Removed usage of BMI2 pdep with SSE2 alternative #19009
Merged
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Description
Replaced
Bmi2.ParallelBitDeposit
with SSE2 alternative.pdep
has bad perf on AMD, so this issue can be sailed aroundAddresses #18949
Benchmarks
Code
For the benchmarks the vectorized path are disabled, so only sequential processing is performed, to have better figures for replacing BMI2. With the vectorized path only the "remainder" is processed by BMI2, so the gain won't be as huge.
I don't have access to any AMD machine, so can't run a benchmark for this.
But according to the results from the runtime-repo for a similar change, this should be a huge boost for AMD-machines.