[Mlir-commits] [mlir] [mlir][scf] Considering affine.apply when fusing scf::ParallelOp (PR #80145)

[Ivan Butygin]

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@@ -480,3 +480,49 @@ func.func @do_not_fuse_multiple_stores_on_diff_indices(
 // CHECK:        scf.reduce
 // CHECK:      }
 // CHECK:      memref.dealloc [[SUM]]
+
+// -----
+
+func.func @fuse_same_indices_by_affine_apply(
+  %A: memref<2x2xf32>, %B: memref<2x2xf32>) {
+  %c0 = arith.constant 0 : index
+  %c1 = arith.constant 1 : index
+  %c2 = arith.constant 2 : index
+  %sum = memref.alloc()  : memref<2x3xf32>
+  scf.parallel (%i, %j) = (%c0, %c0) to (%c2, %c2) step (%c1, %c1) {
+    %B_elem = memref.load %B[%i, %j] : memref<2x2xf32>
+    %1 = affine.apply affine_map<(d0, d1) -> (d0 + d1)>(%i, %j)
+    memref.store %B_elem, %sum[%i, %1] : memref<2x3xf32>
+    scf.reduce
+  }
+  scf.parallel (%i, %j) = (%c0, %c0) to (%c2, %c2) step (%c1, %c1) {
+    %1 = affine.apply affine_map<(d0, d1) -> (d0 + d1)>(%i, %j)
+    %sum_elem = memref.load %sum[%i, %1] : memref<2x3xf32>
+    %A_elem = memref.load %A[%i, %j] : memref<2x2xf32>
+    %product = arith.mulf %sum_elem, %A_elem : f32
+    memref.store %product, %B[%i, %j] : memref<2x2xf32>
+    scf.reduce
+  }
+  memref.dealloc %sum : memref<2x3xf32>
+  return
+}
+// CHECK:      #[[$MAP:.+]] = affine_map<(d0, d1) -> (d0 + d1)>
+// CHECK-LABEL: fuse_same_indices_by_affine_apply
+// CHECK-SAME:  (%[[ARG0:.+]]: memref<2x2xf32>, %[[ARG1:.+]]: memref<2x2xf32>) {
+// CHECK-DAG:   %[[C0:.+]] = arith.constant 0 : index
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Hardcode84 wrote:

nit: SSA names are not guaranteed to be numbers (op can overload asmInterface to generate arbitrary names), so it's better to use `.*`

https://github.com/llvm/llvm-project/pull/80145