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Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T> #92261

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#92282
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Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T>#92261
#92282
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area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMIavx512Related to the AVX-512 architecture

Description

@MineCake147E
MineCake147E
opened on Sep 19, 2023

Description

When I was playing with the Vector512<T>, I found some inconsistent behavior of + operator for Vector512<byte>, depending on one or more arguments being generated by Vector512.Equals or not.

Both the .NET 7 and .NET 8 RC 1 are doing the right thing for Vector256<byte>:

[MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));

In .NET 7, it generates:

vzerouppermovrax,qword ptr [rsp+28h]vmovupdymm0,ymmword ptr [rdx]vmovupdymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovupd ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret

In .NET 8 RC 1, it generates:

vzerouppermovrax,qword ptr [rsp+28h]vmovupsymm0,ymmword ptr [rdx]vmovupsymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovups ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret

But when it comes to Vector512<byte>, it somehow goes wrong.

[MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));

In .NET 8 RC 1, it generates:

vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 ; WRONG INSTRUCTION!vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret

While what I expect it to generate looks like:

vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret

And even weirder, if I add Vector512<byte>.Zero in advance of adding second operand, like:

[MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));

It generates what I expect it to generate from Test512Blend:

vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret

Adding the Vector512<T>.Zero MUST NOT alter the result of the whole integer + operation.

Reproduction Steps

  1. Obtain a JIT assembly for the codes below with .NET 8 RC 1:
[MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));
[MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
[MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));

Expected behavior

The code:

[MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));

and

[MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));

For both functions, it should generate something like:

vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret

Actual behavior

For the code:

[MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));

It instead generates something like:

vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret

Regression?

Unknown

Known Workarounds

By adding Vector512<T>.Zero in advance of adding second operand, like:

[MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));

It generates:

vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret

Configuration

  • .NET version: 8.0.100-rc.1.23455.8
  • PC: Custom built PC
    • OS: Windows 11 Home 22H2 (22621.2283)
    • CPU: Intel(R) Xeon(R) w5-2455X 3.19 GHz
    • RAM: 32 GB DDR5 ECC RDIMM
    • Graphics: NVIDIA GeForce GTX1060(6 GB)
    • Storage:
      • OS(C:) : WD_BLACK SN770 1TB PCIe 4.0 NVMe M.2 SSD
      • DATA (D:) : Western Digital WDC WD10EZEX-22MFCA0 1000.2 GB 7200RPM SATA HDD
      • WORKSPACE (E:) : Seagate ST1000DM003-1ER162 1000.2 GB 7200RPM SATA HDD
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Inconsistent and counterintuitive codegen behavior of `+` operator for `Vector512<T>` depending on the number and order of operands generated by compare instructions, unlike for `Vector256<T>` · Issue #92261 · dotnet/runtime · GitHub
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      Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T> #92261
      Closed
      #92282
      Closed
      Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T>#92261
      #92282
      Labels
      area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMIavx512Related to the AVX-512 architecture
      Description
      @MineCake147E
      MineCake147E
      opened on Sep 19, 2023
      Description
      When I was playing with the Vector512<T>, I found some inconsistent behavior of + operator for Vector512<byte>, depending on one or more arguments being generated by Vector512.Equals or not.
      Both the .NET 7 and .NET 8 RC 1 are doing the right thing for Vector256<byte>:
      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));
      In .NET 7, it generates:
      vzerouppermovrax,qword ptr [rsp+28h]vmovupdymm0,ymmword ptr [rdx]vmovupdymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovupd ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret
      In .NET 8 RC 1, it generates:
      vzerouppermovrax,qword ptr [rsp+28h]vmovupsymm0,ymmword ptr [rdx]vmovupsymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovups ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret
      But when it comes to Vector512<byte>, it somehow goes wrong.
      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
      In .NET 8 RC 1, it generates:
      vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 ; WRONG INSTRUCTION!vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
      While what I expect it to generate looks like:
      vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
      And even weirder, if I add Vector512<byte>.Zero in advance of adding second operand, like:
      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
      It generates what I expect it to generate from Test512Blend:
      vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
      Adding the Vector512<T>.Zero MUST NOT alter the result of the whole integer + operation.
      Reproduction Steps
      1. Obtain a JIT assembly for the codes below with .NET 8 RC 1:
      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));
      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
      Expected behavior
      The code:
      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
      and
      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
      For both functions, it should generate something like:
      vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
      Actual behavior
      For the code:
      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
      It instead generates something like:
      vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
      Regression?
      Unknown
      Known Workarounds
      By adding Vector512<T>.Zero in advance of adding second operand, like:
      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
      It generates:
      vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
      Configuration
      • .NET version: 8.0.100-rc.1.23455.8
      • PC: Custom built PC

        • OS: Windows 11 Home 22H2 (22621.2283)
        • CPU: Intel(R) Xeon(R) w5-2455X 3.19 GHz
        • RAM: 32 GB DDR5 ECC RDIMM
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          • OS(C:) : WD_BLACK SN770 1TB PCIe 4.0 NVMe M.2 SSD
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          • WORKSPACE (E:) : Seagate ST1000DM003-1ER162 1000.2 GB 7200RPM SATA HDD
      
Visual Studio 2022 installation

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      Code Cleanup On Save 1.0.12
      
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      Common Azure Tools 1.10
      
Provides common services for use by Azure Mobile Services and Microsoft Azure Tools.
      Extensibility Message Bus 1.4.39 (main@e8108eb)
      
Provides common messaging-based MEF services for loosely coupled Visual Studio extension components communication and integration.
      File Icons 2.7
      
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      Microsoft JVM Debugger 1.0
      
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      NuGet パッケージ マネージャー 6.8.0
      
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      Razor (ASP.NET Core) 17.8.2.2345506+ade90399d42c1a7bf92191b1c067816c0ae1c311
      
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      SonarLint for Visual Studio 7.3.0.77872
      
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      Tweaks 2022 1.1.143
      
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      TypeScript Tools 17.0.20830.2001
      
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      Xamarin Templates 17.8.16 (830b56a)
      
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Inconsistent and counterintuitive codegen behavior of `+` operator for `Vector512<T>` depending on the number and order of operands generated by compare instructions, unlike for `Vector256<T>` · Issue #92261 · dotnet/runtime · GitHub
          Skip to content
          Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T> #92261
          Closed
          #92282
          Closed
          Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T>#92261
          #92282
          Labels
          area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMIavx512Related to the AVX-512 architecture
          Description
          @MineCake147E
          MineCake147E
          opened on Sep 19, 2023
          Description
          When I was playing with the Vector512<T>, I found some inconsistent behavior of + operator for Vector512<byte>, depending on one or more arguments being generated by Vector512.Equals or not.
          Both the .NET 7 and .NET 8 RC 1 are doing the right thing for Vector256<byte>:
          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));
          In .NET 7, it generates:
          vzerouppermovrax,qword ptr [rsp+28h]vmovupdymm0,ymmword ptr [rdx]vmovupdymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovupd ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret
          In .NET 8 RC 1, it generates:
          vzerouppermovrax,qword ptr [rsp+28h]vmovupsymm0,ymmword ptr [rdx]vmovupsymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovups ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret
          But when it comes to Vector512<byte>, it somehow goes wrong.
          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
          In .NET 8 RC 1, it generates:
          vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 ; WRONG INSTRUCTION!vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
          While what I expect it to generate looks like:
          vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
          And even weirder, if I add Vector512<byte>.Zero in advance of adding second operand, like:
          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
          It generates what I expect it to generate from Test512Blend:
          vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
          Adding the Vector512<T>.Zero MUST NOT alter the result of the whole integer + operation.
          Reproduction Steps
          1. Obtain a JIT assembly for the codes below with .NET 8 RC 1:
          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));
          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
          Expected behavior
          The code:
          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
          and
          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
          For both functions, it should generate something like:
          vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
          Actual behavior
          For the code:
          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
          It instead generates something like:
          vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
          Regression?
          Unknown
          Known Workarounds
          By adding Vector512<T>.Zero in advance of adding second operand, like:
          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
          It generates:
          vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
          Configuration
          • .NET version: 8.0.100-rc.1.23455.8
          • PC: Custom built PC

            • OS: Windows 11 Home 22H2 (22621.2283)
            • CPU: Intel(R) Xeon(R) w5-2455X 3.19 GHz
            • RAM: 32 GB DDR5 ECC RDIMM
            • Graphics: NVIDIA GeForce GTX1060(6 GB)
            • Storage:

              • OS(C:) : WD_BLACK SN770 1TB PCIe 4.0 NVMe M.2 SSD
              • DATA (D:) : Western Digital WDC WD10EZEX-22MFCA0 1000.2 GB 7200RPM SATA HDD
              • WORKSPACE (E:) : Seagate ST1000DM003-1ER162 1000.2 GB 7200RPM SATA HDD
          
Visual Studio 2022 installation

          Microsoft Visual Studio Community 2022
          
Version 17.8.0 Preview 2.0
          
VisualStudio.17.Preview/17.8.0-pre.2.0+34112.27
          
Microsoft .NET Framework
          
Version 4.8.09032
          インストールされているバージョン:Community
          Visual C++ 2022 00482-90000-00000-AA248
          
Microsoft Visual C++ 2022
          ASP.NET and Web Tools 17.8.226.21692
          
ASP.NET and Web Tools
          AvaloniaPackage Extension 1.0
          
AvaloniaPackage Visual Studio Extension Detailed Info
          Azure App Service Tools v3.0.0 17.8.226.21692
          
Azure App Service Tools v3.0.0
          Azure Functions and Web Jobs Tools 17.8.226.21692
          
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          C# ツール 4.8.0-2.23429.7+44555193fd1135b5d53a2099f76fec91e0d1ebde
          
IDE で使用する C# コンポーネント。プロジェクトの種類や設定に応じて、異なるバージョンのコンパイラを使用できます。
          Code Cleanup On Save 1.0.12
          
Automatically run one of the Code Clean profiles when saving the document. This ensures your code is always formatted correctly and follows your coding style conventions.
          Common Azure Tools 1.10
          
Provides common services for use by Azure Mobile Services and Microsoft Azure Tools.
          Extensibility Message Bus 1.4.39 (main@e8108eb)
          
Provides common messaging-based MEF services for loosely coupled Visual Studio extension components communication and integration.
          File Icons 2.7
          
Adds icons for files that are not recognized by Solution Explorer
          Microsoft JVM Debugger 1.0
          
Provides support for connecting the Visual Studio debugger to JDWP compatible Java Virtual Machines
          Mono Debugging for Visual Studio 17.8.14 (0c9914e)
          
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          NuGet パッケージ マネージャー 6.8.0
          
Visual Studio 内の NuGet パッケージ マネージャー。NuGet の詳細については、https://docs.nuget.org/ にアクセスしてください
          Razor (ASP.NET Core) 17.8.2.2345506+ade90399d42c1a7bf92191b1c067816c0ae1c311
          
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          SonarLint for Visual Studio 7.3.0.77872
          
SonarLint is an extension to your favorite IDE that provides on-the-fly feedback to developers on new bugs and quality issues injected into their code.
          SQL Server Data Tools 17.8.64.0
          
Microsoft SQL Server Data Tools
          Tweaks 2022 1.1.143
          
A collection of minor fixes and tweaks for Visual Studio to reduce the paper cuts and make you a happier developer
          TypeScript Tools 17.0.20830.2001
          
TypeScript Tools for Microsoft Visual Studio
          Visual Basic ツール 4.8.0-2.23429.7+44555193fd1135b5d53a2099f76fec91e0d1ebde
          
IDE で使用する Visual Basic コンポーネント。プロジェクトの種類や設定に応じて、異なるバージョンのコンパイラを使用できます。
          Visual F# Tools 17.8.0-beta.23425.10+0d3549fa5b8b6387ade191d76768405cefed8229
          
Microsoft Visual F# Tools
          Visual Studio IntelliCode 2.2
          
Visual Studio 向けの AI 支援付き開発。
          VisualStudio.DeviceLog 1.0
          
パッケージに関する情報
          VisualStudio.Mac 1.0
          
Mac Extension for Visual Studio
          Xamarin 17.8.0.118 (main@35c256f)
          
Xamarin.iOS と Xamarin.Android の開発を有効にする Visual Studio 拡張機能
          Xamarin Designer 17.8.1.11 (remotes/origin/d17-8@13ef934098)
          
Visual Studio で Xamarin Designer ツールを有効にするための Visual Studio 拡張機能。
          Xamarin Templates 17.8.16 (830b56a)
          
Templates for building iOS, Android, and Windows apps with Xamarin and Xamarin.Forms.
          Xamarin.Android SDK 13.2.1.2 (d17-5/a8a26c7)
          
Xamarin.Android Reference Assemblies and MSBuild support.
          
Mono: d9a6e87
          
Java.Interop: xamarin/java.interop/d17-5@149d70fe
          
SQLite: xamarin/sqlite@68c69d8
          
Xamarin.Android Tools: xamarin/xamarin-android-tools/d17-5@ca1552d
          Xamarin.iOS and Xamarin.Mac SDK 16.4.0.16 (b5972410d)
          
Xamarin.iOS and Xamarin.Mac Reference Assemblies and MSBuild support.
          Other information
          No response
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Inconsistent and counterintuitive codegen behavior of `+` operator for `Vector512<T>` depending on the number and order of operands generated by compare instructions, unlike for `Vector256<T>` · Issue #92261 · dotnet/runtime · GitHub
              Skip to content
              Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T> #92261
              Closed
              #92282
              Closed
              Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T>#92261
              #92282
              Labels
              area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMIavx512Related to the AVX-512 architecture
              Description
              @MineCake147E
              MineCake147E
              opened on Sep 19, 2023
              Description
              When I was playing with the Vector512<T>, I found some inconsistent behavior of + operator for Vector512<byte>, depending on one or more arguments being generated by Vector512.Equals or not.
              Both the .NET 7 and .NET 8 RC 1 are doing the right thing for Vector256<byte>:
              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));
              In .NET 7, it generates:
              vzerouppermovrax,qword ptr [rsp+28h]vmovupdymm0,ymmword ptr [rdx]vmovupdymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovupd ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret
              In .NET 8 RC 1, it generates:
              vzerouppermovrax,qword ptr [rsp+28h]vmovupsymm0,ymmword ptr [rdx]vmovupsymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovups ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret
              But when it comes to Vector512<byte>, it somehow goes wrong.
              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
              In .NET 8 RC 1, it generates:
              vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 ; WRONG INSTRUCTION!vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
              While what I expect it to generate looks like:
              vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
              And even weirder, if I add Vector512<byte>.Zero in advance of adding second operand, like:
              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
              It generates what I expect it to generate from Test512Blend:
              vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
              Adding the Vector512<T>.Zero MUST NOT alter the result of the whole integer + operation.
              Reproduction Steps
              1. Obtain a JIT assembly for the codes below with .NET 8 RC 1:
              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));
              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
              Expected behavior
              The code:
              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
              and
              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
              For both functions, it should generate something like:
              vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
              Actual behavior
              For the code:
              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
              It instead generates something like:
              vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
              Regression?
              Unknown
              Known Workarounds
              By adding Vector512<T>.Zero in advance of adding second operand, like:
              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
              It generates:
              vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
              Configuration
              • .NET version: 8.0.100-rc.1.23455.8
              • PC: Custom built PC

                • OS: Windows 11 Home 22H2 (22621.2283)
                • CPU: Intel(R) Xeon(R) w5-2455X 3.19 GHz
                • RAM: 32 GB DDR5 ECC RDIMM
                • Graphics: NVIDIA GeForce GTX1060(6 GB)
                • Storage:

                  • OS(C:) : WD_BLACK SN770 1TB PCIe 4.0 NVMe M.2 SSD
                  • DATA (D:) : Western Digital WDC WD10EZEX-22MFCA0 1000.2 GB 7200RPM SATA HDD
                  • WORKSPACE (E:) : Seagate ST1000DM003-1ER162 1000.2 GB 7200RPM SATA HDD
              
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1) {
if (node.tagName === 'A') cleanLinks();
node.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '
Inconsistent and counterintuitive codegen behavior of `+` operator for `Vector512<T>` depending on the number and order of operands generated by compare instructions, unlike for `Vector256<T>` · Issue #92261 · dotnet/runtime · GitHub
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                  Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T> #92261
                  Closed
                  #92282
                  Closed
                  Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T>#92261
                  #92282
                  Labels
                  area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMIavx512Related to the AVX-512 architecture
                  Description
                  @MineCake147E
                  MineCake147E
                  opened on Sep 19, 2023
                  Description
                  When I was playing with the Vector512<T>, I found some inconsistent behavior of + operator for Vector512<byte>, depending on one or more arguments being generated by Vector512.Equals or not.
                  Both the .NET 7 and .NET 8 RC 1 are doing the right thing for Vector256<byte>:
                  [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));
                  In .NET 7, it generates:
                  vzerouppermovrax,qword ptr [rsp+28h]vmovupdymm0,ymmword ptr [rdx]vmovupdymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovupd ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret
                  In .NET 8 RC 1, it generates:
                  vzerouppermovrax,qword ptr [rsp+28h]vmovupsymm0,ymmword ptr [rdx]vmovupsymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovups ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret
                  But when it comes to Vector512<byte>, it somehow goes wrong.
                  [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                  In .NET 8 RC 1, it generates:
                  vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 ; WRONG INSTRUCTION!vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                  While what I expect it to generate looks like:
                  vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                  And even weirder, if I add Vector512<byte>.Zero in advance of adding second operand, like:
                  [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                  It generates what I expect it to generate from Test512Blend:
                  vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                  Adding the Vector512<T>.Zero MUST NOT alter the result of the whole integer + operation.
                  Reproduction Steps
                  1. Obtain a JIT assembly for the codes below with .NET 8 RC 1:
                  [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));
                  [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                  [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                  Expected behavior
                  The code:
                  [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                  and
                  [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                  For both functions, it should generate something like:
                  vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                  Actual behavior
                  For the code:
                  [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                  It instead generates something like:
                  vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                  Regression?
                  Unknown
                  Known Workarounds
                  By adding Vector512<T>.Zero in advance of adding second operand, like:
                  [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                  It generates:
                  vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                  Configuration
                  • .NET version: 8.0.100-rc.1.23455.8
                  • PC: Custom built PC

                    • OS: Windows 11 Home 22H2 (22621.2283)
                    • CPU: Intel(R) Xeon(R) w5-2455X 3.19 GHz
                    • RAM: 32 GB DDR5 ECC RDIMM
                    • Graphics: NVIDIA GeForce GTX1060(6 GB)
                    • Storage:

                      • OS(C:) : WD_BLACK SN770 1TB PCIe 4.0 NVMe M.2 SSD
                      • DATA (D:) : Western Digital WDC WD10EZEX-22MFCA0 1000.2 GB 7200RPM SATA HDD
                      • WORKSPACE (E:) : Seagate ST1000DM003-1ER162 1000.2 GB 7200RPM SATA HDD
                  
Visual Studio 2022 installation

                  Microsoft Visual Studio Community 2022
                  
Version 17.8.0 Preview 2.0
                  
VisualStudio.17.Preview/17.8.0-pre.2.0+34112.27
                  
Microsoft .NET Framework
                  
Version 4.8.09032
                  インストールされているバージョン:Community
                  Visual C++ 2022 00482-90000-00000-AA248
                  
Microsoft Visual C++ 2022
                  ASP.NET and Web Tools 17.8.226.21692
                  
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                  Code Cleanup On Save 1.0.12
                  
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                  Common Azure Tools 1.10
                  
Provides common services for use by Azure Mobile Services and Microsoft Azure Tools.
                  Extensibility Message Bus 1.4.39 (main@e8108eb)
                  
Provides common messaging-based MEF services for loosely coupled Visual Studio extension components communication and integration.
                  File Icons 2.7
                  
Adds icons for files that are not recognized by Solution Explorer
                  Microsoft JVM Debugger 1.0
                  
Provides support for connecting the Visual Studio debugger to JDWP compatible Java Virtual Machines
                  Mono Debugging for Visual Studio 17.8.14 (0c9914e)
                  
Support for debugging Mono processes with Visual Studio.
                  NuGet パッケージ マネージャー 6.8.0
                  
Visual Studio 内の NuGet パッケージ マネージャー。NuGet の詳細については、https://docs.nuget.org/ にアクセスしてください
                  Razor (ASP.NET Core) 17.8.2.2345506+ade90399d42c1a7bf92191b1c067816c0ae1c311
                  
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                  SonarLint for Visual Studio 7.3.0.77872
                  
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                  SQL Server Data Tools 17.8.64.0
                  
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                  Tweaks 2022 1.1.143
                  
A collection of minor fixes and tweaks for Visual Studio to reduce the paper cuts and make you a happier developer
                  TypeScript Tools 17.0.20830.2001
                  
TypeScript Tools for Microsoft Visual Studio
                  Visual Basic ツール 4.8.0-2.23429.7+44555193fd1135b5d53a2099f76fec91e0d1ebde
                  
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                  Visual F# Tools 17.8.0-beta.23425.10+0d3549fa5b8b6387ade191d76768405cefed8229
                  
Microsoft Visual F# Tools
                  Visual Studio IntelliCode 2.2
                  
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                  VisualStudio.Mac 1.0
                  
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                  Xamarin 17.8.0.118 (main@35c256f)
                  
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                  Xamarin Templates 17.8.16 (830b56a)
                  
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                  Xamarin.Android SDK 13.2.1.2 (d17-5/a8a26c7)
                  
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Mono: d9a6e87
                  
Java.Interop: xamarin/java.interop/d17-5@149d70fe
                  
SQLite: xamarin/sqlite@68c69d8
                  
Xamarin.Android Tools: xamarin/xamarin-android-tools/d17-5@ca1552d
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                    area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMIavx512Related to the AVX-512 architecture
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(function(){
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var __m = "*";
var __re = new RegExp('^' + ".*" + '
Inconsistent and counterintuitive codegen behavior of `+` operator for `Vector512<T>` depending on the number and order of operands generated by compare instructions, unlike for `Vector256<T>` · Issue #92261 · dotnet/runtime · GitHub
                      Skip to content
                      Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T> #92261
                      Closed
                      #92282
                      Closed
                      Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T>#92261
                      #92282
                      Labels
                      area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMIavx512Related to the AVX-512 architecture
                      Description
                      @MineCake147E
                      MineCake147E
                      opened on Sep 19, 2023
                      Description
                      When I was playing with the Vector512<T>, I found some inconsistent behavior of + operator for Vector512<byte>, depending on one or more arguments being generated by Vector512.Equals or not.
                      Both the .NET 7 and .NET 8 RC 1 are doing the right thing for Vector256<byte>:
                      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));
                      In .NET 7, it generates:
                      vzerouppermovrax,qword ptr [rsp+28h]vmovupdymm0,ymmword ptr [rdx]vmovupdymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovupd ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret
                      In .NET 8 RC 1, it generates:
                      vzerouppermovrax,qword ptr [rsp+28h]vmovupsymm0,ymmword ptr [rdx]vmovupsymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovups ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret
                      But when it comes to Vector512<byte>, it somehow goes wrong.
                      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                      In .NET 8 RC 1, it generates:
                      vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 ; WRONG INSTRUCTION!vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                      While what I expect it to generate looks like:
                      vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                      And even weirder, if I add Vector512<byte>.Zero in advance of adding second operand, like:
                      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                      It generates what I expect it to generate from Test512Blend:
                      vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                      Adding the Vector512<T>.Zero MUST NOT alter the result of the whole integer + operation.
                      Reproduction Steps
                      1. Obtain a JIT assembly for the codes below with .NET 8 RC 1:
                      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));
                      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                      Expected behavior
                      The code:
                      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                      and
                      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                      For both functions, it should generate something like:
                      vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                      Actual behavior
                      For the code:
                      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                      It instead generates something like:
                      vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                      Regression?
                      Unknown
                      Known Workarounds
                      By adding Vector512<T>.Zero in advance of adding second operand, like:
                      [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                      It generates:
                      vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                      Configuration
                      • .NET version: 8.0.100-rc.1.23455.8
                      • PC: Custom built PC

                        • OS: Windows 11 Home 22H2 (22621.2283)
                        • CPU: Intel(R) Xeon(R) w5-2455X 3.19 GHz
                        • RAM: 32 GB DDR5 ECC RDIMM
                        • Graphics: NVIDIA GeForce GTX1060(6 GB)
                        • Storage:

                          • OS(C:) : WD_BLACK SN770 1TB PCIe 4.0 NVMe M.2 SSD
                          • DATA (D:) : Western Digital WDC WD10EZEX-22MFCA0 1000.2 GB 7200RPM SATA HDD
                          • WORKSPACE (E:) : Seagate ST1000DM003-1ER162 1000.2 GB 7200RPM SATA HDD
                      
Visual Studio 2022 installation

                      Microsoft Visual Studio Community 2022
                      
Version 17.8.0 Preview 2.0
                      
VisualStudio.17.Preview/17.8.0-pre.2.0+34112.27
                      
Microsoft .NET Framework
                      
Version 4.8.09032
                      インストールされているバージョン:Community
                      Visual C++ 2022 00482-90000-00000-AA248
                      
Microsoft Visual C++ 2022
                      ASP.NET and Web Tools 17.8.226.21692
                      
ASP.NET and Web Tools
                      AvaloniaPackage Extension 1.0
                      
AvaloniaPackage Visual Studio Extension Detailed Info
                      Azure App Service Tools v3.0.0 17.8.226.21692
                      
Azure App Service Tools v3.0.0
                      Azure Functions and Web Jobs Tools 17.8.226.21692
                      
Azure Functions and Web Jobs Tools
                      C# ツール 4.8.0-2.23429.7+44555193fd1135b5d53a2099f76fec91e0d1ebde
                      
IDE で使用する C# コンポーネント。プロジェクトの種類や設定に応じて、異なるバージョンのコンパイラを使用できます。
                      Code Cleanup On Save 1.0.12
                      
Automatically run one of the Code Clean profiles when saving the document. This ensures your code is always formatted correctly and follows your coding style conventions.
                      Common Azure Tools 1.10
                      
Provides common services for use by Azure Mobile Services and Microsoft Azure Tools.
                      Extensibility Message Bus 1.4.39 (main@e8108eb)
                      
Provides common messaging-based MEF services for loosely coupled Visual Studio extension components communication and integration.
                      File Icons 2.7
                      
Adds icons for files that are not recognized by Solution Explorer
                      Microsoft JVM Debugger 1.0
                      
Provides support for connecting the Visual Studio debugger to JDWP compatible Java Virtual Machines
                      Mono Debugging for Visual Studio 17.8.14 (0c9914e)
                      
Support for debugging Mono processes with Visual Studio.
                      NuGet パッケージ マネージャー 6.8.0
                      
Visual Studio 内の NuGet パッケージ マネージャー。NuGet の詳細については、https://docs.nuget.org/ にアクセスしてください
                      Razor (ASP.NET Core) 17.8.2.2345506+ade90399d42c1a7bf92191b1c067816c0ae1c311
                      
ASP.NET Core Razor の言語サービスを提供します。
                      SonarLint for Visual Studio 7.3.0.77872
                      
SonarLint is an extension to your favorite IDE that provides on-the-fly feedback to developers on new bugs and quality issues injected into their code.
                      SQL Server Data Tools 17.8.64.0
                      
Microsoft SQL Server Data Tools
                      Tweaks 2022 1.1.143
                      
A collection of minor fixes and tweaks for Visual Studio to reduce the paper cuts and make you a happier developer
                      TypeScript Tools 17.0.20830.2001
                      
TypeScript Tools for Microsoft Visual Studio
                      Visual Basic ツール 4.8.0-2.23429.7+44555193fd1135b5d53a2099f76fec91e0d1ebde
                      
IDE で使用する Visual Basic コンポーネント。プロジェクトの種類や設定に応じて、異なるバージョンのコンパイラを使用できます。
                      Visual F# Tools 17.8.0-beta.23425.10+0d3549fa5b8b6387ade191d76768405cefed8229
                      
Microsoft Visual F# Tools
                      Visual Studio IntelliCode 2.2
                      
Visual Studio 向けの AI 支援付き開発。
                      VisualStudio.DeviceLog 1.0
                      
パッケージに関する情報
                      VisualStudio.Mac 1.0
                      
Mac Extension for Visual Studio
                      Xamarin 17.8.0.118 (main@35c256f)
                      
Xamarin.iOS と Xamarin.Android の開発を有効にする Visual Studio 拡張機能
                      Xamarin Designer 17.8.1.11 (remotes/origin/d17-8@13ef934098)
                      
Visual Studio で Xamarin Designer ツールを有効にするための Visual Studio 拡張機能。
                      Xamarin Templates 17.8.16 (830b56a)
                      
Templates for building iOS, Android, and Windows apps with Xamarin and Xamarin.Forms.
                      Xamarin.Android SDK 13.2.1.2 (d17-5/a8a26c7)
                      
Xamarin.Android Reference Assemblies and MSBuild support.
                      
Mono: d9a6e87
                      
Java.Interop: xamarin/java.interop/d17-5@149d70fe
                      
SQLite: xamarin/sqlite@68c69d8
                      
Xamarin.Android Tools: xamarin/xamarin-android-tools/d17-5@ca1552d
                      Xamarin.iOS and Xamarin.Mac SDK 16.4.0.16 (b5972410d)
                      
Xamarin.iOS and Xamarin.Mac Reference Assemblies and MSBuild support.
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                      No response
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(function(){
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var __m = "*";
var __re = new RegExp('^' + ".*" + '
Inconsistent and counterintuitive codegen behavior of `+` operator for `Vector512<T>` depending on the number and order of operands generated by compare instructions, unlike for `Vector256<T>` · Issue #92261 · dotnet/runtime · GitHub
                          Skip to content
                          Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T> #92261
                          Closed
                          #92282
                          Closed
                          Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T>#92261
                          #92282
                          Labels
                          area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMIavx512Related to the AVX-512 architecture
                          Description
                          @MineCake147E
                          MineCake147E
                          opened on Sep 19, 2023
                          Description
                          When I was playing with the Vector512<T>, I found some inconsistent behavior of + operator for Vector512<byte>, depending on one or more arguments being generated by Vector512.Equals or not.
                          Both the .NET 7 and .NET 8 RC 1 are doing the right thing for Vector256<byte>:
                          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));
                          In .NET 7, it generates:
                          vzerouppermovrax,qword ptr [rsp+28h]vmovupdymm0,ymmword ptr [rdx]vmovupdymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovupd ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret
                          In .NET 8 RC 1, it generates:
                          vzerouppermovrax,qword ptr [rsp+28h]vmovupsymm0,ymmword ptr [rdx]vmovupsymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovups ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret
                          But when it comes to Vector512<byte>, it somehow goes wrong.
                          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                          In .NET 8 RC 1, it generates:
                          vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 ; WRONG INSTRUCTION!vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                          While what I expect it to generate looks like:
                          vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                          And even weirder, if I add Vector512<byte>.Zero in advance of adding second operand, like:
                          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                          It generates what I expect it to generate from Test512Blend:
                          vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                          Adding the Vector512<T>.Zero MUST NOT alter the result of the whole integer + operation.
                          Reproduction Steps
                          1. Obtain a JIT assembly for the codes below with .NET 8 RC 1:
                          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));
                          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                          Expected behavior
                          The code:
                          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                          and
                          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                          For both functions, it should generate something like:
                          vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                          Actual behavior
                          For the code:
                          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                          It instead generates something like:
                          vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                          Regression?
                          Unknown
                          Known Workarounds
                          By adding Vector512<T>.Zero in advance of adding second operand, like:
                          [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                          It generates:
                          vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                          Configuration
                          • .NET version: 8.0.100-rc.1.23455.8
                          • PC: Custom built PC

                            • OS: Windows 11 Home 22H2 (22621.2283)
                            • CPU: Intel(R) Xeon(R) w5-2455X 3.19 GHz
                            • RAM: 32 GB DDR5 ECC RDIMM
                            • Graphics: NVIDIA GeForce GTX1060(6 GB)
                            • Storage:

                              • OS(C:) : WD_BLACK SN770 1TB PCIe 4.0 NVMe M.2 SSD
                              • DATA (D:) : Western Digital WDC WD10EZEX-22MFCA0 1000.2 GB 7200RPM SATA HDD
                              • WORKSPACE (E:) : Seagate ST1000DM003-1ER162 1000.2 GB 7200RPM SATA HDD
                          
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/* Restore images, videos, iframes, canvas */
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filter: invert(1) hue-rotate(180deg) !important;
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Inconsistent and counterintuitive codegen behavior of `+` operator for `Vector512<T>` depending on the number and order of operands generated by compare instructions, unlike for `Vector256<T>` · Issue #92261 · dotnet/runtime · GitHub
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                              Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T> #92261
                              Closed
                              #92282
                              Closed
                              Inconsistent and counterintuitive codegen behavior of + operator for Vector512<T> depending on the number and order of operands generated by compare instructions, unlike for Vector256<T>#92261
                              #92282
                              Labels
                              area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMIavx512Related to the AVX-512 architecture
                              Description
                              @MineCake147E
                              MineCake147E
                              opened on Sep 19, 2023
                              Description
                              When I was playing with the Vector512<T>, I found some inconsistent behavior of + operator for Vector512<byte>, depending on one or more arguments being generated by Vector512.Equals or not.
                              Both the .NET 7 and .NET 8 RC 1 are doing the right thing for Vector256<byte>:
                              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));
                              In .NET 7, it generates:
                              vzerouppermovrax,qword ptr [rsp+28h]vmovupdymm0,ymmword ptr [rdx]vmovupdymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovupd ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret
                              In .NET 8 RC 1, it generates:
                              vzerouppermovrax,qword ptr [rsp+28h]vmovupsymm0,ymmword ptr [rdx]vmovupsymm1,ymmword ptr [r9]vpcmpeqb ymm2,ymm0,ymmword ptr [r8]vpcmpeqb ymm3,ymm1,ymmword ptr [rax]vpaddbymm2,ymm2,ymm3vpblendvbymm0,ymm0,ymm1,ymm2vmovups ymmword ptr [rcx],ymm0movrax,rcxvzeroupperret
                              But when it comes to Vector512<byte>, it somehow goes wrong.
                              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                              In .NET 8 RC 1, it generates:
                              vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 ; WRONG INSTRUCTION!vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                              While what I expect it to generate looks like:
                              vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                              And even weirder, if I add Vector512<byte>.Zero in advance of adding second operand, like:
                              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                              It generates what I expect it to generate from Test512Blend:
                              vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                              Adding the Vector512<T>.Zero MUST NOT alter the result of the whole integer + operation.
                              Reproduction Steps
                              1. Obtain a JIT assembly for the codes below with .NET 8 RC 1:
                              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector256<byte>Test1(Vector256<byte>ymm0,Vector256<byte>ymm1,Vector256<byte>ymm2,Vector256<byte>ymm3)=>Avx2.BlendVariable(ymm0,ymm2,Vector256.Equals(ymm0,ymm1)+Vector256.Equals(ymm2,ymm3));
                              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                              Expected behavior
                              The code:
                              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                              and
                              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                              For both functions, it should generate something like:
                              vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                              Actual behavior
                              For the code:
                              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512.Equals(zmm2,zmm3));
                              It instead generates something like:
                              vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpcmpeqb k2,zmm1,zmmword ptr [rax]kaddq k1,k1,k2 vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                              Regression?
                              Unknown
                              Known Workarounds
                              By adding Vector512<T>.Zero in advance of adding second operand, like:
                              [MethodImpl(MethodImplOptions.AggressiveOptimization)]privatestaticVector512<byte>Test512Blend3(Vector512<byte>zmm0,Vector512<byte>zmm1,Vector512<byte>zmm2,Vector512<byte>zmm3)=>Avx512BW.BlendVariable(zmm0,zmm2,Vector512.Equals(zmm0,zmm1)+Vector512<byte>.Zero+Vector512.Equals(zmm2,zmm3));
                              It generates:
                              vzerouppermovrax,qword ptr [rsp+28h]vmovupszmm0,zmmword ptr [rdx]vmovupszmm1,zmmword ptr [r9]vpcmpeqb k1,zmm0,zmmword ptr [r8]vpmovm2bzmm2,k1 vpcmpeqb k1,zmm1,zmmword ptr [rax]vpmovm2bzmm3,k1 vpaddbzmm2,zmm2,zmm3vpmovb2m k1,zmm2vpblendmbzmm0{k1},zmm0,zmm1vmovups zmmword ptr [rcx],zmm0movrax,rcxvzeroupperret
                              Configuration
                              • .NET version: 8.0.100-rc.1.23455.8
                              • PC: Custom built PC

                                • OS: Windows 11 Home 22H2 (22621.2283)
                                • CPU: Intel(R) Xeon(R) w5-2455X 3.19 GHz
                                • RAM: 32 GB DDR5 ECC RDIMM
                                • Graphics: NVIDIA GeForce GTX1060(6 GB)
                                • Storage:

                                  • OS(C:) : WD_BLACK SN770 1TB PCIe 4.0 NVMe M.2 SSD
                                  • DATA (D:) : Western Digital WDC WD10EZEX-22MFCA0 1000.2 GB 7200RPM SATA HDD
                                  • WORKSPACE (E:) : Seagate ST1000DM003-1ER162 1000.2 GB 7200RPM SATA HDD
                              
Visual Studio 2022 installation

                              Microsoft Visual Studio Community 2022
                              
Version 17.8.0 Preview 2.0
                              
VisualStudio.17.Preview/17.8.0-pre.2.0+34112.27
                              
Microsoft .NET Framework
                              
Version 4.8.09032
                              インストールされているバージョン:Community
                              Visual C++ 2022 00482-90000-00000-AA248
                              
Microsoft Visual C++ 2022
                              ASP.NET and Web Tools 17.8.226.21692
                              
ASP.NET and Web Tools
                              AvaloniaPackage Extension 1.0
                              
AvaloniaPackage Visual Studio Extension Detailed Info
                              Azure App Service Tools v3.0.0 17.8.226.21692
                              
Azure App Service Tools v3.0.0
                              Azure Functions and Web Jobs Tools 17.8.226.21692
                              
Azure Functions and Web Jobs Tools
                              C# ツール 4.8.0-2.23429.7+44555193fd1135b5d53a2099f76fec91e0d1ebde
                              
IDE で使用する C# コンポーネント。プロジェクトの種類や設定に応じて、異なるバージョンのコンパイラを使用できます。
                              Code Cleanup On Save 1.0.12
                              
Automatically run one of the Code Clean profiles when saving the document. This ensures your code is always formatted correctly and follows your coding style conventions.
                              Common Azure Tools 1.10
                              
Provides common services for use by Azure Mobile Services and Microsoft Azure Tools.
                              Extensibility Message Bus 1.4.39 (main@e8108eb)
                              
Provides common messaging-based MEF services for loosely coupled Visual Studio extension components communication and integration.
                              File Icons 2.7
                              
Adds icons for files that are not recognized by Solution Explorer
                              Microsoft JVM Debugger 1.0
                              
Provides support for connecting the Visual Studio debugger to JDWP compatible Java Virtual Machines
                              Mono Debugging for Visual Studio 17.8.14 (0c9914e)
                              
Support for debugging Mono processes with Visual Studio.
                              NuGet パッケージ マネージャー 6.8.0
                              
Visual Studio 内の NuGet パッケージ マネージャー。NuGet の詳細については、https://docs.nuget.org/ にアクセスしてください
                              Razor (ASP.NET Core) 17.8.2.2345506+ade90399d42c1a7bf92191b1c067816c0ae1c311
                              
ASP.NET Core Razor の言語サービスを提供します。
                              SonarLint for Visual Studio 7.3.0.77872
                              
SonarLint is an extension to your favorite IDE that provides on-the-fly feedback to developers on new bugs and quality issues injected into their code.
                              SQL Server Data Tools 17.8.64.0
                              
Microsoft SQL Server Data Tools
                              Tweaks 2022 1.1.143
                              
A collection of minor fixes and tweaks for Visual Studio to reduce the paper cuts and make you a happier developer
                              TypeScript Tools 17.0.20830.2001
                              
TypeScript Tools for Microsoft Visual Studio
                              Visual Basic ツール 4.8.0-2.23429.7+44555193fd1135b5d53a2099f76fec91e0d1ebde
                              
IDE で使用する Visual Basic コンポーネント。プロジェクトの種類や設定に応じて、異なるバージョンのコンパイラを使用できます。
                              Visual F# Tools 17.8.0-beta.23425.10+0d3549fa5b8b6387ade191d76768405cefed8229
                              
Microsoft Visual F# Tools
                              Visual Studio IntelliCode 2.2
                              
Visual Studio 向けの AI 支援付き開発。
                              VisualStudio.DeviceLog 1.0
                              
パッケージに関する情報
                              VisualStudio.Mac 1.0
                              
Mac Extension for Visual Studio
                              Xamarin 17.8.0.118 (main@35c256f)
                              
Xamarin.iOS と Xamarin.Android の開発を有効にする Visual Studio 拡張機能
                              Xamarin Designer 17.8.1.11 (remotes/origin/d17-8@13ef934098)
                              
Visual Studio で Xamarin Designer ツールを有効にするための Visual Studio 拡張機能。
                              Xamarin Templates 17.8.16 (830b56a)
                              
Templates for building iOS, Android, and Windows apps with Xamarin and Xamarin.Forms.
                              Xamarin.Android SDK 13.2.1.2 (d17-5/a8a26c7)
                              
Xamarin.Android Reference Assemblies and MSBuild support.
                              
Mono: d9a6e87
                              
Java.Interop: xamarin/java.interop/d17-5@149d70fe
                              
SQLite: xamarin/sqlite@68c69d8
                              
Xamarin.Android Tools: xamarin/xamarin-android-tools/d17-5@ca1552d
                              Xamarin.iOS and Xamarin.Mac SDK 16.4.0.16 (b5972410d)
                              
Xamarin.iOS and Xamarin.Mac Reference Assemblies and MSBuild support.
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                                area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMIavx512Related to the AVX-512 architecture
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