Xcode arm64 Vs arm64e
arm64 vs arm64e
Both are ABIs (lower level APIs) which compile to instructions (defined by an ISA/ instruction set architecture). arm64e is used on Mac M1's and iPhones. The differences between them are the points in Giovanni's answer.
arm64e vs ARMv8.3?
Both are ambiguously called "architectures". arm64e is not an ISA but an ABI (Application binary interface), and ARMv8.3 is an ARM ISA (technically an extension to AArch64).
In summary, arm64e is an ABI (often called architecture, but not ISA), which compiles to a real ISA. The new Apple devices use arm64e, including M1 macs.
iPhones (e.g. A14, A15), M1 Macs, M1 Pro Macs, etc.
They all use the arm64e ABI, but Apple has an ISA license, and create custom ISAs.
ABI vs Architecture?
The Android documentation has a useful guide about Android ABIs, containing general information:
Different Android devices use different CPUs, which in turn support different instruction sets. Each combination of CPU and instruction set has its own Application Binary Interface (ABI). An ABI includes the following information: read more there
The arm64e architecture is used on the A12 chipset, which is added in the latest 2018 iPhone models (XS/XS Max/XR). The code compiles to ARMv8.3, which brings support for new features. Namely:
- Pointer authentication
- Nested virtualization
- Advanced SIMD complex number support
- Improved Javascript data type conversion support
- A change to the memory consistency model
- ID mechanism support for larger system-visible caches
The A12 features an Apple-designed 64-bit ARMv8.3-A six-core CPU
https://en.wikipedia.org/wiki/Apple_A12
Read more about the architecture here as well:
https://community.arm.com/processors/b/blog/posts/armv8-a-architecture-2016-additions