[FAST486]

Make the parameters to Fast486ReadModrm*Operands optional, so that
unnecessary extra reads aren't performed. This also eliminates the
need for dummy variables.

svn path=/branches/ntvdm/; revision=61055

diff --git a/lib/fast486/common.inl b/lib/fast486/common.inl
index 1297b24..cbced3a 100644 (file)
--- a/lib/fast486/common.inl
+++ b/lib/fast486/common.inl
@@ -935,51 +935,57 @@ Fast486ReadModrmByteOperands(PFAST486_STATE State,
 {
     FAST486_SEG_REGS Segment = FAST486_REG_DS;
 
-    /* Get the register value */
-    if (ModRegRm->Register & 0x04)
+    if (RegValue)
     {
-        /* AH, CH, DH, BH */
-        *RegValue = State->GeneralRegs[ModRegRm->Register & 0x03].HighByte;
-    }
-    else
-    {
-        /* AL, CL, DL, BL */
-        *RegValue = State->GeneralRegs[ModRegRm->Register & 0x03].LowByte;
-    }
-
-    if (!ModRegRm->Memory)
-    {
-        /* Get the second register value */
-        if (ModRegRm->SecondRegister & 0x04)
+        /* Get the register value */
+        if (ModRegRm->Register & 0x04)
         {
             /* AH, CH, DH, BH */
-            *RmValue = State->GeneralRegs[ModRegRm->SecondRegister & 0x03].HighByte;
+            *RegValue = State->GeneralRegs[ModRegRm->Register & 0x03].HighByte;
         }
         else
         {
             /* AL, CL, DL, BL */
-            *RmValue = State->GeneralRegs[ModRegRm->SecondRegister & 0x03].LowByte;
+            *RegValue = State->GeneralRegs[ModRegRm->Register & 0x03].LowByte;
         }
     }
-    else
+
+    if (RmValue)
     {
-        /* Check for the segment override */
-        if (State->PrefixFlags & FAST486_PREFIX_SEG)
+        if (!ModRegRm->Memory)
         {
-            /* Use the override segment instead */
-            Segment = State->SegmentOverride;
+            /* Get the second register value */
+            if (ModRegRm->SecondRegister & 0x04)
+            {
+                /* AH, CH, DH, BH */
+                *RmValue = State->GeneralRegs[ModRegRm->SecondRegister & 0x03].HighByte;
+            }
+            else
+            {
+                /* AL, CL, DL, BL */
+                *RmValue = State->GeneralRegs[ModRegRm->SecondRegister & 0x03].LowByte;
+            }
         }
-
-        /* Read memory */
-        if (!Fast486ReadMemory(State,
-                               Segment,
-                               ModRegRm->MemoryAddress,
-                               FALSE,
-                               RmValue,
-                               sizeof(UCHAR)))
+        else
         {
-            /* Exception occurred */
-            return FALSE;
+            /* Check for the segment override */
+            if (State->PrefixFlags & FAST486_PREFIX_SEG)
+            {
+                /* Use the override segment instead */
+                Segment = State->SegmentOverride;
+            }
+
+            /* Read memory */
+            if (!Fast486ReadMemory(State,
+                                   Segment,
+                                   ModRegRm->MemoryAddress,
+                                   FALSE,
+                                   RmValue,
+                                   sizeof(UCHAR)))
+            {
+                /* Exception occurred */
+                return FALSE;
+            }
         }
     }
 
@@ -995,33 +1001,39 @@ Fast486ReadModrmWordOperands(PFAST486_STATE State,
 {
     FAST486_SEG_REGS Segment = FAST486_REG_DS;
 
-    /* Get the register value */
-    *RegValue = State->GeneralRegs[ModRegRm->Register].LowWord;
-
-    if (!ModRegRm->Memory)
+    if (RegValue)
     {
-        /* Get the second register value */
-        *RmValue = State->GeneralRegs[ModRegRm->SecondRegister].LowWord;
+        /* Get the register value */
+        *RegValue = State->GeneralRegs[ModRegRm->Register].LowWord;
     }
-    else
+
+    if (RmValue)
     {
-        /* Check for the segment override */
-        if (State->PrefixFlags & FAST486_PREFIX_SEG)
+        if (!ModRegRm->Memory)
         {
-            /* Use the override segment instead */
-            Segment = State->SegmentOverride;
+            /* Get the second register value */
+            *RmValue = State->GeneralRegs[ModRegRm->SecondRegister].LowWord;
         }
-
-        /* Read memory */
-        if (!Fast486ReadMemory(State,
-                               Segment,
-                               ModRegRm->MemoryAddress,
-                               FALSE,
-                               RmValue,
-                               sizeof(USHORT)))
+        else
         {
-            /* Exception occurred */
-            return FALSE;
+            /* Check for the segment override */
+            if (State->PrefixFlags & FAST486_PREFIX_SEG)
+            {
+                /* Use the override segment instead */
+                Segment = State->SegmentOverride;
+            }
+
+            /* Read memory */
+            if (!Fast486ReadMemory(State,
+                                   Segment,
+                                   ModRegRm->MemoryAddress,
+                                   FALSE,
+                                   RmValue,
+                                   sizeof(USHORT)))
+            {
+                /* Exception occurred */
+                return FALSE;
+            }
         }
     }
 
@@ -1037,33 +1049,39 @@ Fast486ReadModrmDwordOperands(PFAST486_STATE State,
 {
     FAST486_SEG_REGS Segment = FAST486_REG_DS;
 
-    /* Get the register value */
-    *RegValue = State->GeneralRegs[ModRegRm->Register].Long;
-
-    if (!ModRegRm->Memory)
+    if (RegValue)
     {
-        /* Get the second register value */
-        *RmValue = State->GeneralRegs[ModRegRm->SecondRegister].Long;
+        /* Get the register value */
+        *RegValue = State->GeneralRegs[ModRegRm->Register].Long;
     }
-    else
+
+    if (RmValue)
     {
-        /* Check for the segment override */
-        if (State->PrefixFlags & FAST486_PREFIX_SEG)
+        if (!ModRegRm->Memory)
         {
-            /* Use the override segment instead */
-            Segment = State->SegmentOverride;
+            /* Get the second register value */
+            *RmValue = State->GeneralRegs[ModRegRm->SecondRegister].Long;
         }
-
-        /* Read memory */
-        if (!Fast486ReadMemory(State,
-                               Segment,
-                               ModRegRm->MemoryAddress,
-                               FALSE,
-                               RmValue,
-                               sizeof(ULONG)))
+        else
         {
-            /* Exception occurred */
-            return FALSE;
+            /* Check for the segment override */
+            if (State->PrefixFlags & FAST486_PREFIX_SEG)
+            {
+                /* Use the override segment instead */
+                Segment = State->SegmentOverride;
+            }
+
+            /* Read memory */
+            if (!Fast486ReadMemory(State,
+                                   Segment,
+                                   ModRegRm->MemoryAddress,
+                                   FALSE,
+                                   RmValue,
+                                   sizeof(ULONG)))
+            {
+                /* Exception occurred */
+                return FALSE;
+            }
         }
     }
 

diff --git a/lib/fast486/extraops.c b/lib/fast486/extraops.c
index d7db59c..ab7b222 100644 (file)
--- a/lib/fast486/extraops.c
+++ b/lib/fast486/extraops.c
@@ -570,10 +570,10 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBitTest)
 
     if (OperandSize)
     {
-        ULONG Dummy, Value;
+        ULONG Value;
 
         /* Read the value */
-        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -584,10 +584,10 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBitTest)
     }
     else
     {
-        USHORT Dummy, Value;
+        USHORT Value;
 
         /* Read the value */
-        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -755,10 +755,10 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBts)
 
     if (OperandSize)
     {
-        ULONG Dummy, Value;
+        ULONG Value;
 
         /* Read the value */
-        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -779,10 +779,10 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBts)
     }
     else
     {
-        USHORT Dummy, Value;
+        USHORT Value;
 
         /* Read the value */
-        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -1216,10 +1216,10 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBtr)
 
     if (OperandSize)
     {
-        ULONG Dummy, Value;
+        ULONG Value;
 
         /* Read the value */
-        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -1240,10 +1240,10 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBtr)
     }
     else
     {
-        USHORT Dummy, Value;
+        USHORT Value;
 
         /* Read the value */
-        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -1339,7 +1339,7 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeLfsLgs)
 
 FAST486_OPCODE_HANDLER(Fast486ExtOpcodeMovzxByte)
 {
-    UCHAR Dummy, Value;
+    UCHAR Value;
     BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
     FAST486_MOD_REG_RM ModRegRm;
 
@@ -1356,7 +1356,7 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeMovzxByte)
     }
 
     /* Read the operands */
-    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, &Dummy, &Value))
+    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, NULL, &Value))
     {
         /* Exception occurred */
         return FALSE;
@@ -1371,7 +1371,7 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeMovzxByte)
 
 FAST486_OPCODE_HANDLER(Fast486ExtOpcodeMovzxWord)
 {
-    USHORT Dummy, Value;
+    USHORT Value;
     BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
     FAST486_MOD_REG_RM ModRegRm;
 
@@ -1388,7 +1388,7 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeMovzxWord)
     }
 
     /* Read the operands */
-    if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Dummy, &Value))
+    if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, &Value))
     {
         /* Exception occurred */
         return FALSE;
@@ -1441,10 +1441,10 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBtc)
 
     if (OperandSize)
     {
-        ULONG Dummy, Value;
+        ULONG Value;
 
         /* Read the value */
-        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -1465,10 +1465,10 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBtc)
     }
     else
     {
-        USHORT Dummy, Value;
+        USHORT Value;
 
         /* Read the value */
-        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -1495,7 +1495,7 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBtc)
 FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBsf)
 {
     INT i;
-    ULONG Dummy = 0, Value = 0;
+    ULONG Value = 0;
     BOOLEAN OperandSize, AddressSize;
     FAST486_MOD_REG_RM ModRegRm;
     ULONG BitNumber;
@@ -1522,7 +1522,7 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBsf)
     /* Read the value */
     if (OperandSize)
     {
-        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -1532,7 +1532,7 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBsf)
     {
         if (!Fast486ReadModrmWordOperands(State,
                                           &ModRegRm,
-                                          (PUSHORT)&Dummy,
+                                          (PUSHORT)NULL,
                                           (PUSHORT)&Value))
         {
             /* Exception occurred */
@@ -1580,7 +1580,7 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBsf)
 FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBsr)
 {
     INT i;
-    ULONG Dummy = 0, Value = 0;
+    ULONG Value = 0;
     BOOLEAN OperandSize, AddressSize;
     FAST486_MOD_REG_RM ModRegRm;
     ULONG BitNumber;
@@ -1607,7 +1607,7 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBsr)
     /* Read the value */
     if (OperandSize)
     {
-        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -1617,7 +1617,7 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBsr)
     {
         if (!Fast486ReadModrmWordOperands(State,
                                           &ModRegRm,
-                                          (PUSHORT)&Dummy,
+                                          (PUSHORT)NULL,
                                           (PUSHORT)&Value))
         {
             /* Exception occurred */
@@ -1664,7 +1664,6 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeBsr)
 
 FAST486_OPCODE_HANDLER(Fast486ExtOpcodeMovsxByte)
 {
-    UCHAR Dummy;
     CHAR Value;
     BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
     FAST486_MOD_REG_RM ModRegRm;
@@ -1682,7 +1681,7 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeMovsxByte)
     }
 
     /* Read the operands */
-    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, &Dummy, (PUCHAR)&Value))
+    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, NULL, (PUCHAR)&Value))
     {
         /* Exception occurred */
         return FALSE;
@@ -1697,7 +1696,6 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeMovsxByte)
 
 FAST486_OPCODE_HANDLER(Fast486ExtOpcodeMovsxWord)
 {
-    USHORT Dummy;
     SHORT Value;
     BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
     FAST486_MOD_REG_RM ModRegRm;
@@ -1715,7 +1713,7 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeMovsxWord)
     }
 
     /* Read the operands */
-    if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Dummy, (PUSHORT)&Value))
+    if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, (PUSHORT)&Value))
     {
         /* Exception occurred */
         return FALSE;

diff --git a/lib/fast486/opcodes.c b/lib/fast486/opcodes.c
index 0268269..ac15525 100644 (file)
--- a/lib/fast486/opcodes.c
+++ b/lib/fast486/opcodes.c
@@ -3951,9 +3951,9 @@ 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;
@@ -3963,9 +3963,9 @@ 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;

diff --git a/lib/fast486/opgroups.c b/lib/fast486/opgroups.c
index 232eb25..9519aeb 100644 (file)
--- a/lib/fast486/opgroups.c
+++ b/lib/fast486/opgroups.c
@@ -293,7 +293,7 @@ Fast486RotateOperation(PFAST486_STATE State,
 
 FAST486_OPCODE_HANDLER(Fast486OpcodeGroup8082)
 {
-    UCHAR Immediate, Dummy, Value;
+    UCHAR Immediate, Value;
     FAST486_MOD_REG_RM ModRegRm;
     BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
 
@@ -313,7 +313,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup8082)
     }
 
     /* Read the operands */
-    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, &Dummy, &Value))
+    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, NULL, &Value))
     {
         /* Exception occurred */
         return FALSE;
@@ -349,7 +349,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup81)
 
     if (OperandSize)
     {
-        ULONG Immediate, Value, Dummy;
+        ULONG Immediate, Value;
 
         /* Fetch the immediate operand */
         if (!Fast486FetchDword(State, &Immediate))
@@ -359,7 +359,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup81)
         }
 
         /* Read the operands */
-        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -376,7 +376,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup81)
     }
     else
     {
-        USHORT Immediate, Value, Dummy;
+        USHORT Immediate, Value;
 
         /* Fetch the immediate operand */
         if (!Fast486FetchWord(State, &Immediate))
@@ -386,7 +386,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup81)
         }
 
         /* Read the operands */
-        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -432,10 +432,10 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup83)
     if (OperandSize)
     {
         ULONG Immediate = (ULONG)((LONG)ImmByte); // Sign extend
-        ULONG Value, Dummy;
+        ULONG Value;
 
         /* Read the operands */
-        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -453,10 +453,10 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup83)
     else
     {
         USHORT Immediate = (USHORT)((SHORT)ImmByte); // Sign extend
-        USHORT Value, Dummy;
+        USHORT Value;
 
         /* Read the operands */
-        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -527,7 +527,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup8F)
 
 FAST486_OPCODE_HANDLER(Fast486OpcodeGroupC0)
 {
-    UCHAR Dummy, Value, Count;
+    UCHAR Value, Count;
     FAST486_MOD_REG_RM ModRegRm;
     BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
 
@@ -547,7 +547,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupC0)
     }
 
     /* Read the operands */
-    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, &Dummy, &Value))
+    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, NULL, &Value))
     {
         /* Exception occurred */
         return FALSE;
@@ -593,10 +593,10 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupC1)
 
     if (OperandSize)
     {
-        ULONG Dummy, Value;
+        ULONG Value;
 
         /* Read the operands */
-        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -614,10 +614,10 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupC1)
     }
     else
     {
-        USHORT Dummy, Value;
+        USHORT Value;
 
         /* Read the operands */
-        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -728,7 +728,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupC7)
 
 FAST486_OPCODE_HANDLER(Fast486OpcodeGroupD0)
 {
-    UCHAR Dummy, Value;
+    UCHAR Value;
     FAST486_MOD_REG_RM ModRegRm;
     BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
 
@@ -741,7 +741,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupD0)
     }
 
     /* Read the operands */
-    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, &Dummy, &Value))
+    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, NULL, &Value))
     {
         /* Exception occurred */
         return FALSE;
@@ -776,10 +776,10 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupD1)
 
     if (OperandSize)
     {
-        ULONG Dummy, Value;
+        ULONG Value;
 
         /* Read the operands */
-        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -793,10 +793,10 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupD1)
     }
     else
     {
-        USHORT Dummy, Value;
+        USHORT Value;
 
         /* Read the operands */
-        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -812,7 +812,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupD1)
 
 FAST486_OPCODE_HANDLER(Fast486OpcodeGroupD2)
 {
-    UCHAR Dummy, Value;
+    UCHAR Value;
     FAST486_MOD_REG_RM ModRegRm;
     BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
 
@@ -825,7 +825,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupD2)
     }
 
     /* Read the operands */
-    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, &Dummy, &Value))
+    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, NULL, &Value))
     {
         /* Exception occurred */
         return FALSE;
@@ -863,10 +863,10 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupD3)
 
     if (OperandSize)
     {
-        ULONG Dummy, Value;
+        ULONG Value;
 
         /* Read the operands */
-        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -884,10 +884,10 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupD3)
     }
     else
     {
-        USHORT Dummy, Value;
+        USHORT Value;
 
         /* Read the operands */
-        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -907,7 +907,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupD3)
 
 FAST486_OPCODE_HANDLER(Fast486OpcodeGroupF6)
 {
-    UCHAR Dummy, Value = 0;
+    UCHAR Value = 0;
     FAST486_MOD_REG_RM ModRegRm;
     BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
 
@@ -920,7 +920,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupF6)
     }
 
     /* Read the operands */
-    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, &Dummy, &Value))
+    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, NULL, &Value))
     {
         /* Exception occurred */
         return FALSE;
@@ -1039,7 +1039,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupF6)
 
 FAST486_OPCODE_HANDLER(Fast486OpcodeGroupF7)
 {
-    ULONG Dummy, Value = 0, SignFlag;
+    ULONG Value = 0, SignFlag;
     FAST486_MOD_REG_RM ModRegRm;
     BOOLEAN OperandSize, AddressSize;
 
@@ -1062,7 +1062,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupF7)
     if (OperandSize)
     {
         /* 32-bit */
-        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -1071,7 +1071,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupF7)
     else
     {
         /* 16-bit */
-        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, (PUSHORT)&Dummy, (PUSHORT)&Value))
+        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, (PUSHORT)&Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -1284,7 +1284,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupF7)
 
 FAST486_OPCODE_HANDLER(Fast486OpcodeGroupFE)
 {
-    UCHAR Dummy, Value;
+    UCHAR Value;
     FAST486_MOD_REG_RM ModRegRm;
     BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
 
@@ -1304,7 +1304,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupFE)
     }
 
     /* Read the operands */
-    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, &Dummy, &Value))
+    if (!Fast486ReadModrmByteOperands(State, &ModRegRm, NULL, &Value))
     {
         /* Exception occurred */
         return FALSE;
@@ -1363,9 +1363,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupFF)
     /* Read the operands */
     if (OperandSize)
     {
-        ULONG Dummy, Value;
+        ULONG Value;
 
-        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -1506,9 +1506,9 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupFF)
     }
     else
     {
-        USHORT Dummy, Value;
+        USHORT Value;
 
-        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -1813,7 +1813,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup0F01)
         /* LMSW */
         case 6:
         {
-            USHORT MachineStatusWord, Dummy;
+            USHORT MachineStatusWord;
 
             /* This is a privileged instruction */
             if (Fast486GetCurrentPrivLevel(State) != 0)
@@ -1823,7 +1823,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup0F01)
             }
 
             /* Read the new Machine Status Word */
-            if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Dummy, &MachineStatusWord))
+            if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, &MachineStatusWord))
             {
                 /* Exception occurred */
                 return FALSE;
@@ -1928,10 +1928,10 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup0FBA)
 
     if (OperandSize)
     {
-        ULONG Dummy, Value;
+        ULONG Value;
 
         /* Read the value */
-        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;
@@ -1968,10 +1968,10 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup0FBA)
     }
     else
     {
-        USHORT Dummy, Value;
+        USHORT Value;
 
         /* Read the value */
-        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Dummy, &Value))
+        if (!Fast486ReadModrmWordOperands(State, &ModRegRm, NULL, &Value))
         {
             /* Exception occurred */
             return FALSE;