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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
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123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140/* tnum: tracked (or tristate) numbers * * A tnum tracks knowledge about the bits of a value. Each bit can be either * known (0 or 1), or unknown (x). Arithmetic operations on tnums will * propagate the unknown bits such that the tnum result represents all the * possible results for possible values of the operands. */
#ifndef _LINUX_TNUM_H#define _LINUX_TNUM_H
#include <linux/types.h>
struct tnum { u64 value; u64 mask;};
/* Constructors *//* Represent a known constant as a tnum. */struct tnum tnum_const(u64 value);/* A completely unknown value */extern const struct tnum tnum_unknown;/* An unknown value that is a superset of @min <= value <= @max. * * Could include values outside the range of [@min, @max]. * For example tnum_range(0, 2) is represented by {0, 1, 2, *3*}, * rather than the intended set of {0, 1, 2}. */struct tnum tnum_range(u64 min, u64 max);
/* Arithmetic and logical ops *//* Shift a tnum left (by a fixed shift) */struct tnum tnum_lshift(struct tnum a, u8 shift);/* Shift (rsh) a tnum right (by a fixed shift) */struct tnum tnum_rshift(struct tnum a, u8 shift);/* Shift (arsh) a tnum right (by a fixed min_shift) */struct tnum tnum_arshift(struct tnum a, u8 min_shift, u8 insn_bitness);/* Add two tnums, return @a + @b */struct tnum tnum_add(struct tnum a, struct tnum b);/* Subtract two tnums, return @a - @b */struct tnum tnum_sub(struct tnum a, struct tnum b);/* Neg of a tnum, return 0 - @a */struct tnum tnum_neg(struct tnum a);/* Bitwise-AND, return @a & @b */struct tnum tnum_and(struct tnum a, struct tnum b);/* Bitwise-OR, return @a | @b */struct tnum tnum_or(struct tnum a, struct tnum b);/* Bitwise-XOR, return @a ^ @b */struct tnum tnum_xor(struct tnum a, struct tnum b);/* Multiply two tnums, return @a * @b */struct tnum tnum_mul(struct tnum a, struct tnum b);
/* Return true if the known bits of both tnums have the same value */bool tnum_overlap(struct tnum a, struct tnum b);
/* Return a tnum representing numbers satisfying both @a and @b */struct tnum tnum_intersect(struct tnum a, struct tnum b);
/* Returns a tnum representing numbers satisfying either @a or @b */struct tnum tnum_union(struct tnum t1, struct tnum t2);
/* Return @a with all but the lowest @size bytes cleared */struct tnum tnum_cast(struct tnum a, u8 size);
/* Swap the bytes of a tnum */struct tnum tnum_bswap16(struct tnum a);struct tnum tnum_bswap32(struct tnum a);struct tnum tnum_bswap64(struct tnum a);
/* Returns true if @a is a known constant */static inline bool tnum_is_const(struct tnum a){ return !a.mask;}
/* Returns true if @a == tnum_const(@b) */static inline bool tnum_equals_const(struct tnum a, u64 b){ return tnum_is_const(a) && a.value == b;}
/* Returns true if @a is completely unknown */static inline bool tnum_is_unknown(struct tnum a){ return !~a.mask;}
/* Returns true if @a is known to be a multiple of @size. * @size must be a power of two. */bool tnum_is_aligned(struct tnum a, u64 size);
/* Returns true if @b represents a subset of @a. * * Note that using tnum_range() as @a requires extra cautions as tnum_in() may * return true unexpectedly due to tnum limited ability to represent tight * range, e.g. * * tnum_in(tnum_range(0, 2), tnum_const(3)) == true * * As a rule of thumb, if @a is explicitly coded rather than coming from * reg->var_off, it should be in form of tnum_const(), tnum_range(0, 2**n - 1), * or tnum_range(2**n, 2**(n+1) - 1). */bool tnum_in(struct tnum a, struct tnum b);
/* Formatting functions. These have snprintf-like semantics: they will write * up to @size bytes (including the terminating NUL byte), and return the number * of bytes (excluding the terminating NUL) which would have been written had * sufficient space been available. (Thus tnum_sbin always returns 64.) *//* Format a tnum as a pair of hex numbers (value; mask) */int tnum_strn(char *str, size_t size, struct tnum a);/* Format a tnum as tristate binary expansion */int tnum_sbin(char *str, size_t size, struct tnum a);
/* Returns the 32-bit subreg */struct tnum tnum_subreg(struct tnum a);/* Returns the tnum with the lower 32-bit subreg cleared */struct tnum tnum_clear_subreg(struct tnum a);/* Returns the tnum with the lower 32-bit subreg in *reg* set to the lower * 32-bit subreg in *subreg* */struct tnum tnum_with_subreg(struct tnum reg, struct tnum subreg);/* Returns the tnum with the lower 32-bit subreg set to value */struct tnum tnum_const_subreg(struct tnum a, u32 value);/* Returns true if 32-bit subreg @a is a known constant*/static inline bool tnum_subreg_is_const(struct tnum a){ return !(tnum_subreg(a)).mask;}
/* Returns the smallest member of t larger than z */u64 tnum_step(struct tnum t, u64 z);
u32 tnum_alignment(struct tnum a);
#endif /* _LINUX_TNUM_H */