Make LEB128 size calculation branchless #29
Merged
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I saw this library being references in the C# reimplementation of ObjWriter for ILC/NativeAOT and I noticed the ULEB128 calculations which I knew neat trick for. I learned this trick from Google's AOSP source some years back and been using it since in my own libs.
It usesSystem.Numerics.BitOperations.LeadingZeroCount
, which is not in .NET Standard but is supported from .NET Core 3 and up which also is the lowest supported TFM in .NET Standard 2.1. This is why I added it as TFM to csproj.edit: Thanks to targeting .NET 7, we can call
BitOperations.LeadingZeroCount
directly 🎉x86 Codegen (.NET 7.0)
SizeOfULEB128
SizeOfILEB128
This is pretty obscure bit-twiddling hack that I understand completely if it's too much of an premature optimization/hack for this library, just testing waters. 😄