 0xa: /* branch */
{
nextpc = BranchDest (pc, this_instr);
break;
}
case 0xc:
case 0xd:
case 0xe: /* coproc ops */
break;
case 0xf: /* SWI */
{
nextpc = self->ops->syscall_next_pc (self, pc);
}
break;
default:
error (_("Bad bit-field extraction"));
Support software single step on ARM in GDBServer This patch teaches GDBServer how to software single step on ARM linux by sharing code with GDB. The arm_get_next_pcs function in GDB is now shared with GDBServer. So that GDBServer can use the function to return the possible addresses of the next PC. A proper shared context was also needed so that we could share the code, this context is described in the arm_get_next_pcs structure. Testing : No regressions, tested on ubuntu 14.04 ARMv7 and x86. With gdbserver-{native,extended} / { -marm -mthumb } gdb/ChangeLog: * Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o, arm-linux.o. (ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * arch/arm-get-next-pcs.c: New file. * arch/arm-get-next-pcs.h: New file. * arch/arm-linux.h: New file. * arch/arm-linux.c: New file. * arm.c: Include common-regcache.c. (thumb_advance_itstate): Moved from arm-tdep.c. (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm.h (submask): Move macro from arm-tdep.h (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_advance_itstate): Moved declaration from arm-tdep.h (arm_instruction_changes_pc): Likewise. (thumb_instruction_changes_pc): Likewise. (thumb2_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. * arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h arch/arm-linux.h. (arm_linux_get_next_pcs_ops): New struct. (ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT, ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT, ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack layout defines to arch/arm-linux.h. (arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c. (arm_linux_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.c: Include arch/arm-get-next-pcs.h. (arm_get_next_pcs_ops): New struct. (submask): Move macro to arm.h. (bit): Likewise. (bits): Likewise. (sbits): Likewise. (BranchDest): Likewise. (thumb_instruction_changes_pc): Move to arm.c (thumb2_instruction_changes_pc): Likewise. (arm_instruction_changes_pc): Likewise. (shifted_reg_val): Likewise. (thumb_advance_itstate): Likewise. (thumb_get_next_pc_raw): Move to arm-get-next-pcs.c. (arm_get_next_pc_raw): Likewise. (arm_get_next_pc): Likewise. (thumb_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence_raw): Likewise. (arm_deal_with_atomic_sequence): Likewise. (arm_get_next_pcs_read_memory_unsigned_integer): New function. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_software_single_step): Adjust for arm_get_next_pcs implementation. * arm-tdep.h: (arm_get_next_pc): Remove declaration. (arm_get_next_pcs_read_memory_unsigned_integer): New declaration. (arm_get_next_pcs_addr_bits_remove): Likewise. (arm_get_next_pcs_syscall_next_pc): Likewise. (arm_get_next_pcs_is_thumb): Likewise. (arm_deal_with_atomic_sequence: Remove declaration. * common/gdb_vecs.h: Add CORE_ADDR vector definition. * configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o, arm-linux.o. (arm*-wince-pe): Add arm-get-next-pcs.o. (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o, arm-get-next-pcs.o (arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o. (arm*-*-openbsd*): Likewise. (arm*-*-symbianelf*): Likewise. (arm*-*-*): Likewise. * symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h. gdb/gdbserver/ChangeLog: * Makefile.in (SFILES): Append arch/arm-linux.c, arch/arm-get-next-pcs.c. (arm-linux.o): New rule. (arm-get-next-pcs.o): New rule. * configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o. * linux-aarch32-low.c (arm_abi_breakpoint): Remove macro. Moved to linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): Make non-static. * linux-aarch32-low.h (arm_abi_breakpoint): New macro. Moved from linux-aarch32-low.c. (arm_eabi_breakpoint, arm_breakpoint): Likewise. (arm_breakpoint_len, thumb_breakpoint): Likewise. (thumb_breakpoint_len, thumb2_breakpoint): Likewise. (thumb2_breakpoint_len): Likewise. (arm_is_thumb_mode): New declaration. * linux-arm-low.c: Include arch/arm-linux.h aarch/arm-get-next-pcs.h, sys/syscall.h. (get_next_pcs_ops): New struct. (get_next_pcs_addr_bits_remove): New function. (get_next_pcs_is_thumb): New function. (get_next_pcs_read_memory_unsigned_integer): Likewise. (arm_sigreturn_next_pc): Likewise. (get_next_pcs_syscall_next_pc): Likewise. (arm_gdbserver_get_next_pcs): Likewise. (struct linux_target_ops) <arm_gdbserver_get_next_pcs>: Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h.
2015-12-19 00:33:59 +08:00
return next_pcs;
}
}
VEC_safe_push (CORE_ADDR, next_pcs, nextpc);
return next_pcs;
}
/* See arm-get-next-pcs.h. */
VEC (CORE_ADDR) *
arm_get_next_pcs (struct arm_get_next_pcs *self)
{
VEC (CORE_ADDR) *next_pcs = NULL;
if (self->ops->is_thumb (self))
{
next_pcs = thumb_deal_with_atomic_sequence_raw (self);
if (next_pcs == NULL)
next_pcs = thumb_get_next_pcs_raw (self);
}
else
{
next_pcs = arm_deal_with_atomic_sequence_raw (self);
if (next_pcs == NULL)
next_pcs = arm_get_next_pcs_raw (self);
}
[ARM] Fixup PC in software single step When I exercise GDBserver software single step, I see the following error, which has been already handled by GDB properly. In GDBserver log, we can see, GDBserver tries to single step instruction on 0xb6e0a6e4, and destination address is 0xffff0fe0, stop pc is 0xb6e0a6e4 Writing f001f0e7 to 0xffff0fe0 in process 7132 Failed to insert breakpoint at 0xffff0fe0 (Input/output error). Failed to insert breakpoint at 0xffff0fe0 (-1). (gdb) disassemble __aeabi_read_tp,+8 Dump of assembler code from 0xb6e0a6e0 to 0xb6e0a6e8: 0xb6e0a6e0 <__aeabi_read_tp+0>: mvn r0, #61440 ; 0xf000 0xb6e0a6e4 <__aeabi_read_tp+4>: sub pc, r0, #31 however, it fails inserting breakpoint there. This problem has already fixed by GDB, see comments in arm-linux-tdep.c:arm_linux_software_single_step /* The Linux kernel offers some user-mode helpers in a high page. We can not read this page (as of 2.6.23), and even if we could then we couldn't set breakpoints in it, and even if we could then the atomic operations would fail when interrupted. They are all called as functions and return to the address in LR, so step to there instead. */ so we need to do the same thing in GDB side as well. This patch adds a new field fixup in arm_get_next_pcs_ops, so that we can fix up PC for arm-linux target. In this way, both GDB and GDBserver can single step instructions going to kernel helpers. gdb: 2016-02-12 Yao Qi <yao.qi@linaro.org> * arch/arm-get-next-pcs.c (arm_get_next_pcs): Call self->ops->fixup if it isn't NULL. * arch/arm-get-next-pcs.h: Include gdb_vecs.h. (struct arm_get_next_pcs_ops) <fixup>: New field. * arch/arm-linux.c: Include common-regcache.h and arch/arm-get-next-pcs.h. (arm_linux_get_next_pcs_fixup): New function. * arch/arm-linux.h (arm_linux_get_next_pcs_fixup): Declare. * arm-linux-tdep.c (arm_linux_get_next_pcs_ops): Initialize it with arm_linux_get_next_pcs_fixup. (arm_linux_software_single_step): Move code to arm_linux_get_next_pcs_fixup. * arm-tdep.c (arm_get_next_pcs_ops): Initialize it. gdb/gdbserver: 2016-02-12 Yao Qi <yao.qi@linaro.org> * linux-arm-low.c (get_next_pcs_ops): Initialize it with arm_linux_get_next_pcs_fixup.
2016-02-09 00:05:31 +08:00
if (self->ops->fixup != NULL)
{
CORE_ADDR nextpc;
int i;
for (i = 0; VEC_iterate (CORE_ADDR, next_pcs, i, nextpc); i++)
{
nextpc = self->ops->fixup (self, nextpc);
VEC_replace (CORE_ADDR, next_pcs, i, nextpc);
}
}
return next_pcs;
}