[OpenACC][CIR] 'declare' lowering for globals/ns/struct-scopes (+create)

clang/lib/CIR/CodeGen/CIRGenDeclOpenACC.cpp

@@ -11,8 +11,11 @@
 //===----------------------------------------------------------------------===//
 
 #include "CIRGenFunction.h"
+#include "CIRGenOpenACCHelpers.h"
+
 #include "mlir/Dialect/OpenACC/OpenACC.h"
 #include "clang/AST/DeclOpenACC.h"
+#include "llvm/Support/SaveAndRestore.h"
 
 using namespace clang;
 using namespace clang::CIRGen;
@@ -96,6 +99,13 @@ struct OpenACCDeclareCleanup final : EHScopeStack::Cleanup {
 };
 } // namespace
 
+void CIRGenModule::emitGlobalOpenACCDecl(const OpenACCConstructDecl *d) {
+  if (const auto *rd = dyn_cast<OpenACCRoutineDecl>(d))
+    emitGlobalOpenACCRoutineDecl(rd);
+  else
+    emitGlobalOpenACCDeclareDecl(cast<OpenACCDeclareDecl>(d));
+}
+
 void CIRGenFunction::emitOpenACCDeclare(const OpenACCDeclareDecl &d) {
   mlir::Location exprLoc = cgm.getLoc(d.getBeginLoc());
   auto enterOp = mlir::acc::DeclareEnterOp::create(
@@ -109,15 +119,157 @@ void CIRGenFunction::emitOpenACCDeclare(const OpenACCDeclareDecl &d) {
                                              enterOp);
 }
 
+// Helper function that gets the declaration referenced by the declare clause.
+// This is a simplified verison of the work that `getOpenACCDataOperandInfo`
+// does, as it only has to get forms that 'declare' does.
+static const Decl *getDeclareReferencedDecl(const Expr *e) {
+  const Expr *curVarExpr = e->IgnoreParenImpCasts();
+
+  // Since we allow array sections, we have to unpack the array sections here.
+  // We don't have to worry about other bounds, since only variable or array
+  // name (plus array sections as an extension) are permitted.
+  while (const auto *ase = dyn_cast<ArraySectionExpr>(curVarExpr))
+    curVarExpr = ase->getBase()->IgnoreParenImpCasts();
+
+  if (const auto *DRE = dyn_cast<DeclRefExpr>(curVarExpr))
+    return DRE->getFoundDecl()->getCanonicalDecl();
+
+  // MemberExpr is allowed when it is implicit 'this'.
+  return cast<MemberExpr>(curVarExpr)->getMemberDecl()->getCanonicalDecl();
+}
+
+template <typename BeforeOpTy, typename DataClauseTy>
+void CIRGenModule::emitGlobalOpenACCDeclareDataOperands(
+    const Expr *varOperand, DataClauseTy dataClause,
+    OpenACCModifierKind modifiers, bool structured, bool implicit,
+    bool requiresDtor) {
+  // This is a template argument so that we don't have to include all of
+  // mlir::acc into CIRGenModule.
+  static_assert(std::is_same_v<DataClauseTy, mlir::acc::DataClause>);
+  mlir::Location exprLoc = getLoc(varOperand->getBeginLoc());
+  const Decl *refedDecl = getDeclareReferencedDecl(varOperand);
+  StringRef varName = getMangledName(GlobalDecl{cast<VarDecl>(refedDecl)});
+
+  // We have to emit two separate functions in this case, an acc_ctor and an
+  // acc_dtor. These two sections are/should remain reasonably equal, however
+  // the order of the clauses/vs-enter&exit in them makes combining these two
+  // sections not particularly attractive, so we have a bit of repetition.
+  {
+    mlir::OpBuilder::InsertionGuard guardCase(builder);
+    auto ctorOp = mlir::acc::GlobalConstructorOp::create(
+        builder, exprLoc, (varName + "_acc_ctor").str());
+    getModule().push_back(ctorOp);
+    mlir::Block *block = builder.createBlock(&ctorOp.getRegion(),
+                                             ctorOp.getRegion().end(), {}, {});
+    builder.setInsertionPointToEnd(block);
+    // These things are close enough to a function handling-wise we can just
+    // create this here.
+    CIRGenFunction cgf{*this, builder, true};
+    llvm::SaveAndRestore<CIRGenFunction *> savedCGF(curCGF, &cgf);
+    cgf.curFn = ctorOp;
+    CIRGenFunction::SourceLocRAIIObject fnLoc{cgf, exprLoc};
+
+    // This gets the information we need, PLUS emits the bounds correctly, so we
+    // have to do this in both enter and exit.
+    CIRGenFunction::OpenACCDataOperandInfo inf =
+        cgf.getOpenACCDataOperandInfo(varOperand);
+    auto beforeOp =
+        BeforeOpTy::create(builder, exprLoc, inf.varValue, structured, implicit,
+                           inf.name, inf.bounds);
+    beforeOp.setDataClause(dataClause);
+    beforeOp.setModifiers(convertOpenACCModifiers(modifiers));
+
+    mlir::acc::DeclareEnterOp::create(
+        builder, exprLoc, mlir::acc::DeclareTokenType::get(&getMLIRContext()),
+        beforeOp.getResult());
+
+    mlir::acc::TerminatorOp::create(builder, exprLoc);
+  }
+
+  // copyin, create, and device_resident require a destructor, link does not. In
+  // the case of the first three, they are all a 'getdeviceptr', followed by the
+  // declare_exit, followed by a delete op in the destructor region.
+  if (requiresDtor) {
+    mlir::OpBuilder::InsertionGuard guardCase(builder);
+    auto ctorOp = mlir::acc::GlobalDestructorOp::create(
+        builder, exprLoc, (varName + "_acc_dtor").str());
+    getModule().push_back(ctorOp);
+    mlir::Block *block = builder.createBlock(&ctorOp.getRegion(),
+                                             ctorOp.getRegion().end(), {}, {});
+    builder.setInsertionPointToEnd(block);
+
+    // These things are close enough to a function handling-wise we can just
+    // create this here.
+    CIRGenFunction cgf{*this, builder, true};
+    llvm::SaveAndRestore<CIRGenFunction *> savedCGF(curCGF, &cgf);
+    cgf.curFn = ctorOp;
+    CIRGenFunction::SourceLocRAIIObject fnLoc{cgf, exprLoc};
+
+    CIRGenFunction::OpenACCDataOperandInfo inf =
+        cgf.getOpenACCDataOperandInfo(varOperand);
+    auto getDevPtr = mlir::acc::GetDevicePtrOp::create(
+        builder, exprLoc, inf.varValue, structured, implicit, inf.name,
+        inf.bounds);
+    getDevPtr.setDataClause(dataClause);
+    getDevPtr.setModifiers(convertOpenACCModifiers(modifiers));
+
+    mlir::acc::DeclareExitOp::create(builder, exprLoc, /*token=*/mlir::Value{},
+                                     getDevPtr.getResult());
+    auto deleteOp = mlir::acc::DeleteOp::create(
+        builder, exprLoc, getDevPtr, structured, implicit, inf.name, {});
+    deleteOp.setDataClause(dataClause);
+    deleteOp.setModifiers(convertOpenACCModifiers(modifiers));
+    mlir::acc::TerminatorOp::create(builder, exprLoc);
+  }
+}
+namespace {
+// This class emits all of the information for a 'declare' at a global/ns/class
+// scope. Each clause results in its own acc_ctor and acc_dtor for the variable.
+// This class creates those and emits them properly.
+// This behavior is unique/special enough from the emission of statement-level
+// clauses that it doesn't really make sense to use that clause visitor.
+class OpenACCGlobalDeclareClauseEmitter final
+    : public OpenACCClauseVisitor<OpenACCGlobalDeclareClauseEmitter> {
+  CIRGenModule &cgm;
+  void clauseNotImplemented(const OpenACCClause &c) {
+    cgm.errorNYI(c.getSourceRange(), "OpenACC Global Declare Clause",
+                 c.getClauseKind());
+  }
+
+public:
+  OpenACCGlobalDeclareClauseEmitter(CIRGenModule &cgm) : cgm(cgm) {}
+
+  void VisitClause(const OpenACCClause &clause) {
+    clauseNotImplemented(clause);
+  }
+
+  void emitClauses(ArrayRef<const OpenACCClause *> clauses) {
+    this->VisitClauseList(clauses);
+  }
+
+  void VisitCreateClause(const OpenACCCreateClause &clause) {
+    for (const Expr *var : clause.getVarList())
+      cgm.emitGlobalOpenACCDeclareDataOperands<mlir::acc::CreateOp>(
+          var, mlir::acc::DataClause::acc_create, clause.getModifierList(),
+          /*structured=*/true,
+          /*implicit=*/false, /*requiresDtor=*/true);
+  }
+};
+} // namespace
+
+void CIRGenModule::emitGlobalOpenACCDeclareDecl(const OpenACCDeclareDecl *d) {
+  // Declare creates 1 'acc_ctor' and 0-1 'acc_dtor' per clause, since it needs
+  // a unique one on a per-variable basis. We can just use a clause emitter to
+  // do all the work.
+  mlir::OpBuilder::InsertionGuard guardCase(builder);
+  OpenACCGlobalDeclareClauseEmitter em{*this};
+  em.emitClauses(d->clauses());
+}
+
 void CIRGenFunction::emitOpenACCRoutine(const OpenACCRoutineDecl &d) {
   getCIRGenModule().errorNYI(d.getSourceRange(), "OpenACC Routine Construct");
 }
 
-void CIRGenModule::emitGlobalOpenACCDecl(const OpenACCConstructDecl *d) {
-  if (isa<OpenACCRoutineDecl>(d))
-    errorNYI(d->getSourceRange(), "OpenACC Routine Construct");
-  else if (isa<OpenACCDeclareDecl>(d))
-    errorNYI(d->getSourceRange(), "OpenACC Declare Construct");
-  else
-    llvm_unreachable("unknown OpenACC declaration kind?");
+void CIRGenModule::emitGlobalOpenACCRoutineDecl(const OpenACCRoutineDecl *d) {
+  errorNYI(d->getSourceRange(), "OpenACC Global Routine Construct");
 }

clang/lib/CIR/CodeGen/CIRGenModule.cpp

@@ -1513,10 +1513,10 @@ void CIRGenModule::emitTopLevelDecl(Decl *decl) {
     break;
   }
   case Decl::OpenACCRoutine:
-    emitGlobalOpenACCDecl(cast<OpenACCRoutineDecl>(decl));
+    emitGlobalOpenACCRoutineDecl(cast<OpenACCRoutineDecl>(decl));
     break;
   case Decl::OpenACCDeclare:
-    emitGlobalOpenACCDecl(cast<OpenACCDeclareDecl>(decl));
+    emitGlobalOpenACCDeclareDecl(cast<OpenACCDeclareDecl>(decl));
     break;
   case Decl::Enum:
   case Decl::Using:          // using X; [C++]
@@ -1560,7 +1560,7 @@ void CIRGenModule::emitTopLevelDecl(Decl *decl) {
     CXXRecordDecl *crd = cast<CXXRecordDecl>(decl);
     assert(!cir::MissingFeatures::generateDebugInfo());
     for (auto *childDecl : crd->decls())
-      if (isa<VarDecl, CXXRecordDecl, EnumDecl>(childDecl))
+      if (isa<VarDecl, CXXRecordDecl, EnumDecl, OpenACCDeclareDecl>(childDecl))
         emitTopLevelDecl(childDecl);
     break;
   }

clang/lib/CIR/CodeGen/CIRGenModule.h

@@ -453,6 +453,14 @@ class CIRGenModule : public CIRGenTypeCache {
                                     bool performInit);
 
   void emitGlobalOpenACCDecl(const clang::OpenACCConstructDecl *cd);
+  void emitGlobalOpenACCRoutineDecl(const clang::OpenACCRoutineDecl *cd);
+  void emitGlobalOpenACCDeclareDecl(const clang::OpenACCDeclareDecl *cd);
+  template <typename BeforeOpTy, typename DataClauseTy>
+  void emitGlobalOpenACCDeclareDataOperands(const Expr *varOperand,
+                                            DataClauseTy dataClause,
+                                            OpenACCModifierKind modifiers,
+                                            bool structured, bool implicit,
+                                            bool requiresDtor);
 
   // C++ related functions.
   void emitDeclContext(const DeclContext *dc);

clang/lib/CIR/CodeGen/CIRGenOpenACCClause.cpp

@@ -14,6 +14,7 @@
 
 #include "CIRGenCXXABI.h"
 #include "CIRGenFunction.h"
+#include "CIRGenOpenACCHelpers.h"
 #include "CIRGenOpenACCRecipe.h"
 
 #include "clang/AST/ExprCXX.h"
@@ -182,33 +183,6 @@ class OpenACCClauseCIREmitter final
     dataOperands.append(computeEmitter.dataOperands);
   }
 
-  mlir::acc::DataClauseModifier
-  convertModifiers(OpenACCModifierKind modifiers) {
-    using namespace mlir::acc;
-    static_assert(static_cast<int>(OpenACCModifierKind::Zero) ==
-                      static_cast<int>(DataClauseModifier::zero) &&
-                  static_cast<int>(OpenACCModifierKind::Readonly) ==
-                      static_cast<int>(DataClauseModifier::readonly) &&
-                  static_cast<int>(OpenACCModifierKind::AlwaysIn) ==
-                      static_cast<int>(DataClauseModifier::alwaysin) &&
-                  static_cast<int>(OpenACCModifierKind::AlwaysOut) ==
-                      static_cast<int>(DataClauseModifier::alwaysout) &&
-                  static_cast<int>(OpenACCModifierKind::Capture) ==
-                      static_cast<int>(DataClauseModifier::capture));
-
-    DataClauseModifier mlirModifiers{};
-
-    // The MLIR representation of this represents `always` as `alwaysin` +
-    // `alwaysout`.  So do a small fixup here.
-    if (isOpenACCModifierBitSet(modifiers, OpenACCModifierKind::Always)) {
-      mlirModifiers = mlirModifiers | DataClauseModifier::always;
-      modifiers &= ~OpenACCModifierKind::Always;
-    }
-
-    mlirModifiers = mlirModifiers | static_cast<DataClauseModifier>(modifiers);
-    return mlirModifiers;
-  }
-
   template <typename BeforeOpTy, typename AfterOpTy>
   void addDataOperand(const Expr *varOperand, mlir::acc::DataClause dataClause,
                       OpenACCModifierKind modifiers, bool structured,
@@ -243,8 +217,8 @@ class OpenACCClauseCIREmitter final
     // Set the 'rest' of the info for both operations.
     beforeOp.setDataClause(dataClause);
     afterOp.setDataClause(dataClause);
-    beforeOp.setModifiers(convertModifiers(modifiers));
-    afterOp.setModifiers(convertModifiers(modifiers));
+    beforeOp.setModifiers(convertOpenACCModifiers(modifiers));
+    afterOp.setModifiers(convertOpenACCModifiers(modifiers));
 
     // Make sure we record these, so 'async' values can be updated later.
     dataOperands.push_back(beforeOp.getOperation());
@@ -264,7 +238,7 @@ class OpenACCClauseCIREmitter final
 
     // Set the 'rest' of the info for the operation.
     beforeOp.setDataClause(dataClause);
-    beforeOp.setModifiers(convertModifiers(modifiers));
+    beforeOp.setModifiers(convertOpenACCModifiers(modifiers));
 
     // Make sure we record these, so 'async' values can be updated later.
     dataOperands.push_back(beforeOp.getOperation());

clang/lib/CIR/CodeGen/CIRGenOpenACCHelpers.h

@@ -0,0 +1,43 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This contains helpers for OpenACC emission that don't need to be in
+// CIRGenModule, but can't live in a single .cpp file.
+//
+//===----------------------------------------------------------------------===//
+#include "mlir/Dialect/OpenACC/OpenACC.h"
+#include "clang/AST/DeclOpenACC.h"
+
+namespace clang::CIRGen {
+inline mlir::acc::DataClauseModifier
+convertOpenACCModifiers(OpenACCModifierKind modifiers) {
+  using namespace mlir::acc;
+  static_assert(static_cast<int>(OpenACCModifierKind::Zero) ==
+                    static_cast<int>(DataClauseModifier::zero) &&
+                static_cast<int>(OpenACCModifierKind::Readonly) ==
+                    static_cast<int>(DataClauseModifier::readonly) &&
+                static_cast<int>(OpenACCModifierKind::AlwaysIn) ==
+                    static_cast<int>(DataClauseModifier::alwaysin) &&
+                static_cast<int>(OpenACCModifierKind::AlwaysOut) ==
+                    static_cast<int>(DataClauseModifier::alwaysout) &&
+                static_cast<int>(OpenACCModifierKind::Capture) ==
+                    static_cast<int>(DataClauseModifier::capture));
+
+  DataClauseModifier mlirModifiers{};
+
+  // The MLIR representation of this represents `always` as `alwaysin` +
+  // `alwaysout`.  So do a small fixup here.
+  if (isOpenACCModifierBitSet(modifiers, OpenACCModifierKind::Always)) {
+    mlirModifiers = mlirModifiers | DataClauseModifier::always;
+    modifiers &= ~OpenACCModifierKind::Always;
+  }
+
+  mlirModifiers = mlirModifiers | static_cast<DataClauseModifier>(modifiers);
+  return mlirModifiers;
+}
+} // namespace clang::CIRGen