[StableHLO] Add missing pointwise op tests (#13066)

Add tests for `stablehlo.not` and `stablehlo.complex`. These were not
present in the equivalent mlir-hlo tests.

Issue: #12678

compiler/src/iree/compiler/InputConversion/StableHLO/test/stablehlo_to_linalg_pointwise.mlir

@@ -1445,4 +1445,45 @@ func.func @reduce_precision(%arg0: tensor<1x2x3x4xf32>)
                             -> tensor<1x2x3x4xf32> {
   %0 = "stablehlo.reduce_precision"(%arg0) {exponent_bits=3:i32, mantissa_bits=3:i32} : (tensor<1x2x3x4xf32>) -> tensor<1x2x3x4xf32>
   return %0 : tensor<1x2x3x4xf32>
-}
+}
+
+// -----
+
+// CHECK-LABEL: func @integer_not
+// CHECK-SAME:    (%[[ARG:.+]]: tensor<2x2xi32>)
+// CHECK-PRIMITIVE-LABEL: func @integer_not
+// CHECK-PRIMITIVE-SAME:    (%[[ARG:.+]]: tensor<2x2xi32>)
+func.func @integer_not(%arg: tensor<2x2xi32>) -> tensor<2x2xi32> {
+  // CHECK: %[[CST_N1:.+]] = arith.constant -1 : i32
+  // CHECK: linalg.generic
+  // CHECK:   (%[[IN:.+]]: i32, %{{.+}}: i32)
+  // CHECK:   %[[V_NOT:.+]] = arith.xori %[[IN]], %[[CST_N1]] : i32
+  // CHECK:   linalg.yield %[[V_NOT]] : i32
+  // CHECK-PRIMITIVE: %[[CST_N1:.+]] = arith.constant -1 : i32
+  // CHECK-PRIMITIVE: linalg.map
+  // CHECK-PRIMITIVE:   (%[[IN:.+]]: i32)
+  // CHECK-PRIMITIVE:   %[[V_NOT:.+]] = arith.xori %[[IN]], %[[CST_N1]] : i32
+  // CHECK-PRIMITIVE:   linalg.yield %[[V_NOT]] : i32
+  %0 = "stablehlo.not"(%arg) : (tensor<2x2xi32>) -> tensor<2x2xi32>
+  func.return %0 : tensor<2x2xi32>
+}
+
+// -----
+
+// CHECK-LABEL: func @float_complex
+// CHECK-SAME:    (%[[LHS:.+]]: tensor<2x2xf32>, %[[RHS:.+]]: tensor<2x2xf32>)
+// CHECK-PRIMITIVE-LABEL: func @float_complex
+// CHECK-PRIMITIVE-SAME:    (%[[LHS:.+]]: tensor<2x2xf32>, %[[RHS:.+]]: tensor<2x2xf32>)
+func.func @float_complex(%lhs: tensor<2x2xf32>, %rhs: tensor<2x2xf32>) -> tensor<2x2xcomplex<f32>> {
+  // CHECK:      %[[INIT]] = tensor.empty() : tensor<2x2xcomplex<f32>>
+  // CHECK:      linalg.generic
+  // CHECK-SAME: ins(%[[LHS]], %[[RHS]]
+  // CHECK:      (%[[IN0:.+]]: f32, %[[IN1:.+]]: f32, %{{.+}}: complex<f32>
+  // CHECK:      %[[RES:.+]] = complex.create %[[IN0]], %[[IN1]] : complex<f32>
+  // CHECK:      linalg.yield %[[RES]] : complex<f32>
+  // CHECK-PRIMITIVE:      %[[INIT]] = tensor.empty() : tensor<2x2xcomplex<f32>>
+  // CHECK-PRIMITIVE:      linalg.map { complex.create } ins(%[[LHS]], %[[RHS]] : tensor<2x2xf32>, tensor<2x2xf32>)
+  // CHECK-PRIMITIVE-SAME: outs(%[[INIT]] : tensor<2x2xcomplex<f32>>)
+  %0 = "stablehlo.complex"(%lhs, %rhs) : (tensor<2x2xf32>, tensor<2x2xf32>) -> tensor<2x2xcomplex<f32>>
+  func.return %0 : tensor<2x2xcomplex<f32>>
+}