Since the kernel reading helpers have been extended to not only work
with a kernel blob in C heap, but also work based on a [TypedData]
buffer in the VM heap, access to the [TypedData] buffer is on the hot
path now.
This hot path is slowing things down considerably, in particular due
to NoSafepoingScope's.
This CL removes a critical NoSafepoingScope when accessing the
[TypedData] in read-only mode. It also allows passing in the [Thread]
directly, to avoid TLS lookups.
Issue https://github.com/dart-lang/sdk/issues/32603
Change-Id: I91955bea5cd4eddbbd21c5d3bc6813504c2cece9
Reviewed-on: https://dart-review.googlesource.com/47222
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Translate assert statements in async functions. The translation of
the condition subexpression can produce a sequence of statements that
have been hoisted out of it. These need to be guarded so they are
executed only when asserts are enabled.
For this purpose, we introduce an AssertBlock. The semantics of the
assert block:
assert { s0; ...; sn; }
is the same as:
if (assertsEnabled) { s0; ...; sn; }
where assertsEnabled is a more primitive nullary expression that is
true iff. assertions are enabled. We chose not to encode this using a
construct like assertsEnabled because (1) we would have to support it
appearing as an arbitrary expression which we don't currently need
and (2) it requires deeper pattern matching to detect and skip the
guarded code when desired.
The translation is more complicated because if there is a message
subexpression in an assert, it is conditionally evaluated only if the
assert's condition is false.
Fixes https://github.com/dart-lang/sdk/issues/28498
Change-Id: I0912a57104ede3160533e49f65b6fb79b76f1500
Reviewed-on: https://dart-review.googlesource.com/46442
Commit-Queue: Kevin Millikin <kmillikin@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
This simplifies figuring out what went wrong from just
debugging output in some cases.
Change-Id: Ie7a775c57fb691d6bd3ca1c70a04fb6cbe9e0875
Reviewed-on: https://dart-review.googlesource.com/43060
Reviewed-by: Jens Johansen <jensj@google.com>
Before: Kernel static errors were represented by throwing a distinguished
error or else by calling a distinguished library const constructor.
Now: Kernel static errors are represented by InvalidExpression. To support
error reporting, InvalidExpression has an optional message and a file
offset. A back end can choose to signal these errors at any time; for
example, when deserializing the binary, or when compiling the procedure
containing the static error, or when the erroneous expression is evaluated
at run time.
InvalidStatement is removed because it can be encoded as ExpressionStatement
of InvalidExpression.
Future work:
* supporting static errors where an expression cannot appear in the AST
* allowing InvalidExpression to contain an Expression for error recovery
* adding a top-level list of static errors and warnings to the binary
Bug: https://github.com/dart-lang/sdk/issues/29840
Change-Id: Ifdfe9a76cee6cefed28061bf245be70531d2f413
Reviewed-on: https://dart-review.googlesource.com/31320
Commit-Queue: Kevin Millikin <kmillikin@google.com>
Reviewed-by: Dan Rubel <danrubel@google.com>
Reviewed-by: Konstantin Shcheglov <scheglov@google.com>
Assert initializers in Dart may be compiled directly to this form of initializer,
rather than through local initializers as is done now.
Bug:
Change-Id: Ia149ea3d1df5d1dc18be5636801604ffaf7ca7d8
Reviewed-on: https://dart-review.googlesource.com/14760
Commit-Queue: Samir Jindel <sjindel@google.com>
Reviewed-by: Kevin Millikin <kmillikin@google.com>
The introduced "constants" transformation can evaluate constant expressions. The
original use-sites of constant expressions are replaced by a new [ConstantExpression]
node, which points to a subclass of a new [Constant] class hierarchy. Constant
[Field]s and [VariableDeclarations]s will be removed, since all use-sites are
re-written.
The [Constant] class hierarchy is, similarly to the [DartType] class hierarchy, not
part of the AST tree (also has no parent pointer). The constants form a
DAG (directed acyclic graph).
There is no canonicalization requirement of the [Constant] objects referenced by the
AST (via [ConstantExpression]). Although it is beneficial to canonicalize them during
construction, since it reduces time spent in operator==/hashCode.
This CL furthermore adds support for a constant table in the binary format. Similarly
to [String]s, we canonicalize the constants before writing the table to the binary.
The constant table entries in the binary are written in a post-order way, to ensure
easy construction on the backend side.
The text format will be augmented with a "constants { ... }" section at the end,
which lists the constants in the same order as in the binary format.
The transformation can be used by those backends who choose to do so. It is not
enabled by default atm. It should therefore not affect analyzer, fasta or other
components.
Change-Id: I57cd9624fedcf537ab6870db76246149647bed21
Reviewed-on: https://dart-review.googlesource.com/14382
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Kevin Millikin <kmillikin@google.com>
This change brings down core snapshot size by ~750KB, and brings
down app-jit snapshot size of simple "Hello, World" dart script by
~650KB. The bot cycle times will also come down by around ~20%.
Change-Id: I2a01c98bedc7ebfa2a653983995486a71504daf3
Reviewed-on: https://dart-review.googlesource.com/16323
Commit-Queue: Siva Chandra <sivachandra@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
Reviewed-by: Jens Johansen <jensj@google.com>
This CL adds internal binary format version to kernel binaries.
Kernel readers in the front-end and VM verify that the reader's format
version matches the format version in the binary file.
This improves detection and diagnostics of stale kernel binary files.
Change-Id: Ic69b16057397a84627040bdd6420ffa1852a4b3f
Reviewed-on: https://dart-review.googlesource.com/13280
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Jens Johansen <jensj@google.com>
Reviewed-by: Kevin Millikin <kmillikin@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Devirtualization optimization now adds metadata to kernel AST instead
of transforming nodes to Direct* ones. The direct call metadata
provides information about checking receiver for null, while
Direct* kernel nodes do not support null checking.
VM's kernel binary loader is extended to extract arbitrary metadata
from kernel binaries and keep it for flow graph builder.
Kernel flow graph builder is extended to take direct call metadata
into account and generate CheckNull/StaticCall instructions
for devirtualized PropertyGet, PropertySet and MethodInvocation nodes.
Issue: https://github.com/dart-lang/sdk/issues/30480
Change-Id: I57f56fbf4a8981d33b1571c0d93105cf8ca71d76
Reviewed-on: https://dart-review.googlesource.com/12260
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Before this change, each function and field had its own kernel data blob
in the VM heap. With this change, the entire kernel data of a library is
stored as one single blob in the VM heap. Functions and fields store an
offset which points to the kernel data, specific to them, in that single
blob.
The pointer to the kernel data for a library is saved in two places:
1. With the library objects themselves.
2. With all the patch classes of the library.
3. With the patch classes created during hot reload.
Change-Id: Ie03e738c4d20f16056a5ef04341b75506fda9c60
Bug:
Reviewed-on: https://dart-review.googlesource.com/6601
Commit-Queue: Siva Chandra <sivachandra@google.com>
Reviewed-by: Jens Johansen <jensj@google.com>
Before this CL we skipped procedure bodies in kernel_loader.cc by
parsing the body (but not storing anything).
With this CL we now skip them directly (i.e. don't read them at all)
in kernel_loader.cc by using the newly available extra indexes in kernel.
Change-Id: I48cf0599b2a85102c9008ff7c455785151ef3c9c
Reviewed-on: https://dart-review.googlesource.com/5764
Commit-Queue: Jens Johansen <jensj@google.com>
Reviewed-by: Samir Jindel <sjindel@google.com>
Currently serializing the ast for kernel is done in two passe:
1) Scan the program to find and index all strings. These are then
sorted based on frequency and assigned an id. All string-
references are refering to that id. As small numbers use less
space in the binary than big numbers, sorting the numbers by
frequency saves a certain amount of space.
In addition the string indexing is "hijacked" for the
"LimitedBinaryPrinter" to also perform some CanonicalName
re-indexing.
2) We then serialize the entire thing.
This CL gets rid of a pass by not indexing the strings up-front.
Whenever it is asked to serialize a string it adds it to the index
(if not already there). The serialization is otherwise the same.
This means that:
1) Strings are not sorted by frequency, i.e. the binary output size
can by bigger (numbers below).
2) The stringindex and canonical names are moved to the end of the
binary instead of the front. As we still need it up front for
deserialization some additional data is added to the
ProgramIndex.
3) The "hijacking" done in "LimitedBinaryPrinter" is replaced by
an alternative.
4) We don't spend time on walking the tree twice.
The cost is the binary size. Compiling helloworld with fasta,
as well as looking at outline.dill, platform.dill and
vmservice_io.dill reveals these numbers:
* helloworld.dill is 0.657248732% bigger (26573 bytes)
* outline.dill is 1.686911399% bigger (9395 bytes)
* platform.dill is 0.657062238% bigger (26565 bytes)
* vmservice_io.dill is 0.44991899% bigger (19147 bytes)
The cost does thus not appear to be very big.
The gain is the serialization time.
From 20 runs of an instrumented VM/serialization, running numbers
through calculations stolens from ministat
(https://www.freebsd.org/cgi/man.cgi?query=ministat) reveals the
following:
* Serialization time: -21.69% +/- 1.44%
* Total time spend in relevant parts of bootstrap_nocore.cc,
dart_api_impl.cc (Dart_LoadKernel), bootstrap_nocore.cc,
dart_api_impl.cc (LoadKernelProgram) as well as serialization:
-14.01% +/- 1.58%
From 5 runs of
"time python tools/test.py -m release -cdartk language -j6"
(again run through ministat calculations):
* real: -4.18% +/- 0.5%
* user: -4.2% +/- 0.29%
* sys: No difference at 95%
* user+sys: -3.3% +/- 0.36%
Change-Id: I1c220eac083496994f0a9f1e2a2445b3707c9a93
Reviewed-on: https://dart-review.googlesource.com/2880
Reviewed-by: Samir Jindel <sjindel@google.com>
New folder structure (nested under vm/):
- compiler/
- jit/ - JIT specific code
- aot/ - AOT specific code
- backend/ - all middle-end and back-end code (IL, flow graph)
- assembler/ - assemblers and disassemblers
- frontend/ - front ends (AST -> IL, Kernel -> IL)
compiler/README.md would be the documentation root for the compiler
pipeline
Bug: https://github.com/dart-lang/sdk/issues/30575
Change-Id: I2dfd9688793bff737f7632ddc77fca766875ce36
Reviewed-on: https://dart-review.googlesource.com/2940
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
This CL copies the kernel bodies for all functions and
fields into the VM heap. The function bodies in the VM
heap are then used when compiling the flowgraphs.
This theoretically means that the malloc'd data can be
freed and that snapshotting from kernel could possibly
work, though it hasn't been tested.
R=kmillikin@google.com
Review-Url: https://codereview.chromium.org/2972343002 .
This CL allows for streaming big parts of the binary,
i.e. without using the AST nodes.
It is thus a stepping-stone in getting rid of the AST nodes in the VM.
Generally, all Expressions except "FunctionExpression",
and all Statements except "FunctionDeclaration" can be streamed.
There are currently not streamed because they create new functions,
which has a pointer to an AstNode (which we don't have when streaming).
Once we no longer need AstNodes at all these can be streamed as well.
This is, I think, mostly a matter of streaming the ScopeBuilder as well,
something that is not currently done.
The way the streaming is build, one has to stream an entire subtree.
That means, that if an expression (or statement), A, that is generally
streamable contains an expression or a statement, B, that is not streamable,
A cannot be streamed.
The way this is build is by marking AstNodes as streamable or not
("cannot_stream_" field). That way we know up front whether we can stream
a subtree or not.
The streaming is done via "kernel_binary_flowgraph".
In this file there are many obvious comments, e.g.
```
TokenPosition position = ReadPosition(); // read position.
```
This has been done in an attempt to add a comment to everything that
reads from the binary to make it stand out more.
All changes from kernel_to_il up to and including May 2nd 2017
should be included.
R=kmillikin@google.com
Review-Url: https://codereview.chromium.org/2854393002 .
In the VM's Kernel representation, introduce wrapper classes for
string and name indexes so it is obvious which one is which. For
convenience there is an implicit conversion so that they can each be
used where an int is allowed. However, there is no implicit
conversion _to_ either of these types.
BUG=
R=vegorov@google.com
Review-Url: https://codereview.chromium.org/2860823002 .
The canonical name table is copied into a typed data array in the VM's
heap. The encoding is the same as in the binary except that the
integer indexes are fixed-size.
Canonical names are now integer indexes instead of objects allocated
in the C++ heap.
BUG=
R=jensj@google.com, vegorov@google.com
Review-Url: https://codereview.chromium.org/2853423002 .
Copy the Kernel string offsets into a uint32 array in the VM's heap.
This avoids allocating small string objects with new and avoids having
a table of the canonical strings.
Instead of an offset and a size, strings are now represented as
indexes into the string table in the heap. The start offset of string
N is found at byte offset N*4 because it is a uint32, and the end
offset is found at byte offset (N+1)*4. The strings themselves are
just integer indexes instead of pointers.
In the stream flow graph builder, string access is all random access.
R=jensj@google.com, vegorov@google.com
Review-Url: https://codereview.chromium.org/2852943003 .
- Instead of a pointer to new'd memory, Kernel strings now have an
offset from the start of the string data.
- When the streaming reader encounters the string data it records the
offset from the start of the binary. This offset is stored in the
Kernel Program and is used to compute the offset for strings.
- When a KernelReader is constructed, the string data is copied into a
Uint8 array in the VM's heap.
- A pointer to the string data is put into every Kernel script so it
can be used for constructing VM strings at compile time.
The source table does not use Kernel strings any more because those
strings are not found in the raw string data. Instead, the source
table uses new'd buffers for strings (but this will be cleaned up
separately).
R=jensj@google.com
Review-Url: https://codereview.chromium.org/2820363002 .
Martin Kustermann