samples: add Terra samples

source: https://github.com/zdevito/terra/tree/master/tests

samples/Terra/blocking2-fixed.t

@@ -0,0 +1,68 @@
+C = terralib.includec("stdio.h")
+
+terra min(a: int, b: int) : int
+  if a < b then return a
+  else return b end
+end
+std = terralib.includec("stdlib.h")
+function Image(PixelType)
+  local struct ImageImpl {
+    data : &PixelType,
+    N : int
+  }
+  terra ImageImpl:init(N: int): {} --returns nothing
+    self.data = [&PixelType](
+      std.malloc(N*N*sizeof(PixelType)))
+    self.N = N
+  end
+  terra ImageImpl:get(x: int, y: int) : PixelType
+    return self.data[x*self.N + y]
+  end
+  
+
+  terra ImageImpl:set(x: int, y: int, v : PixelType)
+    self.data[x*self.N + y] = v
+  end
+  terra ImageImpl:save(i : rawstring) 
+    for i = 0, 2 do for j = 0, 2 do
+      C.printf("%d %d %f\n", i,j,self:get(i,j))
+    end end
+  end
+  terra ImageImpl:load(i : rawstring) self:init(16)
+    for i = 0, 4 do for j = 0, 4 do
+    	self:set(i,j,(i*4+j)%3)
+    	--C.printf("%f\n",self:get(i,j))
+    end end
+  end
+  terra ImageImpl:free() end
+
+  --omitted methods for: set, save, load, free
+  return ImageImpl
+end
+GreyscaleImage = Image(float)
+terra laplace(img: &GreyscaleImage, 
+              out: &GreyscaleImage) : {}
+  --shrink result, do not calculate boundaries
+  var newN = img.N - 2 
+  out:init(newN)
+  for i = 0,newN do
+    for j = 0,newN do
+      var v = img:get(i+0,j+1) + img:get(i+2,j+1)
+            + img:get(i+1,j+2) + img:get(i+1,j+0)
+            - 4 * img:get(i+1,j+1)
+      out:set(i,j,v)
+    end
+  end
+end
+terra runlaplace(input: rawstring, 
+                 output: rawstring) : {}
+    var i: GreyscaleImage, o : GreyscaleImage
+    i:load(input)
+    laplace(&i,&o)
+    o:save(output)
+    i:free(); o:free()
+end
+
+runlaplace("myinput","myoutput")
+ terralib.saveobj("runlaplace.o", 
+                 {runlaplace = runlaplace})