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

[Benjamin Maxwell]

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+// 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
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MacDue wrote:

I find the check live range tests quite helpful in understanding the incorrect results (as you can see from looking at the live ranges why two values should not be assigned to the same tile ID). Things that overlap in liveness can't go to the same tile ID.  

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