Add an emplace(...) method to llvm::Optional<T>.

[oota-llvm.git] / include / llvm / ADT / PointerUnion.h

diff --git a/include/llvm/ADT/PointerUnion.h b/include/llvm/ADT/PointerUnion.h
index b63ee52cdddace12562164374b39a7fac9feb96d..a6dddd277621806a12cac918a0d86ce3f0abcf84 100644 (file)
--- a/include/llvm/ADT/PointerUnion.h
+++ b/include/llvm/ADT/PointerUnion.h
@@ -15,7 +15,9 @@
 #ifndef LLVM_ADT_POINTERUNION_H
 #define LLVM_ADT_POINTERUNION_H
 
+#include "llvm/ADT/DenseMapInfo.h"
 #include "llvm/ADT/PointerIntPair.h"
+#include "llvm/Support/Compiler.h"
 
 namespace llvm {
 
@@ -71,7 +73,7 @@ namespace llvm {
   ///    printf("%d %d", P.is<int*>(), P.is<float*>());  // prints "1 0"
   ///    X = P.get<int*>();     // ok.
   ///    Y = P.get<float*>();   // runtime assertion failure.
-  ///    Z = P.get<double*>();  // runtime assertion failure (regardless of tag)
+  ///    Z = P.get<double*>();  // compile time failure.
   ///    P = (float*)0;
   ///    Y = P.get<float*>();   // ok.
   ///    X = P.get<int*>();     // runtime assertion failure.
@@ -152,6 +154,12 @@ namespace llvm {
          "Can't get the address because PointerLikeTypeTraits changes the ptr");
       return (PT1 *)Val.getAddrOfPointer();
     }
+
+    /// \brief Assignment from nullptr which just clears the union.
+    const PointerUnion &operator=(std::nullptr_t) {
+      Val.initWithPointer(nullptr);
+      return *this;
+    }
     
     /// Assignment operators - Allow assigning into this union from either
     /// pointer type, setting the discriminator to remember what it came from.
@@ -176,10 +184,17 @@ namespace llvm {
   };
 
   template<typename PT1, typename PT2>
-  bool operator==(PointerUnion<PT1, PT2> lhs, PointerUnion<PT1, PT2> rhs) {
+  static bool operator==(PointerUnion<PT1, PT2> lhs,
+                         PointerUnion<PT1, PT2> rhs) {
     return lhs.getOpaqueValue() == rhs.getOpaqueValue();
   }
-  
+
+  template<typename PT1, typename PT2>
+  static bool operator!=(PointerUnion<PT1, PT2> lhs,
+                         PointerUnion<PT1, PT2> rhs) {
+    return lhs.getOpaqueValue() != rhs.getOpaqueValue();
+  }
+
   // Teach SmallPtrSet that PointerUnion is "basically a pointer", that has
   // # low bits available = min(PT1bits,PT2bits)-1.
   template<typename PT1, typename PT2>
@@ -289,6 +304,12 @@ namespace llvm {
       if (is<T>()) return get<T>();
       return T();
     }
+
+    /// \brief Assignment from nullptr which just clears the union.
+    const PointerUnion3 &operator=(std::nullptr_t) {
+      Val = nullptr;
+      return *this;
+    }
     
     /// Assignment operators - Allow assigning into this union from either
     /// pointer type, setting the discriminator to remember what it came from.
@@ -398,6 +419,12 @@ namespace llvm {
       if (is<T>()) return get<T>();
       return T();
     }
+
+    /// \brief Assignment from nullptr which just clears the union.
+    const PointerUnion4 &operator=(std::nullptr_t) {
+      Val = nullptr;
+      return *this;
+    }
     
     /// Assignment operators - Allow assigning into this union from either
     /// pointer type, setting the discriminator to remember what it came from.
@@ -447,6 +474,33 @@ namespace llvm {
           ::NumLowBitsAvailable
     };
   };
+
+  // Teach DenseMap how to use PointerUnions as keys.
+  template<typename T, typename U>
+  struct DenseMapInfo<PointerUnion<T, U> > {
+    typedef PointerUnion<T, U> Pair;
+    typedef DenseMapInfo<T> FirstInfo;
+    typedef DenseMapInfo<U> SecondInfo;
+
+    static inline Pair getEmptyKey() {
+      return Pair(FirstInfo::getEmptyKey());
+    }
+    static inline Pair getTombstoneKey() {
+      return Pair(FirstInfo::getTombstoneKey());
+    }
+    static unsigned getHashValue(const Pair &PairVal) {
+      intptr_t key = (intptr_t)PairVal.getOpaqueValue();
+      return DenseMapInfo<intptr_t>::getHashValue(key);
+    }
+    static bool isEqual(const Pair &LHS, const Pair &RHS) {
+      return LHS.template is<T>() == RHS.template is<T>() &&
+             (LHS.template is<T>() ?
+              FirstInfo::isEqual(LHS.template get<T>(),
+                                 RHS.template get<T>()) :
+              SecondInfo::isEqual(LHS.template get<U>(),
+                                  RHS.template get<U>()));
+    }
+  };
 }
 
 #endif