Add indirection layer for selecting cmath functions from global namespace.

There can be functions beyond round() that aren't present within the std::
namespace depending on libstdc++ version. This CL adds an indirection layer
using a new TF_MICRO_USE_GLOBAL_CMATH_FUNCTIONS flag to select these functions
and converts TfLiteRound() to use this layer.

Other similar indirections will be added in future CLs.

PiperOrigin-RevId: 303425632
Change-Id: Idfe14924329827f71742ab6aedfd6ead9bcb0dbb

tensorflow/lite/kernels/BUILD

@@ -379,8 +379,8 @@ cc_library(
     copts = tflite_copts() + micro_copts(),
     deps = [
         "//tensorflow/lite/c:common",
+        "//tensorflow/lite/kernels/internal:cppmath",
         "//tensorflow/lite/kernels/internal:quantization_util",
-        "//tensorflow/lite/kernels/internal:round",
         "@flatbuffers",
     ],
 )

tensorflow/lite/kernels/internal/BUILD

@@ -243,7 +243,7 @@ cc_library(
         ":strided_slice_logic",
         ":types",
         ":reference_base",
-        ":round",
+        ":cppmath",
         ":tensor",
         ":tensor_utils",
         ":transpose_utils",
@@ -294,7 +294,7 @@ cc_library(
         ":types",
         ":legacy_types",
         ":legacy_reference_base",
-        ":round",
+        ":cppmath",
         "//third_party/eigen3",
         "@gemmlowp",
         "//tensorflow/lite/c:common",
@@ -346,9 +346,10 @@ cc_test(
 )
 
 cc_library(
-    name = "round",
+    name = "cppmath",
     srcs = [],
-    hdrs = ["round.h"],
+    hdrs = ["cppmath.h"],
+    build_for_embedded = True,
     copts = tflite_copts(),
 )
 
@@ -359,7 +360,7 @@ cc_library(
     copts = tflite_copts() + micro_copts(),
     deps = [
         ":compatibility",
-        ":round",
+        ":cppmath",
         ":types",
         "//tensorflow/lite/kernels:op_macros",
     ],
@@ -467,7 +468,7 @@ cc_library(
         ":common",
         ":compatibility",
         ":quantization_util",
-        ":round",
+        ":cppmath",
         ":strided_slice_logic",
         ":tensor",
         ":tensor_utils",
@@ -532,7 +533,7 @@ cc_library(
         ":common",
         ":compatibility",
         ":quantization_util",
-        ":round",
+        ":cppmath",
         ":strided_slice_logic",
         ":legacy_types",
         ":tensor",
@@ -600,7 +601,7 @@ cc_library(
     deps = [
         ":common",
         ":compatibility",
-        ":round",
+        ":cppmath",
         "//tensorflow/lite:minimal_logging",
         "//tensorflow/lite/c:common",
         "//tensorflow/lite/kernels:cpu_backend_context",
@@ -621,9 +622,9 @@ cc_library(
     deps = [
         ":common",
         ":compatibility",
+        ":cppmath",
         ":cpu_check",
         ":portable_tensor_utils",
-        ":round",
         "//tensorflow/lite/c:common",
         "//tensorflow/lite/experimental/ruy",
         "//tensorflow/lite/experimental/ruy:detect_arm",

tensorflow/lite/kernels/internal/cppmath.h

@@ -1,4 +1,4 @@
-/* Copyright 2017 The TensorFlow Authors. All Rights Reserved.
+/* Copyright 2020 The TensorFlow Authors. 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.
@@ -12,29 +12,28 @@ 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.
 ==============================================================================*/
-#ifndef TENSORFLOW_LITE_KERNELS_INTERNAL_ROUND_H_
-#define TENSORFLOW_LITE_KERNELS_INTERNAL_ROUND_H_
+#ifndef TENSORFLOW_LITE_KERNELS_INTERNAL_CPPMATH_H_
+#define TENSORFLOW_LITE_KERNELS_INTERNAL_CPPMATH_H_
 
 #include <cmath>
 
 namespace tflite {
 
-// TODO(aselle): See if we can do this only on jdk. Also mikecase, check
-// if you need this for java host build.
-#if defined(TF_LITE_USE_GLOBAL_ROUND) || \
+#if defined(TF_LITE_USE_GLOBAL_CMATH_FUNCTIONS) || \
     (defined(__ANDROID__) && !defined(__NDK_MAJOR__)) || defined(ARDUINO)
-template <class T>
-inline float TfLiteRound(const float x) {
-  return ::round(x);
-}
-inline double TfLiteRound(const double x) { return ::round(x); }
+#define TF_LITE_GLOBAL_STD_PREFIX
 #else
-template <class T>
-inline T TfLiteRound(const T x) {
-  return std::round(x);
-}
+#define TF_LITE_GLOBAL_STD_PREFIX std
 #endif
 
+#define DECLARE_STD_GLOBAL_SWITCH1(tf_name, std_name) \
+  template <class T>                                  \
+  inline T tf_name(const T x) {                       \
+    return TF_LITE_GLOBAL_STD_PREFIX::std_name(x);    \
+  }
+
+DECLARE_STD_GLOBAL_SWITCH1(TfLiteRound, round);
+
 }  // namespace tflite
 
-#endif  // TENSORFLOW_LITE_KERNELS_INTERNAL_ROUND_H_
+#endif  // TENSORFLOW_LITE_KERNELS_INTERNAL_CPPMATH_H_

tensorflow/lite/kernels/internal/optimized/batch_matmul.h

@@ -19,7 +19,6 @@ limitations under the License.
 #include "tensorflow/lite/kernels/cpu_backend_gemm.h"
 #include "tensorflow/lite/kernels/cpu_backend_gemm_params.h"
 #include "tensorflow/lite/kernels/internal/common.h"
-#include "tensorflow/lite/kernels/internal/round.h"
 #include "tensorflow/lite/kernels/internal/types.h"
 
 namespace tflite {

tensorflow/lite/kernels/internal/optimized/integer_ops/pooling.h

@@ -29,12 +29,12 @@ limitations under the License.
 
 #include "fixedpoint/fixedpoint.h"
 #include "tensorflow/lite/experimental/ruy/profiler/instrumentation.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 #include "tensorflow/lite/kernels/internal/optimized/cpu_check.h"
 #include "tensorflow/lite/kernels/internal/optimized/im2col_utils.h"
 #include "tensorflow/lite/kernels/internal/quantization_util.h"
 #include "tensorflow/lite/kernels/internal/reference/integer_ops/pooling.h"
 #include "tensorflow/lite/kernels/internal/reference/reference_ops.h"
-#include "tensorflow/lite/kernels/internal/round.h"
 #include "tensorflow/lite/kernels/internal/strided_slice_logic.h"
 #include "tensorflow/lite/kernels/internal/tensor_utils.h"
 #include "tensorflow/lite/kernels/internal/types.h"

tensorflow/lite/kernels/internal/optimized/neon_tensor_utils.cc

@@ -30,9 +30,9 @@ limitations under the License.
 #include "tensorflow/lite/kernels/cpu_backend_gemm_params.h"
 #include "tensorflow/lite/kernels/internal/common.h"
 #include "tensorflow/lite/kernels/internal/compatibility.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 #include "tensorflow/lite/kernels/internal/optimized/cpu_check.h"
 #include "tensorflow/lite/kernels/internal/optimized/neon_tensor_utils_impl.h"
-#include "tensorflow/lite/kernels/internal/round.h"
 
 #ifdef USE_NEON
 

tensorflow/lite/kernels/internal/optimized/optimized_ops.h

@@ -44,11 +44,11 @@ limitations under the License.
 #include "tensorflow/lite/kernels/cpu_backend_gemm.h"
 #include "tensorflow/lite/kernels/cpu_backend_gemm_params.h"
 #include "tensorflow/lite/kernels/cpu_backend_threadpool.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 #include "tensorflow/lite/kernels/internal/optimized/cpu_check.h"
 #include "tensorflow/lite/kernels/internal/optimized/im2col_utils.h"
 #include "tensorflow/lite/kernels/internal/quantization_util.h"
 #include "tensorflow/lite/kernels/internal/reference/reference_ops.h"
-#include "tensorflow/lite/kernels/internal/round.h"
 #include "tensorflow/lite/kernels/internal/strided_slice_logic.h"
 #include "tensorflow/lite/kernels/internal/tensor.h"
 #include "tensorflow/lite/kernels/internal/tensor_utils.h"

tensorflow/lite/kernels/internal/optimized/sparse_ops/fully_connected.h

@@ -17,8 +17,8 @@ limitations under the License.
 
 #include "tensorflow/lite/c/common.h"
 #include "tensorflow/lite/kernels/internal/common.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 #include "tensorflow/lite/kernels/internal/quantization_util.h"
-#include "tensorflow/lite/kernels/internal/round.h"
 #include "tensorflow/lite/kernels/internal/types.h"
 
 namespace tflite {

tensorflow/lite/kernels/internal/quantization_util.cc

@@ -13,13 +13,14 @@ See the License for the specific language governing permissions and
 limitations under the License.
 ==============================================================================*/
 
+#include "tensorflow/lite/kernels/internal/quantization_util.h"
+
 #include <algorithm>
 #include <cmath>
 #include <limits>
 
 #include "tensorflow/lite/kernels/internal/compatibility.h"
-#include "tensorflow/lite/kernels/internal/quantization_util.h"
-#include "tensorflow/lite/kernels/internal/round.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 
 namespace tflite {
 

tensorflow/lite/kernels/internal/quantization_util.h

@@ -20,7 +20,7 @@ limitations under the License.
 #include <limits>
 
 #include "tensorflow/lite/kernels/internal/compatibility.h"
-#include "tensorflow/lite/kernels/internal/round.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 #include "tensorflow/lite/kernels/internal/types.h"
 
 namespace tflite {

tensorflow/lite/kernels/internal/reference/batch_matmul.h

@@ -17,7 +17,6 @@ limitations under the License.
 
 #include "tensorflow/lite/c/common.h"
 #include "tensorflow/lite/kernels/internal/common.h"
-#include "tensorflow/lite/kernels/internal/round.h"
 #include "tensorflow/lite/kernels/internal/types.h"
 
 namespace tflite {

tensorflow/lite/kernels/internal/reference/concatenation.h

@@ -18,7 +18,7 @@ limitations under the License.
 
 #include "tensorflow/lite/kernels/internal/common.h"
 #include "tensorflow/lite/kernels/internal/compatibility.h"
-#include "tensorflow/lite/kernels/internal/round.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 #include "tensorflow/lite/kernels/internal/types.h"
 
 namespace tflite {

tensorflow/lite/kernels/internal/reference/fully_connected.h

@@ -16,8 +16,8 @@ limitations under the License.
 #define TENSORFLOW_LITE_KERNELS_INTERNAL_REFERENCE_FULLY_CONNECTED_H_
 
 #include "tensorflow/lite/kernels/internal/common.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 #include "tensorflow/lite/kernels/internal/quantization_util.h"
-#include "tensorflow/lite/kernels/internal/round.h"
 #include "tensorflow/lite/kernels/internal/types.h"
 
 namespace tflite {

tensorflow/lite/kernels/internal/reference/logistic.h

@@ -19,8 +19,8 @@ limitations under the License.
 
 #include "fixedpoint/fixedpoint.h"
 #include "tensorflow/lite/kernels/internal/common.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 #include "tensorflow/lite/kernels/internal/quantization_util.h"
-#include "tensorflow/lite/kernels/internal/round.h"
 #include "tensorflow/lite/kernels/internal/types.h"
 #include "tensorflow/lite/kernels/op_macros.h"
 

tensorflow/lite/kernels/internal/reference/pooling.h

@@ -16,8 +16,8 @@ limitations under the License.
 #define TENSORFLOW_LITE_KERNELS_INTERNAL_REFERENCE_POOLING_H_
 
 #include "tensorflow/lite/kernels/internal/common.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 #include "tensorflow/lite/kernels/internal/quantization_util.h"
-#include "tensorflow/lite/kernels/internal/round.h"
 #include "tensorflow/lite/kernels/internal/types.h"
 
 namespace tflite {

tensorflow/lite/kernels/internal/reference/portable_tensor_utils.cc

@@ -24,8 +24,8 @@ limitations under the License.
 #include "tensorflow/lite/kernels/cpu_backend_context.h"
 #include "tensorflow/lite/kernels/internal/common.h"
 #include "tensorflow/lite/kernels/internal/compatibility.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 #include "tensorflow/lite/kernels/internal/reference/portable_tensor_utils_impl.h"
-#include "tensorflow/lite/kernels/internal/round.h"
 
 #if defined(_MSC_VER)
 #define __restrict__ __restrict

tensorflow/lite/kernels/internal/reference/quantize.h

@@ -16,7 +16,7 @@ limitations under the License.
 #define TENSORFLOW_LITE_KERNELS_INTERNAL_REFERENCE_QUANTIZE_H_
 
 #include "tensorflow/lite/kernels/internal/common.h"
-#include "tensorflow/lite/kernels/internal/round.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 #include "tensorflow/lite/kernels/internal/types.h"
 
 namespace tflite {

tensorflow/lite/kernels/internal/reference/reduce.h

@@ -17,6 +17,7 @@ limitations under the License.
 
 #include "tensorflow/lite/experimental/ruy/profiler/instrumentation.h"
 #include "tensorflow/lite/kernels/internal/common.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 #include "tensorflow/lite/kernels/internal/quantization_util.h"
 #include "tensorflow/lite/kernels/internal/types.h"
 
@@ -371,7 +372,7 @@ inline bool QuantizedMeanOrSum(const T* input_data, int32 input_zero_point,
           -input_zero_point * scale * num_elements_in_axis + 0.5f;
       for (size_t idx = 0; idx < num_outputs; ++idx) {
         const U value =
-            static_cast<U>(std::round(temp_sum[idx] * scale + bias)) +
+            static_cast<U>(TfLiteRound(temp_sum[idx] * scale + bias)) +
             output_zero_point;
         output_data[idx] = static_cast<T>(value);
       }
@@ -381,7 +382,7 @@ inline bool QuantizedMeanOrSum(const T* input_data, int32 input_zero_point,
         float float_mean = static_cast<float>(temp_sum[idx]) /
                            static_cast<float>(num_elements_in_axis);
         float result =
-            std::min(std::round(float_mean * scale + bias) + output_zero_point,
+            std::min(TfLiteRound(float_mean * scale + bias) + output_zero_point,
                      static_cast<float>(std::numeric_limits<T>::max()));
         result =
             std::max(result, static_cast<float>(std::numeric_limits<T>::min()));

tensorflow/lite/kernels/internal/reference/reference_ops.h

@@ -57,7 +57,6 @@ limitations under the License.
 #include "tensorflow/lite/kernels/internal/reference/softmax.h"
 #include "tensorflow/lite/kernels/internal/reference/strided_slice.h"
 #include "tensorflow/lite/kernels/internal/reference/sub.h"
-#include "tensorflow/lite/kernels/internal/round.h"
 #include "tensorflow/lite/kernels/internal/strided_slice_logic.h"
 #include "tensorflow/lite/kernels/internal/tensor.h"
 #include "tensorflow/lite/kernels/internal/types.h"

tensorflow/lite/kernels/internal/reference/softmax.h

@@ -19,8 +19,8 @@ limitations under the License.
 
 #include "fixedpoint/fixedpoint.h"
 #include "tensorflow/lite/kernels/internal/common.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 #include "tensorflow/lite/kernels/internal/quantization_util.h"
-#include "tensorflow/lite/kernels/internal/round.h"
 #include "tensorflow/lite/kernels/internal/types.h"
 #include "tensorflow/lite/kernels/op_macros.h"
 

tensorflow/lite/kernels/kernel_util.cc

@@ -18,8 +18,8 @@ limitations under the License.
 #include <cmath>
 #include <memory>
 
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 #include "tensorflow/lite/kernels/internal/quantization_util.h"
-#include "tensorflow/lite/kernels/internal/round.h"
 
 namespace tflite {
 

tensorflow/lite/micro/kernels/BUILD

@@ -506,7 +506,10 @@ tflite_micro_cc_test(
 cc_library(
     name = "activation_utils",
     hdrs = ["activation_utils.h"],
-    deps = ["//tensorflow/lite/c:common"],
+    deps = [
+        "//tensorflow/lite/c:common",
+        "//tensorflow/lite/kernels/internal:cppmath",
+    ],
 )
 
 tflite_micro_cc_test(

tensorflow/lite/micro/kernels/activation_utils.h

@@ -16,9 +16,11 @@ limitations under the License.
 #ifndef TENSORFLOW_LITE_MICRO_KERNELS_ACTIVATION_UTILS_H_
 #define TENSORFLOW_LITE_MICRO_KERNELS_ACTIVATION_UTILS_H_
 
+#include <algorithm>
 #include <cmath>
 
 #include "tensorflow/lite/c/builtin_op_data.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 
 namespace tflite {
 namespace ops {
@@ -30,11 +32,11 @@ inline float ActivationValFloat(TfLiteFusedActivation act, float a) {
     case kTfLiteActNone:
       return a;
     case kTfLiteActRelu:
-      return std::fmax(0.0f, a);
+      return std::max(0.0f, a);
     case kTfLiteActRelu1:
-      return std::fmax(-1.0f, std::fmin(a, 1.0f));
+      return std::max(-1.0f, std::min(a, 1.0f));
     case kTfLiteActRelu6:
-      return std::fmax(0.0f, std::fmin(a, 6.0f));
+      return std::max(0.0f, std::min(a, 6.0f));
     case kTfLiteActTanh:
       return std::tanh(a);
     case kTfLiteActSignBit:

tensorflow/lite/micro/tools/make/Makefile

@@ -165,7 +165,7 @@ tensorflow/lite/kernels/internal/reference/sub.h \
 tensorflow/lite/kernels/internal/reference/logistic.h \
 tensorflow/lite/kernels/internal/reference/strided_slice.h \
 tensorflow/lite/kernels/internal/reference/integer_ops/pooling.h \
-tensorflow/lite/kernels/internal/round.h \
+tensorflow/lite/kernels/internal/cppmath.h \
 tensorflow/lite/kernels/internal/strided_slice_logic.h \
 tensorflow/lite/kernels/internal/tensor.h \
 tensorflow/lite/kernels/internal/tensor_ctypes.h \

tensorflow/lite/micro/tools/make/targets/mcu_riscv_makefile.inc

@@ -14,7 +14,7 @@ ifeq ($(TARGET), riscv32_mcu)
     -fno-builtin-printf \
     -fno-exceptions \
     -DTF_LITE_MCU_DEBUG_LOG \
-    -DTF_LITE_USE_GLOBAL_ROUND \
+    -DTF_LITE_USE_GLOBAL_CMATH_FUNCTIONS \
     -fno-unwind-tables \
     -fno-builtin \
     -ffunction-sections \

tensorflow/lite/tools/optimize/BUILD

@@ -108,8 +108,8 @@ cc_library(
         "//tensorflow/lite:minimal_logging",
         "//tensorflow/lite/c:common",
         "//tensorflow/lite/core/api",
+        "//tensorflow/lite/kernels/internal:cppmath",
         "//tensorflow/lite/kernels/internal:quantization_util",
-        "//tensorflow/lite/kernels/internal:round",
         "//tensorflow/lite/kernels/internal:tensor_utils",
         "//tensorflow/lite/kernels/internal:types",
         "//tensorflow/lite/schema:schema_fbs",

tensorflow/lite/tools/optimize/quantization_utils.cc

@@ -23,8 +23,8 @@ limitations under the License.
 #include "third_party/eigen3/Eigen/Core"
 #include "tensorflow/lite/c/common.h"
 #include "tensorflow/lite/core/api/error_reporter.h"
+#include "tensorflow/lite/kernels/internal/cppmath.h"
 #include "tensorflow/lite/kernels/internal/quantization_util.h"
-#include "tensorflow/lite/kernels/internal/round.h"
 #include "tensorflow/lite/kernels/internal/tensor_utils.h"
 #include "tensorflow/lite/kernels/internal/types.h"
 #include "tensorflow/lite/minimal_logging.h"