AVX512: Fold some bitwise operations to vpternlogq

[EgorBo]

E.g.

bool Test(string s) => s == "https://pkgs.dev.azure.com/dnc";

Currently emits:

; Method Prog:Test(System.String):bool:this
       C5F877               vzeroupper 
       4885D2               test     rdx, rdx
       7431                 je       SHORT G_M52811_IG05
       837A081E             cmp      dword ptr [rdx+08H], 30
       752B                 jne      SHORT G_M52811_IG05
       C5FC10420C           vmovups  ymm0, ymmword ptr[rdx+0CH]
       C5FDEF0535000000     vpxor    ymm0, ymm0, ymmword ptr[reloc @RWD00]
       C5FC104A28           vmovups  ymm1, ymmword ptr[rdx+28H]
       C5F5EF0D48000000     vpxor    ymm1, ymm1, ymmword ptr[reloc @RWD32]
       C5FDEBC1             vpor     ymm0, ymm0, ymm1
       C4E27D17C0           vptest   ymm0, ymm0
       0F94C0               sete     al
       0FB6C0               movzx    rax, al
       EB02                 jmp      SHORT G_M52811_IG06
G_M52811_IG05:              
       33C0                 xor      eax, eax
G_M52811_IG06:              
       C5F877               vzeroupper 
       C3                   ret      
RWD00  	dq	0070007400740068h, 002F002F003A0073h, 00730067006B0070h, 007600650064002Eh
RWD32  	dq	0061002E00760065h, 006500720075007Ah, 006D006F0063002Eh, 0063006E0064002Fh
; Total bytes of code: 63

where for

       C5F5EF0D48000000     vpxor    ymm1, ymm1, ymmword ptr[reloc @RWD32]
       C5FDEBC1             vpor     ymm0, ymm0, ymm1

we could emit:

       C5F5EF0D48000000     vpternlogq      ymm0, ymm1, ymmword ptr [reloc @RWD32], 246

on AVX512 CPU. Same for other bitwise patterns where we can benefit from this.

Reference: https://godbolt.org/z/Tx53eKxf9

llvm-mca diff: https://www.diffchecker.com/UxW51oqr/

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Issue Details

---

E.g.

bool Test(string s) => s == "https://pkgs.dev.azure.com/dnc";

Currently emits:

; Method Prog:Test(System.String):bool:this
       C5F877               vzeroupper 
       4885D2               test     rdx, rdx
       7431                 je       SHORT G_M52811_IG05
       837A081E             cmp      dword ptr [rdx+08H], 30
       752B                 jne      SHORT G_M52811_IG05
       C5FC10420C           vmovups  ymm0, ymmword ptr[rdx+0CH]
       C5FDEF0535000000     vpxor    ymm0, ymm0, ymmword ptr[reloc @RWD00]
       C5FC104A28           vmovups  ymm1, ymmword ptr[rdx+28H]
       C5F5EF0D48000000     vpxor    ymm1, ymm1, ymmword ptr[reloc @RWD32]
       C5FDEBC1             vpor     ymm0, ymm0, ymm1
       C4E27D17C0           vptest   ymm0, ymm0
       0F94C0               sete     al
       0FB6C0               movzx    rax, al
       EB02                 jmp      SHORT G_M52811_IG06
G_M52811_IG05:              ;; offset=0039H
       33C0                 xor      eax, eax
G_M52811_IG06:              ;; offset=003BH
       C5F877               vzeroupper 
       C3                   ret      
RWD00  	dq	0070007400740068h, 002F002F003A0073h, 00730067006B0070h, 007600650064002Eh
RWD32  	dq	0061002E00760065h, 006500720075007Ah, 006D006F0063002Eh, 0063006E0064002Fh
; Total bytes of code: 63

where for

       C5F5EF0D48000000     vpxor    ymm1, ymm1, ymmword ptr[reloc @RWD32]
       C5FDEBC1             vpor     ymm0, ymm0, ymm1

we could emit:

       C5F5EF0D48000000     vpternlogq      ymm0, ymm1, ymmword ptr [reloc @RWD32], 246

on AVX512 CPU.

Reference: https://godbolt.org/z/Tx53eKxf9

Author:	EgorBo
Assignees:	-
Labels:	tenet-performance, area-CodeGen-coreclr
Milestone:	-

[BruceForstall]

@dotnet/avx512-contrib

[DeepakRajendrakumaran]

The entire list of operations can be found in software development manual here - https://www.intel.com/content/www/us/en/developer/articles/technical/intel-sdm.html (Section 5.1)

[Ruihan-Yin]

Hi @EgorBo, @anthonycanino and I will be working on this issue, hope we will have a draft PR shortly.