simple ptrace-based program execution tracer

    $ tracer -h
    Usage: tracer [program] [args...]
    Run PROGRAM on ARGS printing the values of the program counter.

Trace the executed memory addresses in order.

    $ tracer ./hello|head
    4195344
    4195346
    4195349
    4195350
    4195353
    4195357
    4195358
    4195359
    4195366
    4195373

Disassemble the executable and collect trace data by instruction.
Format used is "address #evaluations disassembly...".

    $ tracer-w-disasm ./hello|grep -C 4 " 10"
    400504  1    movl    $0x0,-0x4(%rbp)
    40050b  1    movl    $0x0,-0x8(%rbp)
    400512  1    movl    $0x0,-0x4(%rbp)
    400519  1    jmp     0000000000400525
    40051b  100  mov     -0x4(%rbp),%eax
    40051e  100  mov     %eax,-0x8(%rbp)
    400521  100  addl    $0x1,-0x4(%rbp)
    400525  101  cmpl    $0x63,-0x4(%rbp)
    400529  101  jle     000000000040051b
    40052b  1    mov     $0x4005e4,%edi
    400530  1    callq   00000000004003e0
    400535  1    leaveq
    400536  1    retq