Add some happy helper methods.

llvm-svn: 26046

llvm/include/llvm/CodeGen/ValueTypes.h

@@ -17,6 +17,7 @@
 #define LLVM_CODEGEN_VALUETYPES_H
 
 #include <cassert>
+#include "llvm/Support/DataTypes.h"
 
 namespace llvm {
   class Type;
@@ -108,6 +109,19 @@ namespace MVT {  // MVT = Machine Value Types
     }
   }
   
+  /// getIntVTBitMask - Return an integer with 1's every place there are bits
+  /// in the specified integer value type.
+  static inline uint64_t getIntVTBitMask(ValueType VT) {
+    assert(isInteger(VT) && !isVector(VT) && "Only applies to int scalars!");
+    return ~0ULL >> (64-getSizeInBits(VT));
+  }
+  /// getIntVTSignBit - Return an integer with a 1 in the position of the sign
+  /// bit for the specified integer value type.
+  static inline uint64_t getIntVTSignBit(ValueType VT) {
+    assert(isInteger(VT) && !isVector(VT) && "Only applies to int scalars!");
+    return 1ULL << (getSizeInBits(VT)-1);
+  }
+
   /// MVT::getValueTypeString - This function returns value type as a string,
   /// e.g. "i32".
   const char *getValueTypeString(ValueType VT);