[BatchMode] Add CommandOutput::addOutputs and hasSameAdditionalOutputTypes.

Author: graydon

include/swift/Driver/Job.h

@@ -147,6 +147,15 @@ class CommandOutput {
   /// with the provided \p Input pair of Base and Primary inputs.
   void addPrimaryOutput(CommandInputPair Input, StringRef PrimaryOutputFile);
 
+  /// Return true iff the set of additional output types in \c this is
+  /// identical to the set of additional output types in \p other.
+  bool hasSameAdditionalOutputTypes(CommandOutput const &other) const;
+
+  /// Copy all the input pairs from \p other to \c this. Assumes (and asserts)
+  /// that \p other shares output file map and PrimaryOutputType with \c this
+  /// already, as well as AdditionalOutputTypes if \c this has any.
+  void addOutputs(CommandOutput const &other);
+
   /// Assuming (and asserting) that there is only one input pair, return the
   /// primary output file associated with it. Note that the returned StringRef
   /// may be invalidated by subsequent mutations to the \c CommandOutput.

lib/Driver/Job.cpp

@@ -52,6 +52,32 @@ void CommandOutput::ensureEntry(StringRef PrimaryInputFile,
   }
 }
 
+bool CommandOutput::hasSameAdditionalOutputTypes(
+    CommandOutput const &other) const {
+  bool sameAdditionalOutputTypes = true;
+  types::forAllTypes([&](types::ID Type) {
+      bool a = AdditionalOutputTypes.count(Type) == 0;
+      bool b = other.AdditionalOutputTypes.count(Type) == 0;
+      if (a != b)
+        sameAdditionalOutputTypes = false;
+    });
+  return sameAdditionalOutputTypes;
+}
+
+void CommandOutput::addOutputs(CommandOutput const &other) {
+  assert(PrimaryOutputType == other.PrimaryOutputType);
+  assert(&DerivedOutputMap == &other.DerivedOutputMap);
+  Inputs.append(other.Inputs.begin(),
+                other.Inputs.end());
+  // Should only be called with an empty AdditionalOutputTypes
+  // or one populated with the same types as other.
+  if (AdditionalOutputTypes.empty()) {
+    AdditionalOutputTypes = other.AdditionalOutputTypes;
+  } else {
+    assert(hasSameAdditionalOutputTypes(other));
+  }
+}
+
 CommandOutput::CommandOutput(types::ID PrimaryOutputType,
                              OutputFileMap &Derived)
     : PrimaryOutputType(PrimaryOutputType), DerivedOutputMap(Derived) {}