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Variable passing #1

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IanSeyler opened this issue Sep 30, 2014 · 0 comments

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IanSeyler commented Sep 30, 2014

The kernel uses a non-standard way of passing variables to internal functions. The AMD64 ABI should be investigated to see if it is a good fit.

From the AMD64 ABI:
Passing Once arguments are classified, the registers get assigned (in left-to-right order) for passing as follows:

If the class is MEMORY, pass the argument on the stack.
If the class is INTEGER, the next available register of the sequence %rdi,
%rsi, %rdx, %rcx, %r8 and %r9 is used.
If the class is SSE, the next available vector register is used, the registers
are taken in the order from %xmm0 to %xmm7.

Return values are passed as %rax, %rdx

Linux system call table

IanSeyler changed the title ~~x86-64 variable passing~~ Variable passing

IanSeyler added the x86-64 label

IanSeyler removed the x86-64 label

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