[llvm] [LLVM] add LZMA for compression/decompression (PR #83297)

[Yaxun Liu via llvm-commits]

yxsamliu wrote:

| Compression Method | Level | Original Size (bytes) | Compressed Size (bytes) | Compression Rate | Compression Time (s) | Decompression Time (s) |
|---------------------|-------|-----------------------|-------------------------|------------------|----------------------|------------------------|
| LZMA                | 6     | 68,459,756            | 22,984,456              | ~2.98:1          | 18.7226              | 1.1000                 |
| LZMA                | 9     | 68,459,756            | 4,139,504               | ~16.55:1         | 14.32                | 0.3012                 |
| ZSTD                | 6     | 68,459,756            | 32,612,291              | ~2.10:1          | 0.8067               | 0.0982                 |
| ZSTD                | 9     | 68,459,756            | 31,445,373              | ~2.18:1          | 1.3375               | 0.0933                 |
| ZSTD                | 15    | 68,459,756            | 28,063,493              | ~2.44:1          | 9.7183               | 0.0891                 |
| ZSTD                | 20    | 68,459,756            | 4,394,993               | ~15.59:1         | 2.0157               | 0.0493                 |

It seems we could use zstd level 20 for clang-offload-bundler to achieve similar compression rate as lzma level 9.

https://github.com/llvm/llvm-project/pull/83297