1 files changed, 25 insertions, 12 deletions
diff --git a/lib/CodeGen/CGOpenCLRuntime.cpp b/lib/CodeGen/CGOpenCLRuntime.cpp
index 7f6f595dd5..191a95c629 100644
--- a/lib/CodeGen/CGOpenCLRuntime.cpp
+++ b/lib/CodeGen/CGOpenCLRuntime.cpp
@@ -1,9 +1,8 @@
 //===----- CGOpenCLRuntime.cpp - Interface to OpenCL Runtimes -------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
@@ -123,6 +122,23 @@ llvm::PointerType *CGOpenCLRuntime::getGenericVoidPointerType() {
       CGM.getContext().getTargetAddressSpace(LangAS::opencl_generic));
 }
 
+// Get the block literal from an expression derived from the block expression.
+// OpenCL v2.0 s6.12.5:
+// Block variable declarations are implicitly qualified with const. Therefore
+// all block variables must be initialized at declaration time and may not be
+// reassigned.
+static const BlockExpr *getBlockExpr(const Expr *E) {
+  const Expr *Prev = nullptr; // to make sure we do not stuck in infinite loop.
+  while(!isa<BlockExpr>(E) && E != Prev) {
+    Prev = E;
+    E = E->IgnoreCasts();
+    if (auto DR = dyn_cast<DeclRefExpr>(E)) {
+      E = cast<VarDecl>(DR->getDecl())->getInit();
+    }
+  }
+  return cast<BlockExpr>(E);
+}
+
 /// Record emitted llvm invoke function and llvm block literal for the
 /// corresponding block expression.
 void CGOpenCLRuntime::recordBlockInfo(const BlockExpr *E,
@@ -137,20 +153,17 @@ void CGOpenCLRuntime::recordBlockInfo(const BlockExpr *E,
   EnqueuedBlockMap[E].Kernel = nullptr;
 }
 
+llvm::Function *CGOpenCLRuntime::getInvokeFunction(const Expr *E) {
+  return EnqueuedBlockMap[getBlockExpr(E)].InvokeFunc;
+}
+
 CGOpenCLRuntime::EnqueuedBlockInfo
 CGOpenCLRuntime::emitOpenCLEnqueuedBlock(CodeGenFunction &CGF, const Expr *E) {
   CGF.EmitScalarExpr(E);
 
   // The block literal may be assigned to a const variable. Chasing down
   // to get the block literal.
-  if (auto DR = dyn_cast<DeclRefExpr>(E)) {
-    E = cast<VarDecl>(DR->getDecl())->getInit();
-  }
-  E = E->IgnoreImplicit();
-  if (auto Cast = dyn_cast<CastExpr>(E)) {
-    E = Cast->getSubExpr();
-  }
-  auto *Block = cast<BlockExpr>(E);
+  const BlockExpr *Block = getBlockExpr(E);
 
   assert(EnqueuedBlockMap.find(Block) != EnqueuedBlockMap.end() &&
          "Block expression not emitted");