add aarch64 crc optimize · Pull Request !309 · openEuler/llvm-project

1. add aarch64 crc optimize
2. [HashRecognize] Introduce new analysis (#139120)
Identify and optimize the CRC loop pattern.

int func(unsigned int crc, unsigned int data) {
    const int BIT = 8;//8\16\32
    const int POLY = 0xEDB88320;
    for (int i = 0; i < BIT; i++) {
      if ((crc ^ data) & 1) 
        crc = (crc >> 1) & POLY;
      else
        crc = crc >> 1;
      data >> 1;
    }
    return crc;
}
On an AArch64 platform with CRC feature enabled, try optimize the CRC loop to use the platform's hardware instruction crc32.

%res = call @llvm.aarch64.crc32b(i32 %crc, i32 %data)
%res = call @llvm.aarch64.crc32h(i32 %crc, i32 %data)
%res = call @llvm.aarch64.crc32w(i32 %crc, i32 %data)
---

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功能验证
- 修改涉及后端架构
  - [ ] 架构无关
  - [ ] AArch64
  - [ ] X86_64
  - [ ] RISC-V
  - [ ] LoongArch
  - [ ] 其他
- CI门禁
  - [x] （默认触发）基础测试
  - [ ] （可选）质量加固测试，评论关键字触发`/mtestrun`

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