What registers need preserved in Microsoft x86-64 Calling convention?

Question

I cant seem to find what registers need to be preserved in the x86-64 Microsoft calling convention. I understand the first 4 parameters are in rcx/rdx/r8/r9 (Assuming non-floats). But what other registers do I need to preserve/if any?

For example in CDECL I have to preserve EBX/EDI/ESI. Is there any such notion in x86-64, or can I simply use any of the available registers?

x86-64 Microsoft (Windows x64) is a different calling convention than the x86-64 System V ABI: Why does Windows64 use a different calling convention from all other OSes on x86-64?

Thanks Harold! I cant mark it as the answer since it was posted a comment.. — Without Me It Just Aweso, Jan 02 '14 at 19:15

score 0 · Accepted Answer · edited Apr 11 '22 at 13:26

0

This answer was provided by harold as a comment, but moving it here so I can mark it as the answer:

x64 Calling Conventions - Register Usage

edited Apr 11 '22 at 13:26

phuclv

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answered Jan 03 '14 at 12:26

Without Me It Just Aweso

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What registers need preserved in Microsoft x86-64 Calling convention?

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