How to use Dragon to get dynamic information about call graph and control
flow graph. Note the dynamic information is only available for IA-64.

1. use opencc/openf90 to compile your program with feedback option
 uhcc -fb_create myfeedback -fb_type=1 -fb_phase=0 test.c

2. run program using some input
 ./a.out

3. dump call graph/control flow graph using -dragon option
  uhcc -fb_opt myfeedback -dragon -ipa -O2 test.c

4. invoke dragon to show graph
  dragon

To get static information

Generating call graph and control flow graph
1. uhcc -dragon -ipa -O2 test.c

Generating dependence information
2. uhcc -dragon -O3 test.c