[Mlir-commits] [mlir] [MLIR] getBackwardSlice: don't bail on ops that are IsolatedFromAbove (PR #158135)

[Ian Wood]

https://github.com/IanWood1 updated https://github.com/llvm/llvm-project/pull/158135

>From aa4b2a1fb06f80585ccfe0fcbbc4ca1095e5da36 Mon Sep 17 00:00:00 2001
From: Ian Wood <ianwood at u.northwestern.edu>
Date: Thu, 11 Sep 2025 18:58:36 +0000
Subject: [PATCH 1/2] [MLIR] getBackwardSlice: don't bail on ops that are
 IsolatedFromAbove

Signed-off-by: Ian Wood <ianwood at u.northwestern.edu>
---
 mlir/lib/Analysis/SliceAnalysis.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mlir/lib/Analysis/SliceAnalysis.cpp b/mlir/lib/Analysis/SliceAnalysis.cpp
index 7037fa644c7be..d0e10626589ce 100644
--- a/mlir/lib/Analysis/SliceAnalysis.cpp
+++ b/mlir/lib/Analysis/SliceAnalysis.cpp
@@ -109,7 +109,7 @@ static LogicalResult getBackwardSliceImpl(Operation *op,
                                           DenseSet<Operation *> &visited,
                                           SetVector<Operation *> *backwardSlice,
                                           const BackwardSliceOptions &options) {
-  if (!op || op->hasTrait<OpTrait::IsIsolatedFromAbove>())
+  if (!op)
     return success();
 
   // Evaluate whether we should keep this def.

>From fb257b221e57d208103a62b98f30a277ced4450f Mon Sep 17 00:00:00 2001
From: Ian Wood <ianwood at u.northwestern.edu>
Date: Fri, 12 Sep 2025 20:21:54 +0000
Subject: [PATCH 2/2] Add test

Signed-off-by: Ian Wood <ianwood at u.northwestern.edu>
---
 mlir/test/Transforms/move-operation-deps.mlir | 28 +++++++++++++++++++
 mlir/test/lib/Dialect/Test/TestOps.td         |  3 +-
 .../Transforms/TestMakeIsolatedFromAbove.cpp  |  4 +--
 3 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/mlir/test/Transforms/move-operation-deps.mlir b/mlir/test/Transforms/move-operation-deps.mlir
index aa7b5dc2a240a..75d8386d520ee 100644
--- a/mlir/test/Transforms/move-operation-deps.mlir
+++ b/mlir/test/Transforms/move-operation-deps.mlir
@@ -460,3 +460,31 @@ module attributes {transform.with_named_sequence} {
     transform.yield
   }
 }
+
+// -----
+
+func.func @move_isolated_from_above() -> () {
+  %1 = "before"() : () -> (f32)
+  %2 = "moved0"() : () -> (f32)
+  %3 = test.isolated_one_region_op %2 {} : f32 -> f32
+  %4 = "moved1"(%3) : (f32) -> (f32)
+  return
+}
+// CHECK-LABEL: func @move_isolated_from_above()
+//       CHECK:   %[[MOVED0:.+]] = "moved0"
+//       CHECK:   %[[ISOLATED:.+]] = test.isolated_one_region_op %[[MOVED0]]
+//       CHECK:   %[[MOVED1:.+]] = "moved1"(%[[ISOLATED]])
+//       CHECK:   %[[BEFORE:.+]] = "before"
+
+module attributes {transform.with_named_sequence} {
+  transform.named_sequence @__transform_main(%arg0 : !transform.any_op {transform.readonly}) {
+    %op1 = transform.structured.match ops{["before"]} in %arg0
+        : (!transform.any_op) -> !transform.any_op
+    %op2 = transform.structured.match ops{["moved1"]} in %arg0
+        : (!transform.any_op) -> !transform.any_op
+    %v1 = transform.get_result %op2[0] : (!transform.any_op) -> !transform.any_value
+    transform.test.move_value_defns %v1 before %op1
+        : (!transform.any_value), !transform.any_op
+    transform.yield
+  }
+}
diff --git a/mlir/test/lib/Dialect/Test/TestOps.td b/mlir/test/lib/Dialect/Test/TestOps.td
index 5564264ed8b0b..d9bbb3261febc 100644
--- a/mlir/test/lib/Dialect/Test/TestOps.td
+++ b/mlir/test/lib/Dialect/Test/TestOps.td
@@ -552,9 +552,10 @@ def OneRegionWithOperandsOp : TEST_Op<"one_region_with_operands_op", []> {
 
 def IsolatedOneRegionOp : TEST_Op<"isolated_one_region_op", [IsolatedFromAbove]> {
   let arguments = (ins Variadic<AnyType>:$operands);
+  let results = (outs Variadic<AnyType>:$results);
   let regions = (region AnyRegion:$my_region);
   let assemblyFormat = [{
-    attr-dict-with-keyword $operands $my_region `:` type($operands)
+    attr-dict-with-keyword $operands $my_region `:` type($operands) `->` type($results)
   }];
 }
 
diff --git a/mlir/test/lib/Transforms/TestMakeIsolatedFromAbove.cpp b/mlir/test/lib/Transforms/TestMakeIsolatedFromAbove.cpp
index c1fb70605ab46..f7bde79274e91 100644
--- a/mlir/test/lib/Transforms/TestMakeIsolatedFromAbove.cpp
+++ b/mlir/test/lib/Transforms/TestMakeIsolatedFromAbove.cpp
@@ -27,8 +27,8 @@ makeIsolatedFromAboveImpl(RewriterBase &rewriter,
       makeRegionIsolatedFromAbove(rewriter, region, callBack);
   SmallVector<Value> operands = regionOp.getOperands();
   operands.append(capturedValues);
-  auto isolatedRegionOp =
-      test::IsolatedOneRegionOp::create(rewriter, regionOp.getLoc(), operands);
+  auto isolatedRegionOp = test::IsolatedOneRegionOp::create(
+      rewriter, regionOp.getLoc(), TypeRange(), operands);
   rewriter.inlineRegionBefore(region, isolatedRegionOp.getRegion(),
                               isolatedRegionOp.getRegion().begin());
   rewriter.eraseOp(regionOp);