Return -1 only on failure to execute a program.

Also fix some comments.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109499 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 36 insertions, 27 deletions

diff --git a/include/llvm/CompilerDriver/Action.h b/include/llvm/CompilerDriver/Action.h
index 4ff6fd9..f2b7965 100644
--- a/include/llvm/CompilerDriver/Action.h
+++ b/include/llvm/CompilerDriver/Action.h
@@ -43,7 +43,7 @@ namespace llvmc {
     }
     bool IsConstructed () { return (Command_.size() != 0);}
 
-    /// Execute - Executes the represented action.
+    /// Execute - Executes the command. Returns -1 on error.
     int Execute () const;
     bool StopCompilation () const { return StopCompilation_; }
     const std::string& OutFile() { return OutFile_; }
diff --git a/include/llvm/CompilerDriver/CompilationGraph.h b/include/llvm/CompilerDriver/CompilationGraph.h
index 9f2e50e..e3b0cff 100644
--- a/include/llvm/CompilerDriver/CompilationGraph.h
+++ b/include/llvm/CompilerDriver/CompilationGraph.h
@@ -132,28 +132,28 @@ namespace llvmc {
     void insertNode(Tool* T);
 
     /// insertEdge - Insert a new edge into the graph. Takes ownership
-    /// of the Edge object.
+    /// of the Edge object. Returns non-zero value on error.
     int insertEdge(const std::string& A, Edge* E);
 
-    /// Build - Build target(s) from the input file set. Command-line
-    /// options are passed implicitly as global variables.
+    /// Build - Build target(s) from the input file set. Command-line options
+    /// are passed implicitly as global variables. Returns non-zero value on
+    /// error (usually the failed program's exit code).
     int Build(llvm::sys::Path const& TempDir, const LanguageMap& LangMap);
 
-    /// Check - Check the compilation graph for common errors like
-    /// cycles, input/output language mismatch and multiple default
-    /// edges. Prints error messages and in case it finds any errors.
+    /// Check - Check the compilation graph for common errors like cycles,
+    /// input/output language mismatch and multiple default edges. Prints error
+    /// messages and in case it finds any errors.
     int Check();
 
-    /// getNode - Return a reference to the node correponding to the
-    /// given tool name. Throws std::runtime_error.
+    /// getNode - Return a reference to the node corresponding to the given tool
+    /// name. Returns 0 on error.
     Node* getNode(const std::string& ToolName);
     const Node* getNode(const std::string& ToolName) const;
 
-    /// viewGraph - This function is meant for use from the debugger.
-    /// You can just say 'call G->viewGraph()' and a ghostview window
-    /// should pop up from the program, displaying the compilation
-    /// graph. This depends on there being a 'dot' and 'gv' program
-    /// in your path.
+    /// viewGraph - This function is meant for use from the debugger. You can
+    /// just say 'call G->viewGraph()' and a ghostview window should pop up from
+    /// the program, displaying the compilation graph. This depends on there
+    /// being a 'dot' and 'gv' program in your path.
     void viewGraph();
 
     /// writeGraph - Write Graphviz .dot source file to the current direcotry.
@@ -167,12 +167,11 @@ namespace llvmc {
     // Helper functions.
 
     /// getToolsVector - Return a reference to the list of tool names
-    /// corresponding to the given language name. Throws
-    /// std::runtime_error.
+    /// corresponding to the given language name. Returns 0 on error.
     const tools_vector_type* getToolsVector(const std::string& LangName) const;
 
-    /// PassThroughGraph - Pass the input file through the toolchain
-    /// starting at StartNode.
+    /// PassThroughGraph - Pass the input file through the toolchain starting at
+    /// StartNode.
     int PassThroughGraph (const llvm::sys::Path& In, const Node* StartNode,
                           const InputLanguagesSet& InLangs,
                           const llvm::sys::Path& TempDir,
@@ -185,26 +184,32 @@ namespace llvmc {
                               InputLanguagesSet& InLangs,
                               const LanguageMap& LangMap) const;
 
-    /// BuildInitial - Traverse the initial parts of the toolchains.
+    /// BuildInitial - Traverse the initial parts of the toolchains. Returns
+    /// non-zero value on error.
     int BuildInitial(InputLanguagesSet& InLangs,
                      const llvm::sys::Path& TempDir,
                      const LanguageMap& LangMap);
 
-    /// TopologicalSort - Sort the nodes in topological order.
+    /// TopologicalSort - Sort the nodes in topological order. Returns non-zero
+    /// value on error.
     int TopologicalSort(std::vector<const Node*>& Out);
-    /// TopologicalSortFilterJoinNodes - Call TopologicalSort and
-    /// filter the resulting list to include only Join nodes.
+    /// TopologicalSortFilterJoinNodes - Call TopologicalSort and filter the
+    /// resulting list to include only Join nodes. Returns non-zero value on
+    /// error.
     int TopologicalSortFilterJoinNodes(std::vector<const Node*>& Out);
 
     // Functions used to implement Check().
 
-    /// CheckLanguageNames - Check that output/input language names
-    /// match for all nodes.
+    /// CheckLanguageNames - Check that output/input language names match for
+    /// all nodes. Returns non-zero value on error (number of errors
+    /// encountered).
     int CheckLanguageNames() const;
-    /// CheckMultipleDefaultEdges - check that there are no multiple
-    /// default default edges.
+    /// CheckMultipleDefaultEdges - check that there are no multiple default
+    /// default edges. Returns non-zero value on error (number of errors
+    /// encountered).
     int CheckMultipleDefaultEdges() const;
-    /// CheckCycles - Check that there are no cycles in the graph.
+    /// CheckCycles - Check that there are no cycles in the graph. Returns
+    /// non-zero value on error (number of errors encountered).
     int CheckCycles();
 
   };
diff --git a/include/llvm/CompilerDriver/Tool.h b/include/llvm/CompilerDriver/Tool.h
index d064a03..45ef50d 100644
--- a/include/llvm/CompilerDriver/Tool.h
+++ b/include/llvm/CompilerDriver/Tool.h
@@ -38,6 +38,8 @@ namespace llvmc {
 
     virtual ~Tool() {}
 
+    /// GenerateAction - Generate an Action given particular command-line
+    /// options. Returns non-zero value on error.
     virtual int GenerateAction (Action& Out,
                                 const PathVector& inFiles,
                                 const bool HasChildren,
@@ -45,6 +47,8 @@ namespace llvmc {
                                 const InputLanguagesSet& InLangs,
                                 const LanguageMap& LangMap) const = 0;
 
+    /// GenerateAction - Generate an Action given particular command-line
+    /// options. Returns non-zero value on error.
     virtual int GenerateAction (Action& Out,
                                 const llvm::sys::Path& inFile,
                                 const bool HasChildren,