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authorDevtools Arcadia <[email protected]>2022-02-07 18:08:42 +0300
committerDevtools Arcadia <[email protected]>2022-02-07 18:08:42 +0300
commit1110808a9d39d4b808aef724c861a2e1a38d2a69 (patch)
treee26c9fed0de5d9873cce7e00bc214573dc2195b7 /contrib/libs/cxxsupp/builtins/ffsti2.c
intermediate changes
ref:cde9a383711a11544ce7e107a78147fb96cc4029
Diffstat (limited to 'contrib/libs/cxxsupp/builtins/ffsti2.c')
-rw-r--r--contrib/libs/cxxsupp/builtins/ffsti2.c37
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diff --git a/contrib/libs/cxxsupp/builtins/ffsti2.c b/contrib/libs/cxxsupp/builtins/ffsti2.c
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+++ b/contrib/libs/cxxsupp/builtins/ffsti2.c
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+/* ===-- ffsti2.c - Implement __ffsti2 -------------------------------------===
+ *
+ * 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 __ffsti2 for the compiler_rt library.
+ *
+ * ===----------------------------------------------------------------------===
+ */
+
+#include "int_lib.h"
+
+#ifdef CRT_HAS_128BIT
+
+/* 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
+__ffsti2(ti_int a)
+{
+ twords x;
+ x.all = a;
+ if (x.s.low == 0)
+ {
+ if (x.s.high == 0)
+ return 0;
+ return __builtin_ctzll(x.s.high) + (1 + sizeof(di_int) * CHAR_BIT);
+ }
+ return __builtin_ctzll(x.s.low) + 1;
+}
+
+#endif /* CRT_HAS_128BIT */