[flang-commits] [flang] [flang][OpenMP] Support custom mappers in target update to/from clauses (PR #169673)

[Krish Gupta via flang-commits]

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@@ -1848,32 +1851,49 @@ void OmpVisitor::Post(const parser::OmpStylizedInstance &x) { //
 bool OmpVisitor::Pre(const parser::OmpMapClause &x) {
   auto &mods{OmpGetModifiers(x)};
   if (auto *mapper{OmpGetUniqueModifier<parser::OmpMapper>(mods)}) {
-    if (auto *symbol{FindSymbol(currScope(), mapper->v)}) {
-      // TODO: Do we need a specific flag or type here, to distinghuish against
-      // other ConstructName things? Leaving this for the full implementation
-      // of mapper lowering.
-      auto &ultimate{symbol->GetUltimate()};
-      auto *misc{ultimate.detailsIf<MiscDetails>()};
-      auto *md{ultimate.detailsIf<MapperDetails>()};
-      if (!md && (!misc || misc->kind() != MiscDetails::Kind::ConstructName))
-        context().Say(mapper->v.source,
-            "Name '%s' should be a mapper name"_err_en_US, mapper->v.source);
-      else
-        mapper->v.symbol = symbol;
+    ResolveMapperModifier(const_cast<parser::OmpMapper &>(*mapper));
+  }
+  return true;
+}
+
+bool OmpVisitor::Pre(const parser::OmpClause::To &x) {
+  auto &mods{OmpGetModifiers(x.v)};
+  if (auto *mapper{OmpGetUniqueModifier<parser::OmpMapper>(mods)}) {
+    ResolveMapperModifier(const_cast<parser::OmpMapper &>(*mapper));
+  }
+  return true;
+}
+
+bool OmpVisitor::Pre(const parser::OmpClause::From &x) {
+  auto &mods{OmpGetModifiers(x.v)};
+  if (auto *mapper{OmpGetUniqueModifier<parser::OmpMapper>(mods)}) {
+    ResolveMapperModifier(const_cast<parser::OmpMapper &>(*mapper));
+  }
+  return true;
+}
+
+void OmpVisitor::ResolveMapperModifier(parser::OmpMapper &mapper) {
+  if (auto *symbol{FindSymbol(currScope(), mapper.v)}) {
+    auto &ultimate{symbol->GetUltimate()};
+    auto *misc{ultimate.detailsIf<MiscDetails>()};
+    auto *md{ultimate.detailsIf<MapperDetails>()};
+    if (!md && (!misc || misc->kind() != MiscDetails::Kind::ConstructName))
+      context().Say(mapper.v.source,
+          "Name '%s' should be a mapper name"_err_en_US, mapper.v.source);
+    else
+      mapper.v.symbol = symbol;
+  } else {
+    // Allow the special 'default' mapper identifier without prior
+    // declaration so lowering can recognize and handle it. Emit an
+    // error for any other missing mapper identifier.
+    if (mapper.v.source.ToString() == "default") {
+      mapper.v.symbol =
+          &MakeSymbol(mapper.v, MiscDetails{MiscDetails::Kind::ConstructName});
     } else {
-      // Allow the special 'default' mapper identifier without prior
-      // declaration so lowering can recognize and handle it. Emit an
-      // error for any other missing mapper identifier.
-      if (mapper->v.source.ToString() == "default") {
-        mapper->v.symbol = &MakeSymbol(
-            mapper->v, MiscDetails{MiscDetails::Kind::ConstructName});
-      } else {
-        context().Say(
-            mapper->v.source, "'%s' not declared"_err_en_US, mapper->v.source);
-      }
+      context().Say(
+          mapper.v.source, "'%s' not declared"_err_en_US, mapper.v.source);
     }
   }
-  return true;
 }
 
 void OmpVisitor::ProcessMapperSpecifier(const parser::OmpMapperSpecifier &spec,
----------------
KrxGu wrote:

Good catch - I've kept only the necessary changes for const correctness. The formatting is now aligned with the functional changes.

https://github.com/llvm/llvm-project/pull/169673