Better local_laplacian schedule
Better local_laplacian schedule

The parallelism was too fine-grained


Former-commit-id: 64586768ce3aa3aa45ba2d910d4e6da6457e74b4
Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,Trass3r/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide