[OpenCL] Generate metadata for opencl_unroll_hint attribute

Add support for opencl_unroll_hint attribute from OpenCL v2.0 s6.11.5.

Reusing most of metadata generation from CGLoopInfo helper class.

The code is based on Khronos OpenCL compiler:
https://github.com/KhronosGroup/SPIR/tree/spirv-1.0

Patch by Liu Yaxun (Sam)!

Differential Revision: http://reviews.llvm.org/D16686

llvm-svn: 261350

2 files changed, 20 insertions, 2 deletions

diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp
index 64f00bfcfa5..24db6814b81 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -670,7 +670,7 @@ void Parser::ParseBorlandTypeAttributes(ParsedAttributes &attrs) {
   }
 }
 
-void Parser::ParseOpenCLAttributes(ParsedAttributes &attrs) {
+void Parser::ParseOpenCLKernelAttributes(ParsedAttributes &attrs) {
   // Treat these like attributes
   while (Tok.is(tok::kw___kernel)) {
     IdentifierInfo *AttrName = Tok.getIdentifierInfo();
@@ -3098,7 +3098,7 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
 
     // OpenCL single token adornments.
     case tok::kw___kernel:
-      ParseOpenCLAttributes(DS.getAttributes());
+      ParseOpenCLKernelAttributes(DS.getAttributes());
       continue;
 
     // Nullability type specifiers.
diff --git a/clang/lib/Parse/ParseStmt.cpp b/clang/lib/Parse/ParseStmt.cpp
index 71904f0cc22..085319f9bdd 100644
--- a/clang/lib/Parse/ParseStmt.cpp
+++ b/clang/lib/Parse/ParseStmt.cpp
@@ -107,6 +107,8 @@ Parser::ParseStatementOrDeclaration(StmtVector &Stmts,
 
   ParsedAttributesWithRange Attrs(AttrFactory);
   MaybeParseCXX11Attributes(Attrs, nullptr, /*MightBeObjCMessageSend*/ true);
+  if (!MaybeParseOpenCLUnrollHintAttribute(Attrs))
+    return StmtError();
 
   StmtResult Res = ParseStatementOrDeclarationAfterAttributes(
       Stmts, Allowed, TrailingElseLoc, Attrs);
@@ -2208,3 +2210,19 @@ void Parser::ParseMicrosoftIfExistsStatement(StmtVector &Stmts) {
   }
   Braces.consumeClose();
 }
+
+bool Parser::ParseOpenCLUnrollHintAttribute(ParsedAttributes &Attrs) {
+  MaybeParseGNUAttributes(Attrs);
+
+  if (Attrs.empty())
+    return true;
+
+  if (Attrs.getList()->getKind() != AttributeList::AT_OpenCLUnrollHint)
+    return true;
+
+  if (!(Tok.is(tok::kw_for) || Tok.is(tok::kw_while) || Tok.is(tok::kw_do))) {
+    Diag(Tok, diag::err_opencl_unroll_hint_on_non_loop);
+    return false;
+  }
+  return true;
+}