From 0916c404a081488945ea28d12de129e63829f5d1 Mon Sep 17 00:00:00 2001
From: Lukas Geiger <lukas.geiger94@gmail.com>
Date: Mon, 4 May 2020 23:58:45 +0100
Subject: [PATCH 1/2] Mark QuantizationSpec methods that don't change member
 data as constant

---
 .../compiler/mlir/lite/quantization/quantization_config.h     | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tensorflow/compiler/mlir/lite/quantization/quantization_config.h b/tensorflow/compiler/mlir/lite/quantization/quantization_config.h
index 5b1c73e7887..ea59f49f5b7 100644
--- a/tensorflow/compiler/mlir/lite/quantization/quantization_config.h
+++ b/tensorflow/compiler/mlir/lite/quantization/quantization_config.h
@@ -84,7 +84,7 @@ struct QuantizationSpecs {
   bool RunWeightQuantization() const { return weight_quantization; }
 
   // Whether this inference type represents a signed storage type.
-  bool IsSignedInferenceType() {
+  bool IsSignedInferenceType() const {
     switch (inference_type) {
       case tensorflow::DT_QUINT8:
       case tensorflow::DT_QUINT16:
@@ -96,7 +96,7 @@ struct QuantizationSpecs {
 
   // Gets the width of this quantization type. Returns 0 if it isn't a
   // quantization type.
-  int64_t GetQuantizationTypeWidth() {
+  int64_t GetQuantizationTypeWidth() const {
     switch (inference_type) {
       case tensorflow::DT_QINT8:
       case tensorflow::DT_QUINT8:

From a5ae7f124b27f97a35de9b3778f98e2bcc62a10f Mon Sep 17 00:00:00 2001
From: Lukas Geiger <lukas.geiger94@gmail.com>
Date: Tue, 5 May 2020 00:03:05 +0100
Subject: [PATCH 2/2] Respect inference type in DefaultQuantParamsPass

---
 tensorflow/compiler/mlir/lite/tf_tfl_passes.cc |  3 ++-
 .../lite/transforms/default_quant_params.cc    | 18 ++++++++++++------
 .../compiler/mlir/lite/transforms/passes.h     |  2 +-
 3 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/tensorflow/compiler/mlir/lite/tf_tfl_passes.cc b/tensorflow/compiler/mlir/lite/tf_tfl_passes.cc
index 5eefa821c6b..8dbc84d1a9f 100644
--- a/tensorflow/compiler/mlir/lite/tf_tfl_passes.cc
+++ b/tensorflow/compiler/mlir/lite/tf_tfl_passes.cc
@@ -48,7 +48,8 @@ void AddQuantizationPasses(const mlir::TFL::QuantizationSpecs& quant_specs,
       quant_specs.default_ranges.second.hasValue()) {
     pass_manager->addPass(mlir::TFL::CreateDefaultQuantParamsPass(
         quant_specs.default_ranges.first.getValueOr(0.0),
-        quant_specs.default_ranges.second.getValueOr(0.0)));
+        quant_specs.default_ranges.second.getValueOr(0.0),
+        quant_specs.IsSignedInferenceType()));
     pass_manager->addPass(mlir::TFL::CreateQuantizePass());
     pass_manager->addPass(
         mlir::TFL::CreatePostQuantizePass(emit_quant_adaptor_ops));
diff --git a/tensorflow/compiler/mlir/lite/transforms/default_quant_params.cc b/tensorflow/compiler/mlir/lite/transforms/default_quant_params.cc
index a1602baced5..c23ae9fcfab 100644
--- a/tensorflow/compiler/mlir/lite/transforms/default_quant_params.cc
+++ b/tensorflow/compiler/mlir/lite/transforms/default_quant_params.cc
@@ -46,8 +46,11 @@ namespace {
 class DefaultQuantParamsPass
     : public PassWrapper<DefaultQuantParamsPass, FunctionPass> {
  public:
-  explicit DefaultQuantParamsPass(double default_min, double default_max)
-      : default_min_(default_min), default_max_(default_max) {}
+  explicit DefaultQuantParamsPass(double default_min, double default_max,
+                                  bool is_signed)
+      : default_min_(default_min),
+        default_max_(default_max),
+        is_signed_(is_signed) {}
 
   void runOnFunction() override;
 
@@ -82,6 +85,7 @@ class DefaultQuantParamsPass
 
   double default_min_;
   double default_max_;
+  bool is_signed_;
   quant::QuantParams default_quant_params_;
 };
 }  // namespace
@@ -214,15 +218,16 @@ quant::QuantParams DefaultQuantParamsPass::GetDefaultQuantParams(
     default_quant_params_ = quant::fakeQuantAttrsToType(
         builder.getUnknownLoc(),
         /*numBits=*/8, default_min_, default_max_, /*narrowRange=*/false,
-        builder.getF32Type());
+        builder.getF32Type(), is_signed_);
   }
   return default_quant_params_;
 }
 
 // Creates an instance of the default quant parameters pass.
 std::unique_ptr<OperationPass<FuncOp>> CreateDefaultQuantParamsPass(
-    double default_min, double default_max) {
-  return absl::make_unique<DefaultQuantParamsPass>(default_min, default_max);
+    double default_min, double default_max, bool is_signed) {
+  return absl::make_unique<DefaultQuantParamsPass>(default_min, default_max,
+                                                   is_signed);
 }
 
 // Registers this pass with default values, only for test
@@ -230,7 +235,8 @@ static PassRegistration<DefaultQuantParamsPass> pass(
     "tfl-default-quant",
     "Apply quantization with default quantization parameter", [] {
       return CreateDefaultQuantParamsPass(/*default_min=*/-1.0,
-                                          /*default_max=*/1.0);
+                                          /*default_max=*/1.0,
+                                          /*is_signed=*/false);
     });
 
 }  // namespace TFL
diff --git a/tensorflow/compiler/mlir/lite/transforms/passes.h b/tensorflow/compiler/mlir/lite/transforms/passes.h
index 959c17e317a..105c9394fb4 100644
--- a/tensorflow/compiler/mlir/lite/transforms/passes.h
+++ b/tensorflow/compiler/mlir/lite/transforms/passes.h
@@ -76,7 +76,7 @@ std::unique_ptr<OperationPass<ModuleOp>> CreateOptimizeFunctionalOpsPass();
 // Creates an instance of the TensorFlow Lite dialect pass to add default
 // quantization parameters.
 std::unique_ptr<OperationPass<FuncOp>> CreateDefaultQuantParamsPass(
-    double default_min, double default_max);
+    double default_min, double default_max, bool is_signed);
 
 // Creates an instance of the TensorFlow Lite dialect pass to convert dense
 // tensor to sparse format.