The various embodiments of the invention relate generally to computer software, computer program architecture, software development, and computer programming languages, and more specifically, to techniques for analyzing control flow in COBOL-sourced programs to facilitate optimized conversions to object-oriented program structures. For example, a compiler can include a global optimizer configured to analyze execution flow for a range of blocks of source code in the memory to determine flow-affected code. Also, the compiler can include a native code generator configured to generate native code based on representations of the native code as functions of the source code. The native code is configured to execute on a virtual machine.