A gcc plugin, which can be loaded when debugging gcc, to show internal structures graphically. Available commands include,

• view-bb ---- show the basic block
• view-bbs ---- show the basic blocks
• view-cgraph ---- show the current call graph
• view-dominance ---- show the current dominance graph
• view-function ---- show the current function in tree-level
• view-gimple-hierarchy ---- show gimple statement structure hierarchy
• view-loop ---- show the loop
• view-passes ---- show passes
• view-rtx ---- show a specified rtx
• view-tree ---- show a specified tree
• view-tree-hierarchy ---- show tree structure hierarchy
• view-tree-hierarchy-4-6 ---- show tree structure hierarchy for gcc 4.6
• view-tree-hierarchy-4-7 ---- show tree structure hierarchy for gcc 4.7

Here's an example about how to use vcg-plugin in gdb (with vcg-plugin.gdbinit):

gdb -q -args /path/to/cc1 test.c -fplugin=/path/to/vcg_plugin.so -O2

gdb) b ...

gdb) r

gdb) view-passes

you can use -fplugin-arg-vcg_plugin-viewer=vcgview to select vcg viewer, default is vcgview (http://code.google.com/p/vcgviewer).

The plugin also can work without gdb, using -fplugin-arg-vcg_plugin-option. Options are,

• cgraph ---- dump the call graph before IPA passes.
• cgraph-callee ---- dump the callee graph for each function.
• cgraph-caller ---- dump the caller graph for each function.
• gimple-hierarchy ---- dump the gimple hierarchy graph.
• help ---- show this help.
• passes ---- dump the passes graph.
• pass-lists ---- dump the pass lists graph.
• tree-hierarchy ---- dump the tree hierarchy graph.
• tree-hierarchy-4-6 ---- dump the tree hierarchy graph for gcc 4.6.
• tree-hierarchy-4-7 ---- dump the tree hierarchy graph for gcc 4.7.
• viewer=name ---- set the vcg viewer, default is vcgview.

Here's an example about how to use vcg-plugin without gdb:

gcc -fplugin=/path/to/vcg_plugin.so -fplugin-arg-vcg_plugin-cgraph foo.c

Supported GCC:

• gcc 4.6 or 4.7 (trunk).
• gcc 4.5 is not guaranteed, because I don't test on it.

TODO:

• view ...

Any suggestions are welcome. Send email to <mingjie.xing AT gmail.com>.