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Diffstat (limited to 'sysdeps/s390/s390-32/backtrace.c')
-rw-r--r--sysdeps/s390/s390-32/backtrace.c81
1 files changed, 81 insertions, 0 deletions
diff --git a/sysdeps/s390/s390-32/backtrace.c b/sysdeps/s390/s390-32/backtrace.c
new file mode 100644
index 0000000000..8e3ca7ecca
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+++ b/sysdeps/s390/s390-32/backtrace.c
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+/* Return backtrace of current program state.
+ Copyright (C) 2000, 2001 Free Software Foundation, Inc.
+ Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
+ This file is part of the GNU C Library.
+
+ 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,
+ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include <execinfo.h>
+#include <stddef.h>
+
+/* This is a global variable set at program start time. It marks the
+ highest used stack address. */
+extern void *__libc_stack_end;
+
+
+/* This is the stack layout we see for every non-leaf function.
+ size offset
+ %r15 -> +------------------+
+ 4 | back chain | 0
+ 4 | end of stack | 4
+ 8 | glue | 8
+ 8 | scratch | 16
+ 40 | save area r6-r15 | 24
+ 16 | save area f4,f6 | 64
+ 16 | empty | 80
+ +------------------+
+ r14 in the save area holds the return address.
+*/
+
+struct layout
+{
+ int back_chain;
+ int end_of_stack;
+ int glue[2];
+ int scratch[2];
+ int save_grps[10];
+ int save_fp[4];
+ int empty[2];
+};
+
+int
+__backtrace (array, size)
+ void **array;
+ int size;
+{
+ /* We assume that all the code is generated with frame pointers set. */
+ struct layout *stack;
+ int cnt = 0;
+
+ asm ("LR %0,%%r15" : "=d" (stack) );
+ /* We skip the call to this function, it makes no sense to record it. */
+ stack = (struct layout *) stack->back_chain;
+ while (cnt < size)
+ {
+ if (stack == NULL || (void *) stack > __libc_stack_end)
+ /* This means the address is out of range. Note that for the
+ toplevel we see a frame pointer with value NULL which clearly is
+ out of range. */
+ break;
+
+ array[cnt++] = stack->save_grps[9];
+
+ stack = (struct layout *) stack->back_chain;
+ }
+
+ return cnt;
+}
+weak_alias (__backtrace, backtrace)