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Release 4.14 arch/sh/include/asm/bitops-op32.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_SH_BITOPS_OP32_H

#define __ASM_SH_BITOPS_OP32_H

/*
 * The bit modifying instructions on SH-2A are only capable of working
 * with a 3-bit immediate, which signifies the shift position for the bit
 * being worked on.
 */
#if defined(__BIG_ENDIAN)

#define BITOP_LE_SWIZZLE	((BITS_PER_LONG-1) & ~0x7)

#define BYTE_NUMBER(nr)		((nr ^ BITOP_LE_SWIZZLE) / BITS_PER_BYTE)

#define BYTE_OFFSET(nr)		((nr ^ BITOP_LE_SWIZZLE) % BITS_PER_BYTE)
#else

#define BYTE_NUMBER(nr)		((nr) / BITS_PER_BYTE)

#define BYTE_OFFSET(nr)		((nr) % BITS_PER_BYTE)
#endif


#define IS_IMMEDIATE(nr)	(__builtin_constant_p(nr))


static inline void __set_bit(int nr, volatile unsigned long *addr) { if (IS_IMMEDIATE(nr)) { __asm__ __volatile__ ( "bset.b %1, @(%O2,%0) ! __set_bit\n\t" : "+r" (addr) : "i" (BYTE_OFFSET(nr)), "i" (BYTE_NUMBER(nr)) : "t", "memory" ); } else { unsigned long mask = BIT_MASK(nr); unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); *p |= mask; } }

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static inline void __clear_bit(int nr, volatile unsigned long *addr) { if (IS_IMMEDIATE(nr)) { __asm__ __volatile__ ( "bclr.b %1, @(%O2,%0) ! __clear_bit\n\t" : "+r" (addr) : "i" (BYTE_OFFSET(nr)), "i" (BYTE_NUMBER(nr)) : "t", "memory" ); } else { unsigned long mask = BIT_MASK(nr); unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); *p &= ~mask; } }

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/** * __change_bit - Toggle a bit in memory * @nr: the bit to change * @addr: the address to start counting from * * Unlike change_bit(), this function is non-atomic and may be reordered. * If it's called on the same region of memory simultaneously, the effect * may be that only one operation succeeds. */
static inline void __change_bit(int nr, volatile unsigned long *addr) { if (IS_IMMEDIATE(nr)) { __asm__ __volatile__ ( "bxor.b %1, @(%O2,%0) ! __change_bit\n\t" : "+r" (addr) : "i" (BYTE_OFFSET(nr)), "i" (BYTE_NUMBER(nr)) : "t", "memory" ); } else { unsigned long mask = BIT_MASK(nr); unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); *p ^= mask; } }

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Paul Mundt64100.00%1100.00%
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/** * __test_and_set_bit - Set a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is non-atomic and can be reordered. * If two examples of this operation race, one can appear to succeed * but actually fail. You must protect multiple accesses with a lock. */
static inline int __test_and_set_bit(int nr, volatile unsigned long *addr) { unsigned long mask = BIT_MASK(nr); unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); unsigned long old = *p; *p = old | mask; return (old & mask) != 0; }

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/** * __test_and_clear_bit - Clear a bit and return its old value * @nr: Bit to clear * @addr: Address to count from * * This operation is non-atomic and can be reordered. * If two examples of this operation race, one can appear to succeed * but actually fail. You must protect multiple accesses with a lock. */
static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr) { unsigned long mask = BIT_MASK(nr); unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); unsigned long old = *p; *p = old & ~mask; return (old & mask) != 0; }

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Paul Mundt68100.00%1100.00%
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/* WARNING: non atomic and it can be reordered! */
static inline int __test_and_change_bit(int nr, volatile unsigned long *addr) { unsigned long mask = BIT_MASK(nr); unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); unsigned long old = *p; *p = old ^ mask; return (old & mask) != 0; }

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Paul Mundt67100.00%1100.00%
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/** * test_bit - Determine whether a bit is set * @nr: bit number to test * @addr: Address to start counting from */
static inline int test_bit(int nr, const volatile unsigned long *addr) { return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1))); }

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#endif /* __ASM_SH_BITOPS_OP32_H */

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Greg Kroah-Hartman10.20%150.00%
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