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Comments (18)

• flohofwoe
  Worth mentioning that MeshOptimizer (https://github.com/zeux/meshoptimizer) has become one of a handful 'hidden champion' pillar libraries that probably carries half of the gaming industry.Basically the curl of asset pipelines ;)https://github.com/zeux/meshoptimizer/discussions/986
• MaskRay
  While we could utilize zigzag encoding (i>>31) ^ (i<<1) to convert SLEB128-encoded type/addend to use ULEB128 instead, the generate code is inferior to or on par with SLEB128 for one-byte encodings on x86, AArch64, and RISC-V. Haven't tried wider values - but zigzag encoding is likely slower as well// One-byte case for SLEB128 int64_t from_signext(uint64_t v) { return v < 64 ? v - 128 : v; }// One-byte case for ULEB128 with zig-zag encoding int64_t from_zigzag(uint64_t z) { return (z >> 1) ^ -(z & 1); }
• fc417fc802
  Is the matrix for bit shifting upside down or am I momentarily making a really dumb mistake here? Edit: nvm I missed the footnote which clarifies that for whatever reason the instruction populates the matrix from bottom to top.
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  londons_explore
  This sort of analysis is great.Now why can't compilers do this sort of thing automatically?Almost any problem seems to be possible to speed up 1000x in AVX512+days of thought compared to the naive version written in a python loop. If we could automate that whole process for big codebases the performance gains could be huge.