Basic support for name mangling of C++11 lambda expressions. Because

name mangling in the Itanium C++ ABI for lambda expressions is so
dependent on context, we encode the number used to encode each lambda
as part of the lambda closure type, and maintain this value within
Sema.

Note that there are a several pieces still missing:
  - We still get the linkage of lambda expressions wrong
  - We aren't properly numbering or mangling lambda expressions that
  occur in default function arguments or in data member initializers.
  - We aren't (de-)serializing the lambda numbering tables




git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@150982 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 12 insertions, 2 deletions

diff --git a/lib/Sema/SemaLambda.cpp b/lib/Sema/SemaLambda.cpp
index 1a362d48e2..d1f87a2c18 100644
--- a/lib/Sema/SemaLambda.cpp
+++ b/lib/Sema/SemaLambda.cpp
@@ -483,7 +483,9 @@ static void addBlockPointerConversion(Sema &S,
 }
 
 ExprResult Sema::ActOnLambdaExpr(SourceLocation StartLoc, Stmt *Body, 
-                                 Scope *CurScope, bool IsInstantiation) {
+                                 Scope *CurScope, 
+                                 llvm::Optional<unsigned> ManglingNumber,
+                                 bool IsInstantiation) {
   // Leave the expression-evaluation context.
   DiscardCleanupsInEvaluationContext();
   PopExpressionEvaluationContext();
@@ -633,11 +635,19 @@ ExprResult Sema::ActOnLambdaExpr(SourceLocation StartLoc, Stmt *Body,
   if (LambdaExprNeedsCleanups)
     ExprNeedsCleanups = true;
 
+  // If we don't already have a mangling number for this lambda expression,
+  // allocate one now.
+  if (!ManglingNumber) {
+    // FIXME: Default arguments, data member initializers are special.
+    ManglingNumber = Context.getLambdaManglingNumber(CallOperator);
+  }
+  
   LambdaExpr *Lambda = LambdaExpr::Create(Context, Class, IntroducerRange, 
                                           CaptureDefault, Captures, 
                                           ExplicitParams, ExplicitResultType,
                                           CaptureInits, ArrayIndexVars, 
-                                          ArrayIndexStarts, Body->getLocEnd());
+                                          ArrayIndexStarts, Body->getLocEnd(),
+                                          *ManglingNumber);
 
   // C++11 [expr.prim.lambda]p2:
   //   A lambda-expression shall not appear in an unevaluated operand