Replace size method call of containers to empty method where appropriate

This patch was generated by a clang tidy checker that is being open sourced.
The documentation of that checker is the following:

/// The emptiness of a container should be checked using the empty method
/// instead of the size method. It is not guaranteed that size is a
/// constant-time function, and it is generally more efficient and also shows
/// clearer intent to use empty. Furthermore some containers may implement the
/// empty method but not implement the size method. Using empty whenever
/// possible makes it easier to switch to another container in the future.

Patch by Gábor Horváth!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226161 91177308-0d34-0410-b5e6-96231b3b80d8

utils/TableGen/CodeEmitterGen.cpp

@@ -96,7 +96,7 @@ AddCodeToMergeInOperand(Record *R, BitsInit *BI, const std::string &VarName,
     /// generated emitter, skip it.
     while (NumberedOp < NumberOps &&
            (CGI.Operands.isFlatOperandNotEmitted(NumberedOp) ||
-              (NamedOpIndices.size() && NamedOpIndices.count(
+              (!NamedOpIndices.empty() && NamedOpIndices.count(
                 CGI.Operands.getSubOperandNumber(NumberedOp).first)))) {
       ++NumberedOp;