1 files changed, 53 insertions, 0 deletions
diff --git a/circuitpython/tools/diff_nm_sizes.py b/circuitpython/tools/diff_nm_sizes.py
new file mode 100644
index 0000000..241355e
--- /dev/null
+++ b/circuitpython/tools/diff_nm_sizes.py
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+"""This script diffs two dumps of symbol sizes by matching up the symbol names
+
+To generate the input files do something like:
+
+arm-none-eabi-nm --size-sort build-bluemicro833/firmware.elf > new_sizes.txt
+
+The command will vary by board and along with git state.
+
+To print the diff do:
+
+python diff_nm_sizes.py old_sizes.txt new_sizes.txt
+"""
+
+import sys
+import pathlib
+
+old = pathlib.Path(sys.argv[-2])
+new = pathlib.Path(sys.argv[-1])
+old_symbols = {}
+old_total_size = 0
+longest_symbol = 0
+for line in old.read_text().split("\n"):
+    if not line:
+        continue
+    size, t, name = line.split()
+    old_size = int(size, 16)
+    old_total_size += old_size
+    old_symbols[name] = old_size
+    longest_symbol = max(longest_symbol, len(name))
+
+new_total_size = 0
+for line in new.read_text().split("\n"):
+    if not line:
+        continue
+    size, t, name = line.split()
+    size = int(size, 16)
+    new_total_size += size
+    if name not in old_symbols:
+        print(f"{name:<{longest_symbol}}{size:>+6}")
+    else:
+        old_size = old_symbols[name]
+        del old_symbols[name]
+        if size == old_size:
+            continue
+        print(f"{name:<{longest_symbol}}{size - old_size:>+6}")
+
+for name in old_symbols:
+    old_size = old_symbols[name]
+    print(f"{name:<{longest_symbol}}{-old_size:>+6}")
+
+print()
+total_label = f"Total {new_total_size} - {old_total_size}"
+print(f"{total_label:<{longest_symbol}}{new_total_size - old_total_size:>+6}")