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implement asm coroutine

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This commit is contained in:
Christoph Urlacher
2022-05-23 09:11:59 +02:00
parent d3b9b937fb
commit 4f94ccdc99
1 changed files with 64 additions and 4 deletions
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68
c_os/kernel/corouts/Coroutine.asm
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@ -27,25 +27,85 @@
;
; C Prototyp: void Coroutine_start (struct CoroutineState* regs);
;; Coroutine_start is called with one arg: CoroutineState* regs, so the main stack looks like this:
;; == High address ==
;; *REGS
;; SP: RET ADDR
;; == Low address ==
Coroutine_start:
; *
; * Hier muss Code eingefuegt werden
; *
;; Set eax to the address where the CoroutineState struct is in memory:
mov eax, [esp + 0x4]
;; Now eax points to the beginning of CoroutineState:
;; struct CoroutineState {
;; == Low address ==
;; EAX: void *ebx;
;; void *esi;
;; void *edi;
;; void *ebp;
;; void *esp;
;; == High address ==
;; };
;; Load the contents of CoroutineState to the registers
mov esp, [eax + esp_offset]
;; The stackpointer now points to the coroutine stack
;; struct CoroutineState {
;; == High address ==
;; *OBJECT
;; 0x13115
;; SP: *KICKOFF
;; == Low address ==
;; };
;; Return to kickoff
ret
; COROUTINE_SWITCH : Coroutinenumschaltung. Der aktuelle Registersatz wird
; gesichert und der Registersatz der neuen Coroutine
; wird in den Prozessor eingelesen.
;
; C Prototyp: void Coroutine_switch (struct CoroutineState* regs_now,
; struct CoroutineState* reg_then);
; C Prototyp: void Coroutine_switch (struct CoroutineState* regs_now, struct CoroutineState* reg_then);
;
; Achtung: Die Parameter werden von rechts nach links uebergeben.
;
;; == High address ==
;; *REGS_THEN
;; *REGS_NOW
;; SP --> RET ADDR
;; == Low address ==
Coroutine_switch:
; *
; * Hier muss Code eingefuegt werden
; *
;; Make eax point to beginning of regs_now in memory
mov eax, [esp + 0x4]
;; Save current coroutine registers
mov [eax + ebx_offset], ebx
mov [eax + esi_offset], esi
mov [eax + edi_offset], edi
mov [eax + ebp_offset], ebp
mov [eax + esp_offset], esp
;; Make eax point to beginning of regs_then in memory
mov eax, [esp + 0x8]
;; Load next coroutine registers
mov ebx, [eax + ebx_offset]
mov esi, [eax + esi_offset]
mov edi, [eax + edi_offset]
mov ebp, [eax + ebp_offset]
mov esp, [eax + esp_offset]
;; Stackpointer now points to kickoff address, ret jumps there
;; NOTE: The stackpointer only points to kickoff if the next coroutine was just initialized.
;; Otherwise it just points somewhere in the next coroutines stack
ret