compiler*.h: sync include/linux/compiler*.h with Linux 3.16

Copy them from Linux v3.16 tag.
My main motivation of this commit is to add compiler-clang.h.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Jeroen Hofstee <jeroen@myspectrum.nl>

include/linux/compiler-intel.h

@@ -0,0 +1,40 @@
+#ifndef __LINUX_COMPILER_H
+#error "Please don't include <linux/compiler-intel.h> directly, include <linux/compiler.h> instead."
+#endif
+
+#ifdef __ECC
+
+/* Some compiler specific definitions are overwritten here
+ * for Intel ECC compiler
+ */
+
+#include <asm/intrinsics.h>
+
+/* Intel ECC compiler doesn't support gcc specific asm stmts.
+ * It uses intrinsics to do the equivalent things.
+ */
+#undef RELOC_HIDE
+#undef OPTIMIZER_HIDE_VAR
+
+#define RELOC_HIDE(ptr, off)					\
+  ({ unsigned long __ptr;					\
+     __ptr = (unsigned long) (ptr);				\
+    (typeof(ptr)) (__ptr + (off)); })
+
+/* This should act as an optimization barrier on var.
+ * Given that this compiler does not have inline assembly, a compiler barrier
+ * is the best we can do.
+ */
+#define OPTIMIZER_HIDE_VAR(var) barrier()
+
+/* Intel ECC compiler doesn't support __builtin_types_compatible_p() */
+#define __must_be_array(a) 0
+
+#endif
+
+#ifndef __HAVE_BUILTIN_BSWAP16__
+/* icc has this, but it's called _bswap16 */
+#define __HAVE_BUILTIN_BSWAP16__
+#define __builtin_bswap16 _bswap16
+#endif
+