From d9311bfaf572cf14af577a66e79c51c491553552 Mon Sep 17 00:00:00 2001 From: Antoine Tremblay Date: Fri, 18 Dec 2015 11:33:59 -0500 Subject: 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) : Initialize. * linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h. * server.h: Include gdb_vecs.h. --- gdb/arch/arm-linux.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) create mode 100644 gdb/arch/arm-linux.c (limited to 'gdb/arch/arm-linux.c') diff --git a/gdb/arch/arm-linux.c b/gdb/arch/arm-linux.c new file mode 100644 index 0000000..5d871e2 --- /dev/null +++ b/gdb/arch/arm-linux.c @@ -0,0 +1,57 @@ +/* Common target dependent code for GNU/Linux on ARM systems. + + Copyright (C) 1999-2015 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 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 . */ + +#include "common-defs.h" +#include "arch/arm.h" +#include "arm-linux.h" + +/* Calculate the offset from stack pointer of the pc register on the stack + in the case of a sigreturn or sigreturn_rt syscall. */ +int +arm_linux_sigreturn_next_pc_offset (unsigned long sp, + unsigned long sp_data, + unsigned long svc_number, + int is_sigreturn) +{ + /* Offset of R0 register. */ + int r0_offset = 0; + /* Offset of PC register. */ + int pc_offset = 0; + + if (is_sigreturn) + { + if (sp_data == ARM_NEW_SIGFRAME_MAGIC) + r0_offset = ARM_UCONTEXT_SIGCONTEXT + ARM_SIGCONTEXT_R0; + else + r0_offset = ARM_SIGCONTEXT_R0; + } + else + { + if (sp_data == sp + ARM_OLD_RT_SIGFRAME_SIGINFO) + r0_offset = ARM_OLD_RT_SIGFRAME_UCONTEXT; + else + r0_offset = ARM_NEW_RT_SIGFRAME_UCONTEXT; + + r0_offset += ARM_UCONTEXT_SIGCONTEXT + ARM_SIGCONTEXT_R0; + } + + pc_offset = r0_offset + INT_REGISTER_SIZE * ARM_PC_REGNUM; + + return pc_offset; +} -- cgit v1.1