FFI trampolines are stored in the global object pool and not
reachable either via class or via the closure functions in the
object store.
Fixes https://github.com/dart-lang/sdk/issues/41261
Bug: https://github.com/dart-lang/sdk/issues/41052
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-release-x64-try,vm-kernel-precomp-linux-product-x64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-linux-release-simarm_x64-try,vm-kernel-precomp-mac-release-simarm64-try,vm-kernel-precomp-win-release-x64-try
Change-Id: I3e1551dba80a2fd418946d7449467317463c2c61
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/141882
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
In particular, don't serialize a function if its code is used by the
dispatch table, but there's no need for the function object itself
at runtime like dynamic lookup or dynamic invocation forwarders.
However, just because the owning function is not needed at runtime,
it may be used during serialization for things like assembly label
creation. Thus, instead of just clearing out the Code's owner field,
we add a new WeakSerializationReference (WSR) object whose target is
the original contents of the owner field. The WSR allows the
serializer to access the original owner, but also signals to the
serializer that the target should not be serialized in AOT snapshots
unless there are additional strong (non-WSR) references.
If no strong references are found, then the references to the WSR
in the snapshot are replaced with a reference to a WSR that only
contains the class ID of the original target. The serializer creates
only one WSR per class ID.
If strong references are found, then the target is still serialized.
In this case, the WSR is dropped entirely and any reference to it is
replaced with a direct reference to the serialized target. Thus, WSRs
only exist in the precompiled runtime for targets with no strong
references.
Changes on the Flutter gallery in release mode:
arm7: total size -1.10%, isolate size -6.08%
arm8: total size -1.16%, isolate size -6.09%
Bug: https://github.com/dart-lang/sdk/issues/41052
Change-Id: I5b435ca71ef85f50fe3484789087471a91aa4fe2
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-release-x64-try,vm-kernel-precomp-linux-product-x64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-linux-release-simarm_x64-try,vm-kernel-precomp-mac-release-simarm64-try,vm-kernel-precomp-win-release-x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/137104
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Also check the flag in all code that possibly deduplicate instructions
or needs to know whether instructions may have been deduplicated, so we
can test this code in non-product builds by turning on the flag.
Change-Id: Iefd1aa13a0f5a8a1cd51b547d554c9ae8e7410ac
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/134820
Commit-Queue: Teagan Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
index to fix VMs coverage issue
This CL fixes the VM not always reporting coverage for mixin usages
properly.
* When asking the VM for coverage you can do it in one of two ways
* Ask the VM for coverage for everything; or
* Ask the VM for coverage for a specific script
* Asking the VM for coverage for everything works perfectly fine.
The VM goes through everything and reports coverage correctly.
* Asking the VM for coverage for a specific script (which is, at least
now, what the flutter tools does) doesn't work in the simple mixin
case described at http://dartbug.com/39779: The VM goes through the
libraries, asking for the list of scripts they "know about",
and checks for matches against what you asked for.
In this case, when asking for 'master.dart', the library for
'lib.dart' says no when it shouldn't --- because of the way the mixin
transformation works the content is actually in lib.dart.
This CL updates the content of the field 'sourceReferences' on Library
to fix the issue.
Fixes#39779
Change-Id: I0c38a323c81d1784ade704837b67ece549fc95d2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/128585
Commit-Queue: Jens Johansen <jensj@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Johnni Winther <johnniwinther@google.com>
There's just one case where we can't get the offset for Instructions
from somewhere else, and that's when we reset active_instructions_ to
instructions_ in Code::Enable(). Thus, we add a caching field for the
uncached offset to RawCode, but only when the active_instructions_
field is added (when not running in the precompiled runtime).
We also output the unchecked offset in snapshots for Code objects so
we can recalculate the entry point cache on loading. (For full JIT
snapshots, we output both the cached offset and the offset for
active_instructions_.)
Bug: https://github.com/dart-lang/sdk/issues/38451
Change-Id: I78572ec83d1574b00820df148bccb57e5c79eaaa
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/125400
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Teagan Strickland <sstrickl@google.com>
When we are writing a snapshot, canonicalize all entries within
CompressedStackMaps payloads. We do this by creating a global table
of stack map information (bit counts + bit payload) that we store
in the isolate object store, and then for each existing CSM, we
replace it with an alternate version that refers to the global table.
This gets back some of the canonicalization we lost when we moved from
individual StackMap objects to per-Code CompressedStackMaps objects.
Here, we also represent the global table as a CompressedStackMaps
object. This means that there are three types of CompressedStackMaps:
* The original version that directly contains all entry information.
* The version where each entry is just the PC offset delta and an
offset into the global table payload.
* A version representing the global table where the entries are like
the original version except they don't contain a PC offset delta.
-----
The impact on AOT snapshot size when compiling the Flutter Gallery
in release mode:
armv7: Total size -0.88% (Isolate RO: -5.05%, Isolate snapshot: +0.00%)
armv8: Total size -1.04% (Isolate RO: -5.28%, Isolate snapshot: +0.00%)
-----
Bug: https://github.com/dart-lang/sdk/issues/35274
Change-Id: I1ce0f8b3cc58e2f11584f3c218e0fdf8984b799b
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-simarm_x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/120667
Commit-Queue: Teagan Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Currently the switchable calls require there to be a unique PC -> Code
-> Function mapping to re-construct the arguments descriptor which was
lost when transitioning from unlinked to monormophic.
=> This prevents instruction deuplication in bare mode for those
functions, because the PC -> Function mapping is amgiguous (the
frames don't have a Code object on the stack we can use)
This CL preserves the (name, args-descriptor) per switchable call site when we
go from unlinked to monomorphic state by remembering it in a map. When
transitioning out of monomorphic we can use this map to re-construct the
name and arguments descriptor (and delete the map entry).
Flutter gallery release size impact:
* arm64: total -2.33 % (-3.62% RX)
* arm: total -1.72 % (-2.65% RX)
From local testing it seems like running flutter gallery in profile mode
and connecting via observatory the memory consumed by UnlinkedCall
instances seems minimal.
Change-Id: I55902e6f11c9941493c610ed18f26bc5fc3dcf59
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/121421
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
Fixes an assumption that CompressedStackMapsIterator::Find() is never
passed a PC offset of 0. Adds back an ASSERT that was dropped which checks
for specific cases where a given PC offset does not have a stack map entry.
Original commit message:
Lifting the PC offset in a2bb730 was a small, lightweight change that
gave us big gains, at least on 32-bit architectures. Here, we make
much more invasive changes that will improve the amount of memory used
by the information previously stored in StackMap objects.
Instead of allocating separate objects for StackMaps, we instead compress
all StackMap information for a given Code object into a single object
(CompressedStackMaps, or CSM for short). This replaces the Array used to
store PC offsets (as Smis) and the individual StackMap objects.
While we lose all canonicalization for individual StackMap entries, the
drop in space required to store stack map information more than offsets that.
-----
The impact on AOT snapshot size when compiling the Flutter Gallery
in release mode:
armv7: Total size -2.58% (Isolate RO: +14.46%, Isolate snapshot: -22.93%)
armv8: Total size -1.85% (Isolate RO: +15.69%, Isolate snapshot: -22.97%)
The impact on in-memory, not on-disk, size for the Flutter Gallery as seen
in the Observatory while running a profile (not release) build:
armv7: Drops from 7.1 MB to 6.2MB (-0.9 MB)
armv8: Drops from 13.5MB to 11.7MB (-1.8 MB)
-----
Bug: https://github.com/dart-lang/sdk/issues/35274, https://github.com/dart-lang/sdk/issues/38873
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-simarm_x64-try,vm-kernel-mac-debug-simdbc64-try
Change-Id: I111b129b0ed64f03184370bceb7cda69d5d4b3c9
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/121700
Commit-Queue: Teagan Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
This reverts commit d77f4913a1.
Reason for revert: large number of flaky crashes on flakiness dashboard (https://github.com/dart-lang/sdk/issues/38873); crashes on vm-kernel-mac-debug-simdbc64 bot.
Original change's description:
> [vm/compiler] Further compress the information previously in StackMaps.
>
> Lifting the PC offset in a2bb730 was a small, lightweight change that
> gave us big gains, at least on 32-bit architectures. Here, we make
> much more invasive changes that will improve the amount of memory used
> by the information previously stored in StackMap objects.
>
> Instead of allocating separate objects for StackMaps, we instead compress
> all StackMap information for a given Code object into a single object
> (CompressedStackMaps, or CSM for short). This replaces the Array used to
> store PC offsets (as Smis) and the individual StackMap objects.
>
> While we lose all canonicalization for individual StackMap entries, the
> drop in space required to store stack map information more than offsets that.
>
> -----
>
> The impact on AOT snapshot size when compiling the Flutter Gallery
> in release mode:
>
> armv7: Total size -2.58% (Isolate RO: +14.46%, Isolate snapshot: -22.93%)
> armv8: Total size -1.85% (Isolate RO: +15.69%, Isolate snapshot: -22.97%)
>
> The impact on in-memory, not on-disk, size for the Flutter Gallery as seen
> in the Observatory while running a profile (not release) build:
>
> armv7: Drops from 7.1 MB to 6.2MB (-0.9 MB)
> armv8: Drops from 13.5MB to 11.7MB (-1.8 MB)
>
> -----
>
> Bug: https://github.com/dart-lang/sdk/issues/35274
> Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-simarm_x64-try
> Change-Id: Ie3bb898d557215146260a560423f5fa27bdff512
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/119640
> Commit-Queue: Teagan Strickland <sstrickl@google.com>
> Reviewed-by: Martin Kustermann <kustermann@google.com>
> Reviewed-by: Ryan Macnak <rmacnak@google.com>
TBR=kustermann@google.com,rmacnak@google.com,sstrickl@google.com
# Not skipping CQ checks because original CL landed > 1 day ago.
Bug: https://github.com/dart-lang/sdk/issues/35274
Change-Id: Ib844b4d52e3aa4aca62a896cfe349c680bda7461
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try, vm-kernel-precomp-linux-debug-simarm_x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/121642
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Lifting the PC offset in a2bb730 was a small, lightweight change that
gave us big gains, at least on 32-bit architectures. Here, we make
much more invasive changes that will improve the amount of memory used
by the information previously stored in StackMap objects.
Instead of allocating separate objects for StackMaps, we instead compress
all StackMap information for a given Code object into a single object
(CompressedStackMaps, or CSM for short). This replaces the Array used to
store PC offsets (as Smis) and the individual StackMap objects.
While we lose all canonicalization for individual StackMap entries, the
drop in space required to store stack map information more than offsets that.
-----
The impact on AOT snapshot size when compiling the Flutter Gallery
in release mode:
armv7: Total size -2.58% (Isolate RO: +14.46%, Isolate snapshot: -22.93%)
armv8: Total size -1.85% (Isolate RO: +15.69%, Isolate snapshot: -22.97%)
The impact on in-memory, not on-disk, size for the Flutter Gallery as seen
in the Observatory while running a profile (not release) build:
armv7: Drops from 7.1 MB to 6.2MB (-0.9 MB)
armv8: Drops from 13.5MB to 11.7MB (-1.8 MB)
-----
Bug: https://github.com/dart-lang/sdk/issues/35274
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-simarm_x64-try
Change-Id: Ie3bb898d557215146260a560423f5fa27bdff512
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/119640
Commit-Queue: Teagan Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Instead of storing the PC offset inside the StackMap object, store it instead
in the `Array` containing `StackMap`s in `Code` objects. That is, the `Array`
provided by `Code::stackmaps()` no longer contains just `StackMap` objects, but
instead contains `Smi`s and `StackMap` objects in alternating fashion. Each
`Smi` is the PC offset for the `StackMap` object that follows.
This ends up changing very little code outside of `StackMap`,
`Code::GetStackMap`, and `StackMapTableBuilder`, as there are only two types of
`StackMap` users:
* Users that call `Code::GetStackMap` already have the PC offset.
* Users that call Code::stackmaps() can just fetch the PC offset from the
returned `Array` instead.
On 64-bit architectures, we will use more space to represent the PC offset
as a Smi in the Array than the old uint32_t field. However, the drop in total
number of StackMap objects due to an increased ability to canonicalize
them should offset this. On 32-bit architectures, we can only represent
30 bit PC offsets, not 32 bit PC offsets, but that shouldn't be a problem
in practice except for pathological cases.
_Numbers from building the Flutter gallery in android_release mode_
Since PC offsets are no longer in the `StackMap` objects, this enables
a lot more canonicalization than before. Previously, we generated
49379 `StackMap`s, but now we only generate 16139 `StackMap`s, just under
a third of the original number. This is because there were a lot of
`StackMap`s that differed only in their PC offset, and now they can
be canonicalized into the same `StackMap` object.
When building the Flutter gallery with android_release, the app.so size
drops from 11276896 bytes to 10908256 bytes, a difference of 368640
bytes, or 3.27%.
Using the AOT snapshot profiling support, we see the following drops:
Heap snapshot size drops from 10.7 MB to 10.4 MB.
`Code` | Before | After | Difference
---------------------------------------------------------
Shallow size | 352363 | 352363 | 0
Retained size | 9114801 | 8796064 | -318737
Percent of snapshot | 81.2% | 80.7% | -0.5%
`(RO)StackMap` | Before | After | Difference
---------------------------------------------------------
Shallow size | 49381 | 16141 | -33240
Retained size | 893965 | 286613 | -607352
Percent of snapshot | 7.97% | 2.63% | -5.34%
`StackMap` | Before | After | Difference
---------------------------------------------------------
Shallow size | 844584 | 270472 | -574112
Retained size | 844584 | 270472 | -574112
Percent of snapshot | 7.53% | 2.48% | -5.05%
As we'd expect from the `StackMap` numbers above, we end up using a little
under a third of the space for `StackMap`s. We actually use even less space
(32.0% of the original) than the drop in `StackMap` numbers (32.7%), because
each `RawStackMap` instance is 32 bits smaller due to dropping the `pc_offset_`
field. Note that even though these PC offsets now show up in the
`Code::stackmaps()` `Array`, we can see this is still a net drop in space used
by looking at the retained size of `Code` objects.
Bug: https://github.com/dart-lang/sdk/issues/35274
Change-Id: I0910a43e7a5a7e2e721676209196be1884c5a71c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/119147
Commit-Queue: Teagan Strickland <sstrickl@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
This for instance allows the VM to include all patches
(e.g. the previously missing `runtime/lib/date_patch.dart`)
in what's returned from `LoadedScripts()`.
Over time this also allows for `LoadedScripts()` to be simplified and
become faster (it's currently something like O(m + m*n) where m is the
number of results in DictionaryIterator(*this) and n is the number of
returned scripts).
Change-Id: I4b5a6a0fe666b774fc0987d099ed02e81ac97b43
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/98660
Commit-Queue: Jens Johansen <jensj@google.com>
Reviewed-by: Kevin Millikin <kmillikin@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
This is the final CL which adds a new --use-bare-instructions flag to
the VM.
If this flag is set during AOT compilation, we will:
* Build one global object pool (abbr: GOP) which all code objects
share. This gop will be stored in the object store. The PP register
is populated in the enter dart stub and it is restored when
returning from native calls.
* Gets rid of the CODE_REG/PP slots from the dart frames. Instead the
compiled code uses the global object pool, which is always in PP.
* Starts emitting pc-relative calls for calls between two dart
functions or when invoking a stub.
Limitation: We only emit pc-relative calls between two code objects
in the same isolate (this is because the image writer is writing
instruction objects for vm-isolate/main-isolate seperately)
* We do compile-time relocation of those static calls after the
precompiler has finished its work, but before writing the snapshot.
This patches all the instruction objects with pc-relative calls to
have the right .text distance.
* We emit a sorted list of code objects in ObjectStore::reverse_code_table,
which will be used by the AOT runtime to go back from PC to Code
objects (where all metadata, e.g. stack maps, catch entry moves, pc
descriptors are available).
Issue https://github.com/dart-lang/sdk/issues/33274
Change-Id: I6c5dd2b1571e3a889b27e804a24c2986c71e03b6
Reviewed-on: https://dart-review.googlesource.com/c/85769
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Previously we tried to rely on the assumption that all variables would be
boxed - so the machinery for setting correct catch-entry state only
supported tagged values and constants. However this both leads to worse code
and is not entirely correct assumption.
This also:
- renames various confusingly named classes: we move away from talking
about "catch entry state" to "catch entry moves" - because we only
record a subset of moves that needs to be performed and that does
not describe the whole state;
- refactors a bunch of associated code to be more readable and maintainable;
- adds documentation about catch implementation in optimized code
to runtime/docs/compiler;
Fixes https://github.com/flutter/flutter/issues/21685.
Change-Id: I03ae361a1bb7710acbd9f661ae014e663a163c59
Reviewed-on: https://dart-review.googlesource.com/74860
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Parameter types in application isolate could be modified during
execution, so it is incorrect to de-duplicate them with
read-only objects from VM isolate.
Fixes crash in pkg/front_end/tool/incremental_perf.dart
benchmark running from appjit snapshot. This crash appears after
https://dart-review.googlesource.com/c/sdk/+/45747 is applied.
Change-Id: I42a2007d02e04e0720c7e5d15224fcb6994bc515
Reviewed-on: https://dart-review.googlesource.com/45752
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Expands the mechanism that moves token streams to the VM isolate to include instructions and code metadata.
Allow the isolate snapshot to reference Instructions in the VM isolate.
R=asiva@google.com
Review-Url: https://codereview.chromium.org/2909403002 .
Ensure we still start NativeSymbolResolver even if the profiler is off, since it is also used name weak handler finalizer functions and to produce stack traces for crashes.
R=bkonyi@google.com
Review-Url: https://codereview.chromium.org/2992893002 .
Note there is no option to disable the profiler. The profiler on Mac, Linux, and Android is based on SIGPROF, and there is no way to wait for all the outstanding signals as required to be able to safely free the sample buffer.
Saves ~20MB on 64-bit VMs.
R=cbernaschina@google.com, zra@google.com
Review-Url: https://codereview.chromium.org/2989093002 .
- Adjust fingerprints to be independent of the library's private key, which varies with load order.
- Use usage_counter in AOT inlining decisions if JIT feedback is available.
- Reduce inlining in cold functions.
dart2js product aot snapshot 15841351 -> 14436273 (-8.86%)
R=fschneider@google.com
Review-Url: https://codereview.chromium.org/2562693003 .
Teagan Strickland