Add support for some more simd folding to improve the new IndexOf and related helpers #117572
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CC. @dotnet/jit-contrib Fixes some codegen issues that @EgorBo saw. Going to have a follow up PR that better improves the Arm64 handling by ensuring that |
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/azp run Fuzzlyn |
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Fuzzlyn issue is #117605 |
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/ba-g unrelated android timeouts |
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This handles cases like
Vector128.IndexOfWhereAllBitsSet(Vector128.Equals(x, y))and ensures we get more optimal codegen.; Method ClassLibrary2.Class1:M(System.Runtime.Intrinsics.Vector128`1[int],System.Runtime.Intrinsics.Vector128`1[int]):int (FullOpts) G_M000_IG01: ;; offset=0x0000 G_M000_IG02: ;; offset=0x0000 C5F81001 vmovups xmm0, xmmword ptr [rcx] C5F97602 vpcmpeqd xmm0, xmm0, xmmword ptr [rdx] - C5F176C9 vpcmpeqd xmm1, xmm1, xmm1 - C5F176C0 vpcmpeqd xmm0, xmm1, xmm0 C5F850C0 vmovmskps rax, xmm0 F30FBCC0 tzcnt eax, eax B9FFFFFFFF mov ecx, -1 83F820 cmp eax, 32 0F44C1 cmove eax, ecx G_M000_IG03: ;; offset=0x0023 C3 ret ; Total bytes of code: 36This mostly stems from ensuring that
Compare(mask, AllBitsSet)andCompare(mask, Zero)are handled. However, it also found some cases where we weren't foldingTrailingZeroCount,ReverseElementBits, orPopCountwhich are used by the new helpers and so ensures those are handled as well.