%---------------------------------------------------------------------------% % vim: ts=4 sw=4 et ft=mercury %---------------------------------------------------------------------------% % Copyright (C) 2018-2021 The Mercury team. % This file is distributed under the terms specified in COPYING.LIB. %---------------------------------------------------------------------------% % % File: uint64.m % Main author: juliensf % Stability: low. % % Predicates and functions for dealing with unsigned 64-bit integer numbers. % %---------------------------------------------------------------------------% :- module uint64. :- interface. :- import_module pretty_printer. %---------------------------------------------------------------------------% % % Conversion from int. % % from_int(I, U64): % % Convert an int into a uint64. % Fails if I is not in [0, 2^64 - 1]. % :- pred from_int(int::in, uint64::out) is semidet. % det_from_int(I) = U64: % % Convert an int into a uint64. % Throws an exception if I is not in [0, 2^64 - 1]. % :- func det_from_int(int) = uint64. % cast_from_int(I) = U64: % % Convert an int to a uint64. % Always succeeds, but will yield a result that is mathematically equal % to I only if I is in [0, 2^64 - 1]. % :- func cast_from_int(int) = uint64. %---------------------------------------------------------------------------% % % Conversion from uint. % % cast_from_uint(U) = U64: % % Convert a uint to a uint64. % Always succeeds, and will always yield a result that is % mathematically equal U. % :- func cast_from_uint(uint) = uint64. %---------------------------------------------------------------------------% % % Conversion to int. % % cast_to_int(U64) = I: % % Convert a uint64 to an int. % Always succeeds. If ints are 64 bits, I will be mathematically % equal to U64 only if U64 is in [0, 2^63 - 1]. If ints are 32 % bits, I will be mathematically equal to U64 only if U64 is in % [0, 2^31 - 1]. % :- func cast_to_int(uint64) = int. %---------------------------------------------------------------------------% % % Conversion to uint. % % cast_to_uint(U64) = U: % % Convert a uint64 to a uint. % Always succeeds, but will yield a result that is mathematically equal % to U64 only if uints are 64 bits. % :- func cast_to_uint(uint64) = uint. %---------------------------------------------------------------------------% % % Conversion to/from uint8 % % cast_to_uint8(U64) = U8: % % Convert a uint64 to a uint8. % Always succeeds, but will yield a result that is mathematically equal % to U64 only if U64 is in [0, 2^8 - 1]. % :- func cast_to_uint8(uint64) = uint8. % cast_from_uint8(U8) = U64: % % Convert a uint8 to a uint64. % Always succeeds, and yields a result that is mathematically equal % to U8. % :- func cast_from_uint8(uint8) = uint64. %---------------------------------------------------------------------------% % % Change of signedness. % % cast_from_int64(I64) = U64: % % Convert an int64 to a uint64. This will yield a result that is % mathematically equal to I64 only if I64 is in [0, 2^63 - 1]. % :- func cast_from_int64(int64) = uint64. %---------------------------------------------------------------------------% % % Conversion from byte sequence. % % from_bytes_le(Byte0, Byte1, ..., Byte7) = U64: % % U64 is the uint64 whose bytes are given in little-endian order by the % arguments from left-to-right (i.e. Byte0 is the least significant byte % and Byte7 is the most significant byte). % :- func from_bytes_le(uint8, uint8, uint8, uint8, uint8, uint8, uint8, uint8) = uint64. % from_bytes_be(Byte0, Byte1, ..., Byte7) = U64: % % U64 is the uint64 whose bytes are given in big-endian order by the % arguments in left-to-right order (i.e. Byte0 is the most significant % byte and Byte7 is the least significant byte). % :- func from_bytes_be(uint8, uint8, uint8, uint8, uint8, uint8, uint8, uint8) = uint64. %---------------------------------------------------------------------------% % % Comparisons and related operations. % % Less than. % :- pred (uint64::in) < (uint64::in) is semidet. % Greater than. % :- pred (uint64::in) > (uint64::in) is semidet. % Less than or equal. % :- pred (uint64::in) =< (uint64::in) is semidet. % Greater than or equal. % :- pred (uint64::in) >= (uint64::in) is semidet. % Maximum. % :- func max(uint64, uint64) = uint64. % Minimum. % :- func min(uint64, uint64) = uint64. %---------------------------------------------------------------------------% % % Arithmetic operations. % % Addition. % :- func uint64 + uint64 = uint64. :- mode in + in = uo is det. :- mode uo + in = in is det. :- mode in + uo = in is det. :- func plus(uint64, uint64) = uint64. % Subtraction. % :- func uint64 - uint64 = uint64. :- mode in - in = uo is det. :- mode uo - in = in is det. :- mode in - uo = in is det. :- func minus(uint64, uint64) = uint64. % Multiplication. % :- func (uint64::in) * (uint64::in) = (uint64::uo) is det. :- func times(uint64, uint64) = uint64. % Truncating integer division. % % Throws a `domain_error' exception if the right operand is zero. % :- func (uint64::in) div (uint64::in) = (uint64::uo) is det. % Truncating integer division. % % Throws a `domain_error' exception if the right operand is zero. % :- func (uint64::in) // (uint64::in) = (uint64::uo) is det. % (/)/2 is a synonym for (//)/2. % :- func (uint64::in) / (uint64::in) = (uint64::uo) is det. % unchecked_quotient(X, Y) is the same as X // Y, but the behaviour % is undefined if the right operand is zero. % :- func unchecked_quotient(uint64::in, uint64::in) = (uint64::uo) is det. % Modulus. % X mod Y = X - (X div Y) * Y % % Throws a `domain_error' exception if the right operand is zero. % :- func (uint64::in) mod (uint64::in) = (uint64::uo) is det. % Remainder. % X rem Y = X - (X // Y) * Y. % % Throws a `domain_error/` exception if the right operand is zero. % :- func (uint64::in) rem (uint64::in) = (uint64::uo) is det. % unchecked_rem(X, Y) is the same as X rem Y, but the behaviour is % undefined if the right operand is zero. % :- func unchecked_rem(uint64::in, uint64::in) = (uint64::uo) is det. % even(X) is equivalent to (X mod 2 = 0). % :- pred even(uint64::in) is semidet. % odd(X) is equivalent to (not even(X)), i.e. (X mod 2 = 1). % :- pred odd(uint64::in) is semidet. %---------------------------------------------------------------------------% % % Shift operations. % % Left shift. % X << Y returns X "left shifted" by Y bits. % The bit positions vacated by the shift are filled by zeros. % Throws an exception if Y is not in [0, 64). % :- func (uint64::in) << (int::in) = (uint64::uo) is det. :- func (uint64::in) <> Y returns X "right shifted" by Y bits. % The bit positions vacated by the shift are filled by zeros. % Throws an exception if Y is not in [0, 64). % :- func (uint64::in) >> (int::in) = (uint64::uo) is det. :- func (uint64::in) >>u (uint::in) = (uint64::uo) is det. % unchecked_right_shift(X, Y) is the same as X >> Y except that % the behaviour is undefined if Y is not in [0, 64). % It will typically be implemented more efficiently than X >> Y. % :- func unchecked_right_shift(uint64::in, int::in) = (uint64::uo) is det. :- func unchecked_right_ushift(uint64::in, uint::in) = (uint64::uo) is det. %---------------------------------------------------------------------------% % % Logical operations. % % Bitwise and. % :- func (uint64::in) /\ (uint64::in) = (uint64::uo) is det. % Bitwise or. % :- func (uint64::in) \/ (uint64::in) = (uint64::uo) is det. % Bitwise exclusive or (xor). % :- func xor(uint64, uint64) = uint64. :- mode xor(in, in) = uo is det. :- mode xor(in, uo) = in is det. :- mode xor(uo, in) = in is det. % Bitwise complement. % :- func \ (uint64::in) = (uint64::uo) is det. %---------------------------------------------------------------------------% % % Operations on bits and bytes. % % num_zeros(U) = N: % % N is the number of zeros in the binary representation of U. % :- func num_zeros(uint64) = int. % num_ones(U) = N: % % N is the number of ones in the binary representation of U. % :- func num_ones(uint64) = int. % num_leading_zeros(U) = N: % % N is the number of leading zeros in the binary representation of U. % :- func num_leading_zeros(uint64) = int. % num_trailing_zeros(U) = N: % N is the number of trailing zeros in the binary representation of U. % :- func num_trailing_zeros(uint64) = int. % reverse_bytes(A) = B: % % B is the value that results from reversing the bytes in the binary % representation of A. % :- func reverse_bytes(uint64) = uint64. % reverse_bits(A) = B: % % B is the is value that results from reversing the bits % in the binary representation of A. % :- func reverse_bits(uint64) = uint64. % rotate_left(U, D) = N: % % N is the value obtained by rotating the binary representation of U % left by D bits. Throws an exception if D is not in the range [0, 63]. % :- func rotate_left(uint64, uint) = uint64. % unchecked_rotate_left(U, D) = N: % % N is the value obtained by rotating the binary representation of U % left by an amount given by the lowest 6 bits of D. % :- func unchecked_rotate_left(uint64, uint) = uint64. % rotate_right(U, D) = N: % % N is the value obtained by rotating the binary representation of U % right by D bits. Throws an exception if D is not in the range [0, 63]. % :- func rotate_right(uint64, uint) = uint64. % unchecked_rotate_left(U, D) = N: % % N is the value obtained by rotating the binary representation of U % right by an amount given by the lowest 6 bits of D. % :- func unchecked_rotate_right(uint64, uint) = uint64. % set_bit(U, I) = N: % N is the value obtained by setting the I'th bit (the bit worth 2^I) of U % to one. An exception is thrown if I is not in the range [0, 63]. % :- func set_bit(uint64, uint) = uint64. % unchecked_set_bit(U, I) = N: % As above, but the behaviour is undefined if I is not in the range % [0, 63]. % :- func unchecked_set_bit(uint64, uint) = uint64. % clear_bit(U, I) = N: % N is the value obtained by setting the I'th bit (the bit worth 2^I) of U % to zero. An exception is thrown if I is not in the range [0, 63]. % :- func clear_bit(uint64, uint) = uint64. % unchecked_clear_bit(U, I) = N: % As above, but the behaviour is undefined if I is not in the range % [0, 63]. % :- func unchecked_clear_bit(uint64, uint) = uint64. % flip_bit(U, I) = N: % N is the value obtained by flipping the I'th bit (the bit worth 2^I) of % U. An exception is thrown if I is not in the range [0, 63]. % :- func flip_bit(uint64, uint) = uint64. % unchecked_flip_bit(U, I) = N: % As above, but the behaviour is undefined if I is not in the range % [0, 63]. % :- func unchecked_flip_bit(uint64, uint) = uint64. % bit_is_set(U, I): % True iff the I'th bit (the bit worth 2^I) of U is one. % An exception is thrown if I is not in the range [0, 63]. % :- pred bit_is_set(uint64::in, uint::in) is semidet. % unchecked_bit_is_set(U, I): % As above, but the behaviour is undefined if I is not in the range % [0, 63]. % :- pred unchecked_bit_is_set(uint64::in, uint::in) is semidet. % bit_is_clear(U, I): % True iff the I'th bit (the bit worth 2^I) of U is zero. % An exception is thrown if I is not in the range [0, 63]. % :- pred bit_is_clear(uint64::in, uint::in) is semidet. % unchecked_bit_is_clear(U, I): % As above, but the behaviour is undefined if I is not in the range % [0, 63]. % :- pred unchecked_bit_is_clear(uint64::in, uint::in) is semidet. %---------------------------------------------------------------------------% % % Limits. % :- func max_uint64 = uint64. %---------------------------------------------------------------------------% % % Prettyprinting. % % Convert a uint64 to a pretty_printer.doc for formatting. % :- func uint64_to_doc(uint64) = pretty_printer.doc. :- pragma obsolete(func(uint64_to_doc/1), [pretty_printer.uint64_to_doc/1]). %---------------------------------------------------------------------------% %---------------------------------------------------------------------------% :- implementation. :- import_module exception. :- import_module int. :- import_module require. :- import_module uint. %---------------------------------------------------------------------------% :- pragma foreign_proc("C", from_int(I::in, U64::out), [will_not_call_mercury, promise_pure, thread_safe, will_not_modify_trail], " if (I < 0) { SUCCESS_INDICATOR = MR_FALSE; } else if ((uint64_t) I > (uint64_t) INT64_MAX) { SUCCESS_INDICATOR = MR_FALSE; } else { U64 = (uint64_t) I; SUCCESS_INDICATOR = MR_TRUE; } "). :- pragma foreign_proc("C#", from_int(I::in, U64::out), [will_not_call_mercury, promise_pure, thread_safe], " U64 = (ulong) I; SUCCESS_INDICATOR = (I < 0) ? false : true; "). :- pragma foreign_proc("Java", from_int(I::in, U64::out), [will_not_call_mercury, promise_pure, thread_safe], " U64 = I; SUCCESS_INDICATOR = (I < 0) ? false : true; "). det_from_int(I) = U64 :- ( if from_int(I, U64Prime) then U64 = U64Prime else error($pred, "cannot convert int to uint64") ). :- pragma foreign_proc("C", cast_from_int(I::in) = (U64::out), [will_not_call_mercury, promise_pure, thread_safe, will_not_modify_trail, does_not_affect_liveness], " U64 = (uint64_t) I; "). :- pragma foreign_proc("C#", cast_from_int(I::in) = (U64::out), [will_not_call_mercury, promise_pure, thread_safe], " U64 = (ulong) I; "). :- pragma foreign_proc("Java", cast_from_int(I::in) = (U64::out), [will_not_call_mercury, promise_pure, thread_safe], " U64 = I; "). %---------------------------------------------------------------------------% :- pragma foreign_proc("C", cast_from_uint(U::in) = (U64::out), [will_not_call_mercury, promise_pure, thread_safe, will_not_modify_trail, does_not_affect_liveness], " U64 = (uint64_t) U; "). :- pragma foreign_proc("C#", cast_from_uint(U::in) = (U64::out), [will_not_call_mercury, promise_pure, thread_safe], " U64 = (ulong) U; "). :- pragma foreign_proc("Java", cast_from_uint(U::in) = (U64::out), [will_not_call_mercury, promise_pure, thread_safe], " U64 = (long) U & 0xffffffffL; "). %---------------------------------------------------------------------------% :- pragma foreign_proc("C", cast_to_int(U64::in) = (I::out), [will_not_call_mercury, promise_pure, thread_safe, will_not_modify_trail, does_not_affect_liveness], " I = (MR_Integer) U64; "). :- pragma foreign_proc("C#", cast_to_int(U64::in) = (I::out), [will_not_call_mercury, promise_pure, thread_safe], " I = (int) U64; "). :- pragma foreign_proc("Java", cast_to_int(U64::in) = (I::out), [will_not_call_mercury, promise_pure, thread_safe], " I = (int) U64; "). %---------------------------------------------------------------------------% :- pragma foreign_proc("C", cast_to_uint(U64::in) = (U::out), [will_not_call_mercury, promise_pure, thread_safe, will_not_modify_trail, does_not_affect_liveness], " U = (MR_Unsigned) U64; "). :- pragma foreign_proc("C#", cast_to_uint(U64::in) = (U::out), [will_not_call_mercury, promise_pure, thread_safe], " U = (uint) U64; "). :- pragma foreign_proc("Java", cast_to_uint(U64::in) = (U::out), [will_not_call_mercury, promise_pure, thread_safe], " U = (int) U64; "). %---------------------------------------------------------------------------% :- pragma foreign_proc("C", cast_to_uint8(U64::in) = (U8::out), [will_not_call_mercury, promise_pure, thread_safe, will_not_modify_trail, does_not_affect_liveness], " U8 = (uint8_t) U64; "). :- pragma foreign_proc("C#", cast_to_uint8(U64::in) = (U8::out), [will_not_call_mercury, promise_pure, thread_safe], " U8 = (byte) U64; "). :- pragma foreign_proc("Java", cast_to_uint8(U64::in) = (U8::out), [will_not_call_mercury, promise_pure, thread_safe], " U8 = (byte) U64; "). %---------------------------------------------------------------------------% :- pragma foreign_proc("C", cast_from_uint8(U8::in) = (U64::out), [will_not_call_mercury, promise_pure, thread_safe, will_not_modify_trail, does_not_affect_liveness], " U64 = (uint64_t) U8; "). :- pragma foreign_proc("C#", cast_from_uint8(U8::in) = (U64::out), [will_not_call_mercury, promise_pure, thread_safe], " U64 = (ulong) U8; "). :- pragma foreign_proc("Java", cast_from_uint8(U8::in) = (U64::out), [will_not_call_mercury, promise_pure, thread_safe], " U64 = (long) (U8 & 0xff); "). %---------------------------------------------------------------------------% :- pragma foreign_proc("C", cast_from_int64(I64::in) = (U64::out), [will_not_call_mercury, promise_pure, thread_safe, will_not_modify_trail, does_not_affect_liveness], " U64 = (uint64_t) I64; "). :- pragma foreign_proc("C#", cast_from_int64(I64::in) = (U64::out), [will_not_call_mercury, promise_pure, thread_safe], " U64 = (ulong) I64; "). :- pragma foreign_proc("Java", cast_from_int64(I64::in) = (U64::out), [will_not_call_mercury, promise_pure, thread_safe], " U64 = I64; "). %---------------------------------------------------------------------------% :- pragma foreign_proc("C", from_bytes_le(Byte0::in, Byte1::in, Byte2::in, Byte3::in, Byte4::in, Byte5::in, Byte6::in, Byte7::in) = (U64::out), [will_not_call_mercury, promise_pure, thread_safe, will_not_modify_trail], " unsigned char *uint64_bytes = (unsigned char *) &U64; #if defined(MR_BIG_ENDIAN) uint64_bytes[0] = Byte7; uint64_bytes[1] = Byte6; uint64_bytes[2] = Byte5; uint64_bytes[3] = Byte4; uint64_bytes[4] = Byte3; uint64_bytes[5] = Byte2; uint64_bytes[6] = Byte1; uint64_bytes[7] = Byte0; #else uint64_bytes[0] = Byte0; uint64_bytes[1] = Byte1; uint64_bytes[2] = Byte2; uint64_bytes[3] = Byte3; uint64_bytes[4] = Byte4; uint64_bytes[5] = Byte5; uint64_bytes[6] = Byte6; uint64_bytes[7] = Byte7; #endif "). :- pragma foreign_proc("Java", from_bytes_le(Byte0::in, Byte1::in, Byte2::in, Byte3::in, Byte4::in, Byte5::in, Byte6::in, Byte7::in) = (U64::out), [will_not_call_mercury, promise_pure, thread_safe], " U64 = (long) (Byte7 & 0xff) << 56 | (long) (Byte6 & 0xff) << 48 | (long) (Byte5 & 0xff) << 40 | (long) (Byte4 & 0xff) << 32 | (long) (Byte3 & 0xff) << 24 | (long) (Byte2 & 0xff) << 16 | (long) (Byte1 & 0xff) << 8 | (long) (Byte0 & 0xff); "). :- pragma foreign_proc("C#", from_bytes_le(Byte0::in, Byte1::in, Byte2::in, Byte3::in, Byte4::in, Byte5::in, Byte6::in, Byte7::in) = (U64::out), [will_not_call_mercury, promise_pure, thread_safe], " U64 = (ulong) ( (ulong) Byte7 << 56 | (ulong) Byte6 << 48 | (ulong) Byte5 << 40 | (ulong) Byte4 << 32 | (ulong) Byte3 << 24 | (ulong) Byte2 << 16 | (ulong) Byte1 << 8 | (ulong) Byte0); "). from_bytes_be(Byte7, Byte6, Byte5,Byte4, Byte3, Byte2, Byte1, Byte0) = from_bytes_le(Byte0, Byte1, Byte2, Byte3, Byte4, Byte5, Byte6, Byte7). %---------------------------------------------------------------------------% % The comparison operations <, >, =< and >= are builtins. max(X, Y) = ( if X > Y then X else Y ). min(X, Y) = ( if X < Y then X else Y ). %---------------------------------------------------------------------------% % The operations +, -, plus, minus, *, and times are builtins. X div Y = X // Y. :- pragma inline(func('//'/2)). X // Y = Div :- ( if Y = 0u64 then throw(domain_error("uint64.'//': division by zero")) else Div = unchecked_quotient(X, Y) ). :- pragma inline(func('/'/2)). X / Y = X // Y. % The operations unchecked_quotient and unchecked_rem are builtins. X mod Y = X rem Y. :- pragma inline(func(rem/2)). X rem Y = Rem :- ( if Y = 0u64 then throw(domain_error("uint64.rem: division by zero")) else Rem = unchecked_rem(X, Y) ). :- pragma inline(pred(even/1)). even(X) :- (X /\ 1u64) = 0u64. :- pragma inline(pred(odd/1)). odd(X) :- (X /\ 1u64) \= 0u64. %---------------------------------------------------------------------------% % The unchecked shift operations are builtins. X << Y = Result :- ( if cast_from_int(Y) < 64u then Result = unchecked_left_shift(X, Y) else Msg = "uint64.(<<): second operand is out of range", throw(domain_error(Msg)) ). X <> Y = Result :- ( if cast_from_int(Y) < 64u then Result = unchecked_right_shift(X, Y) else Msg = "uint64.(>>): second operand is out of range", throw(domain_error(Msg)) ). X >>u Y = Result :- ( if Y < 64u then Result = unchecked_right_ushift(X, Y) else Msg = "uint64.(>>u): second operand is out of range", throw(domain_error(Msg)) ). %---------------------------------------------------------------------------% % The algorithms in this section are adapted from chapter 5 of % ``Hacker's Delight'' by Henry S. Warren, Jr. num_zeros(U) = 64 - num_ones(U). :- pragma foreign_proc("C", num_ones(U::in) = (N::out), [will_not_call_mercury, promise_pure, thread_safe, will_not_modify_trail], " #if (defined(MR_GNUC) || defined(MR_CLANG)) && defined(MR_LONG_IS_64_BIT) N = __builtin_popcountl(U); #else U = U - ((U >> 1) & UINT64_C(0x5555555555555555)); U = (U & UINT64_C(0x3333333333333333)) + ((U >> 2) & UINT64_C(0x3333333333333333)); U = (U + (U >> 4)) & UINT64_C(0x0f0f0f0f0f0f0f0f); U = U + (U >> 8); U = U + (U >> 16); U = U + (U >> 32); N = U & UINT64_C(0x7f); #endif "). :- pragma foreign_proc("C#", num_ones(U::in) = (N::out), [will_not_call_mercury, promise_pure, thread_safe], " U = U - ((U >> 1) & 0x5555555555555555UL); U = (U & 0x3333333333333333UL) + ((U >> 2) & 0x3333333333333333UL); U = (U + (U >> 4)) & 0x0f0f0f0f0f0f0f0fUL; U = U + (U >> 8); U = U + (U >> 16); U = U + (U >> 32); N = (int) (U & 0x7fUL); "). :- pragma foreign_proc("Java", num_ones(U::in) = (N::out), [will_not_call_mercury, promise_pure, thread_safe], " N = java.lang.Long.bitCount(U); "). %---------------------% :- pragma foreign_proc("C", num_leading_zeros(U::in) = (N::out), [will_not_call_mercury, promise_pure, thread_safe, will_not_modify_trail], " if (U == 0) { N = 64; } else { int32_t n = 1; uint32_t x = (uint32_t) (U >> 32); if (x == 0) { n += 32; x = (uint32_t) U; } if (x >> 16 == 0) { n += 16; x <<= 16; } if (x >> 24 == 0) { n += 8; x <<= 8; } if (x >> 28 == 0) { n += 4; x <<= 4; } if (x >> 30 == 0) { n += 2; x <<= 2; } N = n - (x >> 31); } "). :- pragma foreign_proc("C#", num_leading_zeros(U::in) = (N::out), [will_not_call_mercury, promise_pure, thread_safe], " if (U == 0) { N = 64; } else { int n = 1; uint x = (uint) (U >> 32); if (x == 0) { n += 32; x = (uint) U; } if (x >> 16 == 0) { n += 16; x <<= 16; } if (x >> 24 == 0) { n += 8; x <<= 8; } if (x >> 28 == 0) { n += 4; x <<= 4; } if (x >> 30 == 0) { n += 2; x <<= 2; } N = n - (int) (x >> 31); } "). :- pragma foreign_proc("Java", num_leading_zeros(U::in) = (N::out), [will_not_call_mercury, promise_pure, thread_safe], " N = java.lang.Long.numberOfLeadingZeros(U); "). %---------------------% :- pragma foreign_proc("C", num_trailing_zeros(U::in) = (N::out), [will_not_call_mercury, promise_pure, thread_safe, will_not_modify_trail], " if (U == 0) { N = 64; } else { uint32_t x, y; int n = 63; y = (int32_t) U; if (y != 0) { n -= 32; x = y; } else { x = (uint32_t) (U >> 32); } y = x << 16; if (y != 0) { n -= 16; x = y; } y = x << 8; if (y != 0) { n -= 8; x = y; } y = x << 4; if (y != 0) { n -= 4; x = y; } y = x << 2; if (y != 0) { n -= 2; x = y; } N = n - (int) ((x << 1) >> 31); } "). :- pragma foreign_proc("C#", num_trailing_zeros(U::in) = (N::out), [will_not_call_mercury, promise_pure, thread_safe], " if (U == 0) { N = 64; } else { uint x, y; int n = 63; y = (uint) U; if (y != 0) { n = n - 32; x = y; } else { x = (uint) (U >> 32); } y = x << 16; if (y != 0) { n = n -16; x = y; } y = x << 8; if (y != 0) { n = n - 8; x = y; } y = x << 4; if (y != 0) { n = n - 4; x = y; } y = x << 2; if (y != 0) { n = n - 2; x = y; } N = n - (int) ((x << 1) >> 31); } "). :- pragma foreign_proc("Java", num_trailing_zeros(U::in) = (N::out), [will_not_call_mercury, promise_pure, thread_safe], " N = java.lang.Long.numberOfTrailingZeros(U); "). %---------------------% :- pragma foreign_proc("C", reverse_bytes(A::in) = (B::out), [will_not_call_mercury, promise_pure, thread_safe, will_not_modify_trail], " B = MR_uint64_reverse_bytes(A); "). :- pragma foreign_proc("Java", reverse_bytes(A::in) = (B::out), [will_not_call_mercury, promise_pure, thread_safe], " B = java.lang.Long.reverseBytes(A); "). reverse_bytes(A) = B :- B = ((A /\ 0x_0000_0000_0000_00ff_u64) << 56) \/ ((A /\ 0x_0000_0000_0000_ff00_u64) << 40) \/ ((A /\ 0x_0000_0000_00ff_0000_u64) << 24) \/ ((A /\ 0x_0000_0000_ff00_0000_u64) << 8) \/ ((A /\ 0x_0000_00ff_0000_0000_u64) >> 8) \/ ((A /\ 0x_0000_ff00_0000_0000_u64) >> 24) \/ ((A /\ 0x_00ff_0000_0000_0000_u64) >> 40) \/ ((A /\ 0x_ff00_0000_0000_0000_u64) >> 56). %---------------------% :- pragma foreign_proc("Java", reverse_bits(A::in) = (B::out), [will_not_call_mercury, promise_pure, thread_safe], " B = java.lang.Long.reverse(A); "). reverse_bits(!.A) = B :- !:A = ((!.A /\ 0x_5555_5555_5555_5555_u64) << 1) \/ ((!.A >> 1) /\ 0x_5555_5555_5555_5555_u64), !:A = ((!.A /\ 0x_3333_3333_3333_3333_u64) << 2) \/ ((!.A >> 2) /\ 0x_3333_3333_3333_3333_u64), !:A = ((!.A /\ 0x_0f0f_0f0f_0f0f_0f0f_u64) << 4) \/ ((!.A >> 4) /\ 0x_0f0f_0f0f_0f0f_0f0f_u64), !:A = ((!.A /\ 0x_00ff_00ff_00ff_00ff_u64) << 8) \/ ((!.A >> 8) /\ 0x_00ff_00ff_00ff_00ff_u64), !:A = (!.A << 48) \/ ((!.A /\ 0x_ffff_0000_u64) << 16) \/ ((!.A >> 16) /\ 0x_ffff_0000_u64) \/ (!.A >> 48), B = !.A. %---------------------------------------------------------------------------% rotate_left(X, N) = ( if N < 64u then unchecked_rotate_left(X, N) else func_error($pred, "rotate amount exceeds 63 bits") ). :- pragma foreign_proc("C", unchecked_rotate_left(X::in, N::in) = (Result::out), [will_not_call_mercury, promise_pure, thread_safe], " N &= 63; // XXX clang has intrinsics for rotation -- we should use those instead. Result = (X << N) | (X >> (-N & 63)); "). :- pragma foreign_proc("C#", unchecked_rotate_left(X::in, N::in) = (Result::out), [will_not_call_mercury, promise_pure, thread_safe], " N &= 63; Result = (X << (int) N) | (X >> (int) (-N & 63)); "). :- pragma foreign_proc("Java", unchecked_rotate_left(X::in, N::in) = (Result::out), [will_not_call_mercury, promise_pure, thread_safe], " Result = java.lang.Long.rotateLeft(X, N); "). %---------------------------------------------------------------------------% rotate_right(X, N) = ( if N < 64u then unchecked_rotate_right(X, N) else func_error($pred, "rotate amount exceeds 63 bits") ). :- pragma foreign_proc("C", unchecked_rotate_right(X::in, N::in) = (Result::out), [will_not_call_mercury, promise_pure, thread_safe], " N &= 63; Result = (X >> N) | (X << (-N & 63)); "). :- pragma foreign_proc("C#", unchecked_rotate_right(X::in, N::in) = (Result::out), [will_not_call_mercury, promise_pure, thread_safe], " N &= 63; Result = (X >> (int) N) | (X << (int) (-N & 63)); "). :- pragma foreign_proc("Java", unchecked_rotate_right(X::in, N::in) = (Result::out), [will_not_call_mercury, promise_pure, thread_safe], " Result = java.lang.Long.rotateRight(X, N); "). %---------------------------------------------------------------------------% set_bit(U, I) = ( if I < 64u then unchecked_set_bit(U, I) else func_error($pred, "bit index exceeds 63 bits") ). unchecked_set_bit(U, I) = U \/ (1u64 `unchecked_left_shift` cast_to_int(I)). clear_bit(U, I) = ( if I < 64u then unchecked_clear_bit(U, I) else func_error($pred, "bit index exceeds 63 bits") ). unchecked_clear_bit(U, I) = U /\ (\ (1u64 `unchecked_left_shift` cast_to_int(I))). flip_bit(U, I) = ( if I < 64u then unchecked_flip_bit(U, I) else func_error($pred, "bit index exceeds 63 bits") ). unchecked_flip_bit(U, I) = U `xor` (1u64 `unchecked_left_shift` cast_to_int(I)). bit_is_set(U, I) :- ( if I < 64u then unchecked_bit_is_set(U, I) else error($pred, "bit index exceeds 63 bits") ). unchecked_bit_is_set(U, I) :- U /\ (1u64 `unchecked_left_shift` cast_to_int(I)) \= 0u64. bit_is_clear(U, I) :- ( if I < 64u then unchecked_bit_is_clear(U, I) else error($pred, "bit index exceeds 63 bits") ). unchecked_bit_is_clear(U, I) :- U /\ (1u64 `unchecked_left_shift` cast_to_int(I)) = 0u64. %---------------------------------------------------------------------------% max_uint64 = 18_446_744_073_709_551_615_u64. %---------------------------------------------------------------------------% uint64_to_doc(U) = pretty_printer.uint64_to_doc(U). %---------------------------------------------------------------------------% :- end_module uint64. %---------------------------------------------------------------------------%