okseby/Quake-III-Arena
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Fixes a crash when compiling the project on windows in 64 bit mode.

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Not all non-volatile registers were actually saved and restored, leading to a few registers being trashed after calling the vm instructions.
All non-volatile registers have been added.
This commit is contained in:
Ch40zz 2021-05-19 18:55:58 +02:00 • committed by Tim Angus
parent 4003a5b78c
commit 60a2000419
1 changed files with 13 additions and 2 deletions
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15
code/asm/vm_x86_64.asm
View file

@ -30,9 +30,15 @@
; uint8_t qvmcall64(int *programStack, int *opStack, intptr_t *instructionPointers, byte *dataBase); ; uint8_t qvmcall64(int *programStack, int *opStack, intptr_t *instructionPointers, byte *dataBase);
qvmcall64 PROC qvmcall64 PROC
push rsi ; push non-volatile registers to stack push r12 ; push all non-volatile registers to stack
push r13
push r14
push r15
push rdi push rdi
push rsi
push rbx push rbx
push rbp
; need to save pointer in rcx so we can write back the programData value to caller ; need to save pointer in rcx so we can write back the programData value to caller
push rcx push rcx
@ -48,9 +54,14 @@ qvmcall64 PROC
mov dword ptr [rcx], esi ; write back the programStack value mov dword ptr [rcx], esi ; write back the programStack value
mov al, bl ; return opStack offset mov al, bl ; return opStack offset
pop rbp ; restore all non-volatile registers after the call
pop rbx pop rbx
pop rdi
pop rsi pop rsi
pop rdi
pop r15
pop r14
pop r13
pop r12
ret ret
qvmcall64 ENDP qvmcall64 ENDP