[FAST486]

[reactos.git] / lib / fast486 / extraops.c

diff --git a/lib/fast486/extraops.c b/lib/fast486/extraops.c
index 8ac7fc2..7c6da5e 100644 (file)
--- a/lib/fast486/extraops.c
+++ b/lib/fast486/extraops.c
@@ -45,7 +45,7 @@ Fast486ExtendedHandlers[FAST486_NUM_OPCODE_HANDLERS] =
     NULL, // TODO: OPCODE 0x03 NOT IMPLEMENTED
     NULL, // TODO: OPCODE 0x04 NOT IMPLEMENTED
     NULL, // TODO: OPCODE 0x05 NOT IMPLEMENTED
     NULL, // TODO: OPCODE 0x03 NOT IMPLEMENTED
     NULL, // TODO: OPCODE 0x04 NOT IMPLEMENTED
     NULL, // TODO: OPCODE 0x05 NOT IMPLEMENTED

-    NULL, // TODO: OPCODE 0x06 NOT IMPLEMENTED
+    Fast486ExtOpcodeClts,

     NULL, // TODO: OPCODE 0x07 NOT IMPLEMENTED
     NULL, // TODO: OPCODE 0x08 NOT IMPLEMENTED
     NULL, // TODO: OPCODE 0x09 NOT IMPLEMENTED
     NULL, // TODO: OPCODE 0x07 NOT IMPLEMENTED
     NULL, // TODO: OPCODE 0x08 NOT IMPLEMENTED
     NULL, // TODO: OPCODE 0x09 NOT IMPLEMENTED


@@ -299,6 +299,23 @@ Fast486ExtendedHandlers[FAST486_NUM_OPCODE_HANDLERS] =
 
 /* PUBLIC FUNCTIONS ***********************************************************/
 
 
 /* PUBLIC FUNCTIONS ***********************************************************/
 

+FAST486_OPCODE_HANDLER(Fast486ExtOpcodeClts)
+{
+    NO_LOCK_PREFIX();
+
+    /* The current privilege level must be zero */
+    if (Fast486GetCurrentPrivLevel(State) != 0)
+    {
+        Fast486Exception(State, FAST486_EXCEPTION_GP);
+        return FALSE;
+    }
+
+    /* Clear the task switch bit */
+    State->ControlRegisters[FAST486_REG_CR0] &= ~FAST486_CR0_TS;
+
+    return TRUE;
+}
+

 FAST486_OPCODE_HANDLER(Fast486ExtOpcodeStoreControlReg)
 {
     BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
 FAST486_OPCODE_HANDLER(Fast486ExtOpcodeStoreControlReg)
 {
     BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;