Subzero: Fix floating-point constant pooling.

src/IceGlobalContext.cpp

Index: src/IceGlobalContext.cpp
diff --git a/src/IceGlobalContext.cpp b/src/IceGlobalContext.cpp
index 6badc559aa9236b017ad9ad262d216812c0e25d4..76f9211ae22ae82378d35c3c7e97cb46d21e6a8b 100644
--- a/src/IceGlobalContext.cpp
+++ b/src/IceGlobalContext.cpp
@@ -65,7 +65,15 @@ public:
   }
 
 private:
-  typedef std::unordered_map<KeyType, ValueType *> ContainerType;
+  struct compare {
+    bool operator()(const KeyType &Value1, const KeyType &Value2) const {
+      if (std::is_floating_point<KeyType>::value)
+        return !memcmp(&Value1, &Value2, sizeof(KeyType));
+      return std::equal_to<KeyType>()(Value1, Value2);
+    }
+  };
+  typedef std::unordered_map<KeyType, ValueType *, std::hash<KeyType>, compare>
+      ContainerType;

[JF, 2015/03/19 16:33:09]

template<typename T>
struct Compare {
  typename std::enable_if<std::is_integral<T>::value, bool>::type
  operator()(const KeyType &LHS, const KeyType &RHS) const {
    return LHS == RHS;
  }
  typename std::enable_if<std::is_floating_point<T>::value, bool>::type
  operator()(const KeyType &LHS, const KeyType &RHS) const {
    return !memcmp(&RHS, &LHS, sizeof(KeyType));
  }
};
typedef std::unordered_map<KeyType, ValueType *, std::hash<KeyType>,
Compare<KeyType>>
       ContainerType;

[Jim Stichnoth, 2015/03/19 18:07:04]

Cool.  I did it a slightly different way.

It has to handle the RelocatableTuple type as well (which already has a valid ==
operator).  Is there any way to combine that with the is_integral<T> test?

[Jim Stichnoth, 2015/03/19 19:57:49]

Tweaked once more to combine integral types and RelocatableTuple.

   ContainerType Pool;
   uint32_t NextPoolID;
 };