RFR: 8159237: PreservedMarks verification code fails

[Stefan Karlsson]

Hi all,

Please review this patch to fix a recently introduced bug in the 
verification code of the preserved marks code:

http://cr.openjdk.java.net/~stefank/8159237/webrev.01/
https://bugs.openjdk.java.net/browse/JDK-8159237

The bug was introduced when the following code:

volatile size_t total_size = 0; ... for (uint i = 0; i < _num; i += 1) {
total_size += get(i)->size();
get(i)->restore();
}

was moved into a separate function and the address to total_size was 
passed as an argument to the new function. The new function incorrectly 
updates the pointer and not the variable that the pointer points to:

total_size_addr += preserved_marks_set->get(i)->size();

The suggested fix for the bug is:

- total_size_addr += preserved_marks_set->get(i)->size();
+ *total_size_addr += preserved_marks_set->get(i)->size();


Thanks,
StefanK