compile identity macro for direct usage and fixes to build_function

Author: ChrisRackauckas

src/ModelingToolkit.jl

@@ -4,7 +4,7 @@ export Operation, Expression
 export calculate_jacobian, generate_jacobian, generate_function
 export independent_variables, dependent_variables, parameters
 export simplified_expr
-export @register
+export @register, @I
 export modelingtoolkitize
 
 

src/direct.jl

@@ -25,6 +25,19 @@ function simplified_expr(O::Operation)
   return Expr(:call, Symbol(O.op), simplified_expr.(O.args)...)
 end
 
+function simplified_expr(c::Constant)
+    c.value
+end
+
 function simplified_expr(eq::Equation)
     Expr(:(=), simplified_expr(eq.lhs), simplified_expr(eq.rhs))
 end
+
+macro I(ex)
+    name = :ICompile
+    ret = return quote
+        macro $(esc(name))()
+            esc($ex)
+        end
+    end
+end

src/utils.jl

@@ -31,7 +31,7 @@ function flatten_expr!(x)
     x
 end
 
-function build_function(rhss, vs, ps, args = (), conv = rhs -> convert(Expr, rhs); constructor=nothing)
+function build_function(rhss, vs, ps, args = (), conv = simplified_expr; constructor=nothing)
     _vs = map(x-> x isa Operation ? x.op : x, vs)
     _ps = map(x-> x isa Operation ? x.op : x, ps)
     var_pairs   = [(u.name, :(u[$i])) for (i, u) ∈ enumerate(_vs)]

test/direct.jl

@@ -28,3 +28,43 @@ for i in 1:3
 end
 @test all(isequal.(ModelingToolkit.gradient(eqs[1],[x,y,z]),[σ * -1,σ,0]))
 @test all(isequal.(ModelingToolkit.hessian(eqs[1],[x,y,z]),0))
+
+@parameters σ() ρ() β()
+@variables x y z
+
+eqs = [σ*(y-x),
+       x*(ρ-z)-y,
+       x*y - β*z]
+
+ModelingToolkit.build_function(eqs,[x,y,z],[σ,ρ,β])
+
+mac = @I begin
+   @parameters σ() ρ() β()
+   @variables x() y() z()
+
+   eqs = [σ*(y-x),
+          x*(ρ-z)-y,
+          x*y - β*z]
+
+   ModelingToolkit.build_function(eqs,[x,y,z],[σ,ρ,β])
+end
+f = @ICompile
+out = [1.0,2,3]
+f([1.0,2,3],[1.0,2,3])
+f(out,[1.0,2,3],[1.0,2,3])
+
+mac = @I begin
+   @parameters σ() ρ() β()
+   @variables x() y() z()
+
+   eqs = [σ*(y-x),
+          x*(ρ-z)-y,
+          x*y - β*z]
+   ∂ = ModelingToolkit.jacobian(eqs,[x,y,z])
+   ModelingToolkit.build_function(∂,[x,y,z],[σ,ρ,β])
+end
+f = @ICompile
+out = zeros(3,3)
+f([1.0,2,3],[1.0,2,3])
+f(out,[1.0,2,3],[1.0,2,3])
+out