ruby--ruby/coroutine/win32/Context.asm

56 lines
1020 B
NASM

;;
;; This file is part of the "Coroutine" project and released under the MIT License.
;;
;; Created by Samuel Williams on 10/5/2018.
;; Copyright, 2018, by Samuel Williams.
;;
.386
.model flat
.code
assume fs:nothing
; Using fastcall is a big win (and it's the same has how x64 works).
; In coroutine transfer, the arguments are passed in ecx and edx. We don't need
; to touch these in order to pass them to the destination coroutine.
@coroutine_transfer@8 proc
; Save the thread information block:
push fs:[0]
push fs:[4]
push fs:[8]
; Save caller registers:
push ebp
push ebx
push edi
push esi
; Save caller stack pointer:
mov dword ptr [ecx], esp
; Restore callee stack pointer:
mov esp, dword ptr [edx]
; Restore callee stack:
pop esi
pop edi
pop ebx
pop ebp
; Restore the thread information block:
pop fs:[8]
pop fs:[4]
pop fs:[0]
; Save the first argument as the return value:
mov eax, dword ptr ecx
; Jump to the address on the stack:
ret
@coroutine_transfer@8 endp
end