Summary:
Adds iteration of all application memory in an efficient manner using
shadow faults. Shadow memory starts out inaccessible and we mark it
writable one page at a time on each fault when the instrumentation touches
it. This allows iteration over just the mapped shadow memory, saving
significant time.
Adds a process-end iteration and pretty-printing of the final result.
Adds a new test and updates the existing tests.
Reviewers: aizatsky, filcab
Subscribers: vitalybuka, zhaoqin, kcc, eugenis, llvm-commits, kubabrecka
Differential Revision: http://reviews.llvm.org/D20578
llvm-svn: 271277