mirror of
https://github.com/UberGames/ioef.git
synced 2024-11-24 05:01:40 +00:00
* More robust x86 vm entrypoint/callback assembly (Tron)
This commit is contained in:
Tim Angus
parent
d781a25157
commit
1af6eb9592
1 changed files with 74 additions and 96 deletions
|
|
@ -53,7 +53,6 @@ static void VM_Destroy_Compiled(vm_t* self);
|
|||
|
||||
*/
|
||||
|
||||
// TTimo: initialised the statics, this fixes a crash when entering a compiled VM
|
||||
static byte *buf = NULL;
|
||||
static byte *jused = NULL;
|
||||
static int compiledOfs = 0;
|
||||
|
|
@ -71,9 +70,6 @@ int _ftol( float );
|
|||
static int ftolPtr = (int)_ftol;
|
||||
#endif
|
||||
|
||||
void AsmCall( void );
|
||||
static int asmCallPtr = (int)AsmCall;
|
||||
|
||||
#else // _MSC_VER
|
||||
|
||||
#if defined( FTOL_PTR )
|
||||
|
|
@ -88,10 +84,11 @@ int qftol0F7F( void );
|
|||
static int ftolPtr = (int)qftol0F7F;
|
||||
#endif // FTOL_PTR
|
||||
|
||||
void doAsmCall( void );
|
||||
static int asmCallPtr = (int)doAsmCall;
|
||||
#endif
|
||||
|
||||
void AsmCall(void);
|
||||
static void (*const asmCallPtr)(void) = AsmCall;
|
||||
|
||||
|
||||
static int callMask = 0;
|
||||
|
||||
|
|
@ -124,7 +121,7 @@ vm_t* savedVM;
|
|||
__asm {
|
||||
mov eax, dword ptr [edi]
|
||||
sub edi, 4
|
||||
or eax,eax
|
||||
test eax,eax
|
||||
jl systemCall
|
||||
// calling another vm function
|
||||
shl eax,2
|
||||
|
|
@ -137,8 +134,7 @@ systemCall:
|
|||
|
||||
// convert negative num to system call number
|
||||
// and store right before the first arg
|
||||
neg eax
|
||||
dec eax
|
||||
not eax
|
||||
|
||||
push ebp
|
||||
mov ebp, esp
|
||||
|
|
@ -180,68 +176,58 @@ _asm {
|
|||
#else //!_MSC_VER
|
||||
|
||||
#if defined(__MINGW32__) || defined(MACOS_X) // _ is prepended to compiled symbols
|
||||
#define CMANG(sym) "_"#sym
|
||||
# define CMANG(sym) "_"#sym
|
||||
#else
|
||||
#define CMANG(sym) #sym
|
||||
# define CMANG(sym) #sym
|
||||
#endif
|
||||
|
||||
static int callProgramStack;
|
||||
static int *callOpStack;
|
||||
static int callSyscallNum;
|
||||
|
||||
void callAsmCall(void)
|
||||
static void __attribute__((cdecl, used)) CallAsmCall(int const syscallNum,
|
||||
int const programStack, int* const opStack)
|
||||
{
|
||||
vm_t *savedVM;
|
||||
int *callOpStack2;
|
||||
|
||||
savedVM = currentVM;
|
||||
callOpStack2 = callOpStack;
|
||||
vm_t *const vm = currentVM;
|
||||
intptr_t *const data = (intptr_t*)(vm->dataBase + programStack + 4);
|
||||
|
||||
// save the stack to allow recursive VM entry
|
||||
currentVM->programStack = callProgramStack - 4;
|
||||
*(int *)((byte *)currentVM->dataBase + callProgramStack + 4) = callSyscallNum;
|
||||
//VM_LogSyscalls((int *)((byte *)currentVM->dataBase + callProgramStack + 4) );
|
||||
*(callOpStack2+1) = currentVM->systemCall( (intptr_t *)((byte *)currentVM->dataBase + callProgramStack + 4) );
|
||||
vm->programStack = programStack - 4;
|
||||
*data = syscallNum;
|
||||
opStack[1] = vm->systemCall(data);
|
||||
|
||||
currentVM = savedVM;
|
||||
currentVM = vm;
|
||||
}
|
||||
|
||||
// Note the C space function AsmCall is never actually called, and is in fact
|
||||
// arbitrarily named (though this is not true for the MSC version). When a vm
|
||||
// makes a system call, control jumps straight to the doAsmCall label.
|
||||
void AsmCall( void ) {
|
||||
__asm__( CMANG(doAsmCall) ": \n\t" \
|
||||
" movl (%%edi),%%eax \n\t" \
|
||||
" subl $4,%%edi \n\t" \
|
||||
" orl %%eax,%%eax \n\t" \
|
||||
" jl systemCall \n\t" \
|
||||
" shll $2,%%eax \n\t" \
|
||||
" addl %3,%%eax \n\t" \
|
||||
" call *(%%eax) \n\t" \
|
||||
" movl (%%edi),%%eax \n\t" \
|
||||
" andl " CMANG(callMask) ", %%eax \n\t" \
|
||||
" jmp doret \n\t" \
|
||||
"systemCall: \n\t" \
|
||||
" negl %%eax \n\t" \
|
||||
" decl %%eax \n\t" \
|
||||
" movl %%eax,%0 \n\t" \
|
||||
" movl %%esi,%1 \n\t" \
|
||||
" movl %%edi,%2 \n\t" \
|
||||
" pushl %%ecx \n\t" \
|
||||
" pushl %%esi \n\t" \
|
||||
" pushl %%edi \n\t" \
|
||||
" call " CMANG(callAsmCall) " \n\t" \
|
||||
" popl %%edi \n\t" \
|
||||
" popl %%esi \n\t" \
|
||||
" popl %%ecx \n\t" \
|
||||
" addl $4,%%edi \n\t" \
|
||||
"doret: \n\t" \
|
||||
" ret \n\t" \
|
||||
: "=rm" (callSyscallNum), "=rm" (callProgramStack), "=rm" (callOpStack) \
|
||||
: "m" (instructionPointers) \
|
||||
: "ax", "di", "si", "cx" \
|
||||
);
|
||||
}
|
||||
__asm__(
|
||||
".text\n\t"
|
||||
".p2align 4,,15\n\t"
|
||||
#if defined __ELF__
|
||||
".type " CMANG(AsmCall) ", @function\n"
|
||||
#endif
|
||||
CMANG(AsmCall) ":\n\t"
|
||||
"movl (%edi), %eax\n\t"
|
||||
"subl $4, %edi\n\t"
|
||||
"testl %eax, %eax\n\t"
|
||||
"jl 0f\n\t"
|
||||
"shll $2, %eax\n\t"
|
||||
"addl " CMANG(instructionPointers) ", %eax\n\t"
|
||||
"call *(%eax)\n\t"
|
||||
"movl (%edi), %eax\n\t"
|
||||
"andl " CMANG(callMask) ", %eax\n\t"
|
||||
"ret\n"
|
||||
"0:\n\t" // system call
|
||||
"notl %eax\n\t"
|
||||
"pushl %ecx\n\t"
|
||||
"pushl %edi\n\t" // opStack
|
||||
"pushl %esi\n\t" // programStack
|
||||
"pushl %eax\n\t" // syscallNum
|
||||
"call " CMANG(CallAsmCall) "\n\t"
|
||||
"addl $12, %esp\n\t"
|
||||
"popl %ecx\n\t"
|
||||
"addl $4, %edi\n\t"
|
||||
"ret\n\t"
|
||||
#if defined __ELF__
|
||||
".size " CMANG(AsmCall)", .-" CMANG(AsmCall)
|
||||
#endif
|
||||
);
|
||||
|
||||
#endif
|
||||
|
||||
static int Constant4( void ) {
|
||||
|
|
@ -1142,7 +1128,6 @@ int VM_CallCompiled( vm_t *vm, int *args ) {
|
|||
int programStack;
|
||||
int stackOnEntry;
|
||||
byte *image;
|
||||
void *entryPoint;
|
||||
void *opStack;
|
||||
int *oldInstructionPointers;
|
||||
|
||||
|
|
@ -1181,45 +1166,38 @@ int VM_CallCompiled( vm_t *vm, int *args ) {
|
|||
*(int *)&image[ programStack ] = -1; // will terminate the loop on return
|
||||
|
||||
// off we go into generated code...
|
||||
entryPoint = vm->codeBase;
|
||||
opStack = &stack;
|
||||
|
||||
#ifdef _MSC_VER
|
||||
__asm {
|
||||
pushad
|
||||
mov esi, programStack;
|
||||
mov edi, opStack
|
||||
call entryPoint
|
||||
mov programStack, esi
|
||||
mov opStack, edi
|
||||
popad
|
||||
}
|
||||
#else
|
||||
{
|
||||
static int memProgramStack;
|
||||
static void *memOpStack;
|
||||
static void *memEntryPoint;
|
||||
#ifdef _MSC_VER
|
||||
void *entryPoint = vm->codeBase;
|
||||
|
||||
memProgramStack = programStack;
|
||||
memOpStack = opStack;
|
||||
memEntryPoint = entryPoint;
|
||||
__asm {
|
||||
pushad
|
||||
mov esi, programStack
|
||||
mov edi, opStack
|
||||
call entryPoint
|
||||
mov programStack, esi
|
||||
mov opStack, edi
|
||||
popad
|
||||
}
|
||||
#else
|
||||
/* These registers are used as scratch registers and are destroyed after the
|
||||
* call. Do not use clobber, so they can be used as input for the asm. */
|
||||
unsigned eax;
|
||||
unsigned ebx;
|
||||
unsigned ecx;
|
||||
unsigned edx;
|
||||
|
||||
__asm__(" pushal \n" \
|
||||
" movl %0,%%esi \n" \
|
||||
" movl %1,%%edi \n" \
|
||||
" call *%2 \n" \
|
||||
" movl %%esi,%0 \n" \
|
||||
" movl %%edi,%1 \n" \
|
||||
" popal \n" \
|
||||
: "=m" (memProgramStack), "=m" (memOpStack) \
|
||||
: "m" (memEntryPoint), "m" (memProgramStack), "m" (memOpStack) \
|
||||
: "si", "di" \
|
||||
__asm__ volatile(
|
||||
"call *%6"
|
||||
: "+S" (programStack), "+D" (opStack),
|
||||
"=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx)
|
||||
: "mr" (vm->codeBase)
|
||||
: "cc", "memory"
|
||||
);
|
||||
|
||||
programStack = memProgramStack;
|
||||
opStack = memOpStack;
|
||||
}
|
||||
#endif
|
||||
}
|
||||
|
||||
if ( opStack != &stack[1] ) {
|
||||
Com_Error( ERR_DROP, "opStack corrupted in compiled code" );
|
||||
|
|
|
|||
Loading…
Reference in a new issue