Added inferred types and missing length function.

test/codegen/inferred_types.golden

@@ -0,0 +1,24 @@
+float bar();
+float foo();
+
+float bar()
+{
+    return 5.0f;
+}
+
+float foo()
+{
+    return bar();
+}
+
+float4 vs_main(float3 pos : POSITION) : SV_POSITION
+{
+    float f = 2.0f;
+    int i = 10;
+    f = foo();
+    float2 v2 = float2(2, 2);
+    float3 v3 = float3(2, 2, 3);
+    float4 v4 = float4(4, 5, 6, 7);
+    return float4(1, 1, 1, 1);
+}
+