[Clang Interpreter] Initial patch for the constexpr interpreter

Summary:
This patch introduces the skeleton of the constexpr interpreter,
capable of evaluating a simple constexpr functions consisting of
if statements. The interpreter is described in more detail in the
RFC. Further patches will add more features.

Reviewers: Bigcheese, jfb, rsmith

Subscribers: bruno, uenoku, ldionne, Tyker, thegameg, tschuett, dexonsmith, mgorny, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64146

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@370476 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 10 insertions, 0 deletions

diff --git a/include/clang/AST/ASTContext.h b/include/clang/AST/ASTContext.h
index 816f665fed..4ce30b7e7e 100644
--- a/include/clang/AST/ASTContext.h
+++ b/include/clang/AST/ASTContext.h
@@ -139,6 +139,12 @@ class FullComment;
 
 } // namespace comments
 
+namespace interp {
+
+class Context;
+
+} // namespace interp
+
 struct TypeInfo {
   uint64_t Width = 0;
   unsigned Align = 0;
@@ -564,6 +570,7 @@ private:
   const TargetInfo *Target = nullptr;
   const TargetInfo *AuxTarget = nullptr;
   clang::PrintingPolicy PrintingPolicy;
+  std::unique_ptr<interp::Context> InterpContext;
 
 public:
   IdentifierTable &Idents;
@@ -573,6 +580,9 @@ public:
   IntrusiveRefCntPtr<ExternalASTSource> ExternalSource;
   ASTMutationListener *Listener = nullptr;
 
+  /// Returns the clang bytecode interpreter context.
+  interp::Context &getInterpContext();
+
   /// Container for either a single DynTypedNode or for an ArrayRef to
   /// DynTypedNode. For use with ParentMap.
   class DynTypedNodeList {