Add multiprecision for adadelta op (#50131)

paddle/fluid/operators/optimizers/adadelta_op.cc

@@ -39,12 +39,17 @@ class AdadeltaOpMaker : public framework::OpProtoAndCheckerMaker {
     AddInput("AvgSquaredGrad", "(Tensor) Input average of squared gradient");
     AddInput("AvgSquaredUpdate",
              "(Tensor) Input average of squared parameter updates");
+    AddInput("MasterParam", "FP32 master weight for AMP.").AsDispensable();
 
     AddOutput("ParamOut", "(Tensor) Output parameter");
     AddOutput("AvgSquaredGradOut",
               "(Tensor) Output average of squared gradient");
     AddOutput("AvgSquaredUpdateOut",
               "(Tensor) Output average of squared parameter updates");
+    AddOutput("MasterParamOut",
+              "The updated FP32 master weight for AMP. "
+              "It shared memory with Input(MasterParam).")
+        .AsDispensable();
 
     AddAttr<float>("rho",
                    "(float, default 0.95) Exponential decay rate "
@@ -54,6 +59,10 @@ class AdadeltaOpMaker : public framework::OpProtoAndCheckerMaker {
                    "(float, default 1.0e-6) Constant for "
                    "numerical stability")
         .SetDefault(1.0e-6f);
+    AddAttr<bool>("multi_precision",
+                  "(bool, default false) "
+                  "Whether to use multi-precision during weight updating.")
+        .SetDefault(false);
     AddComment(R"DOC(
 Adadelta Optimizer.
 

paddle/fluid/pybind/eager_generator.h

@@ -206,6 +206,8 @@ std::map<std::string, std::set<std::string>> op_ins_map = {
      {"Q", "K", "V", "Offset", "Columns", "KeyPaddingMask", "AttnMask"}},
     {"sgd", {"Param", "LearningRate", "Grad", "MasterParam"}},
     {"adagrad", {"Param", "Grad", "Moment", "LearningRate", "MasterParam"}},
+    {"adadelta",
+     {"Param", "Grad", "AvgSquaredGrad", "AvgSquaredUpdate", "MasterParam"}},
     {"graph_khop_sampler", {"Row", "Eids", "Col_Ptr", "X"}},
     {"nce",
      {"Input",
@@ -311,6 +313,11 @@ std::map<std::string, std::set<std::string>> op_outs_map = {
       "SavedMean",
       "SavedVariance",
       "ReserveSpace"}},
+    {"adadelta",
+     {"ParamOut",
+      "AvgSquaredGradOut",
+      "AvgSquaredUpdateOut",
+      "MasterParamOut"}},
     {"unique", {"Out", "Index", "Indices", "Counts"}},
     {"unique_consecutive", {"Out", "Index", "Counts"}},
     {"generate_proposals", {"RpnRois", "RpnRoiProbs", "RpnRoisNum"}},
@@ -400,7 +407,11 @@ std::map<std::string, std::set<std::string>> op_passing_outs_map = {
       "MeanGradOut",
       "MasterParamOut"}},
     {"ftrl", {"ParamOut", "SquaredAccumOut", "LinearAccumOut"}},
-    {"adadelta", {"ParamOut", "AvgSquaredGradOut", "AvgSquaredUpdateOut"}},
+    {"adadelta",
+     {"ParamOut",
+      "AvgSquaredGradOut",
+      "AvgSquaredUpdateOut",
+      "MasterParamOut"}},
     {"adagrad", {"ParamOut", "MomentOut", "MasterParamOut"}},
     {"adamax", {"ParamOut", "MomentOut", "InfNormOut"}},
     {"dpsgd", {"ParamOut"}},

paddle/phi/api/yaml/legacy_ops.yaml

@@ -20,13 +20,15 @@
     data_type : x
 
 - op : adadelta_
-  args : (Tensor param, Tensor grad, Tensor avg_squared_grad, Tensor avg_squared_update, float rho, float epsilon)
-  output : Tensor(param_out), Tensor(moment_out), Tensor(inf_norm_out)
+  args : (Tensor param, Tensor grad, Tensor avg_squared_grad, Tensor avg_squared_update, Tensor master_param, float rho, float epsilon, bool multi_precision)
+  output : Tensor(param_out), Tensor(moment_out), Tensor(inf_norm_out), Tensor(master_param_out)
   infer_meta :
     func : AdadeltaInferMeta
   kernel :
     func : adadelta
-  inplace : (param -> param_out), (avg_squared_grad -> moment_out), (avg_squared_update -> inf_norm_out)
+    data_type : param
+  optional : master_param
+  inplace : (param -> param_out), (avg_squared_grad -> moment_out), (avg_squared_update -> inf_norm_out), (master_param -> master_param_out)
 
 - op : adagrad_
   args : (Tensor param, Tensor grad, Tensor moment, Tensor learning_rate, Tensor master_param, float epsilon, bool multi_precision)

paddle/phi/infermeta/multiary.cc

@@ -38,11 +38,14 @@ void AdadeltaInferMeta(const MetaTensor& param,
                        const MetaTensor& grad,
                        const MetaTensor& avg_squared_grad,
                        const MetaTensor& avg_squared_update,
+                       const MetaTensor& master_param,
                        float rho,
                        float epsilon,
+                       bool multi_precision,
                        MetaTensor* param_out,
                        MetaTensor* avg_squared_grad_out,
-                       MetaTensor* avg_squared_update_out) {
+                       MetaTensor* avg_squared_update_out,
+                       MetaTensor* master_param_out) {
   auto param_dims = param.dims();
   PADDLE_ENFORCE_EQ(
       param_dims,

paddle/phi/infermeta/multiary.h

@@ -43,11 +43,14 @@ void AdadeltaInferMeta(const MetaTensor& param,
                        const MetaTensor& grad,
                        const MetaTensor& avg_squared_grad,
                        const MetaTensor& avg_squared_update,
+                       const MetaTensor& master_param,
                        float rho,
                        float epsilon,
+                       bool multi_precision,
                        MetaTensor* param_out,
                        MetaTensor* avg_squared_grad_out,
-                       MetaTensor* avg_squared_update_out);
+                       MetaTensor* avg_squared_update_out,
+                       MetaTensor* master_param_outs);
 
 void AdagradInferMeta(const MetaTensor& param,
                       const MetaTensor& grad,

paddle/phi/kernels/adadelta_kernel.h

@@ -24,10 +24,13 @@ void AdadeltaKernel(const Context& dev_ctx,
                     const DenseTensor& grad,
                     const DenseTensor& avg_squared_grad,
                     const DenseTensor& avg_squared_update,
+                    const paddle::optional<DenseTensor>& master_param,
                     float rho,
                     float epsilon,
+                    bool multi_precision,
                     DenseTensor* param_out,
                     DenseTensor* avg_squared_grad_out,
-                    DenseTensor* avg_squared_update_out);
+                    DenseTensor* avg_squared_update_out,
+                    DenseTensor* master_param_outs);
 
 }  // namespace phi

paddle/phi/kernels/gpu/adadelta_kernel.cu

@@ -18,5 +18,10 @@
 #include "paddle/phi/core/kernel_registry.h"
 #include "paddle/phi/kernels/impl/adadelta_kernel_impl.h"
 
-PD_REGISTER_KERNEL(
-    adadelta, GPU, ALL_LAYOUT, phi::AdadeltaKernel, float, double) {}
+PD_REGISTER_KERNEL(adadelta,
+                   GPU,
+                   ALL_LAYOUT,
+                   phi::AdadeltaKernel,
+                   float,
+                   double,
+                   phi::dtype::float16) {}

paddle/phi/kernels/impl/adadelta_kernel_impl.h

@@ -14,6 +14,7 @@
 
 #pragma once
 
+#include "paddle/phi/common/amp_type_traits.h"
 #include "paddle/phi/kernels/adadelta_kernel.h"
 #include "paddle/phi/kernels/funcs/eigen/common.h"
 #include "paddle/phi/kernels/funcs/eigen/eigen_function.h"
@@ -26,40 +27,58 @@ void AdadeltaKernel(const Context& dev_ctx,
                     const DenseTensor& grad,
                     const DenseTensor& avg_squared_grad,
                     const DenseTensor& avg_squared_update,
+                    const paddle::optional<DenseTensor>& master_param,
                     float rho,
                     float epsilon,
+                    bool multi_precision,
                     DenseTensor* param_out,
                     DenseTensor* avg_squared_grad_out,
-                    DenseTensor* avg_squared_update_out) {
+                    DenseTensor* avg_squared_update_out,
+                    DenseTensor* master_param_outs) {
+  using MPDType = typename phi::dtype::template MPTypeTrait<T>::Type;
   dev_ctx.template Alloc<T>(param_out);
-  dev_ctx.template Alloc<T>(avg_squared_grad_out);
-  dev_ctx.template Alloc<T>(avg_squared_update_out);
+  dev_ctx.template Alloc<MPDType>(avg_squared_grad_out);
+  dev_ctx.template Alloc<MPDType>(avg_squared_update_out);
 
-  T rho_ = static_cast<T>(rho);
-  T epsilon_ = static_cast<T>(epsilon);
+  MPDType rho_ = static_cast<MPDType>(rho);
+  MPDType epsilon_ = static_cast<MPDType>(epsilon);
 
   auto eigen_param = EigenVector<T>::Flatten(param);
   auto eigen_grad = EigenVector<T>::Flatten(grad);
   // Squared gradient accumulator
-  auto eigen_avg_squared_grad = EigenVector<T>::Flatten(avg_squared_grad);
+  auto eigen_avg_squared_grad = EigenVector<MPDType>::Flatten(avg_squared_grad);
   // Squared updates accumulator
-  auto eigen_avg_squared_update = EigenVector<T>::Flatten(avg_squared_update);
+  auto eigen_avg_squared_update =
+      EigenVector<MPDType>::Flatten(avg_squared_update);
   auto eigen_param_out = EigenVector<T>::Flatten(*param_out);
   auto eigen_avg_squared_grad_out =
-      EigenVector<T>::Flatten(*avg_squared_grad_out);
+      EigenVector<MPDType>::Flatten(*avg_squared_grad_out);
   auto eigen_avg_squared_update_out =
-      EigenVector<T>::Flatten(*avg_squared_update_out);
+      EigenVector<MPDType>::Flatten(*avg_squared_update_out);
   auto& place = *dev_ctx.eigen_device();
 
+  auto eigen_grad_cast = eigen_grad.template cast<MPDType>();
+
   eigen_avg_squared_grad_out.device(place) =
-      rho_ * eigen_avg_squared_grad + (1 - rho_) * eigen_grad.square();
+      rho_ * eigen_avg_squared_grad + (1 - rho_) * eigen_grad_cast.square();
   auto update = -((eigen_avg_squared_update + epsilon_) /
                   (eigen_avg_squared_grad_out + epsilon_))
                      .sqrt() *
-                eigen_grad;
+                eigen_grad_cast;
   eigen_avg_squared_update_out.device(place) =
       rho_ * eigen_avg_squared_update + (1 - rho_) * update.square();
-  eigen_param_out.device(place) = eigen_param + update;
+
+  if (multi_precision) {
+    auto eigen_master_param_out =
+        EigenVector<MPDType>::Flatten(*master_param_outs);
+    auto eigen_master_param = EigenVector<MPDType>::Flatten(*master_param);
+
+    eigen_master_param_out.device(place) = eigen_master_param + update;
+    eigen_param_out.device(place) =
+        (eigen_param.template cast<MPDType>() + update).template cast<T>();
+  } else {
+    eigen_param_out.device(place) = eigen_param + update.template cast<T>();
+  }
 }
 
 }  // namespace phi

paddle/phi/kernels/xpu/adadelta_kernel.cc

@@ -25,11 +25,14 @@ void AdadeltaKernel(const Context& dev_ctx,
                     const DenseTensor& grad,
                     const DenseTensor& avg_squared_grad,
                     const DenseTensor& avg_squared_update,
+                    const paddle::optional<DenseTensor>& master_param,
                     float rho,
                     float epsilon,
+                    bool multi_precision,
                     DenseTensor* param_out,
                     DenseTensor* avg_squared_grad_out,
-                    DenseTensor* avg_squared_update_out) {
+                    DenseTensor* avg_squared_update_out,
+                    DenseTensor* master_param_outs) {
   dev_ctx.template Alloc<T>(param_out);
   dev_ctx.template Alloc<T>(avg_squared_grad_out);
   dev_ctx.template Alloc<T>(avg_squared_update_out);

paddle/phi/ops/compat/adadelta_sig.cc

+// Copyright (c) 2023 PaddlePaddle 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.
+// 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.
+
+#include "paddle/phi/core/compat/op_utils.h"
+
+namespace phi {
+
+KernelSignature AdadeltaOpArgumentMapping(const ArgumentMappingContext& ctx) {
+  if (ctx.IsDenseTensorInput("Grad")) {
+    return KernelSignature(
+        "adadelta",
+        {"Param", "Grad", "AvgSquaredGrad", "AvgSquaredUpdate", "MasterParam"},
+        {"rho", "epsilon", "multi_precision"},
+        {"ParamOut",
+         "AvgSquaredGradOut",
+         "AvgSquaredUpdateOut",
+         "MasterParamOut"});
+  }
+
+  return KernelSignature("unregistered", {}, {}, {});
+}
+
+}  // namespace phi
+
+PD_REGISTER_ARG_MAPPING_FN(adadelta, phi::AdadeltaOpArgumentMapping);

python/paddle/fluid/optimizer.py

@@ -3181,14 +3181,87 @@ class AdadeltaOptimizer(Optimizer):
             name=name,
         )
         self.type = "adadelta"
+        self._multi_precision = False
+        self._master_weights = {}
         self._epsilon = epsilon
         self._rho = rho
 
+    def _create_master_weight(self, param):
+        if param.name in self._master_weights:
+            var = self._master_weights[param.name]
+        else:
+            assert isinstance(self.helper, LayerHelper)
+
+            var_name = param.name + '_fp32_master'
+            var_name = unique_name.generate(var_name)
+            var = paddle.static.create_global_var(
+                name=var_name,
+                shape=param.shape,
+                value=0,
+                dtype='float32',
+                persistable=True,
+            )
+            block = self.helper.startup_program.global_block()
+            block.append_op(
+                type="cast",
+                inputs={"X": [param]},
+                outputs={"Out": [var]},
+                attrs={
+                    "in_dtype": param.dtype,
+                    "out_dtype": core.VarDesc.VarType.FP32,
+                },
+            )
+            self._master_weights[param.name] = var
+        return var
+
+    def _get_accumulator(self, name, param):
+        """Utility function to fetch an accumulator for a parameter
+        Args:
+            name: name of the accumulator
+            param: parameter variable for which accumulator is to be fetched
+        Returns:
+            accumulator variable for the parameter
+        """
+        if self._name is not None:
+            name = self._name + "_" + name
+        find_master = (
+            self._multi_precision and param.dtype == core.VarDesc.VarType.FP16
+        )
+        target_param = (
+            self._master_weights[param.name] if find_master else param
+        )
+        target_name = target_param.name
+        if (
+            name not in self._accumulators
+            or target_name not in self._accumulators[name]
+        ):
+            raise Exception(
+                "Accumulator {} does not exist for parameter {}".format(
+                    name, target_name
+                )
+            )
+        return self._accumulators[name][target_name]
+
     def _create_accumulators(self, block, parameters):
         if not isinstance(block, framework.Block):
             raise TypeError("block is not instance of framework.Block.")
 
         for p in parameters:
+            if self._multi_precision and p.dtype == core.VarDesc.VarType.FP16:
+                master_p = self._create_master_weight(p)
+                self._add_accumulator(self._avg_squared_grad_acc_str, master_p)
+                self._add_accumulator(
+                    self._avg_squared_update_acc_str, master_p
+                )
+                continue
+            if (
+                p.dtype == core.VarDesc.VarType.FP16
+                and not self._multi_precision
+            ):
+                warnings.warn(
+                    "Accumulating with FP16 in optimizer can lead to poor accuracy or slow convergence."
+                    "Consider using multi_precision=True option of the Lars optimizer."
+                )
             self._add_accumulator(self._avg_squared_grad_acc_str, p)
             self._add_accumulator(self._avg_squared_update_acc_str, p)
 
@@ -3202,6 +3275,15 @@ class AdadeltaOptimizer(Optimizer):
         avg_squared_update_acc = self._get_accumulator(
             self._avg_squared_update_acc_str, param_and_grad[0]
         )
+        find_master = (
+            self._multi_precision
+            and param_and_grad[0].dtype == core.VarDesc.VarType.FP16
+        )
+        master_weight = (
+            self._master_weights[param_and_grad[0].name]
+            if find_master
+            else None
+        )
 
         if in_dygraph_mode():
             _C_ops.adadelta_(
@@ -3209,25 +3291,38 @@ class AdadeltaOptimizer(Optimizer):
                 param_and_grad[1],
                 avg_squared_grad_acc,
                 avg_squared_update_acc,
+                master_weight,
                 self._rho,
                 self._epsilon,
+                find_master,
             )
         else:
             # Create the adadelta optimizer op
+            inputs = {
+                "Param": param_and_grad[0],
+                "Grad": param_and_grad[1],
+                "AvgSquaredGrad": avg_squared_grad_acc,
+                "AvgSquaredUpdate": avg_squared_update_acc,
+            }
+            outputs = {
+                "ParamOut": param_and_grad[0],
+                "AvgSquaredGradOut": avg_squared_grad_acc,
+                "AvgSquaredUpdateOut": avg_squared_update_acc,
+            }
+
+            if find_master:
+                inputs["MasterParam"] = master_weight
+                outputs["MasterParamOut"] = master_weight
+
             adadelta_op = block.append_op(
                 type=self.type,
-                inputs={
-                    "Param": param_and_grad[0],
-                    "Grad": param_and_grad[1],
-                    "AvgSquaredGrad": avg_squared_grad_acc,
-                    "AvgSquaredUpdate": avg_squared_update_acc,
-                },
-                outputs={
-                    "ParamOut": param_and_grad[0],
-                    "AvgSquaredGradOut": avg_squared_grad_acc,
-                    "AvgSquaredUpdateOut": avg_squared_update_acc,
+                inputs=inputs,
+                outputs=outputs,
+                attrs={
+                    "epsilon": self._epsilon,
+                    "rho": self._rho,
+                    "multi_precision": find_master,
                 },
-                attrs={"epsilon": self._epsilon, "rho": self._rho},
                 stop_gradient=True,
             )
 

python/paddle/fluid/tests/unittests/test_adadelta_op.py

@@ -203,5 +203,281 @@ class TestAdadeltaV2Group(TestAdadeltaV2):
         adam.clear_gradients()
 
 
+class TestAdadeltaOpMultiPrecison(unittest.TestCase):
+    def _test_adadelta_op_dygraph_place_amp(self, place, use_amp=False):
+        import paddle
+
+        paddle.disable_static()
+        paddle.seed(10)
+        paddle.set_device(place)
+        input = paddle.randn((5, 5))
+
+        model = paddle.nn.Linear(5, 5)
+        optimizer = paddle.optimizer.Adadelta(
+            learning_rate=0.01,
+            parameters=model.parameters(),
+            weight_decay=0.1,
+        )
+
+        optimizer._multi_precision = use_amp
+
+        for idx in range(2):
+            if place == 'gpu' and use_amp:
+                model = paddle.amp.decorate(models=model, level='O2')
+                scaler = paddle.amp.GradScaler(init_loss_scaling=1024)
+
+            if place == 'gpu' and use_amp:
+                with paddle.amp.auto_cast(level='O2'):
+                    output = model(input)
+                    loss = paddle.mean(output)
+                scaled = scaler.scale(loss)
+                scaled.backward()
+                scaler.step(optimizer)
+                optimizer.clear_grad()
+            else:
+                output = model(input)
+                loss = paddle.mean(output)
+                loss.backward()
+                optimizer.step()
+                optimizer.clear_grad()
+        paddle.enable_static()
+
+    def _get_places(self):
+        import paddle
+
+        places = ['cpu']
+        if paddle.is_compiled_with_cuda():
+            places.append('gpu')
+        return places
+
+    def test_main(self):
+        for place in self._get_places():
+            use_amp_list = [True, False]
+            for use_amp in use_amp_list:
+                self._test_adadelta_op_dygraph_place_amp(place, use_amp)
+
+
+class TestAdadeltaMultiPrecision2_0(unittest.TestCase):
+    def dygraph_adadelta_mp(self, mp, use_amp):
+        paddle.disable_static()
+        paddle.seed(100)
+        paddle.set_device('gpu')
+        input = paddle.randn((2, 2))
+        model = paddle.nn.Linear(2, 2)
+        optimizer = paddle.optimizer.Adadelta(
+            0.5, parameters=model.parameters()
+        )
+        optimizer._multi_precision = mp
+        if use_amp:
+            model = paddle.amp.decorate(models=model, level='O2')
+            scaler = paddle.amp.GradScaler(init_loss_scaling=1024)
+
+        for idx in range(5):
+            if use_amp:
+                with paddle.amp.auto_cast(level='O2'):
+                    output = model(input)
+                    loss = paddle.mean(output)
+                scaled = scaler.scale(loss)
+                scaled.backward()
+                scaler.minimize(optimizer, scaled)
+                optimizer.clear_grad()
+            else:
+                output = model(input)
+                loss = paddle.mean(output)
+                loss.backward()
+                optimizer.step()
+                optimizer.clear_grad()
+
+        return output, model.parameters()
+
+    def static_adadelta_mp(self, mp, use_amp):
+        paddle.enable_static()
+        paddle.seed(100)
+        np.random.seed(100)
+        exe = paddle.static.Executor('gpu')
+        train_program = paddle.static.Program()
+        startup_program = paddle.static.Program()
+        optimizer = paddle.optimizer.Adadelta(0.1)
+        optimizer._multi_precision = mp
+
+        if use_amp:
+            optimizer = paddle.static.amp.decorate(
+                optimizer,
+                init_loss_scaling=128.0,
+                use_dynamic_loss_scaling=True,
+                use_pure_fp16=True,
+                use_fp16_guard=False,
+            )
+        with paddle.static.program_guard(train_program, startup_program):
+            if use_amp:
+                data = paddle.static.data(
+                    shape=[2, 2], name='X', dtype='float16'
+                )
+            else:
+                data = paddle.static.data(
+                    shape=[2, 2], name='X', dtype='float32'
+                )
+            hidden = paddle.static.nn.fc(x=data, size=10)
+            loss = paddle.mean(hidden)
+            optimizer.minimize(loss)
+        exe.run(startup_program)
+
+        if use_amp:
+            optimizer.amp_init(place='gpu', scope=paddle.static.global_scope())
+            x = np.random.random(size=(2, 2)).astype('float16')
+        else:
+            x = np.random.random(size=(2, 2)).astype('float32')
+        out = []
+        for idx in range(5):
+            (loss_data,) = exe.run(
+                train_program, feed={"X": x}, fetch_list=[loss.name]
+            )
+            out.append(loss_data)
+        return out
+
+    def test_main(self):
+        if not paddle.is_compiled_with_cuda():
+            return
+        "Test dygraph mode"
+        output1_dy, params1_dy = self.dygraph_adadelta_mp(use_amp=True, mp=True)
+        output2_dy, params2_dy = self.dygraph_adadelta_mp(
+            use_amp=False, mp=False
+        )
+        np.testing.assert_allclose(
+            output1_dy.astype('float32').numpy(),
+            output2_dy.astype('float32').numpy(),
+            rtol=1e-05,
+            atol=0.1,
+        )
+        for idx in range(len(params1_dy)):
+            np.testing.assert_allclose(
+                params1_dy[idx].astype('float32').numpy(),
+                params2_dy[idx].astype('float32').numpy(),
+                rtol=1e-05,
+                atol=0.1,
+            )
+        "Test static mode"
+        output1_st = self.static_adadelta_mp(use_amp=True, mp=True)
+        output2_st = self.static_adadelta_mp(use_amp=False, mp=False)
+        for idx in range(len(output1_st)):
+            np.testing.assert_allclose(
+                output1_st[idx].astype('float32'),
+                output2_st[idx].astype('float32'),
+                rtol=1e-05,
+                atol=0.1,
+            )
+
+
+class TestAdadeltaMultiPrecision1_0(unittest.TestCase):
+    def dygraph_adadelta_mp(self, use_amp, mp):
+        paddle.disable_static()
+        paddle.seed(10)
+        paddle.set_device('gpu')
+        input = paddle.randn((2, 2))
+        model = paddle.nn.Linear(2, 2)
+        optimizer = paddle.fluid.optimizer.Adadelta(
+            learning_rate=0.001,
+            parameter_list=model.parameters(),
+        )
+        optimizer._multi_precision = mp
+        if use_amp:
+            model = paddle.amp.decorate(models=model, level='O2')
+            scaler = paddle.amp.GradScaler(init_loss_scaling=1024)
+
+        for idx in range(5):
+            if use_amp:
+                with paddle.amp.auto_cast(level='O2'):
+                    output = model(input)
+                    loss = paddle.mean(output)
+                scaled = scaler.scale(loss)
+                scaled.backward()
+                scaler.minimize(optimizer, scaled)
+                optimizer.clear_gradients()
+            else:
+                output = model(input)
+                loss = paddle.mean(output)
+                optimizer.minimize(loss)
+                optimizer.clear_gradients()
+
+        return output, model.parameters()
+
+    def static_adadelta_mp(self, use_amp, mp):
+        paddle.enable_static()
+        paddle.seed(100)
+        np.random.seed(100)
+        exe = paddle.static.Executor('gpu')
+        train_program = paddle.static.Program()
+        startup_program = paddle.static.Program()
+        optimizer = paddle.fluid.optimizer.Adadelta(learning_rate=0.001)
+        optimizer._multi_precision = mp
+
+        if use_amp:
+            optimizer = paddle.static.amp.decorate(
+                optimizer,
+                init_loss_scaling=128.0,
+                use_dynamic_loss_scaling=True,
+                use_pure_fp16=True,
+                use_fp16_guard=False,
+            )
+        with paddle.static.program_guard(train_program, startup_program):
+            if use_amp:
+                data = paddle.static.data(
+                    shape=[2, 2], name='X', dtype='float16'
+                )
+            else:
+                data = paddle.static.data(
+                    shape=[2, 2], name='X', dtype='float32'
+                )
+            hidden = paddle.static.nn.fc(x=data, size=10)
+            loss = paddle.mean(hidden)
+            optimizer.minimize(loss)
+        exe.run(startup_program)
+
+        if use_amp:
+            optimizer.amp_init(place='gpu', scope=paddle.static.global_scope())
+            x = np.random.random(size=(2, 2)).astype('float16')
+        else:
+            x = np.random.random(size=(2, 2)).astype('float32')
+        out = []
+        for idx in range(5):
+            (loss_data,) = exe.run(
+                train_program, feed={"X": x}, fetch_list=[loss.name]
+            )
+            out.append(loss_data)
+        return out
+
+    def test_main(self):
+        if not paddle.is_compiled_with_cuda():
+            return
+        "Test dygraph mode"
+        output1_dy, params1_dy = self.dygraph_adadelta_mp(use_amp=True, mp=True)
+        output2_dy, params2_dy = self.dygraph_adadelta_mp(
+            use_amp=False, mp=False
+        )
+        np.testing.assert_allclose(
+            output1_dy.astype('float32').numpy(),
+            output2_dy.astype('float32').numpy(),
+            rtol=1e-05,
+            atol=0.1,
+        )
+        for idx in range(len(params1_dy)):
+            np.testing.assert_allclose(
+                params1_dy[idx].astype('float32').numpy(),
+                params2_dy[idx].astype('float32').numpy(),
+                rtol=1e-05,
+                atol=0.1,
+            )
+        "Test static mode"
+        output1_st = self.static_adadelta_mp(use_amp=True, mp=True)
+        output2_st = self.static_adadelta_mp(use_amp=False, mp=False)
+        for idx in range(len(output1_st)):
+            np.testing.assert_allclose(
+                output1_st[idx].astype('float32'),
+                output2_st[idx].astype('float32'),
+                rtol=1e-05,
+                atol=0.1,
+            )
+
+
 if __name__ == "__main__":
     unittest.main()

python/paddle/optimizer/adadelta.py

@@ -12,10 +12,14 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import warnings
+
+import paddle
 from paddle import _C_ops
 
-from ..fluid import framework
+from ..fluid import core, framework, unique_name
 from ..fluid.dygraph import no_grad
+from ..fluid.layer_helper import LayerHelper
 from ..framework import in_dygraph_mode
 from .optimizer import Optimizer
 
@@ -130,6 +134,8 @@ class Adadelta(Optimizer):
             grad_clip=grad_clip,
             name=name,
         )
+        self._multi_precision = False
+        self._master_weights = {}
         self.type = "adadelta"
         self._epsilon = epsilon
         self._rho = rho
@@ -138,6 +144,62 @@ class Adadelta(Optimizer):
             'rho': rho,
         }
 
+    def _create_master_weight(self, param):
+        if param.name in self._master_weights:
+            var = self._master_weights[param.name]
+        else:
+            assert isinstance(self.helper, LayerHelper)
+
+            var_name = param.name + "_fp32_master"
+            var_name = unique_name.generate(var_name)
+            var = paddle.static.create_global_var(
+                name=var_name,
+                shape=param.shape,
+                value=0,
+                dtype='float32',
+                persistable=True,
+            )
+            block = self.helper.startup_program.global_block()
+            block.append_op(
+                type="cast",
+                inputs={"X": [param]},
+                outputs={"Out": [var]},
+                attrs={
+                    "in_dtype": param.dtype,
+                    "out_dtype": core.VarDesc.VarType.FP32,
+                },
+            )
+            self._master_weights[param.name] = var
+        return var
+
+    def _get_accumulator(self, name, param):
+        """Utility function to fetch an accumulator for a parameter
+        Args:
+            name: name of the accumulator
+            param: parameter variable for which accumulator is to be fetched
+        Returns:
+            accumulator variable for the parameter
+        """
+        if self._name is not None:
+            name = self._name + "_" + name
+        find_master = (
+            self._multi_precision and param.dtype == core.VarDesc.VarType.FP16
+        )
+        target_param = (
+            self._master_weights[param.name] if find_master else param
+        )
+        target_name = target_param.name
+        if (
+            name not in self._accumulators
+            or target_name not in self._accumulators[name]
+        ):
+            raise Exception(
+                "Accumulator {} does not exist for parameter {}".format(
+                    name, target_name
+                )
+            )
+        return self._accumulators[name][target_name]
+
     def _create_accumulators(self, block, parameters):
         if not isinstance(block, framework.Block):
             raise TypeError("block is not instance of framework.Block.")
@@ -145,6 +207,21 @@ class Adadelta(Optimizer):
             parameters = parameters.get('params')
 
         for p in parameters:
+            if self._multi_precision and p.dtype == core.VarDesc.VarType.FP16:
+                master_p = self._create_master_weight(p)
+                self._add_accumulator(self._avg_squared_grad_acc_str, master_p)
+                self._add_accumulator(
+                    self._avg_squared_update_acc_str, master_p
+                )
+                continue
+            if (
+                p.dtype == core.VarDesc.VarType.FP16
+                and not self._multi_precision
+            ):
+                warnings.warn(
+                    "Accumulating with FP16 in optimizer can lead to poor accuracy or slow convergence."
+                    "Consider using multi_precision=True option of the Lars optimizer."
+                )
             self._add_accumulator(self._avg_squared_grad_acc_str, p)
             self._add_accumulator(self._avg_squared_update_acc_str, p)
 
@@ -158,6 +235,15 @@ class Adadelta(Optimizer):
         avg_squared_update_acc = self._get_accumulator(
             self._avg_squared_update_acc_str, param_and_grad[0]
         )
+        find_master = (
+            self._multi_precision
+            and param_and_grad[0].dtype == core.VarDesc.VarType.FP16
+        )
+        master_weight = (
+            self._master_weights[param_and_grad[0].name]
+            if find_master
+            else None
+        )
 
         if in_dygraph_mode():
             with no_grad():
@@ -166,8 +252,10 @@ class Adadelta(Optimizer):
                     param_and_grad[1],
                     avg_squared_grad_acc,
                     avg_squared_update_acc,
+                    master_weight,
                     self._rho,
                     self._epsilon,
+                    find_master,
                 )
             return None
         else:
@@ -175,20 +263,29 @@ class Adadelta(Optimizer):
                 raise TypeError("block is not instance of framework.Block.")
 
             # Create the adadelta optimizer op
+            inputs = {
+                "Param": param_and_grad[0],
+                "Grad": param_and_grad[1],
+                "AvgSquaredGrad": avg_squared_grad_acc,
+                "AvgSquaredUpdate": avg_squared_update_acc,
+            }
+            outputs = {
+                "ParamOut": param_and_grad[0],
+                "AvgSquaredGradOut": avg_squared_grad_acc,
+                "AvgSquaredUpdateOut": avg_squared_update_acc,
+            }
+            if find_master:
+                inputs["MasterParam"] = master_weight
+                outputs["MasterParamOut"] = master_weight
             adadelta_op = block.append_op(
                 type=self.type,
-                inputs={
-                    "Param": param_and_grad[0],
-                    "Grad": param_and_grad[1],
-                    "AvgSquaredGrad": avg_squared_grad_acc,
-                    "AvgSquaredUpdate": avg_squared_update_acc,
-                },
-                outputs={
-                    "ParamOut": param_and_grad[0],
-                    "AvgSquaredGradOut": avg_squared_grad_acc,
-                    "AvgSquaredUpdateOut": avg_squared_update_acc,
+                inputs=inputs,
+                outputs=outputs,
+                attrs={
+                    "epsilon": self._epsilon,
+                    "rho": self._rho,
+                    "multi_precision": find_master,
                 },
-                attrs={"epsilon": self._epsilon, "rho": self._rho},
                 stop_gradient=True,
             )