Subzero: Fix off-by-one asserts in intrinsic info lookup routines.

src/IceIntrinsics.h

 //===- subzero/src/IceIntrinsics.h - List of Ice Intrinsics -----*- C++ -*-===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 122 matching lines @@
     uint8_t NumTypes;
 
     /// Validates that type signature of call matches intrinsic.
     /// If WrongArgumentType is returned, ArgIndex is set to corresponding
     /// argument index.
     ValidateCallValue validateCall(const Ice::InstCall *Call,
                                    SizeT &ArgIndex) const;
 
     /// Returns the return type of the intrinsic.
     Type getReturnType() const {
-      assert(NumTypes > 1);
+      assert(NumTypes > 0);
       return Signature[0];
     }
 
     /// Returns number of arguments expected.
     SizeT getNumArgs() const {
-      assert(NumTypes > 1);
+      assert(NumTypes > 0);
       return NumTypes - 1;
     }
 
     /// Returns type of Index-th argument.
     Type getArgType(SizeT Index) const;
   };
 
   /// Find the information about a given intrinsic, based on function name.  If
   /// the function name does not have the common "llvm." prefix, nullptr is
   /// returned and Error is set to false.  Otherwise, tries to find a reference
   /// to a FullIntrinsicInfo entry (valid for the lifetime of the map).  If
   /// found, sets Error to false and returns the reference.  If not found, sets
   /// Error to true and returns nullptr (indicating an unknown "llvm.foo"
   /// intrinsic).
   const FullIntrinsicInfo *find(const IceString &Name, bool &Error) const;
 
 private:
   // TODO(jvoung): May want to switch to something like LLVM's StringMap.
   using IntrinsicMap = std::map<IceString, FullIntrinsicInfo>;
   IntrinsicMap Map;
 };
 
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICEINTRINSICS_H