Merge branch 'linux-2.6' into for-linus

[powerpc.git] / include / asm-powerpc / bug.h

diff --git a/include/asm-powerpc/bug.h b/include/asm-powerpc/bug.h
index b001ecb..978b2c7 100644 (file)
--- a/include/asm-powerpc/bug.h
+++ b/include/asm-powerpc/bug.h
@@ -1,5 +1,6 @@
 #ifndef _ASM_POWERPC_BUG_H
 #define _ASM_POWERPC_BUG_H
+#ifdef __KERNEL__
 
 #include <asm/asm-compat.h>
 /*
@@ -29,35 +30,63 @@ struct bug_entry *find_bug(unsigned long bugaddr);
 
 #ifdef CONFIG_BUG
 
+/*
+ * BUG_ON() and WARN_ON() do their best to cooperate with compile-time
+ * optimisations. However depending on the complexity of the condition
+ * some compiler versions may not produce optimal results.
+ */
+
 #define BUG() do {                                                      \
        __asm__ __volatile__(                                            \
                "1:     twi 31,0,0\n"                                    \
                ".section __bug_table,\"a\"\n"                           \
-               "\t"PPC_LONG"   1b,%0,%1,%2\n"                   \
+               "\t"PPC_LONG"   1b,%0,%1,%2\n"                           \
                ".previous"                                              \
                : : "i" (__LINE__), "i" (__FILE__), "i" (__FUNCTION__)); \
 } while (0)
 
 #define BUG_ON(x) do {                                         \
-       __asm__ __volatile__(                                   \
+       if (__builtin_constant_p(x)) {                          \
+               if (x)                                          \
+                       BUG();                                  \
+       } else {                                                \
+               __asm__ __volatile__(                           \
                "1:     "PPC_TLNEI"     %0,0\n"                 \
                ".section __bug_table,\"a\"\n"                  \
-               "\t"PPC_LONG"   1b,%1,%2,%3\n"          \
+               "\t"PPC_LONG"   1b,%1,%2,%3\n"                  \
                ".previous"                                     \
                : : "r" ((long)(x)), "i" (__LINE__),            \
                    "i" (__FILE__), "i" (__FUNCTION__));        \
+       }                                                       \
 } while (0)
 
-#define WARN_ON(x) do {                                                \
+#define __WARN() do {                                          \
        __asm__ __volatile__(                                   \
+               "1:     twi 31,0,0\n"                           \
+               ".section __bug_table,\"a\"\n"                  \
+               "\t"PPC_LONG"   1b,%0,%1,%2\n"                  \
+               ".previous"                                     \
+               : : "i" (__LINE__ + BUG_WARNING_TRAP),          \
+                   "i" (__FILE__), "i" (__FUNCTION__));        \
+} while (0)
+
+#define WARN_ON(x) ({                                          \
+       typeof(x) __ret_warn_on = (x);                          \
+       if (__builtin_constant_p(__ret_warn_on)) {              \
+               if (__ret_warn_on)                              \
+                       __WARN();                               \
+       } else {                                                \
+               __asm__ __volatile__(                           \
                "1:     "PPC_TLNEI"     %0,0\n"                 \
                ".section __bug_table,\"a\"\n"                  \
-               "\t"PPC_LONG"   1b,%1,%2,%3\n"          \
+               "\t"PPC_LONG"   1b,%1,%2,%3\n"                  \
                ".previous"                                     \
-               : : "r" ((long)(x)),                            \
+               : : "r" (__ret_warn_on),                        \
                    "i" (__LINE__ + BUG_WARNING_TRAP),          \
                    "i" (__FILE__), "i" (__FUNCTION__));        \
-} while (0)
+       }                                                       \
+       unlikely(__ret_warn_on);                                \
+})
 
 #define HAVE_ARCH_BUG
 #define HAVE_ARCH_BUG_ON
@@ -67,4 +96,5 @@ struct bug_entry *find_bug(unsigned long bugaddr);
 
 #include <asm-generic/bug.h>
 
+#endif /* __KERNEL__ */
 #endif /* _ASM_POWERPC_BUG_H */