[WASM] Add FloorDiv used by PoseNet

tfjs-backend-wasm/src/cc/BUILD

@@ -86,6 +86,7 @@ tfjs_cc_library(
     ":CropAndResize",
     ":Conv2D",
     ":DepthwiseConv2dNative",
+    ":FloorDiv",
     ":FusedConv2D",
     ":Div",
     ":Mul",
@@ -213,6 +214,16 @@ tfjs_cc_library(
   ],
 )
 
+tfjs_cc_library(
+  name = "FloorDiv",
+  srcs = ["kernels/FloorDiv.cc"],
+  deps = [
+    ":backend",
+    ":binary",
+    ":util",
+  ],
+)
+
 tfjs_cc_library(
   name = "FusedConv2D",
   srcs = ["kernels/FusedConv2D.cc"],

tfjs-backend-wasm/src/cc/kernels/FloorDiv.cc

@@ -0,0 +1,55 @@
+/* Copyright 2019 Google Inc. All Rights Reserved.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ===========================================================================*/
+
+#ifdef __EMSCRIPTEN__
+#include <emscripten.h>
+#endif
+
+#include <cmath>
+
+#include "src/cc/backend.h"
+#include "src/cc/binary.h"
+#include "src/cc/util.h"
+
+namespace tfjs {
+namespace wasm {
+// We use C-style API to interface with Javascript.
+extern "C" {
+
+#ifdef __EMSCRIPTEN__
+EMSCRIPTEN_KEEPALIVE
+#endif
+void FloorDiv(const int a_id, const int b_id, const DType dtype,
+              const int out_id) {
+  auto& a_info = backend::get_tensor_info(a_id);
+  switch (dtype) {
+    case DType::float32:
+      binary_f32(a_id, b_id, out_id,
+                 [](float a, float b) { return floor(a / b); });
+      break;
+    case DType::int32:
+      binary_i32(a_id, b_id, out_id, [](int a, int b) {
+        return static_cast<int>(floor(static_cast<float>(a) / b));
+      });
+      break;
+    default:
+      util::warn(
+          "FloorDiv for tensor ids %d and %d failed. Unsupported dtype %d",
+          a_id, b_id, dtype);
+  }
+}
+
+}  // extern "C"
+}  // namespace wasm
+}  // namespace tfjs

tfjs-backend-wasm/src/kernels/FloorDiv.ts

@@ -0,0 +1,19 @@
+/**
+ * @license
+ * Copyright 2019 Google Inc. All Rights Reserved.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * =============================================================================
+ */
+
+import {registerBinaryKernel} from './binary_kernel';
+registerBinaryKernel('FloorDiv');

tfjs-backend-wasm/src/kernels/all_kernels.ts

@@ -30,6 +30,7 @@ import './Conv2D';
 import './CropAndResize';
 import './DepthwiseConv2dNative';
 import './Div';
+import './FloorDiv';
 import './FusedBatchNorm';
 import './FusedConv2D';
 import './Max';

tfjs-backend-wasm/src/setup_test.ts

@@ -139,9 +139,8 @@ const TEST_FILTERS: TestFilter[] = [
   {
     include: 'div ',
     excludes: [
-      'gradient',          // Gradient not defined yet.
-      'integer division',  // FloorDiv not yet implemented.
-      'upcasts',           // Cast not supported yet.
+      'gradient',  // Gradient not defined yet.
+      'upcasts',   // Cast not supported yet.
       'broadcasting same rank Tensors different shape',  // Broadcasting along
                                                          // inner dims not
                                                          // supported yet.

tfjs-core/src/ops/binary_ops.ts

@@ -534,13 +534,13 @@ function floorDiv_<T extends Tensor>(
       const tmp = $b.square();
       return res.div(tmp.toFloat()).neg();
     };
-    return {$a: derA, $b: derB};
+    return {a: derA, b: derB};
   };
   return ENGINE.runKernelFunc((backend, save) => {
     const res = backend.floorDiv($a, $b);
     save([$a, $b]);
     return res;
-  }, {$a, $b}, der) as T;
+  }, {a: $a, b: $b}, der, 'FloorDiv') as T;
 }
 
 /**