2f89e26ac0
mckernel/lib/include/*.h mckernel/arch/x86/elfboot/* mckernel/arch/x86/kboot/main.c mckernel/arch/x86/kernel/* mckernel/lib/page_alloc.c mckernel/lib/string.c mckernel/lib/include/ihk/* except mckernel/arch/x86/kernel/include/signal.h mckernel/arch/x86/tools/mcreboot-attached-mic.sh.in mckernel/arch/x86/kernel/include/syscall_list.h mckernel/arch/x86/kernel/syscall.c .
28 lines
481 B
C
28 lines
481 B
C
/**
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* \file bitops.h
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* License details are found in the file LICENSE.
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* \brief
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* Find last set bit in word.
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* \author Taku Shimosawa <shimosawa@is.s.u-tokyo.ac.jp> \par
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* Copyright (C) 2011 - 2012 Taku Shimosawa
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*/
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/*
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* HISTORY
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*/
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#ifndef HEADER_X86_COMMON_BITOPS_H
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#define HEADER_X86_COMMON_BITOPS_H
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static inline int fls(int x)
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{
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int r;
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asm("bsrl %1,%0\n\t"
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"jnz 1f\n\t"
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"movl $-1,%0\n"
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"1:" : "=r" (r) : "rm" (x));
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return r + 1;
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}
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#endif
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