Instead of handling FFI related execution state and safepoint
in assembly handle it in runtime code.
The transition needs to be done before JumpToFrame unwinds
stack because unwinding destroys exit frame and this can't
be done at safepoint as GC might be traversing the stack.
An incorrect order of operation was manifesting as crashes in
GC when one isolate in a group was encountering a lot of
exceptions thrown from an FFI call and another isolate is
triggering GCs.
To catch this in the future added a bit of validation to
ExitSafepoint runtime call which triggers when --use-slow-path
is enabled. Though after refactoring this code does not
trigger this code path anymore because it was completely
removed - but it is better than nothing.
This CL also removes a lot of unnecessary complexity which
was associated with handling this transition in the stub
itself.
TEST=ffi/vmspecific_handle_test
Bug: b/408377905
Cq-Include-Trybots: dart/try:vm-aot-android-release-arm64c-try,vm-aot-android-release-arm_x64-try,vm-aot-asan-linux-release-x64-try,vm-aot-linux-debug-x64-try,vm-aot-linux-debug-x64c-try,vm-aot-mac-release-arm64-try,vm-aot-msan-linux-release-x64-try,vm-aot-obfuscate-linux-release-x64-try,vm-aot-optimization-level-linux-release-x64-try,vm-aot-tsan-linux-release-x64-try,vm-aot-ubsan-linux-release-x64-try,vm-aot-win-debug-x64-try,vm-aot-win-debug-x64c-try,vm-appjit-linux-debug-x64-try,vm-asan-linux-release-arm64-try,vm-asan-linux-release-x64-try,vm-checked-mac-release-arm64-try,vm-eager-optimization-linux-release-ia32-try,vm-eager-optimization-linux-release-x64-try,vm-ffi-android-debug-arm-try,vm-ffi-android-debug-arm64c-try,vm-ffi-mac-debug-simarm64_arm64-try,vm-ffi-qemu-linux-release-arm-try,vm-ffi-qemu-linux-release-riscv64-try,vm-fuchsia-release-x64-try,vm-linux-debug-ia32-try,vm-linux-debug-x64-try,vm-linux-debug-x64c-try,vm-mac-debug-arm64-try,vm-mac-debug-x64-try,vm-msan-linux-release-arm64-try,vm-msan-linux-release-x64-try,vm-reload-linux-debug-x64-try,vm-reload-rollback-linux-debug-x64-try,vm-tsan-linux-release-arm64-try,vm-tsan-linux-release-x64-try,vm-ubsan-linux-release-arm64-try,vm-ubsan-linux-release-x64-try,vm-win-debug-x64-try,vm-win-debug-x64c-try,vm-win-release-ia32-try
Change-Id: Ia073cb6bb9e1b5a0ea8514c7e048cee6019b84d6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/420324
Commit-Queue: Slava Egorov <vegorov@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
The transitions in C++ have asserts which run in debug mode to validate
that the transitions are happening in the right order.
The transitions in the generated code had no equivalent. This CL
introduces the equivalent for the generated code.
The transitions to generated code are misnamed currently. They come
from either VM or Native, not only Native. For example the FFI
callbacks and call return sequence can already transition from native
into the VM when entering the safepoint.
These checks don't catch the invalid FFI callbacks.
Bug: https://github.com/dart-lang/sdk/issues/60021
These are caught when looking up the FFI metadata:
https://dart-review.googlesource.com/c/sdk/+/407023
This CL omits to implement the check in ia32, since ia32 is scheduled
for removal.
The check is only enabled in debug mode. The asserts for the C++ are
also only run in debug mode. And enabling this check in release for
AOT regresses the parent CL benchmark by ~30% on Mac Arm64.
TEST=test/ffi
Change-Id: Ieaf1e43533baae294af37b2e171b68bd314fdbe0
Cq-Include-Trybots: dart/try:vm-aot-android-release-arm64c-try,vm-aot-android-release-arm_x64-try,vm-aot-asan-linux-release-x64-try,vm-aot-linux-debug-x64-try,vm-aot-linux-debug-x64c-try,vm-aot-mac-release-arm64-try,vm-aot-mac-release-x64-try,vm-aot-msan-linux-release-x64-try,vm-aot-obfuscate-linux-release-x64-try,vm-aot-optimization-level-linux-release-x64-try,vm-aot-tsan-linux-release-x64-try,vm-aot-ubsan-linux-release-x64-try,vm-aot-win-debug-arm64-try,vm-aot-win-debug-x64-try,vm-aot-win-debug-x64c-try,vm-appjit-linux-debug-x64-try,vm-asan-linux-release-arm64-try,vm-asan-linux-release-x64-try,vm-checked-mac-release-arm64-try,vm-ffi-android-debug-arm-try,vm-ffi-android-debug-arm64c-try,vm-ffi-qemu-linux-release-arm-try,vm-ffi-qemu-linux-release-riscv64-try,vm-fuchsia-release-arm64-try,vm-fuchsia-release-x64-try,vm-linux-debug-ia32-try,vm-linux-debug-x64-try,vm-linux-debug-x64c-try,vm-mac-debug-arm64-try,vm-mac-debug-x64-try,vm-msan-linux-release-arm64-try,vm-msan-linux-release-x64-try,vm-reload-linux-debug-x64-try,vm-reload-rollback-linux-debug-x64-try,vm-tsan-linux-release-arm64-try,vm-tsan-linux-release-x64-try,vm-ubsan-linux-release-arm64-try,vm-ubsan-linux-release-x64-try,vm-win-debug-arm64-try,vm-win-debug-x64-try,vm-win-debug-x64c-try,vm-win-release-ia32-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/407021
Reviewed-by: Liam Appelbe <liama@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
On architectures with a weak memory model, there is the possibility that the concurrent marker can see the publishing store of a new object before it sees the initializing store of that object's header. On an M1, the barrier to prevent reordering these stores is fairly cheap, so we emit this barrier on Mac/iOS ARM64. Otherwise, this barrier is very expensive (or at least expensive for some hardware within the ABI), so instead we avoid the race by deferring marking of objects inside an active TLAB.
Disable TSAN instrumentation on the marker setting the mark bit, as TSAN does not understand fences.
TEST=ooo arm64 machines
Bug: https://github.com/dart-lang/sdk/issues/56845
Change-Id: I0676661a7cf941fdc6b451e516d890c26826bb3b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/389265
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
For non-x86 architectures, these forms directly translate to a
single instruction when possible. On x86 architectures,
XImmediate(dst, src, imm) where X is in {Lsl, ArithmeticShiftRight, And}
can be translated to:
MoveRegister(dst, src);
XImmediate(dst, imm);
in the general case since MoveRegister(dst, src) is a no-op if dst and
src are the same.
Also add versions of these assembler macros that take an OperandSize
and handle 32-bit OperandSizes appropriately on 64-bit architectures.
Ensure the implementation for LslImmediate and
ArithmeticShiftRightImmediate emits no instructions if shift == 0,
dst == src, and OperandSizeInBits(sz) == kBitsPerWord on all
architectures.
-----
Other changes:
Fix ConstantExpression::EmitMoveToLocation on ARM64 to match
other architectures, which allow any word-sized or less unboxed
integer representation.
Fill out ExtendValue on RISCV for previously unimplemented
OperandSizes, using the Zba and Zbb extensions when possible.
-----
TEST=vm/cc/Assembler_AndImmediate vm/cc/Assembler_LslImmediate
vm/cc/Assembler_ArithmeticShiftRightImmediate
Separated out of https://dart-review.googlesource.com/c/sdk/+/378706
for easier debugging/reviewing.
Change-Id: I721f1334784f7011a958ea8af29f0e56c620726c
Cq-Include-Trybots: luci.dart.try:vm-aot-linux-release-simarm_x64-try,vm-aot-linux-debug-x64-try,vm-aot-mac-release-arm64-try,vm-aot-mac-product-arm64-try,vm-aot-linux-product-x64-try,vm-aot-dwarf-linux-product-x64-try,vm-aot-linux-debug-simarm_x64-try,vm-linux-debug-x64-try,vm-mac-debug-arm64-try,vm-mac-release-arm64-try,vm-linux-debug-ia32-try,vm-aot-android-release-arm64c-try,vm-ffi-android-debug-arm64c-try,vm-aot-linux-debug-x64c-try,vm-linux-debug-x64c-try,vm-ffi-qemu-linux-release-arm-try,vm-ffi-qemu-linux-release-riscv64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/386180
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
Decorating a field with 'vm:shared' pragma makes values in this field accessible to all isolates in an isolate group.
Introduce `channel` to the `Version` class so that the pragma can only be enabled on main and dev channels.
TEST=shared_test, shared_fail_without_flag_test
BUG=https://github.com/dart-lang/sdk/issues/55991
Change-Id: I843c9f0d2ffc9f2ced7ddc4006bb6f9ca4e2ddf4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/370064
Reviewed-by: Slava Egorov <vegorov@google.com>
Commit-Queue: Alexander Aprelev <aam@google.com>
Add an additional base argument to Assembler::AddScaled so it now
computes:
dest <- base + (index << scale) + offset
If base is kNoRegister (or ZR when available), then it emits
instructions optimized for computing:
dest <- (index << scale) + offset
(i.e., its previous implementation)
Add AddScaled to AssemblerBase to ensure the same interface across all
architectures.
Rework the backend of CalculateElementAddress to use AddScaled
appropriately, which unifies it across architectures.
TEST=ci (refactoring)
Cq-Include-Trybots: luci.dart.try:vm-aot-linux-debug-simarm_x64-try,vm-aot-linux-debug-simriscv64-try,vm-aot-linux-debug-x64-try,vm-aot-linux-debug-x64c-try,vm-linux-debug-ia32-try,vm-linux-debug-x64-try,vm-linux-debug-x64c-try,vm-linux-debug-simriscv64-try,vm-mac-debug-arm64-try,vm-aot-mac-release-arm64-try
Change-Id: I33c8f99604b68360f10b79050bd66ceb9d65ac9b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/370504
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Delay changing Thread::vm_tag on callback entry and restore the tag early on callback return so that the profiler doesn't see the "running Dart" tag unless it can also see the fake return address marking the entry frame.
TEST=ffi/async_void_function_callbacks, ffi/function_callbacks_subtype, ffi/function_callbacks, ffi/isolate_local_function_callbacks
Bug: https://github.com/dart-lang/sdk/issues/52814
Change-Id: I40d80ec7c44063d078db0e211565e2d127c6b81e
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/367460
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
When uploading CLs, the presubmit checks verify that the lines in the
diff are formatted correctly according to `git cl format runtime`.
However, when `buildtools/<os>-<arch>/clang/bin/clang-format` is
updated, it does not force reformatting of files that would be
reformatted.
This leads to two issues:
* Inconsistent style within the code base and within a single file.
* Spurious reformatting in CLs when (1) clang-format is used on the
whole file, or (2) the diff lines overlap.
`clang-format` doesn't change that frequently, so in general this is
not a large issue, but I've seen a bit too many "spurious formatting,
please revert" comments on CLs recently.
This CL formats the runtime to be in line with the current pinned
`clang-format`:
```
$ find runtime/ -iname *.h -o -iname *.cc | xargs buildtools/mac-arm64/clang/bin/clang-format -i
```
`git cl format` (which only formats changed lines, and does so with
`clang-format`) seems to not agree with itself, or clang-format, or
cpplint in a handful of places. This CL adds `// clang-format off`
for these. (See previous patchsets for the specific instances.)
TEST=A variety of bots including GCC, MacOS and Windows.
Change-Id: I470892e898971899fda14bb3b8f2c8efefd67686
Cq-Include-Trybots: luci.dart.try:vm-gcc-linux-try,vm-ffi-qemu-linux-release-riscv64-try,vm-ffi-qemu-linux-release-arm-try,vm-aot-win-debug-x64-try,vm-win-debug-x64c-try,vm-mac-debug-x64-try,vm-mac-debug-arm64-try,vm-aot-linux-debug-x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/362780
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Daco Harkes <dacoharkes@google.com>
Add OperandSize arguments to the non-compressed Store methods so that
the compressed Store methods can be implemented as calls to the
corresponding non-compressed method using kObjectBytes. This makes it
so that all compressed Store methods are now non-virtual.
Add a scratch register argument to all Store methods that involve a
write barrier that defaults to TMP. Originally only the IA32
implementation took a scratch register, with the others using TMP or
TMP2 internally.
Since all architectures can represent a register/offset pair as an
Address without losing information, make all the offset-based load
and store methods have an implementation that creates an Address or
FieldAddress and calls the corresponding address-based store method.
This makes all the offset-based load and store methods non-virtual.
After this, most of the Store methods are non-virtual, with
only the base methods used to implement them as virtual:
* Store
* StoreRelease
* StoreObjectIntoObjectNoBarrier
* StoreBarrier
* ArrayStoreBarrier
* VerifyStoreNeedsNoWriteBarrier (for DEBUG use only)
The Load methods can't be consolidated quite so much, as the
base methods for handling non-Smi compressed pointers must be defined
per-architecture, as each compressed pointer architecture handles
adding the upper bits for the heap separately.
Have LoadFieldInstr::EmitNativeCode use Assembler::LoadToSlot when the
result location is a single integer register and
StoreFieldInstr::EmitNativeCode use Assembler::StoreToSlot and
Assembler::StoreToSlotNoBarrier when the value location is a single
integer register to avoid code duplication between those methods.
Handle both compressed and uncompressed Smi fields in LoadFromSlot.
TEST=ci (refactoring)
Cq-Include-Trybots: luci.dart.try:vm-aot-android-release-arm64c-try,vm-aot-linux-debug-x64-try,vm-aot-linux-debug-x64c-try,vm-aot-mac-release-arm64-try,vm-aot-mac-release-x64-try,vm-aot-obfuscate-linux-release-x64-try,vm-aot-optimization-level-linux-release-x64-try,vm-aot-win-debug-arm64-try,vm-appjit-linux-debug-x64-try,vm-asan-linux-release-x64-try,vm-checked-mac-release-arm64-try,vm-eager-optimization-linux-release-ia32-try,vm-eager-optimization-linux-release-x64-try,vm-ffi-android-debug-arm-try,vm-ffi-android-debug-arm64c-try,vm-ffi-qemu-linux-release-arm-try,vm-ffi-qemu-linux-release-riscv64-try,vm-linux-debug-ia32-try,vm-linux-debug-x64c-try,vm-mac-debug-arm64-try,vm-mac-debug-x64-try,vm-msan-linux-release-x64-try,vm-reload-linux-debug-x64-try,vm-reload-rollback-linux-debug-x64-try,vm-ubsan-linux-release-x64-try,vm-win-debug-x64-try,vm-win-release-ia32-try
Change-Id: I60cc03776af220ed87918664bb4b9abafff2788a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/360641
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Remove CompareWithCompressedFieldFromOffset, which has no uses.
Rename the LoadFromOffset and StoreFromOffset methods that took
Addresses to Load and Store, respectively. This makes the names
of the Assembler methods more uniform:
* Takes an address: Load, Store, LoadField, LoadCompressedField,
StoreIntoObject, StoreCompressedIntoObject, LoadSmi,
LoadCompressedSmi, etc.
* Takes a base register and an offset: LoadFromOffset, StoreToOffset,
LoadFieldFromOffset, LoadCompressedFieldFromOffset,
StoreIntoObjectOffset, StoreCompressedIntoObjectOffset,
LoadSmiFromOffset, LoadCompressedSmiFromOffset, etc.
Create AssemblerBase methods for loading and storing compressed
pointers that weren't already there, as well as the corresponding
methods for loading and storing uncompressed values.
Make non-virtual methods that load and store uncompressed fields
that call the corresponding method for loading from and storing to
memory regions, adjusting the address or offset accordingly. This
avoids needing per-architecture overrides for these.
Make non-virtual methods that load compressed fields, calling the
corresponding method for loading a compressed value from a memory
region. (Since compressed pointers are only stored in Dart objects,
and stores into a Dart object may require a barrier, there is no
method for storing a compressed value into an arbitrary memory region.)
Create pure virtual methods for loading from or storing to an Address
or any method that does not have both an Address-taking and a
base register and offset pair-taking version (e.g., LoadAcquire).
Create methods for loading from or storing to a base register
and an offset. The base implementation takes the base register and
offset and creates an Address from it, then calls the Address-taking
equivalent. These methods are non-virtual when the implementation is
the same on all architectures and virtual to allow overriding when
necessary.
Make a non-virtual method for loading uncompressed Smis, since all
architectures have the same code for this, including the DEBUG check.
If compressed pointers are not being used, all the methods for
compressed pointers are non-virtual methods that call the
corresponding method for uncompressed values.
If compressed pointers are being used:
* Install pure virtual methods for loading compressed values from
and storing compressed values to an Address or any method that does
not have both an Address-taking and a base register and offset
pair-taking version (e.g., LoadAcquireCompressed).
* Install virtual methods for loading compressed values from and
storing compressed values to a base register and offset. Like the
uncompressed implementation, the base implementation of these
create an Address and call the Address-taking equivalent, and these
implementations are overridden on ARM64.
* Install a non-virtual method for loading compressed Smis, since the
only difference is that it loads a zero-extended 32-bit value, which
AssemblerBase can do.
TEST=ci (refactoring only)
Change-Id: I934791d26a6e2cdaa6ac5f188b0fd89dbdc491d1
Cq-Include-Trybots: luci.dart.try:vm-aot-android-release-arm64c-try,vm-aot-android-release-arm_x64-try,vm-aot-linux-debug-x64-try,vm-aot-linux-debug-x64c-try,vm-aot-mac-release-arm64-try,vm-aot-mac-release-x64-try,vm-aot-obfuscate-linux-release-x64-try,vm-aot-optimization-level-linux-release-x64-try,vm-aot-win-debug-arm64-try,vm-appjit-linux-debug-x64-try,vm-asan-linux-release-x64-try,vm-checked-mac-release-arm64-try,vm-eager-optimization-linux-release-ia32-try,vm-eager-optimization-linux-release-x64-try,vm-ffi-android-debug-arm-try,vm-ffi-android-debug-arm64c-try,vm-ffi-qemu-linux-release-arm-try,vm-ffi-qemu-linux-release-riscv64-try,vm-linux-debug-ia32-try,vm-linux-debug-x64c-try,vm-mac-debug-arm64-try,vm-mac-debug-x64-try,vm-msan-linux-release-x64-try,vm-reload-linux-debug-x64-try,vm-reload-rollback-linux-debug-x64-try,vm-ubsan-linux-release-x64-try,vm-win-debug-arm64-try,vm-win-debug-x64-try,vm-win-release-ia32-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/359861
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
The refactoring in https://dart-review.googlesource.com/c/sdk/+/345002
erroneously assumed that if the caller to
Assembler::AddressCanHoldConstantIndex didn't pass an out parameter to
detect whether a base register was needed, that that case shouldn't be
considered.
While it's true that LoadIndexedInstr::MakeLocationSummary originally
ignored the value stored in the out parameter, it did that because it
can use TMP to store the array base, unlike the code for
StoreIndexedInstr which must have a temporary register allocated during
register allocation.
Thus, fix Assembler::AddressCanHoldConstantIndex to always require
the out parameter, and add a comment in LoadIndexedInstr as to why
we ignore the out parameter in this case instead of allocating an
additional temporary register.
TEST=vm/cc/Assembler_Regress54621
Fixes: https://github.com/dart-lang/sdk/issues/54621
Change-Id: I0af557565faf657a87641457884334446e9b7cc5
Cq-Include-Trybots: luci.dart.try:vm-ffi-qemu-linux-release-arm-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/346201
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
Previously, CanBeImmediateIndex calculated the scaling factor for the
index using Instance::ElementSizeFor. However, the LoadIndexed and
StoreIndexed instructions which use this function have an index_scale_
field that is not necessarily the same as the element size for the
class id. This means the displacement calculated within
CanBeImmediateIndex can differ from the actual displacement calculated
within ElementAddressForIntIndex, causing the bug seen by the fuzzer.
This CL moves the check in CanBeImmediateIndex to a new static
method Assembler::AddressCanHoldConstantIndex. In addition to the
original arguments to CanBeImmediateIndex, the new static method takes
an index_scale argument, so the field value can be passed appropriately.
It also adds an is_external argument on X64 and IA32 to match the other
architectures, since assuming a non-external typed data object could
cause a register to be used in cases where it isn't necessary.
TEST=vm/dart/regress_54486
Fixes: https://github.com/dart-lang/sdk/issues/54486
Change-Id: Ia553fb7da0500113b35f8d9af91a52df55437a3c
Cq-Include-Trybots: luci.dart.try:vm-aot-linux-debug-x64-try,vm-linux-debug-ia32-try,vm-aot-linux-debug-simarm_x64-try,vm-aot-linux-debug-simriscv64-try,vm-aot-mac-release-arm64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/345002
Reviewed-by: Daco Harkes <dacoharkes@google.com>
When generating code for deferred units compiler
can't emit PC relative call to the shared Mint allocation
stub. This causes compiler to emit an indirect call
through a Code object. Such calls clobber CODE_REG
which is actually an allocatable register.
Fix this by using non-allocatable register instead of
CODE_REG when generating indirect calls through
Code object in AOT mode. Callees don't expect
anything useful in CODE_REG anyway because AOT
calling convetion does not use it.
TEST=vm/cc/{BranchLinkPreservesRegisters,JumpAndLinkPreservesRegisters,CallCodePreservesRegisters}
Bug: b/242559057
Cq-Include-Trybots: luci.dart.try:vm-aot-linux-release-arm64-try,vm-aot-linux-release-simarm_x64-try,vm-aot-linux-release-x64-try,vm-aot-linux-product-x64-try,vm-aot-obfuscate-linux-release-x64-try,vm-aot-optimization-level-linux-release-x64-try,vm-aot-linux-debug-simriscv64-try,vm-ffi-qemu-linux-release-riscv64-try
Change-Id: Ib1fdc1c104d0269d41bb1ab9cbe292ad28c7cd49
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/338127
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Slava Egorov <vegorov@google.com>
Adds a `CachableIdempotentCallInstr` that can be invoked via
`@pragma('vm:cachable-idempotent')` if the call-sites is force
optimized.
The object pool is not visited by the scavenger. So, we store the
results as unboxed integers. Consequently, only dart functions that
return integers can be cached.
Cachable idempotent calls should never be inlined. After the first
call the function not be called again.
The call itself is on a slow path to avoid register spilling on the
fast path.
TEST=vm/cc/IRTest_CachableIdempotentCall
TEST=runtime/tests/vm/dart/cachable_idempotent_test.dart
Bug: https://github.com/dart-lang/sdk/issues/51618
Change-Id: I612e896f27add76f57796c060157e14cc687a0fd
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Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/301601
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Follow up of:
* https://dart-review.googlesource.com/c/sdk/+/328861
* https://dart-review.googlesource.com/c/sdk/+/331087
* https://dart-review.googlesource.com/c/sdk/+/331120
The pool entries for switchable calls have their pool entries
transformed during snapshot loading in AOT. This behavior is now folded
into `SnapshotBehavior`.
Because snapshot behavior is set on the call sites, and the call sites
are already AOT specific, no conditionals inside app_snapshot.cc are
needed anymore.
The Arm64 implementation does not use the assembler for implicitly
adding pool entries, it does so explictly and loads two pool entries
in one load.
We could consider doing these explicit loads in the other architectures
as well. This would avoid adding the snapshot_behavior argument to
`LoadUnqiueObject` for the other architectures.
IA32 has no AOT support.
TEST=precomp bots
Change-Id: I75f70e00ca44f6545694d9b59e3ad08ad8bb3f8e
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Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/331101
Commit-Queue: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
`NativeCallInstr::EmitNativeCode` `link_lazily` code path uses the
new snapshotting behavior, and the non-`link_lazily` checks that it's
never snapshotted.
The snapshot behavior argument is threaded from the the EmitNativeCode
to the places where the pool entry is constructed.
Does not yet migrate `kSwitchableCallMissEntryPoint` and
`kMegamorphicCallEntryPoint`.
TEST=CI
Change-Id: I8dd1dc5aa525f888b493856c60ae385087463d02
Cq-Include-Trybots: luci.dart.try:vm-ffi-qemu-linux-release-riscv64-try,vm-linux-debug-simriscv64-try,vm-aot-linux-release-arm64-try,vm-aot-android-release-arm64c-try,vm-aot-win-debug-arm64-try,vm-aot-mac-product-arm64-try,vm-mac-debug-arm64-try,vm-ffi-android-debug-arm-try,vm-ffi-qemu-linux-release-arm-try,vm-linux-debug-ia32-try,vm-linux-debug-x64-try,vm-aot-linux-debug-x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/328861
Commit-Queue: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
When copying elements that are smaller than words on non-X86
architectures, only copy element by element until the remaining elements
can be copied in word-sized chunks, and then do so.
TEST=vm/cc/IRTest_Memory, co19{,_2}/LibTest/typed_data,
lib{,_2}/typed_data, corelib{,_2}/list_test
Issue: https://github.com/dart-lang/sdk/issues/42072
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Change-Id: I61eab310b92a6bc5ebd88fa63d562103d887cb74
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/324280
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Also eliminates the need to store the delayed type arguments on the
stack during the search loop on ARM.
TEST=vm/cc/TTS
Change-Id: Ife01cc8d255724c272bc277eec397486cedc07a7
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Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/307681
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
In d592882f, the old uint8_t `type_state_` and `nullability_` fields
in subclasses of `AbstractType` were merged into a single uint32_t
`flags_` field in `AbstractType` itself.
Accessing the nullability information was abstracted into two methods:
* `LoadAbstractTypeNullability`
* `CompareAbstractTypeNullabilityWith`
However, the code from these methods were based off the old
`CompareTypeNullabilityWith` and `CompareFunctionTypeNullabilityWith`
methods that used unsigned byte loads to access the old field, and kept
that even though the new field is now a 32-bit unsigned integer. This
works for now, because the nullability portion of the `flags_` field
happens to be the lowest two bits, but might lead to confusion if
someone attempts to write similar code for accessing the other parts of
the `flags_` field without realizing it's larger than 8 bits.
Thus, this CL does the following:
* Unifies the implementation of both methods across architectures.
* Adds a native slot definition for the `AbstractType::flags_` field
and uses `LoadFromSlot` to load the `flags_` field instead. Other
places where the `AbstractType::flags_` field is accessed from the
assembler are also changed to use `LoadFromSlot` appropriately.
TEST=The existing suite of tests are sufficient.
Change-Id: Ie578e4dddce810223ca9e767403136cb40d340f3
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Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/302187
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
The representation of record shape in record instances and record
types is changed from a pair
int num_fields
Array field_names
to a single integer - packed bitfield
int num_fields(16)
int field_names_index(kSmiBits-16)
where field names index is an index in the array available from
ObjectStore.
With the new representation of record shapes:
1) Size of record instances is reduced.
2) Number of comparisons for a shape test reduced from 2 to 1
(shape test is used during type checks).
3) A few operations removed from Record.hashCode.
4) Type testing stubs (TTS) are now supported for record types with
named fields. Previously it was not possible to check shape of records
with named fields in TTS as TTS cannot access object pool and cannot
load field names array).
TEST=existing
Issue: https://github.com/dart-lang/sdk/issues/49719
Change-Id: I7cdcbb53938aba5d561cd24dc99530395dbbea7e
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/276201
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
AsmIntrinsifier::OneByteString_getHashCode now uses the CombineHashes
and FinalizeHash Assembler methods introduced in 49f998dc31.
To avoid having to check for 0 again after masking the result of
FinalizeHash to fit the desired bit size, we create a more general
FinalizeHashForSize that also takes the desired bit size of the result.
The intrinsified versions for ARM/ARM64/RISCV are also modified to
remove the special casing for the empty string, and instead just check
the size of the string against the loop counter at the start of the
loop, similarly to X64/IA32. This is less efficient for the empty
string case, but avoids the need to create a version of FinalizeHash
that elides the zero check.
TEST=ci
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Change-Id: I53db731acb8bf35d16efb55fa2c5a79d8302399f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/272800
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
Lower the threshold for converting from a linear to a hash-based cache
on most architectures from 500 to 10.
Due to register pressure, the InstantiateTypeArguments stub on IA32
continues to go to the runtime for hash caches, and so we do not
lower the threshold for converting to a hash-based cache there.
The following are benchmark results for those benchmark that use enough
Instantiations to trigger the use of hash-based caches. In the following
tables, "Results 1" denotes the benchmark results from only this change,
whereas "Results 2" include from comparing to the results prior to
4f925105cf, when only linear caches were used.
Dart AOT:
* InstantiateTypeArguments.Instantiate100
Arch | CPU | Results 1 | Results 2
-------|----------------|-----------------------
ARM | Odroid-C2 | 382.8% | 381.5%
ARM | Raspberry Pi 4 | 486.7% | 449.2%
ARM64 | Odroid-C2 | 328.1% | 372.8%
ARM64 | Raspberry Pi 4 | 1283% | 1281%
ARM64C | Raspberry Pi 4 | 2353% | 2811%
X64 | Intel Xeon | 568.7% | 584.9%
* InstantiateTypeArguments.Instantiate1000
Arch | CPU | Results 1 | Results 2
-------|----------------|------------------------
ARM | Odroid-C2 | 743.7% | 3821%
ARM | Raspberry Pi 4 | 486.7% | 3218%
ARM64 | Odroid-C2 | 584.7% | 3222%
ARM64 | Raspberry Pi 4 | 430.7% | 8172%
ARM64C | Raspberry Pi 4 | 491.4% | 16699%
X64 | Intel Xeon | 954.1% | 5528%
Dart JIT:
* InstantiateTypeArguments.Instantiate100
Arch | CPU | Results 1 | Results 2
-------|----------------|-----------------------
ARM | Raspberry Pi 4 | 315.7% | 295.1%
ARM64 | Raspberry Pi 4 | 1070% | 1058%
ARM64C | Raspberry Pi 4 | 1769% | 2095%
X64 | Intel Xeon | 507.4% | 496.2%
* InstantiateTypeArguments.Instantiate1000
Arch | CPU | Results 1 | Results 2
-------|----------------|-----------------------
ARM | Raspberry Pi 4 | 565.2% | 2550%
ARM64 | Raspberry Pi 4 | 406.8% | 7375%
ARM64C | Raspberry Pi 4 | 379.6% | 12996%
X64 | Intel Xeon | 807.9% | 4459%
During work on this change, an issue was found where cache lookups
in the stub on ARM64C always failed and went to runtime, even with
the old linear-only caches, hence the much larger performance gains
in those rows above.
TEST=vm/cc/TypeArguments_Cache_{Some,Many}Instantiations
Fixes: https://github.com/dart-lang/sdk/issues/48344
Change-Id: I3d29566ba0582502954c9fc59626ceb8fd40317a
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-dwarf-linux-product-x64-try,vm-kernel-precomp-linux-product-x64-try,vm-kernel-precomp-linux-release-x64-try,vm-kernel-precomp-nnbd-mac-release-arm64-try,vm-kernel-precomp-nnbd-linux-release-simarm_x64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-nnbd-linux-release-x64-try,vm-kernel-precomp-nnbd-linux-release-simarm64-try,vm-kernel-precomp-nnbd-linux-debug-simriscv64-try,vm-kernel-precomp-tsan-linux-release-x64-try,vm-kernel-tsan-linux-release-x64-try,vm-kernel-precomp-linux-debug-x64c-try,vm-kernel-nnbd-linux-debug-simriscv64-try,vm-kernel-linux-release-simarm-try,vm-kernel-linux-release-simarm64-try,vm-kernel-linux-release-ia32-try,vm-kernel-nnbd-linux-release-simarm-try,vm-kernel-nnbd-linux-release-simarm64-try,vm-kernel-nnbd-linux-release-ia32-try,vm-kernel-nnbd-mac-release-arm64-try,vm-kernel-linux-debug-x64c-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/270702
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Some large applications are bumping up against the 16-bit limit.
The object header changes from hash:32,cid:16,size:8,gc:8 to hash:32,cid:20,size:4,gc:8.
Because the CID field is no longer a power of two, it takes two instructions to load instead of one, increasing code size. The alternative change to cid:32,hash:24,gc:8 was considered and rejected because the reduction in hash bits very noticeably affects performance in applications with large data sets.
TEST=ci
Bug: b/255934984
Change-Id: I5fa36ba48a6852359d994393cf80c6a761c5d84c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/269120
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Moves `RangeCheck` from the intrinsifier to the assembler.
Also, unifies the signature and semantics and adds documentation.
TEST=refactor
Change-Id: I274e5e46fde6a6e8baf30d8b732932f4f46d5855
Cq-Include-Trybots: luci.dart.try:vm-kernel-linux-debug-simriscv64-try,vm-kernel-precomp-linux-debug-simriscv64-try,vm-kernel-linux-release-simarm64-try,vm-kernel-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-linux-release-simarm-try,vm-precomp-ffi-qemu-linux-release-riscv64-try,vm-precomp-ffi-qemu-linux-release-arm-try,vm-kernel-linux-debug-ia32-try,vm-kernel-linux-debug-x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/261681
Reviewed-by: Tess Strickland <sstrickl@google.com>
Commit-Queue: Daco Harkes <dacoharkes@google.com>
Instead apply the same approach as we do in AOT: unbox based on the
static type information. There are no TFA results available in JIT,
but we could still unbox fields when running in sound null-safety.
TEST=ci
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Change-Id: Ide2e78c6659261ef8d245a4586cf699ea0fbb459
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/256211
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Slava Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
* Merge ClassTable and SharedClassTable back together;
* Simplify handling of multiple arrays growing in sync;
* Refactor how reload deals with ClassTable.
The last change is the most important because it makes it
much easier to reason about the code. We move away from
copying bits and pieces of the class table and shared
class table into reload contexts.
Having two class table fields in the isolate group makes
it easier to reason about. One field contains program
class table (one modified by kernel loader and accessed
by various program structure cid lookups) and heap
walk class table (used by GC visitors). Normally these
two fields point to the same class table, but during
hot reload we temporary split them apart: original
class table is kept as a heap walk class table, while
program class table is replaced by a clone and updated
by reload.
If reload succeeds we drop original class table and
set program class table as heap walk one.
If reload fails we drop the program class table and
restore original one from heap walk table.
TEST=ci
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Change-Id: I8b66259fcc474dea7dd2af063e4772df99be06c4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/258361
Commit-Queue: Slava Egorov <vegorov@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
The new implementation is based on suspend/resume stubs and doesn't
use desugaring of async functions on kernel AST.
Previously, new implementation of async/async* was only supported in
AOT mode. This change adds all necessary bits for the JIT mode:
* Suspending variable-length frames (for unoptimized code).
* Handling of Code and pool pointers in Dart stack frames.
* OSR.
* Deoptimization.
* Hot reload.
* Debugger.
The new implementation is not enabled in JIT mode yet.
Design doc: go/compact-async-await.
TEST=ci
Issue: https://github.com/dart-lang/sdk/issues/48378
Change-Id: I477d6684bdce7cbc1edb179ae2271ff598b7dcc5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/246081
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Johnni Winther <johnniwinther@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
The CCallInstr takes unboxed word-sized integers and does a call to C
without any VM transitions.
This can be used for the following.
1) Leaf runtime entries. This CL removes the EnterHandleScope,
ExitHandleScope, and AllocateHandle instructions.
2) Compilation of isolate independent code where all definitions in IL
are unboxed integers.
Currently, the CCallInstr expects all it's arguments and the return type
to be word-sized.
This CL also:
- Adds loadImmediate and CCall with a register for each assembler.
- Adds a CSE pass to force-optimized so that LoadThreadInstr gets de-
duplicated.
TEST=tests/ffi(_2)/*
Change-Id: I67c6aaa1b7d6aa7d60e274477686a54e5a331216
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Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/246240
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
(Macro-)assembler helper PushRegistersInOrder generates series of
register pushes in an architecture-specific way:
* Using STMDB on ARM (if possible).
* Using STP on ARM64.
* Updating SP only once on RISC-V.
TEST=ci
Change-Id: I6cbd1dd5f8acf8ce8087ed899a311264a873ad37
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/243100
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
The new implementation moves away from desugaring of async
functions on kernel AST, state machine generated in the flow graph and
capturing all local variables in the context.
Instead, async/await is implemented using a few stubs
(InitSuspendableFunction, Suspend, Resume, Return and
AsyncExceptionHandler). The stubs are implemented in a
platform-independent way using (macro-)assembler helpers.
When suspending a function, its frame is copied into a SuspendState
object, and when resuming a function it is copied back onto the stack.
No extra code is generated for accessing local variables.
Callback closures are created lazily on the first await.
Design doc: go/compact-async-await.
Part 1 (kernel): https://dart-review.googlesource.com/c/sdk/+/241842
TEST=ci
Issue: https://github.com/dart-lang/sdk/issues/48378
Change-Id: Ibad757035b7cc438ebdff80b460728b1d3eff1f5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/242000
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
Vyacheslav Egorov