Merge branch 'cmp0x38v2' into 'master'

Draft: ntoskrnl: implement cmp instruction with opcodes 0x38,0x39

See merge request wine/wine!714
This commit is contained in:
Etaash Mathamsetty 2024-11-18 08:23:59 +00:00
commit c6085a36d6

View file

@ -889,7 +889,50 @@ static DWORD emulate_instruction( EXCEPTION_RECORD *rec, CONTEXT *context )
} }
break; /* Unable to emulate it */ break; /* Unable to emulate it */
} }
case 0x38:
case 0x39: /* cmp r/m r/m */
{
ULONG64 *data = (ULONG64*)INSTR_GetOperandAddr(context, instr + 1, prefixlen + 1, long_addr, rex, segprefix, &len);
ULONG64 *data2 = (ULONG64*)INSTR_GetOperandAddr(context, instr + 2, prefixlen + 2, long_addr, rex, segprefix, &len);
SIZE_T offset = (BYTE*)data - user_shared_data;
SIZE_T offset2 = (BYTE*)data2 - user_shared_data;
SIZE_T data_size = get_op_size(long_op, rex);
BOOL is_user_shared_data = FALSE;
ULONG64 cmp1, cmp2, bitmask;
if(offset <= KSHARED_USER_DATA_PAGE_SIZE - data_size)
{
TRACE("USD offset %#x at %p\n",(unsigned int) offset, (void*) context->Rip);
data = (ULONG64*)(wine_user_shared_data + offset);
is_user_shared_data = TRUE;
}
if(offset2 <= KSHARED_USER_DATA_PAGE_SIZE - data_size)
{
TRACE("USD offset %#x at %p\n", (unsigned int) offset2, (void*) context->Rip);
data2 = (ULONG64*)(wine_user_shared_data + offset2);
is_user_shared_data = TRUE;
}
if(is_user_shared_data)
{
/* clear ZF and CF */
context->EFlags &= ~(1UL << 6);
context->EFlags &= ~(1UL);
bitmask = ((1ULL << (8 * data_size)) - 1);
/* FIXME("bitmask %llx\n", bitmask); */
cmp1 = (*data) & bitmask;
cmp2 = (*data2) & bitmask;
if(cmp1 == cmp2)
context->EFlags |= (1UL << 6); /* ZF */
else if(cmp1 < cmp2)
context->EFlags |= 1UL; /* CF */
context->Rip += prefixlen + len + 1;
return ExceptionContinueExecution;
}
break;
}
case 0xa0: /* mov Ob, AL */ case 0xa0: /* mov Ob, AL */
case 0xa1: /* mov Ovqp, rAX */ case 0xa1: /* mov Ovqp, rAX */
{ {