Port NEON SHA256 intrinsics to pragma-based framework
AArch64 NEON SHA256 intrinsics are now handled by the pragma-based framework, with new assembly tests.
The NEON SHA256 intrinsics, supporting the FEAT_SHA2 feature, have been ported to GCC’s pragma-based framework. This change also introduces assembly tests for each intrinsic to ensure correct functionality. Old builtin functions and definitions have been removed in favor of the new framework.
In Details
This commit refactors the implementation of AArch64 NEON SHA256 intrinsics (FEAT_SHA2) to use the pragma-based framework. Previously, these intrinsics might have been handled differently, potentially leading to less consistent codegen or maintenance overhead. By unifying them under the pragma system, we align with the broader approach for SIMD intrinsics in GCC, improving maintainability and potentially enabling better optimization opportunities through the common framework.
- NEON
- ARM's Advanced SIMD (Single Instruction, Multiple Data) extension, providing hardware acceleration for multimedia and signal processing.
- intrinsics
- Special functions that allow programmers to access hardware instructions directly from high-level code, often providing performance benefits over standard C functions.
- pragma-based framework
- A system within GCC where specific functionalities, particularly for hardware features and built-ins, are managed through a generalized 'pragma' or directive-based approach, allowing for a more unified and maintainable implementation.
- FEAT_SHA2
- A hardware feature on ARM processors that provides acceleration for the SHA-2 cryptographic hash function.