[Mlir-commits] [mlir] [mlir][ArmSME] Add a tests showing liveness issues in the tile allocator (PR #90447)

[Andrzej Warzyński]

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@@ -0,0 +1,328 @@
+// RUN: mlir-opt %s -allocate-arm-sme-tiles -split-input-file -verify-diagnostics | FileCheck %s --check-prefix=CHECK-BAD
+
+// This file tests some aspects of liveness issues in the SME tile allocator.
+// These tests were designed with a new liveness-based tile allocator in mind,
+// with the current tile allocator these tests all give incorrect results (which
+// is documented by `CHECK-BAD`).
+//
+// Currently only the `CHECK-BAD` tests are run (as the new liveness based
+// allocator is not yet available -- so all other tests fail).
+
+//       CHECK-LIVE-RANGE: ========== Coalesced Live Ranges:
+//  CHECK-LIVE-RANGE-NEXT: @constant_with_multiple_users
+//       CHECK-LIVE-RANGE: ^bb0:
+//       CHECK-LIVE-RANGE: S  arm_sme.zero
+//  CHECK-LIVE-RANGE-NEXT: |S arm_sme.move_vector_to_tile_slice
+//  CHECK-LIVE-RANGE-NEXT: || arm_sme.move_vector_to_tile_slice
+//  CHECK-LIVE-RANGE-NEXT: |E test.some_use
+//  CHECK-LIVE-RANGE-NEXT: E  test.some_use
+
+// Incorrect result! The second `move_vector_to_tile_slice` overwrites the first (which is still live).
+//
+// CHECK-BAD-LABEL: @constant_with_multiple_users(
+// CHECK-BAD-SAME:                                %[[VECTOR_A:.*]]: vector<[4]xf32>, %[[VECTOR_B:.*]]: vector<[4]xf32>
+// CHECK-BAD: %[[ZERO_TILE:.*]] = arm_sme.zero {tile_id = 0 : i32} : vector<[4]x[4]xf32>
+// CHECK-BAD: %[[INSERT_TILE_1:.*]] = arm_sme.move_vector_to_tile_slice %[[VECTOR_A]], %[[ZERO_TILE]], %{{.*}} {tile_id = 0 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
+// CHECK-BAD: %[[INSERT_TILE_0:.*]] = arm_sme.move_vector_to_tile_slice %[[VECTOR_B]], %[[ZERO_TILE]], %{{.*}} {tile_id = 0 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
+
+// CHECK-LABEL: @constant_with_multiple_users(
+// CHECK-SAME:                                %[[VECTOR_A:.*]]: vector<[4]xf32>, %[[VECTOR_B:.*]]: vector<[4]xf32>
+func.func @constant_with_multiple_users(%a: vector<[4]xf32>, %b: vector<[4]xf32>, %index: index) {
+  // CHECK-NEXT: %[[ZERO_TILE_0:.*]] = arm_sme.zero {tile_id = 0 : i32} : vector<[4]x[4]xf32>
+  // CHECK-NEXT: %[[ZERO_TILE_1:.*]] = arm_sme.zero {tile_id = 1 : i32} : vector<[4]x[4]xf32>
+  // CHECK-NEXT: %[[INSERT_TILE_1:.*]] = arm_sme.move_vector_to_tile_slice %[[VECTOR_A]], %[[ZERO_TILE_1]], %{{.*}} {tile_id = 1 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
+  // CHECK-NEXT: %[[INSERT_TILE_0:.*]] = arm_sme.move_vector_to_tile_slice %[[VECTOR_B]], %[[ZERO_TILE_0]], %{{.*}} {tile_id = 0 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
+  %zero = arm_sme.zero : vector<[4]x[4]xf32>
+  %tile_a = arm_sme.move_vector_to_tile_slice %a, %zero, %index : vector<[4]xf32> into vector<[4]x[4]xf32>
+  %tile_b = arm_sme.move_vector_to_tile_slice %b, %zero, %index : vector<[4]xf32> into vector<[4]x[4]xf32>
+  "test.some_use"(%tile_a) : (vector<[4]x[4]xf32>) -> ()
+  "test.some_use"(%tile_b) : (vector<[4]x[4]xf32>) -> ()
+  return
+}
+
+// -----
+
+//       CHECK-LIVE-RANGE: ========== Coalesced Live Ranges:
+//  CHECK-LIVE-RANGE-NEXT: @value_with_multiple_users
+//       CHECK-LIVE-RANGE: ^bb0:
+//  CHECK-LIVE-RANGE-NEXT: |S arm_sme.move_vector_to_tile_slice
+//  CHECK-LIVE-RANGE-NEXT: || arm_sme.move_vector_to_tile_slice
+//  CHECK-LIVE-RANGE-NEXT: |E test.some_use
+//  CHECK-LIVE-RANGE-NEXT: E  test.some_use
+
+// (No CHECK-BAD -- the current tile allocator ignores this case)
----------------
banach-space wrote:

Could you add `CHECK-NOT: tile_id = `?

https://github.com/llvm/llvm-project/pull/90447