Relands 165c583d57
[VM] Introduction of type testing stubs - Part 1
This CL:
* Adds a field to [RawAbstractType] which will always hold a pointer
to the entrypoint of a type testing stub
* Makes this new field be initialized to a default stub whenever a
instances are created (e.g. via Type::New(), snapshot reader, ...)
* Makes the clustered snapshotter write a reference to the
corresponding [RawInstructions] object when writing the field and do
the reverse when reading it.
* Makes us call the type testing stub for performing assert-assignable
checks.
To reduce unnecessary loads on callsites, we store the entrypoint of the
type testing stubs directly in the type objects. This means that the
caller of type testing stubs can simply branch there without populating
a code object first. This also means that the type testing stubs
themselves have no access to a pool and we therefore also don't hold on
to the [Code] object, only the [Instruction] object is necessary.
The type testing stubs do not setup a frame themselves and also have no
safepoint. In the case when the type testing stubs could not determine
a positive answer they will tail-call a general-purpose stub.
The general-purpose stub sets up a stub frame, tries to consult a
[SubtypeTestCache] and bails out to runtime if this was unsuccessful.
This CL is just the the first, for ease of reviewing. The actual
type-specialized type testing stubs will be generated in later CLs.
Reviewed-on: https://dart-review.googlesource.com/44787
Relands f226c22424
[VM] Introduction of type testing stubs - Part 2
This CL starts building type testing stubs specialzed for [Type] objects
we test against.
More specifically, it adds support for:
* Handling obvious fast cases on the call sites (while still having a
call to stub for negative case)
* Handling type tests against type parameters, by loading the value
of the type parameter on the call sites and invoking it's type testing stub.
* Specialzed type testing stubs for instantiated types where we can
do [CidRange]-based subtype-checks.
==> e.g. String/List<dynamic>
* Specialzed type testing stubs for instantiated types where we can
do [CidRange]-based subclass-checks for the class and
[CidRange]-based subtype-checks for the type arguments.
==> e.g. Widget<State>, where we know [Widget] is only extended and not
implemented.
* Specialzed type testing stubs for certain non-instantiated types where we
can do [CidRange]-based subclass-checks for the class and
[CidRange]-based subtype-checks for the instantiated type arguments and
cid based comparisons for type parameters. (Note that this fast-case migth
result in some false-negatives!)
==> e.g. _HashMapEntry<K, V>, where we know [_HashMapEntry] is only
extended and not implemented.
This optimizes cases where the caller uses `new HashMap<A, B>()` and only
uses `A` and `B` as key/values (and not subclasses of it). The false-negative
can occur when subtypes of A or B are used. In such cases we fall back to the
[SubtypeTestCache]-based imlementation.
Reviewed-on: https://dart-review.googlesource.com/44788
Relands 25f98bcc75
[VM] Introduction of type testing stubs - Part 3
The changes include:
* Make AssertAssignableInstr no longer have a call-summary, which
helps methods with several parameter checks by not having to
re-load/re-initialize type arguments registers
* Lazily create SubtypeTestCaches: We already go to runtime to warm up
the caches, so we now also create the caches on the first runtime
call and patch the pool entries.
* No longer load the destination name into a register: We only need
the name when we throw an exception, so it is not on the hot path.
Instead we let the runtime look at the call site, decoding a pool
index from the instructions stream. The destination name will be
available in the pool, at a consecutive index to the subtype cache.
* Remove the fall-through to N=1 case for probing subtypeing tests,
since those will always be handled by the optimized stubs.
* Do not generate optimized stubs for FutureOr<T> (so far it just
falled-through to TTS). We can make optimzed version of that later,
but it requires special subtyping rules.
* Local code quality improvement in the type-testing-stubs: Avoid
extra jump at last case of cid-class-range checks.
There are still a number of optimization opportunities we can do in
future changes.
Reviewed-on: https://dart-review.googlesource.com/46984
Relands 2c52480ec8
[VM] Introduction of type testing stubs - Part 4
In order to avoid generating type testing stubs for too many types in
the system - and thereby potentially cause an increase in code size -
this change introduces a smarter way to decide for which types we should
generate optimized type testing stubs.
The precompiler creates a [TypeUsageInfo] which we use to collect
information. More specifically:
a) We collect the destination types for all type checks we emit
(we do this inside AssertAssignableInstr::EmitNativeCode).
-> These are types we might want to generate optimized type testing
stubs for.
b) We collect type argument vectors used in instance creations (we do
this inside AllocateObjectInstr::EmitNativeCode) and keep a set of
of used type argument vectors for each class.
After the precompiler has finished compiling normal code we scan the set
of destination types collected in a) for uninstantiated types (or more
specifically, type parameter types).
We then propagate the type argument vectors used on object allocation sites,
which were collected in b), in order to find out what kind of types are flowing
into those type parameters.
This allows us to extend the set of types which we test against, by
adding the types that flow into type parameters.
We use this final augmented set of destination types as a "filter" when
making the decision whether to generate an optimized type testing stub
for a given type.
Reviewed-on: https://dart-review.googlesource.com/48640
Issue https://github.com/dart-lang/sdk/issues/32603
Closes https://github.com/dart-lang/sdk/issues/32852
Change-Id: Ib79fbe7f043aa88f32bddad62d7656c638914b44
Reviewed-on: https://dart-review.googlesource.com/50944
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Régis Crelier <regis@google.com>
Relands 165c583d57
[VM] Introduction of type testing stubs - Part 1
This CL:
* Adds a field to [RawAbstractType] which will always hold a pointer
to the entrypoint of a type testing stub
* Makes this new field be initialized to a default stub whenever a
instances are created (e.g. via Type::New(), snapshot reader, ...)
* Makes the clustered snapshotter write a reference to the
corresponding [RawInstructions] object when writing the field and do
the reverse when reading it.
* Makes us call the type testing stub for performing assert-assignable
checks.
To reduce unnecessary loads on callsites, we store the entrypoint of the
type testing stubs directly in the type objects. This means that the
caller of type testing stubs can simply branch there without populating
a code object first. This also means that the type testing stubs
themselves have no access to a pool and we therefore also don't hold on
to the [Code] object, only the [Instruction] object is necessary.
The type testing stubs do not setup a frame themselves and also have no
safepoint. In the case when the type testing stubs could not determine
a positive answer they will tail-call a general-purpose stub.
The general-purpose stub sets up a stub frame, tries to consult a
[SubtypeTestCache] and bails out to runtime if this was unsuccessful.
This CL is just the the first, for ease of reviewing. The actual
type-specialized type testing stubs will be generated in later CLs.
Reviewed-on: https://dart-review.googlesource.com/44787
Relands f226c22424
[VM] Introduction of type testing stubs - Part 2
This CL starts building type testing stubs specialzed for [Type] objects
we test against.
More specifically, it adds support for:
* Handling obvious fast cases on the call sites (while still having a
call to stub for negative case)
* Handling type tests against type parameters, by loading the value
of the type parameter on the call sites and invoking it's type testing stub.
* Specialzed type testing stubs for instantiated types where we can
do [CidRange]-based subtype-checks.
==> e.g. String/List<dynamic>
* Specialzed type testing stubs for instantiated types where we can
do [CidRange]-based subclass-checks for the class and
[CidRange]-based subtype-checks for the type arguments.
==> e.g. Widget<State>, where we know [Widget] is only extended and not
implemented.
* Specialzed type testing stubs for certain non-instantiated types where we
can do [CidRange]-based subclass-checks for the class and
[CidRange]-based subtype-checks for the instantiated type arguments and
cid based comparisons for type parameters. (Note that this fast-case migth
result in some false-negatives!)
==> e.g. _HashMapEntry<K, V>, where we know [_HashMapEntry] is only
extended and not implemented.
This optimizes cases where the caller uses `new HashMap<A, B>()` and only
uses `A` and `B` as key/values (and not subclasses of it). The false-negative
can occur when subtypes of A or B are used. In such cases we fall back to the
[SubtypeTestCache]-based imlementation.
Reviewed-on: https://dart-review.googlesource.com/44788
Relands 25f98bcc75
[VM] Introduction of type testing stubs - Part 3
The changes include:
* Make AssertAssignableInstr no longer have a call-summary, which
helps methods with several parameter checks by not having to
re-load/re-initialize type arguments registers
* Lazily create SubtypeTestCaches: We already go to runtime to warm up
the caches, so we now also create the caches on the first runtime
call and patch the pool entries.
* No longer load the destination name into a register: We only need
the name when we throw an exception, so it is not on the hot path.
Instead we let the runtime look at the call site, decoding a pool
index from the instructions stream. The destination name will be
available in the pool, at a consecutive index to the subtype cache.
* Remove the fall-through to N=1 case for probing subtypeing tests,
since those will always be handled by the optimized stubs.
* Do not generate optimized stubs for FutureOr<T> (so far it just
falled-through to TTS). We can make optimzed version of that later,
but it requires special subtyping rules.
* Local code quality improvement in the type-testing-stubs: Avoid
extra jump at last case of cid-class-range checks.
There are still a number of optimization opportunities we can do in
future changes.
Reviewed-on: https://dart-review.googlesource.com/46984
Relands 2c52480ec8
[VM] Introduction of type testing stubs - Part 4
In order to avoid generating type testing stubs for too many types in
the system - and thereby potentially cause an increase in code size -
this change introduces a smarter way to decide for which types we should
generate optimized type testing stubs.
The precompiler creates a [TypeUsageInfo] which we use to collect
information. More specifically:
a) We collect the destination types for all type checks we emit
(we do this inside AssertAssignableInstr::EmitNativeCode).
-> These are types we might want to generate optimized type testing
stubs for.
b) We collect type argument vectors used in instance creations (we do
this inside AllocateObjectInstr::EmitNativeCode) and keep a set of
of used type argument vectors for each class.
After the precompiler has finished compiling normal code we scan the set
of destination types collected in a) for uninstantiated types (or more
specifically, type parameter types).
We then propagate the type argument vectors used on object allocation sites,
which were collected in b), in order to find out what kind of types are flowing
into those type parameters.
This allows us to extend the set of types which we test against, by
adding the types that flow into type parameters.
We use this final augmented set of destination types as a "filter" when
making the decision whether to generate an optimized type testing stub
for a given type.
Reviewed-on: https://dart-review.googlesource.com/48640
Issue https://github.com/dart-lang/sdk/issues/32603
Change-Id: I6d33d4ca3d5187a1eb1664078c003061855f0160
Reviewed-on: https://dart-review.googlesource.com/50482
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
Relands 165c583d57
[VM] Introduction of type testing stubs - Part 1
This CL:
* Adds a field to [RawAbstractType] which will always hold a pointer
to the entrypoint of a type testing stub
* Makes this new field be initialized to a default stub whenever a
instances are created (e.g. via Type::New(), snapshot reader, ...)
* Makes the clustered snapshotter write a reference to the
corresponding [RawInstructions] object when writing the field and do
the reverse when reading it.
* Makes us call the type testing stub for performing assert-assignable
checks.
To reduce unnecessary loads on callsites, we store the entrypoint of the
type testing stubs directly in the type objects. This means that the
caller of type testing stubs can simply branch there without populating
a code object first. This also means that the type testing stubs
themselves have no access to a pool and we therefore also don't hold on
to the [Code] object, only the [Instruction] object is necessary.
The type testing stubs do not setup a frame themselves and also have no
safepoint. In the case when the type testing stubs could not determine
a positive answer they will tail-call a general-purpose stub.
The general-purpose stub sets up a stub frame, tries to consult a
[SubtypeTestCache] and bails out to runtime if this was unsuccessful.
This CL is just the the first, for ease of reviewing. The actual
type-specialized type testing stubs will be generated in later CLs.
Reviewed-on: https://dart-review.googlesource.com/44787
Relands f226c22424
[VM] Introduction of type testing stubs - Part 2
This CL starts building type testing stubs specialzed for [Type] objects
we test against.
More specifically, it adds support for:
* Handling obvious fast cases on the call sites (while still having a
call to stub for negative case)
* Handling type tests against type parameters, by loading the value
of the type parameter on the call sites and invoking it's type testing stub.
* Specialzed type testing stubs for instantiated types where we can
do [CidRange]-based subtype-checks.
==> e.g. String/List<dynamic>
* Specialzed type testing stubs for instantiated types where we can
do [CidRange]-based subclass-checks for the class and
[CidRange]-based subtype-checks for the type arguments.
==> e.g. Widget<State>, where we know [Widget] is only extended and not
implemented.
* Specialzed type testing stubs for certain non-instantiated types where we
can do [CidRange]-based subclass-checks for the class and
[CidRange]-based subtype-checks for the instantiated type arguments and
cid based comparisons for type parameters. (Note that this fast-case migth
result in some false-negatives!)
==> e.g. _HashMapEntry<K, V>, where we know [_HashMapEntry] is only
extended and not implemented.
This optimizes cases where the caller uses `new HashMap<A, B>()` and only
uses `A` and `B` as key/values (and not subclasses of it). The false-negative
can occur when subtypes of A or B are used. In such cases we fall back to the
[SubtypeTestCache]-based imlementation.
Reviewed-on: https://dart-review.googlesource.com/44788
Relands 25f98bcc75
[VM] Introduction of type testing stubs - Part 3
The changes include:
* Make AssertAssignableInstr no longer have a call-summary, which
helps methods with several parameter checks by not having to
re-load/re-initialize type arguments registers
* Lazily create SubtypeTestCaches: We already go to runtime to warm up
the caches, so we now also create the caches on the first runtime
call and patch the pool entries.
* No longer load the destination name into a register: We only need
the name when we throw an exception, so it is not on the hot path.
Instead we let the runtime look at the call site, decoding a pool
index from the instructions stream. The destination name will be
available in the pool, at a consecutive index to the subtype cache.
* Remove the fall-through to N=1 case for probing subtypeing tests,
since those will always be handled by the optimized stubs.
* Do not generate optimized stubs for FutureOr<T> (so far it just
falled-through to TTS). We can make optimzed version of that later,
but it requires special subtyping rules.
* Local code quality improvement in the type-testing-stubs: Avoid
extra jump at last case of cid-class-range checks.
There are still a number of optimization opportunities we can do in
future changes.
Reviewed-on: https://dart-review.googlesource.com/46984
Relands 2c52480ec8
[VM] Introduction of type testing stubs - Part 4
In order to avoid generating type testing stubs for too many types in
the system - and thereby potentially cause an increase in code size -
this change introduces a smarter way to decide for which types we should
generate optimized type testing stubs.
The precompiler creates a [TypeUsageInfo] which we use to collect
information. More specifically:
a) We collect the destination types for all type checks we emit
(we do this inside AssertAssignableInstr::EmitNativeCode).
-> These are types we might want to generate optimized type testing
stubs for.
b) We collect type argument vectors used in instance creations (we do
this inside AllocateObjectInstr::EmitNativeCode) and keep a set of
of used type argument vectors for each class.
After the precompiler has finished compiling normal code we scan the set
of destination types collected in a) for uninstantiated types (or more
specifically, type parameter types).
We then propagate the type argument vectors used on object allocation sites,
which were collected in b), in order to find out what kind of types are flowing
into those type parameters.
This allows us to extend the set of types which we test against, by
adding the types that flow into type parameters.
We use this final augmented set of destination types as a "filter" when
making the decision whether to generate an optimized type testing stub
for a given type.
Reviewed-on: https://dart-review.googlesource.com/48640
Issue https://github.com/dart-lang/sdk/issues/32603
Change-Id: I44a1d5d4b27454ae026aef2a301aada3dd399ea0
Reviewed-on: https://dart-review.googlesource.com/49861
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
This CL:
* Adds a field to [RawAbstractType] which will always hold a pointer
to the entrypoint of a type testing stub
* Makes this new field be initialized to a default stub whenever a
instances are created (e.g. via Type::New(), snapshot reader, ...)
* Makes the clustered snapshotter write a reference to the
corresponding [RawInstructions] object when writing the field and do
the reverse when reading it.
* Makes us call the type testing stub for performing assert-assignable
checks.
To reduce unnecessary loads on callsites, we store the entrypoint of the
type testing stubs directly in the type objects. This means that the
caller of type testing stubs can simply branch there without populating
a code object first. This also means that the type testing stubs
themselves have no access to a pool and we therefore also don't hold on
to the [Code] object, only the [Instruction] object is necessary.
The type testing stubs do not setup a frame themselves and also have no
safepoint. In the case when the type testing stubs could not determine
a positive answer they will tail-call a general-purpose stub.
The general-purpose stub sets up a stub frame, tries to consult a
[SubtypeTestCache] and bails out to runtime if this was unsuccessful.
This CL is just the the first, for ease of reviewing. The actual
type-specialized type testing stubs will be generated in later CLs.
Issue https://github.com/dart-lang/sdk/issues/31798
Change-Id: I174a11b3b812799f399a60af799144c2ba3c26ec
Reviewed-on: https://dart-review.googlesource.com/44787
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Régis Crelier <regis@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>
- Refactor the JumpToExceptionHandle code so that it is now built from
two pieces: JumpToFrame and RunExceptionHandler.
- Refactor the Simulator::Longjmp() code so that it is no longer
exception-specific. Instead it uses the RunExceptionHandler stub.
This makes it so that the JumpToFrame stub and Simulator::JumpToFrame
have the same semantics. This will make it easier to land the Rewind
changes I am working on.
There are some oddities for dbc.
BUG=
R=johnmccutchan@google.com
Review URL: https://codereview.chromium.org/2503653002 .
The call sequence is very similar to a classic IC call, except the guarded class and the target are loaded indirectly from the constant pool instead of as immediates. In the monomorphic case, we call directly to the expected target with a class check in the callee. In the unlinked, polymorphic and megamorphic cases, we call a stub; these case are now call-through instead of call-and-return.
Every code, except stubs involved in switchable calls, includes the class check sequence at the beginning. So we now distinguish between a checked and an unchecked entry point. Generated code except the switchable call continues to use the unchecked entry point.
PC offsets are calculated relative to the beginning of the instruction stream, rather than either entry point.
BUG=
R=fschneider@google.com
Review URL: https://codereview.chromium.org/2226893002 .
Also drop stub-code generation code, which pulled in large parts of the assembler as well.
This reduces the size of dart_precompiled/libdart_precompiled by around 100K on x64.
BUG=
R=rmacnak@google.com
Review URL: https://codereview.chromium.org/1560663002 .
- API breakage: Dart_IsolateBlocked, Dart_IsolateUnblocked -> Dart_ThreadDisableProfiling, Dart_ThreadEnableProfiling.
- Remove IsolateProfilerData.
- Move thread at blocking call count from isolate to thread.
- Always interrupt threads unless they are blocked.
- We can no longer count "idle" ticks.
- Only record sample if thread is the current mutator of an isolate.
- Refactor ThreadInterrupterCallback to ensure that Thread* is valid.
Threads are only ever sent signals if ThreadInterruptsEnabled is true. Which is controlled by two functions:
void DisableThreadInterrupts();
void EnableThreadInterrupts();
R=asiva@google.com, iposva@google.com
Review URL: https://codereview.chromium.org/1423473004 .
- API breakage: Dart_IsolateBlocked, Dart_IsolateUnblocked -> Dart_ThreadDisableProfiling, Dart_ThreadEnableProfiling.
- Remove IsolateProfilerData.
- Move thread at blocking call count from isolate to thread.
- Always interrupt threads unless they are blocked.
- We can no longer count "idle" ticks.
- Only record sample if thread is the current mutator of an isolate.
- Refactor ThreadInterrupterCallback to ensure that Thread* is valid.
Threads are only ever sent signals if ThreadInterruptsEnabled is true. Which is controlled by two functions:
void DisableThreadInterrupts();
void EnableThreadInterrupts();
R=asiva@google.com, iposva@google.com
Review URL: https://codereview.chromium.org/1412733008 .
Instead of calling code object directly, call indirectly and
pass the code object in a register. The object pool is then loaded from
the code object. This is another preparation step for making generated code
relocatable.
All non-ia32 platforms:
No entry patching.
ARM:
PC marker (now code object) moves to the same place as on x64 (below saved PP, above saved FP).
R9 is now used as PP, R10 as CODE_REG.
BUG=
R=rmacnak@google.com
Review URL: https://codereview.chromium.org//1192103004 .
- Load precompiled stub code from the snapshot.
- Mark isolates reading from precompiled snapshots as not allowed to compile.
- Reset static field values during precompilation.
- Don't run the program after generating a precompiled snapshot.
Fails sooner in loading precompiled snapshots due to null Instructions.
R=asiva@google.com
Review URL: https://codereview.chromium.org//1311403009 .
This enables thread-safe logging (e.g., ISL_Print, which will soon be renamed to THR_Print), which is needed for concurrent
marking (DetachCode) and compilation.
Make finalization of GC marking tasks concurrent, now that it's thread-safe.
BUG=
R=iposva@google.com
Review URL: https://codereview.chromium.org//1314673008 .
This makes the code in the code generator independent from how stubs
are actually called (i.e. directly embedding the target address, or
indirectly by loading the target address from the code object).
BUG=
R=rmacnak@google.com
Review URL: https://codereview.chromium.org//1270803003 .
This allows to make the last explicitly named stubs shared between isolates.
When sharing code stubs, we can't do patching at their entry anymore.
Therefore, I had to remove patching support of the array allocation stub.
Is this a functionality we want to keep?
The change is mostly performance-neutral because optimized code has an inlined fast
path for array allocation and only uses the stub for the slow-case.
The only isolate-specific stubs left are object allocation stubs which are
associated with their Class are per-isolate.
Since this CL removes any isolate-specific stubs from StubCode, it becomes AllStatic.
BUG=
R=koda@google.com
Review URL: https://codereview.chromium.org//1247783002 .
This CL also lifts the restriction that the object pool can't be used
in VM isolate code on x64 and arm64.
Stubs that perform allocation can't be shared yet, because the inline allocation
code is not yet isolate-independent. This will be added in a separate CL.
BUG=
R=rmacnak@google.com
Review URL: https://codereview.chromium.org//1229283002 .
This adds meta-information to object pool entries to allow storing
untagged immediates or code addresses (ExternalLabel) directly.
This eliminates the need to generate extra code to preserve the LSB
when storing immediates as smis (x64, arm64).
BUG=
Review URL: https://codereview.chromium.org//1175523002.
By moving all stubs that do runtime calls into the isolate
we don't need to cache the current isolate in each context
object.
This saves space on each context at the cost of duplicating stubs
in each isolate. Most stubs are already isolate-specific and the total number
of stubs is small enough for this to be a good trade-off.
R=vegorov@google.com
Review URL: https://codereview.chromium.org//668193002
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@41279 260f80e4-7a28-3924-810f-c04153c831b5
Régis Crelier