[Mlir-commits] [mlir] [mlir][ArmSME] Add a tests showing liveness issues in the tile allocator (PR #90447)
Benjamin Maxwell
llvmlistbot at llvm.org
Wed May 1 05:55:47 PDT 2024
https://github.com/MacDue updated https://github.com/llvm/llvm-project/pull/90447
>From 32989461e7287d2d055eebba8ddc45868bca1c7d Mon Sep 17 00:00:00 2001
From: Benjamin Maxwell <benjamin.maxwell at arm.com>
Date: Fri, 26 Apr 2024 15:09:20 +0000
Subject: [PATCH 1/4] [mlir][ArmSME] Add a tests showing liveness issues in the
tile allocator
This test shows a few cases (not at all complete) where the current
ArmSME tile allocator produces incorrect results. The plan is to
resolve these issues with a future tile allocator that uses liveness
information.
---
.../ArmSME/tile-allocation-liveness.mlir | 272 ++++++++++++++++++
1 file changed, 272 insertions(+)
create mode 100644 mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir
diff --git a/mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir b/mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir
new file mode 100644
index 00000000000000..e7ca77f08ecc3f
--- /dev/null
+++ b/mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir
@@ -0,0 +1,272 @@
+// RUN: mlir-opt %s -allocate-arm-sme-tiles -split-input-file -verify-diagnostics | FileCheck %s
+
+// This file tests some simple aspects of using liveness in the SME tile allocator.
+
+// Note: This is an XFAIL the new allocator is not yet upstream, and the current
+// allocator gives incorrect results for these tests.
+// XFAIL: *
+
+// 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
+
+// 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
+
+func.func @value_with_multiple_users(%tile: vector<[4]x[4]xf32>, %a: vector<[4]xf32>, %b: vector<[4]xf32>, %index: index) {
+ // expected-error at below {{op failed to rectify tile operand with tile result (move required)}}
+ %tile_a = arm_sme.move_vector_to_tile_slice %a, %tile, %index : vector<[4]xf32> into vector<[4]x[4]xf32>
+ %tile_b = arm_sme.move_vector_to_tile_slice %b, %tile, %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: @reuse_tiles_after_initial_use
+// CHECK-LIVE-RANGE: ^bb0:
+// CHECK-LIVE-RANGE-NEXT: S arm_sme.get_tile
+// CHECK-LIVE-RANGE-NEXT: |S arm_sme.get_tile
+// CHECK-LIVE-RANGE-NEXT: ||S arm_sme.get_tile
+// CHECK-LIVE-RANGE-NEXT: |||S arm_sme.get_tile
+// CHECK-LIVE-RANGE-NEXT: |||| test.dummy
+// CHECK-LIVE-RANGE-NEXT: |||| test.dummy
+// CHECK-LIVE-RANGE-NEXT: |||| test.dummy
+// CHECK-LIVE-RANGE-NEXT: E||| test.some_use
+// CHECK-LIVE-RANGE-NEXT: E|| test.some_use
+// CHECK-LIVE-RANGE-NEXT: E| test.some_use
+// CHECK-LIVE-RANGE-NEXT: E test.some_use
+// CHECK-LIVE-RANGE-NEXT: S arm_sme.zero
+// CHECK-LIVE-RANGE-NEXT: |S arm_sme.zero
+// CHECK-LIVE-RANGE-NEXT: ||S arm_sme.zero
+// CHECK-LIVE-RANGE-NEXT: |||S arm_sme.zero
+// CHECK-LIVE-RANGE-NEXT: |||| test.dummy
+// CHECK-LIVE-RANGE-NEXT: |||| test.dummy
+// CHECK-LIVE-RANGE-NEXT: |||| test.dummy
+// CHECK-LIVE-RANGE-NEXT: E||| test.some_use
+// CHECK-LIVE-RANGE-NEXT: E|| test.some_use
+// CHECK-LIVE-RANGE-NEXT: E| test.some_use
+// CHECK-LIVE-RANGE-NEXT: E test.some_use
+
+// CHECK-LABEL: @reuse_tiles_after_initial_use
+func.func @reuse_tiles_after_initial_use() {
+ // CHECK: arm_sme.get_tile {tile_id = 0 : i32}
+ // CHECK: arm_sme.get_tile {tile_id = 1 : i32}
+ // CHECK: arm_sme.get_tile {tile_id = 2 : i32}
+ // CHECK: arm_sme.get_tile {tile_id = 3 : i32}
+ %tile_a = arm_sme.get_tile : vector<[4]x[4]xf32>
+ %tile_b = arm_sme.get_tile : vector<[4]x[4]xf32>
+ %tile_c = arm_sme.get_tile : vector<[4]x[4]xf32>
+ %tile_d = arm_sme.get_tile : vector<[4]x[4]xf32>
+ "test.dummy"(): () -> ()
+ "test.dummy"(): () -> ()
+ "test.dummy"(): () -> ()
+ "test.some_use"(%tile_a) : (vector<[4]x[4]xf32>) -> ()
+ "test.some_use"(%tile_b) : (vector<[4]x[4]xf32>) -> ()
+ "test.some_use"(%tile_c) : (vector<[4]x[4]xf32>) -> ()
+ "test.some_use"(%tile_d) : (vector<[4]x[4]xf32>) -> ()
+ // CHECK: arm_sme.zero {tile_id = 0 : i32}
+ // CHECK: arm_sme.zero {tile_id = 1 : i32}
+ // CHECK: arm_sme.zero {tile_id = 2 : i32}
+ // CHECK: arm_sme.zero {tile_id = 3 : i32}
+ %tile_1 = arm_sme.zero : vector<[4]x[4]xf32>
+ %tile_2 = arm_sme.zero : vector<[4]x[4]xf32>
+ %tile_3 = arm_sme.zero : vector<[4]x[4]xf32>
+ %tile_4 = arm_sme.zero : vector<[4]x[4]xf32>
+ "test.dummy"(): () -> ()
+ "test.dummy"(): () -> ()
+ "test.dummy"(): () -> ()
+ "test.some_use"(%tile_1) : (vector<[4]x[4]xf32>) -> ()
+ "test.some_use"(%tile_2) : (vector<[4]x[4]xf32>) -> ()
+ "test.some_use"(%tile_3) : (vector<[4]x[4]xf32>) -> ()
+ "test.some_use"(%tile_4) : (vector<[4]x[4]xf32>) -> ()
+ return
+}
+
+// -----
+
+// CHECK-LIVE-RANGE: ========== Coalesced Live Ranges:
+// CHECK-LIVE-RANGE-NEXT: @non_overlapping_branches
+// CHECK-LIVE-RANGE: ^bb1:
+// CHECK-LIVE-RANGE-NEXT: S arm_sme.zero
+// CHECK-LIVE-RANGE-NEXT: | arm_sme.copy_tile
+// CHECK-LIVE-RANGE-NEXT: E cf.br
+// CHECK-LIVE-RANGE-NEXT: ^bb2:
+// CHECK-LIVE-RANGE-NEXT: S arm_sme.get_tile
+// CHECK-LIVE-RANGE-NEXT: | arm_sme.copy_tile
+// CHECK-LIVE-RANGE-NEXT: E cf.br
+
+// CHECK-LABEL: @non_overlapping_branches
+func.func @non_overlapping_branches(%cond: i1) {
+ // CHECK: arm_sme.zero {tile_id = 0 : i32} : vector<[4]x[4]xf32>
+ // CHECK: arm_sme.get_tile {tile_id = 0 : i32} : vector<[4]x[4]xf32>
+ %tile = scf.if %cond -> vector<[4]x[4]xf32> {
+ // ^bb1:
+ %zero = arm_sme.zero : vector<[4]x[4]xf32>
+ scf.yield %zero : vector<[4]x[4]xf32>
+ } else {
+ // ^bb2:
+ %undef = arm_sme.get_tile : vector<[4]x[4]xf32>
+ scf.yield %undef : vector<[4]x[4]xf32>
+ }
+ "test.some_use"(%tile) : (vector<[4]x[4]xf32>) -> ()
+ return
+}
+
+// -----
+
+// CHECK-LIVE-RANGE: ========== Coalesced Live Ranges:
+// <deliberately omitted>
+
+// CHECK-LABEL: @constant_loop_init_with_multiple_users
+func.func @constant_loop_init_with_multiple_users(%a: vector<[4]xf32>, %b: vector<[4]xf32>) {
+ // CHECK: arm_sme.zero {tile_id = 0 : i32} : vector<[4]x[4]xf32>
+ // CHECK: arm_sme.zero {tile_id = 1 : i32} : vector<[4]x[4]xf32>
+ // CHECK: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 1 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
+ // CHECK: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 0 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
+ %c0 = arith.constant 0 : index
+ %c1 = arith.constant 1 : index
+ %c10 = arith.constant 10 : index
+ %init = arm_sme.zero : vector<[4]x[4]xf32>
+ %tile_a = scf.for %i = %c0 to %c10 step %c1 iter_args(%iter = %init) -> vector<[4]x[4]xf32> {
+ %new_tile = arm_sme.move_vector_to_tile_slice %a, %iter, %i : vector<[4]xf32> into vector<[4]x[4]xf32>
+ scf.yield %new_tile : vector<[4]x[4]xf32>
+ }
+ %tile_b = scf.for %i = %c0 to %c10 step %c1 iter_args(%iter = %init) -> vector<[4]x[4]xf32> {
+ %new_tile = arm_sme.move_vector_to_tile_slice %a, %iter, %i : vector<[4]xf32> into vector<[4]x[4]xf32>
+ scf.yield %new_tile : 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: @run_out_of_tiles_but_avoid_spill
+// CHECK-LIVE-RANGE: ^bb2:
+// CHECK-LIVE-RANGE-NEXT: |S arm_sme.copy_tile
+// CHECK-LIVE-RANGE-NEXT: ||S arm_sme.copy_tile
+// CHECK-LIVE-RANGE-NEXT: |||S arm_sme.copy_tile
+// CHECK-LIVE-RANGE-NEXT: ||||S arm_sme.copy_tile
+// CHECK-LIVE-RANGE-NEXT: EEEEE cf.br
+
+// Note in the live ranges (above) there is five tile values, but we only have four tiles.
+
+// CHECK-LABEL: @run_out_of_tiles_but_avoid_spill
+func.func @run_out_of_tiles_but_avoid_spill(%a: vector<[4]xf32>, %b: vector<[4]xf32>, %c: vector<[4]xf32>, %d: vector<[4]xf32>) {
+ %init = arm_sme.zero : vector<[4]x[4]xf32>
+ %c0 = arith.constant 0 : index
+ %c1 = arith.constant 1 : index
+ %c10 = arith.constant 10 : index
+ // Live = %init
+ scf.for %i = %c0 to %c10 step %c1 {
+ // CHECK: arm_sme.zero {tile_id = 1 : i32}
+ // CHECK: arm_sme.zero {tile_id = 2 : i32}
+ // CHECK: arm_sme.zero {tile_id = 3 : i32}
+ // CHECK: arm_sme.zero {tile_id = 0 : i32}
+ %tile_a, %tile_b, %tile_c, %tile_d = scf.for %j = %c0 to %c10 step %c1
+ iter_args(%iter_a = %init, %iter_b = %init, %iter_c = %init, %iter_d = %init)
+ -> (vector<[4]x[4]xf32>, vector<[4]x[4]xf32> , vector<[4]x[4]xf32> , vector<[4]x[4]xf32>) {
+ // ^bb2:
+ // CHECK: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 1 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
+ // CHECK: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 2 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
+ // CHECK: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 3 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
+ // CHECK: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 0 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
+ %new_a = arm_sme.move_vector_to_tile_slice %a, %iter_a, %i : vector<[4]xf32> into vector<[4]x[4]xf32>
+ %new_b = arm_sme.move_vector_to_tile_slice %b, %iter_b, %i : vector<[4]xf32> into vector<[4]x[4]xf32>
+ %new_c = arm_sme.move_vector_to_tile_slice %c, %iter_c, %i : vector<[4]xf32> into vector<[4]x[4]xf32>
+ %new_d = arm_sme.move_vector_to_tile_slice %d, %iter_d, %i : vector<[4]xf32> into vector<[4]x[4]xf32>
+ scf.yield %new_a, %new_b, %new_c, %new_d : vector<[4]x[4]xf32>, vector<[4]x[4]xf32>, vector<[4]x[4]xf32>, vector<[4]x[4]xf32>
+ }
+ // Live = %init, %tile_a, %tile_b, %tile_c, %tile_d (out of tiles!)
+ // This should be resolved by duplicating the arm_sme.zero (from folding
+ // arm_sme.copy_tile operations inserted by the tile allocator).
+ "test.some_use"(%tile_a) : (vector<[4]x[4]xf32>) -> ()
+ "test.some_use"(%tile_b) : (vector<[4]x[4]xf32>) -> ()
+ "test.some_use"(%tile_c) : (vector<[4]x[4]xf32>) -> ()
+ "test.some_use"(%tile_d) : (vector<[4]x[4]xf32>) -> ()
+ }
+ return
+}
+
+// -----
+
+// We should be able to avoid spills like this, but logic handling this case is
+// not implemented yet. Note tile ID >= 16 means a spill/in-memory tile.
+
+// CHECK-LIVE-RANGE: ========== Coalesced Live Ranges:
+// CHECK-LIVE-RANGE-NEXT: @avoidable_spill
+// CHECK-LIVE-RANGE: ^bb2:
+// CHECK-LIVE-RANGE-NEXT: || test.some_use
+// CHECK-LIVE-RANGE-NEXT: ||S arm_sme.move_vector_to_tile_slice
+// CHECK-LIVE-RANGE-NEXT: |||S arm_sme.move_vector_to_tile_slice
+// CHECK-LIVE-RANGE-NEXT: ||||S arm_sme.move_vector_to_tile_slice
+// CHECK-LIVE-RANGE-NEXT: |||||S arm_sme.move_vector_to_tile_slice
+// CHECK-LIVE-RANGE-NEXT: ||E||| test.some_use
+// CHECK-LIVE-RANGE-NEXT: || E|| test.some_use
+// CHECK-LIVE-RANGE-NEXT: || E| test.some_use
+// CHECK-LIVE-RANGE-NEXT: || E test.some_use
+// CHECK-LIVE-RANGE-NEXT: || arith.addi
+// CHECK-LIVE-RANGE-NEXT: EE cf.br
+
+// Note in the live ranges (above) there is two constant live-ins (first two ranges),
+// which gives six overlapping live ranges. The allocator currently will spill the
+// first constant (which results in a real spill at it's use), however, this could
+// be avoided by using the knowledge that at the first "test.some_use" there's
+// actually only two live ranges (so we can fix this be duplicating the constant).
+
+// CHECK-LABEL: @avoidable_spill
+func.func @avoidable_spill(%a: vector<[4]xf32>, %b: vector<[4]xf32>, %c: vector<[4]xf32>, %d: vector<[4]xf32>) {
+ // CHECK: arm_sme.zero {tile_id = 16 : i32} : vector<[4]x[4]xf32>
+ %zero = arm_sme.zero : vector<[4]x[4]xf32>
+ %tile = arm_sme.get_tile : vector<[4]x[4]xf32>
+ %c0 = arith.constant 0 : index
+ %c1 = arith.constant 1 : index
+ %c10 = arith.constant 10 : index
+ scf.for %i = %c0 to %c10 step %c1 {
+ // So spilled here (unnecessarily).
+ // The arm_sme.zero op could be moved into the loop to avoid this.
+ "test.some_use"(%zero) : (vector<[4]x[4]xf32>) -> ()
+ %tile_a = arm_sme.move_vector_to_tile_slice %a, %tile, %c0 : vector<[4]xf32> into vector<[4]x[4]xf32>
+ %tile_b = arm_sme.move_vector_to_tile_slice %b, %tile, %c0 : vector<[4]xf32> into vector<[4]x[4]xf32>
+ %tile_c = arm_sme.move_vector_to_tile_slice %c, %tile, %c0 : vector<[4]xf32> into vector<[4]x[4]xf32>
+ %tile_d = arm_sme.move_vector_to_tile_slice %d, %tile, %c0 : vector<[4]xf32> into vector<[4]x[4]xf32>
+ // %zero is still live here (due the the backedge)
+ "test.some_use"(%tile_a) : (vector<[4]x[4]xf32>) -> ()
+ "test.some_use"(%tile_b) : (vector<[4]x[4]xf32>) -> ()
+ "test.some_use"(%tile_c) : (vector<[4]x[4]xf32>) -> ()
+ "test.some_use"(%tile_d) : (vector<[4]x[4]xf32>) -> ()
+ }
+ return
+}
>From fde6523ab7e46b646b813d576e28168138a7dc3d Mon Sep 17 00:00:00 2001
From: Benjamin Maxwell <benjamin.maxwell at arm.com>
Date: Mon, 29 Apr 2024 16:15:52 +0000
Subject: [PATCH 2/4] Add `CHECK-BAD` tests for the current tile allocator
---
.../ArmSME/tile-allocation-liveness.mlir | 72 ++++++++++++++++---
1 file changed, 64 insertions(+), 8 deletions(-)
diff --git a/mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir b/mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir
index e7ca77f08ecc3f..5fc80e0ab3a89f 100644
--- a/mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir
+++ b/mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir
@@ -1,10 +1,12 @@
-// RUN: mlir-opt %s -allocate-arm-sme-tiles -split-input-file -verify-diagnostics | FileCheck %s
+// RUN: mlir-opt %s -allocate-arm-sme-tiles -split-input-file -verify-diagnostics | FileCheck %s --check-prefix=CHECK-BAD
-// This file tests some simple aspects of using liveness in the SME tile allocator.
-
-// Note: This is an XFAIL the new allocator is not yet upstream, and the current
-// allocator gives incorrect results for these tests.
-// XFAIL: *
+// 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
@@ -15,6 +17,14 @@
// 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) {
@@ -40,8 +50,10 @@ func.func @constant_with_multiple_users(%a: vector<[4]xf32>, %b: vector<[4]xf32>
// 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)
+
func.func @value_with_multiple_users(%tile: vector<[4]x[4]xf32>, %a: vector<[4]xf32>, %b: vector<[4]xf32>, %index: index) {
- // expected-error at below {{op failed to rectify tile operand with tile result (move required)}}
+ // A future allocator should error here (as `%`tile would need to be copied).
%tile_a = arm_sme.move_vector_to_tile_slice %a, %tile, %index : vector<[4]xf32> into vector<[4]x[4]xf32>
%tile_b = arm_sme.move_vector_to_tile_slice %b, %tile, %index : vector<[4]xf32> into vector<[4]x[4]xf32>
"test.some_use"(%tile_a) : (vector<[4]x[4]xf32>) -> ()
@@ -77,6 +89,19 @@ func.func @value_with_multiple_users(%tile: vector<[4]x[4]xf32>, %a: vector<[4]x
// CHECK-LIVE-RANGE-NEXT: E| test.some_use
// CHECK-LIVE-RANGE-NEXT: E test.some_use
+// CHECK-BAD-LABEL: @reuse_tiles_after_initial_use
+// CHECK-BAD: arm_sme.get_tile {tile_id = 0 : i32}
+// CHECK-BAD: arm_sme.get_tile {tile_id = 1 : i32}
+// CHECK-BAD: arm_sme.get_tile {tile_id = 2 : i32}
+// CHECK-BAD: arm_sme.get_tile {tile_id = 3 : i32}
+//
+// -> Spills after the fourth tile (unnecessary):
+//
+// CHECK-BAD: arm_sme.zero {tile_id = 16 : i32}
+// CHECK-BAD: arm_sme.zero {tile_id = 17 : i32}
+// CHECK-BAD: arm_sme.zero {tile_id = 18 : i32}
+// CHECK-BAD: arm_sme.zero {tile_id = 19 : i32}
+
// CHECK-LABEL: @reuse_tiles_after_initial_use
func.func @reuse_tiles_after_initial_use() {
// CHECK: arm_sme.get_tile {tile_id = 0 : i32}
@@ -98,9 +123,14 @@ func.func @reuse_tiles_after_initial_use() {
// CHECK: arm_sme.zero {tile_id = 1 : i32}
// CHECK: arm_sme.zero {tile_id = 2 : i32}
// CHECK: arm_sme.zero {tile_id = 3 : i32}
+ // Unnecessary spills:
+ // expected-warning @below {{failed to allocate SME virtual tile to operation, all tile operations will go through memory, expect degraded performance}}
%tile_1 = arm_sme.zero : vector<[4]x[4]xf32>
+ // expected-warning @below {{failed to allocate SME virtual tile to operation, all tile operations will go through memory, expect degraded performance}}
%tile_2 = arm_sme.zero : vector<[4]x[4]xf32>
+ // expected-warning @below {{failed to allocate SME virtual tile to operation, all tile operations will go through memory, expect degraded performance}}
%tile_3 = arm_sme.zero : vector<[4]x[4]xf32>
+ // expected-warning @below {{failed to allocate SME virtual tile to operation, all tile operations will go through memory, expect degraded performance}}
%tile_4 = arm_sme.zero : vector<[4]x[4]xf32>
"test.dummy"(): () -> ()
"test.dummy"(): () -> ()
@@ -125,6 +155,12 @@ func.func @reuse_tiles_after_initial_use() {
// CHECK-LIVE-RANGE-NEXT: | arm_sme.copy_tile
// CHECK-LIVE-RANGE-NEXT: E cf.br
+// Incorrect result! Both branches should yield the result via the same tile.
+//
+// CHECK-BAD-LABEL: @non_overlapping_branches
+// CHECK-BAD: arm_sme.zero {tile_id = 0 : i32} : vector<[4]x[4]xf32>
+// CHECK-BAD: arm_sme.get_tile {tile_id = 1 : i32} : vector<[4]x[4]xf32>
+
// CHECK-LABEL: @non_overlapping_branches
func.func @non_overlapping_branches(%cond: i1) {
// CHECK: arm_sme.zero {tile_id = 0 : i32} : vector<[4]x[4]xf32>
@@ -147,6 +183,13 @@ func.func @non_overlapping_branches(%cond: i1) {
// CHECK-LIVE-RANGE: ========== Coalesced Live Ranges:
// <deliberately omitted>
+// Incorrect result! Everything assigned to tile 0 (which means values that are still live are overwritten).
+//
+// CHECK-BAD-LABEL: @constant_loop_init_with_multiple_users
+// CHECK-BAD: arm_sme.zero {tile_id = 0 : i32} : vector<[4]x[4]xf32>
+// CHECK-BAD: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 0 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
+// CHECK-BAD: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 0 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
+
// CHECK-LABEL: @constant_loop_init_with_multiple_users
func.func @constant_loop_init_with_multiple_users(%a: vector<[4]xf32>, %b: vector<[4]xf32>) {
// CHECK: arm_sme.zero {tile_id = 0 : i32} : vector<[4]x[4]xf32>
@@ -183,6 +226,12 @@ func.func @constant_loop_init_with_multiple_users(%a: vector<[4]xf32>, %b: vecto
// Note in the live ranges (above) there is five tile values, but we only have four tiles.
+// Incorrect result! Everything assigned to tile 0 (which means values that are still live are overwritten).
+//
+// CHECK-BAD-LABEL: @run_out_of_tiles_but_avoid_spill
+// CHECK-BAD: arm_sme.zero {tile_id = 0 : i32}
+// CHECK-BAD-COUNT-4: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 0 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
+
// CHECK-LABEL: @run_out_of_tiles_but_avoid_spill
func.func @run_out_of_tiles_but_avoid_spill(%a: vector<[4]xf32>, %b: vector<[4]xf32>, %c: vector<[4]xf32>, %d: vector<[4]xf32>) {
%init = arm_sme.zero : vector<[4]x[4]xf32>
@@ -239,13 +288,20 @@ func.func @run_out_of_tiles_but_avoid_spill(%a: vector<[4]xf32>, %b: vector<[4]x
// CHECK-LIVE-RANGE-NEXT: || E test.some_use
// CHECK-LIVE-RANGE-NEXT: || arith.addi
// CHECK-LIVE-RANGE-NEXT: EE cf.br
-
+//
// Note in the live ranges (above) there is two constant live-ins (first two ranges),
// which gives six overlapping live ranges. The allocator currently will spill the
// first constant (which results in a real spill at it's use), however, this could
// be avoided by using the knowledge that at the first "test.some_use" there's
// actually only two live ranges (so we can fix this be duplicating the constant).
+// Incorrect result! Everything other than zero assigned to tile 1 (which means values that are still live are overwritten).
+//
+// CHECK-BAD-LABEL: @avoidable_spill
+// CHECK-BAD: arm_sme.zero {tile_id = 0 : i32}
+// CHECK-BAD: arm_sme.get_tile {tile_id = 1 : i32}
+// CHECK-BAD-COUNT-4: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 1 : i32}
+
// CHECK-LABEL: @avoidable_spill
func.func @avoidable_spill(%a: vector<[4]xf32>, %b: vector<[4]xf32>, %c: vector<[4]xf32>, %d: vector<[4]xf32>) {
// CHECK: arm_sme.zero {tile_id = 16 : i32} : vector<[4]x[4]xf32>
>From 277f684015ddbbd83ce3eb366607b159add0c5f6 Mon Sep 17 00:00:00 2001
From: Benjamin Maxwell <benjamin.maxwell at arm.com>
Date: Tue, 30 Apr 2024 15:01:08 +0000
Subject: [PATCH 3/4] Remove new allocator checks
---
.../ArmSME/tile-allocation-liveness.mlir | 182 ++----------------
1 file changed, 17 insertions(+), 165 deletions(-)
diff --git a/mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir b/mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir
index 5fc80e0ab3a89f..b5dac8733e61c7 100644
--- a/mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir
+++ b/mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir
@@ -1,37 +1,18 @@
// 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
+// These tests were designed with a new liveness-based tile allocator in mind
+// (where the names of test cases make more sense), with the current tile
+// allocator these tests all give incorrect results (which is documented by
+// `CHECK-BAD`).
// 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-LABEL: @constant_with_multiple_users
// 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>
+// CHECK-BAD: %[[INSERT_TILE_1:.*]] = arm_sme.move_vector_to_tile_slice %{{.*}} {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 %{{.*}} {tile_id = 0 : i32} : vector<[4]xf32> into vector<[4]x[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>
@@ -42,18 +23,9 @@ func.func @constant_with_multiple_users(%a: vector<[4]xf32>, %b: vector<[4]xf32>
// -----
-// 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)
-
func.func @value_with_multiple_users(%tile: vector<[4]x[4]xf32>, %a: vector<[4]xf32>, %b: vector<[4]xf32>, %index: index) {
- // A future allocator should error here (as `%`tile would need to be copied).
+ // A future allocator should error here (as `%tile` would need to be copied).
%tile_a = arm_sme.move_vector_to_tile_slice %a, %tile, %index : vector<[4]xf32> into vector<[4]x[4]xf32>
%tile_b = arm_sme.move_vector_to_tile_slice %b, %tile, %index : vector<[4]xf32> into vector<[4]x[4]xf32>
"test.some_use"(%tile_a) : (vector<[4]x[4]xf32>) -> ()
@@ -63,51 +35,12 @@ func.func @value_with_multiple_users(%tile: vector<[4]x[4]xf32>, %a: vector<[4]x
// -----
-// CHECK-LIVE-RANGE: ========== Coalesced Live Ranges:
-// CHECK-LIVE-RANGE-NEXT: @reuse_tiles_after_initial_use
-// CHECK-LIVE-RANGE: ^bb0:
-// CHECK-LIVE-RANGE-NEXT: S arm_sme.get_tile
-// CHECK-LIVE-RANGE-NEXT: |S arm_sme.get_tile
-// CHECK-LIVE-RANGE-NEXT: ||S arm_sme.get_tile
-// CHECK-LIVE-RANGE-NEXT: |||S arm_sme.get_tile
-// CHECK-LIVE-RANGE-NEXT: |||| test.dummy
-// CHECK-LIVE-RANGE-NEXT: |||| test.dummy
-// CHECK-LIVE-RANGE-NEXT: |||| test.dummy
-// CHECK-LIVE-RANGE-NEXT: E||| test.some_use
-// CHECK-LIVE-RANGE-NEXT: E|| test.some_use
-// CHECK-LIVE-RANGE-NEXT: E| test.some_use
-// CHECK-LIVE-RANGE-NEXT: E test.some_use
-// CHECK-LIVE-RANGE-NEXT: S arm_sme.zero
-// CHECK-LIVE-RANGE-NEXT: |S arm_sme.zero
-// CHECK-LIVE-RANGE-NEXT: ||S arm_sme.zero
-// CHECK-LIVE-RANGE-NEXT: |||S arm_sme.zero
-// CHECK-LIVE-RANGE-NEXT: |||| test.dummy
-// CHECK-LIVE-RANGE-NEXT: |||| test.dummy
-// CHECK-LIVE-RANGE-NEXT: |||| test.dummy
-// CHECK-LIVE-RANGE-NEXT: E||| test.some_use
-// CHECK-LIVE-RANGE-NEXT: E|| test.some_use
-// CHECK-LIVE-RANGE-NEXT: E| test.some_use
-// CHECK-LIVE-RANGE-NEXT: E test.some_use
-
// CHECK-BAD-LABEL: @reuse_tiles_after_initial_use
-// CHECK-BAD: arm_sme.get_tile {tile_id = 0 : i32}
-// CHECK-BAD: arm_sme.get_tile {tile_id = 1 : i32}
-// CHECK-BAD: arm_sme.get_tile {tile_id = 2 : i32}
-// CHECK-BAD: arm_sme.get_tile {tile_id = 3 : i32}
-//
-// -> Spills after the fourth tile (unnecessary):
-//
-// CHECK-BAD: arm_sme.zero {tile_id = 16 : i32}
-// CHECK-BAD: arm_sme.zero {tile_id = 17 : i32}
-// CHECK-BAD: arm_sme.zero {tile_id = 18 : i32}
-// CHECK-BAD: arm_sme.zero {tile_id = 19 : i32}
-
-// CHECK-LABEL: @reuse_tiles_after_initial_use
func.func @reuse_tiles_after_initial_use() {
- // CHECK: arm_sme.get_tile {tile_id = 0 : i32}
- // CHECK: arm_sme.get_tile {tile_id = 1 : i32}
- // CHECK: arm_sme.get_tile {tile_id = 2 : i32}
- // CHECK: arm_sme.get_tile {tile_id = 3 : i32}
+ // CHECK-BAD: arm_sme.get_tile {tile_id = 0 : i32}
+ // CHECK-BAD: arm_sme.get_tile {tile_id = 1 : i32}
+ // CHECK-BAD: arm_sme.get_tile {tile_id = 2 : i32}
+ // CHECK-BAD: arm_sme.get_tile {tile_id = 3 : i32}
%tile_a = arm_sme.get_tile : vector<[4]x[4]xf32>
%tile_b = arm_sme.get_tile : vector<[4]x[4]xf32>
%tile_c = arm_sme.get_tile : vector<[4]x[4]xf32>
@@ -119,10 +52,11 @@ func.func @reuse_tiles_after_initial_use() {
"test.some_use"(%tile_b) : (vector<[4]x[4]xf32>) -> ()
"test.some_use"(%tile_c) : (vector<[4]x[4]xf32>) -> ()
"test.some_use"(%tile_d) : (vector<[4]x[4]xf32>) -> ()
- // CHECK: arm_sme.zero {tile_id = 0 : i32}
- // CHECK: arm_sme.zero {tile_id = 1 : i32}
- // CHECK: arm_sme.zero {tile_id = 2 : i32}
- // CHECK: arm_sme.zero {tile_id = 3 : i32}
+ // -> Spills after the fourth tile (unnecessary):
+ // CHECK-BAD: arm_sme.zero {tile_id = 16 : i32}
+ // CHECK-BAD: arm_sme.zero {tile_id = 17 : i32}
+ // CHECK-BAD: arm_sme.zero {tile_id = 18 : i32}
+ // CHECK-BAD: arm_sme.zero {tile_id = 19 : i32}
// Unnecessary spills:
// expected-warning @below {{failed to allocate SME virtual tile to operation, all tile operations will go through memory, expect degraded performance}}
%tile_1 = arm_sme.zero : vector<[4]x[4]xf32>
@@ -144,33 +78,16 @@ func.func @reuse_tiles_after_initial_use() {
// -----
-// CHECK-LIVE-RANGE: ========== Coalesced Live Ranges:
-// CHECK-LIVE-RANGE-NEXT: @non_overlapping_branches
-// CHECK-LIVE-RANGE: ^bb1:
-// CHECK-LIVE-RANGE-NEXT: S arm_sme.zero
-// CHECK-LIVE-RANGE-NEXT: | arm_sme.copy_tile
-// CHECK-LIVE-RANGE-NEXT: E cf.br
-// CHECK-LIVE-RANGE-NEXT: ^bb2:
-// CHECK-LIVE-RANGE-NEXT: S arm_sme.get_tile
-// CHECK-LIVE-RANGE-NEXT: | arm_sme.copy_tile
-// CHECK-LIVE-RANGE-NEXT: E cf.br
-
// Incorrect result! Both branches should yield the result via the same tile.
//
// CHECK-BAD-LABEL: @non_overlapping_branches
// CHECK-BAD: arm_sme.zero {tile_id = 0 : i32} : vector<[4]x[4]xf32>
// CHECK-BAD: arm_sme.get_tile {tile_id = 1 : i32} : vector<[4]x[4]xf32>
-
-// CHECK-LABEL: @non_overlapping_branches
func.func @non_overlapping_branches(%cond: i1) {
- // CHECK: arm_sme.zero {tile_id = 0 : i32} : vector<[4]x[4]xf32>
- // CHECK: arm_sme.get_tile {tile_id = 0 : i32} : vector<[4]x[4]xf32>
%tile = scf.if %cond -> vector<[4]x[4]xf32> {
- // ^bb1:
%zero = arm_sme.zero : vector<[4]x[4]xf32>
scf.yield %zero : vector<[4]x[4]xf32>
} else {
- // ^bb2:
%undef = arm_sme.get_tile : vector<[4]x[4]xf32>
scf.yield %undef : vector<[4]x[4]xf32>
}
@@ -180,22 +97,13 @@ func.func @non_overlapping_branches(%cond: i1) {
// -----
-// CHECK-LIVE-RANGE: ========== Coalesced Live Ranges:
-// <deliberately omitted>
-
// Incorrect result! Everything assigned to tile 0 (which means values that are still live are overwritten).
//
// CHECK-BAD-LABEL: @constant_loop_init_with_multiple_users
// CHECK-BAD: arm_sme.zero {tile_id = 0 : i32} : vector<[4]x[4]xf32>
// CHECK-BAD: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 0 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
// CHECK-BAD: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 0 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
-
-// CHECK-LABEL: @constant_loop_init_with_multiple_users
func.func @constant_loop_init_with_multiple_users(%a: vector<[4]xf32>, %b: vector<[4]xf32>) {
- // CHECK: arm_sme.zero {tile_id = 0 : i32} : vector<[4]x[4]xf32>
- // CHECK: arm_sme.zero {tile_id = 1 : i32} : vector<[4]x[4]xf32>
- // CHECK: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 1 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
- // CHECK: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 0 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
%c0 = arith.constant 0 : index
%c1 = arith.constant 1 : index
%c10 = arith.constant 10 : index
@@ -215,52 +123,26 @@ func.func @constant_loop_init_with_multiple_users(%a: vector<[4]xf32>, %b: vecto
// -----
-// CHECK-LIVE-RANGE: ========== Coalesced Live Ranges:
-// CHECK-LIVE-RANGE-NEXT: @run_out_of_tiles_but_avoid_spill
-// CHECK-LIVE-RANGE: ^bb2:
-// CHECK-LIVE-RANGE-NEXT: |S arm_sme.copy_tile
-// CHECK-LIVE-RANGE-NEXT: ||S arm_sme.copy_tile
-// CHECK-LIVE-RANGE-NEXT: |||S arm_sme.copy_tile
-// CHECK-LIVE-RANGE-NEXT: ||||S arm_sme.copy_tile
-// CHECK-LIVE-RANGE-NEXT: EEEEE cf.br
-
-// Note in the live ranges (above) there is five tile values, but we only have four tiles.
-
// Incorrect result! Everything assigned to tile 0 (which means values that are still live are overwritten).
//
// CHECK-BAD-LABEL: @run_out_of_tiles_but_avoid_spill
// CHECK-BAD: arm_sme.zero {tile_id = 0 : i32}
// CHECK-BAD-COUNT-4: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 0 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
-
-// CHECK-LABEL: @run_out_of_tiles_but_avoid_spill
func.func @run_out_of_tiles_but_avoid_spill(%a: vector<[4]xf32>, %b: vector<[4]xf32>, %c: vector<[4]xf32>, %d: vector<[4]xf32>) {
%init = arm_sme.zero : vector<[4]x[4]xf32>
%c0 = arith.constant 0 : index
%c1 = arith.constant 1 : index
%c10 = arith.constant 10 : index
- // Live = %init
scf.for %i = %c0 to %c10 step %c1 {
- // CHECK: arm_sme.zero {tile_id = 1 : i32}
- // CHECK: arm_sme.zero {tile_id = 2 : i32}
- // CHECK: arm_sme.zero {tile_id = 3 : i32}
- // CHECK: arm_sme.zero {tile_id = 0 : i32}
%tile_a, %tile_b, %tile_c, %tile_d = scf.for %j = %c0 to %c10 step %c1
iter_args(%iter_a = %init, %iter_b = %init, %iter_c = %init, %iter_d = %init)
-> (vector<[4]x[4]xf32>, vector<[4]x[4]xf32> , vector<[4]x[4]xf32> , vector<[4]x[4]xf32>) {
- // ^bb2:
- // CHECK: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 1 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
- // CHECK: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 2 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
- // CHECK: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 3 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
- // CHECK: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 0 : i32} : vector<[4]xf32> into vector<[4]x[4]xf32>
%new_a = arm_sme.move_vector_to_tile_slice %a, %iter_a, %i : vector<[4]xf32> into vector<[4]x[4]xf32>
%new_b = arm_sme.move_vector_to_tile_slice %b, %iter_b, %i : vector<[4]xf32> into vector<[4]x[4]xf32>
%new_c = arm_sme.move_vector_to_tile_slice %c, %iter_c, %i : vector<[4]xf32> into vector<[4]x[4]xf32>
%new_d = arm_sme.move_vector_to_tile_slice %d, %iter_d, %i : vector<[4]xf32> into vector<[4]x[4]xf32>
scf.yield %new_a, %new_b, %new_c, %new_d : vector<[4]x[4]xf32>, vector<[4]x[4]xf32>, vector<[4]x[4]xf32>, vector<[4]x[4]xf32>
}
- // Live = %init, %tile_a, %tile_b, %tile_c, %tile_d (out of tiles!)
- // This should be resolved by duplicating the arm_sme.zero (from folding
- // arm_sme.copy_tile operations inserted by the tile allocator).
"test.some_use"(%tile_a) : (vector<[4]x[4]xf32>) -> ()
"test.some_use"(%tile_b) : (vector<[4]x[4]xf32>) -> ()
"test.some_use"(%tile_c) : (vector<[4]x[4]xf32>) -> ()
@@ -271,54 +153,24 @@ func.func @run_out_of_tiles_but_avoid_spill(%a: vector<[4]xf32>, %b: vector<[4]x
// -----
-// We should be able to avoid spills like this, but logic handling this case is
-// not implemented yet. Note tile ID >= 16 means a spill/in-memory tile.
-
-// CHECK-LIVE-RANGE: ========== Coalesced Live Ranges:
-// CHECK-LIVE-RANGE-NEXT: @avoidable_spill
-// CHECK-LIVE-RANGE: ^bb2:
-// CHECK-LIVE-RANGE-NEXT: || test.some_use
-// CHECK-LIVE-RANGE-NEXT: ||S arm_sme.move_vector_to_tile_slice
-// CHECK-LIVE-RANGE-NEXT: |||S arm_sme.move_vector_to_tile_slice
-// CHECK-LIVE-RANGE-NEXT: ||||S arm_sme.move_vector_to_tile_slice
-// CHECK-LIVE-RANGE-NEXT: |||||S arm_sme.move_vector_to_tile_slice
-// CHECK-LIVE-RANGE-NEXT: ||E||| test.some_use
-// CHECK-LIVE-RANGE-NEXT: || E|| test.some_use
-// CHECK-LIVE-RANGE-NEXT: || E| test.some_use
-// CHECK-LIVE-RANGE-NEXT: || E test.some_use
-// CHECK-LIVE-RANGE-NEXT: || arith.addi
-// CHECK-LIVE-RANGE-NEXT: EE cf.br
-//
-// Note in the live ranges (above) there is two constant live-ins (first two ranges),
-// which gives six overlapping live ranges. The allocator currently will spill the
-// first constant (which results in a real spill at it's use), however, this could
-// be avoided by using the knowledge that at the first "test.some_use" there's
-// actually only two live ranges (so we can fix this be duplicating the constant).
-
// Incorrect result! Everything other than zero assigned to tile 1 (which means values that are still live are overwritten).
//
// CHECK-BAD-LABEL: @avoidable_spill
// CHECK-BAD: arm_sme.zero {tile_id = 0 : i32}
// CHECK-BAD: arm_sme.get_tile {tile_id = 1 : i32}
// CHECK-BAD-COUNT-4: arm_sme.move_vector_to_tile_slice {{.*}} {tile_id = 1 : i32}
-
-// CHECK-LABEL: @avoidable_spill
func.func @avoidable_spill(%a: vector<[4]xf32>, %b: vector<[4]xf32>, %c: vector<[4]xf32>, %d: vector<[4]xf32>) {
- // CHECK: arm_sme.zero {tile_id = 16 : i32} : vector<[4]x[4]xf32>
%zero = arm_sme.zero : vector<[4]x[4]xf32>
%tile = arm_sme.get_tile : vector<[4]x[4]xf32>
%c0 = arith.constant 0 : index
%c1 = arith.constant 1 : index
%c10 = arith.constant 10 : index
scf.for %i = %c0 to %c10 step %c1 {
- // So spilled here (unnecessarily).
- // The arm_sme.zero op could be moved into the loop to avoid this.
"test.some_use"(%zero) : (vector<[4]x[4]xf32>) -> ()
%tile_a = arm_sme.move_vector_to_tile_slice %a, %tile, %c0 : vector<[4]xf32> into vector<[4]x[4]xf32>
%tile_b = arm_sme.move_vector_to_tile_slice %b, %tile, %c0 : vector<[4]xf32> into vector<[4]x[4]xf32>
%tile_c = arm_sme.move_vector_to_tile_slice %c, %tile, %c0 : vector<[4]xf32> into vector<[4]x[4]xf32>
%tile_d = arm_sme.move_vector_to_tile_slice %d, %tile, %c0 : vector<[4]xf32> into vector<[4]x[4]xf32>
- // %zero is still live here (due the the backedge)
"test.some_use"(%tile_a) : (vector<[4]x[4]xf32>) -> ()
"test.some_use"(%tile_b) : (vector<[4]x[4]xf32>) -> ()
"test.some_use"(%tile_c) : (vector<[4]x[4]xf32>) -> ()
>From 6fd383dcb45736aebabc1138a85bec9a3ef61905 Mon Sep 17 00:00:00 2001
From: Benjamin Maxwell <benjamin.maxwell at arm.com>
Date: Wed, 1 May 2024 12:54:45 +0000
Subject: [PATCH 4/4] Add CHECK-NOT
---
mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir b/mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir
index b5dac8733e61c7..2dedcb2fbc24e4 100644
--- a/mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir
+++ b/mlir/test/Dialect/ArmSME/tile-allocation-liveness.mlir
@@ -23,7 +23,10 @@ func.func @constant_with_multiple_users(%a: vector<[4]xf32>, %b: vector<[4]xf32>
// -----
-// (No CHECK-BAD -- the current tile allocator ignores this case)
+// (No tile IDs -- the current tile allocator ignores this case)
+
+// CHECK-BAD-LABEL: @value_with_multiple_users
+// CHECK-BAD-NOT: tile_id
func.func @value_with_multiple_users(%tile: vector<[4]x[4]xf32>, %a: vector<[4]xf32>, %b: vector<[4]xf32>, %index: index) {
// A future allocator should error here (as `%tile` would need to be copied).
%tile_a = arm_sme.move_vector_to_tile_slice %a, %tile, %index : vector<[4]xf32> into vector<[4]x[4]xf32>
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