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[FAST486]
[reactos.git] / lib / fast486 / opcodes.c
diff --git a/lib/fast486/opcodes.c b/lib/fast486/opcodes.c
index 1ef0dec..539b8fe 100644 (file)
--- a/lib/fast486/opcodes.c
+++ b/lib/fast486/opcodes.c
@@ -31,6 +31,7 @@
 #include "opgroups.h"
 #include "extraops.h"
 #include "common.h"
+#include "fpu.h"
 
 /* PUBLIC VARIABLES ***********************************************************/
 
@@ -253,14 +254,14 @@ Fast486OpcodeHandlers[FAST486_NUM_OPCODE_HANDLERS] =
     Fast486OpcodeAad,
     Fast486OpcodeSalc,
     Fast486OpcodeXlat,
-    NULL, // TODO: OPCODE 0xD8 NOT SUPPORTED
-    NULL, // TODO: OPCODE 0xD9 NOT SUPPORTED
-    NULL, // TODO: OPCODE 0xDA NOT SUPPORTED
-    NULL, // TODO: OPCODE 0xDB NOT SUPPORTED
-    NULL, // TODO: OPCODE 0xDC NOT SUPPORTED
-    NULL, // TODO: OPCODE 0xDD NOT SUPPORTED
-    NULL, // TODO: OPCODE 0xDE NOT SUPPORTED
-    NULL, // TODO: OPCODE 0xDF NOT SUPPORTED
+    Fast486FpuOpcodeD8,
+    Fast486FpuOpcodeD9,
+    Fast486FpuOpcodeDA,
+    Fast486FpuOpcodeDB,
+    Fast486FpuOpcodeDC,
+    Fast486FpuOpcodeDD,
+    Fast486FpuOpcodeDE,
+    Fast486FpuOpcodeDF,
     Fast486OpcodeLoop,
     Fast486OpcodeLoop,
     Fast486OpcodeLoop,
@@ -473,19 +474,19 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeIncrement)
     {
         Value = ++State->GeneralRegs[Opcode & 0x07].Long;
 
-        State->Flags.Of = (Value == SIGN_FLAG_LONG) ? TRUE : FALSE;
-        State->Flags.Sf = (Value & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Of = (Value == SIGN_FLAG_LONG);
+        State->Flags.Sf = ((Value & SIGN_FLAG_LONG) != 0);
     }
     else
     {
         Value = ++State->GeneralRegs[Opcode & 0x07].LowWord;
 
-        State->Flags.Of = (Value == SIGN_FLAG_WORD) ? TRUE : FALSE;
-        State->Flags.Sf = (Value & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Of = (Value == SIGN_FLAG_WORD);
+        State->Flags.Sf = ((Value & SIGN_FLAG_WORD) != 0);
     }
 
-    State->Flags.Zf = (Value == 0) ? TRUE : FALSE;
-    State->Flags.Af = ((Value & 0x0F) == 0) ? TRUE : FALSE;
+    State->Flags.Zf = (Value == 0);
+    State->Flags.Af = ((Value & 0x0F) == 0);
     State->Flags.Pf = Fast486CalculateParity(LOBYTE(Value));
 
     /* Return success */
@@ -507,19 +508,19 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeDecrement)
     {
         Value = --State->GeneralRegs[Opcode & 0x07].Long;
 
-        State->Flags.Of = (Value == (SIGN_FLAG_LONG - 1)) ? TRUE : FALSE;
-        State->Flags.Sf = (Value & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Of = (Value == (SIGN_FLAG_LONG - 1));
+        State->Flags.Sf = ((Value & SIGN_FLAG_LONG) != 0);
     }
     else
     {
         Value = --State->GeneralRegs[Opcode & 0x07].LowWord;
 
-        State->Flags.Of = (Value == (SIGN_FLAG_WORD - 1)) ? TRUE : FALSE;
-        State->Flags.Sf = (Value & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Of = (Value == (SIGN_FLAG_WORD - 1));
+        State->Flags.Sf = ((Value & SIGN_FLAG_WORD) != 0);
     }
 
-    State->Flags.Zf = (Value == 0) ? TRUE : FALSE;
-    State->Flags.Af = ((Value & 0x0F) == 0x0F) ? TRUE : FALSE;
+    State->Flags.Zf = (Value == 0);
+    State->Flags.Af = ((Value & 0x0F) == 0x0F);
     State->Flags.Pf = Fast486CalculateParity(LOBYTE(Value));
 
     /* Return success */
@@ -540,7 +541,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodePushReg)
 FAST486_OPCODE_HANDLER(Fast486OpcodePopReg)
 {
     ULONG Value;
-    BOOLEAN Size = State->SegmentRegs[FAST486_REG_SS].Size;
+    BOOLEAN Size = State->SegmentRegs[FAST486_REG_CS].Size;
 
     TOGGLE_OPSIZE(Size);
     NO_LOCK_PREFIX();
@@ -606,10 +607,13 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeShortConditionalJmp)
 {
     BOOLEAN Jump = FALSE;
     CHAR Offset = 0;
+    BOOLEAN Size = State->SegmentRegs[FAST486_REG_CS].Size;
 
     /* Make sure this is the right instruction */
     ASSERT((Opcode & 0xF0) == 0x70);
 
+    TOGGLE_OPSIZE(Size);
+
     /* Fetch the offset */
     if (!Fast486FetchByte(State, (PUCHAR)&Offset))
     {
@@ -684,8 +688,14 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeShortConditionalJmp)
 
     if (Jump)
     {
-        /* Move the instruction pointer */        
+        /* Move the instruction pointer */
         State->InstPtr.Long += Offset;
+
+        if (!Size)
+        {
+            /* Clear the top half of EIP */
+            State->InstPtr.Long &= 0xFFFF;
+        }
     }
 
     /* Return success */
@@ -906,7 +916,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeInByte)
     }
 
     /* Read a byte from the I/O port */
-    State->IoReadCallback(State, Port, &Data, sizeof(UCHAR));
+    State->IoReadCallback(State, Port, &Data, 1, sizeof(UCHAR));
 
     /* Store the result in AL */
     State->GeneralRegs[FAST486_REG_EAX].LowByte = Data;
@@ -950,7 +960,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeIn)
         ULONG Data;
 
         /* Read a dword from the I/O port */
-        State->IoReadCallback(State, Port, &Data, sizeof(ULONG));
+        State->IoReadCallback(State, Port, &Data, 1, sizeof(ULONG));
 
         /* Store the value in EAX */
         State->GeneralRegs[FAST486_REG_EAX].Long = Data;
@@ -960,7 +970,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeIn)
         USHORT Data;
 
         /* Read a word from the I/O port */
-        State->IoReadCallback(State, Port, &Data, sizeof(USHORT));
+        State->IoReadCallback(State, Port, &Data, 1, sizeof(USHORT));
 
         /* Store the value in AX */
         State->GeneralRegs[FAST486_REG_EAX].LowWord = Data;
@@ -997,9 +1007,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeOutByte)
 
     /* Read the value from AL */
     Data = State->GeneralRegs[FAST486_REG_EAX].LowByte;
-    
+
     /* Write the byte to the I/O port */
-    State->IoWriteCallback(State, Port, &Data, sizeof(UCHAR));
+    State->IoWriteCallback(State, Port, &Data, 1, sizeof(UCHAR));
 
     return TRUE;
 }
@@ -1041,7 +1051,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeOut)
         ULONG Data = State->GeneralRegs[FAST486_REG_EAX].Long;
 
         /* Write a dword to the I/O port */
-        State->IoReadCallback(State, Port, &Data, sizeof(ULONG));
+        State->IoWriteCallback(State, Port, &Data, 1, sizeof(ULONG));
     }
     else
     {
@@ -1049,7 +1059,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeOut)
         USHORT Data = State->GeneralRegs[FAST486_REG_EAX].LowWord;
 
         /* Write a word to the I/O port */
-        State->IoWriteCallback(State, Port, &Data, sizeof(USHORT));
+        State->IoWriteCallback(State, Port, &Data, 1, sizeof(USHORT));
     }
 
     return TRUE;
@@ -1058,6 +1068,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeOut)
 FAST486_OPCODE_HANDLER(Fast486OpcodeShortJump)
 {
     CHAR Offset = 0;
+    BOOLEAN Size = State->SegmentRegs[FAST486_REG_CS].Size;
+
+    TOGGLE_OPSIZE(Size);
 
     /* Make sure this is the right instruction */
     ASSERT(Opcode == 0xEB);
@@ -1069,9 +1082,15 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeShortJump)
         return FALSE;
     }
 
-    /* Move the instruction pointer */        
+    /* Move the instruction pointer */
     State->InstPtr.Long += Offset;
 
+    if (!Size)
+    {
+        /* Clear the top half of EIP */
+        State->InstPtr.Long &= 0xFFFF;
+    }
+
     return TRUE;
 }
 
@@ -1186,9 +1205,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAddByteModrm)
     State->Flags.Cf = (Result < FirstValue) && (Result < SecondValue);
     State->Flags.Of = ((FirstValue & SIGN_FLAG_BYTE) == (SecondValue & SIGN_FLAG_BYTE))
                       && ((FirstValue & SIGN_FLAG_BYTE) != (Result & SIGN_FLAG_BYTE));
-    State->Flags.Af = (((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) ? TRUE : FALSE;
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Af = ((((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) != 0);
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Write back the result */
@@ -1231,7 +1250,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAddModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         /* Calculate the result */
         Result = FirstValue + SecondValue;
 
@@ -1239,9 +1258,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAddModrm)
         State->Flags.Cf = (Result < FirstValue) && (Result < SecondValue);
         State->Flags.Of = ((FirstValue & SIGN_FLAG_LONG) == (SecondValue & SIGN_FLAG_LONG))
                           && ((FirstValue & SIGN_FLAG_LONG) != (Result & SIGN_FLAG_LONG));
-        State->Flags.Af = (((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) ? TRUE : FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Af = ((((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) != 0);
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -1262,7 +1281,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAddModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         /* Calculate the result */
         Result = FirstValue + SecondValue;
 
@@ -1270,9 +1289,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAddModrm)
         State->Flags.Cf = (Result < FirstValue) && (Result < SecondValue);
         State->Flags.Of = ((FirstValue & SIGN_FLAG_WORD) == (SecondValue & SIGN_FLAG_WORD))
                           && ((FirstValue & SIGN_FLAG_WORD) != (Result & SIGN_FLAG_WORD));
-        State->Flags.Af = (((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) ? TRUE : FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Af = ((((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) != 0);
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -1311,9 +1330,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAddAl)
     State->Flags.Cf = (Result < FirstValue) && (Result < SecondValue);
     State->Flags.Of = ((FirstValue & SIGN_FLAG_BYTE) == (SecondValue & SIGN_FLAG_BYTE))
                       && ((FirstValue & SIGN_FLAG_BYTE) != (Result & SIGN_FLAG_BYTE));
-    State->Flags.Af = (((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) ? TRUE : FALSE;
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Af = ((((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) != 0);
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Write back the result */
@@ -1350,9 +1369,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAddEax)
         State->Flags.Cf = (Result < FirstValue) && (Result < SecondValue);
         State->Flags.Of = ((FirstValue & SIGN_FLAG_LONG) == (SecondValue & SIGN_FLAG_LONG))
                           && ((FirstValue & SIGN_FLAG_LONG) != (Result & SIGN_FLAG_LONG));
-        State->Flags.Af = (((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) ? TRUE : FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Af = ((((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) != 0);
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -1376,9 +1395,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAddEax)
         State->Flags.Cf = (Result < FirstValue) && (Result < SecondValue);
         State->Flags.Of = ((FirstValue & SIGN_FLAG_WORD) == (SecondValue & SIGN_FLAG_WORD))
                           && ((FirstValue & SIGN_FLAG_WORD) != (Result & SIGN_FLAG_WORD));
-        State->Flags.Af = (((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) ? TRUE : FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Af = ((((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) != 0);
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -1421,8 +1440,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeOrByteModrm)
     /* Update the flags */
     State->Flags.Cf = FALSE;
     State->Flags.Of = FALSE;
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Write back the result */
@@ -1465,15 +1484,15 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeOrModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         /* Calculate the result */
         Result = FirstValue | SecondValue;
 
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -1494,15 +1513,15 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeOrModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         /* Calculate the result */
         Result = FirstValue | SecondValue;
 
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -1540,8 +1559,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeOrAl)
     /* Update the flags */
     State->Flags.Cf = FALSE;
     State->Flags.Of = FALSE;
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Write back the result */
@@ -1577,8 +1596,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeOrEax)
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -1601,8 +1620,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeOrEax)
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -1645,8 +1664,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAndByteModrm)
     /* Update the flags */
     State->Flags.Cf = FALSE;
     State->Flags.Of = FALSE;
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Write back the result */
@@ -1689,15 +1708,15 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAndModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         /* Calculate the result */
         Result = FirstValue & SecondValue;
 
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -1718,15 +1737,15 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAndModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         /* Calculate the result */
         Result = FirstValue & SecondValue;
 
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -1759,8 +1778,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAndAl)
     /* Update the flags */
     State->Flags.Cf = FALSE;
     State->Flags.Of = FALSE;
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Write back the result */
@@ -1796,8 +1815,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAndEax)
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -1820,8 +1839,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAndEax)
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -1864,8 +1883,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeXorByteModrm)
     /* Update the flags */
     State->Flags.Cf = FALSE;
     State->Flags.Of = FALSE;
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Write back the result */
@@ -1908,15 +1927,15 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeXorModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         /* Calculate the result */
         Result = FirstValue ^ SecondValue;
 
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -1937,15 +1956,15 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeXorModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         /* Calculate the result */
         Result = FirstValue ^ SecondValue;
 
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -1983,8 +2002,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeXorAl)
     /* Update the flags */
     State->Flags.Cf = FALSE;
     State->Flags.Of = FALSE;
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Write back the result */
@@ -2020,8 +2039,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeXorEax)
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -2044,8 +2063,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeXorEax)
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -2087,8 +2106,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeTestByteModrm)
     /* Update the flags */
     State->Flags.Cf = FALSE;
     State->Flags.Of = FALSE;
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* The result is discarded */
@@ -2128,15 +2147,15 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeTestModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         /* Calculate the result */
         Result = FirstValue & SecondValue;
 
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
     }
     else
@@ -2151,15 +2170,15 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeTestModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         /* Calculate the result */
         Result = FirstValue & SecondValue;
 
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
     }
 
@@ -2194,8 +2213,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeTestAl)
     /* Update the flags */
     State->Flags.Cf = FALSE;
     State->Flags.Of = FALSE;
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* The result is discarded */
@@ -2229,8 +2248,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeTestEax)
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
     }
     else
@@ -2250,8 +2269,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeTestEax)
         /* Update the flags */
         State->Flags.Cf = FALSE;
         State->Flags.Of = FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
     }
 
@@ -2375,7 +2394,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeXchgModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         /* Write the value from the register to the R/M */
         if (!Fast486WriteModrmWordOperands(State,
                                            &ModRegRm,
@@ -2465,9 +2484,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAdcByteModrm)
     State->Flags.Cf = State->Flags.Cf || ((Result < FirstValue) && (Result < SecondValue));
     State->Flags.Of = ((FirstValue & SIGN_FLAG_BYTE) == (SecondValue & SIGN_FLAG_BYTE))
                       && ((FirstValue & SIGN_FLAG_BYTE) != (Result & SIGN_FLAG_BYTE));
-    State->Flags.Af = (((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) ? TRUE : FALSE;
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Af = ((FirstValue ^ SecondValue ^ Result) & 0x10) != 0;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Write back the result */
@@ -2510,7 +2529,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAdcModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         /* Calculate the result */
         Result = FirstValue + SecondValue + State->Flags.Cf;
 
@@ -2522,9 +2541,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAdcModrm)
         State->Flags.Cf = State->Flags.Cf || ((Result < FirstValue) && (Result < SecondValue));
         State->Flags.Of = ((FirstValue & SIGN_FLAG_LONG) == (SecondValue & SIGN_FLAG_LONG))
                           && ((FirstValue & SIGN_FLAG_LONG) != (Result & SIGN_FLAG_LONG));
-        State->Flags.Af = (((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) ? TRUE : FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Af = ((FirstValue ^ SecondValue ^ Result) & 0x10) != 0;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -2545,7 +2564,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAdcModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         /* Calculate the result */
         Result = FirstValue + SecondValue + State->Flags.Cf;
 
@@ -2557,9 +2576,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAdcModrm)
         State->Flags.Cf = State->Flags.Cf || ((Result < FirstValue) && (Result < SecondValue));
         State->Flags.Of = ((FirstValue & SIGN_FLAG_WORD) == (SecondValue & SIGN_FLAG_WORD))
                           && ((FirstValue & SIGN_FLAG_WORD) != (Result & SIGN_FLAG_WORD));
-        State->Flags.Af = (((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) ? TRUE : FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Af = ((FirstValue ^ SecondValue ^ Result) & 0x10) != 0;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -2603,9 +2622,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAdcAl)
     State->Flags.Cf = State->Flags.Cf || ((Result < FirstValue) && (Result < SecondValue));
     State->Flags.Of = ((FirstValue & SIGN_FLAG_BYTE) == (SecondValue & SIGN_FLAG_BYTE))
                       && ((FirstValue & SIGN_FLAG_BYTE) != (Result & SIGN_FLAG_BYTE));
-    State->Flags.Af = (((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) ? TRUE : FALSE;
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Af = ((FirstValue ^ SecondValue ^ Result) & 0x10) != 0;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Write back the result */
@@ -2646,9 +2665,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAdcEax)
         State->Flags.Cf = State->Flags.Cf || ((Result < FirstValue) && (Result < SecondValue));
         State->Flags.Of = ((FirstValue & SIGN_FLAG_LONG) == (SecondValue & SIGN_FLAG_LONG))
                           && ((FirstValue & SIGN_FLAG_LONG) != (Result & SIGN_FLAG_LONG));
-        State->Flags.Af = (((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) ? TRUE : FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Af = ((FirstValue ^ SecondValue ^ Result) & 0x10) != 0;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -2676,9 +2695,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAdcEax)
         State->Flags.Cf = State->Flags.Cf || ((Result < FirstValue) && (Result < SecondValue));
         State->Flags.Of = ((FirstValue & SIGN_FLAG_WORD) == (SecondValue & SIGN_FLAG_WORD))
                           && ((FirstValue & SIGN_FLAG_WORD) != (Result & SIGN_FLAG_WORD));
-        State->Flags.Af = (((FirstValue & 0x0F) + (SecondValue & 0x0F)) & 0x10) ? TRUE : FALSE;
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Af = ((FirstValue ^ SecondValue ^ Result) & 0x10) != 0;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -2747,12 +2766,12 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeSbbByteModrm)
     Result = FirstValue - SecondValue - Carry;
 
     /* Update the flags */
-    State->Flags.Cf = FirstValue < (SecondValue + 1);
+    State->Flags.Cf = Carry ? (FirstValue <= SecondValue) : (FirstValue < SecondValue);
     State->Flags.Of = ((FirstValue & SIGN_FLAG_BYTE) != (SecondValue & SIGN_FLAG_BYTE))
                       && ((FirstValue & SIGN_FLAG_BYTE) != (Result & SIGN_FLAG_BYTE));
-    State->Flags.Af = (FirstValue & 0x0F) < ((SecondValue + 1) & 0x0F);
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Af = ((FirstValue ^ SecondValue ^ Result) & 0x10) != 0;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Write back the result */
@@ -2803,17 +2822,17 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeSbbModrm)
             /* Swap the order */
             SWAP(FirstValue, SecondValue);
         }
-    
+
         /* Calculate the result */
         Result = FirstValue - SecondValue - Carry;
 
         /* Update the flags */
-        State->Flags.Cf = FirstValue < (SecondValue + Carry);
+        State->Flags.Cf = Carry ? (FirstValue <= SecondValue) : (FirstValue < SecondValue);
         State->Flags.Of = ((FirstValue & SIGN_FLAG_LONG) != (SecondValue & SIGN_FLAG_LONG))
                           && ((FirstValue & SIGN_FLAG_LONG) != (Result & SIGN_FLAG_LONG));
-        State->Flags.Af = (FirstValue & 0x0F) < ((SecondValue + 1) & 0x0F);
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Af = ((FirstValue ^ SecondValue ^ Result) & 0x10) != 0;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -2834,24 +2853,24 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeSbbModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         /* Check if this is the instruction that writes to R/M */
         if (!(Opcode & FAST486_OPCODE_WRITE_REG))
         {
             /* Swap the order */
             SWAP(FirstValue, SecondValue);
         }
-    
+
         /* Calculate the result */
         Result = FirstValue - SecondValue - Carry;
 
         /* Update the flags */
-        State->Flags.Cf = FirstValue < (SecondValue + Carry);
+        State->Flags.Cf = Carry ? (FirstValue <= SecondValue) : (FirstValue < SecondValue);
         State->Flags.Of = ((FirstValue & SIGN_FLAG_WORD) != (SecondValue & SIGN_FLAG_WORD))
                           && ((FirstValue & SIGN_FLAG_WORD) != (Result & SIGN_FLAG_WORD));
-        State->Flags.Af = (FirstValue & 0x0F) < ((SecondValue + 1) & 0x0F);
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Af = ((FirstValue ^ SecondValue ^ Result) & 0x10) != 0;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -2888,12 +2907,12 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeSbbAl)
     Result = FirstValue - SecondValue - Carry;
 
     /* Update the flags */
-    State->Flags.Cf = FirstValue < (SecondValue + Carry);
+    State->Flags.Cf = Carry ? (FirstValue <= SecondValue) : (FirstValue < SecondValue);
     State->Flags.Of = ((FirstValue & SIGN_FLAG_BYTE) != (SecondValue & SIGN_FLAG_BYTE))
                       && ((FirstValue & SIGN_FLAG_BYTE) != (Result & SIGN_FLAG_BYTE));
-    State->Flags.Af = (FirstValue & 0x0F) < ((SecondValue + 1) & 0x0F);
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Af = ((FirstValue ^ SecondValue ^ Result) & 0x10) != 0;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Write back the result */
@@ -2929,12 +2948,12 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeSbbEax)
         Result = FirstValue - SecondValue - Carry;
 
         /* Update the flags */
-        State->Flags.Cf = FirstValue < (SecondValue + Carry);
+        State->Flags.Cf = Carry ? (FirstValue <= SecondValue) : (FirstValue < SecondValue);
         State->Flags.Of = ((FirstValue & SIGN_FLAG_LONG) != (SecondValue & SIGN_FLAG_LONG))
                           && ((FirstValue & SIGN_FLAG_LONG) != (Result & SIGN_FLAG_LONG));
-        State->Flags.Af = (FirstValue & 0x0F) < ((SecondValue + Carry) & 0x0F);
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Af = ((FirstValue ^ SecondValue ^ Result) & 0x10) != 0;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -2955,12 +2974,12 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeSbbEax)
         Result = FirstValue - SecondValue - Carry;
 
         /* Update the flags */
-        State->Flags.Cf = FirstValue < (SecondValue + Carry);
+        State->Flags.Cf = Carry ? (FirstValue <= SecondValue) : (FirstValue < SecondValue);
         State->Flags.Of = ((FirstValue & SIGN_FLAG_WORD) != (SecondValue & SIGN_FLAG_WORD))
                           && ((FirstValue & SIGN_FLAG_WORD) != (Result & SIGN_FLAG_WORD));
-        State->Flags.Af = (FirstValue & 0x0F) < ((SecondValue + Carry) & 0x0F);
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Af = ((FirstValue ^ SecondValue ^ Result) & 0x10) != 0;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Write back the result */
@@ -3024,6 +3043,13 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeDaa)
         State->Flags.Cf = TRUE;
     }
 
+    Value = State->GeneralRegs[FAST486_REG_EAX].LowByte;
+
+    /* Update the flags */
+    State->Flags.Sf = (Value & SIGN_FLAG_BYTE) != 0;
+    State->Flags.Zf = (Value == 0);
+    State->Flags.Pf = Fast486CalculateParity(Value);
+
     return TRUE;
 }
 
@@ -3065,12 +3091,12 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeCmpSubByteModrm)
     Result = FirstValue - SecondValue;
 
     /* Update the flags */
-    State->Flags.Cf = FirstValue < SecondValue;
+    State->Flags.Cf = (FirstValue < SecondValue);
     State->Flags.Of = ((FirstValue & SIGN_FLAG_BYTE) != (SecondValue & SIGN_FLAG_BYTE))
                       && ((FirstValue & SIGN_FLAG_BYTE) != (Result & SIGN_FLAG_BYTE));
     State->Flags.Af = (FirstValue & 0x0F) < (SecondValue & 0x0F);
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Check if this is not a CMP */
@@ -3129,17 +3155,17 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeCmpSubModrm)
             /* Swap the order */
             SWAP(FirstValue, SecondValue);
         }
-    
+
         /* Calculate the result */
         Result = FirstValue - SecondValue;
 
         /* Update the flags */
-        State->Flags.Cf = FirstValue < SecondValue;
+        State->Flags.Cf = (FirstValue < SecondValue);
         State->Flags.Of = ((FirstValue & SIGN_FLAG_LONG) != (SecondValue & SIGN_FLAG_LONG))
                           && ((FirstValue & SIGN_FLAG_LONG) != (Result & SIGN_FLAG_LONG));
         State->Flags.Af = (FirstValue & 0x0F) < (SecondValue & 0x0F);
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Check if this is not a CMP */
@@ -3169,24 +3195,24 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeCmpSubModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         /* Check if this is the instruction that writes to R/M */
         if (!(Opcode & FAST486_OPCODE_WRITE_REG))
         {
             /* Swap the order */
             SWAP(FirstValue, SecondValue);
         }
-    
+
         /* Calculate the result */
         Result = FirstValue - SecondValue;
 
         /* Update the flags */
-        State->Flags.Cf = FirstValue < SecondValue;
+        State->Flags.Cf = (FirstValue < SecondValue);
         State->Flags.Of = ((FirstValue & SIGN_FLAG_WORD) != (SecondValue & SIGN_FLAG_WORD))
                           && ((FirstValue & SIGN_FLAG_WORD) != (Result & SIGN_FLAG_WORD));
         State->Flags.Af = (FirstValue & 0x0F) < (SecondValue & 0x0F);
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Check if this is not a CMP */
@@ -3231,12 +3257,12 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeCmpSubAl)
     Result = FirstValue - SecondValue;
 
     /* Update the flags */
-    State->Flags.Cf = FirstValue < SecondValue;
+    State->Flags.Cf = (FirstValue < SecondValue);
     State->Flags.Of = ((FirstValue & SIGN_FLAG_BYTE) != (SecondValue & SIGN_FLAG_BYTE))
                       && ((FirstValue & SIGN_FLAG_BYTE) != (Result & SIGN_FLAG_BYTE));
     State->Flags.Af = (FirstValue & 0x0F) < (SecondValue & 0x0F);
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Check if this is not a CMP */
@@ -3274,12 +3300,12 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeCmpSubEax)
         Result = FirstValue - SecondValue;
 
         /* Update the flags */
-        State->Flags.Cf = FirstValue < SecondValue;
+        State->Flags.Cf = (FirstValue < SecondValue);
         State->Flags.Of = ((FirstValue & SIGN_FLAG_LONG) != (SecondValue & SIGN_FLAG_LONG))
                           && ((FirstValue & SIGN_FLAG_LONG) != (Result & SIGN_FLAG_LONG));
         State->Flags.Af = (FirstValue & 0x0F) < (SecondValue & 0x0F);
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_LONG) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Check if this is not a CMP */
@@ -3304,12 +3330,12 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeCmpSubEax)
         Result = FirstValue - SecondValue;
 
         /* Update the flags */
-        State->Flags.Cf = FirstValue < SecondValue;
+        State->Flags.Cf = (FirstValue < SecondValue);
         State->Flags.Of = ((FirstValue & SIGN_FLAG_WORD) != (SecondValue & SIGN_FLAG_WORD))
                           && ((FirstValue & SIGN_FLAG_WORD) != (Result & SIGN_FLAG_WORD));
         State->Flags.Af = (FirstValue & 0x0F) < (SecondValue & 0x0F);
-        State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-        State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
+        State->Flags.Zf = (Result == 0);
+        State->Flags.Sf = ((Result & SIGN_FLAG_WORD) != 0);
         State->Flags.Pf = Fast486CalculateParity(Result);
 
         /* Check if this is not a CMP */
@@ -3356,6 +3382,13 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeDas)
         State->Flags.Cf = TRUE;
     }
 
+    Value = State->GeneralRegs[FAST486_REG_EAX].LowByte;
+
+    /* Update the flags */
+    State->Flags.Sf = (Value & SIGN_FLAG_BYTE) != 0;
+    State->Flags.Zf = (Value == 0);
+    State->Flags.Pf = Fast486CalculateParity(Value);
+
     return TRUE;
 }
 
@@ -3370,7 +3403,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAaa)
     if (((Value & 0x0F) > 9) || State->Flags.Af)
     {
         /* Correct it */
-        State->GeneralRegs[FAST486_REG_EAX].LowByte += 0x06;
+        State->GeneralRegs[FAST486_REG_EAX].LowWord += 0x06;
         State->GeneralRegs[FAST486_REG_EAX].HighByte++;
 
         /* Set CF and AF */
@@ -3399,7 +3432,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAas)
     if (((Value & 0x0F) > 9) || State->Flags.Af)
     {
         /* Correct it */
-        State->GeneralRegs[FAST486_REG_EAX].LowByte -= 0x06;
+        State->GeneralRegs[FAST486_REG_EAX].LowWord -= 0x06;
         State->GeneralRegs[FAST486_REG_EAX].HighByte--;
 
         /* Set CF and AF */
@@ -3595,7 +3628,6 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeImulModrmImm)
     BOOLEAN OperandSize, AddressSize;
     FAST486_MOD_REG_RM ModRegRm;
     LONG Multiplier;
-    LONGLONG Product;
 
     /* Make sure this is the right instruction */
     ASSERT((Opcode & 0xFD) == 0x69);
@@ -3658,6 +3690,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeImulModrmImm)
     if (OperandSize)
     {
         LONG RegValue, Multiplicand;
+        LONGLONG Product;
 
         /* Read the operands */
         if (!Fast486ReadModrmDwordOperands(State,
@@ -3671,10 +3704,20 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeImulModrmImm)
 
         /* Multiply */
         Product = (LONGLONG)Multiplicand * (LONGLONG)Multiplier;
+
+        /* Check for carry/overflow */
+        State->Flags.Cf = State->Flags.Of = ((Product < MINLONG) || (Product > MAXLONG));
+
+        /* Write-back the result */
+        return Fast486WriteModrmDwordOperands(State,
+                                              &ModRegRm,
+                                              TRUE,
+                                              (ULONG)((LONG)Product));
     }
     else
     {
         SHORT RegValue, Multiplicand;
+        LONG Product;
 
         /* Read the operands */
         if (!Fast486ReadModrmWordOperands(State,
@@ -3687,17 +3730,17 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeImulModrmImm)
         }
 
         /* Multiply */
-        Product = (LONGLONG)Multiplicand * (LONGLONG)Multiplier;
-    }
+        Product = (LONG)Multiplicand * (LONG)Multiplier;
 
-    /* Check for carry/overflow */
-    State->Flags.Cf = State->Flags.Of = ((Product < MINLONG) || (Product > MAXLONG));
+        /* Check for carry/overflow */
+        State->Flags.Cf = State->Flags.Of = ((Product < MINSHORT) || (Product > MAXSHORT));
 
-    /* Write-back the result */
-    return Fast486WriteModrmDwordOperands(State,
-                                          &ModRegRm,
-                                          TRUE,
-                                          (ULONG)((LONG)Product));
+        /* Write-back the result */
+        return Fast486WriteModrmWordOperands(State,
+                                             &ModRegRm,
+                                             TRUE,
+                                             (USHORT)((SHORT)Product));
+    }
 }
 
 FAST486_OPCODE_HANDLER(Fast486OpcodePushByteImm)
@@ -3791,7 +3834,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeMovModrm)
 
         if (Opcode & FAST486_OPCODE_WRITE_REG) Result = SecondValue;
         else Result = FirstValue;
-    
+
         /* Write back the result */
         return Fast486WriteModrmDwordOperands(State,
                                               &ModRegRm,
@@ -3810,7 +3853,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeMovModrm)
             /* Exception occurred */
             return FALSE;
         }
-    
+
         if (Opcode & FAST486_OPCODE_WRITE_REG) Result = SecondValue;
         else Result = FirstValue;
 
@@ -3941,9 +3984,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeMovLoadSeg)
 
     if (OperandSize)
     {
-        ULONG Dummy, Selector;
+        ULONG Selector;
 
-        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Dummy, &Selector))
+        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Selector))
         {
             /* Exception occurred */
             return FALSE;
@@ -3953,9 +3996,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeMovLoadSeg)
     }
     else
     {
-        USHORT Dummy, Selector;
+        USHORT Selector;
 
-        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Dummy, &Selector))
+        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, &Selector))
         {
             /* Exception occurred */
             return FALSE;
@@ -4121,121 +4164,37 @@ FAST486_OPCODE_HANDLER(Fast486OpcodePopFlags)
 {
     BOOLEAN Size = State->SegmentRegs[FAST486_REG_CS].Size;
     INT Cpl = Fast486GetCurrentPrivLevel(State);
-    ULONG NewFlags;
+    FAST486_FLAGS_REG NewFlags;
 
     NO_LOCK_PREFIX();
     TOGGLE_OPSIZE(Size);
 
     /* Pop the new flags */
-    if (!Fast486StackPop(State, &NewFlags))
+    if (!Fast486StackPop(State, &NewFlags.Long))
     {
         /* Exception occurred */
         return FALSE;
     }
 
-    if (!State->Flags.Vm)
+    if (State->Flags.Vm && (State->Flags.Iopl != 3))
     {
-        /* Check the current privilege level */
-        if (Cpl == 0)
-        {
-            /* Supervisor */
-
-            /* Set the flags */
-            if (Size)
-            {
-                /* Memorize the old state of RF */
-                BOOLEAN OldRf = State->Flags.Rf;
-
-                State->Flags.Long = NewFlags;
-
-                /* Restore VM and RF */
-                State->Flags.Vm = FALSE;
-                State->Flags.Rf = OldRf;
-
-                /* Clear VIF and VIP */
-                State->Flags.Vif = State->Flags.Vip = FALSE;
-            }
-            else State->Flags.LowWord = LOWORD(NewFlags);
-
-            /* Restore the reserved bits */
-            State->Flags.AlwaysSet = TRUE;
-            State->Flags.Reserved0 = FALSE;
-            State->Flags.Reserved1 = FALSE;
-        }
-        else
-        {
-            /* User */
-
-            /* Memorize the old state of IF and IOPL */
-            BOOLEAN OldIf = State->Flags.If;
-            UINT OldIopl = State->Flags.Iopl;
-
-            /* Set the flags */
-            if (Size)
-            {
-                /* Memorize the old state of RF */
-                BOOLEAN OldRf = State->Flags.Rf;
-
-                State->Flags.Long = NewFlags;
-
-                /* Restore VM and RF */
-                State->Flags.Vm = FALSE;
-                State->Flags.Rf = OldRf;
-
-                /* Clear VIF and VIP */
-                State->Flags.Vif = State->Flags.Vip = FALSE;
-            }
-            else State->Flags.LowWord = LOWORD(NewFlags);
-
-            /* Restore the reserved bits and IOPL */
-            State->Flags.AlwaysSet = TRUE;
-            State->Flags.Reserved0 = FALSE;
-            State->Flags.Reserved1 = FALSE;
-            State->Flags.Iopl = OldIopl;
-
-            /* Check if the user doesn't have the privilege to change IF */
-            if (Cpl > State->Flags.Iopl)
-            {
-                /* Restore IF */
-                State->Flags.If = OldIf;
-            }
-        }
+        /* Call the VM86 monitor */
+        Fast486ExceptionWithErrorCode(State, FAST486_EXCEPTION_GP, 0);
+        return TRUE;
     }
-    else
-    {
-        /* Check the IOPL */
-        if (State->Flags.Iopl == 3)
-        {
-            if (Size)
-            {
-                /* Memorize the old state of RF, VIF and VIP */
-                BOOLEAN OldRf = State->Flags.Rf;
-                BOOLEAN OldVif = State->Flags.Vif;
-                BOOLEAN OldVip = State->Flags.Vip;
-
-                State->Flags.Long = NewFlags;
-
-                /* Restore VM, RF, VIF and VIP */
-                State->Flags.Vm = TRUE;
-                State->Flags.Rf = OldRf;
-                State->Flags.Vif = OldVif;
-                State->Flags.Vip = OldVip;
-            }
-            else State->Flags.LowWord = LOWORD(NewFlags);
 
-            /* Restore the reserved bits and IOPL */
-            State->Flags.AlwaysSet = TRUE;
-            State->Flags.Reserved0 = FALSE;
-            State->Flags.Reserved1 = FALSE;
-            State->Flags.Iopl = 3;
-        }
-        else
-        {
-            /* Call the VM86 monitor */
-            Fast486ExceptionWithErrorCode(State, FAST486_EXCEPTION_GP, 0);
-        }
-        
-    }
+    State->Flags.Cf = NewFlags.Cf;
+    State->Flags.Pf = NewFlags.Pf;
+    State->Flags.Af = NewFlags.Af;
+    State->Flags.Zf = NewFlags.Zf;
+    State->Flags.Sf = NewFlags.Sf;
+    State->Flags.Tf = NewFlags.Tf;
+    State->Flags.Df = NewFlags.Df;
+    State->Flags.Of = NewFlags.Of;
+    State->Flags.Nt = NewFlags.Nt;
+
+    if (Cpl == 0) State->Flags.Iopl = NewFlags.Iopl;
+    if (Cpl <= State->Flags.Iopl) State->Flags.If = NewFlags.If;
 
     return TRUE;
 }
@@ -4314,6 +4273,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeLdsLes)
 
     OperandSize = AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
 
+    TOGGLE_OPSIZE(OperandSize);
     TOGGLE_ADSIZE(AddressSize);
 
     /* Get the operands */
@@ -4847,8 +4807,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAam)
     State->GeneralRegs[FAST486_REG_EAX].LowByte = Value %= Base;
 
     /* Update flags */
-    State->Flags.Zf = (Value == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Value & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Af = FALSE;
+    State->Flags.Zf = (Value == 0);
+    State->Flags.Sf = ((Value & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Value);
 
     return TRUE;
@@ -4870,11 +4831,12 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeAad)
 
     /* Adjust */
     Value += State->GeneralRegs[FAST486_REG_EAX].HighByte * Base;
-    State->GeneralRegs[FAST486_REG_EAX].LowByte = Value;
+    State->GeneralRegs[FAST486_REG_EAX].LowWord = Value;
 
     /* Update flags */
-    State->Flags.Zf = (Value == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Value & SIGN_FLAG_BYTE) ? TRUE : FALSE;
+    State->Flags.Af = FALSE;
+    State->Flags.Zf = (Value == 0);
+    State->Flags.Sf = ((Value & SIGN_FLAG_BYTE) != 0);
     State->Flags.Pf = Fast486CalculateParity(Value);
 
     return TRUE;
@@ -4890,8 +4852,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeXlat)
     /* Read a byte from DS:[(E)BX + AL] */
     if (!Fast486ReadMemory(State,
                            FAST486_REG_DS,
-                           AddressSize ? State->GeneralRegs[FAST486_REG_EBX].Long
-                                       : State->GeneralRegs[FAST486_REG_EBX].LowWord
+                           (AddressSize ? State->GeneralRegs[FAST486_REG_EBX].Long
+                                        : State->GeneralRegs[FAST486_REG_EBX].LowWord)
                            + State->GeneralRegs[FAST486_REG_EAX].LowByte,
                            FALSE,
                            &Value,
@@ -4918,7 +4880,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeLoop)
     ASSERT((Opcode >= 0xE0) && (Opcode <= 0xE2));
 
     NO_LOCK_PREFIX();
-    TOGGLE_OPSIZE(Size);
+    TOGGLE_ADSIZE(Size);
 
     if (Size) Condition = ((--State->GeneralRegs[FAST486_REG_ECX].Long) != 0);
     else Condition = ((--State->GeneralRegs[FAST486_REG_ECX].LowWord) != 0);
@@ -4945,7 +4907,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeLoop)
     if (Condition)
     {
         /* Move the instruction pointer */
-        State->InstPtr.Long += Offset;
+        if (Size) State->InstPtr.Long += Offset;
+        else State->InstPtr.LowWord += Offset;
     }
 
     return TRUE;
@@ -4961,7 +4924,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeJecxz)
     ASSERT(Opcode == 0xE3);
 
     NO_LOCK_PREFIX();
-    TOGGLE_OPSIZE(Size);
+    TOGGLE_ADSIZE(Size);
 
     if (Size) Condition = (State->GeneralRegs[FAST486_REG_ECX].Long == 0);
     else Condition = (State->GeneralRegs[FAST486_REG_ECX].LowWord == 0);
@@ -4975,8 +4938,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeJecxz)
 
     if (Condition)
     {
-        /* Move the instruction pointer */        
-        State->InstPtr.Long += Offset;
+        /* Move the instruction pointer */
+        if (Size) State->InstPtr.Long += Offset;
+        else State->InstPtr.LowWord += Offset;
     }
 
     return TRUE;
@@ -5010,7 +4974,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeCall)
             return FALSE;
         }
 
-        /* Move the instruction pointer */        
+        /* Move the instruction pointer */
         State->InstPtr.Long += Offset;
     }
     else
@@ -5031,7 +4995,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeCall)
             return FALSE;
         }
 
-        /* Move the instruction pointer */        
+        /* Move the instruction pointer */
         State->InstPtr.LowWord += Offset;
     }
 
@@ -5059,7 +5023,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeJmp)
             return FALSE;
         }
 
-        /* Move the instruction pointer */        
+        /* Move the instruction pointer */
         State->InstPtr.Long += Offset;
     }
     else
@@ -5073,8 +5037,11 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeJmp)
             return FALSE;
         }
 
-        /* Move the instruction pointer */        
-        State->InstPtr.LowWord += Offset;
+        /* Move the instruction pointer */
+        State->InstPtr.Long += Offset;
+
+        /* Clear the top half of EIP */
+        State->InstPtr.Long &= 0xFFFF;
     }
 
     return TRUE;
@@ -5124,24 +5091,23 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeJmpAbs)
         return FALSE;
     }
 
-    /* Load new (E)IP */
-    if (Size) State->InstPtr.Long = Offset;
-    else State->InstPtr.LowWord = LOWORD(Offset);
+    /* Load new EIP */
+    State->InstPtr.Long = Offset;
 
     return TRUE;
 }
 
 FAST486_OPCODE_HANDLER(Fast486OpcodeMovAlOffset)
 {
-    BOOLEAN Size = State->SegmentRegs[FAST486_REG_CS].Size;
+    BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
     ULONG Offset;
 
     /* Make sure this is the right instruction */
     ASSERT(Opcode == 0xA0);
 
-    TOGGLE_OPSIZE(Size);
+    TOGGLE_ADSIZE(AddressSize);
 
-    if (Size)
+    if (AddressSize)
     {
         if (!Fast486FetchDword(State, &Offset))
         {
@@ -5174,14 +5140,17 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeMovAlOffset)
 
 FAST486_OPCODE_HANDLER(Fast486OpcodeMovEaxOffset)
 {
-    BOOLEAN Size = State->SegmentRegs[FAST486_REG_CS].Size;
+    BOOLEAN OperandSize, AddressSize;
+
+    OperandSize = AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
 
     /* Make sure this is the right instruction */
     ASSERT(Opcode == 0xA1);
 
-    TOGGLE_OPSIZE(Size);
+    TOGGLE_OPSIZE(OperandSize);
+    TOGGLE_ADSIZE(AddressSize);
 
-    if (Size)
+    if (AddressSize)
     {
         ULONG Offset;
 
@@ -5192,13 +5161,26 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeMovEaxOffset)
         }
 
         /* Read from memory */
-        return Fast486ReadMemory(State,
-                                 (State->PrefixFlags & FAST486_PREFIX_SEG) ?
-                                 State->SegmentOverride : FAST486_REG_DS,
-                                 Offset,
-                                 FALSE,
-                                 &State->GeneralRegs[FAST486_REG_EAX].Long,
-                                 sizeof(ULONG));
+        if (OperandSize)
+        {
+            return Fast486ReadMemory(State,
+                                     (State->PrefixFlags & FAST486_PREFIX_SEG) ?
+                                     State->SegmentOverride : FAST486_REG_DS,
+                                     Offset,
+                                     FALSE,
+                                     &State->GeneralRegs[FAST486_REG_EAX].Long,
+                                     sizeof(ULONG));
+        }
+        else
+        {
+            return Fast486ReadMemory(State,
+                                     (State->PrefixFlags & FAST486_PREFIX_SEG) ?
+                                     State->SegmentOverride : FAST486_REG_DS,
+                                     Offset,
+                                     FALSE,
+                                     &State->GeneralRegs[FAST486_REG_EAX].LowWord,
+                                     sizeof(USHORT));
+        }
     }
     else
     {
@@ -5211,27 +5193,40 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeMovEaxOffset)
         }
 
         /* Read from memory */
-        return Fast486ReadMemory(State,
-                                 (State->PrefixFlags & FAST486_PREFIX_SEG) ?
-                                 State->SegmentOverride : FAST486_REG_DS,
-                                 Offset,
-                                 FALSE,
-                                 &State->GeneralRegs[FAST486_REG_EAX].LowWord,
-                                 sizeof(USHORT));
+        if (OperandSize)
+        {
+            return Fast486ReadMemory(State,
+                                     (State->PrefixFlags & FAST486_PREFIX_SEG) ?
+                                     State->SegmentOverride : FAST486_REG_DS,
+                                     Offset,
+                                     FALSE,
+                                     &State->GeneralRegs[FAST486_REG_EAX].Long,
+                                     sizeof(ULONG));
+        }
+        else
+        {
+            return Fast486ReadMemory(State,
+                                     (State->PrefixFlags & FAST486_PREFIX_SEG) ?
+                                     State->SegmentOverride : FAST486_REG_DS,
+                                     Offset,
+                                     FALSE,
+                                     &State->GeneralRegs[FAST486_REG_EAX].LowWord,
+                                     sizeof(USHORT));
+        }
     }
 }
 
 FAST486_OPCODE_HANDLER(Fast486OpcodeMovOffsetAl)
 {
-    BOOLEAN Size = State->SegmentRegs[FAST486_REG_CS].Size;
+    BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
     ULONG Offset;
 
     /* Make sure this is the right instruction */
     ASSERT(Opcode == 0xA2);
 
-    TOGGLE_OPSIZE(Size);
+    TOGGLE_ADSIZE(AddressSize);
 
-    if (Size)
+    if (AddressSize)
     {
         if (!Fast486FetchDword(State, &Offset))
         {
@@ -5263,14 +5258,17 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeMovOffsetAl)
 
 FAST486_OPCODE_HANDLER(Fast486OpcodeMovOffsetEax)
 {
-    BOOLEAN Size = State->SegmentRegs[FAST486_REG_CS].Size;
+    BOOLEAN OperandSize, AddressSize;
+    
+    OperandSize = AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
 
     /* Make sure this is the right instruction */
     ASSERT(Opcode == 0xA3);
 
-    TOGGLE_OPSIZE(Size);
+    TOGGLE_OPSIZE(OperandSize);
+    TOGGLE_ADSIZE(AddressSize);
 
-    if (Size)
+    if (AddressSize)
     {
         ULONG Offset;
 
@@ -5281,12 +5279,24 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeMovOffsetEax)
         }
 
         /* Write to memory */
-        return Fast486WriteMemory(State,
-                                  (State->PrefixFlags & FAST486_PREFIX_SEG) ?
-                                  State->SegmentOverride : FAST486_REG_DS,
-                                  Offset,
-                                  &State->GeneralRegs[FAST486_REG_EAX].Long,
-                                  sizeof(ULONG));
+        if (OperandSize)
+        {
+            return Fast486WriteMemory(State,
+                                      (State->PrefixFlags & FAST486_PREFIX_SEG) ?
+                                      State->SegmentOverride : FAST486_REG_DS,
+                                      Offset,
+                                      &State->GeneralRegs[FAST486_REG_EAX].Long,
+                                      sizeof(ULONG));
+        }
+        else
+        {
+            return Fast486WriteMemory(State,
+                                      (State->PrefixFlags & FAST486_PREFIX_SEG) ?
+                                      State->SegmentOverride : FAST486_REG_DS,
+                                      Offset,
+                                      &State->GeneralRegs[FAST486_REG_EAX].LowWord,
+                                      sizeof(USHORT));
+        }
     }
     else
     {
@@ -5299,12 +5309,24 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeMovOffsetEax)
         }
 
         /* Write to memory */
-        return Fast486WriteMemory(State,
-                                  (State->PrefixFlags & FAST486_PREFIX_SEG) ?
-                                  State->SegmentOverride : FAST486_REG_DS,
-                                  Offset,
-                                  &State->GeneralRegs[FAST486_REG_EAX].LowWord,
-                                  sizeof(USHORT));
+        if (OperandSize)
+        {
+            return Fast486WriteMemory(State,
+                                      (State->PrefixFlags & FAST486_PREFIX_SEG) ?
+                                      State->SegmentOverride : FAST486_REG_DS,
+                                      Offset,
+                                      &State->GeneralRegs[FAST486_REG_EAX].Long,
+                                      sizeof(ULONG));
+        }
+        else
+        {
+            return Fast486WriteMemory(State,
+                                      (State->PrefixFlags & FAST486_PREFIX_SEG) ?
+                                      State->SegmentOverride : FAST486_REG_DS,
+                                      Offset,
+                                      &State->GeneralRegs[FAST486_REG_EAX].LowWord,
+                                      sizeof(USHORT));
+        }
     }
 }
 
@@ -5348,7 +5370,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeMovs)
     if (State->PrefixFlags & FAST486_PREFIX_REP)
     {
         UCHAR Block[STRING_BLOCK_SIZE];
-        ULONG Count = OperandSize ? State->GeneralRegs[FAST486_REG_ECX].Long
+        ULONG Count = AddressSize ? State->GeneralRegs[FAST486_REG_ECX].Long
                                   : State->GeneralRegs[FAST486_REG_ECX].LowWord;
 
         /* Clear the memory block */
@@ -5399,7 +5421,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeMovs)
                                    Processed * DataSize))
             {
                 /* Set ECX */
-                if (OperandSize) State->GeneralRegs[FAST486_REG_ECX].Long = Count;
+                if (AddressSize) State->GeneralRegs[FAST486_REG_ECX].Long = Count;
                 else State->GeneralRegs[FAST486_REG_ECX].LowWord = LOWORD(Count);
 
                 /* Exception occurred */
@@ -5415,7 +5437,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeMovs)
                                     Processed * DataSize))
             {
                 /* Set ECX */
-                if (OperandSize) State->GeneralRegs[FAST486_REG_ECX].Long = Count;
+                if (AddressSize) State->GeneralRegs[FAST486_REG_ECX].Long = Count;
                 else State->GeneralRegs[FAST486_REG_ECX].LowWord = LOWORD(Count);
 
                 /* Exception occurred */
@@ -5442,7 +5464,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeMovs)
         }
 
         /* Clear ECX */
-        if (OperandSize) State->GeneralRegs[FAST486_REG_ECX].Long = 0;
+        if (AddressSize) State->GeneralRegs[FAST486_REG_ECX].Long = 0;
         else State->GeneralRegs[FAST486_REG_ECX].LowWord = 0;
     }
     else
@@ -5473,7 +5495,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeMovs)
         }
 
         /* Increment/decrement ESI and EDI */
-        if (OperandSize)
+        if (AddressSize)
         {
             if (!State->Flags.Df)
             {
@@ -5531,8 +5553,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeCmps)
     else DataSize = OperandSize ? sizeof(ULONG) : sizeof(USHORT);
 
     /* Calculate the mask and sign flag */
-    DataMask = (1 << (DataSize * 8)) - 1;
     SignFlag = 1 << ((DataSize * 8) - 1);
+    DataMask = SignFlag | (SignFlag - 1);
 
     /* Read from the first source operand */
     if (!Fast486ReadMemory(State,
@@ -5566,16 +5588,16 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeCmps)
     Result = (FirstValue - SecondValue) & DataMask;
 
     /* Update the flags */
-    State->Flags.Cf = FirstValue < SecondValue;
+    State->Flags.Cf = (FirstValue < SecondValue);
     State->Flags.Of = ((FirstValue & SignFlag) != (SecondValue & SignFlag))
                       && ((FirstValue & SignFlag) != (Result & SignFlag));
     State->Flags.Af = (FirstValue & 0x0F) < (SecondValue & 0x0F);
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SignFlag) ? TRUE : FALSE;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SignFlag) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Increment/decrement ESI and EDI */
-    if (OperandSize)
+    if (AddressSize)
     {
         if (!State->Flags.Df)
         {
@@ -5607,8 +5629,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeCmps)
         || (State->PrefixFlags & FAST486_PREFIX_REPNZ))
     {
         BOOLEAN Repeat = TRUE;
-        
-        if (OperandSize)
+
+        if (AddressSize)
         {
             if ((--State->GeneralRegs[FAST486_REG_ECX].Long) == 0)
             {
@@ -5663,7 +5685,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeStos)
     if (State->PrefixFlags & FAST486_PREFIX_REP)
     {
         UCHAR Block[STRING_BLOCK_SIZE];
-        ULONG Count = OperandSize ? State->GeneralRegs[FAST486_REG_ECX].Long
+        ULONG Count = AddressSize ? State->GeneralRegs[FAST486_REG_ECX].Long
                                   : State->GeneralRegs[FAST486_REG_ECX].LowWord;
 
         /* Fill the memory block with the data */
@@ -5720,7 +5742,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeStos)
                                     Processed * DataSize))
             {
                 /* Set ECX */
-                if (OperandSize) State->GeneralRegs[FAST486_REG_ECX].Long = Count;
+                if (AddressSize) State->GeneralRegs[FAST486_REG_ECX].Long = Count;
                 else State->GeneralRegs[FAST486_REG_ECX].LowWord = LOWORD(Count);
 
                 /* Exception occurred */
@@ -5739,7 +5761,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeStos)
         }
 
         /* Clear ECX */
-        if (OperandSize) State->GeneralRegs[FAST486_REG_ECX].Long = 0;
+        if (AddressSize) State->GeneralRegs[FAST486_REG_ECX].Long = 0;
         else State->GeneralRegs[FAST486_REG_ECX].LowWord = 0;
     }
     else
@@ -5757,7 +5779,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeStos)
         }
 
         /* Increment/decrement EDI */
-        if (OperandSize)
+        if (AddressSize)
         {
             if (!State->Flags.Df) State->GeneralRegs[FAST486_REG_EDI].Long += DataSize;
             else State->GeneralRegs[FAST486_REG_EDI].Long -= DataSize;
@@ -5799,7 +5821,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeLods)
 
     if (State->PrefixFlags & FAST486_PREFIX_REP)
     {
-        ULONG Count = OperandSize ? State->GeneralRegs[FAST486_REG_ECX].Long
+        ULONG Count = AddressSize ? State->GeneralRegs[FAST486_REG_ECX].Long
                                   : State->GeneralRegs[FAST486_REG_ECX].LowWord;
 
         /* If the count is 0, do nothing */
@@ -5816,6 +5838,10 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeLods)
             if (AddressSize) State->GeneralRegs[FAST486_REG_ESI].Long -= (Count - 1) * DataSize;
             else State->GeneralRegs[FAST486_REG_ESI].LowWord -= (Count - 1) * DataSize;
         }
+
+        /* Clear ECX */
+        if (AddressSize) State->GeneralRegs[FAST486_REG_ECX].Long = 0;
+        else State->GeneralRegs[FAST486_REG_ECX].LowWord = 0;
     }
 
     /* Read from the source operand */
@@ -5832,7 +5858,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeLods)
     }
 
     /* Increment/decrement ESI */
-    if (OperandSize)
+    if (AddressSize)
     {
         if (!State->Flags.Df) State->GeneralRegs[FAST486_REG_ESI].Long += DataSize;
         else State->GeneralRegs[FAST486_REG_ESI].Long -= DataSize;
@@ -5868,8 +5894,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeScas)
     else DataSize = OperandSize ? sizeof(ULONG) : sizeof(USHORT);
 
     /* Calculate the mask and sign flag */
-    DataMask = (1 << (DataSize * 8)) - 1;
     SignFlag = 1 << ((DataSize * 8) - 1);
+    DataMask = SignFlag | (SignFlag - 1);
 
     /* Read from the source operand */
     if (!Fast486ReadMemory(State,
@@ -5890,16 +5916,16 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeScas)
     Result = (FirstValue - SecondValue) & DataMask;
 
     /* Update the flags */
-    State->Flags.Cf = FirstValue < SecondValue;
+    State->Flags.Cf = (FirstValue < SecondValue);
     State->Flags.Of = ((FirstValue & SignFlag) != (SecondValue & SignFlag))
                       && ((FirstValue & SignFlag) != (Result & SignFlag));
     State->Flags.Af = (FirstValue & 0x0F) < (SecondValue & 0x0F);
-    State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
-    State->Flags.Sf = (Result & SignFlag) ? TRUE : FALSE;
+    State->Flags.Zf = (Result == 0);
+    State->Flags.Sf = ((Result & SignFlag) != 0);
     State->Flags.Pf = Fast486CalculateParity(Result);
 
     /* Increment/decrement EDI */
-    if (OperandSize)
+    if (AddressSize)
     {
         if (!State->Flags.Df) State->GeneralRegs[FAST486_REG_EDI].Long += DataSize;
         else State->GeneralRegs[FAST486_REG_EDI].Long -= DataSize;
@@ -5915,8 +5941,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeScas)
         || (State->PrefixFlags & FAST486_PREFIX_REPNZ))
     {
         BOOLEAN Repeat = TRUE;
-        
-        if (OperandSize)
+
+        if (AddressSize)
         {
             if ((--State->GeneralRegs[FAST486_REG_ECX].Long) == 0)
             {
@@ -5971,7 +5997,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeIns)
     if (State->PrefixFlags & FAST486_PREFIX_REP)
     {
         UCHAR Block[STRING_BLOCK_SIZE];
-        ULONG Count = OperandSize ? State->GeneralRegs[FAST486_REG_ECX].Long
+        ULONG Count = AddressSize ? State->GeneralRegs[FAST486_REG_ECX].Long
                                   : State->GeneralRegs[FAST486_REG_ECX].LowWord;
 
         /* Clear the memory block */
@@ -5997,7 +6023,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeIns)
             State->IoReadCallback(State,
                                   State->GeneralRegs[FAST486_REG_EDX].LowWord,
                                   Block,
-                                  Processed * DataSize);
+                                  Processed,
+                                  DataSize);
 
             if (State->Flags.Df)
             {
@@ -6029,7 +6056,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeIns)
                                     Processed * DataSize))
             {
                 /* Set ECX */
-                if (OperandSize) State->GeneralRegs[FAST486_REG_ECX].Long = Count;
+                if (AddressSize) State->GeneralRegs[FAST486_REG_ECX].Long = Count;
                 else State->GeneralRegs[FAST486_REG_ECX].LowWord = LOWORD(Count);
 
                 /* Exception occurred */
@@ -6048,7 +6075,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeIns)
         }
 
         /* Clear ECX */
-        if (OperandSize) State->GeneralRegs[FAST486_REG_ECX].Long = 0;
+        if (AddressSize) State->GeneralRegs[FAST486_REG_ECX].Long = 0;
         else State->GeneralRegs[FAST486_REG_ECX].LowWord = 0;
     }
     else
@@ -6059,6 +6086,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeIns)
         State->IoReadCallback(State,
                               State->GeneralRegs[FAST486_REG_EDX].LowWord,
                               &Data,
+                              1,
                               DataSize);
 
         /* Write to the destination operand */
@@ -6074,7 +6102,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeIns)
         }
 
         /* Increment/decrement EDI */
-        if (OperandSize)
+        if (AddressSize)
         {
             if (!State->Flags.Df) State->GeneralRegs[FAST486_REG_EDI].Long += DataSize;
             else State->GeneralRegs[FAST486_REG_EDI].Long -= DataSize;
@@ -6110,7 +6138,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeOuts)
     if (State->PrefixFlags & FAST486_PREFIX_REP)
     {
         UCHAR Block[STRING_BLOCK_SIZE];
-        ULONG Count = OperandSize ? State->GeneralRegs[FAST486_REG_ECX].Long
+        ULONG Count = AddressSize ? State->GeneralRegs[FAST486_REG_ECX].Long
                                   : State->GeneralRegs[FAST486_REG_ECX].LowWord;
 
         /* Clear the memory block */
@@ -6142,7 +6170,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeOuts)
                                    Processed * DataSize))
             {
                 /* Set ECX */
-                if (OperandSize) State->GeneralRegs[FAST486_REG_ECX].Long = Count;
+                if (AddressSize) State->GeneralRegs[FAST486_REG_ECX].Long = Count;
                 else State->GeneralRegs[FAST486_REG_ECX].LowWord = LOWORD(Count);
 
                 /* Exception occurred */
@@ -6174,7 +6202,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeOuts)
             State->IoWriteCallback(State,
                                    State->GeneralRegs[FAST486_REG_EDX].LowWord,
                                    Block,
-                                   Processed * DataSize);
+                                   Processed,
+                                   DataSize);
 
             if (!State->Flags.Df)
             {
@@ -6188,7 +6217,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeOuts)
         }
 
         /* Clear ECX */
-        if (OperandSize) State->GeneralRegs[FAST486_REG_ECX].Long = 0;
+        if (AddressSize) State->GeneralRegs[FAST486_REG_ECX].Long = 0;
         else State->GeneralRegs[FAST486_REG_ECX].LowWord = 0;
     }
     else
@@ -6212,10 +6241,11 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeOuts)
         State->IoWriteCallback(State,
                                State->GeneralRegs[FAST486_REG_EDX].LowWord,
                                &Data,
+                               1,
                                DataSize);
 
         /* Increment/decrement ESI */
-        if (OperandSize)
+        if (AddressSize)
         {
             if (!State->Flags.Df) State->GeneralRegs[FAST486_REG_ESI].Long += DataSize;
             else State->GeneralRegs[FAST486_REG_ESI].Long -= DataSize;
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