[OPENMP 4.0] Use 'declare reduction' constructs in 'reduction' clauses.

OpenMP 4.0 allows to define custom reduction operations using '#pragma
omp declare reduction' construct. Patch allows to use this custom
defined reduction operations in 'reduction' clauses.

llvm-svn: 263701

1 files changed, 26 insertions, 3 deletions

diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h
index ffffb7757c2..6f09c0f5355 100644
--- a/clang/lib/Sema/TreeTransform.h
+++ b/clang/lib/Sema/TreeTransform.h
@@ -1561,10 +1561,11 @@ public:
                                        SourceLocation ColonLoc,
                                        SourceLocation EndLoc,
                                        CXXScopeSpec &ReductionIdScopeSpec,
-                                       const DeclarationNameInfo &ReductionId) {
+                                       const DeclarationNameInfo &ReductionId,
+                                       ArrayRef<Expr *> UnresolvedReductions) {
     return getSema().ActOnOpenMPReductionClause(
         VarList, StartLoc, LParenLoc, ColonLoc, EndLoc, ReductionIdScopeSpec,
-        ReductionId);
+        ReductionId, UnresolvedReductions);
   }
 
   /// \brief Build a new OpenMP 'linear' clause.
@@ -7791,9 +7792,31 @@ TreeTransform<Derived>::TransformOMPReductionClause(OMPReductionClause *C) {
     if (!NameInfo.getName())
       return nullptr;
   }
+  // Build a list of all UDR decls with the same names ranged by the Scopes.
+  // The Scope boundary is a duplication of the previous decl.
+  llvm::SmallVector<Expr *, 16> UnresolvedReductions;
+  for (auto *E : C->reduction_ops()) {
+    // Transform all the decls.
+    if (E) {
+      auto *ULE = cast<UnresolvedLookupExpr>(E);
+      UnresolvedSet<8> Decls;
+      for (auto *D : ULE->decls()) {
+        NamedDecl *InstD =
+            cast<NamedDecl>(getDerived().TransformDecl(E->getExprLoc(), D));
+        Decls.addDecl(InstD, InstD->getAccess());
+      }
+      UnresolvedReductions.push_back(
+       UnresolvedLookupExpr::Create(
+          SemaRef.Context, /*NamingClass=*/nullptr,
+          ReductionIdScopeSpec.getWithLocInContext(SemaRef.Context),
+          NameInfo, /*ADL=*/true, ULE->isOverloaded(),
+          Decls.begin(), Decls.end()));
+    } else
+      UnresolvedReductions.push_back(nullptr);
+  }
   return getDerived().RebuildOMPReductionClause(
       Vars, C->getLocStart(), C->getLParenLoc(), C->getColonLoc(),
-      C->getLocEnd(), ReductionIdScopeSpec, NameInfo);
+      C->getLocEnd(), ReductionIdScopeSpec, NameInfo, UnresolvedReductions);
 }
 
 template <typename Derived>