Summary:
This CL introduces the 32 & 64-bit primary allocators, and associated
Local Cache. While the general idea is mostly similar to what exists
in sanitizer_common, it departs from the original code somewhat
significantly:
- the 64-bit primary no longer uses a free array at the end of a region
but uses batches of free blocks in region 0, allowing for a
convergence with the 32-bit primary behavior;
- as a result, there is only one (templated) local cache type for both
primary allocators, and memory reclaiming can be implemented similarly
for the 32-bit & 64-bit platforms;
- 64-bit primary regions are handled a bit differently: we do not
reserve 4TB of memory that we split, but reserve `NumClasses *
2^RegionSizeLog`, each region being offseted by a random number of
pages from its computed base. A side effect of this is that the 64-bit
primary works on 32-bit platform (I don't think we want to encourage
it but it's an interesting side effect);
Reviewers: vitalybuka, eugenis, morehouse, hctim
Reviewed By: morehouse
Subscribers: srhines, mgorny, delcypher, jfb, #sanitizers, llvm-commits
Tags: #llvm, #sanitizers
Differential Revision: https://reviews.llvm.org/D61745
llvm-svn: 361159
Summary:
The Secondary allocator wraps the platform allocation primitives. It is
meant to be used for larger sizes that the Primary can't fullfill, as
it will be slower, and sizes are multiple of the system page size.
This also changes some of the existing code, notably the opaque
platform data being passed to the platform specific functions: we can
shave a couple of syscalls on Fuchsia by storing additional data (this
addresses a TODO).
Reviewers: eugenis, vitalybuka, hctim, morehouse
Reviewed By: morehouse
Subscribers: mgorny, delcypher, jfb, #sanitizers, llvm-commits
Tags: #llvm, #sanitizers
Differential Revision: https://reviews.llvm.org/D60787
llvm-svn: 359097
Kostya Kortchinsky