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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /include/uapi/linux/const.h
Initial import
Diffstat (limited to 'include/uapi/linux/const.h')
-rw-r--r--include/uapi/linux/const.h27
1 files changed, 27 insertions, 0 deletions
diff --git a/include/uapi/linux/const.h b/include/uapi/linux/const.h
new file mode 100644
index 000000000..c872bfd25
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+++ b/include/uapi/linux/const.h
@@ -0,0 +1,27 @@
+/* const.h: Macros for dealing with constants. */
+
+#ifndef _LINUX_CONST_H
+#define _LINUX_CONST_H
+
+/* Some constant macros are used in both assembler and
+ * C code. Therefore we cannot annotate them always with
+ * 'UL' and other type specifiers unilaterally. We
+ * use the following macros to deal with this.
+ *
+ * Similarly, _AT() will cast an expression with a type in C, but
+ * leave it unchanged in asm.
+ */
+
+#ifdef __ASSEMBLY__
+#define _AC(X,Y) X
+#define _AT(T,X) X
+#else
+#define __AC(X,Y) (X##Y)
+#define _AC(X,Y) __AC(X,Y)
+#define _AT(T,X) ((T)(X))
+#endif
+
+#define _BITUL(x) (_AC(1,UL) << (x))
+#define _BITULL(x) (_AC(1,ULL) << (x))
+
+#endif /* !(_LINUX_CONST_H) */