Revised per review feedback from previous patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41353 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/ADT/APFloat.h

@@ -194,6 +194,11 @@ namespace llvm {
     /* Bitwise comparison for equality (QNaNs compare equal, 0!=-0). */
     bool operator==(const APFloat &) const;
 
+    /* Inversion of the preceding. */
+    inline bool operator!=(const APFloat &RHS) const { 
+      return !((*this)==RHS); 
+    }
+
     /* Simple queries.  */
     fltCategory getCategory() const { return category; }
     const fltSemantics &getSemantics() const { return *semantics; }

lib/Support/APFloat.cpp

@@ -14,6 +14,7 @@
 
 #include <cassert>
 #include "llvm/ADT/APFloat.h"
+#include "llvm/Support/MathExtras.h"
 
 using namespace llvm;
 
@@ -1534,10 +1535,6 @@ APFloat::getHashValue() const {
 
 double
 APFloat::convertToDouble() const {
-  union { 
-    double d;
-    uint64_t i;
-  } u;
   assert(semantics == (const llvm::fltSemantics* const)&IEEEdouble);
   assert (partCount()==1);
 
@@ -1562,17 +1559,12 @@ APFloat::convertToDouble() const {
   } else
     assert(0);
 
-  u.i = ((mysign & 1) << 63) | ((myexponent & 0x7ff) <<  52) | 
-        (mysignificand & 0xfffffffffffffLL);
-  return u.d;
+  return BitsToDouble(((mysign & 1) << 63) | ((myexponent & 0x7ff) <<  52) | 
+        (mysignificand & 0xfffffffffffffLL));
 }
 
 float
 APFloat::convertToFloat() const {
-  union { 
-    float f;
-    int32_t i;
-  } u;
   assert(semantics == (const llvm::fltSemantics* const)&IEEEsingle);
   assert (partCount()==1);
 
@@ -1597,26 +1589,19 @@ APFloat::convertToFloat() const {
   } else
     assert(0);
 
-  u.i = ((mysign&1) << 31) | ((myexponent&0xff) << 23) | 
-        ((mysignificand & 0x7fffff));
-  return u.f;
+  return BitsToFloat(((mysign&1) << 31) | ((myexponent&0xff) << 23) | 
+        (mysignificand & 0x7fffff));
 }
 
 APFloat::APFloat(double d) {
+  uint64_t i = DoubleToBits(d);
+  uint64_t mysign = i >> 63;
+  uint64_t myexponent = (i >> 52) & 0x7ff;
+  uint64_t mysignificand = i & 0xfffffffffffffLL;
+
   initialize(&APFloat::IEEEdouble);
-  union { 
-    double d; 
-    uint64_t i;
-  } u;
-  u.d = d;
   assert(partCount()==1);
 
-  uint64_t mysign, myexponent, mysignificand;
-
-  mysign = u.i >> 63;
-  myexponent = (u.i >> 52) & 0x7ff;
-  mysignificand = u.i & 0xfffffffffffffLL;
-
   if (myexponent==0 && mysignificand==0) {
     // exponent, significand meaningless
     category = fcZero;
@@ -1637,20 +1622,14 @@ APFloat::APFloat(double d) {
 }
 
 APFloat::APFloat(float f) {
+  uint32_t i = FloatToBits(f);
+  uint32_t mysign = i >> 31;
+  uint32_t myexponent = (i >> 23) & 0xff;
+  uint32_t mysignificand = i & 0x7fffff;
+
   initialize(&APFloat::IEEEsingle);
-  union { 
-    float f;
-    uint32_t i;
-  } u;
-  u.f = f;
   assert(partCount()==1);
 
-  uint32_t mysign, myexponent, mysignificand;
-
-  mysign = u.i >> 31;
-  myexponent = (u.i >> 23) & 0xff;
-  mysignificand = u.i & 0x7fffff;
-
   if (myexponent==0 && mysignificand==0) {
     // exponent, significand meaningless
     category = fcZero;

lib/VMCore/Constants.cpp

@@ -253,25 +253,14 @@ bool ConstantFP::isExactlyValue(double V) const {
 
 namespace {
   struct DenseMapAPFloatKeyInfo {
-    struct KeyTy {
-      APFloat val;
-      KeyTy(const APFloat& V) : val(V){}
-      KeyTy(const KeyTy& that) : val(that.val) {}
-      bool operator==(const KeyTy& that) const {
-        return this->val == that.val;
-      }
-      bool operator!=(const KeyTy& that) const {
-        return !this->operator==(that);
-      }
-    };
-    static inline KeyTy getEmptyKey() { 
-      return KeyTy(APFloat(APFloat::Bogus,1));
+    static inline APFloat getEmptyKey() { 
+      return APFloat(APFloat::Bogus,1);
     }
-    static inline KeyTy getTombstoneKey() { 
-      return KeyTy(APFloat(APFloat::Bogus,2)); 
+    static inline APFloat getTombstoneKey() { 
+      return APFloat(APFloat::Bogus,2); 
     }
-    static unsigned getHashValue(const KeyTy &Key) {
-      return Key.val.getHashValue();
+    static unsigned getHashValue(const APFloat &Key) {
+      return Key.getHashValue();
     }
     static bool isPod() { return false; }
   };
@@ -279,21 +268,21 @@ namespace {
 
 //---- ConstantFP::get() implementation...
 //
-typedef DenseMap<DenseMapAPFloatKeyInfo::KeyTy, ConstantFP*, 
+typedef DenseMap<APFloat, ConstantFP*, 
                  DenseMapAPFloatKeyInfo> FPMapTy;
 
 static ManagedStatic<FPMapTy> FPConstants;
 
 ConstantFP *ConstantFP::get(const Type *Ty, double V) {
   if (Ty == Type::FloatTy) {
-    DenseMapAPFloatKeyInfo::KeyTy Key(APFloat((float)V));
+    APFloat Key(APFloat((float)V));
     ConstantFP *&Slot = (*FPConstants)[Key];
     if (Slot) return Slot;
     return Slot = new ConstantFP(Ty, (float)V);
   } else if (Ty == Type::DoubleTy) {
     // Without the redundant cast, the following is taken to be
     // a function declaration.  What a language.
-    DenseMapAPFloatKeyInfo::KeyTy Key(APFloat((double)V));
+    APFloat Key(APFloat((double)V));
     ConstantFP *&Slot = (*FPConstants)[Key];
     if (Slot) return Slot;
     return Slot = new ConstantFP(Ty, V);