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Move argument passing from VM to engine to global variables which allows to get rid of lots of OS specific stuff and also fixes errors that happens when compilers add lots of boilerplate to the DoSyscall() function

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This commit is contained in:
Thilo Schulz 2012-08-08 09:34:03 +00:00
parent ded2b11959
commit ffac0e6757
2 changed files with 40 additions and 69 deletions
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18
code/asm/vm_x86_64.asm
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@ -23,26 +23,8 @@
;
; assumes __fastcall calling convention
DoSyscall PROTO
.code
; Call to static void DoSyscall(int syscallNum, int programStack, int *opStackBase, uint8_t opStackOfs, intptr_t arg)
qsyscall64 PROC
sub rsp, 28h ; after this esp will be aligned to 16 byte boundary
mov qword ptr [rsp + 20h], rcx ; 5th parameter "arg" is passed on stack
mov r9b, bl ; opStackOfs
mov r8, rdi ; opStackBase
mov edx, esi ; programStack
mov ecx, eax ; syscallNum
mov rax, DoSyscall ; store call address of DoSyscall in rax
call rax
add rsp, 28h
ret
qsyscall64 ENDP
; Call to compiled code after setting up the register environment for the VM
; prototype:
; uint8_t qvmcall64(int *programStack, int *opStack, intptr_t *instructionPointers, byte *dataBase);