Update functionality of --allow_nudging_weights_to_use_fast_gemm_kernel.

PiperOrigin-RevId: 206354203

3 files changed, 19 insertions, 3 deletions

diff --git a/tensorflow/contrib/lite/toco/graph_transformations/ensure_uint8_weights_safe_for_fast_int8_kernels.cc b/tensorflow/contrib/lite/toco/graph_transformations/ensure_uint8_weights_safe_for_fast_int8_kernels.cc
index 75642bbc37..c13fc0de75 100644
--- a/tensorflow/contrib/lite/toco/graph_transformations/ensure_uint8_weights_safe_for_fast_int8_kernels.cc
+++ b/tensorflow/contrib/lite/toco/graph_transformations/ensure_uint8_weights_safe_for_fast_int8_kernels.cc
@@ -181,7 +181,7 @@ bool EnsureUint8WeightsSafeForFastInt8Kernels::Run(Model* model,
         // future without worrying.
         static constexpr int kMinDistanceBetweenBadValues = 16;
         if (distance < kMinDistanceBetweenBadValues) {
-          if (allow_nudging_weights()) {
+          if (allow_nudging_weights() || has_default_ranges_flag()) {
             buffer_data[i] = 1;
             changed = true;
             continue;
@@ -200,6 +200,15 @@ bool EnsureUint8WeightsSafeForFastInt8Kernels::Run(Model* model,
   }
 
   if (changed) {
+    if (has_default_ranges_flag()) {
+      std::cerr
+          << "Since the specified values of --default_ranges_min and "
+             "--default_ranges_max result in values incompatible with TFLite's "
+             "fast int8 kernels, "
+             "--allow_nudging_weights_to_use_fast_gemm_kernel "
+             "has been enabled. This may affect the accuracy of the model."
+          << std::endl;
+    }
     AddMessageF("Tweaked weights values for %s", LogName(op));
   }
 
diff --git a/tensorflow/contrib/lite/toco/graph_transformations/graph_transformations.h b/tensorflow/contrib/lite/toco/graph_transformations/graph_transformations.h
index b7634e28c6..8d9a4c4700 100644
--- a/tensorflow/contrib/lite/toco/graph_transformations/graph_transformations.h
+++ b/tensorflow/contrib/lite/toco/graph_transformations/graph_transformations.h
@@ -262,8 +262,12 @@ class EnsureUint8WeightsSafeForFastInt8Kernels : public GraphTransformation {
   bool allow_nudging_weights() const { return allow_nudging_weights_; }
   void set_allow_nudging_weights(bool val) { allow_nudging_weights_ = val; }
 
+  bool has_default_ranges_flag() const { return has_default_ranges_flag_; }
+  void set_has_default_ranges_flag(bool val) { has_default_ranges_flag_ = val; }
+
  private:
   bool allow_nudging_weights_ = false;
+  bool has_default_ranges_flag_ = false;
 };
 
 #undef DECLARE_GRAPH_TRANSFORMATION
diff --git a/tensorflow/contrib/lite/toco/toco_tooling.cc b/tensorflow/contrib/lite/toco/toco_tooling.cc
index aa7f6996eb..fcd3cbab07 100644
--- a/tensorflow/contrib/lite/toco/toco_tooling.cc
+++ b/tensorflow/contrib/lite/toco/toco_tooling.cc
@@ -309,8 +309,9 @@ void Transform(const TocoFlags& toco_flags, Model* model) {
     // HardcodeMinMax to move changes through the graph as we make changes.
     auto propagate_default_min_max =
         absl::make_unique<PropagateDefaultMinMax>();
-    if (toco_flags.has_default_ranges_min() &&
-        toco_flags.has_default_ranges_max()) {
+    bool has_default_ranges_flag = (toco_flags.has_default_ranges_min() &&
+                                    toco_flags.has_default_ranges_max());
+    if (has_default_ranges_flag) {
       propagate_default_min_max->DefineTypeRange(
           ArrayDataType::kUint8, toco_flags.default_ranges_min(),
           toco_flags.default_ranges_max());
@@ -335,6 +336,8 @@ void Transform(const TocoFlags& toco_flags, Model* model) {
         new EnsureUint8WeightsSafeForFastInt8Kernels;
     ensure_safe_for_int8_kernels->set_allow_nudging_weights(
         toco_flags.allow_nudging_weights_to_use_fast_gemm_kernel());
+    ensure_safe_for_int8_kernels->set_has_default_ranges_flag(
+        has_default_ranges_flag);
     RunGraphTransformations(model, "quantization graph transformations",
                             {
                                 new RemoveTrivialQuantizedActivationFunc,