'CONFIGURATION
'=============

% max     8192  'Maximum amount of Prime Numbers (must be 2^n) (excluding 1 and 2)
% cores   4     'CPU cores available (limited to 4 here)
% share   2048  'Amount of numbers allocated to each core

'SETUP
'=====

'SOURCE DATA BUFFERS

sys primes[max]
sys numbers[max]

'RESULT BUFFER

double pp[max] 'main thread


'MULTITHREADING AND TIMING API
'=============================

extern lib "kernel32.dll"
'
void   QueryPerformanceCounter(quad*c)
void   QueryPerformanceFrequency(quad*freq)
sys    CreateThread (sys lpThreadAttributes, dwStackSize, lpStartAddress, lpParameter, dwCreationFlags, *lpThreadId)
dword  WaitForMultipleObjects(sys nCount,*lpHandles, bWaitAll, dwMilliseconds)
bool   CloseHandle(sys hObject)
void   Sleep(sys dwMilliSeconds)
'
quad freq,t1,t2
QueryPerformanceFrequency freq


'MACROS AND FUNCTIONS
'====================


macro FindPrimes(p)
'==================
finit
sys n=1
sys c,k
do
  n+=2
  if c>=max then exit do
  '
  'IS IT DIVISIBLE BE ANY PREVIOUS PRIME
  '
  for k=1 to c
     if frac(n/p[k])=0 then exit for
  next
  '
  if k>c then
    c++
    p[c]=n 'STORE PRIME
  end if
end do
end macro


macro ProcessNumbers(p,bb)
'=========================
finit
sys i,b,e
b=bb*share
e=b+share
sys v,w
for i=b+1 to e
  v=numbers(i)
  for j=max to 1 step -1
    w=primes(j)
    if w<v then
      if frac(v/w)=0 then
        p(i)=primes(j)    'store highest factor
        exit for          'process next number
      end if
    end if
  next
next
end macro

'THREAD FUNCTIONS

function threadA(sys v) as sys
ProcessNumbers(pp,v)
end function


function threadB(sys v) as sys
ProcessNumbers(pp,v)
end function


function threadC(sys v) as sys
ProcessNumbers(pp,v)
end function


end extern

function mainThread(sys b)
'===========================
ProcessNumbers(pp,b)
end function


'SOURCE DATA GENERATION

sys seed = 0x12345678

function Rnd() as sys
'====================
'
mov eax,seed
rol eax,7
imul eax,eax,13
mov seed,eax
return eax
end function


function GenerateNumbers()
'=========================
sys i,v,mask
mask=max * 8 -1 'as bit mask
for i=1 to max
  v=rnd()
  v and=mask
  numbers(i)=v
next
end function



FindPrimes(primes)

GenerateNumbers()



% threads Cores-1

% INFINITE 0xFFFFFFFF  'Infinite timeout

sys Funs[threads]={@threadA,@threadB,@threadC} '3 additional threads
sys  hThread[threads], id[threads], i
'
'START TIMER
'
QueryPerformanceCounter   t1
'
for i=1 to threads
  hThread(i) =  CreateThread 0,0,funs(i),i,0,id(i)
next


MainThread(0) 'process numbers in main thread (bottom share)

if threads>0 then
  WaitForMultipleObjects Threads, hThread, 1, INFINITE
end if

for i=1 to Threads
  CloseHandle hThread(i)
next

'CAPTURE NUMBER WITH HIGHEST PRIME FACTOR

sys n,f
for i=1 to max
  if pp(i)>f then f=pp(i) : n=i
next

'STOP TIMER

QueryPerformanceCounter t2

print str((t2-t1)/freq,3) " secs    " numbers(n) "    " f 'number with highest prime factor