Inquiry on AArch64 Simulator in GDB

Dear GDB Mailing List,

I hope this message finds you well. I am reaching out to express my keen
interest in the AArch64 simulator included within GDB.  (the one in
[binutils-gdb.git]/sim/aarch64/)

Despite my efforts, I have encountered difficulty in locating detailed
documentation or introductions that shed light on several aspects of this
simulator.

My inquiries primarily revolve around its capabilities and limitations with
regard to the ARM64 instruction set.

Specifically, I am eager to understand:

1. Which ARM64 instructions are supported by the AArch64 simulator?
2. Which version of the ARM standard does it adhere to? like v8 v8.1...?
3. Are there any extensions to the instruction set that the simulator
supports? like pauth, crypto, neon, etc
3. Could you provide details on any instructions that are explicitly not
supported?
4. Is the simulator limited to user-mode instructions, or does it offer
broader functionality?
5. Lastly, I would appreciate insights into any known issues, limitations,
or scenarios where the AArch64 simulator may not be suitable for use.

I believe understanding these aspects will greatly enhance my ability to
utilize the AArch64 simulator effectively within GDB for development and
testing purposes. Your guidance and any available documentation or
resources on this topic would be immensely valuable.

Thank you for your time and assistance. I look forward to your response and
any information you can share.

Best regards