Revert "Use std::bitset for SubtargetFeatures"

This reverts commit r233055.

It still causes buildbot failures (gcc running out of memory on several platforms, and a self-host failure on arm), although less than the previous time.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233068 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/MC/MCInstPrinter.h

@@ -10,7 +10,6 @@
 #ifndef LLVM_MC_MCINSTPRINTER_H
 #define LLVM_MC_MCINSTPRINTER_H
 
-#include "llvm/MC/SubtargetFeature.h"
 #include "llvm/Support/DataTypes.h"
 #include "llvm/Support/Format.h"
 
@@ -42,7 +41,7 @@ protected:
   const MCRegisterInfo &MRI;
 
   /// The current set of available features.
-  FeatureBitset AvailableFeatures;
+  uint64_t AvailableFeatures;
 
   /// True if we are printing marked up assembly.
   bool UseMarkup;
@@ -59,7 +58,7 @@ public:
   MCInstPrinter(const MCAsmInfo &mai, const MCInstrInfo &mii,
                 const MCRegisterInfo &mri)
     : CommentStream(nullptr), MAI(mai), MII(mii), MRI(mri),
-      AvailableFeatures(), UseMarkup(0), PrintImmHex(0),
+      AvailableFeatures(0), UseMarkup(0), PrintImmHex(0),
       PrintHexStyle(HexStyle::C) {}
 
   virtual ~MCInstPrinter();
@@ -79,8 +78,8 @@ public:
   /// printRegName - Print the assembler register name.
   virtual void printRegName(raw_ostream &OS, unsigned RegNo) const;
 
-  const FeatureBitset& getAvailableFeatures() const { return AvailableFeatures; }
-  void setAvailableFeatures(const FeatureBitset& Value) { AvailableFeatures = Value; }
+  uint64_t getAvailableFeatures() const { return AvailableFeatures; }
+  void setAvailableFeatures(uint64_t Value) { AvailableFeatures = Value; }
 
   bool getUseMarkup() const { return UseMarkup; }
   void setUseMarkup(bool Value) { UseMarkup = Value; }

include/llvm/MC/MCInstrDesc.h

@@ -150,7 +150,7 @@ public:
   const uint16_t *ImplicitUses;  // Registers implicitly read by this instr
   const uint16_t *ImplicitDefs;  // Registers implicitly defined by this instr
   const MCOperandInfo *OpInfo;   // 'NumOperands' entries about operands
-  FeatureBitset   DeprecatedFeatureMask; // Feature bits that this is deprecated on, if any
+  uint64_t DeprecatedFeatureMask;// Feature bits that this is deprecated on, if any
   // A complex method to determine is a certain is deprecated or not, and return
   // the reason for deprecation.
   bool (*ComplexDeprecationInfo)(MCInst &, MCSubtargetInfo &, std::string &);
@@ -173,7 +173,7 @@ public:
                          std::string &Info) const {
     if (ComplexDeprecationInfo)
       return ComplexDeprecationInfo(MI, STI, Info);
-    if ((STI.getFeatureBits() & DeprecatedFeatureMask).any()) {
+    if ((DeprecatedFeatureMask & STI.getFeatureBits()) != 0) {
       // FIXME: it would be nice to include the subtarget feature here.
       Info = "deprecated";
       return true;

include/llvm/MC/MCSubtargetInfo.h

@@ -42,7 +42,7 @@ class MCSubtargetInfo {
   const InstrStage *Stages;            // Instruction itinerary stages
   const unsigned *OperandCycles;       // Itinerary operand cycles
   const unsigned *ForwardingPaths;     // Forwarding paths
-  FeatureBitset FeatureBits;           // Feature bits for current CPU + FS
+  uint64_t FeatureBits;                // Feature bits for current CPU + FS
 
 public:
   void InitMCSubtargetInfo(StringRef TT, StringRef CPU, StringRef FS,
@@ -67,13 +67,13 @@ public:
 
   /// getFeatureBits - Return the feature bits.
   ///
-  const FeatureBitset& getFeatureBits() const {
+  uint64_t getFeatureBits() const {
     return FeatureBits;
   }
 
   /// setFeatureBits - Set the feature bits.
   ///
-  void setFeatureBits(FeatureBitset& FeatureBits_) { FeatureBits = FeatureBits_; }
+  void setFeatureBits(uint64_t FeatureBits_) { FeatureBits = FeatureBits_; }
 
   /// InitMCProcessorInfo - Set or change the CPU (optionally supplemented with
   /// feature string). Recompute feature bits and scheduling model.
@@ -84,15 +84,11 @@ public:
 
   /// ToggleFeature - Toggle a feature and returns the re-computed feature
   /// bits. This version does not change the implied bits.
-  FeatureBitset ToggleFeature(uint64_t FB);
+  uint64_t ToggleFeature(uint64_t FB);
 
   /// ToggleFeature - Toggle a feature and returns the re-computed feature
-  /// bits. This version does not change the implied bits.
-  FeatureBitset ToggleFeature(const FeatureBitset& FB);
-
-  /// ToggleFeature - Toggle a set of features and returns the re-computed
-  /// feature bits. This version will also change all implied bits.
-  FeatureBitset ToggleFeature(StringRef FS);
+  /// bits. This version will also change all implied bits.
+  uint64_t ToggleFeature(StringRef FS);
 
   /// getSchedModelForCPU - Get the machine model of a CPU.
   ///

include/llvm/MC/SubtargetFeature.h

@@ -21,29 +21,11 @@
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/Triple.h"
 #include "llvm/Support/DataTypes.h"
-#include <bitset>
 
 namespace llvm {
   class raw_ostream;
   class StringRef;
 
-// A container class for subtarget features.
-// This is convenient because std::bitset does not have a constructor
-// with an initializer list of set bits.
-const unsigned MAX_SUBTARGET_FEATURES = 64;
-class FeatureBitset : public std::bitset<MAX_SUBTARGET_FEATURES> {
-public:
-  // Cannot inherit constructors because it's not supported by VC++..
-  FeatureBitset() : bitset() {}
-
-  FeatureBitset(const bitset<MAX_SUBTARGET_FEATURES>& B) : bitset(B) {}
-
-  FeatureBitset(std::initializer_list<unsigned> Init) : bitset() {
-    for (auto I = Init.begin() , E = Init.end(); I != E; ++I)
-      set(*I);
-  }
-};
-
 //===----------------------------------------------------------------------===//
 ///
 /// SubtargetFeatureKV - Used to provide key value pairs for feature and
@@ -52,8 +34,8 @@ public:
 struct SubtargetFeatureKV {
   const char *Key;                      // K-V key string
   const char *Desc;                     // Help descriptor
-  FeatureBitset Value;                  // K-V integer value
-  FeatureBitset Implies;                // K-V bit mask
+  uint64_t Value;                       // K-V integer value
+  uint64_t Implies;                     // K-V bit mask
 
   // Compare routine for std::lower_bound
   bool operator<(StringRef S) const {
@@ -100,11 +82,11 @@ public:
 
   /// ToggleFeature - Toggle a feature and returns the newly updated feature
   /// bits.
-  FeatureBitset ToggleFeature(FeatureBitset Bits, StringRef String,
+  uint64_t ToggleFeature(uint64_t Bits, StringRef String,
                          ArrayRef<SubtargetFeatureKV> FeatureTable);
 
   /// Get feature bits of a CPU.
-  FeatureBitset getFeatureBits(StringRef CPU,
+  uint64_t getFeatureBits(StringRef CPU,
                           ArrayRef<SubtargetFeatureKV> CPUTable,
                           ArrayRef<SubtargetFeatureKV> FeatureTable);