Backend support for top-level Clang epxressions

This patch adds a new ExecutionPolicy, eExecutionPolicyTopLevel, which
tells the expression parser that the expression should be JITted as top
level code but nothing (except static initializers) should be run.  I
have modified the Clang expression parser to recognize this execution
policy.  On top of the existing patches that support storing IR and
maintaining a map of arbitrary Decls, this is mainly just patching up a
few places in the expression parser.

I intend to submit a patch for review that exposes this functionality
through the "expression" command and through the SB API.  That patch
also includes a testcase for all of this.

<rdar://problem/22864976>

llvm-svn: 264095

1 files changed, 6 insertions, 3 deletions

diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionHelper.h b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionHelper.h
index bb620def691..bcd30ec4af2 100644
--- a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionHelper.h
+++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionHelper.h
@@ -67,11 +67,14 @@ public:
     ///     the ASTs to after transformation.
     //------------------------------------------------------------------
     virtual clang::ASTConsumer *
-    ASTTransformer (clang::ASTConsumer *passthrough) = 0;
-    
+    ASTTransformer(clang::ASTConsumer *passthrough) = 0;
 
-protected:
+    virtual void
+    CommitPersistentDecls()
+    {
+    }
 
+protected:
 };
 
 } // namespace lldb_private