fill in more hwif utility functions for dereferencer

peakrdl/regblock/forloop_generator.py

@@ -0,0 +1,96 @@
+from typing import TYPE_CHECKING, Optional, List
+import textwrap
+
+from systemrdl.walker import RDLListener, RDLWalker
+
+if TYPE_CHECKING:
+    from systemrdl.node import AddressableNode, Node
+
+class Body:
+
+    def __init__(self) -> None:
+        self.children = []
+
+    def __str__(self) -> str:
+        s = '\n'.join((str(x) for x in self.children))
+        return s
+
+class LoopBody(Body):
+    def __init__(self, dim: int, iterator: str, i_type: str) -> None:
+        super().__init__()
+        self.dim = dim
+        self.iterator = iterator
+        self.i_type = i_type
+
+    def __str__(self) -> str:
+        s = super().__str__()
+        return (
+            f"for({self.i_type} {self.iterator}=0; {self.iterator}<{self.dim}; {self.iterator}++) begin\n"
+            + textwrap.indent(s, "    ")
+            + "\nend"
+        )
+
+
+
+class ForLoopGenerator:
+    i_type = "int"
+
+    def __init__(self) -> None:
+        self._loop_level = 0
+        self._stack = []
+
+    @property
+    def current_loop(self) -> Body:
+        return self._stack[-1]
+
+    def push_loop(self, dim: int) -> None:
+        i = f"i{self._loop_level}"
+        b = LoopBody(dim, i, self.i_type)
+        self._stack.append(b)
+        self._loop_level += 1
+
+    def add_content(self, s: str) -> None:
+        self.current_loop.children.append(s)
+
+    def pop_loop(self) -> None:
+        b = self._stack.pop()
+
+        if b.children:
+            # Loop body is not empty. Attach it to the parent
+            self.current_loop.children.append(b)
+        self._loop_level -= 1
+
+    def start(self):
+        assert not self._stack
+        b = Body()
+        self._stack.append(b)
+
+    def finish(self) -> Optional[str]:
+        b = self._stack.pop()
+        assert not self._stack
+
+        if not b.children:
+            return None
+        return str(b)
+
+class RDLForLoopGenerator(ForLoopGenerator, RDLListener):
+
+    def get_content(self, node: 'Node') -> Optional[str]:
+        self.start()
+        walker = RDLWalker()
+        walker.walk(node, self, skip_top=True)
+        return self.finish()
+
+    def enter_AddressableComponent(self, node: 'AddressableNode') -> None:
+        if not node.is_array:
+            return
+
+        for dim in node.array_dimensions:
+            self.push_loop(dim)
+
+    def exit_AddressableComponent(self, node: 'AddressableNode') -> None:
+        if not node.is_array:
+            return
+
+        for _ in node.array_dimensions:
+            self.pop_loop()