[Mlir-commits] [mlir] [MLIR] Add ReturnLike trait to memref.atomic_yield (PR #144932)

[Mehdi Amini]

https://github.com/joker-eph created https://github.com/llvm/llvm-project/pull/144932

Without this, the yield isn't considered as the region terminator and the dataflow framework does not consider it live.

>From 3c397ccc1953bdaadaf22e4f16cdea5403ebecd6 Mon Sep 17 00:00:00 2001
From: Mehdi Amini <joker.eph at gmail.com>
Date: Thu, 19 Jun 2025 10:40:09 -0700
Subject: [PATCH] [MLIR] Add ReturnLike trait to memref.atomic_yield

Without this, the yield isn't considered as the region terminator and
the dataflow framework does not consider it live.
---
 mlir/include/mlir/Dialect/MemRef/IR/MemRefOps.td |  3 +--
 mlir/test/Transforms/remove-dead-values.mlir     | 15 +++++++++++++++
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/mlir/include/mlir/Dialect/MemRef/IR/MemRefOps.td b/mlir/include/mlir/Dialect/MemRef/IR/MemRefOps.td
index 77e3074661abf..fe3b7a80c3dea 100644
--- a/mlir/include/mlir/Dialect/MemRef/IR/MemRefOps.td
+++ b/mlir/include/mlir/Dialect/MemRef/IR/MemRefOps.td
@@ -1078,8 +1078,7 @@ def GenericAtomicRMWOp : MemRef_Op<"generic_atomic_rmw", [
 
 def AtomicYieldOp : MemRef_Op<"atomic_yield", [
       HasParent<"GenericAtomicRMWOp">,
-      Pure,
-      Terminator
+      Pure, Terminator, ReturnLike
     ]> {
   let summary = "yield operation for GenericAtomicRMWOp";
   let description = [{
diff --git a/mlir/test/Transforms/remove-dead-values.mlir b/mlir/test/Transforms/remove-dead-values.mlir
index 8c2a1cf7546f3..631b507c993e4 100644
--- a/mlir/test/Transforms/remove-dead-values.mlir
+++ b/mlir/test/Transforms/remove-dead-values.mlir
@@ -510,3 +510,18 @@ module {
 // CHECK: %[[yield:.*]] = arith.addf %{{.*}}, %{{.*}} : f32
 // CHECK: linalg.yield %[[yield]] : f32
 // CHECK-NOT: arith.subf
+
+// -----
+
+// CHECK-LABEL: func.func @test_atomic_yield
+func.func @test_atomic_yield(%I: memref<10xf32>, %idx : index) {
+  // CHECK: memref.generic_atomic_rmw
+  %x = memref.generic_atomic_rmw %I[%idx] : memref<10xf32> {
+  ^bb0(%current_value : f32):
+  // CHECK: arith.constant
+    %c1 = arith.constant 1.0 : f32
+  // CHECK: memref.atomic_yield
+    memref.atomic_yield %c1 : f32
+  }
+  func.return
+}