[flang-commits] [flang] [flang][OpenMP][NFC] Share SetSymbolDSA between semantics and lowering (PR #207826)

[via flang-commits]

https://github.com/chichunchen updated https://github.com/llvm/llvm-project/pull/207826

>From 65510ba80540c197b029baa9bdf68387c63a133f Mon Sep 17 00:00:00 2001
From: "Chi Chun, Chen" <chichun.chen at hpe.com>
Date: Thu, 2 Jul 2026 16:26:35 -0500
Subject: [PATCH] [flang][OpenMP][NFC] Share SetSymbolDSA between semantics and
 lowering

Move the DSA helper from the private OmpAttributeVisitor::SetSymbolDSA into the
public openmp-dsa header next to GetSymbolDSA, and share the DSA flag set
through a single GetDataSharingAttributeFlags().

This lets an upcoming metadirective lowering change reuse the helper to set the
predetermined DSA of the loop induction variables of a selected variant. A
loop-associated variant is resolved during lowering, so the usual semantic DSA
resolution never runs on its loop nest and lowering must set those flags itself.

Assisted with Copilot.
---
 flang/include/flang/Semantics/openmp-dsa.h |  4 ++++
 flang/lib/Semantics/openmp-dsa.cpp         | 22 +++++++++++++++++-----
 flang/lib/Semantics/resolve-directives.cpp | 15 +--------------
 3 files changed, 22 insertions(+), 19 deletions(-)

diff --git a/flang/include/flang/Semantics/openmp-dsa.h b/flang/include/flang/Semantics/openmp-dsa.h
index 4b94a679f29ef..a6e15ff965b29 100644
--- a/flang/include/flang/Semantics/openmp-dsa.h
+++ b/flang/include/flang/Semantics/openmp-dsa.h
@@ -13,8 +13,12 @@
 
 namespace Fortran::semantics {
 
+Symbol::Flags GetDataSharingAttributeFlags();
+
 Symbol::Flags GetSymbolDSA(const Symbol &symbol);
 
+void SetSymbolDSA(Symbol &symbol, Symbol::Flags flags);
+
 } // namespace Fortran::semantics
 
 #endif // FORTRAN_SEMANTICS_OPENMP_DSA_H_
diff --git a/flang/lib/Semantics/openmp-dsa.cpp b/flang/lib/Semantics/openmp-dsa.cpp
index 48aa36febe5c5..7aa5bf9c200b4 100644
--- a/flang/lib/Semantics/openmp-dsa.cpp
+++ b/flang/lib/Semantics/openmp-dsa.cpp
@@ -10,12 +10,14 @@
 
 namespace Fortran::semantics {
 
-Symbol::Flags GetSymbolDSA(const Symbol &symbol) {
-  Symbol::Flags dsaFlags{Symbol::Flag::OmpPrivate,
+Symbol::Flags GetDataSharingAttributeFlags() {
+  return Symbol::Flags{Symbol::Flag::OmpShared, Symbol::Flag::OmpPrivate,
       Symbol::Flag::OmpFirstPrivate, Symbol::Flag::OmpLastPrivate,
-      Symbol::Flag::OmpShared, Symbol::Flag::OmpLinear,
-      Symbol::Flag::OmpReduction};
-  Symbol::Flags dsa{symbol.flags() & dsaFlags};
+      Symbol::Flag::OmpReduction, Symbol::Flag::OmpLinear};
+}
+
+Symbol::Flags GetSymbolDSA(const Symbol &symbol) {
+  Symbol::Flags dsa{symbol.flags() & GetDataSharingAttributeFlags()};
   if (dsa.any()) {
     return dsa;
   }
@@ -26,4 +28,14 @@ Symbol::Flags GetSymbolDSA(const Symbol &symbol) {
   return {};
 }
 
+// Clear any previous data-sharing attribute flags and set the new ones.
+// Needed when setting PreDetermined DSAs, that take precedence over Implicit
+// ones.
+void SetSymbolDSA(Symbol &symbol, Symbol::Flags flags) {
+  symbol.flags() &= ~(GetDataSharingAttributeFlags() |
+      Symbol::Flags{Symbol::Flag::OmpExplicit, Symbol::Flag::OmpImplicit,
+          Symbol::Flag::OmpPreDetermined});
+  symbol.flags() |= flags;
+}
+
 } // namespace Fortran::semantics
diff --git a/flang/lib/Semantics/resolve-directives.cpp b/flang/lib/Semantics/resolve-directives.cpp
index cd4b986858d7e..51ad81bcbc2ef 100644
--- a/flang/lib/Semantics/resolve-directives.cpp
+++ b/flang/lib/Semantics/resolve-directives.cpp
@@ -982,10 +982,7 @@ class OmpAttributeVisitor : DirectiveAttributeVisitor<llvm::omp::Directive> {
   }
 
 private:
-  Symbol::Flags dataSharingAttributeFlags{Symbol::Flag::OmpShared,
-      Symbol::Flag::OmpPrivate, Symbol::Flag::OmpFirstPrivate,
-      Symbol::Flag::OmpLastPrivate, Symbol::Flag::OmpReduction,
-      Symbol::Flag::OmpLinear};
+  Symbol::Flags dataSharingAttributeFlags{GetDataSharingAttributeFlags()};
 
   Symbol::Flags dataMappingAttributeFlags{Symbol::Flag::OmpMapTo,
       Symbol::Flag::OmpMapFrom, Symbol::Flag::OmpMapToFrom,
@@ -1055,16 +1052,6 @@ class OmpAttributeVisitor : DirectiveAttributeVisitor<llvm::omp::Directive> {
       symbol.set(Symbol::Flag::OmpExplicit);
     }
   }
-
-  // Clear any previous data-sharing attribute flags and set the new ones.
-  // Needed when setting PreDetermined DSAs, that take precedence over
-  // Implicit ones.
-  void SetSymbolDSA(Symbol &symbol, Symbol::Flags flags) {
-    symbol.flags() &= ~(dataSharingAttributeFlags |
-        Symbol::Flags{Symbol::Flag::OmpExplicit, Symbol::Flag::OmpImplicit,
-            Symbol::Flag::OmpPreDetermined});
-    symbol.flags() |= flags;
-  }
 };
 
 void ResolveAccParts(SemanticsContext &context, const parser::ProgramUnit &node,