6. The computer-implemented method of claim 1 , wherein said prior to compilation of a program into machine code, generating directives about the program, the directives for directing compilation of the program into machine code by a just-in-time compiler, comprises: generating the directives about the program for compilation of the program into machine code for a specific type of processing unit.
6. The computer-implemented method of claim 1 , wherein said prior to compilation of a program into machine code, generating directives about the program, the directives for directing compilation of the program into machine code by a just-in-time compiler, comprises: generating the directives about the program for compilation of the program into machine code for a specific type of processing unit. 7. The computer-implemented method of claim 6 , further comprising: compiling the at least a portion of the bytecode representation into machine code for a second type of processing unit in one-pass with the just-in-time compiler utilizing the embedded directives.