blob: 9509f7f040e8abe8e6016bbe467054849234ff7a [file] [log] [blame]
 -- \$Id: testes/bitwise.lua \$ -- See Copyright Notice in file all.lua print("testing bitwise operations") require "bwcoercion" local numbits = string.packsize('j') * 8 assert(~0 == -1) assert((1 << (numbits - 1)) == math.mininteger) -- basic tests for bitwise operators; -- use variables to avoid constant folding local a, b, c, d a = 0xFFFFFFFFFFFFFFFF assert(a == -1 and a & -1 == a and a & 35 == 35) a = 0xF0F0F0F0F0F0F0F0 assert(a | -1 == -1) assert(a ~ a == 0 and a ~ 0 == a and a ~ ~a == -1) assert(a >> 4 == ~a) a = 0xF0; b = 0xCC; c = 0xAA; d = 0xFD assert(a | b ~ c & d == 0xF4) a = 0xF0.0; b = 0xCC.0; c = "0xAA.0"; d = "0xFD.0" assert(a | b ~ c & d == 0xF4) a = 0xF0000000; b = 0xCC000000; c = 0xAA000000; d = 0xFD000000 assert(a | b ~ c & d == 0xF4000000) assert(~~a == a and ~a == -1 ~ a and -d == ~d + 1) a = a << 32 b = b << 32 c = c << 32 d = d << 32 assert(a | b ~ c & d == 0xF4000000 << 32) assert(~~a == a and ~a == -1 ~ a and -d == ~d + 1) assert(-1 >> 1 == (1 << (numbits - 1)) - 1 and 1 << 31 == 0x80000000) assert(-1 >> (numbits - 1) == 1) assert(-1 >> numbits == 0 and -1 >> -numbits == 0 and -1 << numbits == 0 and -1 << -numbits == 0) assert(1 >> math.mininteger == 0) assert(1 >> math.maxinteger == 0) assert(1 << math.mininteger == 0) assert(1 << math.maxinteger == 0) assert((2^30 - 1) << 2^30 == 0) assert((2^30 - 1) >> 2^30 == 0) assert(1 >> -3 == 1 << 3 and 1000 >> 5 == 1000 << -5) -- coercion from strings to integers assert("0xffffffffffffffff" | 0 == -1) assert("0xfffffffffffffffe" & "-1" == -2) assert(" \t-0xfffffffffffffffe\n\t" & "-1" == 2) assert(" \n -45 \t " >> " -2 " == -45 * 4) assert("1234.0" << "5.0" == 1234 * 32) assert("0xffff.0" ~ "0xAAAA" == 0x5555) assert(~"0x0.000p4" == -1) assert(("7" .. 3) << 1 == 146) assert(0xffffffff >> (1 .. "9") == 0x1fff) assert(10 | (1 .. "9") == 27) do local st, msg = pcall(function () return 4 & "a" end) assert(string.find(msg, "'band'")) local st, msg = pcall(function () return ~"a" end) assert(string.find(msg, "'bnot'")) end -- out of range number assert(not pcall(function () return "0xffffffffffffffff.0" | 0 end)) -- embedded zeros assert(not pcall(function () return "0xffffffffffffffff\0" | 0 end)) print'+' package.preload.bit32 = function () --{ -- no built-in 'bit32' library: implement it using bitwise operators local bit = {} function bit.bnot (a) return ~a & 0xFFFFFFFF end -- -- in all vararg functions, avoid creating 'arg' table when there are -- only 2 (or less) parameters, as 2 parameters is the common case -- function bit.band (x, y, z, ...) if not z then return ((x or -1) & (y or -1)) & 0xFFFFFFFF else local arg = {...} local res = x & y & z for i = 1, #arg do res = res & arg[i] end return res & 0xFFFFFFFF end end function bit.bor (x, y, z, ...) if not z then return ((x or 0) | (y or 0)) & 0xFFFFFFFF else local arg = {...} local res = x | y | z for i = 1, #arg do res = res | arg[i] end return res & 0xFFFFFFFF end end function bit.bxor (x, y, z, ...) if not z then return ((x or 0) ~ (y or 0)) & 0xFFFFFFFF else local arg = {...} local res = x ~ y ~ z for i = 1, #arg do res = res ~ arg[i] end return res & 0xFFFFFFFF end end function bit.btest (...) return bit.band(...) ~= 0 end function bit.lshift (a, b) return ((a & 0xFFFFFFFF) << b) & 0xFFFFFFFF end function bit.rshift (a, b) return ((a & 0xFFFFFFFF) >> b) & 0xFFFFFFFF end function bit.arshift (a, b) a = a & 0xFFFFFFFF if b <= 0 or (a & 0x80000000) == 0 then return (a >> b) & 0xFFFFFFFF else return ((a >> b) | ~(0xFFFFFFFF >> b)) & 0xFFFFFFFF end end function bit.lrotate (a ,b) b = b & 31 a = a & 0xFFFFFFFF a = (a << b) | (a >> (32 - b)) return a & 0xFFFFFFFF end function bit.rrotate (a, b) return bit.lrotate(a, -b) end local function checkfield (f, w) w = w or 1 assert(f >= 0, "field cannot be negative") assert(w > 0, "width must be positive") assert(f + w <= 32, "trying to access non-existent bits") return f, ~(-1 << w) end function bit.extract (a, f, w) local f, mask = checkfield(f, w) return (a >> f) & mask end function bit.replace (a, v, f, w) local f, mask = checkfield(f, w) v = v & mask a = (a & ~(mask << f)) | (v << f) return a & 0xFFFFFFFF end return bit end --} print("testing bitwise library") local bit32 = require'bit32' assert(bit32.band() == bit32.bnot(0)) assert(bit32.btest() == true) assert(bit32.bor() == 0) assert(bit32.bxor() == 0) assert(bit32.band() == bit32.band(0xffffffff)) assert(bit32.band(1,2) == 0) -- out-of-range numbers assert(bit32.band(-1) == 0xffffffff) assert(bit32.band((1 << 33) - 1) == 0xffffffff) assert(bit32.band(-(1 << 33) - 1) == 0xffffffff) assert(bit32.band((1 << 33) + 1) == 1) assert(bit32.band(-(1 << 33) + 1) == 1) assert(bit32.band(-(1 << 40)) == 0) assert(bit32.band(1 << 40) == 0) assert(bit32.band(-(1 << 40) - 2) == 0xfffffffe) assert(bit32.band((1 << 40) - 4) == 0xfffffffc) assert(bit32.lrotate(0, -1) == 0) assert(bit32.lrotate(0, 7) == 0) assert(bit32.lrotate(0x12345678, 0) == 0x12345678) assert(bit32.lrotate(0x12345678, 32) == 0x12345678) assert(bit32.lrotate(0x12345678, 4) == 0x23456781) assert(bit32.rrotate(0x12345678, -4) == 0x23456781) assert(bit32.lrotate(0x12345678, -8) == 0x78123456) assert(bit32.rrotate(0x12345678, 8) == 0x78123456) assert(bit32.lrotate(0xaaaaaaaa, 2) == 0xaaaaaaaa) assert(bit32.lrotate(0xaaaaaaaa, -2) == 0xaaaaaaaa) for i = -50, 50 do assert(bit32.lrotate(0x89abcdef, i) == bit32.lrotate(0x89abcdef, i%32)) end assert(bit32.lshift(0x12345678, 4) == 0x23456780) assert(bit32.lshift(0x12345678, 8) == 0x34567800) assert(bit32.lshift(0x12345678, -4) == 0x01234567) assert(bit32.lshift(0x12345678, -8) == 0x00123456) assert(bit32.lshift(0x12345678, 32) == 0) assert(bit32.lshift(0x12345678, -32) == 0) assert(bit32.rshift(0x12345678, 4) == 0x01234567) assert(bit32.rshift(0x12345678, 8) == 0x00123456) assert(bit32.rshift(0x12345678, 32) == 0) assert(bit32.rshift(0x12345678, -32) == 0) assert(bit32.arshift(0x12345678, 0) == 0x12345678) assert(bit32.arshift(0x12345678, 1) == 0x12345678 // 2) assert(bit32.arshift(0x12345678, -1) == 0x12345678 * 2) assert(bit32.arshift(-1, 1) == 0xffffffff) assert(bit32.arshift(-1, 24) == 0xffffffff) assert(bit32.arshift(-1, 32) == 0xffffffff) assert(bit32.arshift(-1, -1) == bit32.band(-1 * 2, 0xffffffff)) assert(0x12345678 << 4 == 0x123456780) assert(0x12345678 << 8 == 0x1234567800) assert(0x12345678 << -4 == 0x01234567) assert(0x12345678 << -8 == 0x00123456) assert(0x12345678 << 32 == 0x1234567800000000) assert(0x12345678 << -32 == 0) assert(0x12345678 >> 4 == 0x01234567) assert(0x12345678 >> 8 == 0x00123456) assert(0x12345678 >> 32 == 0) assert(0x12345678 >> -32 == 0x1234567800000000) print("+") -- some special cases local c = {0, 1, 2, 3, 10, 0x80000000, 0xaaaaaaaa, 0x55555555, 0xffffffff, 0x7fffffff} for _, b in pairs(c) do assert(bit32.band(b) == b) assert(bit32.band(b, b) == b) assert(bit32.band(b, b, b, b) == b) assert(bit32.btest(b, b) == (b ~= 0)) assert(bit32.band(b, b, b) == b) assert(bit32.band(b, b, b, ~b) == 0) assert(bit32.btest(b, b, b) == (b ~= 0)) assert(bit32.band(b, bit32.bnot(b)) == 0) assert(bit32.bor(b, bit32.bnot(b)) == bit32.bnot(0)) assert(bit32.bor(b) == b) assert(bit32.bor(b, b) == b) assert(bit32.bor(b, b, b) == b) assert(bit32.bor(b, b, 0, ~b) == 0xffffffff) assert(bit32.bxor(b) == b) assert(bit32.bxor(b, b) == 0) assert(bit32.bxor(b, b, b) == b) assert(bit32.bxor(b, b, b, b) == 0) assert(bit32.bxor(b, 0) == b) assert(bit32.bnot(b) ~= b) assert(bit32.bnot(bit32.bnot(b)) == b) assert(bit32.bnot(b) == (1 << 32) - 1 - b) assert(bit32.lrotate(b, 32) == b) assert(bit32.rrotate(b, 32) == b) assert(bit32.lshift(bit32.lshift(b, -4), 4) == bit32.band(b, bit32.bnot(0xf))) assert(bit32.rshift(bit32.rshift(b, 4), -4) == bit32.band(b, bit32.bnot(0xf))) end -- for this test, use at most 24 bits (mantissa of a single float) c = {0, 1, 2, 3, 10, 0x800000, 0xaaaaaa, 0x555555, 0xffffff, 0x7fffff} for _, b in pairs(c) do for i = -40, 40 do local x = bit32.lshift(b, i) local y = math.floor(math.fmod(b * 2.0^i, 2.0^32)) assert(math.fmod(x - y, 2.0^32) == 0) end end assert(not pcall(bit32.band, {})) assert(not pcall(bit32.bnot, "a")) assert(not pcall(bit32.lshift, 45)) assert(not pcall(bit32.lshift, 45, print)) assert(not pcall(bit32.rshift, 45, print)) print("+") -- testing extract/replace assert(bit32.extract(0x12345678, 0, 4) == 8) assert(bit32.extract(0x12345678, 4, 4) == 7) assert(bit32.extract(0xa0001111, 28, 4) == 0xa) assert(bit32.extract(0xa0001111, 31, 1) == 1) assert(bit32.extract(0x50000111, 31, 1) == 0) assert(bit32.extract(0xf2345679, 0, 32) == 0xf2345679) assert(not pcall(bit32.extract, 0, -1)) assert(not pcall(bit32.extract, 0, 32)) assert(not pcall(bit32.extract, 0, 0, 33)) assert(not pcall(bit32.extract, 0, 31, 2)) assert(bit32.replace(0x12345678, 5, 28, 4) == 0x52345678) assert(bit32.replace(0x12345678, 0x87654321, 0, 32) == 0x87654321) assert(bit32.replace(0, 1, 2) == 2^2) assert(bit32.replace(0, -1, 4) == 2^4) assert(bit32.replace(-1, 0, 31) == (1 << 31) - 1) assert(bit32.replace(-1, 0, 1, 2) == (1 << 32) - 7) -- testing conversion of floats assert(bit32.bor(3.0) == 3) assert(bit32.bor(-4.0) == 0xfffffffc) -- large floats and large-enough integers? if 2.0^50 < 2.0^50 + 1.0 and 2.0^50 < (-1 >> 1) then assert(bit32.bor(2.0^32 - 5.0) == 0xfffffffb) assert(bit32.bor(-2.0^32 - 6.0) == 0xfffffffa) assert(bit32.bor(2.0^48 - 5.0) == 0xfffffffb) assert(bit32.bor(-2.0^48 - 6.0) == 0xfffffffa) end print'OK'