feat(aten::prelu): Basic prelu support

Signed-off-by: Naren Dasan <naren@narendasan.com>
Signed-off-by: Naren Dasan <narens@nvidia.com>

Author: narendasan

core/conversion/converters/impl/activation.cpp

@@ -79,6 +79,27 @@ auto acthardtanh TRTORCH_UNUSED = RegisterNodeConversionPatterns()
       new_layer->setName(util::node_info(n).c_str());
       auto out_tensor = ctx->AssociateValueAndTensor(n->outputs()[0], new_layer->getOutput(0));
 
+      LOG_DEBUG("Output shape: " << out_tensor->getDimensions());
+      return true;
+    }
+  }).pattern({
+    "aten::prelu(Tensor self, Tensor weight) -> (Tensor)",
+    [](ConversionCtx* ctx, const torch::jit::Node* n, args& args) -> bool {
+      auto in = args[0].ITensor();
+      auto slopes = args[1].unwrapToTensor();
+
+      //if (slopes.numel() != 1) {
+      //  auto in_dims = util::toVec(in.getDimensions());
+      // auto per_channel_shape = std::vector<int64_t>(in_dims.begin() + 2, in_dims.end());
+      //  for ()
+      //}
+
+      auto slope_tensor = tensor_to_const(ctx, slopes);
+
+      auto new_layer = ctx->net->addParametricReLU(*in, *slope_tensor);
+      new_layer->setName(util::node_info(n).c_str());
+      auto out_tensor = ctx->AssociateValueAndTensor(n->outputs()[0], new_layer->getOutput(0));
+
       LOG_DEBUG("Output shape: " << out_tensor->getDimensions());
       return true;
     }

tests/core/converters/test_activation.cpp

@@ -109,3 +109,50 @@ TEST(Converters, ATenHardTanhCustomRangeConvertsCorrectly) {
     ASSERT_TRUE(trtorch::tests::util::almostEqual(jit_results[0], trt_results[0], 2e-6));
 }
 
+TEST(Converters, ATenPReLUConvertsCorrectly) {
+    const auto graph = R"IR(
+      graph(%0 : Tensor,
+            %1 : Float(1)):
+        %3 : Tensor = aten::prelu(%0, %1)
+        return (%3))IR";
+
+    auto g = std::make_shared<torch::jit::Graph>();
+    torch::jit::parseIR(graph, &*g);
+
+    auto in = at::randint(-5, 5, {5}, {at::kCUDA});
+    auto slope = at::randint(-5, 5, {1}, {at::kCUDA});
+
+    auto params = trtorch::core::conversion::get_named_params(g->inputs(), {slope});
+    auto jit_results = trtorch::tests::util::RunGraph(g, params, {in});
+
+    in = at::clone(in);
+    params = trtorch::core::conversion::get_named_params(g->inputs(), {slope});
+    auto trt_results = trtorch::tests::util::RunGraphEngine(g, params, {in});
+
+    ASSERT_TRUE(trtorch::tests::util::almostEqual(jit_results[0], trt_results[0], 2e-6));
+}
+
+TEST(Converters, ATenPReLUMultiChannelConvertsCorrectly) {
+    const auto graph = R"IR(
+      graph(%0 : Tensor,
+            %1 : Float(10)):
+        %3 : Tensor = aten::prelu(%0, %1)
+        return (%3))IR";
+
+    auto g = std::make_shared<torch::jit::Graph>();
+    torch::jit::parseIR(graph, &*g);
+
+    auto in = at::randint(-5, 5, {1,10, 1, 1}, {at::kCUDA});
+    auto slope = at::randint(-5, 5, {10}, {at::kCUDA});
+
+    auto params = trtorch::core::conversion::get_named_params(g->inputs(), {slope});
+    auto jit_results = trtorch::tests::util::RunGraph(g, params, {in});
+
+    in = at::clone(in);
+    params = trtorch::core::conversion::get_named_params(g->inputs(), {slope});
+    auto trt_results = trtorch::tests::util::RunGraphEngine(g, params, {in});
+
+    ASSERT_TRUE(trtorch::tests::util::almostEqual(jit_results[0], trt_results[0], 2e-6));
+}
+
+