diff --git a/b_asic/operation.py b/b_asic/operation.py
index a0d0f48a1f7429ce0d393ad4e93ef24c84914f7b..ecc471371182017ade2d9244e59e70af211c9ac3 100644
--- a/b_asic/operation.py
+++ b/b_asic/operation.py
@@ -180,6 +180,13 @@ class Operation(GraphComponent, SignalSourceProvider):
"""
raise NotImplementedError
+ @abstractmethod
+ def depends(self, output_index: int, input_index: int) -> bool:
+ """Check if the output at the given output index depends on the input at the
+ given input index in order to be evaluated.
+ """
+ raise NotImplementedError
+
class AbstractOperation(Operation, AbstractGraphComponent):
"""Generic abstract operation class which most implementations will derive from.
@@ -340,6 +347,13 @@ class AbstractOperation(Operation, AbstractGraphComponent):
pass
return [self]
+ def depends(self, output_index: int, input_index: int) -> bool:
+ if output_index < 0 or output_index >= self.output_count:
+ raise IndexError(f"Output index out of range (expected 0-{self.output_count - 1}, got {output_index})")
+ if input_index < 0 or input_index >= self.input_count:
+ raise IndexError(f"Input index out of range (expected 0-{self.input_count - 1}, got {input_index})")
+ return True # By default, assume each output depends on all inputs.
+
@property
def neighbors(self) -> Iterable[GraphComponent]:
return list(self.input_signals) + list(self.output_signals)
diff --git a/b_asic/signal_flow_graph.py b/b_asic/signal_flow_graph.py
index e8e7af01ab93fdba948d9ff7ec19078b3b71dee6..3395466805273d39fbcab5aa2809f0905d1d80da 100644
--- a/b_asic/signal_flow_graph.py
+++ b/b_asic/signal_flow_graph.py
@@ -3,7 +3,7 @@ B-ASIC Signal Flow Graph Module.
TODO: More info.
"""
-from typing import List, Iterable, Sequence, Dict, Optional, DefaultDict, Set
+from typing import List, Iterable, Sequence, Dict, Optional, DefaultDict, MutableSet
from numbers import Number
from collections import defaultdict, deque
@@ -45,7 +45,7 @@ class SFG(AbstractOperation):
_graph_id_generator: GraphIDGenerator
_input_operations: List[Input]
_output_operations: List[Output]
- _original_components_to_new: Set[GraphComponent]
+ _original_components_to_new: MutableSet[GraphComponent]
_original_input_signals_to_indices: Dict[Signal, int]
_original_output_signals_to_indices: Dict[Signal, int]
@@ -233,6 +233,13 @@ class SFG(AbstractOperation):
def split(self) -> Iterable[Operation]:
return self.operations
+
+ def depends(self, output_index: int, input_index: int) -> bool:
+ if output_index < 0 or output_index >= self.output_count:
+ raise IndexError(f"Output index out of range (expected 0-{self.output_count - 1}, got {output_index})")
+ if input_index < 0 or input_index >= self.input_count:
+ raise IndexError(f"Input index out of range (expected 0-{self.input_count - 1}, got {input_index})")
+ return self._source_depends(self._output_operations[output_index].input(0).signals[0].source, self._input_operations[input_index], set())
def copy_component(self, *args, **kwargs) -> GraphComponent:
return super().copy_component(*args, **kwargs, inputs = self._input_operations, outputs = self._output_operations,
@@ -385,3 +392,15 @@ class SFG(AbstractOperation):
value = src.operation.evaluate_output(src.index, input_values, results, registers, src_prefix)
results[key] = value
return value
+
+ def _source_depends(self, src: OutputPort, input_operation: Input, visited: MutableSet[Operation]) -> bool:
+ if src.operation is input_operation:
+ return True
+
+ if src.operation not in visited:
+ visited.add(src.operation)
+ for i, port in enumerate(src.operation.inputs):
+ if src.operation.depends(src.index, i):
+ if self._source_depends(port.signals[0].source, input_operation, visited):
+ return True
+ return False
\ No newline at end of file
diff --git a/test/fixtures/signal_flow_graph.py b/test/fixtures/signal_flow_graph.py
index 0a6c554d1340478dad25a11655f0542bf6fba1d1..e196f1f26323c28fcf0673e36cfc53783d371b63 100644
--- a/test/fixtures/signal_flow_graph.py
+++ b/test/fixtures/signal_flow_graph.py
@@ -29,6 +29,33 @@ def sfg_two_inputs_two_outputs():
out2 = Output(add2)
return SFG(inputs = [in1, in2], outputs = [out1, out2])
+@pytest.fixture
+def sfg_two_inputs_two_outputs_independent():
+ """Valid SFG with two inputs and two outputs, where the first output only depends
+ on the first input and the second output only depends on the second input.
+ . .
+ in1-------------------->out1
+ . .
+ . .
+ . c1--+ .
+ . | .
+ . v .
+ in2------+ add1---->out2
+ . | ^ .
+ . | | .
+ . +------+ .
+ . .
+ out1 = in1
+ out2 = in2 + 3
+ """
+ in1 = Input()
+ in2 = Input()
+ c1 = Constant(3)
+ add1 = in2 + c1
+ out1 = Output(in1)
+ out2 = Output(add1)
+ return SFG(inputs = [in1, in2], outputs = [out1, out2])
+
@pytest.fixture
def sfg_nested():
"""Valid SFG with two inputs and one output.
diff --git a/test/test_depends.py b/test/test_depends.py
new file mode 100644
index 0000000000000000000000000000000000000000..16efcaeab0049856aa796bd9e86cf0799070c77a
--- /dev/null
+++ b/test/test_depends.py
@@ -0,0 +1,26 @@
+from b_asic import Addition, Butterfly
+
+class TestDepends:
+ def test_depends_addition(self):
+ add1 = Addition()
+ assert add1.depends(0, 0) == True
+ assert add1.depends(0, 1) == True
+
+ def test_depends_butterfly(self):
+ bfly1 = Butterfly()
+ assert bfly1.depends(0, 0) == True
+ assert bfly1.depends(0, 1) == True
+ assert bfly1.depends(1, 0) == True
+ assert bfly1.depends(1, 1) == True
+
+ def test_depends_sfg(self, sfg_two_inputs_two_outputs):
+ assert sfg_two_inputs_two_outputs.depends(0, 0) == True
+ assert sfg_two_inputs_two_outputs.depends(0, 1) == True
+ assert sfg_two_inputs_two_outputs.depends(1, 0) == True
+ assert sfg_two_inputs_two_outputs.depends(1, 1) == True
+
+ def test_depends_sfg_independent(self, sfg_two_inputs_two_outputs_independent):
+ assert sfg_two_inputs_two_outputs_independent.depends(0, 0) == True
+ assert sfg_two_inputs_two_outputs_independent.depends(0, 1) == False
+ assert sfg_two_inputs_two_outputs_independent.depends(1, 0) == False
+ assert sfg_two_inputs_two_outputs_independent.depends(1, 1) == True
\ No newline at end of file