We are no longer using Dart VM in a setting where this
matters as a security measure and it just complicates
portability for no benefit.
There is an indication that it is causing problems when
running Linux build of Dart VM under Docker on Mac OS X.
Fixes https://github.com/dart-lang/sdk/issues/54446
TEST=ci
Cq-Include-Trybots: luci.dart.try:vm-fuchsia-release-arm64-try,vm-fuchsia-release-x64-try
Change-Id: I11bdaa8faebaca1df6fd59097049bdaea9cb8e12
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/344581
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Slava Egorov <vegorov@google.com>
This is the same metadata system that will support async callbacks. The
main thing this does is take the trampolines that used to be JIT only,
and use them in AOT too. This is partly a safety thing (there's some
extra checks that used to be skipped on AOT), but mostly just so that
the metadata system is unified between the sync and async callbacks.
More details about the design:
https://docs.google.com/document/d/1QDjyY_6wOTOgURwpeYMKU9qEz0gKxx2MUrdruC6Kp6c/edit?usp=sharing
I split this off the async CL. Some of the comments refer to async
stuff that doesn't exist yet, but it's coming immediately after this so
I didn't update them.
Change-Id: Icd5e86934ee9ae34c2c0e2ed2bbd1b928a7184ac
TEST=ffi_callback_metadata_test.cc and CI
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/302903
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Liam Appelbe <liama@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
This region is mostly unused after loading, but it may be accessed again if
- Isolate.spawn is invoke with isolate groups disabled
- A secondary snapshot produced by splitting is loaded
- An external typed data in the snapshot is accessed (usually a kernel file)
- Likely other cases
Even if these cases did not exist, the region is often part of a shared library and so unable to be released independently.
madvise(DONT_NEED) on this region will cause the OS to release the memory in this region but keep the address space reservation and mapping. If it is touched again, it will be brought back in from the file. If it is not backed by a file, such as malloc memory, it will be brought back in as zeros and the program will likely fail.
TEST=ci
Bug: https://github.com/dart-lang/sdk/issues/44019
Bug: https://github.com/flutter/flutter/issues/92120
Change-Id: I315a049b0f7d440e181d0a5e87fa6770a2fd4f79
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/216580
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
Don't allocate zones, timeline events or profile samples in the compressible region, since these allocations don't yeild compressed pointers and are competing for a limited resource.
TEST=ci
Bug: b/196510517
Change-Id: I4fc2f0d67060f927fa10d241b15b1cae3b73d919
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/212400
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
Also switch some CQ bots using blobs to ELF. Once all embedders have migrated, we will remove blobs
support entirely.
Change-Id: Ie5e8c1187ad6c1af362b5715daafd3641bc8cc0e
Cq-Include-Trybots:luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-bare-linux-release-simarm-try,vm-kernel-precomp-mac-debug-simarm_x64-try,vm-kernel-precomp-mac-release-simarm64-try,vm-kernel-precomp-win-release-x64-try,vm-kernel-precomp-android-release-arm-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/116620
Commit-Queue: Samir Jindel <sjindel@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Instead of implementing separate aligned and unaligned memory
allocation primitives for each OS, just change the unaligned allocator
into a wrapper around the aligned primitive.
While here, we can optimize the AllocateAligned logic slightly: if we
want an N-page-aligned allocation, we only need to increase the
allocation size by N-1 pages instead of N.
Notably, this means 1-page-aligned allocations don't require any extra
alignment pages, so the new logic behaves identically as before on
Android, Fuchsia, Linux, and macOS.
On Windows, it behaves slightly differently only in that unaligned
requests used to be handled as a single VirtualAlloc call with
MEM_RESERVE | MEM_COMMIT, but now they're handled as two separate
calls (reserve *then* commit). Naively, I don't expect this matters in
practice, but if it does, we can always add a fast path for
alignment==page_size_ without affecting the OS-independent API.
Change-Id: I42b2cf5dfc6e137546d8acfb6cc8939a01687948
Reviewed-on: https://dart-review.googlesource.com/c/91081
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
This CL assigns names to vmos formatted as "isolate space type" where
isolate is the name of the isolate, space is "oldspace" or "newspace",
and type is "code" or "data".
R=asiva@google.com
Review-Url: https://codereview.chromium.org/2929203002 .
i.e. #ifndef VM_WHATEVER -> #ifndef RUNTIME_VM_WHATEVER
This lets us remove a hack from the PRESUBMIT.py script that existed
for reasons that are no longer valid, and sets us up to add some
presubmit checks for the GN build.
R=asiva@google.com, rmacnak@google.com
Review URL: https://codereview.chromium.org/2450713004 .
-Pre-mark instructions when writing the snapshot.
-Write the megamorphic miss function to the snapshot.
-Add missing ExceptionHandlers for megamorphic miss code.
-Add missing C++ entry points.
-Relocate Function and Code entry_points_ when reading precompiled snapshot.
-Don't try to load a script again when running from a precompiled snapshot.
R=asiva@google.com
Review URL: https://codereview.chromium.org//1336763002 .
With the upcoming deletion barrier, every update of a pointer field must know whether the previous value was a valid pointer.
Currently, we always use StorePointer/StoreSmi, both for initialization and updates.
Initialization, and thus the potential for overwriting garbage values, appears in three places:
1. Object::Allocate/Foo::New.
2. Creating isolate from full snapshot.
3. Allocation in generated code.
Case 1 already null-initializes all underlying memory.
Case 2 is addressed by this CL by exploiting that:
i) fresh pages are zero-filled by OS, and
ii) freelist headers use only even values.
Case 3 is remains a TODO for future CLs.
(An alternative solution for case 2 would have been to add an init_foo method for every set_foo called.)
R=iposva@google.com
Review URL: https://codereview.chromium.org//792163003
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@42584 260f80e4-7a28-3924-810f-c04153c831b5
Allocates hidden extra memory after VirtualMemory, and
verified writes are duplicated at a fixed offset.
This CL only adds the helper.
Next steps:
1. Use Reserve when reserving semi-spaces and heap pages.
2. Use Write for storing pointers (+ offset in generated code).
3. Use Accept for GC-related object lifecycle.
4. Call Verify regularly.
5. Fix failures (= places where we forget/ignore write barriers).
Review URL: https://codereview.chromium.org//641243004
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@41399 260f80e4-7a28-3924-810f-c04153c831b5
Change executable pages to be read/execute but not writable by default.
All pages are made temporarily writable just before a full GC, because both
the mark and sweep phases write to the pages. When allocating in a page and
when patching code, the pages are made temporarily writable.
The order of allocation of Code and Instructions objects is changed so that
a GC will not occur after Instructions is allocated. (A full GC would
render the Instructions unwritable.) A scoped object is used to make memory
protection simpler.
Original CL: https://codereview.chromium.org/106593002/
I added a cc test that is expected to crash.
R=srdjan@google.com
Review URL: https://codereview.chromium.org//136563002
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@32493 260f80e4-7a28-3924-810f-c04153c831b5
Vyacheslav Egorov