Add stage 06: Lua bootstrap

The goal of stage 06 is to try parse zig synax in lua. I pulled in
lpeglable 1.2.0 and parser-gen off github to get started. All of this
needs to be cleaned up rather soon.

Lua boostraps using tcc and musl from the previous stage. Since musl
0.6.0 doesn't support dynamic linking this build of lua doesn't support
shared libraries. I couldn't easily patch musl with dlopen and friends
so instead I link statically and call deps with c api.

06/parser-gen/parsers/lua-5.3.4-tests/verybig.lua

@@ -0,0 +1,152 @@
+-- $Id: verybig.lua,v 1.25 2016/11/07 13:11:28 roberto Exp $
+-- See Copyright Notice in file all.lua
+
+print "testing RK"
+
+-- testing opcodes with RK arguments larger than K limit
+local function foo ()
+  local dummy = {
+     -- fill first 256 entries in table of constants
+     1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,
+     17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,
+     33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
+     49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64,
+     65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80,
+     81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96,
+     97, 98, 99, 100, 101, 102, 103, 104,
+     105, 106, 107, 108, 109, 110, 111, 112,
+     113, 114, 115, 116, 117, 118, 119, 120,
+     121, 122, 123, 124, 125, 126, 127, 128,
+     129, 130, 131, 132, 133, 134, 135, 136,
+     137, 138, 139, 140, 141, 142, 143, 144,
+     145, 146, 147, 148, 149, 150, 151, 152,
+     153, 154, 155, 156, 157, 158, 159, 160,
+     161, 162, 163, 164, 165, 166, 167, 168,
+     169, 170, 171, 172, 173, 174, 175, 176,
+     177, 178, 179, 180, 181, 182, 183, 184,
+     185, 186, 187, 188, 189, 190, 191, 192,
+     193, 194, 195, 196, 197, 198, 199, 200,
+     201, 202, 203, 204, 205, 206, 207, 208,
+     209, 210, 211, 212, 213, 214, 215, 216,
+     217, 218, 219, 220, 221, 222, 223, 224,
+     225, 226, 227, 228, 229, 230, 231, 232,
+     233, 234, 235, 236, 237, 238, 239, 240,
+     241, 242, 243, 244, 245, 246, 247, 248,
+     249, 250, 251, 252, 253, 254, 255, 256,
+  }
+  assert(24.5 + 0.6 == 25.1)
+  local t = {foo = function (self, x) return x + self.x end, x = 10}
+  t.t = t
+  assert(t:foo(1.5) == 11.5)
+  assert(t.t:foo(0.5) == 10.5)   -- bug in 5.2 alpha
+  assert(24.3 == 24.3)
+  assert((function () return t.x end)() == 10)
+end
+
+
+foo()
+foo = nil
+
+if _soft then return 10 end
+
+print "testing large programs (>64k)"
+
+-- template to create a very big test file
+prog = [[$
+
+local a,b
+
+b = {$1$
+  b30009 = 65534,
+  b30010 = 65535,
+  b30011 = 65536,
+  b30012 = 65537,
+  b30013 = 16777214,
+  b30014 = 16777215,
+  b30015 = 16777216,
+  b30016 = 16777217,
+  b30017 = 0x7fffff,
+  b30018 = -0x7fffff,
+  b30019 = 0x1ffffff,
+  b30020 = -0x1ffffd,
+  b30021 = -65534,
+  b30022 = -65535,
+  b30023 = -65536,
+  b30024 = -0xffffff,
+  b30025 = 15012.5,
+  $2$
+};
+
+assert(b.a50008 == 25004 and b["a11"] == -5.5)
+assert(b.a33007 == -16503.5 and b.a50009 == -25004.5)
+assert(b["b"..30024] == -0xffffff)
+
+function b:xxx (a,b) return a+b end
+assert(b:xxx(10, 12) == 22)   -- pushself with non-constant index
+b.xxx = nil
+
+s = 0; n=0
+for a,b in pairs(b) do s=s+b; n=n+1 end
+-- with 32-bit floats, exact value of 's' depends on summation order
+assert(81800000.0 < s and s < 81860000 and n == 70001)
+
+a = nil; b = nil
+print'+'
+
+function f(x) b=x end
+
+a = f{$3$} or 10
+
+assert(a==10)
+assert(b[1] == "a10" and b[2] == 5 and b[#b-1] == "a50009")
+
+
+function xxxx (x) return b[x] end
+
+assert(xxxx(3) == "a11")
+
+a = nil; b=nil
+xxxx = nil
+
+return 10
+
+]]
+
+-- functions to fill in the $n$
+
+local function sig (x)
+  return (x % 2 == 0) and '' or '-'
+end
+
+F = {
+function ()   -- $1$
+  for i=10,50009 do
+    io.write('a', i, ' = ', sig(i), 5+((i-10)/2), ',\n')
+  end
+end,
+
+function ()   -- $2$
+  for i=30026,50009 do
+    io.write('b', i, ' = ', sig(i), 15013+((i-30026)/2), ',\n')
+  end
+end,
+
+function ()   -- $3$
+  for i=10,50009 do
+    io.write('"a', i, '", ', sig(i), 5+((i-10)/2), ',\n')
+  end
+end,
+}
+
+file = os.tmpname()
+io.output(file)
+for s in string.gmatch(prog, "$([^$]+)") do
+  local n = tonumber(s)
+  if not n then io.write(s) else F[n]() end
+end
+io.close()
+result = dofile(file)
+assert(os.remove(file))
+print'OK'
+return result
+