Expose AVX512 variants of SSE-SSE4.2 instructions

[tannergooding]

This exposes 512-bit variants of all the relevant SSE-SSE4.2 instructions making progress towards completing:

• Expose System.Runtime.Intrinsics.X86.Avx512F.VL #74813
• Expose System.Runtime.Intrinsics.X86.Avx512F #73604
• Expose AVX512BW, AVX512CD, and AVX512DQ #76579

For a few instructions, there is a new Q variant of the instruction that supports 64-bit elements. Where relevant, existing code paths were updated to utilize this instruction

The breakdown of the changes are:

• JIT: +395, -44
  • +84 of this is the main table, the rest is minor updates for specialized handling
• LIB: +2386, -347
  • +225 of this is the reference assembly
  • +1302 lines is the "duplicated" entries for the *.PlatformNotSupported.cs version of the file
  • +1712 lines of this is doc comments (split between the *.cs and *.PlatformNotSupported.cs)
• TST: +10684, -570
  • +392 lines of this is the main table used to generate the tests
  • +10292 lines is csproj and manual tests where they aren't templated yet today

[dotnet-issue-labeler]

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Issue Details

---

This exposes 512-bit variants of all the relevant SSE-SSE4.2 instructions making progress towards completing:

• Expose System.Runtime.Intrinsics.X86.Avx512F.VL #74813
• Expose System.Runtime.Intrinsics.X86.Avx512F #73604
• Expose AVX512BW, AVX512CD, and AVX512DQ #76579

For a few instructions, there is a new Q variant of the instruction that supports 64-bit elements. Where relevant, existing code paths were updated to utilize this instruction

The breakdown of the changes are:

• JIT: +395, -44
  • +84 of this is the main table, the rest is minor updates for specialized handling
• LIB: +2386, -347
  • +225 of this is the reference assembly
  • +1302 lines is the "duplicated" entries for the *.PlatformNotSupported.cs version of the file
  • +1712 lines of this is doc comments (split between the *.cs and *.PlatformNotSupported.cs)
• TST: +10684, -570
  • +392 lines of this is the main table used to generate the tests
  • +10292 lines is csproj and manual tests where they aren't templated yet today

Author:	tannergooding
Assignees:	tannergooding
Labels:	area-CodeGen-coreclr, new-api-needs-documentation
Milestone:	-

[tannergooding]

CC. @dotnet/avx512-contrib, @dotnet/jit-contrib, @dotnet/area-system-runtime-intrinsics

[tannergooding]

Diffs

We see a TP improvement of -0.02% in a couple contexts and codegen improvements for others. The codegen improvements come from:

• containment for things like 256-bit pshufb
• utilizing new the instructions that work with 64-bit elements (such as vpmaxsq)

Linux shows a couple regressions in some of the "recursive implementations" for the Avx.Shuffle and Avx2.AlignRight APIs.

Such diffs come from us supporting containment where we didn't previously and that hoisting the load into the jump table fallback.

We can/should probably avoid containment in the case we need to generate such a jump table, but its a pre-existing condition for all such nodes, so we can handle it in a follow up PR (#84933).

[EgorBo]

JIT and BCL changes LGTM, I skimmed through the tests and they also look ok

[tannergooding]

Tests are passing, but timing out. I have up #84948 to try and help solve some of that.

[steveharter]

Suggested change

	using (TestTable<short> intTable = new TestTable<short>(new short[32] { 1, -5, 100, 0, 1, 2, 3, 4, 1, -5, 100, 0, 1, 2, 3, 4, 1, -5, 100, 0, 1, 2, 3, 4, 1, -5, 100, 0, 1, 2, 3, 4 }, new short[32]))
	using (TestTable<short> intTable = new(new short[32] { 1, -5, 100, 0, 1, 2, 3, 4, 1, -5, 100, 0, 1, 2, 3, 4, 1, -5, 100, 0, 1, 2, 3, 4, 1, -5, 100, 0, 1, 2, 3, 4 }, new short[32]))

a bit more terse; here and elsewhere

[tannergooding]

This is setup in a way that makes it easier to switch to generated from a template in the future.

[tannergooding]

Pulled in #84948 to help resolve test timeouts...

Edit: It did not resolve the timeouts, seems merged test wrappers are more special than we thought. I've pulled in #84959 instead after validating that CI is indeed filtering the tests down on the relevant platforms now.

[steveharter]

LGTM pending green CI

[tannergooding]

Resolved merge conflicts. Should pass now that the tests are properly getting filtered and last run showed OSX got past the timeouts, etc.