Change behavior of calling bitcasted alias functions.

It will now only convert the arguments / return value and call
the underlying function if the types are able to be bitcasted.
This avoids using fp<->int conversions that would occur before.

llvm-svn: 187444

1 files changed, 12 insertions, 6 deletions

diff --git a/llvm/include/llvm/IR/InstrTypes.h b/llvm/include/llvm/IR/InstrTypes.h
index f50c28a5fc2..e12bb03a403 100644
--- a/llvm/include/llvm/IR/InstrTypes.h
+++ b/llvm/include/llvm/IR/InstrTypes.h
@@ -531,6 +531,12 @@ public:
     Type *DestTy ///< The Type to which the value should be cast.
   );
 
+  /// @brief Check whether a bitcast between these types is valid
+  static bool isBitCastable(
+    Type *SrcTy, ///< The Type from which the value should be cast.
+    Type *DestTy ///< The Type to which the value should be cast.
+  );
+
   /// Returns the opcode necessary to cast Val into Ty using usual casting
   /// rules.
   /// @brief Infer the opcode for cast operand and type
@@ -698,7 +704,7 @@ public:
   /// @brief Create a CmpInst
   static CmpInst *Create(OtherOps Op, unsigned short predicate, Value *S1,
                          Value *S2, const Twine &Name, BasicBlock *InsertAtEnd);
-  
+
   /// @brief Get the opcode casted to the right type
   OtherOps getOpcode() const {
     return static_cast<OtherOps>(Instruction::getOpcode());
@@ -715,15 +721,15 @@ public:
   static bool isFPPredicate(Predicate P) {
     return P >= FIRST_FCMP_PREDICATE && P <= LAST_FCMP_PREDICATE;
   }
-  
+
   static bool isIntPredicate(Predicate P) {
     return P >= FIRST_ICMP_PREDICATE && P <= LAST_ICMP_PREDICATE;
   }
-  
+
   bool isFPPredicate() const { return isFPPredicate(getPredicate()); }
   bool isIntPredicate() const { return isIntPredicate(getPredicate()); }
-  
-  
+
+
   /// For example, EQ -> NE, UGT -> ULE, SLT -> SGE,
   ///              OEQ -> UNE, UGT -> OLE, OLT -> UGE, etc.
   /// @returns the inverse predicate for the instruction's current predicate.
@@ -821,7 +827,7 @@ public:
   static inline bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
-  
+
   /// @brief Create a result type for fcmp/icmp
   static Type* makeCmpResultType(Type* opnd_type) {
     if (VectorType* vt = dyn_cast<VectorType>(opnd_type)) {