As part of making the compiler independent of the current isolate (since
JITed code will be shared across all isolate) we make the compiler not
depend on global field state, with one exception: we preserve an existing
optimization that utilizes knowledge whether a global final field was
already initialized (if --enable-isolate-groups is turned off) - we do
so by asking the isolate group for it's own isolate member.
Issue https://github.com/dart-lang/sdk/issues/36097
TEST=Refactoring of existing code.
Change-Id: I2f08d854af6102e05e5a1df8d5b66b514d6f3ce4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/182540
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Currently we have things called XPtr which are not what you get from ptr().
Old world:
handle->raw() returns RawObject* (tagged)
raw_obj->ptr() returns RawObject* (untagged)
After 6fe15f6df9:
handle->raw() returns ObjectPtr
obj_ptr->ptr() returns ObjectLayout*
New world:
handle->ptr() returns ObjectPtr
obj_ptr->untag() returns UntaggedObject*
TEST=ci
Change-Id: I6c7f34014cf20737607caaf84979838300d12df2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/149367
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
These checks are now performed in the dynamic closure call dispatcher.
To avoid having to create type argument vectors (TAVs) for default type
arguments at runtime, we cache a compile-time created TAV in the
ClosureData for the closure function which is retrieved by the
dispatcher when needed.
We also keep an associated packed field of information that can also be
determined at compile time:
* Whether the cached TAV needs instantiation or can share its
instantiator or function type arguments.
* The number of parent type parameters.
The former allows the generated IL to keep the invariant that the
InstantiateTypeArguments instruction (and the runtime entry it calls) is
only used for uninstantiated TAVs.
Also changes the destination name to an Value input for the
AssertSubtype instruction and adds handling for non-constant types and
names in that instruction's backend.
Additional changes:
* Adds new slots for ClosureData, Function, and TypeArguments.
* Adds a new kUnboxedUint8 representation (needed for
TypeParameterLayout::flags_, which is of type uint8_t).
* Extends LoadField to handle uint8_t unboxed native fields.
* Adds BoxUint8 for boxing unboxed uint8_t values.
Code size impact on Flutter gallery in release mode:
* arm7: total +0.08%, vmisolate: +0.56%, isolate: +0.42%,
readonly: -0.04%, instructions: -0.03%
* arm8: total +0.12%, vmisolate: +0.56%, isolate: +0.42%,
readonly: -0.002%, instructions: +0.03%
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Bug: https://github.com/dart-lang/sdk/issues/40813
Change-Id: I5a7de27a17e3119e27752bd0d10e1c6bc1b52a16
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/158844
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Régis Crelier <regis@google.com>
- Use null instead of empty array for the initial constants set, as fields dropped during snapshot are populated with null.
- Remove assumption that canonicalization will always be bottom-up. Deserialization clusters will cause canonicalization to be ordered by class instead of by depth.
Bug: https://github.com/dart-lang/sdk/issues/41974
Change-Id: Ia3ab68281c783299e682f6c60a744c320c19e981
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/165160
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Régis Crelier <regis@google.com>
This is the first step towards optimizing typed data array allocations,
which is useful for e.g. package:vector_math.
Opaque call to a typed data factory constructor is replaced with IL
instruction which doesn't have side-effects and doesn't prevent
other optimizations (e.g. load forwarding) from happening.
Asm intrinsics for typed data factories are replaced with stubs.
Issue: https://github.com/dart-lang/sdk/issues/43228
Change-Id: Icc7d4863f2f94ea5d8bb4620d041f7b6fe664098
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/161840
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Current users of InstantiateTypeArguments have the uninstantiated type
arguments available at compile time. After upcoming work on #40813,
there are cases where the generated code needs to instantiate type
arguments that are only available at runtime.
This work changes the uninstantiated type arguments for the
InstantiateTypeArguments instruction to a runtime Value pointer instead
of a compile time TypeArguments reference. The changes beyond that are
limited to only what is needed to get current uses working, with ASSERTs
checking that current invariants still hold. The rest of the changes
needed for dynamic uninstantiated type arguments will come later.
Bug: https://github.com/dart-lang/sdk/issues/40813
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Change-Id: Iafe836cfd8744d3e835e60112a4f099e631f4782
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/162183
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
This includes support for calling Dart_PropagateError in native code
when doing FFI calls, and catching uncaught exceptions with Dart_IsError
when doing FFI callbacks.
The support for Dart_PropagateError adds a catch entry to the FFI
trampoline, which prevents inlining these trampolines in AOT. This
regresses the FfiCall benchmarks by 1-2% in AOT.
In addition, Dart_PropagateError requires maintaining a bit whether we
entered native/VM code from generated code through FFI or not. That way
we can do the proper transition on the exception path. When entering
generated code, we store this bit on the stack, right after the entry
frame.
Design: http://go/dart-ffi-handles
Issue: https://github.com/dart-lang/sdk/issues/36858
Issue: https://github.com/dart-lang/sdk/issues/41319
Change-Id: Idfd7ff69132fb29cc730931a4113d914d4437396
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Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/145591
Commit-Queue: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Clean up signatures of runtime functions in object.{cc,h} using the trail to avoid cycles. Move the trail to the last parameter of these functions.
Introduce a trail in IsSubtypeOf() to avoid cycles introduced by bounds of F-bounded types. Issue uncovered by the new normalization tests.
Change-Id: I3241c7e4023a09c122e1594b7aff90b5b103f4f4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/150180
Commit-Queue: Régis Crelier <regis@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Load*Field and Init*Field IL instructions are fused into load
instructions with 'calls_initializer' flag.
A new, more powerful elimination of lazy initializer calls uses
data flow analysis and load forwarding (place numbering).
In addition to improved elimination of initializer calls,
fusing instructions avoids extra load after field is already
loaded for lazy initialization check.
Fixes https://github.com/dart-lang/sdk/issues/41417
Change-Id: Ibb2a63f84b9b0c970db67b3d6684ec15384a64e7
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/148283
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Before this change we would replace unboxed definitions (those with
representation not equal to kTagged) which is too loose and causes issues
in subsequent passes, which assume that replacements have normalised
representation.
After this change we make sure that replacement has a matching
representation.
Closes https://github.com/dart-lang/sdk/issues/35371
Fixes https://github.com/dart-lang/sdk/issues/41971
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Change-Id: I48543893562acf4f8516651196eba7c0c0769a22
Fixed: 35371,41971
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/103139
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
It might be too late to remove redundant phis in EliminateDeadPhis
because EliminateDeadPhis runs after OptimizeBranches, and
OptimizeBranches may be able to eliminate more branches if redundant
phis are cleaned up.
This change moves elimination of redundant phis into canonicalization
pass which is repeated more frequently.
Fixes recent regressions on several micro-benchmarks after
https://dart-review.googlesource.com/c/sdk/+/139314
Change-Id: Ib0148564615dbd0adb88e93b938ca9f3f59cabfd
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/148792
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Previously, AssertAssignable instructions could only be created with a
compile-time AbstractType value for dst_type. Relax this so that
AssertAssignable instructions can be created with a possibly
non-constant Value instead.
This is only an IL-level change for the instruction. Code generation for
AssertAssignable still requires the dst_type Value to be bound to a
constant and is otherwise unchanged from before, thus this should have
no impact on size or speed of generated code. (Generating the
non-constant case will be done in follow-up work.)
Bug: https://github.com/dart-lang/sdk/issues/40813
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Bug: https://github.com/dart-lang/sdk/issues/40813
Change-Id: I1f984039d8c2695c66161a69a3d80cfbe7110f19
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/146801
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
IsTopTypeForAssignability is renamed to IsTopTypeForSubtyping to better
reflect that it works both for subtyping and assignability.
Most uses of IsTopType() are changed to IsTopTypeForSubtyping().
The remaining uses of IsTopType() are checking for top types in
instance-of ('is') tests, so IsTopType is renamed to IsTopTypeForInstanceOf.
Also, Instance::IsFutureOrInstanceOf is renamed to RuntimeTypeIsSubtypeOfFutureOr
to align it with RuntimeTypeIsSubtypeOf and reflect that it is
calculating subtyping and not instance-of.
Change-Id: Ib8d3574edc1b90d80f5528330bd84b099b37d2b8
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/145446
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Régis Crelier <regis@google.com>
When using C++ value types to represent tagged pointers, we cannot use forward declarations for tagged pointers. This helps to break include cycles when attempting to keep IsXYZ predicates as tagged pointer member functions.
class_id.h also seems like a more natural place for these predicates, which were written before there was a class_id.h.
Change-Id: I0677560a794ed084d10f844606e202feb0c3820a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/144321
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Special sentinel values which are used for lazy initialization can be
stored in variables of any type. In NNBD world Null is no longer a
bottom type as null cannot be assigned into variables of non-nullable
types. The new universal bottom type is Never, so type of sentinel
values is changed from Null to Never.
This also allows to make late fields non-nullable in the type
propagation and avoid extra updates to field guards.
This change also adds special handling of comparisons with sentinel
values into constant propagation as it can constant fold comparisons
of values with different cids.
Fixes https://github.com/dart-lang/sdk/issues/40796
Change-Id: I8266cfba0cc434b78ffa9570c30d434d4380d4af
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/143864
Reviewed-by: Liam Appelbe <liama@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Given cyclic phi which participates in strict or equality comparison
with its own argument
y <- phi(x, y);
z <- y == x
CP pass would sometimes fail to converge because it would mark the phi
as unwrapped and then add it to the worklist, which would cause the
phi uses to be revisited: equality would mark the phi again and then
phi will be visited as its own use, which would add it to the worklist
because it is marked and so on.
The fix is to only add marked phis to worklist when reachability of
one of the predecessor blocks changes and that affects whether phi
can be unwrapped or not.
Test is included in a separate CL to make this fix easy to cherry pick.
Fixes https://github.com/flutter/flutter/issues/53903
Change-Id: I9e09a155d7109b7e19ba3ae5aff3fab57dc67fb8
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/143581
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
#if defined(DART_PRECOMPILED_RUNTIME)
#error "AOT runtime should not use compiler sources (including header files)"
#endif // defined(DART_PRECOMPILED_RUNTIME)
Remove #if defined(DART_PRECOMPILED_RUNTIME) from most compiler sources.
Change-Id: Id175c83fdbea38d9d5e1371ff433e3888f2afe8a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/143523
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Apply the same fix as in https://dart-review.googlesource.com/c/sdk/+/136709
to TypeArguments::CanShareInstantiatorTypeArguments and to TypeArguments::CanShareFunctionTypeArguments.
Move the inlined code performing an instantiation cache lookup to stubs in order to reduce code size.
Add stubs checking nullability of type arguments to share instantiator (or function) type arguments before looking up instantiation cache, and possibly calling into the runtime for instantiation.
Modify constant propagator to instantiate constant type arguments at compile time.
Change-Id: I72fee1a6881ac3bec55fae7d0ef5a3361544a141
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/138009
Commit-Queue: Régis Crelier <regis@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
On 1/27/20, the nnbd specification changed weak and strong mode instance checks
to make them behave uniformly across legacy and opted-in libraries.
Therefore, it is not necessary anymore to propagate the library mode in
generated code to the runtime.
Change-Id: I42d3ddc6e9a921899aeac21be6374c7893a6d27c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/138111
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Régis Crelier <regis@google.com>
Introduces NativeRepresentation and NativeLocation for the compilation of FFI.
NativeRepresentations are able to express all representations (or types) of the native ABIs we bind to with FFI, this is more representations that than that are used in Dart itself.
NativeLocations are able to express all locations of the native ABIs we bind to with FFI, this is more types of locations than that are used for the Dart calling convention.
See the documentation in the respective files.
These NativeLocations and NativeRepresentations are computed by the NativeCallingConvention and consumed by the Marshaller and Assemblers.
This reenginering is required for go/dart-ffi-by-value, hardfp (Arm S and D fpu registers), and iOS 64 bit (non-word-aligned stack arguments).
In addition, by using the NativeRepresentations we also get slightly reduced code size:
* The tracking of sizes is improved, so less sign/zero-extension operations are required.
* UnboxedWidthExtenderInstr is fully removed, the size extension is done inside the native moves, coalescing moves and size extension when possible.
* BitCastInstr is only used when really needed. This reduces code-size on arm32 softfp.
This fixes the iOS arm64 calling convention, manually tested with https://github.com/flutter/flutter/pull/46078 and https://dart-review.googlesource.com/c/sdk/+/131074.
Fixes: https://github.com/dart-lang/sdk/issues/39637
Issue: https://github.com/dart-lang/sdk/issues/36309
Issue: https://github.com/dart-lang/sdk/issues/36730
Change-Id: I8878bc0f314277bab4ca22f417c6295ecc017720
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Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/129081
Commit-Queue: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
This is a Dart-tailored implementation of the "row-displacement
dispatch table" technique for closed-world instance calls:
All interface targets in the program are grouped into selectors such
that all targets that could potentially be called from the same call
site have the same selector (currently just grouped by name).
Each selector is assigned a selector offset such that offset + classid
is unique for all selector/classid combinations where the class
implements the selector.
At every instance call site that has an interface target (i.e. where
the static type of the receiver is not dynamic), the selector offset +
receiver classid is computed and used as index into a global table of
entry points.
If the receiver can be null (as determined by the front-end TFA and the
VM type propagation), a null check is inserted before the call.
An arguments descriptor is provided (only) for selectors that need it
(those which have type parameters or optional/named parameters).
The dispatch table calls don't need the monomorphic entry code, so for
functions that are only called via dispatch table calls (i.e. never
called dynamically), the monomorphic entry code is left out.
Some future improvements to the table dispatch implementation are
mentioned in https://github.com/dart-lang/sdk/issues/40188
The table dispatch flag is disabled by default in this commit. A
separate commit enables the flag.
Change-Id: Ic2911742b4a2c9a8d3bc7df60605454cbe4c0714
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/126648
Commit-Queue: Aske Simon Christensen <askesc@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
This also fixes the implementation of 'null is T' in legacy vs opted-in library
by making it independent of strong/weak mode.
Includes updates to type propagation and call specializer.
Change-Id: I2d347ef277e08cef779faf51a972e863244ef095
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/130922
Commit-Queue: Régis Crelier <regis@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Liam Appelbe <liama@google.com>
NNBDMode does not reflect the semantics (legacy or nnbd) of type tests anymore.
Instead, the semantics are derived from the value of the strong mode flag.
This required one function to be specialized, namely the implementation of
'null is Type' in weak mode in an opted-in library, which still requires
nnbd semantics although run in weak mode.
Relevant changes are in object.h and object.cc:
- methods NNBD_NullIsInstanceOf and NNBD_IsTopType are new.
- methods IsNullType, IsTopType, and IsNeverType are modified.
Change-Id: I36cd43d93d2cfabd110cbcc6b26487a583bb089d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/130444
Commit-Queue: Régis Crelier <regis@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
This does not yet include checking of required named parameters.
Also, inlined type testing code, type testing stubs, and type propagation are
not yet updated.
Change-Id: If6d8996635474e349d28b7fd207d724838d08881
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/129922
Commit-Queue: Régis Crelier <regis@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Runtime functions do not yet implement the NNBD semantics.
In a next change, generated code will pass NNBD mode to the runtime.
Declare one new VM flags: --strong-non-nullable-type-checks
Change-Id: I050a468e4a6b665ce46c345bafba04a947cf7cb0
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/124105
Commit-Queue: Régis Crelier <regis@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
Rationale:
Previous method cached graph information (instruction and call site
counts) on a per-function level, not accounting for potential
specializations. The improved method runs an extra constant folding
pass, and only caches per-function information for non-specialized
cases. As a result, we inling much better, see for example, the
added test as illustration.
Since we no longer cache for constants, compile-time may be increased
a bit due to the extra scan. In the long run we should consider
for common constant "situations" as the call site.
https://github.com/dart-lang/sdk/issues/36880
Change-Id: I19f007c7f1860ad0ea88fafb38695dc154189ad5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/105460
Commit-Queue: Aart Bik <ajcbik@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Ryan Macnak