[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

llvm-svn: 354817

1 files changed, 10 insertions, 0 deletions

diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index bed58d0e10b..9626418f686 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/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)