Sync from upstream TF.

Author: TFLM-bot

tensorflow/lite/core/c/common.cc

@@ -649,4 +649,12 @@ TfLiteRunStep TfLiteTensorGetShapeKnownStep(const TfLiteTensor* t) {
   return kTfLiteRunStepUnknown;
 }
 
+// Returns a sentinel value to be used as the user_data field of a TfLiteNode
+// when the kernel initialization fails.
+void* TfLiteKernelInitFailed() {
+  static const char dummy_object = 0;
+  const void* sentinel = &dummy_object;
+  return const_cast<void*>(sentinel);
+}
+
 }  // extern "C"

tensorflow/lite/core/c/common.h

@@ -1161,6 +1161,11 @@ typedef struct TfLiteRegistration {
   /// NOTE: if the data is already in the desired format, simply implement this
   /// function to return `nullptr` and implement the free function to be a
   /// no-op.
+  ///
+  /// NOTE: For a Delegate kernel, returns `TfLiteKernelInitFailed()` if it
+  /// fails on the initialization. This eventually causes user's API call to
+  /// InterpreterBuilder::operator() or Interpreter::ModifyGraphWithDelegate()
+  /// to return an error.
   void* (*init)(TfLiteContext* context, const char* buffer, size_t length);
 
   /// The pointer `buffer` is the data previously returned by an init
@@ -1499,6 +1504,10 @@ TfLiteRunStep TfLiteTensorGetDataKnownStep(const TfLiteTensor* t);
 /// operations.
 TfLiteRunStep TfLiteTensorGetShapeKnownStep(const TfLiteTensor* t);
 
+/// Returns a sentinel value to be used as the user_data field of a TfLiteNode
+/// when the kernel initialization fails.
+void* TfLiteKernelInitFailed();
+
 /** @} */
 // Ends `\addtogroup`, it's important for the doc generator that this doesn't
 // include the CC code below.

tensorflow/lite/kernels/internal/portable_tensor_utils.h

@@ -170,6 +170,7 @@ inline void BatchQuantizeFloats(const float* float_data_ptr, int n_batch,
       tensor_utils::SymmetricQuantizeFloats(
           float_data_ptr + offset, n_data, quantized_data_ptr + offset,
           &unused_min, &unused_max, &scaling_factors[b]);
+      if (zero_points) zero_points[b] = 0;
     }
   }
 }