Split simplify_test into several functions to avoid -fvar-tracking-assignments warning.
Split simplify_test into several functions to avoid -fvar-tracking-assignments warning.


Former-commit-id: 1b4ef98f6ec1e58af67808a03300ec76b774d27e
Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,darkbuck/Halide