[flang-commits] [flang] [flang] Implement !DIR$ IVDEP directive (PR #133728)

[Kiran Chandramohan via flang-commits]

================
@@ -2046,6 +2046,37 @@ class FirConverter : public Fortran::lower::AbstractConverter {
     // so no clean-up needs to be generated for these entities.
   }
 
+  // Add attribute(s) on operations in fir::DoLoopOp if necessary.
+  void attachAttributesToDoLoopOperations(fir::DoLoopOp &doLoop) {
+    if (!doLoop.getOperation())
+      return;
+    if (auto loopAnnotAttr = doLoop.getLoopAnnotationAttr()) {
+      if (loopAnnotAttr.getParallelAccesses().size()) {
+        mlir::LLVM::AccessGroupAttr accessGroupAttr =
+            loopAnnotAttr.getParallelAccesses().front();
+        for (mlir::Block &block : doLoop.getRegion()) {
+          mlir::ArrayAttr attrs =
+              mlir::ArrayAttr::get(builder->getContext(), {accessGroupAttr});
+          for (mlir::Operation &op : block.getOperations()) {
+            if (fir::StoreOp storeOp = mlir::dyn_cast<fir::StoreOp>(op)) {
+              storeOp.setAccessGroupsAttr(attrs);
+            } else if (fir::LoadOp loadOp = mlir::dyn_cast<fir::LoadOp>(op)) {
+              loadOp.setAccessGroupsAttr(attrs);
+            } else if (hlfir::AssignOp assignOp =
+                           mlir::dyn_cast<hlfir::AssignOp>(op)) {
+              // In some loops, the HLFIR AssignOp operation can be translated
+              // into FIR operation(s) containing StoreOp. It is therefore
+              // necessary to forward the AccessGroups attribute.
+              assignOp.getOperation()->setAttr("access_groups", attrs);
+            } else if (fir::CallOp callOp = mlir::dyn_cast<fir::CallOp>(op)) {
+              callOp.setAccessGroupsAttr(attrs);
+            }
+          }
+        }
+      }
+    }
+  }
----------------
kiranchandramohan wrote:

Do we need to go into operations that are nested inside other operations?

```
subroutine sb(A)
  integer, intent(inout) :: A(:)
  integer :: i
  !dir$ ivdep
  do i=1,100
    if (i .gt. 10) then
      A(i) = A(i) + i
    end if 
  end do
end subroutine
```

https://github.com/llvm/llvm-project/pull/133728