[gimp] tools: add performance-log-related tools

[Ell <ell src gnome org>]

commit d7c74a615b0760e87727f38e564748aab3904af7
Author: Ell <ell_se yahoo com>
Date:   Sun Sep 2 02:28:44 2018 -0400

    tools: add performance-log-related tools
    
    performance-log-expand.py decodes a delta-encoded performance log
    by expanding the deltas, producing a log where each sample (and
    other relevant elements) contain complete information.  Note that
    the structure of expanded logs is identical to that of delta-
    encoded logs, the expanded log simply has no deltas.
    
    performance-log-resolve.py resolves symbol information in
    backtraces.  The logs produced by GIMP only specify the program
    counter at each stack frame, providing an address-map to map
    program-counter addresses to actual symbols separately.  This tool
    looks up each program-counter address in the address map,
    incorporating the relevant symbol information directly into the
    backtrace.
    
    Both tools read their input from STDIN, and write their output to
    STDOUT, and can be chained in a pipeline (with
    gimp-performance-log-expand.py appearing first).
    
    Note that these tools require Python 3.

 tools/Makefile.am                |   8 +--
 tools/performance-log-expand.py  | 106 +++++++++++++++++++++++++++++++++++++++
 tools/performance-log-resolve.py |  55 ++++++++++++++++++++
 3 files changed, 166 insertions(+), 3 deletions(-)
---
diff --git a/tools/Makefile.am b/tools/Makefile.am
index 2dbcb89fd6..4c5420f4e5 100644
--- a/tools/Makefile.am
+++ b/tools/Makefile.am
@@ -96,6 +96,8 @@ AM_LDFLAGS = \
        $(xnone)
 
 EXTRA_DIST = \
-       defcheck.py     \
-       gimp-mkenums    \
-       gimppath2svg.py
+       defcheck.py                     \
+       gimp-mkenums                    \
+       gimppath2svg.py                 \
+       performance-log-expand.py       \
+       performance-log-resolve.py
diff --git a/tools/performance-log-expand.py b/tools/performance-log-expand.py
new file mode 100755
index 0000000000..c0f7cc9471
--- /dev/null
+++ b/tools/performance-log-expand.py
@@ -0,0 +1,106 @@
+#!/usr/bin/env python3
+
+"""
+performance-log-expand.py -- Delta-decodes GIMP performance logs
+Copyright (C) 2018  Ell
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+
+Usage: performance-log-expand.py < infile > outfile
+"""
+
+from xml.etree import ElementTree
+import sys
+
+empty_element = ElementTree.Element ("")
+
+# Read performance log from STDIN
+log = ElementTree.fromstring (sys.stdin.buffer.read ())
+
+try:
+    has_backtrace = bool (int (log.find ("params").find ("backtrace").text))
+except:
+    has_backtrace = False
+
+def expand_simple (element, last_values):
+    last_values.update ({value.tag: value.text for value in element})
+
+    for value in list (element):
+        element.remove (value)
+
+    for tag, text in last_values.items ():
+        value = ElementTree.SubElement (element, tag)
+        value.text = text
+        value.tail = "\n"
+
+# Expand samples
+last_vars      = {}
+last_backtrace = {}
+
+for sample in (log.find ("samples") or empty_element).iterfind ("sample"):
+    # Expand variables
+    vars = sample.find ("vars") or \
+           ElementTree.SubElement (sample, "vars")
+
+    expand_simple (vars, last_vars)
+
+    # Expand backtrace
+    if has_backtrace:
+        backtrace = sample.find ("backtrace") or \
+                    ElementTree.SubElement (sample, "backtrace")
+
+        for thread in backtrace:
+            id     = thread.get ("id")
+            frames = list (thread)
+
+            if not frames:
+                last_backtrace.pop (id, None)
+            else:
+                last_thread = last_backtrace.setdefault (id, [None, []])
+                last_frames = last_thread[1]
+
+                name = thread.get ("name")
+                head = thread.get ("head")
+                tail = thread.get ("tail")
+
+                if head:
+                    frames = last_frames[:int (head)] + frames
+                if tail:
+                    frames = frames + last_frames[-int (tail):]
+
+                last_thread[0] = name
+                last_thread[1] = frames
+
+        for thread in list (backtrace):
+            backtrace.remove (thread)
+
+        for id, (name, frames) in last_backtrace.items ():
+            thread = ElementTree.SubElement (backtrace, "thread", id=id)
+            thread.text = "\n"
+            thread.tail = "\n"
+
+            if name:
+                thread.set ("name", name)
+
+            thread.extend (frames)
+
+# Expand address map
+last_address = {}
+
+for address in (log.find ("address-map") or empty_element).iterfind ("address"):
+    expand_simple (address, last_address)
+
+# Write performance log to STDOUT
+sys.stdout.buffer.write (ElementTree.tostring (log))
diff --git a/tools/performance-log-resolve.py b/tools/performance-log-resolve.py
new file mode 100755
index 0000000000..272f0ebb24
--- /dev/null
+++ b/tools/performance-log-resolve.py
@@ -0,0 +1,55 @@
+#!/usr/bin/env python3
+
+"""
+performance-log-resolve.py -- Resolve GIMP performance log backtrace symbols
+Copyright (C) 2018  Ell
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+
+Usage: performance-log-resolve.py < infile > outfile
+"""
+
+from xml.etree import ElementTree
+import sys
+
+empty_element = ElementTree.Element ("")
+
+# Read performance log from STDIN
+log = ElementTree.fromstring (sys.stdin.buffer.read ())
+
+address_map = log.find ("address-map")
+
+if address_map:
+    # Create address dictionary
+    addresses = {}
+
+    for address in address_map.iterfind ("address"):
+        addresses[address.get ("value")] = list (address)
+
+    # Resolve addresses in backtraces
+    for sample in (log.find ("samples") or empty_element).iterfind ("sample"):
+        for thread in sample.find ("backtrace") or ():
+            for frame in thread:
+                address = addresses.get (frame.get ("address"))
+
+                if address:
+                    frame.text = "\n"
+                    frame.extend (address)
+
+    # Remove address map
+    log.remove (address_map)
+
+# Write performance log to STDOUT
+sys.stdout.buffer.write (ElementTree.tostring (log))