মডিউল:bit32
এই মডিউলের জন্য মডিউল:bit32/নথি-এ নথিপত্র তৈরি করা হয়ে থাকতে পারে
-- Convert number to int
local to_int = math.floor
local abs = math.abs
-- Convert number to 32-bit unsigned int
local function to_int32(x)
-- x % y >= 0 if y >= 0
return to_int(x) % 0x100000000
end
-- 4x4 bit OR table, e.g. or_44[0x4E] = 0x4 | 0xE
local or_44 = {
[0] = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
1, 1, 3, 3, 5, 5, 7, 7, 9, 9, 11, 11, 13, 13, 15, 15,
2, 3, 2, 3, 6, 7, 6, 7, 10, 11, 10, 11, 14, 15, 14, 15,
3, 3, 3, 3, 7, 7, 7, 7, 11, 11, 11, 11, 15, 15, 15, 15,
4, 5, 6, 7, 4, 5, 6, 7, 12, 13, 14, 15, 12, 13, 14, 15,
5, 5, 7, 7, 5, 5, 7, 7, 13, 13, 15, 15, 13, 13, 15, 15,
6, 7, 6, 7, 6, 7, 6, 7, 14, 15, 14, 15, 14, 15, 14, 15,
7, 7, 7, 7, 7, 7, 7, 7, 15, 15, 15, 15, 15, 15, 15, 15,
8, 9, 10, 11, 12, 13, 14, 15, 8, 9, 10, 11, 12, 13, 14, 15,
9, 9, 11, 11, 13, 13, 15, 15, 9, 9, 11, 11, 13, 13, 15, 15,
10, 11, 10, 11, 14, 15, 14, 15, 10, 11, 10, 11, 14, 15, 14, 15,
11, 11, 11, 11, 15, 15, 15, 15, 11, 11, 11, 11, 15, 15, 15, 15,
12, 13, 14, 15, 12, 13, 14, 15, 12, 13, 14, 15, 12, 13, 14, 15,
13, 13, 15, 15, 13, 13, 15, 15, 13, 13, 15, 15, 13, 13, 15, 15,
14, 15, 14, 15, 14, 15, 14, 15, 14, 15, 14, 15, 14, 15, 14, 15,
15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
}
-- 4x4 bit AND table, e.g. and_44[0x4E] = 0x4 & 0xE
local and_44 = {
[0] = 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
0, 0, 2, 2, 0, 0, 2, 2, 0, 0, 2, 2, 0, 0, 2, 2,
0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3,
0, 0, 0, 0, 4, 4, 4, 4, 0, 0, 0, 0, 4, 4, 4, 4,
0, 1, 0, 1, 4, 5, 4, 5, 0, 1, 0, 1, 4, 5, 4, 5,
0, 0, 2, 2, 4, 4, 6, 6, 0, 0, 2, 2, 4, 4, 6, 6,
0, 1, 2, 3, 4, 5, 6, 7, 0, 1, 2, 3, 4, 5, 6, 7,
0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8,
0, 1, 0, 1, 0, 1, 0, 1, 8, 9, 8, 9, 8, 9, 8, 9,
0, 0, 2, 2, 0, 0, 2, 2, 8, 8, 10, 10, 8, 8, 10, 10,
0, 1, 2, 3, 0, 1, 2, 3, 8, 9, 10, 11, 8, 9, 10, 11,
0, 0, 0, 0, 4, 4, 4, 4, 8, 8, 8, 8, 12, 12, 12, 12,
0, 1, 0, 1, 4, 5, 4, 5, 8, 9, 8, 9, 12, 13, 12, 13,
0, 0, 2, 2, 4, 4, 6, 6, 8, 8, 10, 10, 12, 12, 14, 14,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
}
-- 4x4 bit XOR table, e.g. xor_44[0x4E] = 0x4 ^ 0xE
local xor_44 = {
[0] = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
1, 0, 3, 2, 5, 4, 7, 6, 9, 8, 11, 10, 13, 12, 15, 14,
2, 3, 0, 1, 6, 7, 4, 5, 10, 11, 8, 9, 14, 15, 12, 13,
3, 2, 1, 0, 7, 6, 5, 4, 11, 10, 9, 8, 15, 14, 13, 12,
4, 5, 6, 7, 0, 1, 2, 3, 12, 13, 14, 15, 8, 9, 10, 11,
5, 4, 7, 6, 1, 0, 3, 2, 13, 12, 15, 14, 9, 8, 11, 10,
6, 7, 4, 5, 2, 3, 0, 1, 14, 15, 12, 13, 10, 11, 8, 9,
7, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8,
8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7,
9, 8, 11, 10, 13, 12, 15, 14, 1, 0, 3, 2, 5, 4, 7, 6,
10, 11, 8, 9, 14, 15, 12, 13, 2, 3, 0, 1, 6, 7, 4, 5,
11, 10, 9, 8, 15, 14, 13, 12, 3, 2, 1, 0, 7, 6, 5, 4,
12, 13, 14, 15, 8, 9, 10, 11, 4, 5, 6, 7, 0, 1, 2, 3,
13, 12, 15, 14, 9, 8, 11, 10, 5, 4, 7, 6, 1, 0, 3, 2,
14, 15, 12, 13, 10, 11, 8, 9, 6, 7, 4, 5, 2, 3, 0, 1,
15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0,
}
local function b44(tbl, dflt, ...)
-- apply bitwise operation in 4-bit chunks.
-- tbl is the table of 16x16 values used to perform bitop on 4-bit blocks
-- dflt is a default value if no args given
local arg = { ... }
local to_int = to_int
local x = to_int32(arg[1] or dflt)
local y, r
for i = 2, # arg do
y = to_int32(arg[i])
-- for i = 1, 8 do
-- r, q = r + q * tbl[(to_int(x / q) % 16) * 16 + (to_int(y / q) % 16)], q * 16
-- end
-- x = r
-- inlined, with optimizations and precomputation:
x = ( tbl[( x % 16) * 16 + ( y % 16)] +
0x00000010 * tbl[(to_int(x / 0x00000010) % 16) * 16 + (to_int(y / 0x00000010) % 16)] +
0x00000100 * tbl[(to_int(x / 0x00000100) % 16) * 16 + (to_int(y / 0x00000100) % 16)] +
0x00001000 * tbl[(to_int(x / 0x00001000) % 16) * 16 + (to_int(y / 0x00001000) % 16)] +
0x00010000 * tbl[(to_int(x / 0x00010000) % 16) * 16 + (to_int(y / 0x00010000) % 16)] +
0x00100000 * tbl[(to_int(x / 0x00100000) % 16) * 16 + (to_int(y / 0x00100000) % 16)] +
0x01000000 * tbl[(to_int(x / 0x01000000) % 16) * 16 + (to_int(y / 0x01000000) % 16)] +
0x10000000 * tbl[(to_int(x / 0x10000000) ) * 16 + (to_int(y / 0x10000000) )])
end
return x
end
local function band(...)
return b44(and_44, -1, ...)
end
local function bor(...)
return b44(or_44, 0, ...)
end
local function bxor(...)
return b44(xor_44, 0, ...)
end
local function bnot(x)
return 0xFFFFFFFF - to_int32(x)
end
local function btest(...)
return band(...) ~= 0
end
local function lshift(n, disp)
disp = to_int(disp)
return abs(disp) >= 32 and 0 or (to_int32(n) * (2 ^ disp)) % 0x100000000
end
local function rshift(n, disp)
disp = to_int(disp)
return abs(disp) >= 32 and 0 or to_int(to_int32(n) * (2 ^ -disp))
end
local function arshift(n, disp)
n = to_int32(n)
disp = to_int(disp)
local r = abs(disp) >= 32 and 0 or to_int(n * (2 ^ -disp))
if n >= 0x80000000 then
if disp >= 32 then
r = 0xFFFFFFFF
elseif disp > 0 then
r = r + to_int32(0xFFFFFFFF * 2 ^ (32 - disp))
end
end
return r
end
local function lrotate(n, disp)
n = n * 2 ^ (to_int(disp) % 32)
return to_int(n / 0x100000000) + to_int32(n)
end
local function rrotate(n, disp)
n = n * 2 ^ (32 - (to_int(disp) % 32))
return to_int(n / 0x100000000) + to_int32(n)
end
local function extract(n, field, width)
width = to_int(width or 1)
field = to_int(field)
if field < 0 or field + width > 32 or width < 0 then
error("trying to access non-existent bits")
end
return to_int(to_int32(n) * 2 ^ -field) % (2 ^ width)
end
local function replace(n, v, field, width)
width = to_int(width or 1)
field = to_int(field)
if field < 0 or field + width > 32 or width < 0 then
error("trying to access non-existent bits")
end
local field_shift = 2 ^ field
local field_width = 2 ^ width
return band(n, 0xFFFFFFFF - field_shift * (field_width - 1)) + field_shift * (v % field_width)
end
return {
band = band,
bor = bor,
bxor = bxor,
bnot = bnot,
btest = btest,
lshift = lshift,
rshift = rshift,
arshift = arshift,
lrotate = lrotate,
rrotate = rrotate,
extract = extract,
replace = replace,
}