Generate prefetch code in execution order and then inject backwards
Generate prefetch code in execution order and then inject backwards


Former-commit-id: 65454f8ae7ef892d2476f194ea4a3424a3df0a40
Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,darkbuck/Halide