diff options
Diffstat (limited to 'REORG.TODO/sysdeps/sparc/backtrace.c')
| -rw-r--r-- | REORG.TODO/sysdeps/sparc/backtrace.c | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/sparc/backtrace.c b/REORG.TODO/sysdeps/sparc/backtrace.c new file mode 100644 index 0000000000..2887031c72 --- /dev/null +++ b/REORG.TODO/sysdeps/sparc/backtrace.c @@ -0,0 +1,159 @@ +/* Return backtrace of current program state. + Copyright (C) 2013-2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by David S. Miller <davem@davemloft.net> + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + The GNU C Library 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If + not, see <http://www.gnu.org/licenses/>. */ + +#include <execinfo.h> +#include <stddef.h> +#include <sysdep.h> +#include <sys/trap.h> +#include <dlfcn.h> +#include <unwind.h> +#include <backtrace.h> + +struct layout +{ + unsigned long locals[8]; + unsigned long ins[6]; + unsigned long next; + void *return_address; +}; + +struct trace_arg +{ + void **array; + _Unwind_Word cfa; + int cnt; + int size; +}; + +#ifdef SHARED +static _Unwind_Reason_Code (*unwind_backtrace) (_Unwind_Trace_Fn, void *); +static _Unwind_Ptr (*unwind_getip) (struct _Unwind_Context *); +static _Unwind_Word (*unwind_getcfa) (struct _Unwind_Context *); +static void *libgcc_handle; + +/* Dummy version in case libgcc_s does not contain the real code. */ +static _Unwind_Word +dummy_getcfa (struct _Unwind_Context *ctx __attribute__ ((unused))) +{ + return 0; +} + +static void +init (void) +{ + libgcc_handle = __libc_dlopen ("libgcc_s.so.1"); + + if (libgcc_handle == NULL) + return; + + unwind_backtrace = __libc_dlsym (libgcc_handle, "_Unwind_Backtrace"); + unwind_getip = __libc_dlsym (libgcc_handle, "_Unwind_GetIP"); + if (unwind_getip == NULL) + unwind_backtrace = NULL; + unwind_getcfa = (__libc_dlsym (libgcc_handle, "_Unwind_GetCFA") + ?: dummy_getcfa); +} +#else +# define unwind_backtrace _Unwind_Backtrace +# define unwind_getip _Unwind_GetIP +# define unwind_getcfa _Unwind_GetCFA +#endif + +static _Unwind_Reason_Code +backtrace_helper (struct _Unwind_Context *ctx, void *a) +{ + struct trace_arg *arg = a; + _Unwind_Ptr ip; + + /* We are first called with address in the __backtrace function. + Skip it. */ + if (arg->cnt != -1) + { + ip = unwind_getip (ctx); + arg->array[arg->cnt] = (void *) ip; + + /* Check whether we make any progress. */ + _Unwind_Word cfa = unwind_getcfa (ctx); + + if (arg->cnt > 0 && arg->array[arg->cnt - 1] == arg->array[arg->cnt] + && cfa == arg->cfa) + return _URC_END_OF_STACK; + arg->cfa = cfa; + } + if (++arg->cnt == arg->size) + return _URC_END_OF_STACK; + return _URC_NO_REASON; +} + +int +__backtrace (void **array, int size) +{ + struct trace_arg arg = { .array = array, .cfa = 0, .size = size, .cnt = -1 }; + bool use_unwinder; + int count; + + if (size <= 0) + return 0; + + use_unwinder = true; +#ifdef SHARED + __libc_once_define (static, once); + + __libc_once (once, init); + if (unwind_backtrace == NULL) + use_unwinder = false; +#endif + + if (use_unwinder == false) + { + struct layout *current; + unsigned long fp, i7; + + asm volatile ("mov %%fp, %0" : "=r"(fp)); + asm volatile ("mov %%i7, %0" : "=r"(i7)); + current = (struct layout *) (fp + BACKTRACE_STACK_BIAS); + + array[0] = (void *) i7; + + if (size == 1) + return 1; + + backtrace_flush_register_windows(); + for (count = 1; count < size; count++) + { + array[count] = current->return_address; + if (!current->next) + break; + current = (struct layout *) (current->next + BACKTRACE_STACK_BIAS); + } + } + else + { + unwind_backtrace (backtrace_helper, &arg); + + /* _Unwind_Backtrace seems to put NULL address above + _start. Fix it up here. */ + if (arg.cnt > 1 && arg.array[arg.cnt - 1] == NULL) + --arg.cnt; + count = arg.cnt != -1 ? arg.cnt : 0; + } + return count; +} +weak_alias (__backtrace, backtrace) +libc_hidden_def (__backtrace) |