[TableGen][DecoderEmitter] Remove unused variables (NFC) (#153262)

Author: s-barannikov

llvm/utils/TableGen/DecoderEmitter.cpp

@@ -385,7 +385,6 @@ class Filter {
   const FilterChooser &Owner; // FilterChooser who owns this filter
   unsigned StartBit; // the starting bit position
   unsigned NumBits;  // number of bits to filter
-  bool Mixed;        // a mixed region contains both set and unset bits
 
   // Map of well-known segment value to the set of uid's with that value.
   std::map<uint64_t, std::vector<EncodingIDAndOpcode>> FilteredInstructions;
@@ -404,8 +403,7 @@ class Filter {
 
 public:
   Filter(Filter &&f);
-  Filter(const FilterChooser &owner, unsigned startBit, unsigned numBits,
-         bool mixed);
+  Filter(const FilterChooser &owner, unsigned startBit, unsigned numBits);
 
   ~Filter() = default;
 
@@ -614,7 +612,7 @@ class FilterChooser {
                                             unsigned Opc) const;
 
   // Assign a single filter and run with it.
-  void runSingleFilter(unsigned startBit, unsigned numBit, bool mixed);
+  void runSingleFilter(unsigned startBit, unsigned numBit);
 
   // reportRegion is a helper function for filterProcessor to mark a region as
   // eligible for use as a filter region.
@@ -646,15 +644,14 @@ class FilterChooser {
 ///////////////////////////
 
 Filter::Filter(Filter &&f)
-    : Owner(f.Owner), StartBit(f.StartBit), NumBits(f.NumBits), Mixed(f.Mixed),
+    : Owner(f.Owner), StartBit(f.StartBit), NumBits(f.NumBits),
       FilteredInstructions(std::move(f.FilteredInstructions)),
       VariableInstructions(std::move(f.VariableInstructions)),
       FilterChooserMap(std::move(f.FilterChooserMap)),
       NumFiltered(f.NumFiltered), LastOpcFiltered(f.LastOpcFiltered) {}
 
-Filter::Filter(const FilterChooser &owner, unsigned startBit, unsigned numBits,
-               bool mixed)
-    : Owner(owner), StartBit(startBit), NumBits(numBits), Mixed(mixed) {
+Filter::Filter(const FilterChooser &owner, unsigned startBit, unsigned numBits)
+    : Owner(owner), StartBit(startBit), NumBits(numBits) {
   assert(StartBit + NumBits - 1 < Owner.BitWidth);
 
   NumFiltered = 0;
@@ -1537,10 +1534,9 @@ void FilterChooser::emitSingletonTableEntry(DecoderTableInfo &TableInfo,
 
 // Assign a single filter and run with it.  Top level API client can initialize
 // with a single filter to start the filtering process.
-void FilterChooser::runSingleFilter(unsigned startBit, unsigned numBit,
-                                    bool mixed) {
+void FilterChooser::runSingleFilter(unsigned startBit, unsigned numBit) {
   Filters.clear();
-  Filters.emplace_back(*this, startBit, numBit, true);
+  Filters.emplace_back(*this, startBit, numBit);
   BestIndex = 0; // Sole Filter instance to choose from.
   bestFilter().recurse();
 }
@@ -1549,10 +1545,8 @@ void FilterChooser::runSingleFilter(unsigned startBit, unsigned numBit,
 // eligible for use as a filter region.
 void FilterChooser::reportRegion(bitAttr_t RA, unsigned StartBit,
                                  unsigned BitIndex, bool AllowMixed) {
-  if (RA == ATTR_MIXED && AllowMixed)
-    Filters.emplace_back(*this, StartBit, BitIndex - StartBit, true);
-  else if (RA == ATTR_ALL_SET && !AllowMixed)
-    Filters.emplace_back(*this, StartBit, BitIndex - StartBit, false);
+  if (AllowMixed ? RA == ATTR_MIXED : RA == ATTR_ALL_SET)
+    Filters.emplace_back(*this, StartBit, BitIndex - StartBit);
 }
 
 // FilterProcessor scans the well-known encoding bits of the instructions and
@@ -1583,7 +1577,7 @@ bool FilterChooser::filterProcessor(bool AllowMixed, bool Greedy) {
       // Look for islands of undecoded bits of any instruction.
       if (getIslands(Islands, Insn) > 0) {
         // Found an instruction with island(s).  Now just assign a filter.
-        runSingleFilter(Islands[0].StartBit, Islands[0].NumBits, true);
+        runSingleFilter(Islands[0].StartBit, Islands[0].NumBits);
         return true;
       }
     }