Loop colorizer

Sometimes I need to know if the current instruction sequence belongs to a loop or not.
If it does, I’d like to know the loop boundaries. It would be nice to have the current
loop highlighted. If the highlight changes as I navigate in the listing, it would be just

This is why I created this colorizer plugin. Implementing it turned out to be
easier than I thought 🙂 Pretty simple stuff but still useful.

There are no controls, no setup, nothing: the plugin is fully automatic.
The listing looks like this with it:

I used only cross-references to detect loops. This allows the plugin to work with
any processor. It detects the outermost loop (however I have a feeling that
the innermost loop would be better)…

As usual, the source code is available. In fact you have a chance of learning
how to write this plugin and similar modules for IDA.
We will be learning this and other things in detail during the

advanced training held in Columbia, MD, Nov 1-2
If you are interested,
send us a message!

Feel free to play with the plugin and improve it!

Download it here:

13 thoughts on “Loop colorizer”

  1. seems to give an access violation when I placed this plugin in IDA50 plugins and loaded a database

  2. seems to give an access violation when I placed this plugin in IDA50 plugins and loaded a database

  3. Same here with IDA 5.0:
    Access violation at address 100E8403 in module ‘ida.wll’. Read of address 9010ADEC.
    This seems to happen when I switch to text-view and scroll.
    I tried with different databases.
    Looks like a problem when color_loops.plw calls ida_create_flow_chart.
    Call stack:
    100E8403 ida.wll
    1006CE44 ida.wll
    1006BA55 ida.wll (ida_create_flow_chart)
    04AF2E8F color_loops.plw
    04AF2212 color_loops.plw
    04AF18F3 color_loops.plw
    04AF1A30 color_loops.plw
    10036EF4 ida.wll (ida_invoke_callbacks)
    0045FA56 .text
    10028159 ida.wll
    400F6231 vcl60.bpl
    400F5873 vcl60.bpl
    0040226E .text
    00567870 .text
    I don’t know enough yet about IDA plugins to determine the root cause.

  4. Like a charm 🙂
    What was the problem?
    I tried tracing IDA in IDA and comparing with the plugin source, but I guess I still lack experience..

  5. The problem was due to separate memory pools in the ida kernel and plugin dll. I redirected memory allocation functions to the kernel.

  6. hm, when IDA starts i get:
    LoadLibrary(c:\programme\ida\plugins\loopcolorizer.plw) => error code 126
    c:\programme\ida\plugins\loopcolorizer.plw: can’t load file
    plugins.cfg has config:
    color_loops.plw loopcolorizer Ctrl-F12 3
    even if i compile it myself.
    ida version used is: 5.0

  7. Wait a minute, your plugin is named color_loop.plw or loopcolorizer.plw?
    To solve the problem, remove your line from plugins.cfg

  8. Ditto, crashes for me too.
    And just having the file in the “..\plugins” directory (sans line in “plugins.cfg”) causes the crash!

  9. Well, try to debug the plugin and find why it crashes. It comes with the source code.

  10. Grad the source code, change the color and recompile it. The color is hardcoded.

Comments are closed.