didn't we use to have a cache for integer boxes?

gistfile1.txt

Stats:
    9 spesh slots
    14 log slots
Logged values:
      0    _     _     _     _     _     _     _     _  
      1    1     1     1     1     1     1     1     1  
      2    2     2     2     2     2     2     2     2  
      3    3     4     5     6     7     8     9    10  
      4    2     2     2     2     2     _     2     2  
      5   11    12    13    14    15     _    16    17  
      6    _     _     _     _     _    18     _     _  
      7    _     _     _     _     _     _     _     _  
      8    _     _     _     _     _     _     _     _  
      9    _     _     _     _     _     _     _     _  
     10   18    18    18    18    18     _    18    18  
     11   19    19    19    19    19     _    19    19  
     12   19    19    19    19    19     _    19    19  
     13    _     _     _     _     _     _     _     _  

    1: 0xacb640 P6int(2)
    2: 0x7f2478c8a778 MVMCode
    3: 0x7f2478ec2d28 P6int(0)
    4: 0x7f2478ec2d88 P6int(0)
    5: 0x7f2478ec2de8 P6int(0)
    6: 0x7f2478ec2e48 P6int(0)
    7: 0x7f2478ec2ea8 P6int(0)
    8: 0x7f2478ec2f08 P6int(1)
    9: 0x7f2478ec2f48 P6int(0)
    10: 0x7f2478ec2fa8 P6int(0)
    11: 0x7f2478ec2d48 P6int(0)
    12: 0x7f2478ec2da8 P6int(0)
    13: 0x7f2478ec2e08 P6int(0)
    14: 0x7f2478ec2e68 P6int(0)
    15: 0x7f2478ec2ec8 P6int(0)
    16: 0x7f2478ec2f68 P6int(0)
    17: 0x7f2478ec2fc8 P6int(0)
    18: 0x7f2478ebd178 Lexotic
    19: 0x7f2478c8aa00 P6int(1073741824)