-- $Id: code.lua,v 1.42 2016/11/07 13:04:32 roberto Exp $
-- See Copyright Notice in file all.lua

if T == nil then
  (Message or print)('\n >>> testC not active: skipping opcode tests <<<\n')
  return
end
print "testing code generation and optimizations"


-- this code gave an error for the code checker
do
  local function f(a)
    for k, v, w in a do end
  end
end


-- testing reuse in constant table
local function checkKlist(func, list)
  local k = T.listk(func)
  assert(#k == #list)
  for i = 1, #k do
    assert(k[i] == list[i] and math.type(k[i]) == math.type(list[i]))
  end
end

local function foo()
  local a
  a = 3;
  a = 0; a = 0.0; a = -7 + 7
  a = 3.78 / 4; a = 3.78 / 4
  a = -3.78 / 4; a = 3.78 / 4; a = -3.78 / 4
  a = -3.79 / 4; a = 0.0; a = -0;
  a = 3; a = 3.0; a = 3; a = 3.0
end

checkKlist(foo, { 3, 0, 0.0, 3.78 / 4, -3.78 / 4, -3.79 / 4, 3.0 })


-- testing opcodes

function check(f, ...)
  local arg = { ... }
  local c = T.listcode(f)
  for i = 1, #arg do
    -- print(arg[i], c[i])
    assert(string.find(c[i], '- ' .. arg[i] .. ' *%d'))
  end
  assert(c[#arg + 2] == nil)
end

function checkequal(a, b)
  a = T.listcode(a)
  b = T.listcode(b)
  for i = 1, #a do
    a[i] = string.gsub(a[i], '%b()', '') -- remove line number
    b[i] = string.gsub(b[i], '%b()', '') -- remove line number
    assert(a[i] == b[i])
  end
end

-- some basic instructions
check(function()
  (function() end) { f() }
end, 'CLOSURE', 'NEWTABLE', 'GETTABUP', 'CALL', 'SETLIST', 'CALL', 'RETURN')


-- sequence of LOADNILs
check(function()
  local a, b, c
  local d; local e;
  local f, g, h;
  d = nil; d = nil; b = nil; a = nil; c = nil;
end, 'LOADNIL', 'RETURN')

check(function()
  local a, b, c, d = 1, 1, 1, 1
  d = nil; c = nil; b = nil; a = nil
end, 'LOADK', 'LOADK', 'LOADK', 'LOADK', 'LOADNIL', 'RETURN')

do
  local a, b, c, d = 1, 1, 1, 1
  d = nil; c = nil; b = nil; a = nil
  assert(a == nil and b == nil and c == nil and d == nil)
end


-- single return
check(function(a, b, c) return a end, 'RETURN')


-- infinite loops
check(function() while true do local a = -1 end end,
  'LOADK', 'JMP', 'RETURN')

check(function() while 1 do local a = -1 end end,
  'LOADK', 'JMP', 'RETURN')

check(function() repeat local x = 1 until true end,
  'LOADK', 'RETURN')


-- concat optimization
check(function(a, b, c, d) return a .. b .. c .. d end,
  'MOVE', 'MOVE', 'MOVE', 'MOVE', 'CONCAT', 'RETURN')

-- not
check(function() return not not nil end, 'LOADBOOL', 'RETURN')
check(function() return not not false end, 'LOADBOOL', 'RETURN')
check(function() return not not true end, 'LOADBOOL', 'RETURN')
check(function() return not not 1 end, 'LOADBOOL', 'RETURN')

-- direct access to locals
check(function()
    local a, b, c, d
    a = b * 2
    c[2], a[b] = -((a + d / 2 - a[b]) ^ a.x), b
  end,
  'LOADNIL',
  'MUL',
  'DIV', 'ADD', 'GETTABLE', 'SUB', 'GETTABLE', 'POW',
  'UNM', 'SETTABLE', 'SETTABLE', 'RETURN')


-- direct access to constants
check(function()
    local a, b
    a.x = 3.2
    a.x = b
    a[b] = 'x'
  end,
  'LOADNIL', 'SETTABLE', 'SETTABLE', 'SETTABLE', 'RETURN')

check(function()
    local a, b
    a = 1 - a
    b = 1 / a
    b = 5 - 4
  end,
  'LOADNIL', 'SUB', 'DIV', 'LOADK', 'RETURN')

check(function()
    local a, b
    a[true] = false
  end,
  'LOADNIL', 'SETTABLE', 'RETURN')


-- constant folding
local function checkK(func, val)
  check(func, 'LOADK', 'RETURN')
  local k = T.listk(func)
  assert(#k == 1 and k[1] == val and math.type(k[1]) == math.type(val))
  assert(func() == val)
end
checkK(function() return 0.0 end, 0.0)
checkK(function() return 0 end, 0)
checkK(function() return -0 // 1 end, 0)
checkK(function() return 3 ^ -1 end, 1 / 3)
checkK(function() return (1 + 1) ^ (50 + 50) end, 2 ^ 100)
checkK(function() return (-2) ^ (31 - 2) end, -0x20000000 + 0.0)
checkK(function() return (-3 ^ 0 + 5) // 3.0 end, 1.0)
checkK(function() return -3 % 5 end, 2)
checkK(function() return -((2.0 ^ 8 + -(-1)) % 8) / 2 * 4 - 3 end, -5.0)
checkK(function() return -((2 ^ 8 + -(-1)) % 8) // 2 * 4 - 3 end, -7.0)
checkK(function() return 0xF0.0 | 0xCC.0 ~ 0xAA & 0xFD end, 0xF4)
checkK(function() return ~(~0xFF0 | 0xFF0) end, 0)
checkK(function() return ~ ~ -100024.0 end, -100024)
checkK(function() return ((100 << 6) << -4) >> 2 end, 100)


-- no foldings
check(function() return -0.0 end, 'LOADK', 'UNM', 'RETURN')
check(function() return 3 / 0 end, 'DIV', 'RETURN')
check(function() return 0 % 0 end, 'MOD', 'RETURN')
check(function() return -4 // 0 end, 'IDIV', 'RETURN')

-- bug in constant folding for 5.1
check(function() return -nil end, 'LOADNIL', 'UNM', 'RETURN')


check(function()
    local a, b, c
    b[c], a = c, b
    b[a], a = c, b
    a, b = c, a
    a = a
  end,
  'LOADNIL',
  'MOVE', 'MOVE', 'SETTABLE',
  'MOVE', 'MOVE', 'MOVE', 'SETTABLE',
  'MOVE', 'MOVE', 'MOVE',
  -- no code for a = a
  'RETURN')


-- x == nil , x ~= nil
checkequal(function()
    if (a == nil) then a = 1 end
    ; if a ~= nil then a = 1 end
  end,
  function()
    if (a == 9) then a = 1 end
    ; if a ~= 9 then a = 1 end
  end)

check(function() if a == nil then a = 'a' end end,
  'GETTABUP', 'EQ', 'JMP', 'SETTABUP', 'RETURN')

-- de morgan
checkequal(function()
    local a; if not (a or b) then b = a end
  end,
  function()
    local a; if (not a and not b) then b = a end
  end)

checkequal(function(l)
    local a; return 0 <= a and a <= l
  end,
  function(l)
    local a; return not (not (a >= 0) or not (a <= l))
  end)


-- if-goto optimizations
check(function(a, b, c, d, e)
  if a == b then
  elseif a == c then
  elseif a == d then
  else
    if a == e then
    else
    end
  end
end, 'EQ', 'JMP', 'EQ', 'JMP', 'EQ', 'JMP', 'EQ', 'JMP', 'JMP', 'RETURN')

checkequal(
  function(a) while a < 10 do a = a + 1 end end,
  function(a)
    if not (a < 10) then end
    ; a = a + 1;
  end
)

checkequal(
  function(a) while a < 10 do a = a + 1 end end,
  function(a)
    while true do
      if not (a < 10) then break end
      ; a = a + 1;
    end
  end
)

print 'OK'