GCC plugin: dump call graph for a single file.

dump_call_graph.cpp

#include "gcc-plugin.h"
#include "plugin-version.h"

#include "tree.h"
#include "cgraph.h"

#include <string>
#include <vector>
#include <map>

#define DEBUG(...) fprintf(stderr, __VA_ARGS__)

int plugin_is_GPL_compatible;

extern symbol_table *symtab;

/* Define main structure. */
typedef std::string Name;
typedef std::vector<std::string> Callees;

typedef std::map<Name, Callees> CallGraph;

static CallGraph call_graph;

#define FUNCTION_NAME(fun) (const char*) IDENTIFIER_POINTER \
  (DECL_ASSEMBLER_NAME ((fun) ->decl))

/* Plugin callback function for PLUGIN_ALL_IPA_PASSES_START */

void
dump_callgraph (void * ARG_UNUSED (gcc_data),
                void * ARG_UNUSED (data))
{
  for (cgraph_node* node = symtab->first_function ();
       node;
       node = symtab->next_function (node))
    {
      if (!node->callees)
        continue;

      for (cgraph_edge* edge = node->callees;
           edge;
           edge = edge->next_callee)
        {
          std::string sfn (FUNCTION_NAME (edge->caller->get_fun ()));
          std::string dfn (FUNCTION_NAME (edge->callee->get_fun ()));

          call_graph[sfn].push_back (dfn);
        }
    }

  for (CallGraph::iterator iter = call_graph.begin ();
       iter != call_graph.end ();
       ++iter)
    {
        DEBUG ("%s\n", iter->first.c_str ());
        for (Callees::iterator citer = iter->second.begin ();
             citer != iter->second.end ();
             ++citer)
          {
            DEBUG ("\t-> %s\n", citer->c_str ());
          }
    }
}


int
plugin_init (struct plugin_name_args *plugin_info,
             struct plugin_gcc_version *version)
{
  /* Check the building plugin compiler and the executing compiler are the
     same.  */
  if (!plugin_default_version_check (version, &gcc_version))
    return 1;


  /* Dump the callgraph before IPA passes.  */
  register_callback (plugin_info -> base_name,
                     PLUGIN_ALL_IPA_PASSES_START,
                     dump_callgraph,
                     NULL);

  return 0;
}