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#ifndef _ASM_WORD_AT_A_TIME_H
#define _ASM_WORD_AT_A_TIME_H
/*
* Word-at-a-time interfaces for PowerPC.
*/
#include <linux/kernel.h>
#include <asm/asm-compat.h>
#include <asm/extable.h>
#ifdef __BIG_ENDIAN__
struct word_at_a_time {
const unsigned long high_bits, low_bits;
};
#define WORD_AT_A_TIME_CONSTANTS { REPEAT_BYTE(0xfe) + 1, REPEAT_BYTE(0x7f) }
/* Bit set in the bytes that have a zero */
static inline long prep_zero_mask(unsigned long val, unsigned long rhs, const struct word_at_a_time *c)
{
unsigned long mask = (val & c->low_bits) + c->low_bits;
return ~(mask | rhs);
}
#define create_zero_mask(mask) (mask)
static inline long find_zero(unsigned long mask)
{
long leading_zero_bits;
asm (PPC_CNTLZL "%0,%1" : "=r" (leading_zero_bits) : "r" (mask));
return leading_zero_bits >> 3;
}
static inline bool has_zero(unsigned long val, unsigned long *data, const struct word_at_a_time *c)
{
unsigned long rhs = val | c->low_bits;
*data = rhs;
return (val + c->high_bits) & ~rhs;
}
static inline unsigned long zero_bytemask(unsigned long mask)
{
return ~1ul << __fls(mask);
}
#else
#ifdef CONFIG_64BIT
/* unused */
struct word_at_a_time {
};
#define WORD_AT_A_TIME_CONSTANTS { }
/* This will give us 0xff for a NULL char and 0x00 elsewhere */
static inline unsigned long has_zero(unsigned long a, unsigned long *bits, const struct word_at_a_time *c)
{
unsigned long ret;
unsigned long zero = 0;
asm("cmpb %0,%1,%2" : "=r" (ret) : "r" (a), "r" (zero));
*bits = ret;
return ret;
}
static inline unsigned long prep_zero_mask(unsigned long a, unsigned long bits, const struct word_at_a_time *c)
{
return bits;
}
/* Alan Modra's little-endian strlen tail for 64-bit */
static inline unsigned long create_zero_mask(unsigned long bits)
{
unsigned long leading_zero_bits;
long trailing_zero_bit_mask;
asm("addi %1,%2,-1\n\t"
"andc %1,%1,%2\n\t"
"popcntd %0,%1"
: "=r" (leading_zero_bits), "=&r" (trailing_zero_bit_mask)
: "b" (bits));
return leading_zero_bits;
}
static inline unsigned long find_zero(unsigned long mask)
{
return mask >> 3;
}
/* This assumes that we never ask for an all 1s bitmask */
static inline unsigned long zero_bytemask(unsigned long mask)
{
return (1UL << mask) - 1;
}
#else /* 32-bit case */
struct word_at_a_time {
const unsigned long one_bits, high_bits;
};
#define WORD_AT_A_TIME_CONSTANTS { REPEAT_BYTE(0x01), REPEAT_BYTE(0x80) }
/*
* This is largely generic for little-endian machines, but the
* optimal byte mask counting is probably going to be something
* that is architecture-specific. If you have a reliably fast
* bit count instruction, that might be better than the multiply
* and shift, for example.
*/
/* Carl Chatfield / Jan Achrenius G+ version for 32-bit */
static inline long count_masked_bytes(long mask)
{
/* (000000 0000ff 00ffff ffffff) -> ( 1 1 2 3 ) */
long a = (0x0ff0001+mask) >> 23;
/* Fix the 1 for 00 case */
return a & mask;
}
static inline unsigned long create_zero_mask(unsigned long bits)
{
bits = (bits - 1) & ~bits;
return bits >> 7;
}
static inline unsigned long find_zero(unsigned long mask)
{
return count_masked_bytes(mask);
}
/* Return nonzero if it has a zero */
static inline unsigned long has_zero(unsigned long a, unsigned long *bits, const struct word_at_a_time *c)
{
unsigned long mask = ((a - c->one_bits) & ~a) & c->high_bits;
*bits = mask;
return mask;
}
static inline unsigned long prep_zero_mask(unsigned long a, unsigned long bits, const struct word_at_a_time *c)
{
return bits;
}
/* The mask we created is directly usable as a bytemask */
#define zero_bytemask(mask) (mask)
#endif /* CONFIG_64BIT */
#endif /* __BIG_ENDIAN__ */
/*
* We use load_unaligned_zero() in a selftest, which builds a userspace
* program. Some linker scripts seem to discard the .fixup section, so allow
* the test code to use a different section name.
*/
#ifndef FIXUP_SECTION
#define FIXUP_SECTION ".fixup"
#endif
static inline unsigned long load_unaligned_zeropad(const void *addr)
{
unsigned long ret, offset, tmp;
asm(
"1: " PPC_LL "%[ret], 0(%[addr])\n"
"2:\n"
".section " FIXUP_SECTION ",\"ax\"\n"
"3: "
#ifdef __powerpc64__
"clrrdi %[tmp], %[addr], 3\n\t"
"clrlsldi %[offset], %[addr], 61, 3\n\t"
"ld %[ret], 0(%[tmp])\n\t"
#ifdef __BIG_ENDIAN__
"sld %[ret], %[ret], %[offset]\n\t"
#else
"srd %[ret], %[ret], %[offset]\n\t"
#endif
#else
"clrrwi %[tmp], %[addr], 2\n\t"
"clrlslwi %[offset], %[addr], 30, 3\n\t"
"lwz %[ret], 0(%[tmp])\n\t"
#ifdef __BIG_ENDIAN__
"slw %[ret], %[ret], %[offset]\n\t"
#else
"srw %[ret], %[ret], %[offset]\n\t"
#endif
#endif
"b 2b\n"
".previous\n"
EX_TABLE(1b, 3b)
: [tmp] "=&b" (tmp), [offset] "=&r" (offset), [ret] "=&r" (ret)
: [addr] "b" (addr), "m" (*(unsigned long *)addr));
return ret;
}
#undef FIXUP_SECTION
#endif /* _ASM_WORD_AT_A_TIME_H */
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