[flang-commits] [flang] [flang][OpenMP] Move privatizations out of sections (PR #88191)

[Leandro Lupori via flang-commits]

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@@ -1983,30 +1980,68 @@ genOMP(Fortran::lower::AbstractConverter &converter,
         std::get<Fortran::parser::OmpEndSectionsDirective>(sectionsConstruct.t);
     const auto &endSectionsClauseList =
         std::get<Fortran::parser::OmpClauseList>(endSectionsDirective.t);
-    ClauseProcessor(converter, semaCtx, endSectionsClauseList)
-        .processNowait(nowaitClauseOperand);
+    hasNowait = ClauseProcessor(converter, semaCtx, endSectionsClauseList)
+                    .processNowait(nowaitClauseOperand);
   }
 
+  // Insert privatizations before SECTIONS
+  symTable.pushScope();
+  DataSharingProcessor dsp(converter, semaCtx, sectionsClauseList, eval);
+  dsp.processStep1();
+
   // SECTIONS construct
-  genOpWithBody<mlir::omp::SectionsOp>(
+  auto sectionsOp = genOpWithBody<mlir::omp::SectionsOp>(
       OpWithBodyGenInfo(converter, semaCtx, currentLocation, eval)
           .setGenNested(false),
       /*reduction_vars=*/mlir::ValueRange(),
       /*reductions=*/nullptr, allocateOperands, allocatorOperands,
       nowaitClauseOperand);
 
+  std::optional<Clause> lastPrivateClause;
+  for (const Fortran::parser::OmpClause &clause : sectionsClauseList.v) {
+    if (std::holds_alternative<Fortran::parser::OmpClause::Lastprivate>(
+            clause.u)) {
+      lastPrivateClause = makeClause(clause, semaCtx);
+    }
+  }
+
   const auto &sectionBlocks =
       std::get<Fortran::parser::OmpSectionBlocks>(sectionsConstruct.t);
   auto &firOpBuilder = converter.getFirOpBuilder();
   auto ip = firOpBuilder.saveInsertionPoint();
-  for (const auto &[nblock, neval] :
-       llvm::zip(sectionBlocks.v, eval.getNestedEvaluations())) {
-    symTable.pushScope();
-    genSectionOp(converter, semaCtx, neval, /*genNested=*/true, currentLocation,
-                 sectionsClauseList);
-    symTable.popScope();
+  auto zippy = llvm::zip(sectionBlocks.v, eval.getNestedEvaluations());
+  auto it = zippy.begin(), next = it, end = zippy.end();
+  ++next;
+  for (; it != end; it = next, ++next) {
+    const auto &[nblock, neval] = *it;
+    mlir::omp::SectionOp sectionOp = genSectionOp(
+        converter, semaCtx, neval, /*genNested=*/true, currentLocation);
+    // For `omp.sections`, lastprivatized variables occur in
+    // lexically final `omp.section` operation.
+    if (next == end && lastPrivateClause) {
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luporl wrote:

Done in last commit.

https://github.com/llvm/llvm-project/pull/88191