2023-11-30 09:44:31 +00:00
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+++
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title = "x86_64 Assembly notes"
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date = 2023-11-30
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draft = true
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description = "Notes I gathered for myself as I learn."
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[taxonomies]
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categories = ["asm", "nasm", "x86_64"]
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+++
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Here is a post I will probably update as I learn more x86_64 assembly.
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2023-11-30 10:13:11 +00:00
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# AMD64 ABI Reference
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From left to right, pass as many parameters as will fit in registers. The order in which registers are allocated, are:
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- For non-floats: rdi, rsi, rdx, rcx, r8, r9.
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- For floating-point: xmm0, xmm1, xmm2, xmm3, xmm4, xmm5, xmm6, xmm7.
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- Callee saved: rsp, rbx, rbp, r12-r15
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- Return value: `rax`
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- Stack pointer: `rsp`
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- Base pointer: `rbp`
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# Call Frame
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Stack grows downwards.
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```asm
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caller:
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push rbp ; save old frame
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mov rbp, rsp ; init frame
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; arguments passed in the stack are upwards
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mov r14, [rbp + 0x10]
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; ...
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mov rsp, rbp
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pop rbp
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ret
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```
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2023-11-30 09:44:31 +00:00
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## x86_64 Cheatsheet
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|s|b|
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|---|---|
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|a|b|
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2023-11-30 10:13:11 +00:00
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|a|b|
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|a|b|
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|a|b|
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