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-rw-r--r--sysdeps/powerpc/powerpc32/backtrace.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/sysdeps/powerpc/powerpc32/backtrace.c b/sysdeps/powerpc/powerpc32/backtrace.c
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+++ b/sysdeps/powerpc/powerpc32/backtrace.c
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+/* Return backtrace of current program state.
+ Copyright (C) 1998, 2000 Free Software Foundation, Inc.
+ 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 Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; 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>
+#include <bp-checks.h>
+
+/* This is the stack layout we see with every stack frame.
+ Note that every routine is required by the ABI to lay out the stack
+ like this.
+
+ +----------------+ +-----------------+
+ %r1 -> | %r1 last frame--------> | %r1 last frame--->... --> NULL
+ | | | |
+ | (unused) | | return address |
+ +----------------+ +-----------------+
+*/
+struct layout
+{
+ struct layout *__unbounded next;
+ void *__unbounded return_address;
+};
+
+int
+__backtrace (void **array, int size)
+{
+ struct layout *current;
+ int count;
+
+ /* Force gcc to spill LR. */
+ asm volatile ("" : "=l"(current));
+
+ /* Get the address on top-of-stack. */
+ asm volatile ("lwz %0,0(1)" : "=r"(current));
+ current = BOUNDED_1 (current);
+
+ for ( count = 0;
+ current != NULL && count < size;
+ current = BOUNDED_1 (current->next), count++)
+ array[count] = current->return_address;
+
+ /* It's possible the second-last stack frame can't return
+ (that is, it's __libc_start_main), in which case
+ the CRT startup code will have set its LR to 'NULL'. */
+ if (count > 0 && array[count-1] == NULL)
+ count--;
+
+ return count;
+}
+weak_alias (__backtrace, backtrace)