From b45944b66a034bdb97f688d77958993fc3b9bfb6 Mon Sep 17 00:00:00 2001
From: Arthur Meyre <arthur.meyre@zama.ai>
Date: Wed, 21 Jul 2021 10:41:01 +0200
Subject: [PATCH] dev(ir): add the basis for the frontend IR

- add IntermediateNode base class
- add Add
- add Input
---
 hdk/common/__init__.py                    |  2 +-
 hdk/common/representation/__init__.py     |  2 +
 hdk/common/representation/intermediate.py | 53 +++++++++++++++++++++++
 3 files changed, 56 insertions(+), 1 deletion(-)
 create mode 100644 hdk/common/representation/__init__.py
 create mode 100644 hdk/common/representation/intermediate.py

diff --git a/hdk/common/__init__.py b/hdk/common/__init__.py
index ace1dd1c6..cd563aaf9 100644
--- a/hdk/common/__init__.py
+++ b/hdk/common/__init__.py
@@ -1,2 +1,2 @@
 """HDK's module for shared data structures and code"""
-from . import data_types
+from . import data_types, representation
diff --git a/hdk/common/representation/__init__.py b/hdk/common/representation/__init__.py
new file mode 100644
index 000000000..7bdfcc4df
--- /dev/null
+++ b/hdk/common/representation/__init__.py
@@ -0,0 +1,2 @@
+"""HDK's representation module to represent source programs"""
+from . import intermediate
diff --git a/hdk/common/representation/intermediate.py b/hdk/common/representation/intermediate.py
new file mode 100644
index 000000000..7b1cb5433
--- /dev/null
+++ b/hdk/common/representation/intermediate.py
@@ -0,0 +1,53 @@
+"""File containing HDK's intermdiate representation of source programs operations"""
+
+from abc import ABC
+from copy import deepcopy
+from typing import Any, Dict, Iterable, List, Optional, Tuple
+
+from ..data_types import BaseValue
+
+
+class IntermediateNode(ABC):
+    """Abstract Base Class to derive from to represent source program operations"""
+
+    inputs: List[BaseValue]
+    outputs: List[BaseValue]
+    op_args: Optional[Tuple[Any, ...]]
+    op_kwargs: Optional[Dict[str, Any]]
+
+    def __init__(
+        self,
+        inputs: Iterable[BaseValue],
+        op_args: Optional[Tuple[Any, ...]] = None,
+        op_kwargs: Optional[Dict[str, Any]] = None,
+    ) -> None:
+        self.inputs = list(inputs)
+        self.op_args = op_args
+        self.op_kwargs = op_kwargs
+
+
+class Add(IntermediateNode):
+    """Addition between two values"""
+
+    def __init__(
+        self,
+        inputs: Iterable[BaseValue],
+    ) -> None:
+        super().__init__(inputs)
+        assert len(self.inputs) == 2
+
+        # For now copy the first input type for the output type
+        # We don't perform checks or enforce consistency here for now, so this is OK
+        self.outputs = [deepcopy(self.inputs[0])]
+
+
+class Input(IntermediateNode):
+    """Node representing an input of the numpy program"""
+
+    def __init__(
+        self,
+        inputs: Iterable[BaseValue],
+    ) -> None:
+        super().__init__(inputs)
+        assert len(self.inputs) == 1
+        self.outputs = [deepcopy(self.inputs[0])]