raze-gles/polymer/eduke32/source/lunatic/test/test_bitar.lua
2013-04-09 17:35:03 +00:00

147 lines
3.6 KiB
Lua
Executable file

#!/usr/bin/env luajit
-- Usage: luajit bittest.lua <number or "x"> [-ffi] [-bchk]
local string = require "string"
local math = require "math"
local bitar = require "bitar"
local print = print
local tonumber = tonumber
local getticks
if (string.dump) then
-- stand-alone
local os = require "os"
function getticks()
return os.clock()*1000
end
else
-- embedded
getticks = gv.gethitickms
module(...)
end
-- based on example from http://bitop.luajit.org/api.html
local m = string.dump and tonumber(arg[1]) or 1e7
local maxidx = math.floor(m/32)
local ffiar_p, boundchk_p = false, false
if (string.dump) then
if (arg[2]=="-ffi" or arg[3]=="-ffi") then
ffiar_p = true
end
if (arg[2]=="-bchk" or arg[3]=="-bchk") then
boundchk_p = true
end
end
function sieve()
local count = 0
local p = {}
if (ffiar_p) then
-- stand-alone using unchecked int32_t array: on x86_64 approx. 80 ms
-- for m = 1e7 (enabling bound checking makes it be around 100 ms)
local ffi = require "ffi"
local pp = ffi.new("int32_t [?]", maxidx + 1)
p = pp
if (boundchk_p) then
local mt = {
__index = function(tab,idx)
if (idx >= 0 and idx <= maxidx) then
return pp[idx]
end
end,
__newindex = function(tab,idx,val)
if (idx >= 0 and idx <= maxidx) then
pp[idx] = val
end
end,
}
p = setmetatable({}, mt)
end
for i=0,maxidx do p[i] = -1; end
else
p = bitar.new(m, 1)
end
local t = getticks()
if (ffiar_p) then
local bit = require "bit"
for i=2,m do
if (bit.band(p[bit.rshift(i, 5)], bit.lshift(1, i)) ~= 0) then
count = count + 1
for j=i+i,m,i do
local jx = bit.rshift(j, 5)
p[jx] = bit.band(p[jx], bit.rol(0xfffffffe, j));
end
end
end
else
for i=2,m do
if (p:isset(i)) then
count = count + 1
for j=i+i,m,i do p:set0(j); end
end
end
end
-- When using bitar module: x86_64: approx. 110 ms
print(string.format("[%s] Found %d primes up to %d (%.02f ms)",
ffiar_p and "ffi-ar"..(boundchk_p and ", bchk" or "") or "tab-ar",
count, m, getticks()-t))
return p, count
end
if (string.dump) then
local function printf(fmt, ...) print(string.format(fmt, ...)) end
local p, count = sieve()
local t = getticks()
if (ffiar_p) then
return
end
-- test serialization
local ser = tostring(p)
local maxbidx_str = string.match(ser, '%(([0-9]+),')
local p2 = bitar.new(tonumber(maxbidx_str), string.match(ser, "'(.*)'"))
printf("serialization + new: %.02f ms", tostring(getticks()-t))
assert(p==p2)
if (m >= 2) then
assert(#p == count+2) -- +2 is because 0 and 1 are set even though they're not primes
end
if (not ffiar_p) then
math.randomseed(os.time())
local maxbidx = math.random(0, 65536)
local p3 = bitar.new(maxbidx, 1)
assert(#p3 == maxbidx+1) -- bits 0 to maxbidx inclusive are set
end
--[[
print(p)
print(p-p) -- test set difference
print(-p)
--]]
-- Set difference of self with self is the same as set intersection of self
-- with complement of self:
assert(p-p == p*(-p))
end