Remove unused global_state reference from initial_sample_state.

global_state is never used in any of our existing DPQueries, and we don't have any compelling use case.

PiperOrigin-RevId: 255480537

privacy/analysis/privacy_ledger.py

@@ -226,9 +226,9 @@ class QueryWithLedger(dp_query.DPQuery):
     """See base class."""
     return self._query.derive_sample_params(global_state)
 
-  def initial_sample_state(self, global_state, template):
+  def initial_sample_state(self, template):
     """See base class."""
-    return self._query.initial_sample_state(global_state, template)
+    return self._query.initial_sample_state(template)
 
   def preprocess_record(self, params, record):
     """See base class."""

privacy/dp_query/dp_query.py

@@ -88,11 +88,10 @@ class DPQuery(object):
     return ()
 
   @abc.abstractmethod
-  def initial_sample_state(self, global_state, template):
+  def initial_sample_state(self, template):
     """Returns an initial state to use for the next sample.
 
     Args:
-      global_state: The current global state.
       template: A nested structure of tensors, TensorSpecs, or numpy arrays used
         as a template to create the initial sample state. It is assumed that the
         leaves of the structure are python scalars or some type that has
@@ -216,8 +215,7 @@ def zeros_like(arg):
 class SumAggregationDPQuery(DPQuery):
   """Base class for DPQueries that aggregate via sum."""
 
-  def initial_sample_state(self, global_state, template):
-    del global_state  # unused.
+  def initial_sample_state(self, template):
     return nest.map_structure(zeros_like, template)
 
   def accumulate_preprocessed_record(self, sample_state, preprocessed_record):

privacy/dp_query/gaussian_query.py

@@ -69,7 +69,7 @@ class GaussianSumQuery(dp_query.SumAggregationDPQuery):
   def derive_sample_params(self, global_state):
     return global_state.l2_norm_clip
 
-  def initial_sample_state(self, global_state, template):
+  def initial_sample_state(self, template):
     return nest.map_structure(
         dp_query.zeros_like, template)
 

privacy/dp_query/gaussian_query_test.py

@@ -99,7 +99,7 @@ class GaussianQueryTest(tf.test.TestCase, parameterized.TestCase):
       query = gaussian_query.GaussianSumQuery(l2_norm_clip=10.0, stddev=1.0)
       global_state = query.initial_global_state()
       params = query.derive_sample_params(global_state)
-      sample_state = query.initial_sample_state(global_state, records[0])
+      sample_state = query.initial_sample_state(records[0])
       for record in records:
         sample_state = query.accumulate_record(params, sample_state, record)
       return sample_state

privacy/dp_query/nested_query.py

@@ -73,9 +73,9 @@ class NestedQuery(dp_query.DPQuery):
     """See base class."""
     return self._map_to_queries('derive_sample_params', global_state)
 
-  def initial_sample_state(self, global_state, template):
+  def initial_sample_state(self, template):
     """See base class."""
-    return self._map_to_queries('initial_sample_state', global_state, template)
+    return self._map_to_queries('initial_sample_state', template)
 
   def preprocess_record(self, params, record):
     """See base class."""

privacy/dp_query/no_privacy_query.py

@@ -45,11 +45,9 @@ class NoPrivacyAverageQuery(dp_query.SumAggregationDPQuery):
   Accumulates vectors and normalizes by the total number of accumulated vectors.
   """
 
-  def initial_sample_state(self, global_state, template):
+  def initial_sample_state(self, template):
     """See base class."""
-    return (
-        super(NoPrivacyAverageQuery, self).initial_sample_state(
-            global_state, template),
+    return (super(NoPrivacyAverageQuery, self).initial_sample_state(template),
             tf.constant(0.0))
 
   def preprocess_record(self, params, record, weight=1):

privacy/dp_query/normalized_query.py

@@ -68,11 +68,10 @@ class NormalizedQuery(dp_query.DPQuery):
     """See base class."""
     return self._numerator.derive_sample_params(global_state.numerator_state)
 
-  def initial_sample_state(self, global_state, template):
+  def initial_sample_state(self, template):
     """See base class."""
     # NormalizedQuery has no sample state beyond the numerator state.
-    return self._numerator.initial_sample_state(
-        global_state.numerator_state, template)
+    return self._numerator.initial_sample_state(template)
 
   def preprocess_record(self, params, record):
     return self._numerator.preprocess_record(params, record)

privacy/dp_query/quantile_adaptive_clip_sum_query.py

@@ -144,12 +144,11 @@ class QuantileAdaptiveClipSumQuery(dp_query.DPQuery):
         global_state.clipped_fraction_state)
     return self._SampleParams(sum_params, clipped_fraction_params)
 
-  def initial_sample_state(self, global_state, template):
+  def initial_sample_state(self, template):
     """See base class."""
-    sum_state = self._sum_query.initial_sample_state(
-        global_state.sum_state, template)
+    sum_state = self._sum_query.initial_sample_state(template)
     clipped_fraction_state = self._clipped_fraction_query.initial_sample_state(
-        global_state.clipped_fraction_state, tf.constant(0.0))
+        tf.constant(0.0))
     return self._SampleState(sum_state, clipped_fraction_state)
 
   def preprocess_record(self, params, record):

privacy/dp_query/test_utils.py

@@ -38,7 +38,7 @@ def run_query(query, records, global_state=None, weights=None):
   if not global_state:
     global_state = query.initial_global_state()
   params = query.derive_sample_params(global_state)
-  sample_state = query.initial_sample_state(global_state, next(iter(records)))
+  sample_state = query.initial_sample_state(next(iter(records)))
   if weights is None:
     for record in records:
       sample_state = query.accumulate_record(params, sample_state, record)

privacy/optimizers/dp_optimizer.py

@@ -95,8 +95,7 @@ def make_optimizer_class(cls):
           self._num_microbatches = tf.shape(vector_loss)[0]
           if isinstance(self._dp_sum_query, privacy_ledger.QueryWithLedger):
             self._dp_sum_query.set_batch_size(self._num_microbatches)
-        sample_state = self._dp_sum_query.initial_sample_state(
-            self._global_state, var_list)
+        sample_state = self._dp_sum_query.initial_sample_state(var_list)
         microbatches_losses = tf.reshape(vector_loss,
                                          [self._num_microbatches, -1])
         sample_params = (
@@ -162,8 +161,7 @@ def make_optimizer_class(cls):
               tf.trainable_variables() + tf.get_collection(
                   tf.GraphKeys.TRAINABLE_RESOURCE_VARIABLES))
 
-        sample_state = self._dp_sum_query.initial_sample_state(
-            self._global_state, var_list)
+        sample_state = self._dp_sum_query.initial_sample_state(var_list)
 
         if self._unroll_microbatches:
           for idx in range(self._num_microbatches):