bug.h

Go to the documentation of this file.

#ifndef __ASM_CRISv10_ARCH_BUG_H
#define __ASM_CRISv10_ARCH_BUG_H

#include <linux/stringify.h>

#ifdef CONFIG_BUG
#ifdef CONFIG_DEBUG_BUGVERBOSE
/* The BUG() macro is used for marking obviously incorrect code paths.
 * It will cause a message with the file name and line number to be printed,
 * and then cause an oops.  The message is actually printed by handle_BUG()
 * in arch/cris/kernel/traps.c, and the reason we use this method of storing
 * the file name and line number is that we do not want to affect the registers
 * by calling printk() before causing the oops.
 */

#define BUG_PREFIX 0x0D7F
#define BUG_MAGIC  0x00001234

struct bug_frame {
    unsigned short prefix;
    unsigned int magic;
    unsigned short clear;
    unsigned short movu;
    unsigned short line;
    unsigned short jump;
    unsigned char *filename;
};

#if 0
/* Unfortunately this version of the macro does not work due to a problem
 * with the compiler (aka a bug) when compiling with -O2, which sometimes
 * erroneously causes the second input to be stored in a register...
 */
#define BUG()                               \
    __asm__ __volatile__ ("clear.d [" __stringify(BUG_MAGIC) "]\n\t"\
                "movu.w %0,$r0\n\t"         \
                "jump %1\n\t"               \
                : : "i" (__LINE__), "i" (__FILE__))
#else
/* This version will have to do for now, until the compiler is fixed.
 * The drawbacks of this version are that the file name will appear multiple
 * times in the .rodata section, and that __LINE__ and __FILE__ can probably
 * not be used like this with newer versions of gcc.
 */
#define BUG()                               \
    __asm__ __volatile__ ("clear.d [" __stringify(BUG_MAGIC) "]\n\t"\
                  "movu.w " __stringify(__LINE__) ",$r0\n\t"\
                  "jump 0f\n\t"             \
                  ".section .rodata\n"          \
                  "0:\t.string \"" __FILE__ "\"\n\t"    \
                  ".previous")
#endif

#else

/* This just causes an oops. */
#define BUG() (*(int *)0 = 0)

#endif

#define HAVE_ARCH_BUG
#endif

#include <asm-generic/bug.h>

#endif