feat: constant fold tosa.tile when input is splat.

Author: ttjost

mlir/lib/Dialect/Tosa/Transforms/TosaFolders.cpp

@@ -1736,6 +1736,14 @@ DenseElementsAttr tile(DenseElementsAttr inputValues, ShapedType outputType) {
   auto inputType = inputValues.getType();
   auto baseType = inputType.getElementType();
 
+  if (inputValues.isSplat()) {
+    if (isa<IntegerType>(baseType))
+      return DenseElementsAttr::get(outputType,
+                                    inputValues.getSplatValue<APInt>());
+    return DenseElementsAttr::get(outputType,
+                                  inputValues.getSplatValue<APFloat>());
+  }
+
   // Handle possible integer types
   if (auto intType = dyn_cast<IntegerType>(baseType)) {
     switch (intType.getWidth()) {

mlir/test/Dialect/Tosa/constant-tile.mlir

@@ -106,4 +106,40 @@ func.func @tile_f16_many_dimensions() -> (tensor<6x2x2xf16>) {
   %1 = tosa.tile %0 {multiples = array<i64: 3, 2, 1>} : (tensor<3x1x1xf16>) -> tensor<6x2x2xf16>
   // NO-FOLDING-CHECK: tosa.tile
   return %1 : tensor<6x2x2xf16>
+}
+
+// CHECK-LABEL: @tile_i1_splat
+func.func @tile_i1_splat() -> (tensor<1x2x2x2xi1>) {
+  // CHECK: "tosa.const"() <{value = dense<false> : tensor<1x2x2x2xi1>}>
+  %0 = "tosa.const"() <{value = dense<false> : tensor<1x1x1x1xi1>}> : () -> tensor<1x1x1x1xi1>
+  %1 = tosa.tile %0 {multiples = array<i64: 1, 2, 2, 2>} : (tensor<1x1x1x1xi1>) -> tensor<1x2x2x2xi1>
+  // NO-FOLDING-CHECK: tosa.tile
+  return %1 : tensor<1x2x2x2xi1>
+}
+
+// CHECK-LABEL: @tile_i32_splat
+func.func @tile_i32_splat() -> (tensor<1x2x2x2xi32>) {
+  // CHECK: "tosa.const"() <{value = dense<2> : tensor<1x2x2x2xi32>}>
+  %0 = "tosa.const"() <{value = dense<2> : tensor<1x1x1x1xi32>}> : () -> tensor<1x1x1x1xi32>
+  %1 = tosa.tile %0 {multiples = array<i64: 1, 2, 2, 2>} : (tensor<1x1x1x1xi32>) -> tensor<1x2x2x2xi32>
+  // NO-FOLDING-CHECK: tosa.tile
+  return %1 : tensor<1x2x2x2xi32>
+}
+
+// CHECK-LABEL: @tile_f16_splat
+func.func @tile_f16_splat() -> (tensor<1x2x2x2xf16>) {
+  // CHECK: "tosa.const"() <{value = dense<1.000000e+00> : tensor<1x2x2x2xf16>}>
+  %0 = "tosa.const"() <{value = dense<1.000000e+00> : tensor<1x1x1x1xf16>}> : () -> tensor<1x1x1x1xf16>
+  %1 = tosa.tile %0 {multiples = array<i64: 1, 2, 2, 2>} : (tensor<1x1x1x1xf16>) -> tensor<1x2x2x2xf16>
+  // NO-FOLDING-CHECK: tosa.tile
+  return %1 : tensor<1x2x2x2xf16>
+}
+
+// CHECK-LABEL: @tile_bf16_splat
+func.func @tile_bf16_splat() -> (tensor<1x2x2x2xbf16>) {
+  // CHECK: "tosa.const"() <{value = dense<1.000000e+00> : tensor<1x2x2x2xbf16>}>
+  %0 = "tosa.const"() <{value = dense<1.000000e+00> : tensor<1x1x1x1xbf16>}> : () -> tensor<1x1x1x1xbf16>
+  %1 = tosa.tile %0 {multiples = array<i64: 1, 2, 2, 2>} : (tensor<1x1x1x1xbf16>) -> tensor<1x2x2x2xbf16>
+  // NO-FOLDING-CHECK: tosa.tile
+  return %1 : tensor<1x2x2x2xbf16>
 }