Summary: Construction of a Semantic Model
for a Typed Assembly Language
Gang Tan, Andrew W. Appel, Kedar N. Swadi, and Dinghao Wu
Department of Computer Science
Abstract. Typed Assembly Languages (TALs) can be used to validate the safety
of assembly-language programs. However, typing rules are usually trusted as ax-
ioms. In this paper, we show how to build semantic models for typing judgments
in TALs based on an induction technique, so that both the type-safety theorem
and the typing rules can be proved as lemmas in a simple logic. We demonstrate
this technique by giving a complete model to a sample TAL. This model allows
a typing derivation to be interpreted as a machine-checkable safety proof at the
Safety properties of machine code are of growing concern in both industry and academia.
If machine code is compiled from a safe source language, compiler verification can en-
sure the safety of the machine code. However, it is generally prohibitive to do verifica-
tion on an industrial-strength compiler due to its size and complexity.
In this paper, we do validation directly on machine code. Necula introduced Proof-