1. At least one non-transitory computer-readable medium having computer-readable code embodied therein, the computer-readable code configured to enable a computing device, in response to execution of the code, to: identify and encrypt a first subset of a first plurality of instructions, wherein the first subset comprises a basic block including a second plurality of instructions of the first plurality of instructions, wherein the basic block includes only a single entry point and only a single exit point, to enable one or more instructions of the first plurality of instructions that precede or follow the first subset to be executed in a first execution environment with a first security level, and to enable the first subset to be executed in a second execution environment with a second security level that is more secure than the first security level; identify and encrypt a second subset; and concatenate the first and second subsets, the first and second subsets to be executed in the second execution environment; and generate an index of the concatenated first and second subsets, the index to include a relative virtual address associated with at least one of the first and second subsets.