[OpenMP] Add support for nested 'declare target' directives

Add the capability to nest multiple declare target directives 
- including header files within a declare target region.

Differential Revision: https://reviews.llvm.org/D51378

Patch by Patrick Lyster

llvm-svn: 341766

2 files changed, 5 insertions, 10 deletions

diff --git a/clang/lib/Parse/ParseOpenMP.cpp b/clang/lib/Parse/ParseOpenMP.cpp
index b3c7e3a63d0..4da357bbbc7 100644
--- a/clang/lib/Parse/ParseOpenMP.cpp
+++ b/clang/lib/Parse/ParseOpenMP.cpp
@@ -775,8 +775,8 @@ Parser::DeclGroupPtrTy Parser::ParseOpenMPDeclarativeDirectiveWithExtDecl(
 
     llvm::SmallVector<Decl *, 4>  Decls;
     DKind = parseOpenMPDirectiveKind(*this);
-    while (DKind != OMPD_end_declare_target && DKind != OMPD_declare_target &&
-           Tok.isNot(tok::eof) && Tok.isNot(tok::r_brace)) {
+    while (DKind != OMPD_end_declare_target && Tok.isNot(tok::eof) &&
+           Tok.isNot(tok::r_brace)) {
       DeclGroupPtrTy Ptr;
       // Here we expect to see some function declaration.
       if (AS == AS_none) {
diff --git a/clang/lib/Sema/SemaOpenMP.cpp b/clang/lib/Sema/SemaOpenMP.cpp
index 215b4bf1090..3664f9a5fd4 100644
--- a/clang/lib/Sema/SemaOpenMP.cpp
+++ b/clang/lib/Sema/SemaOpenMP.cpp
@@ -12960,19 +12960,14 @@ bool Sema::ActOnStartOpenMPDeclareTargetDirective(SourceLocation Loc) {
     Diag(Loc, diag::err_omp_region_not_file_context);
     return false;
   }
-  if (IsInOpenMPDeclareTargetContext) {
-    Diag(Loc, diag::err_omp_enclosed_declare_target);
-    return false;
-  }
-
-  IsInOpenMPDeclareTargetContext = true;
+  ++DeclareTargetNestingLevel;
   return true;
 }
 
 void Sema::ActOnFinishOpenMPDeclareTargetDirective() {
-  assert(IsInOpenMPDeclareTargetContext &&
+  assert(DeclareTargetNestingLevel > 0 &&
          "Unexpected ActOnFinishOpenMPDeclareTargetDirective");
-  IsInOpenMPDeclareTargetContext = false;
+  --DeclareTargetNestingLevel;
 }
 
 void Sema::ActOnOpenMPDeclareTargetName(Scope *CurScope,