Fix the types, add some profiling examples (#15)

Reviewed-on: Rubydragon/MetagraphOptimization.jl#15
Co-authored-by: Anton Reinhard <anton.reinhard@proton.me>
Co-committed-by: Anton Reinhard <anton.reinhard@proton.me>

src/code_gen/main.jl

@@ -79,7 +79,7 @@ function gen_input_assignment_code(
             # TODO: how to get the "default" cpu device?
             device = entry_device(machine)
             evalExpr = eval(gen_access_expr(device, symbol))
-            push!(assignInputs, Meta.parse("$(evalExpr) = ParticleValue($p, 1.0)"))
+            push!(assignInputs, Meta.parse("$(evalExpr)::ParticleValue{$type} = ParticleValue($p, 1.0)"))
         end
     end
 
@@ -102,6 +102,7 @@ function get_compute_function(graph::DAG, process::AbstractProcessDescription, m
     expr = Meta.parse(
         "function compute_$(functionId)(input::AbstractProcessInput) $initCaches; $assignInputs; $code; return $resSym; end",
     )
+
     func = eval(expr)
 
     return func