tools: add script to track size at each merge

tools/get_text_sizes_merges.py

@@ -0,0 +1,68 @@
+#!/usr/bin/env python3
+
+
+MERGES_GIT_CMD = "log --merges --oneline HEAD~{}..HEAD"
+
+OUTFILE = "sizes.data"
+
+from sh import make
+from sh import git
+
+
+with open(OUTFILE, "w") as f:
+    f.write("commit_hash	pr_number	text_size	data_size	bss_size\n")
+
+
+commits = git(MERGES_GIT_CMD.format(50).split(), _tty_out=False)
+
+
+print(commits)
+
+
+for commit in commits:
+    # Each commit looks like:
+    #   33e464c7d Merge #2821
+    #   5cd230d09 Merge pull request #2869 from saki-osive/master
+    fields = commit.split()
+    # Commit hash comes first
+    commit_hash = fields[0]
+    # Extract PR number
+    pr_number = ""
+    for field in fields[1:]:
+        if field[0] == "#":
+            pr_number = field
+
+    # Checkout commit
+    git.checkout(commit_hash)
+
+    print("on hash  {}".format(commit_hash))
+
+    make_output = make()
+
+    text_size = 0
+    data_size = 0
+    bss_size = 0
+    next_line_is_sizes = False
+    for make_output_line in make_output:
+        fields = make_output_line.split()
+        if next_line_is_sizes == True:
+            # Last line we found "text", so the first item on this line is the
+            # size of the text section.
+            text_size = int(fields[0])
+            data_size = int(fields[1])
+            bss_size = int(fields[2])
+            break
+        if fields[0] == "text":
+            next_line_is_sizes = True
+
+    display = "{}\t{}\t{}\t{}\t{}".format(
+        commit_hash, pr_number, text_size, data_size, bss_size
+    )
+    print(display)
+
+    with open(OUTFILE, "a") as f:
+        f.write(display)
+        f.write("\n")
+
+# Go back to master, I guess
+git.checkout("master")