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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/ffsdi2.c
parentMissing local. (diff)
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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/ffsdi2.c')
-rw-r--r--lib/libcompiler_rt/ffsdi2.c33
1 files changed, 33 insertions, 0 deletions
diff --git a/lib/libcompiler_rt/ffsdi2.c b/lib/libcompiler_rt/ffsdi2.c
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+++ b/lib/libcompiler_rt/ffsdi2.c
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+/* ===-- ffsdi2.c - Implement __ffsdi2 -------------------------------------===
+ *
+ * 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 __ffsdi2 for the compiler_rt library.
+ *
+ * ===----------------------------------------------------------------------===
+ */
+
+#include "int_lib.h"
+
+/* Returns: the index of the least significant 1-bit in a, or
+ * the value zero if a is zero. The least significant bit is index one.
+ */
+
+COMPILER_RT_ABI si_int
+__ffsdi2(di_int a)
+{
+ dwords x;
+ x.all = a;
+ if (x.s.low == 0)
+ {
+ if (x.s.high == 0)
+ return 0;
+ return __builtin_ctz(x.s.high) + (1 + sizeof(si_int) * CHAR_BIT);
+ }
+ return __builtin_ctz(x.s.low) + 1;
+}