With the ever-increasing complexity of electronic systems and the increasing extent to which they are used, ensuring the quality of their design is critical. To address this issue, Bryant developed efficient algorithms based on ordered binary decision diagrams (OBDDs) to manipulate the logic functions that form the basis for computer designs. His work revolutionized the field, enabling reasoning about large-scale circuit designs for the first time.
Earlier in his career, Bryant developed the MOSSIM switch-level simulator, the first tool that could model the behavior of very large-scale integrated (VLSI) circuits. Major companies used this tool and continue to use succeeding versions to simulate microprocessors and other complex systems.
Over time, Bryant’s focus shifted from simulation to formal verification, where the design is shown to operate correctly under all possible conditions. It was in this context that he developed the algorithms based on binary demission diagrams. Today it is standard practice for hardware engineers to use OBDD-based equivalence checkers.
Bryant’s OBDD data structure provides a way to represent and reason about Boolean functions. OBDDs form the computational basis for tools that perform hardware and software verification, logic circuit synthesis, circuit test generation and artificial intelligence planning.
In his 22 years at CMU, Bryant also has developed ways to simulate a circuit using symbolic variables to encode the its bit-level signals. More recently, he has been developing formal verification techniques that use more abstract representations of circuit behavior, an approach that can handle much larger and more complex systems. Bryant’s work has resulted in the production of more reliable computing platforms with far-reaching economic and scientific implications.
An IEEE Fellow, Bryant earned his B.S. degree from the University of Michigan’s College of Engineering and a doctoral degree from the Massachusetts Institute of Technology.
