Index: gcc/flags.h
===================================================================
--- gcc/flags.h	(revision 114563)
+++ gcc/flags.h	(working copy)
@@ -194,6 +194,10 @@ extern int profile_flag;
 
 extern int profile_arc_flag;
 
+/* Nonzero if generating code graph  */
+
+extern int flag_code_graph_generation;
+
 /* Nonzero if value profile should be measured.  */
 
 extern int flag_profile_values;
Index: gcc/cgraph.c
===================================================================
--- gcc/cgraph.c	(revision 114563)
+++ gcc/cgraph.c	(working copy)
@@ -68,7 +68,8 @@ int cgraph_varpool_n_nodes;
 static GTY(())  struct cgraph_varpool_node *cgraph_varpool_nodes;
 
 static struct cgraph_edge *create_edge (struct cgraph_node *,
-					struct cgraph_node *);
+					struct cgraph_node *,
+					location_t call_location);
 static hashval_t hash_node (const void *);
 static int eq_node (const void *, const void *);
 
@@ -152,7 +153,7 @@ cgraph_node_for_identifier (tree id)
 /* Create edge from CALLER to CALLEE in the cgraph.  */
 
 static struct cgraph_edge *
-create_edge (struct cgraph_node *caller, struct cgraph_node *callee)
+create_edge (struct cgraph_node *caller, struct cgraph_node *callee, location_t call_location)
 {
   struct cgraph_edge *edge = ggc_alloc (sizeof (struct cgraph_edge));
   struct cgraph_edge *edge2;
@@ -180,6 +181,7 @@ create_edge (struct cgraph_node *caller,
 
   edge->caller = caller;
   edge->callee = callee;
+  edge->call_location = call_location;
   edge->next_caller = callee->callers;
   edge->next_callee = caller->callees;
   caller->callees = edge;
@@ -295,7 +297,7 @@ cgraph_mark_needed_node (struct cgraph_n
 struct cgraph_edge *
 cgraph_record_call (tree caller, tree callee)
 {
-  return create_edge (cgraph_node (caller), cgraph_node (callee));
+  return create_edge (cgraph_node (caller), cgraph_node (callee), input_location);
 }
 
 void
Index: gcc/cgraph.h
===================================================================
--- gcc/cgraph.h	(revision 114563)
+++ gcc/cgraph.h	(working copy)
@@ -126,6 +126,9 @@ struct cgraph_edge GTY(())
   /* When NULL, inline this call.  When non-NULL, points to the explanation
      why function was not inlined.  */
   const char *inline_failed;
+
+  /* CodeViz: Location the call occurred at */
+  location_t call_location;
 };
 
 /* The cgraph_varpool data structure.
Index: gcc/tree.h
===================================================================
--- gcc/tree.h	(revision 114563)
+++ gcc/tree.h	(working copy)
@@ -3115,4 +3115,11 @@ typedef enum
 extern int tree_node_counts[];
 extern int tree_node_sizes[];
     
+/*
+ * CodeViz functions to get the output file handle for cdepn files
+ */
+FILE *cdepn_open(char *filename);
+void cdepn_close(void);
+int  cdepn_checkprint(void *fncheck);
+
 #endif  /* GCC_TREE_H  */
Index: gcc/common.opt
===================================================================
--- gcc/common.opt	(revision 114563)
+++ gcc/common.opt	(working copy)
@@ -456,6 +456,10 @@ fnon-call-exceptions
 Common
 Support synchronous non-call exceptions
 
+fcode-graph-generation
+Common
+Enable code graph generation
+
 fold-unroll-loops
 Common
 Perform loop unrolling when iteration count is known
Index: gcc/toplev.c
===================================================================
--- gcc/toplev.c	(revision 114563)
+++ gcc/toplev.c	(working copy)
@@ -950,6 +950,10 @@ int flag_renumber_insns = 1;
 /* If nonzero, use the graph coloring register allocator.  */
 int flag_new_regalloc = 0;
 
+/* Nonzero if generating call graph.  */
+
+int flag_code_graph_generation = 0;
+
 /* Nonzero if we perform superblock formation.  */
 
 int flag_tracer = 0;
@@ -1149,6 +1153,7 @@ static const lang_independent_options f_
   {"unsafe-math-optimizations", &flag_unsafe_math_optimizations, 1 },
   {"signaling-nans", &flag_signaling_nans, 1 },
   {"bounds-check", &flag_bounds_check, 1 },
+  {"code-graph-generation", &flag_code_graph_generation, 1 },
   {"single-precision-constant", &flag_single_precision_constant, 1 },
   {"time-report", &time_report, 1 },
   {"mem-report", &mem_report, 1 },
@@ -4675,6 +4680,58 @@ do_compile (void)
   timevar_print (stderr);
 }
 
+/*
+ * codeviz: Open the cdepn file. This is called with a filename by main()
+ * and with just NULL for every other instance to return just the handle
+ */
+FILE *g_fnref_f = NULL;
+char cdepnfile[256] = "--wonthappen--";
+
+FILE *cdepn_open(char *filename)
+{
+  struct stat cdepnstat;
+  int errval;
+  time_t currtime;
+  if (filename && g_fnref_f == NULL) {
+    strcpy(cdepnfile, filename);
+    strcat(cdepnfile, ".cdepn");
+
+    /*
+     * Decide whether to open write or append. There appears to be a weird
+     * bug that decides to open the file twice, overwriting all the cdepn
+     * information put there before
+     */
+    errval = stat(cdepnfile, &cdepnstat); 
+    currtime = time(NULL);
+    if (errval == -1 || currtime - cdepnstat.st_mtime > 5)  {
+      g_fnref_f = fopen(cdepnfile, "w");
+      fprintf(stderr, "opened dep file %s\n",cdepnfile);
+    } 
+    else {
+      g_fnref_f = fopen(cdepnfile, "a");
+      fprintf(stderr, "append dep file %s\n",cdepnfile);
+    }
+
+    fflush(stderr);
+  }
+
+  return g_fnref_f;
+}
+
+void cdepn_close(void) 
+{
+  if (g_fnref_f) {
+    fclose(g_fnref_f);
+  }
+  g_fnref_f = NULL;
+}
+
+int cdepn_checkprint(void *fncheck) 
+{
+  return 1;
+  /*return (void *)fncheck == (void *)decl_name; */
+}
+
 /* Entry point of cc1, cc1plus, jc1, f771, etc.
    Exit code is FATAL_EXIT_CODE if can't open files or if there were
    any errors, or SUCCESS_EXIT_CODE if compilation succeeded.
@@ -4696,8 +4753,13 @@ toplev_main (unsigned int argc, const ch
   randomize ();
 
   /* Exit early if we can (e.g. -help).  */
-  if (!exit_after_options)
+  if (!exit_after_options) {
+    if (flag_code_graph_generation)
+      cdepn_open(main_input_filename);
     do_compile ();
+    if (flag_code_graph_generation)
+      cdepn_close();
+  }
 
   if (errorcount || sorrycount)
     return (FATAL_EXIT_CODE);
Index: gcc/cgraphunit.c
===================================================================
--- gcc/cgraphunit.c	(revision 114563)
+++ gcc/cgraphunit.c	(working copy)
@@ -320,7 +320,10 @@ static void
 cgraph_analyze_function (struct cgraph_node *node)
 {
   tree decl = node->decl;
+  tree thisTree, calleeTree;
+  FILE *fnref_f;
   struct cgraph_edge *e;
+  struct cgraph_edge *calleeEdge;
 
   current_function_decl = decl;
 
@@ -358,6 +361,35 @@ cgraph_analyze_function (struct cgraph_n
   node->analyzed = true;
   current_function_decl = NULL;
 
+  if (!flag_code_graph_generation)
+    goto rest_in_cgraph_analyze;
+
+  /* CodeViz: Output information on this node */
+  thisTree = node->decl;
+  if ((fnref_f = cdepn_open(NULL))) 
+    {
+      fprintf(fnref_f,"F {%s} {%s:%d}\n",
+        lang_hooks.decl_printable_name (thisTree, 2),
+        DECL_SOURCE_FILE (thisTree), DECL_SOURCE_LINE (thisTree));
+    }
+
+  /* CodeViz: Output information on all functions this node calls */
+  for (calleeEdge = node->callees; calleeEdge; calleeEdge = calleeEdge->next_callee) 
+    {
+    calleeTree = calleeEdge->callee->decl;
+      if (thisTree != NULL && calleeTree != NULL &&
+          (fnref_f = cdepn_open(NULL)) != NULL) {
+        fprintf(fnref_f, "C {%s} {%s:%d} {%s}\n",
+          lang_hooks.decl_printable_name (thisTree, 2),
+          calleeEdge->call_location.file, calleeEdge->call_location.line,
+          lang_hooks.decl_printable_name (calleeTree, 2));
+      }
+      else {
+        printf("CODEVIZ: Unexpected NULL encountered\n");
+      }
+    }
+
+rest_in_cgraph_analyze:
   /* Possibly warn about unused parameters.  */
   if (warn_unused_parameter)
     do_warn_unused_parameter (decl);
Index: gcc/opts.c
===================================================================
--- gcc/opts.c	(revision 114563)
+++ gcc/opts.c	(working copy)
@@ -1361,6 +1361,10 @@ common_handle_option (size_t scode, cons
       stack_limit_rtx = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (arg));
       break;
 
+    case OPT_fcode_graph_generation:
+      flag_code_graph_generation = value;
+      break;
+
     case OPT_fstrength_reduce:
       flag_strength_reduce = value;
       break;