1 files changed, 27 insertions, 16 deletions
diff --git a/include/asm-alpha/string.h b/include/asm-alpha/string.h
index 6ef1f4120..4b83c8291 100644
--- a/include/asm-alpha/string.h
+++ b/include/asm-alpha/string.h
@@ -3,29 +3,40 @@
 
 #ifdef __KERNEL__
 
-extern void * __constant_c_memset(void *, unsigned long, long);
-extern void * __memset(void *, char, size_t);
-
 /*
- * Ugh. Gcc uses "bcopy()" internally for structure assignments.
+ * GCC of any recent vintage doesn't do stupid things with bcopy.  Of
+ * EGCS-devel vintage, it knows all about expanding memcpy inline.
+ * For things other than EGCS-devel but still recent, GCC will expand
+ * __builtin_memcpy as a simple call to memcpy.
+ *
+ * Similarly for a memset with data = 0.
  */
-#define __HAVE_ARCH_BCOPY
 
-/*
- * Define "memcpy()" to something else, otherwise gcc will
- * corrupt that too into a "bcopy".  Also, some day we might
- * want to do a separate inlined constant-size memcpy (for 8
- * and 16 byte user<->kernel structure copying).
- */
 #define __HAVE_ARCH_MEMCPY
+/* For backward compatibility with modules.  Unused otherwise.  */
 extern void * __memcpy(void *, const void *, size_t);
-#define memcpy __memcpy
+
+#if __GNUC__ > 2 || __GNUC_MINOR__ >= 8
+#define memcpy __builtin_memcpy
+#endif
 
 #define __HAVE_ARCH_MEMSET
-#define memset(s, c, count) \
-(__builtin_constant_p(c) ? \
- __constant_c_memset((s),(0x0101010101010101UL*(unsigned char)c),(count)) : \
- __memset((s),(c),(count)))
+extern void * __constant_c_memset(void *, unsigned long, long);
+extern void * __memset(void *, char, size_t);
+
+#if __GNUC__ > 2 || __GNUC_MINOR__ >= 8
+#define memset(s, c, n)							    \
+(__builtin_constant_p(c)						    \
+ ? (__builtin_constant_p(n) && (c) == 0					    \
+    ? __builtin_memset((s),0,(n)) 					    \
+    : __constant_c_memset((s),0x0101010101010101UL*(unsigned char)(c),(n))) \
+ : __memset((s),(c),(n)))
+#else
+#define memset(s, c, n)							\
+(__builtin_constant_p(c)						\
+ ? __constant_c_memset((s),0x0101010101010101UL*(unsigned char)(c),(n)) \
+ : __memset((s),(c),(n)))
+#endif
 
 #define __HAVE_ARCH_STRCPY
 #define __HAVE_ARCH_STRNCPY