HP-UX Floating-Point Guide

Chapter 7 191

Performance Tuning

Quad-Precision Computations

Computations involving quad-precision operands are inherently much

slower than those involving double-precision or single-precision

operands. The reason is that HP 9000 hardware supports only

single-precision and double-precision operations. All quad-precision

operations, even the simplest arithmetic ones, are performed in software.

For this reason, you should use quad-precision for performance-sensitive

code only if your application absolutely requires this degree of precision.