diff options
Diffstat (limited to 'gdb/amd64-linux-tdep.c')
| -rw-r--r-- | gdb/amd64-linux-tdep.c | 67 |
1 files changed, 66 insertions, 1 deletions
diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c index 9fa01739bc3..316b1f3faf8 100644 --- a/gdb/amd64-linux-tdep.c +++ b/gdb/amd64-linux-tdep.c @@ -1,6 +1,6 @@ /* Target-dependent code for GNU/Linux x86-64. - Copyright (C) 2001, 2003, 2004, 2005 Free Software Foundation, Inc. + Copyright (C) 2001, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. Contributed by Jiri Smid, SuSE Labs. This file is part of GDB. @@ -26,6 +26,9 @@ #include "regcache.h" #include "osabi.h" #include "symtab.h" +#include "gdbtypes.h" +#include "reggroups.h" +#include "amd64-linux-tdep.h" #include "gdb_string.h" @@ -199,6 +202,61 @@ static int amd64_linux_sc_reg_offset[] = -1 /* %gs */ }; +/* Replacement register functions which know about %orig_rax. */ + +static const char * +amd64_linux_register_name (int reg) +{ + if (reg == AMD64_LINUX_ORIG_RAX_REGNUM) + return "orig_rax"; + + return amd64_register_name (reg); +} + +static struct type * +amd64_linux_register_type (struct gdbarch *gdbarch, int reg) +{ + if (reg == AMD64_LINUX_ORIG_RAX_REGNUM) + return builtin_type_int64; + + return amd64_register_type (gdbarch, reg); +} + +static int +amd64_linux_register_reggroup_p (struct gdbarch *gdbarch, int regnum, + struct reggroup *group) +{ + if (regnum == AMD64_LINUX_ORIG_RAX_REGNUM) + return (group == system_reggroup + || group == save_reggroup + || group == restore_reggroup); + return default_register_reggroup_p (gdbarch, regnum, group); +} + +/* Set the program counter for process PTID to PC. */ + +static void +amd64_linux_write_pc (CORE_ADDR pc, ptid_t ptid) +{ + write_register_pid (AMD64_RIP_REGNUM, pc, ptid); + + /* We must be careful with modifying the program counter. If we + just interrupted a system call, the kernel might try to restart + it when we resume the inferior. On restarting the system call, + the kernel will try backing up the program counter even though it + no longer points at the system call. This typically results in a + SIGSEGV or SIGILL. We can prevent this by writing `-1' in the + "orig_rax" pseudo-register. + + Note that "orig_rax" is saved when setting up a dummy call frame. + This means that it is properly restored when that frame is + popped, and that the interrupted system call will be restarted + when we resume the inferior on return from a function call from + within GDB. In all other cases the system call will not be + restarted. */ + write_register_pid (AMD64_LINUX_ORIG_RAX_REGNUM, -1, ptid); +} + static void amd64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) { @@ -219,6 +277,13 @@ amd64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) set_solib_svr4_fetch_link_map_offsets (gdbarch, svr4_lp64_fetch_link_map_offsets); + /* Add the %orig_rax register used for syscall restarting. */ + set_gdbarch_write_pc (gdbarch, amd64_linux_write_pc); + set_gdbarch_num_regs (gdbarch, AMD64_LINUX_NUM_REGS); + set_gdbarch_register_name (gdbarch, amd64_linux_register_name); + set_gdbarch_register_type (gdbarch, amd64_linux_register_type); + set_gdbarch_register_reggroup_p (gdbarch, amd64_linux_register_reggroup_p); + /* Enable TLS support. */ set_gdbarch_fetch_tls_load_module_address (gdbarch, svr4_fetch_objfile_link_map); |