[Mlir-commits] [mlir] 370a571 - [RegionUtils] replace uses in nested regions when isolating from above (#180548)

[llvmlistbot at llvm.org]

Author: Scott Manley
Date: 2026-02-10T07:36:47-06:00
New Revision: 370a571597883c8e251568f1e4ef046fe61eedc6

URL: https://github.com/llvm/llvm-project/commit/370a571597883c8e251568f1e4ef046fe61eedc6
DIFF: https://github.com/llvm/llvm-project/commit/370a571597883c8e251568f1e4ef046fe61eedc6.diff

LOG: [RegionUtils] replace uses in nested regions when isolating from above (#180548)

When making a region IsolatedFromAbove, replace uses in any region
within the parent region, not just the immediate parent region.

Added: 
    

Modified: 
    mlir/lib/Transforms/Utils/RegionUtils.cpp
    mlir/test/Transforms/make-isolated-from-above.mlir

Removed: 
    


################################################################################
diff  --git a/mlir/lib/Transforms/Utils/RegionUtils.cpp b/mlir/lib/Transforms/Utils/RegionUtils.cpp
index 5406a51d2ab7f..a87cb15625130 100644
--- a/mlir/lib/Transforms/Utils/RegionUtils.cpp
+++ b/mlir/lib/Transforms/Utils/RegionUtils.cpp
@@ -157,8 +157,9 @@ SmallVector<Value> mlir::makeRegionIsolatedFromAbove(
   // Create a mapping between the captured values and the new arguments added.
   IRMapping map;
   auto replaceIfFn = [&](OpOperand &use) {
-    return use.getOwner()->getBlock()->getParent() == ®ion;
+    return region.isAncestor(use.getOwner()->getParentRegion());
   };
+
   for (auto [arg, capturedVal] :
        llvm::zip(newEntryBlockArgs.take_back(finalCapturedValues.size()),
                  finalCapturedValues)) {

diff  --git a/mlir/test/Transforms/make-isolated-from-above.mlir b/mlir/test/Transforms/make-isolated-from-above.mlir
index a9d4325944fd9..3b0084d6e0007 100644
--- a/mlir/test/Transforms/make-isolated-from-above.mlir
+++ b/mlir/test/Transforms/make-isolated-from-above.mlir
@@ -113,3 +113,28 @@ func.func @make_isolated_from_above_multiple_blocks(%arg0 : index, %arg1 : index
 //  CLONE2-NEXT:       cf.br ^bb1
 //       CLONE2:     ^bb1:
 //       CLONE2:       "foo.yield"(%[[C0]], %[[C1]], %[[D0]], %[[D1]], %[[B0]])
+
+
+// -----
+
+// CHECK-LABEL: func @make_isolated_from_above_nested_region
+//  CHECK-SAME:     %[[ARG0:[a-zA-Z0-9]+]]: memref<8xindex>
+//       CHECK:   %[[C1:.+]] = arith.constant 1 : index
+//       CHECK:   %[[C8:.+]] = arith.constant 8 : index
+//       CHECK:   test.isolated_one_region_op %[[C1]], %[[ARG0]], %[[C8]]
+//       CHECK:   ^bb0(%[[B0:[a-zA-Z0-9]+]]: index, %[[B1:[a-zA-Z0-9]+]]: memref<8xindex>, %[[B2:[a-zA-Z0-9]+]]: index)
+//       CHECK:     scf.for %arg4 = %[[B0]] to %[[B2]] step %[[B0]]
+//       CHECK:       memref.store %[[B0]], %[[B1]][%arg4] : memref<8xindex>
+//       CHECK:     "foo.yield"() : () -> ()
+
+func.func @make_isolated_from_above_nested_region(%arg0 : memref<8xindex>) {
+  %c1 = arith.constant 1 : index
+  %c8 = arith.constant 8 : index
+  "test.one_region_with_operands_op"() ({
+    scf.for %arg1 = %c1 to %c8 step %c1 {
+      memref.store %c1, %arg0[%arg1] : memref<8xindex>
+    }
+    "foo.yield"() : () -> ()
+  }) : () -> ()
+  return
+}