LLVMContext: Store APInt/APFloat directly into the ConstantInt/FP DenseMaps.

Required some APInt massaging to get proper empty/tombstone values. Apart
from making the code a bit simpler this also reduces the bucket size of
the ConstantInt map from 32 to 24 bytes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223478 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/ADT/APInt.h

@@ -91,6 +91,8 @@ class APInt {
     APINT_WORD_SIZE = static_cast<unsigned int>(sizeof(uint64_t))
   };
 
+  friend struct DenseMapAPIntKeyInfo;
+
   /// \brief Fast internal constructor
   ///
   /// This constructor is used only internally for speed of construction of
@@ -277,7 +279,6 @@ public:
   /// Simply makes *this a copy of that.
   /// @brief Copy Constructor.
   APInt(const APInt &that) : BitWidth(that.BitWidth), VAL(0) {
-    assert(BitWidth && "bitwidth too small");
     if (isSingleWord())
       VAL = that.VAL;
     else

lib/IR/Constants.cpp

@@ -555,18 +555,17 @@ Constant *ConstantInt::getFalse(Type *Ty) {
 }
 
 
-// Get a ConstantInt from an APInt. Note that the value stored in the DenseMap 
+// Get a ConstantInt from an APInt.
-// as the key, is a DenseMapAPIntKeyInfo::KeyTy which has provided the
-// operator== and operator!= to ensure that the DenseMap doesn't attempt to
-// compare APInt's of different widths, which would violate an APInt class
-// invariant which generates an assertion.
 ConstantInt *ConstantInt::get(LLVMContext &Context, const APInt &V) {
-  // Get the corresponding integer type for the bit width of the value.
-  IntegerType *ITy = IntegerType::get(Context, V.getBitWidth());
   // get an existing value or the insertion position
   LLVMContextImpl *pImpl = Context.pImpl;
-  ConstantInt *&Slot = pImpl->IntConstants[DenseMapAPIntKeyInfo::KeyTy(V, ITy)];
+  ConstantInt *&Slot = pImpl->IntConstants[V];
-  if (!Slot) Slot = new ConstantInt(ITy, V);
+  if (!Slot) {
+    // Get the corresponding integer type for the bit width of the value.
+    IntegerType *ITy = IntegerType::get(Context, V.getBitWidth());
+    Slot = new ConstantInt(ITy, V);
+  }
+  assert(Slot->getType() == IntegerType::get(Context, V.getBitWidth()));
   return Slot;
 }
 
@@ -689,7 +688,7 @@ Constant *ConstantFP::getZeroValueForNegation(Type *Ty) {
 ConstantFP* ConstantFP::get(LLVMContext &Context, const APFloat& V) {
   LLVMContextImpl* pImpl = Context.pImpl;
 
-  ConstantFP *&Slot = pImpl->FPConstants[DenseMapAPFloatKeyInfo::KeyTy(V)];
+  ConstantFP *&Slot = pImpl->FPConstants[V];
 
   if (!Slot) {
     Type *Ty;

lib/IR/LLVMContextImpl.h

@@ -46,55 +46,26 @@ class Type;
 class Value;
 
 struct DenseMapAPIntKeyInfo {
-  struct KeyTy {
+  static inline APInt getEmptyKey() { return APInt(nullptr, 0); }
-    APInt val;
+  static inline APInt getTombstoneKey() {
-    Type* type;
+    return APInt(reinterpret_cast<uint64_t *>(sizeof(uint64_t)), 0);
-    KeyTy(const APInt& V, Type* Ty) : val(V), type(Ty) {}
-    bool operator==(const KeyTy& that) const {
-      return type == that.type && this->val == that.val;
   }
-    bool operator!=(const KeyTy& that) const {
+  static unsigned getHashValue(const APInt &Key) {
-      return !this->operator==(that);
-    }
-    friend hash_code hash_value(const KeyTy &Key) {
-      return hash_combine(Key.type, Key.val);
-    }
-  };
-  static inline KeyTy getEmptyKey() { return KeyTy(APInt(1,0), nullptr); }
-  static inline KeyTy getTombstoneKey() { return KeyTy(APInt(1,1), nullptr); }
-  static unsigned getHashValue(const KeyTy &Key) {
     return static_cast<unsigned>(hash_value(Key));
   }
-  static bool isEqual(const KeyTy &LHS, const KeyTy &RHS) {
+  static bool isEqual(const APInt &LHS, const APInt &RHS) {
-    return LHS == RHS;
+    return LHS.getBitWidth() == RHS.getBitWidth() && LHS == RHS;
   }
 };
 
 struct DenseMapAPFloatKeyInfo {
-  struct KeyTy {
+  static inline APFloat getEmptyKey() { return APFloat(APFloat::Bogus, 1); }
-    APFloat val;
+  static inline APFloat getTombstoneKey() { return APFloat(APFloat::Bogus, 2); }
-    KeyTy(const APFloat& V) : val(V){}
+  static unsigned getHashValue(const APFloat &Key) {
-    bool operator==(const KeyTy& that) const {
-      return this->val.bitwiseIsEqual(that.val);
-    }
-    bool operator!=(const KeyTy& that) const {
-      return !this->operator==(that);
-    }
-    friend hash_code hash_value(const KeyTy &Key) {
-      return hash_combine(Key.val);
-    }
-  };
-  static inline KeyTy getEmptyKey() { 
-    return KeyTy(APFloat(APFloat::Bogus,1));
-  }
-  static inline KeyTy getTombstoneKey() { 
-    return KeyTy(APFloat(APFloat::Bogus,2)); 
-  }
-  static unsigned getHashValue(const KeyTy &Key) {
     return static_cast<unsigned>(hash_value(Key));
   }
-  static bool isEqual(const KeyTy &LHS, const KeyTy &RHS) {
+  static bool isEqual(const APFloat &LHS, const APFloat &RHS) {
-    return LHS == RHS;
+    return LHS.bitwiseIsEqual(RHS);
   }
 };
 
@@ -277,12 +248,10 @@ public:
   LLVMContext::YieldCallbackTy YieldCallback;
   void *YieldOpaqueHandle;
 
-  typedef DenseMap<DenseMapAPIntKeyInfo::KeyTy, ConstantInt *,
+  typedef DenseMap<APInt, ConstantInt *, DenseMapAPIntKeyInfo> IntMapTy;
-                   DenseMapAPIntKeyInfo> IntMapTy;
   IntMapTy IntConstants;
 
-  typedef DenseMap<DenseMapAPFloatKeyInfo::KeyTy, ConstantFP*, 
+  typedef DenseMap<APFloat, ConstantFP *, DenseMapAPFloatKeyInfo> FPMapTy;
-                         DenseMapAPFloatKeyInfo> FPMapTy;
   FPMapTy FPConstants;
 
   FoldingSet<AttributeImpl> AttrsSet;