ARM64

This is just a quick reference sheet for developers.

ARM64 is not currently implemented.

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Registers

Register	ARM64 (System V)	Volatile/Non-Volatile
x0-x7	Parameter/Result Registers	Volatile
x8	Indirect result location register	Volatile
x9-x15	Local Variables	Volatile
x16-x17	Intra-procedure-call scratch registers	Volatile
x18	Platform register, conventionally the TLS base	Volatile
x19-x28	Registers saved across function calls	Non-Volatile
x29	Frame pointer	Non-Volatile
x30	Link register	Volatile
sp	Stack pointer	Non-Volatile
xzr	Zero register, always reads as zero	N/A
x31	Stack pointer or zero register, contextually reads as either sp or xzr	N/A

For floating point / SIMD registers:

Register	ARM64 (System V)	Volatile/Non-Volatile
v0-v7	Parameter/Result registers	Volatile
v8-v15	Temporary registers	Volatile
v16-v31	Registers saved across function calls	Non-Volatile

Calling Convention Inference

It is recommended library users manually specify conventions in their hook functions."

When the calling convention of <your function> is not specified, wrapper libraries must insert the appropriate default convention in their wrappers.

Rust

• aarch64-unknown-linux-gnu: SystemV
• aarch64-pc-windows-msvc: Windows ARM64

C

• Linux ARM64: SystemV
• Windows ARM64: Windows ARM64