Hi Andrew, On 29-11-2016 13:35, Andrew Haley wrote: > On 29/11/16 09:41, Volker Simonis wrote: >> Thanks Gustavo, >> >> the change looks good. >> >> So now we're just waiting for another review from somebody of the aarch64 >> folks. >> Once we have that and the fc-request is approved I'll push the changes. > > One thing I don't understand: > > cos 0.17098435541865692 1m7.433s 0.1709843554185943 0m56.678s > sin 1.7136493465700289 1m10.654s 1.7136493465700542 0m57.114s > > Do you know what causes the lower digits to be different? Is > it that Math and StrictMath use different algorithms, not just > different optimization levels?
I don't know exactly what's the root cause for that difference (in the result). The difference is not present on x64, however on PPC64 even with -O0 (as it is by now) that difference exists. Math methods are intrisified, but StricMath are not. But I understand that Math and StrictMath share the fdlibm code since I already changed some code in fdlibm that reflected both on Math and StrictMath, so it's not clear to me where the Math relaxation occurs on PPC64 (given that such a relaxation is allowed [1]). For sure others much more experienced than I can comment about difference. Regards, Gustavo [1] https://docs.oracle.com/javase/8/docs/api/java/lang/Math.html
