Add new directory under utils for code-analysis tools, and objdiff.py script to display per-symbol size deltas between object files.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@20672 a1c6a512-1295-4272-9138-f99709370657

utils/analysis/objdiff.py

@@ -0,0 +1,54 @@
+#!/usr/bin/python
+import sys
+from subprocess import Popen, PIPE
+
+if len(sys.argv) != 3:
+    print """%s usage:
+    %s obj1 obj2
+    Calculate per-symbol and total size differences between obj1 and obj2,
+    which may be any files that nm can read""" % ((sys.argv[0],)*2)
+    sys.exit(2)
+
+obj1 = sys.argv[1]
+obj2 = sys.argv[2]
+
+def getsyms(obj):
+    proc = Popen(args=['nm', '-S', '-t', 'd', obj], stdout=PIPE, stderr=PIPE)
+    out, err = proc.communicate()
+    if err:
+        print "nm reported an error:\n"
+        print err
+        sys.exit(1)
+    d = {}
+    for l in out.splitlines():
+        l = l.strip().split()
+        if len(l) == 4:
+            d[l[3]] = int(l[1])
+    return d
+
+diff = 0
+
+d1 = getsyms(obj1)
+d2 = getsyms(obj2)
+l = [(k,v) for k,v in sorted(d1.items()) if k not in d2]
+if l:
+    print "only in %s" % obj1
+    print ''.join("  %6d %s\n" % (v,k) for k,v in l)
+    diff -= sum(v for k,v in l)
+
+l = [(k,v) for k,v in sorted(d2.items()) if k not in d1]
+if l:
+    print "only in %s" % obj2
+    print ''.join("%6d %s\n" % (v,k) for k,v in l)
+    diff += sum(v for k,v in l)
+
+l = [(k,v,d2[k]) for k,v in sorted(d1.items()) if k in d2 and d2[k] != v]
+if l:
+    print "different sizes in %s and %s:" %(obj1, obj2)
+    print ''.join("  %6d %6d %s\n" % (v1,v2,k) for k,v1,v2 in l)
+    diff += sum(v2-v1 for k,v1,v2 in l)
+
+if diff:
+    print "total size difference: %+d" % diff
+else:
+    print "total size difference:  0"