[flang] Added basic connect to lower OpenMP constructs

[clementval]

Can you lower a small construct with that so we can have a test?

[shraiysh]

Added testcase.

[shraiysh]

Added missing newline at the end of file. Ready for review now.

[clementval]

Maybe I'm missing something but where is the create<mlir::omp::BarrierOp>?

[shraiysh]

In D121382#3372933, @clementval wrote:

Maybe I'm missing something but where is the create<mlir::omp::BarrierOp>?

Here it is. It was upstreamed over an year ago :) - https://github.com/llvm/llvm-project/blob/58966dd42bc4af67ff6b580a8cc3d36abba98add/flang/lib/Lower/OpenMP.cpp#L77

[clementval]

In D121382#3372966, @shraiysh wrote:

In D121382#3372933, @clementval wrote:

Maybe I'm missing something but where is the create<mlir::omp::BarrierOp>?

Here it is. It was upstreamed over an year ago :) - https://github.com/llvm/llvm-project/blob/58966dd42bc4af67ff6b580a8cc3d36abba98add/flang/lib/Lower/OpenMP.cpp#L77

My bad :-)

[clementval]

LGTM

flang/lib/Lower/Bridge.cpp

 #include "flang/Lower/Allocatable.h"
 #include "flang/Lower/CallInterface.h"
 #include "flang/Lower/ConvertExpr.h"
 #include "flang/Lower/ConvertType.h"
 #include "flang/Lower/ConvertVariable.h"
 #include "flang/Lower/IO.h"
 #include "flang/Lower/IterationSpace.h"
 #include "flang/Lower/Mangler.h"
+#include "flang/Lower/OpenMP.h"
 #include "flang/Lower/PFTBuilder.h"
 #include "flang/Lower/Runtime.h"
 #include "flang/Lower/StatementContext.h"
 #include "flang/Lower/SymbolMap.h"
 #include "flang/Lower/Todo.h"
 #include "flang/Optimizer/Builder/BoxValue.h"
 #include "flang/Optimizer/Builder/Character.h"
 #include "flang/Optimizer/Builder/MutableBox.h"
private:
   void genFIR(const Fortran::parser::OpenACCConstruct &) {
     TODO(toLocation(), "OpenACCConstruct lowering");
   }
 
   void genFIR(const Fortran::parser::OpenACCDeclarativeConstruct &) {
     TODO(toLocation(), "OpenACCDeclarativeConstruct lowering");
   }
 
-  void genFIR(const Fortran::parser::OpenMPConstruct &) {
-    TODO(toLocation(), "OpenMPConstruct lowering");
+  void genFIR(const Fortran::parser::OpenMPConstruct &omp) {
+    mlir::OpBuilder::InsertPoint insertPt = builder->saveInsertionPoint();
+    localSymbols.pushScope();
+    Fortran::lower::genOpenMPConstruct(*this, getEval(), omp);
+
+    for (Fortran::lower::pft::Evaluation &e : getEval().getNestedEvaluations())
+      genFIR(e);
+    localSymbols.popScope();
+    builder->restoreInsertionPoint(insertPt);
   }
 
   void genFIR(const Fortran::parser::OpenMPDeclarativeConstruct &) {
     TODO(toLocation(), "OpenMPDeclarativeConstruct lowering");
   }
 
   void genFIR(const Fortran::parser::SelectCaseStmt &) {
     TODO(toLocation(), "SelectCaseStmt lowering");

flang/test/Lower/OpenMP/simple-barrier.f90

+! RUN: bbc -fopenmp -emit-fir -o - %s | FileCheck %s
+
+subroutine sample()
+! CHECK: omp.barrier
+!$omp barrier
+end subroutine sample