fill in more hwif utility functions for dereferencer

peakrdl/regblock/utils.py

@@ -0,0 +1,30 @@
+import re
+from typing import TYPE_CHECKING
+import textwrap
+
+if TYPE_CHECKING:
+    from systemrdl.node import Node
+    from .signals import SignalBase
+
+def get_indexed_path(top_node: 'Node', target_node: 'Node') -> str:
+    """
+    TODO: Add words about indexing and why i'm doing this. Copy from logbook
+    """
+    path = target_node.get_rel_path(top_node, empty_array_suffix="[!]")
+    # replace unknown indexes with incrementing iterators i0, i1, ...
+    class repl:
+        def __init__(self):
+            self.i = 0
+        def __call__(self, match):
+            s = f'i{self.i}'
+            self.i += 1
+            return s
+    return re.sub(r'!', repl(), path)
+
+
+def get_always_ff_event(resetsignal: 'SignalBase') -> str:
+    if resetsignal.is_async and resetsignal.is_activehigh:
+        return f"@(posedge clk or posedge {resetsignal.identifier})"
+    elif resetsignal.is_async and not resetsignal.is_activehigh:
+        return f"@(posedge clk or negedge {resetsignal.identifier})"
+    return "@(posedge clk)"