[PATCH] bloat-o-meter: teach it to handle aliases

[Bernhard Reutner-Fischer]

On Sat, Jan 30, 2010 at 06:09:57PM +0100, Bernhard Reutner-Fischer wrote:
>Previously aliases were counted as full implementation taking up space:
>setservent                                            64      55      -9
>__GI_setservent                                       64      55      -9
>getservent_r                                         420     319    -101
>__GI_getservent_r                                    420     319    -101
>
>Teach it to properly handle aliases.

ping.
Opinions?
>
>Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop at gmail.com>
>---
> scripts/bloat-o-meter |   72 +++++++++++++++++++++++++++++++-----------------
> 1 files changed, 46 insertions(+), 26 deletions(-)
>
>diff --git a/scripts/bloat-o-meter b/scripts/bloat-o-meter
>index eb6fb87..aa12696 100755
>--- a/scripts/bloat-o-meter
>+++ b/scripts/bloat-o-meter
>@@ -21,51 +21,68 @@ for f in sys.argv[1:3]:
>         sys.stderr.write("Error: file '%s' does not exist\n" % f)
>         usage()
> 
>-nm_args = " ".join(sys.argv[3:])
>+sym_args = " ".join(sys.argv[3:])
> def getsizes(file):
>-    sym = {}
>-    for l in os.popen("nm --size-sort %s %s" % (nm_args, file)).readlines():
>-        l = l.strip()
>-        # Skip empty lines
>-        if not len(l): continue
>-        # Skip archive members
>-        if len(l.split()) == 1 and l.endswith(':'):
>-          continue
>-        size, type, name = l.split()
>-        if type in "tTdDbBrR":
>-            if "." in name: name = "static." + name.split(".")[0]
>-            sym[name] = sym.get(name, 0) + int(size, 16)
>-    for l in os.popen("readelf -S " + file).readlines():
>+    sym, alias = {}, {}
>+    dynsym_filter = re.compile("^\s+\d+:\s+[\dA-Fa-f]+\s+\d+\s+\w+\s+\w+\s+\w+\s+\w+\s+\w+\n$")
>+    for l in os.popen("readelf -W -s %s %s" % (sym_args, file)).readlines():
>+        if not dynsym_filter.match(l): continue
>+        num, value, size, typ, bind, vis, ndx, name = l.strip().split()
>+        if ndx == "UND": continue # skip undefined
>+        if typ in ["SECTION", "FILES"]: continue # skip sections and files
>+        if "." in name: name = "static." + name.split(".")[0]
>+        value = int(value, 16)
>+        size = int(size)
>+        if bind != "GLOBAL": # see if it is an alias
>+            alias[name] = {"addr" : value, "size":  size}
>+        else:
>+            sym[name] = {"addr" : value, "size":  size}
>+    for a_nam, a_dat in alias.iteritems():
>+        impl = [k for k, v in sym.iteritems() if v.get("addr") == a_dat["addr"]]
>+        # If the non-GLOBAL sym has an implementation elsewhere then
>+        # it's an alias, disregard it.
>+        if not impl:
>+            # If this non-GLOBAL sym does not have an implementation at
>+            # another address, then treat it as a normal symbol.
>+            sym[a_nam] = a_dat
>+    for l in os.popen("readelf -W -S " + file).readlines():
>         x = l.split()
>-        if len(x)<6 or x[1] != ".rodata": continue
>-        sym[".rodata"] = int(x[5], 16)
>+        if len(x)<6: continue
>+        # Should take these into account too!
>+        #if x[1] not in [".text", ".rodata", ".symtab", ".strtab"]: continue
>+        if x[1] not in [".rodata"]: continue
>+        sym[x[1]] = {"addr" : int(x[3], 16), "size" : int(x[5], 16)}
>     return sym
> 
> old = getsizes(sys.argv[1])
> new = getsizes(sys.argv[2])
> grow, shrink, add, remove, up, down = 0, 0, 0, 0, 0, 0
>-delta, common = [], {}
>+delta, common = [], []
> 
>-for a in old:
>+for a in old.iterkeys():
>     if a in new:
>-        common[a] = 1
>+        common.append(a)
> 
> for name in old:
>     if name not in common:
>         remove += 1
>-        down += old[name]
>-        delta.append((-old[name], name))
>+        sz = old[name].get("size", 0)
>+        down += sz
>+        delta.append((-sz, name))
> 
> for name in new:
>     if name not in common:
>         add += 1
>-        up += new[name]
>-        delta.append((new[name], name))
>+        sz = new[name].get("size", 0)
>+        up += sz
>+        delta.append((sz, name))
> 
> for name in common:
>-        d = new.get(name, 0) - old.get(name, 0)
>+        d = new[name].get("size", 0) - old[name].get("size", 0)
>         if d>0: grow, up = grow+1, up+d
>-        if d<0: shrink, down = shrink+1, down-d
>+        elif d<0: shrink, down = shrink+1, down-d
>+        else:
>+            continue
>         delta.append((d, name))
> 
> delta.sort()
>@@ -73,7 +90,10 @@ delta.reverse()
> 
> print "%-48s %7s %7s %+7s" % ("function", "old", "new", "delta")
> for d, n in delta:
>-    if d: print "%-48s %7s %7s %+7d" % (n, old.get(n,"-"), new.get(n,"-"), d)
>+    if d:
>+        old_sz = old.get(n, {}).get("size", "-")
>+        new_sz = new.get(n, {}).get("size", "-")
>+        print "%-48s %7s %7s %+7d" % (n, old_sz, new_sz, d)
> print "-"*78
> total="(add/remove: %s/%s grow/shrink: %s/%s up/down: %s/%s)%%sTotal: %s bytes"\
>     % (add, remove, grow, shrink, up, -down, up-down)
>-- 
>1.6.5
>