Formal Verification of Floating-Point RTL at AMD Using the ACL2 Theorem Prover

We describe a methodology for the formal verification of the correctness, including IEEE-compliance, of register-transfer level models of floating-point hardware designs, and its application to the floating-point units of a series of commercial microprocessors produced by Advanced Micro Devices, Inc. The methodology is based on a mechanical translator from a synthesizable subset of the Verilog hardware description language, in which the models are coded, to the formal logic of the ACL2 theorem prover. Behavioral specifications of correctness, coded in essentially the same language as the designs, are translated as well, and ultimately checked with the ACL2 prover. Keywords— Formal verification, Floating-point arithmetic, IEEE-compliance, Theorem proving, ACL2