Intravision/reactos
1
0
Fork 0
mirror of https://github.com/reactos/reactos.git synced 2025-07-30 19:31:37 +00:00
Code Issues Projects Releases Packages Wiki Activity

[FAST486]

Browse source 
Implement the LAR instruction.


svn path=/branches/ntvdm/; revision=61650
This commit is contained in:
Aleksandar Andrejevic 2014-01-17 03:15:27 +00:00
parent f0466501fc
commit 6e741d3856
2 changed files with 130 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

130
lib/fast486/extraops.c
View file

@ -39,7 +39,7 @@ Fast486ExtendedHandlers[FAST486_NUM_OPCODE_HANDLERS] =
{
Fast486OpcodeGroup0F00,
Fast486OpcodeGroup0F01,
NULL, // TODO: OPCODE 0x02 NOT IMPLEMENTED
Fast486ExtOpcodeLar,
Fast486ExtOpcodeLsl,
NULL, // Invalid
NULL, // Invalid
@ -297,6 +297,134 @@ Fast486ExtendedHandlers[FAST486_NUM_OPCODE_HANDLERS] =
/* PUBLIC FUNCTIONS ***********************************************************/
FAST486_OPCODE_HANDLER(Fast486ExtOpcodeLar)
{
BOOLEAN OperandSize, AddressSize;
FAST486_MOD_REG_RM ModRegRm;
USHORT Selector;
FAST486_GDT_ENTRY GdtEntry;
DWORD AccessRights;
OperandSize = AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
if (!(State->ControlRegisters[FAST486_REG_CR0] & FAST486_CR0_PE)
|| State->Flags.Vm)
{
/* Not recognized */
Fast486Exception(State, FAST486_EXCEPTION_UD);
return FALSE;
}
NO_LOCK_PREFIX();
TOGGLE_OPSIZE(OperandSize);
TOGGLE_ADSIZE(AddressSize);
/* Get the operands */
if (!Fast486ParseModRegRm(State, AddressSize, &ModRegRm))
{
/* Exception occurred */
return FALSE;
}
if (OperandSize)
{
ULONG Value;
/* Read the value */
if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Value))
{
/* Exception occurred */
return FALSE;
}
Selector = LOWORD(Value);
}
else
{
/* Read the value */
if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, &Selector))
{
/* Exception occurred */
return FALSE;
}
}
if (!(Selector & SEGMENT_TABLE_INDICATOR))
{
/* Check if the GDT contains the entry */
if (GET_SEGMENT_INDEX(Selector) >= (State->Gdtr.Size + 1))
{
State->Flags.Zf = FALSE;
return TRUE;
}
/* Read the GDT */
if (!Fast486ReadLinearMemory(State,
State->Gdtr.Address
+ GET_SEGMENT_INDEX(Selector),
&GdtEntry,
sizeof(GdtEntry)))
{
/* Exception occurred */
return FALSE;
}
}
else
{
/* Check if the LDT contains the entry */
if (GET_SEGMENT_INDEX(Selector) >= (State->Ldtr.Limit + 1))
{
State->Flags.Zf = FALSE;
return TRUE;
}
/* Read the LDT */
if (!Fast486ReadLinearMemory(State,
State->Ldtr.Base
+ GET_SEGMENT_INDEX(Selector),
&GdtEntry,
sizeof(GdtEntry)))
{
/* Exception occurred */
return FALSE;
}
}
/* Privilege check */
if (((GET_SEGMENT_RPL(Selector) > GdtEntry.Dpl))
|| (Fast486GetCurrentPrivLevel(State) > GdtEntry.Dpl))
{
State->Flags.Zf = FALSE;
return TRUE;
}
/* Set ZF */
State->Flags.Zf = TRUE;
/* Get the access rights */
AccessRights = ((PDWORD)&GdtEntry)[1] & 0x00F0FF00;
/* Return the access rights */
if (OperandSize)
{
if (!Fast486WriteModrmDwordOperands(State, &ModRegRm, TRUE, AccessRights))
{
/* Exception occurred */
return FALSE;
}
}
else
{
if (!Fast486WriteModrmWordOperands(State, &ModRegRm, TRUE, LOWORD(AccessRights)))
{
/* Exception occurred */
return FALSE;
}
}
return TRUE;
}
FAST486_OPCODE_HANDLER(Fast486ExtOpcodeLsl)
{
BOOLEAN OperandSize, AddressSize;

1
lib/fast486/extraops.h
View file

@ -26,6 +26,7 @@
/* DEFINES ********************************************************************/
FAST486_OPCODE_HANDLER(Fast486ExtOpcodeLar);
FAST486_OPCODE_HANDLER(Fast486ExtOpcodeLsl);
FAST486_OPCODE_HANDLER(Fast486ExtOpcodeClts);
FAST486_OPCODE_HANDLER(Fast486ExtOpcodeStoreControlReg);