[flang][fir][OpenMP] Refactor privtization code into shared location (llvm#141767)

ergawy · web-flow · commit f8dcb059ae06 · 2025-05-29T13:13:44.000+02:00
Refactors the utils needed to create privtization/locatization ops for
both the fir and OpenMP dialects into a shared location isolating OpenMP
stuff out of it as much as possible.
diff --git a/flang/include/flang/Lower/Support/Utils.h b/flang/include/flang/Lower/Support/Utils.h
@@ -94,6 +94,14 @@ bool isEqual(const Fortran::lower::SomeExpr *x,
              const Fortran::lower::SomeExpr *y);
 bool isEqual(const Fortran::lower::ExplicitIterSpace::ArrayBases &x,
              const Fortran::lower::ExplicitIterSpace::ArrayBases &y);
+
+template <typename OpType, typename OperandsStructType>
+void privatizeSymbol(
+    lower::AbstractConverter &converter, fir::FirOpBuilder &firOpBuilder,
+    lower::SymMap &symTable, std::function<void(OpType, mlir::Type)> initGen,
+    llvm::SetVector<const semantics::Symbol *> &allPrivatizedSymbols,
+    const semantics::Symbol *symToPrivatize, OperandsStructType *clauseOps);
+
 } // end namespace Fortran::lower
 
 // DenseMapInfo for pointers to Fortran::lower::SomeExpr.
diff --git a/flang/lib/Lower/Bridge.cpp b/flang/lib/Lower/Bridge.cpp
@@ -2029,10 +2029,6 @@ class FirConverter : public Fortran::lower::AbstractConverter {
   void handleLocalitySpecs(const IncrementLoopInfo &info) {
     Fortran::semantics::SemanticsContext &semanticsContext =
         bridge.getSemanticsContext();
-    // TODO Extract `DataSharingProcessor` from omp to a more general location.
-    Fortran::lower::omp::DataSharingProcessor dsp(
-        *this, semanticsContext, getEval(),
-        /*useDelayedPrivatization=*/true, localSymbols);
     fir::LocalitySpecifierOperands privateClauseOps;
     auto doConcurrentLoopOp =
         mlir::dyn_cast_if_present<fir::DoConcurrentLoopOp>(info.loopOp);
@@ -2041,10 +2037,17 @@ class FirConverter : public Fortran::lower::AbstractConverter {
     // complete.
     bool useDelayedPriv =
         enableDelayedPrivatizationStaging && doConcurrentLoopOp;
+    llvm::SetVector<const Fortran::semantics::Symbol *> allPrivatizedSymbols;
 
     for (const Fortran::semantics::Symbol *sym : info.localSymList) {
       if (useDelayedPriv) {
-        dsp.privatizeSymbol<fir::LocalitySpecifierOp>(sym, &privateClauseOps);
+        Fortran::lower::privatizeSymbol<fir::LocalitySpecifierOp>(
+            *this, this->getFirOpBuilder(), localSymbols,
+            [this](fir::LocalitySpecifierOp result, mlir::Type argType) {
+              TODO(this->toLocation(),
+                   "Localizers that need init regions are not supported yet.");
+            },
+            allPrivatizedSymbols, sym, &privateClauseOps);
         continue;
       }
 
@@ -2053,7 +2056,13 @@ class FirConverter : public Fortran::lower::AbstractConverter {
 
     for (const Fortran::semantics::Symbol *sym : info.localInitSymList) {
       if (useDelayedPriv) {
-        dsp.privatizeSymbol<fir::LocalitySpecifierOp>(sym, &privateClauseOps);
+        Fortran::lower::privatizeSymbol<fir::LocalitySpecifierOp>(
+            *this, this->getFirOpBuilder(), localSymbols,
+            [this](fir::LocalitySpecifierOp result, mlir::Type argType) {
+              TODO(this->toLocation(),
+                   "Localizers that need init regions are not supported yet.");
+            },
+            allPrivatizedSymbols, sym, &privateClauseOps);
         continue;
       }
 
@@ -2083,7 +2092,7 @@ class FirConverter : public Fortran::lower::AbstractConverter {
           builder->getArrayAttr(privateClauseOps.privateSyms));
 
       for (auto [sym, privateVar] : llvm::zip_equal(
-               dsp.getAllSymbolsToPrivatize(), privateClauseOps.privateVars)) {
+               allPrivatizedSymbols, privateClauseOps.privateVars)) {
         auto arg = doConcurrentLoopOp.getRegion().begin()->addArgument(
             privateVar.getType(), doConcurrentLoopOp.getLoc());
         bindSymbol(*sym, hlfir::translateToExtendedValue(
diff --git a/flang/lib/Lower/OpenMP/DataSharingProcessor.cpp b/flang/lib/Lower/OpenMP/DataSharingProcessor.cpp
@@ -16,6 +16,7 @@
 #include "Utils.h"
 #include "flang/Lower/ConvertVariable.h"
 #include "flang/Lower/PFTBuilder.h"
+#include "flang/Lower/Support/Utils.h"
 #include "flang/Lower/SymbolMap.h"
 #include "flang/Optimizer/Builder/BoxValue.h"
 #include "flang/Optimizer/Builder/HLFIRTools.h"
@@ -527,188 +528,48 @@ void DataSharingProcessor::copyLastPrivatize(mlir::Operation *op) {
     }
 }
 
-template <typename OpType, typename OperandsStructType>
 void DataSharingProcessor::privatizeSymbol(
-    const semantics::Symbol *symToPrivatize, OperandsStructType *clauseOps) {
+    const semantics::Symbol *symToPrivatize,
+    mlir::omp::PrivateClauseOps *clauseOps) {
   if (!useDelayedPrivatization) {
     cloneSymbol(symToPrivatize);
     copyFirstPrivateSymbol(symToPrivatize);
     return;
   }
 
-  const semantics::Symbol *sym = symToPrivatize->HasLocalLocality()
-                                     ? &symToPrivatize->GetUltimate()
-                                     : symToPrivatize;
-  lower::SymbolBox hsb = symToPrivatize->HasLocalLocality()
-                             ? converter.shallowLookupSymbol(*sym)
-                             : converter.lookupOneLevelUpSymbol(*sym);
-  assert(hsb && "Host symbol box not found");
-  hlfir::Entity entity{hsb.getAddr()};
-  bool cannotHaveNonDefaultLowerBounds = !entity.mayHaveNonDefaultLowerBounds();
-
-  mlir::Location symLoc = hsb.getAddr().getLoc();
-  std::string privatizerName = sym->name().ToString() + ".privatizer";
-  bool isFirstPrivate =
-      symToPrivatize->test(semantics::Symbol::Flag::OmpFirstPrivate) ||
-      symToPrivatize->test(semantics::Symbol::Flag::LocalityLocalInit);
-
-  mlir::Value privVal = hsb.getAddr();
-  mlir::Type allocType = privVal.getType();
-  if (!mlir::isa<fir::PointerType>(privVal.getType()))
-    allocType = fir::unwrapRefType(privVal.getType());
-
-  if (auto poly = mlir::dyn_cast<fir::ClassType>(allocType)) {
-    if (!mlir::isa<fir::PointerType>(poly.getEleTy()) && isFirstPrivate)
-      TODO(symLoc, "create polymorphic host associated copy");
-  }
-
-  // fir.array<> cannot be converted to any single llvm type and fir helpers
-  // are not available in openmp to llvmir translation so we cannot generate
-  // an alloca for a fir.array type there. Get around this by boxing all
-  // arrays.
-  if (mlir::isa<fir::SequenceType>(allocType)) {
-    entity = genVariableBox(symLoc, firOpBuilder, entity);
-    privVal = entity.getBase();
-    allocType = privVal.getType();
-  }
-
-  if (mlir::isa<fir::BaseBoxType>(privVal.getType())) {
-    // Boxes should be passed by reference into nested regions:
-    auto oldIP = firOpBuilder.saveInsertionPoint();
-    firOpBuilder.setInsertionPointToStart(firOpBuilder.getAllocaBlock());
-    auto alloca = firOpBuilder.create<fir::AllocaOp>(symLoc, privVal.getType());
-    firOpBuilder.restoreInsertionPoint(oldIP);
-    firOpBuilder.create<fir::StoreOp>(symLoc, privVal, alloca);
-    privVal = alloca;
-  }
-
-  mlir::Type argType = privVal.getType();
-
-  OpType privatizerOp = [&]() {
-    auto moduleOp = firOpBuilder.getModule();
-    auto uniquePrivatizerName = fir::getTypeAsString(
-        allocType, converter.getKindMap(),
-        converter.mangleName(*sym) +
-            (isFirstPrivate ? "_firstprivate" : "_private"));
-
-    if (auto existingPrivatizer =
-            moduleOp.lookupSymbol<OpType>(uniquePrivatizerName))
-      return existingPrivatizer;
-
-    mlir::OpBuilder::InsertionGuard guard(firOpBuilder);
-    firOpBuilder.setInsertionPointToStart(moduleOp.getBody());
-    OpType result;
-
-    if constexpr (std::is_same_v<OpType, mlir::omp::PrivateClauseOp>) {
-      result = firOpBuilder.create<OpType>(
-          symLoc, uniquePrivatizerName, allocType,
-          isFirstPrivate ? mlir::omp::DataSharingClauseType::FirstPrivate
-                         : mlir::omp::DataSharingClauseType::Private);
-    } else {
-      result = firOpBuilder.create<OpType>(
-          symLoc, uniquePrivatizerName, allocType,
-          isFirstPrivate ? fir::LocalitySpecifierType::LocalInit
-                         : fir::LocalitySpecifierType::Local);
-    }
-
-    fir::ExtendedValue symExV = converter.getSymbolExtendedValue(*sym);
-    lower::SymMapScope outerScope(symTable);
-
-    // Populate the `init` region.
-    // We need to initialize in the following cases:
-    // 1. The allocation was for a derived type which requires initialization
-    //    (this can be skipped if it will be initialized anyway by the copy
-    //    region, unless the derived type has allocatable components)
-    // 2. The allocation was for any kind of box
-    // 3. The allocation was for a boxed character
-    const bool needsInitialization =
-        (Fortran::lower::hasDefaultInitialization(sym->GetUltimate()) &&
-         (!isFirstPrivate || hlfir::mayHaveAllocatableComponent(allocType))) ||
-        mlir::isa<fir::BaseBoxType>(allocType) ||
-        mlir::isa<fir::BoxCharType>(allocType);
-    if (needsInitialization) {
-      mlir::Region &initRegion = result.getInitRegion();
-      mlir::Block *initBlock = firOpBuilder.createBlock(
-          &initRegion, /*insertPt=*/{}, {argType, argType}, {symLoc, symLoc});
-
-      populateByRefInitAndCleanupRegions(
-          converter, symLoc, argType, /*scalarInitValue=*/nullptr, initBlock,
-          result.getInitPrivateArg(), result.getInitMoldArg(),
-          result.getDeallocRegion(),
-          isFirstPrivate ? DeclOperationKind::FirstPrivate
-                         : DeclOperationKind::Private,
-          sym, cannotHaveNonDefaultLowerBounds);
-      // TODO: currently there are false positives from dead uses of the mold
-      // arg
-      if (result.initReadsFromMold())
-        mightHaveReadHostSym.insert(sym);
-    }
-
-    // Populate the `copy` region if this is a `firstprivate`.
-    if (isFirstPrivate) {
-      mlir::Region &copyRegion = result.getCopyRegion();
-      // First block argument corresponding to the original/host value while
-      // second block argument corresponding to the privatized value.
-      mlir::Block *copyEntryBlock = firOpBuilder.createBlock(
-          &copyRegion, /*insertPt=*/{}, {argType, argType}, {symLoc, symLoc});
-      firOpBuilder.setInsertionPointToEnd(copyEntryBlock);
-
-      auto addSymbol = [&](unsigned argIdx, const semantics::Symbol *symToMap,
-                           bool force = false) {
-        symExV.match(
-            [&](const fir::MutableBoxValue &box) {
-              symTable.addSymbol(
-                  *symToMap,
-                  fir::substBase(box, copyRegion.getArgument(argIdx)), force);
-            },
-            [&](const auto &box) {
-              symTable.addSymbol(*symToMap, copyRegion.getArgument(argIdx),
-                                 force);
-            });
-      };
-
-      addSymbol(0, sym, true);
-      lower::SymMapScope innerScope(symTable);
-      addSymbol(1, symToPrivatize);
-
-      auto ip = firOpBuilder.saveInsertionPoint();
-      copyFirstPrivateSymbol(symToPrivatize, &ip);
-
-      if constexpr (std::is_same_v<OpType, mlir::omp::PrivateClauseOp>) {
-        firOpBuilder.create<mlir::omp::YieldOp>(
-            hsb.getAddr().getLoc(),
-            symTable.shallowLookupSymbol(*symToPrivatize).getAddr());
-      } else {
-        firOpBuilder.create<fir::YieldOp>(
-            hsb.getAddr().getLoc(),
-            symTable.shallowLookupSymbol(*symToPrivatize).getAddr());
-      }
-    }
-
-    return result;
-  }();
-
-  if (clauseOps) {
-    clauseOps->privateSyms.push_back(mlir::SymbolRefAttr::get(privatizerOp));
-    clauseOps->privateVars.push_back(privVal);
-  }
+  auto initGen = [&](mlir::omp::PrivateClauseOp result, mlir::Type argType) {
+    lower::SymbolBox hsb = converter.lookupOneLevelUpSymbol(*symToPrivatize);
+    assert(hsb && "Host symbol box not found");
+    hlfir::Entity entity{hsb.getAddr()};
+    bool cannotHaveNonDefaultLowerBounds =
+        !entity.mayHaveNonDefaultLowerBounds();
+
+    mlir::Region &initRegion = result.getInitRegion();
+    mlir::Location symLoc = hsb.getAddr().getLoc();
+    mlir::Block *initBlock = firOpBuilder.createBlock(
+        &initRegion, /*insertPt=*/{}, {argType, argType}, {symLoc, symLoc});
+
+    bool emitCopyRegion =
+        symToPrivatize->test(semantics::Symbol::Flag::OmpFirstPrivate);
+
+    populateByRefInitAndCleanupRegions(
+        converter, symLoc, argType, /*scalarInitValue=*/nullptr, initBlock,
+        result.getInitPrivateArg(), result.getInitMoldArg(),
+        result.getDeallocRegion(),
+        emitCopyRegion ? omp::DeclOperationKind::FirstPrivate
+                       : omp::DeclOperationKind::Private,
+        symToPrivatize, cannotHaveNonDefaultLowerBounds);
+    // TODO: currently there are false positives from dead uses of the mold
+    // arg
+    if (result.initReadsFromMold())
+      mightHaveReadHostSym.insert(symToPrivatize);
+  };
 
-  if (symToPrivatize->HasLocalLocality())
-    allPrivatizedSymbols.insert(symToPrivatize);
+  Fortran::lower::privatizeSymbol<mlir::omp::PrivateClauseOp,
+                                  mlir::omp::PrivateClauseOps>(
+      converter, firOpBuilder, symTable, initGen, allPrivatizedSymbols,
+      symToPrivatize, clauseOps);
 }
-
-template void
-DataSharingProcessor::privatizeSymbol<mlir::omp::PrivateClauseOp,
-                                      mlir::omp::PrivateClauseOps>(
-    const semantics::Symbol *symToPrivatize,
-    mlir::omp::PrivateClauseOps *clauseOps);
-
-template void
-DataSharingProcessor::privatizeSymbol<fir::LocalitySpecifierOp,
-                                      fir::LocalitySpecifierOperands>(
-    const semantics::Symbol *symToPrivatize,
-    fir::LocalitySpecifierOperands *clauseOps);
-
 } // namespace omp
 } // namespace lower
 } // namespace Fortran
diff --git a/flang/lib/Lower/OpenMP/DataSharingProcessor.h b/flang/lib/Lower/OpenMP/DataSharingProcessor.h
@@ -153,10 +153,8 @@ class DataSharingProcessor {
                : llvm::ArrayRef<const semantics::Symbol *>();
   }
 
-  template <typename OpType = mlir::omp::PrivateClauseOp,
-            typename OperandsStructType = mlir::omp::PrivateClauseOps>
   void privatizeSymbol(const semantics::Symbol *symToPrivatize,
-                       OperandsStructType *clauseOps);
+                       mlir::omp::PrivateClauseOps *clauseOps);
 };
 
 } // namespace omp
diff --git a/flang/lib/Lower/Support/Utils.cpp b/flang/lib/Lower/Support/Utils.cpp
