Synthesis of machine code from semantics

In this paper, we present a technique to synthesize machine-code instructions from a semantic specification, given as a Quantifier-Free Bit-Vector (QFBV) logic formula. Our technique uses an instantiation of the Counter-Example Guided Inductive Synthesis (CEGIS) framework, in combination with search-space pruning heuristics to synthesize instruction-sequences. To counter the exponential cost inherent in enumerative synthesis, our technique uses a divideand-conquer strategy to break the input QFBV formula into independent sub-formulas, and synthesize instructions for the subformulas. Synthesizers created by our technique could be used to create semantics-based binary rewriting tools such as optimizers, partial evaluators, program obfuscators/de-obfuscators, etc. Our experiments for Intel’s IA-32 instruction set show that, in comparison to our baseline algorithm, our search-space pruning heuristics reduce the synthesis time by a factor of 473, and our divide-andconquer strategy redu...

• Type: Journal
• Year: 2015
• Where: PLDI
• Authors: Venkatesh Srinivasan, Thomas W. Reps
• Keywords: PLDI 2015, Programming Languages