From ca9211ecdede9bdedb812b2243a4abdb8dacd1b9 Mon Sep 17 00:00:00 2001 From: Dimitry Andric Date: Wed, 7 Jan 2015 19:55:37 +0000 Subject: Import compiler-rt trunk r224034. https://llvm.org/svn/llvm-project/compiler-rt/trunk@224034 --- lib/builtins/clzti2.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 lib/builtins/clzti2.c (limited to 'lib/builtins/clzti2.c') diff --git a/lib/builtins/clzti2.c b/lib/builtins/clzti2.c new file mode 100644 index 0000000000000..15a7b3c900042 --- /dev/null +++ b/lib/builtins/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 */ -- cgit v1.2.3