[OPENMP 4.0] Initial support for 'omp declare reduction' construct.

Add parsing, sema analysis and serialization/deserialization for 'declare reduction' construct.
User-defined reductions are defined as

#pragma omp declare reduction( reduction-identifier : typename-list : combiner ) [initializer ( initializer-expr )]
These custom reductions may be used in 'reduction' clauses of OpenMP constructs. The combiner specifies how partial results can be combined into a single value. The
combiner can use the special variable identifiers omp_in and omp_out that are of the type of the variables being reduced with this reduction-identifier. Each of them will
denote one of the values to be combined before executing the combiner. It is assumed that the special omp_out identifier will refer to the storage that holds the resulting
combined value after executing the combiner.
As the initializer-expr value of a user-defined reduction is not known a priori the initializer-clause can be used to specify one. Then the contents of the initializer-clause
will be used as the initializer for private copies of reduction list items where the omp_priv identifier will refer to the storage to be initialized. The special identifier
omp_orig can also appear in the initializer-clause and it will refer to the storage of the original variable to be reduced.
Differential Revision: http://reviews.llvm.org/D11182

llvm-svn: 262582

1 files changed, 8 insertions, 0 deletions

diff --git a/clang/lib/Sema/SemaLookup.cpp b/clang/lib/Sema/SemaLookup.cpp
index 4baf6053359..00379336251 100644
--- a/clang/lib/Sema/SemaLookup.cpp
+++ b/clang/lib/Sema/SemaLookup.cpp
@@ -280,6 +280,10 @@ static inline unsigned getIDNS(Sema::LookupNameKind NameKind,
     IDNS = Decl::IDNS_ObjCProtocol;
     break;
 
+  case Sema::LookupOMPReductionName:
+    IDNS = Decl::IDNS_OMPReduction;
+    break;
+
   case Sema::LookupAnyName:
     IDNS = Decl::IDNS_Ordinary | Decl::IDNS_Tag | Decl::IDNS_Member
       | Decl::IDNS_Using | Decl::IDNS_Namespace | Decl::IDNS_ObjCProtocol
@@ -2015,6 +2019,10 @@ bool Sema::LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx,
       BaseCallback = &LookupAnyMember;
       break;
 
+    case LookupOMPReductionName:
+      BaseCallback = &CXXRecordDecl::FindOMPReductionMember;
+      break;
+
     case LookupUsingDeclName:
       // This lookup is for redeclarations only.