Previously, before switching to compact encoding of bytecode
instructions, we had to align bytecode instructions by 4.
Since that time sections of bytecode binary were aligned.
However, this alignment doesn't work well in AOT mode if dill file
contains both bytecode and AST, as other metadata (such as obfuscation
prohibitions) may precede bytecode metadata and may make the whole
bytecode binary misaligned.
This results in incorrect calculation of section offsets,
failed assertion
assert(writer.offset - start == section.offset);
and VM may fail to load bytecode binary with error
bytecode_reader.cc: 1368: error: unreachable code
In order to fix these problems, extra alignment of bytecode
sections is removed.
Change-Id: Iaa3b7c46999615aaa446781a7018db409261ead8
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/123686
Reviewed-by: Régis Crelier <regis@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Previously, bytecode generator was allocating a bunch of objects
eagerly when starting bytecode generation for a member. Most of these
objects are maps and lists which are needed only under certain
circumstances. With this change these objects are allocated more lazily,
only when needed.
Also, this CL fixes crash in LinkReader.setOffset when reading/dumping
bytecode.
Change-Id: I11c561e4f00c456e92f42530d3d4e6008b5f5daf
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/122407
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Instead of keeping offsets of bytecode declarations in a map,
offset is now stored in a field of a base class for all declarations.
This saves certain number of map lookups while serializing bytecode.
Also, calls to a rather expensive Map.putIfAbsent are removed.
Change-Id: I036fbb0e1d8afc6e402709a0a1eafb0e50a2c25a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/122170
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Size of a large application:
Before: 26628600
After: 21480120 (-19.3%)
Size of snapshots:
isolate_snapshot_framework.bin
Before: 9322496
After: 6782976 (-27.2%)
isolate_snapshot_product_framework.bin
Before: 9166848
After: 6602752 (-27.9%)
Regressions in tests:
1) Test language_2/type_alias_equality_test/04 fails similarly to default mode, as VM
does not implement comparison of function types according to the specification.
Previously this test was passing as function types were canonicalized in bytecode,
which was not always correct. This CL fixes the problem with canonicalization of
function types in bytecode and the test starts failing again.
2) Tests standalone_2/entrypoints_verification_test, standalone_2/io/test_extension_test,
standalone_2/io/test_extension_fail_test fail as native extensions are not supported
in bytecode yet. These tests start passing after df5e7aac17,
which switched bytecode tests to kernel service (on x64), because kernel service doesn't
drop ASTs. This CL switches from reading AST library declarations to bytecode even if
AST is not removed, so tests fail again.
Change-Id: I8b7ba44bfa49d0b1599b2509553ff7c831a4e244
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/104700
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Régis Crelier <regis@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
This change replaces kernel AST declarations of fields and functions
with bytecode declarations.
Size of dilp files is reduced by 11-12%.
Startup latency:
Time to the first full frame: 1.945s -> 1.687s
FinalizeClass: 554ms -> 277ms
FinishClassLoading: 296ms -> 156ms
There are following regressions in bytecode mode, which will be fixed
in future:
* dart:mirrors are not supported yet (implementation of mirrors relies
on reading kernel AST in certain cases).
As the result, lib_2/mirrors/* tests fail.
* native extensions are not supported yet (annotations on libraries
and classes in AST are cleaned up as they could reference members
which are now removed from AST).
As the result, standalone_2/entrypoints_verification_test test fails.
* language_2/spread_collections/const_error_test/* tests fail
due to https://github.com/dart-lang/sdk/issues/36286.
Change-Id: I5130f401fd7b84038b136136e7ccc1a6e51b6cea
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/97561
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
* Type arguments are moved to global object table (and de-duplicated).
* Finalize non-recursive generic types at bytecode generation time.
* Constants are moved to global object table (and de-duplicated).
* ICData creation is avoided for direct calls.
* Interface calls reference target member instead of selector name.
Size of a dilp files: 17868K => 15896K (-11%).
Change-Id: I0c9bf338137a0fae6ed90ab6b125ed2b24a1a8ad
Reviewed-on: https://dart-review.googlesource.com/c/91108
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Zach Anderson <zra@google.com>
Reviewed-by: Régis Crelier <regis@google.com>
This is a major revamp of bytecode metadata format. Now bytecode has
its own serialization mechanisms.
This CL adds 'bytecode component' metadata, which contains bytecode
object table and string table. All references from bytecode (constant
pools) to libraries, classes, members, types and strings now have a new
format. References to frequently used objects are represented as indices
in object table, while rarely used objects are written inline.
This allows VM to cache frequently used objects while reading bytecode.
Representation of strings is aligned with VM - string characters are
stored in separate pools of one-byte and two-byte strings. This allows
VM to avoid UTF-8 decoding and extra copying.
Closure declarations are now explicit. Type parameters no longer require
enslosing scopes when reading/writing them.
Benchmarks:
GenKernelKernelReadAllBytecode (Intel Core i5) +29.84%
GenKernelKernelReadAllBytecode (Intel Xeon) +28.74%
Change-Id: I4b80009733a8f8c038264af74f97c4e094b9e311
Reviewed-on: https://dart-review.googlesource.com/c/85469
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Régis Crelier <regis@google.com>
Reviewed-by: Zach Anderson <zra@google.com>
Alexander Markov