GraphBuilder::try_inline_full
if it succeeds, it just prints out.
    // printing
    print_inlining(callee);

It ends up with many inline traces without a reason. eg.
                                    @ 1 java.lang.Object::<init> (1 bytes)
               ! @ 390 sun.font.FontLineMetrics::clone (15 bytes)
                              @ 280 java.lang.StringBuilder::<init> (7 bytes)
                                @ 3 java.lang.AbstractStringBuilder::<init> (12 bytes)
                              @ 285 java.lang.StringBuilder::append (8 bytes)
I would like to add a message like "decided by C1"