[15] RFR(S): 8247421: [TESTBUG] ReturnBlobToWrongHeapTest.java failed allocating blob

[Nils Eliasson]

Hi,

This tries to fill up one segment of the code cache with large blobs, 
and then fill up the rest with small code blobs. In one test run the 
large code blob happened to fill up the code heap precisely, leaving no 
room for any small code blob. That made the test fail.

"CodeHeap 'non-profiled nmethods': size=11248Kb used=11248Kb 
max_used=11248Kb free=0Kb
  bounds [0x0000000116701000, 0x00000001171fd000, 0x00000001171fd000]"

My fix allocates one small blob first, then continues on with the large 
blobs, and finally filling up the rest with small blobs. In that way 
there are always a small blob allocated.

Bug: https://bugs.openjdk.java.net/browse/JDK-8247421
Webrev: http://cr.openjdk.java.net/~neliasso/8247421/webrev.01/

Please review,
Nils Eliasson