1. A method for locating, preserving, and receiving registers, the method comprising: modifying a register located within a central processing unit with a preservation bit, wherein the preservation bit designates when the register is to be preserved; activating the preservation bit of the register; requesting a subroutine to access content held in the register; pushing the content to a memory source; pushing a bitmask to the memory source, wherein the bitmask contains information regarding the content pushed to the memory source; popping the bitmask, at the request of the subroutine, to determine that that content is to be popped; popping the content from the memory source to the register; and returning from the subroutine.