William Ashley

asm_volatile_pause: use isb on aarch64

1

Summary: On aarch64, we've found ```isb``` to be a better analogue to the x86 ```pause``` instruction. The ```SpinLock.TryLock``` test/microbenchmark shows a one to two order-of-magnitude reduction in runtime (its runtime...

Fix folly::__folly_memcpy on non-AVX2 platforms

4

**Important note:** I decided to resolve this by making the non-AVX2 case match AVX2, since there had been significant investment in assembly and unit test code towards that behavior, versus...

Adjust TimeseriesHistogram.Percentile test to avoid failing when compiled with FMA

5

Summary: On aarch64, the release build (at least with GCC 11) is using a fused-multiply-add in ```HistogramBuckets::getPercentileEstimate```. One particular evaluation in this test was unfortunately hitting an edge case where...

Fix cache_locality_test.Getcpu.VdsoGetcpu on aarch64

4

Summary: ```Getcpu::resolveVdsoFunc()``` will return null when the vdso does not contain the function ```__vdso_getcpu```, which it does only on x86_64. The test was assuming a non-null return, resulting in segfaults...