This removes the 3 fields from the classes in Dart and instead describes
the layout in C++ via a RawTypedDataView class (as already do with
normal RawTypedData). The existing "semi" TypedDataView handle class is
changed to be a real handle class.
This decreases performance of some microbenchmarks due to field guards
not being used anymore (before the JIT could add a field guard to view classes
guarding that only normal typed data is used as backing store (and not e.g. external
typed data)
Issue https://github.com/dart-lang/sdk/issues/35154
Issue https://github.com/dart-lang/sdk/issues/31954
Change-Id: I7a0022b843a4c0fa69f53dedcc4c7bd2117cdc37
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/96806
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Prototype for `dart:ffi` on Linux/MacOS x64 in JIT mode.
`dart:ffi` is experimental and its API is likely to change in the future.
Progress and design decisions are tracked in https://github.com/dart-lang/sdk/projects/13
issue: https://github.com/dart-lang/sdk/issues/34452
Change-Id: Ifa4566388e42c8757f154741d11e303465ef305d
Cq-Include-Trybots: luci.dart.try:vm-kernel-optcounter-threshold-linux-release-x64-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-linux-release-x64-try, vm-kernel-precomp-mac-release-simarm64-try, vm-kernel-precomp-win-release-x64-try, vm-kernel-mac-debug-x64-try, vm-kernel-asan-linux-release-x64
Reviewed-on: https://dart-review.googlesource.com/c/80124
Reviewed-by: Samir Jindel <sjindel@google.com>
Auto-Submit: Daco Harkes <dacoharkes@google.com>
To avoid confusion between the heap size (includes header and rounding up) and number-of-elements size or payload size.
Change-Id: I714c4e8cec92d7ef963de39474d2a1bb23e5b4a3
Reviewed-on: https://dart-review.googlesource.com/c/92400
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Aart Bik <ajcbik@google.com>
Eliminates some symbols that were memory-reachable but not snapshot-reachable.
Compact the canonical type and type arguments tables along with the symbol table.
flutter_gallery, Android release
Total(CodeSize): 11158045 -> 11055480 (-0.92%)
Change-Id: I63bd1353906ea66c6f82a932cff57f7c25331200
Reviewed-on: https://dart-review.googlesource.com/c/92221
Reviewed-by: Siva Annamalai <asiva@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
This is the next step towards preventing compiler from directly peeking
into runtime and instead interact with runtime through a well defined
surface. The goal of the refactoring to locate all places where compiler
accesses some runtime information and partion those accesses into two
categories:
- creating objects in the host runtime (e.g. allocating strings, numbers, etc)
during compilation;
- accessing properties of the target runtime (e.g. offsets of fields) to
embed those into the generated code;
This change introduces dart::compiler and dart::compiler::target namespaces.
All code in the compiler will gradually be moved into dart::compiler namespace.
One of the motivations for this change is to be able to prevent access to
globally defined host constants like kWordSize by shadowing them in the
dart::compiler namespace.
The nested namespace dart::compiler::target hosts all information about
target runtime that compiler could access, e.g. compiler::target::kWordSize
defines word size of the target which will eventually be made different
from the host kWordSize (defined by dart::kWordSize).
The API for compiler to runtime interaction is placed into compiler_api.h.
Note that we still permit runtime to access compiler internals directly -
this is not going to be decoupled as part of this work.
Issue https://github.com/dart-lang/sdk/issues/31709
Change-Id: If4396d295879391becfa6c38d4802bbff81f5b20
Reviewed-on: https://dart-review.googlesource.com/c/90242
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
In Dart2, mixin application classes are generated by kernel and type resolution
is performed by kernel. In Dart1, using the VM parser, these tasks were done
during class and type finalization.
Change-Id: I927b1446d906ffd76ed9591c96e0d974df09f3bf
Reviewed-on: https://dart-review.googlesource.com/c/87025
Commit-Queue: Régis Crelier <regis@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
In Dart2, type bounds checking is either performed by the common front-end or
by explicitly generated code, but not by type finalization or runtime anymore,
as it was done in Dart1.
Consequently, the class BoundedType is not needed anymore, and malbounded or
malformed types are not seen by the runtime either.
Change-Id: I5d6e4c68d153d6730fa7ff7f6d9dcfa611299c16
Reviewed-on: https://dart-review.googlesource.com/c/86687
Commit-Queue: Régis Crelier <regis@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Samir Jindel <sjindel@google.com>
Demote newly introduced VM class NativeEntryData from a VM instance class
to a simple TypedData wrapper class.
Change-Id: I44aacee33500c93eb283d2d349cd7a24dd94de65
Reviewed-on: https://dart-review.googlesource.com/74323
Commit-Queue: Régis Crelier <regis@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
This class replaces a TypedData array used to describe native calls in the
constant pool of kernel bytecode.
Change-Id: Ic19c592fabde8c24f903d9c94a4d282da3e7b383
Reviewed-on: https://dart-review.googlesource.com/72242
Commit-Queue: Régis Crelier <regis@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
The info_array is needed to visit an ObjectPool's pointers, requiring the compactor to move the info_array's body before forwarding the ObjectPool's pointers. Moving the info_array inline remove this constraint on the compactor.
Also saves 3 words per ObjectPool modulo allocation size rounding.
Bug: https://github.com/dart-lang/sdk/issues/30978
Change-Id: I94de0e4b7356d46fb145efee7ab14abd7473eb4c
Reviewed-on: https://dart-review.googlesource.com/27480
Reviewed-by: Erik Corry <erikcorry@google.com>
Coverage uses the value of an execution counter to detect executed functions. However non-positive execution counter does not necessary mean that a function was never executed because we sometimes reset the counter.
Introduce additional bit on a function that is set whenever we reset positive execution counter and use this bit when generating coverage data.
Bug: https://github.com/dart-lang/sdk/issues/31326
Change-Id: I5357109603defad7e7c9415c433203f16bcf88f4
Reviewed-on: https://dart-review.googlesource.com/19760
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
The compactor copies all live objects in old space to fresh pages, places forwarding pointers in the old objects, forwards all the pointers, then frees the old pages. This has a high space overhead. It is not meant for use in production, but meant to test that the VM is properly set up to handle old-space objects moving.
Large page objects and instruction objects are not moved.
Bug: https://github.com/dart-lang/sdk/issues/30978
Change-Id: Ia42683fd5e27a33702aa5e83bece803a8b005a4b
Reviewed-on: https://dart-review.googlesource.com/13624
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Zach Anderson <zra@google.com>
Reviewed-by: Erik Corry <erikcorry@google.com>
This new object points to program wide data like string offsets,
string data etc. It also holds an array of pointers to all Script
objects corresponding scripts in the program's source table.
This new object type is required for two reasons:
1. The Script objects now have a number of fields which point to
program wide data. All Script objects point to the same data in the
VM heap. By introducing an indirection via this new object, we reduce
the number of pointers in Script objects.
2. Lazy loading of VM objects - Kernel nodes of
entities like fields and functions have a field which point to the
source file in which they are defined. This entry is an index into
the program wide source table and helps in associating
functions/fields with their actual source location. When lazy loading
functions and fields, the pre-loaded script objects in the
program's KernelProgramInfo help in associating the functions and
fields with the correct source script at load time.
Change-Id: Id863284ae7dd98b0832e5dfc115dabad1ed762d8
Reviewed-on: https://dart-review.googlesource.com/13920
Commit-Queue: Siva Chandra <sivachandra@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
Inline instance object hash code into object header on 64 bit.
64 bit objects have 32 bits of free space in the header word.
This is used for the hash code in string objects. We take it
for the default hash code on all objects that don't override
the hashCode getter.
This is both faster and a memory reduction. Eg it makes the
MegaHashCode part of the Megamorphic benchmark 6 times faster.
This is a reland of https://codereview.chromium.org/2954453002/
which fixes an issue that made script snapshots generated on
64 bit platforms incompatible with 32 bit VMs.
BUG=
R=vegorov@google.com
Review-Url: https://codereview.chromium.org/2965723002 .
Inline instance object hash code into object header on 64 bit.
64 bit objects have 32 bits of free space in the header word.
This is used for the hash code in string objects. We take it
for the default hash code on all objects that don't override
the hashCode getter.
This is both faster and a memory reduction. Eg it makes the
MegaHashCode part of the Megamorphic benchmark 6 times faster.
This is a reland of https://codereview.chromium.org/2912863006/
It fixes issues with the 32 bit compare-swap instruction on
ARM64 and fixes a fragile tree shaking test that is sensitive
to which private methods are in the core libraries.
R=kustermann@google.com, vegorov@google.com
BUG=
Review-Url: https://codereview.chromium.org/2954453002 .
I collected statistics for the sizes and capacities of growable arrays which are promoted to old-space or survive an old-space gc when running dart2js and Fasta. For these applications, the vast majority of arrays stay empty. More than half of the total object size of promoted backing arrays is backing for empty growable arrays.
Furthermore, since the overhead for an array is 3 words (header, type parameters and length), and object sizes are rounded up to an even number of words, we waste one word for all even-sized arrays.
This CL changes the growth strategy so that empty growable arrays are created with a shared, zero-sized array as backing, avoiding the allocation of a backing array if no elements are added. When the array needs to grow, it starts out at 3 and grows to double size plus one each time: 7, 15, 31, ...
A few places in the VM code need to handle these shared, zero-sized arrays specially. In particular, the Array::MakeArray function needs to allocate a new, empty array if its result is to be returned to Dart code.
Benchmarks suggest that the change improves memory usage by a few percent overall and does not significantly affect run time.
BUG=
R=erikcorry@google.com
Review-Url: https://codereview.chromium.org/2949803002 .
64 bit objects have 32 bits of free space in the header word.
This is used for the hash code in string objects. We take it
for the default hash code on all objects that don't override
the hashCode getter.
This is both faster and a memory reduction. Eg it shaves about
70% off the running time of this microbenchmark:
List list = [];
class Thing {
get hashCode => 42;
}
class Thing2 {
get hashCode => 42;
}
class Thing3 { }
class Thing4 { }
main() {
int sum = 103;
for (int i = 0; i < 10000000; i++) {
list = [];
list.add("foo");
list.add(123);
list.add(1.23);
list.add(new Object());
list.add(new Thing());
list.add(new Thing2());
list.add(new Thing3());
list.add(new Thing4());
for (int j = 0; j < 2; j++) {
sum ^= biz(list);
}
}
print(sum);
}
int biz(List list) {
int sum = 103;
for (var x in list) {
sum ^= x.hashCode;
}
return sum;
}
R=rmacnak@google.com, vegorov@google.com
BUG=
Review-Url: https://codereview.chromium.org/2912863006 .
Used for the visitors in the scavenger and marker. Each of these seems to give a few percent speed improvement for new and old space collections, respectively.
Around 0.1% total VM size increase (on ARM64).
R=erikcorry@google.com
BUG=
Review-Url: https://codereview.chromium.org/2908353002 .
This moves the hash code into the header word for strings on 64 bit
platforms. With the old layout, 9 character strings became 48-byte
objects. With the new layout you have to go to 17 characters before
you are bumped from 4 to 6 words (32 to 48 bytes).
As a side effect, the class ID field is now 16 bits on all platforms
instead of having two different sizes, and the size field is 8 bits
on all platforms.
This also paves the way for moving the hash code for instance objects
into the header, so we won't need the side-lookup in the
hash-table-of-hash-codes on 64 bit platforms.
This is a reapplication of https://codereview.chromium.org/2893553002/
after issues were fixed in https://codereview.chromium.org/2888413002/
and https://codereview.chromium.org/2896583002/R=vegorov@google.com
BUG=
Review-Url: https://codereview.chromium.org/2895183002 .
This moves the hash code into the header word for strings on 64 bit
platforms. With the old layout, 9 character strings became 48-byte
objects. With the new layout you have to go to 17 characters before
you are bumped from 4 to 6 words (32 to 48 bytes).
As a side effect, the class ID field is now 16 bits on all platforms
instead of having two different sizes, and the size field is 8 bits
on all platforms.
This also paves the way for moving the hash code for instance objects
into the header, so we won't need the side-lookup in the
hash-table-of-hash-codes on 64 bit platforms.
R=vegorov@google.com
BUG=
Review-Url: https://codereview.chromium.org/2893553002 .