README

SHA2 for Pascal

SHA2 algorithm implemented by Pascal.

It contains SHA224, SHA256, SHA384, SHA512, SHA512/224, SHA512/256.

You can find SHA2 standard here.

Highlights

• For Free Pascal 3.2.2, it does not have SHA2 unit, so you can use this to add it.
• For Free Pascal 3.3.1, the fpsha256 and fpsha512 in fcl-hash is not optimized.
• For Delphi, the code's performance in System.Hash is not optimized.
• The SHA256 part have specialized optimization assembler code for i386 and x86_64(basic instruction set).
• The SHA512 part have specialized optimization assembler code for x86_64(basic instruction set).

Benchmark

1 GiB buffer, use FPC 3.2.2 and FPC 3.3.1, optimization level 2, assembler code and pure pascal code.

CPU: AMD Ryzen 5 4600H, System: Windows 11 22H2

FPC 3.2.2	i386	x86_64
SHA256 Asm	266 MiB/s	281 MiB/s
SHA256 Pas	173 MiB/s	230 MiB/s
SHA512 Asm	N/A	465 MiB/s
SHA512 Pas	65 MiB/s	360 MiB/s

FPC 3.3.1	i386	x86_64
SHA256 Asm	276 MiB/s	299 MiB/s
SHA256 Pas	145 MiB/s	228 MiB/s
SHA512 Asm	N/A	468 MiB/s
SHA512 Pas	63 MiB/s	365 MiB/s

FPC 3.3.1 seems have better optimization, but the i386 pure pascal is regressed (SHA256 Pas, 173 MiB/s vs 145 MiB/s).

How to use

Copy files in source directory to the place you like or add it to search path.

You can find some demos in demos directory.

TODO

Use SSE2 for i386 and x86_64.