[OpenMP 5.0] Parsing/sema support for from clause with mapper modifier.

This patch implements the parsing and sema support for the OpenMP
'from'-clause with potential user-defined mappers attached.
User-defined mappers are a new feature in OpenMP 5.0. A 'from'-clause
can have an explicit or implicit associated mapper, which instructs the
compiler to generate and use customized mapping functions. An example is
shown below:

    struct S { int len; int *d; };
    #pragma omp declare mapper(id: struct S s) map(s, s.d[0:s.len])
    struct S ss;
    #pragma omp target update from(mapper(id): ss) // use the mapper with name 'id' to map ss from device

Contributed-by: Lingda Li <lildmh@gmail.com>

Differential Revision: https://reviews.llvm.org/D58638

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@354817 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 14 insertions, 0 deletions

diff --git a/lib/Serialization/ASTReader.cpp b/lib/Serialization/ASTReader.cpp
index bed58d0e10..9626418f68 100644
--- a/lib/Serialization/ASTReader.cpp
+++ b/lib/Serialization/ASTReader.cpp
@@ -12448,6 +12448,10 @@ void OMPClauseReader::VisitOMPToClause(OMPToClause *C) {
 
 void OMPClauseReader::VisitOMPFromClause(OMPFromClause *C) {
   C->setLParenLoc(Record.readSourceLocation());
+  C->setMapperQualifierLoc(Record.readNestedNameSpecifierLoc());
+  DeclarationNameInfo DNI;
+  Record.readDeclarationNameInfo(DNI);
+  C->setMapperIdInfo(DNI);
   auto NumVars = C->varlist_size();
   auto UniqueDecls = C->getUniqueDeclarationsNum();
   auto TotalLists = C->getTotalComponentListNum();
@@ -12459,6 +12463,12 @@ void OMPClauseReader::VisitOMPFromClause(OMPFromClause *C) {
     Vars.push_back(Record.readSubExpr());
   C->setVarRefs(Vars);
 
+  SmallVector<Expr *, 16> UDMappers;
+  UDMappers.reserve(NumVars);
+  for (unsigned I = 0; I < NumVars; ++I)
+    UDMappers.push_back(Record.readSubExpr());
+  C->setUDMapperRefs(UDMappers);
+
   SmallVector<ValueDecl *, 16> Decls;
   Decls.reserve(UniqueDecls);
   for (unsigned i = 0; i < UniqueDecls; ++i)
diff --git a/lib/Serialization/ASTWriter.cpp b/lib/Serialization/ASTWriter.cpp
index 1575a400ba..3d19c9d823 100644
--- a/lib/Serialization/ASTWriter.cpp
+++ b/lib/Serialization/ASTWriter.cpp
@@ -6885,8 +6885,12 @@ void OMPClauseWriter::VisitOMPFromClause(OMPFromClause *C) {
   Record.push_back(C->getTotalComponentListNum());
   Record.push_back(C->getTotalComponentsNum());
   Record.AddSourceLocation(C->getLParenLoc());
+  Record.AddNestedNameSpecifierLoc(C->getMapperQualifierLoc());
+  Record.AddDeclarationNameInfo(C->getMapperIdInfo());
   for (auto *E : C->varlists())
     Record.AddStmt(E);
+  for (auto *E : C->mapperlists())
+    Record.AddStmt(E);
   for (auto *D : C->all_decls())
     Record.AddDeclRef(D);
   for (auto N : C->all_num_lists())