[flang][openacc] Make implicit declare region unstructured (#71591)

Using an op with a region cause some issue with unstructured code. This
patch make use of acc.declare_enter and acc.declare_exit to represent
the implicit declare region.

1 files changed, 7 insertions, 1 deletions

diff --git a/flang/lib/Lower/Bridge.cpp b/flang/lib/Lower/Bridge.cpp
index 59906c6..872bf6b 100644
--- a/flang/lib/Lower/Bridge.cpp
+++ b/flang/lib/Lower/Bridge.cpp
@@ -1431,6 +1431,7 @@ private:
             resultRef = builder->createConvert(loc, resultRefType, resultRef);
           return builder->create<fir::LoadOp>(loc, resultRef);
         });
+    bridge.openAccCtx().finalizeAndPop();
     bridge.fctCtx().finalizeAndPop();
     builder->create<mlir::func::ReturnOp>(loc, resultVal);
   }
@@ -1458,9 +1459,11 @@ private:
     } else if (Fortran::semantics::HasAlternateReturns(symbol)) {
       mlir::Value retval = builder->create<fir::LoadOp>(
           toLocation(), getAltReturnResult(symbol));
+      bridge.openAccCtx().finalizeAndPop();
       bridge.fctCtx().finalizeAndPop();
       builder->create<mlir::func::ReturnOp>(toLocation(), retval);
     } else {
+      bridge.openAccCtx().finalizeAndPop();
       bridge.fctCtx().finalizeAndPop();
       genExitRoutine();
     }
@@ -2388,7 +2391,8 @@ private:
 
   void genFIR(const Fortran::parser::OpenACCDeclarativeConstruct &accDecl) {
     genOpenACCDeclarativeConstruct(*this, bridge.getSemanticsContext(),
-                                   bridge.fctCtx(), accDecl, accRoutineInfos);
+                                   bridge.openAccCtx(), accDecl,
+                                   accRoutineInfos);
     for (Fortran::lower::pft::Evaluation &e : getEval().getNestedEvaluations())
       genFIR(e);
   }
@@ -4204,6 +4208,7 @@ private:
   void startNewFunction(Fortran::lower::pft::FunctionLikeUnit &funit) {
     assert(!builder && "expected nullptr");
     bridge.fctCtx().pushScope();
+    bridge.openAccCtx().pushScope();
     const Fortran::semantics::Scope &scope = funit.getScope();
     LLVM_DEBUG(llvm::dbgs() << "\n[bridge - startNewFunction]";
                if (auto *sym = scope.symbol()) llvm::dbgs() << " " << *sym;
@@ -4444,6 +4449,7 @@ private:
   void endNewFunction(Fortran::lower::pft::FunctionLikeUnit &funit) {
     setCurrentPosition(Fortran::lower::pft::stmtSourceLoc(funit.endStmt));
     if (funit.isMainProgram()) {
+      bridge.openAccCtx().finalizeAndPop();
       bridge.fctCtx().finalizeAndPop();
       genExitRoutine();
     } else {