Armv8-A Architecture support in GNU toolchain 

Armv8-A Architecture Feature Architecture Identifier GNU Identifier Enabled by default Binutils GCC
CRC instruction crc ARMv8.1-A or later 2.25 GCC 6
Crypto extension crypto No 2.25 GCC 6
Floating-point extension fp ARMv8-A or later 2.25 GCC 6
Advanced SIMD extension simd ARMv8-A or later 2.25 GCC 6
Limited Ordering Regions extensions ARMv8.1-LOR lor ARMv8.1-A or later 2.26 NA
Privileged Access Never support ARMv8.1-PAN pan ARMv8.1-A or later 2.26 NA
Round Double Multiply Accumulate instructions ARMv8.1-RDMA rdma ARMv8.1-A or later 2.26 GCC 8
FP16 extension ARMv8.2-FP16 fp16 ARMv8.2-A or later 2.26 GCC 7
Statistical Profiling Extensions (SPE) profile No 2.26 GCC 9
Large System Extension (LSE) ARMv8.1-LSE lse ARMv8.1-A or later 2.27 GCC 6
RAS extension ras ARMv8.2-A or later 2.27 NA
Scalable Vector Extension (SVE)
sve No 2.28 GCC 8
Complex number SIMD extension ARMv8.3-CompNum compnum ARMv8.3-A or later 2.28 Planned
Weak release consistency extension ARMv8.3-RCPC rcpc ARMv8.3-A or later 2.29 GCC 8
Pointer Authentication ARMv8.3-PAuth No 2.27 GCC 7
Dot Product extension ARMv8.2-DotProd dotprod ARMv8.4-A or later 2.29 GCC 8
AES cryptographic extension ARMv8.0-AES aes No 2.30 GCC 8
SHA2 cryptographic extension ARMv8.0-SHA sha2 No 2.30 GCC 8
FP16 fmla extension ARMv8.2-FHM fp16fml ARMv8.4-A or later 2.30 GCC 8
SHA512 and SHA3 cryptographic extensions ARMv8.2-SHA sha3 No 2.30 GCC 8
SM3 and SM4 cryptographic extensions ARMv8.2-SM sm4 No 2.30 GCC 8
Memory Tagging Extension (MTE) ARMv8.5-MemTag memtag No 2.32 Planned
Branch Target Indicators (BTI) ARMv8.5-BTI No 2.32 GCC 9
Execution and Data and Prediction instructions ARMv8.0-PredInv predres ARMv8.5-A or later 2.32 GCC 9
Random number instructions ARMv8.5-RNG rng No 2.32 GCC 9
Speculation barrier instruction sb ARMv8.0-SB sb ARMv8.5-A or later 2.32 GCC 9