summaryrefslogtreecommitdiffstats
path: root/lib/libcompiler_rt/clzti2.c
diff options
context:
space:
mode:
authorpascal <pascal@openbsd.org>2016-09-05 11:36:10 +0000
committerpascal <pascal@openbsd.org>2016-09-05 11:36:10 +0000
commita303f987e7ef7d1b60e04cf8b1f06edb794137d8 (patch)
tree45f1c146ea15009060dad6a1d72c753f0dbba747 /lib/libcompiler_rt/clzti2.c
parentMissing local. (diff)
downloadwireguard-openbsd-a303f987e7ef7d1b60e04cf8b1f06edb794137d8.tar.xz
wireguard-openbsd-a303f987e7ef7d1b60e04cf8b1f06edb794137d8.zip
Import libcompiler_rt 3.9.0, LLVM's replacement for libgcc.
This is the lib/builtin directory of the compiler-rt source tarball. comments/ok patrick@, ok kettenis@
Diffstat (limited to 'lib/libcompiler_rt/clzti2.c')
-rw-r--r--lib/libcompiler_rt/clzti2.c33
1 files changed, 33 insertions, 0 deletions
diff --git a/lib/libcompiler_rt/clzti2.c b/lib/libcompiler_rt/clzti2.c
new file mode 100644
index 00000000000..15a7b3c9000
--- /dev/null
+++ b/lib/libcompiler_rt/clzti2.c
@@ -0,0 +1,33 @@
+/* ===-- clzti2.c - Implement __clzti2 -------------------------------------===
+ *
+ * The LLVM Compiler Infrastructure
+ *
+ * This file is dual licensed under the MIT and the University of Illinois Open
+ * Source Licenses. See LICENSE.TXT for details.
+ *
+ * ===----------------------------------------------------------------------===
+ *
+ * This file implements __clzti2 for the compiler_rt library.
+ *
+ * ===----------------------------------------------------------------------===
+ */
+
+#include "int_lib.h"
+
+#ifdef CRT_HAS_128BIT
+
+/* Returns: the number of leading 0-bits */
+
+/* Precondition: a != 0 */
+
+COMPILER_RT_ABI si_int
+__clzti2(ti_int a)
+{
+ twords x;
+ x.all = a;
+ const di_int f = -(x.s.high == 0);
+ return __builtin_clzll((x.s.high & ~f) | (x.s.low & f)) +
+ ((si_int)f & ((si_int)(sizeof(di_int) * CHAR_BIT)));
+}
+
+#endif /* CRT_HAS_128BIT */