Scatter Plots for x86 FPU Error Data

These plots were with gnuplot 4.6 and data gathered using the included utility. First run gather-data.bat to generate data files. Then run plot.bat to make the plots. The argument ranges chosen are based on Appendix G of the 1995 Pentium Processor Family Developer’s Manual Volume 3: Architecture and Programming Manual (download). Additional ranges of interest are included.

Here are the results from Intel Core i7-2600 and AMD A6-3650. The AMD transcendental instructions have behavior similar to those found in Intel processors, though the non-trig AMD transcendental instructions are slightly more accurate.