Update the x86 hwintrinsic list to match the arm64 layout #35364
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CC. @echesakovMSFT, @CarolEidt |
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LGTM (minus one suggestion about using curly braces in switch-case-s).
@tannergooding I am planning to remove UnfixedSIMDSize flag - I believe JIT can infer if the SIMD size is arbitrary from -1 in the "SIMD size" column? Do you have any objections?
| case NI_SSE2_CompareEqual: | ||
| case NI_SSE2_CompareScalarEqual: | ||
| case NI_AVX_CompareEqual: | ||
| { |
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Why to put curly braces around simple return statement? They are not needed here, they do not increase readability and I don't believe we use them in other places in the JIT. cc @dotnet/jit-contrib
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Habit mostly. It minimizes the diff if inserting additional code and allows the block to be collapsed in an IDE.
Sounds fine to me. There are a few places we can improve this further and we can even likely use the |
I had this idea in mind - it would simplify implementation of some of the intrinsics where the simd size controls what instruction to emit (e.g. AddWideningLower (baseType is first arg's type) - for SIMD8 emit addl for SIMD16 emit addw). However, I would postpone such change for now and implement these as SpecialCodeGen . |
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As commented on #35030 (comment), there are relatively few intrinsics that actually take a hardcoded immediate value on x86 and none on ARM64. Since there are so few intrinsics, roughly 6% (4-bytes) of each
HWIntrinsicInfoentry was going unused, spread out across the ~480 entries, this was almost 2kb.Given the above, this removes the
ivalentry from the x86 intrinsic list and changes it to be a simple switch table lookup instead. Additionally, since the table entries were being updated anyways, this adjusts the ordering to match what we were doing on ARM64 so that we only need to provide the isa and method name which are used to construct the ID.