1 files changed, 118 insertions, 0 deletions
diff --git a/circuitpython/tools/gc_activity.py b/circuitpython/tools/gc_activity.py
new file mode 100644
index 0000000..6a1772f
--- /dev/null
+++ b/circuitpython/tools/gc_activity.py
@@ -0,0 +1,118 @@
+# SPDX-FileCopyrightText: 2014 MicroPython & CircuitPython contributors (https://github.com/adafruit/circuitpython/graphs/contributors)
+#
+# SPDX-License-Identifier: MIT
+
+import sys
+import json
+
+# Map start block to current allocation info.
+current_heap = {}
+allocation_history = []
+root = {}
+
+
+def change_root(trace, size):
+    level = root
+    for frame in reversed(trace):
+        file_location = frame[1]
+        if file_location not in level:
+            level[file_location] = {
+                "blocks": 0,
+                "file": file_location,
+                "function": frame[2],
+                "subcalls": {},
+            }
+        level[file_location]["blocks"] += size
+        level = level[file_location]["subcalls"]
+
+
+total_actions = 0
+with open(sys.argv[1], "r") as f:
+    for line in f:
+        if not line.strip():
+            break
+    for line in f:
+        action = None
+        if line.startswith("Breakpoint 2"):
+            break
+        next(f)  # throw away breakpoint code line
+        next(f)  # first frame
+        block = 0
+        size = 0
+        trace = []
+        for line in f:
+            # print(line.strip())
+            if line[0] == "#":
+                frame = line.strip().split()
+                if frame[1].startswith("0x"):
+                    trace.append((frame[1], frame[-1], frame[3]))
+                else:
+                    trace.append(("0x0", frame[-1], frame[1]))
+            elif line[0] == "$":
+                block = int(line.strip().split()[-1][2:], 16)
+                size = int(next(f).strip().split()[-1][2:], 16)
+            if not line.strip():
+                break
+
+        action = "unknown"
+        if block not in current_heap:
+            current_heap[block] = {
+                "start_block": block,
+                "size": size,
+                "start_trace": trace,
+                "start_time": total_actions,
+            }
+            action = "alloc"
+            change_root(trace, size)
+        else:
+            alloc = current_heap[block]
+            alloc["end_trace"] = trace
+            alloc["end_time"] = total_actions
+            change_root(alloc["start_trace"], -1 * alloc["size"])
+            if size > 0:
+                action = "realloc"
+                current_heap[block] = {
+                    "start_block": block,
+                    "size": size,
+                    "start_trace": trace,
+                    "start_time": total_actions,
+                }
+                change_root(trace, size)
+            else:
+                action = "free"
+                if trace[0][2] == "gc_sweep":
+                    action = "sweep"
+                del current_heap[block]
+            alloc["end_cause"] = action
+            allocation_history.append(alloc)
+        print(total_actions, action, block, size)
+        total_actions += 1
+
+print()
+
+for alloc in current_heap.values():
+    alloc["end_trace"] = ""
+    alloc["end_time"] = total_actions
+    allocation_history.append(alloc)
+
+
+def print_frame(frame, indent=0):
+    for key in sorted(frame):
+        if (
+            not frame[key]["blocks"]
+            or key.startswith("../py/malloc.c")
+            or key.startswith("../py/gc.c")
+        ):
+            continue
+        print(" " * (indent - 1), key, frame[key]["function"], frame[key]["blocks"], "blocks")
+        print_frame(frame[key]["subcalls"], indent + 2)
+
+
+print_frame(root)
+total_blocks = 0
+for key in sorted(root):
+    total_blocks += root[key]["blocks"]
+print(total_blocks, "total blocks")
+
+with open("allocation_history.json", "w") as f:
+    json.dump(allocation_history, f)