29 lines
788 B
C
29 lines
788 B
C
|
//===-- clzdi2.c - Implement __clzdi2 -------------------------------------===//
|
||
|
//
|
||
|
// The LLVM Compiler Infrastructure
|
||
|
//
|
||
|
// This file is distributed under the University of Illinois Open Source
|
||
|
// License. See LICENSE.TXT for details.
|
||
|
//
|
||
|
//===----------------------------------------------------------------------===//
|
||
|
//
|
||
|
// This file implements __clzdi2 for the compiler_rt library.
|
||
|
//
|
||
|
//===----------------------------------------------------------------------===//
|
||
|
|
||
|
#include "int_lib.h"
|
||
|
|
||
|
// Returns: the number of leading 0-bits
|
||
|
|
||
|
// Precondition: a != 0
|
||
|
|
||
|
si_int
|
||
|
__clzdi2(di_int a)
|
||
|
{
|
||
|
dwords x;
|
||
|
x.all = a;
|
||
|
const si_int f = -(x.high == 0);
|
||
|
return __builtin_clz((x.high & ~f) | (x.low & f)) +
|
||
|
(f & ((si_int)(sizeof(si_int) * CHAR_BIT)));
|
||
|
}
|