Evaluation of IEEE 754 floating-point arithmetic compliance across a wide range of heterogeneous computers

Abstract

Scientific applications rely heavily on floating-point arithmetic and, therefore, are affected by the precision and implementation of floating-point operations. Although the computers we use are IEEE compliant, this only assures the same representation of floating-point numbers; it does not guarantee that floating-point operations will be performed in the same way on all computers. As a result the same program run on different computers may yield different results. This paper is a first step in understanding the reason for this, in particular, different results for the execution of the application Charmm on different computers. We report on our use of a well-known test suite, IeeeCC754, to evaluate IEEE 754 compliance across a wide range of heterogeneous computers with different architectures, operating systems, precisions, and compilers.