Commit Graph

42 Commits

Author SHA1 Message Date
Ryan Macnak 8db0a975c1 [vm] Allow garbage in the upper-half of compressed Smis.
Allows removing a branch when decompressing pointers and removing fixup sign-extension after Smi ops that use 32-bit ops to detect overflow. Increases the code size of indexed and stores for some widths due to addressing mode limitations.

TEST=ci
Change-Id: Ia48353cccbbc586dd0d2e055a843c65e37c63a30
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/185660
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Liam Appelbe <liama@google.com>
2021-03-11 19:39:01 +00:00
Martin Kustermann 0f76981bb1 [vm/concurrency] Change references to class_table/object_store/heap from Isolate to IsolateGroup
As part of making the compiler and other subsystems independent
of `Isolate` we have to move various state from `Isolate` to
`IsolateGroup`.

The class_table and object_store were already moved to `IsolateGroup`.

This CL only replaces usages of `Isolate::{object_store,class_table}`
with the equivalent in `IsolateGroup`.

Issue https://github.com/dart-lang/sdk/issues/36097

TEST=Pure refactoring - relying on existing test coverage.

Change-Id: I34a0682d715b054d6c5faff077a513980f59a348
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/177126
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
2021-01-06 15:22:11 +00:00
Tess Strickland e7a2fbe692 [vm/compiler] Unify TTS implementations across architectures.
The only architecture-specific part of type testing stubs (TTS) is which
registers get saved/restored across SubtypeTestCache stub calls in the
slow TTS implementation, which is now a register mask constant in the
TypeTestABI struct.

This CL also:

* Creates a single definition of OperandSize in assembler_base.h. Moves
  OperandSize into the compiler namespace.  assembler_base.h. Renames
  constants common to all architectures to neutral names (e.g., kWord =>
  kFourBytes), since "word" has different meanings across architectures.

* Creates a new JumpDistance enum for kNearJump/kFarJump in
  AssemblerBase and replace existing bool uses with the constants.

* Adds JumpDistance arguments to some of the generalized Assembler
  methods so they aren't forced to use far jumps on IA32/X64. These
  added JumpDistance arguments are ignored on ARM architectures.

* Adds a new generalized Assembler::LoadIndexedPayload method for
  loading indexed objects out of post-header variable-length payloads.

* Moved the OperandSize argument for LoadForOffset and similar methods
  on 32-bit ARM from being the first argument to being the second to
  last argument just to match other architectures, and to allow it to
  have a default value of kFourBytes.

TEST=Run on trybots of all architectures.

Cq-Include-Trybots: luci.dart.try:vm-kernel-linux-debug-x64-try,vm-kernel-nnbd-linux-debug-x64-try,vm-kernel-linux-debug-ia32-try,vm-kernel-nnbd-linux-debug-ia32-try,vm-kernel-precomp-linux-debug-simarm_x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-nnbd-linux-debug-simarm_x64-try,vm-kernel-precomp-nnbd-linux-debug-x64-try,vm-kernel-linux-release-simarm-try,vm-kernel-linux-release-simarm64-try,vm-kernel-nnbd-linux-release-simarm-try,vm-kernel-nnbd-linux-release-simarm64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-nnbd-linux-release-simarm64-try
Change-Id: Ia930613e96db4d1ab324c5a355dca8994d2a77f0
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/172160
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2020-11-17 15:09:47 +00:00
Aske Simon Christensen 99bd9d7db5 [vm, gardening] Initialize target array in movs tests to satisfy msan.
Fixes https://github.com/dart-lang/sdk/issues/42289

Change-Id: I13630b44d0c5bf5ec51256fb1fac41f812dd3e7e
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/150984
Auto-Submit: Aske Simon Christensen <askesc@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2020-06-12 12:03:02 +00:00
Aske Simon Christensen e35ca30ca5 Reland "[vm] MemoryCopy instruction for copying between typed data and strings."
This is a reland of 6ecd8a10ea

Original change's description:
> [vm] MemoryCopy instruction for copying between typed data and strings.
> 
> Used for copying the bytes from the Uint8List to the _OneByteString in
> String.fromCharCodes and the pure-ASCII case of UTF-8 decoding.
> 
> Issue https://github.com/dart-lang/sdk/issues/42072
> Closes https://github.com/dart-lang/sdk/issues/41703
> 
> Change-Id: I1ae300222877d1c6e64e32c2f40b8fb187a584c0
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/149500
> Commit-Queue: Aske Simon Christensen <askesc@google.com>
> Reviewed-by: Martin Kustermann <kustermann@google.com>

Change-Id: Ia231c521e5f2db168cfc6094dfc7322327dedc6d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/150925
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Aske Simon Christensen <askesc@google.com>
2020-06-11 12:29:19 +00:00
Ryan Macnak d1b0713e8b Revert "[vm] MemoryCopy instruction for copying between typed data and strings."
This reverts commit 6ecd8a10ea.

Reason for revert: Breaks ABI

Original change's description:
> [vm] MemoryCopy instruction for copying between typed data and strings.
> 
> Used for copying the bytes from the Uint8List to the _OneByteString in
> String.fromCharCodes and the pure-ASCII case of UTF-8 decoding.
> 
> Issue https://github.com/dart-lang/sdk/issues/42072
> Closes https://github.com/dart-lang/sdk/issues/41703
> 
> Change-Id: I1ae300222877d1c6e64e32c2f40b8fb187a584c0
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/149500
> Commit-Queue: Aske Simon Christensen <askesc@google.com>
> Reviewed-by: Martin Kustermann <kustermann@google.com>

TBR=kustermann@google.com,askesc@google.com

Change-Id: I5fc0b58da80dca23c91b57ec2833492e9d0885a8
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/150802
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2020-06-10 18:41:55 +00:00
Aske Simon Christensen 6ecd8a10ea [vm] MemoryCopy instruction for copying between typed data and strings.
Used for copying the bytes from the Uint8List to the _OneByteString in
String.fromCharCodes and the pure-ASCII case of UTF-8 decoding.

Issue https://github.com/dart-lang/sdk/issues/42072
Closes https://github.com/dart-lang/sdk/issues/41703

Change-Id: I1ae300222877d1c6e64e32c2f40b8fb187a584c0
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/149500
Commit-Queue: Aske Simon Christensen <askesc@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2020-06-10 14:40:17 +00:00
Aart Bik ea969c358e [vm/assembler] Split popcnt and lzcnt tests over feature set
Rationale:
Some processors may support just popcnt and, in theory,
some just lzcnt. This change makes the test more
specific. The bsf/bsr tests are never skipped anymore.
Change-Id: I0e7b8772789473ce238f0c5c93378c06c39c695b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/117940
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Aart Bik <ajcbik@google.com>
2019-09-18 23:54:26 +00:00
Aart Bik 51d6145e77 [vm/assembler] Skip tests on hosts without POPCNT/LZCNT
Change-Id: I49552c67d908d941eb08ab0a5c49cca4c39148bc
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/117920
Reviewed-by: Alexander Aprelev <aam@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Aart Bik <ajcbik@google.com>
2019-09-18 22:17:35 +00:00
Aart Bik 0ad30fafc1 [vm/assembler] Added cpufeatures, added LZCNT (IA32/X64)
Rationale:
We are adding library support for bit operations:
  lowZeroBitCount/highZeroBitCount/nonZeroBitCount
The added features will enable very efficient direct
native implementations of these operations in the
DartVM codegen.

https://github.com/dart-lang/sdk/issues/38346

Change-Id: Id734a7590666c6abdc2a683a240094c6bf6cd46a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/117768
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Aart Bik <ajcbik@google.com>
2019-09-18 19:47:29 +00:00
Aart Bik fc4021b68d [vm/assembler] add support for bsf, bsr, popcnt (IA32/X64)
Rationale:
We are adding library support for bit operations:
  lowZeroBitCount/highZeroBitCount/nonZeroBitCount
The added instructions for IA32 and X64 will enable
very efficient direct native implementations of
these operations in the DartVM codegen.

https://github.com/dart-lang/sdk/issues/38346

Change-Id: I04da6138eed45eb7b21cc310594c5c7ba7942750
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/117585
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Aart Bik <ajcbik@google.com>
2019-09-17 21:12:11 +00:00
Aart Bik 451a7dd4ea [vm/assembler] Add IMUL with implicit operands
Rationale:
Needed for an upcoming improvement of DIV/MOD by constant.

https://github.com/dart-lang/sdk/issues/37789

Change-Id: I3966049a3f14fd3becec797c4bc0038f2852bc1b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/114680
Commit-Queue: Aart Bik <ajcbik@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
2019-08-28 00:17:13 +00:00
Ryan Macnak 0e8656e045 [vm, compiler] Shorter invocation counter check.
Remove the optimization function stub and self function from the constant pool of every unoptimized function.

Remove one PP move from unoptimized frame entry.

Bug: https://github.com/dart-lang/sdk/issues/36409
Change-Id: Idbe37ce36b57dc316a131e6c83742ee2b3df4a0d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/102660
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Aart Bik <ajcbik@google.com>
2019-05-16 23:04:22 +00:00
Martin Kustermann 832668ff6c Reland "[Infra] Let run_vm_tests --list output a test expectation marker"
Due to not having support for __VA_OPT__ yet the CL introduces a new
wet of macros ..._WITH_EXPECTATIONS() which can be given an expectation
marker.

Change-Id: I33812937f1b226fa89b3ab17a8a3483914abf2e4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/100643
Reviewed-by: Stevie Strickland <sstrickl@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
2019-04-26 12:15:19 +00:00
Vyacheslav Egorov f496e538f4 [vm] Decouple assemblers from runtime.
This is the next step towards preventing compiler from directly peeking
into runtime and instead interact with runtime through a well defined
surface. The goal of the refactoring to locate all places where compiler
accesses some runtime information and partion those accesses into two
categories:

- creating objects in the host runtime (e.g. allocating strings, numbers, etc)
during compilation;
- accessing properties of the target runtime (e.g. offsets of fields) to
embed those into the generated code;

This change introduces dart::compiler and dart::compiler::target namespaces.

All code in the compiler will gradually be moved into dart::compiler namespace.
One of the motivations for this change is to be able to prevent access to
globally defined host constants like kWordSize by shadowing them in the
dart::compiler namespace.

The nested namespace dart::compiler::target hosts all information about
target runtime that compiler could access, e.g. compiler::target::kWordSize
defines word size of the target which will eventually be made different
from the host kWordSize (defined by dart::kWordSize).

The API for compiler to runtime interaction is placed into compiler_api.h.

Note that we still permit runtime to access compiler internals directly -
this is not going to be decoupled as part of this work.

Issue https://github.com/dart-lang/sdk/issues/31709

Change-Id: If4396d295879391becfa6c38d4802bbff81f5b20
Reviewed-on: https://dart-review.googlesource.com/c/90242
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2019-01-25 16:45:13 +00:00
Samir Jindel 921e62f1bf [vm] Introduce multiple entrypoints to AOT.
Cq-Include-Trybots: luci.dart.try:vm-kernel-win-release-x64-try, vm-kernel-optcounter-threshold-linux-release-x64-try, vm-kernel-precomp-linux-debug-x64-try, vm-kernel-precomp-linux-release-simarm-try, vm-kernel-precomp-linux-release-simarm64-try, vm-kernel-precomp-linux-release-x64-try, vm-kernel-precomp-win-release-x64-try
Change-Id: I8643033febf9bdc57c8298dca5f43346fb8bf6d1
Reviewed-on: https://dart-review.googlesource.com/c/80304
Commit-Queue: Samir Jindel <sjindel@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
2018-12-07 13:19:24 +00:00
Ryan Macnak 81d296c593 [vm, x64] Avoid use of preserved register in Testb3.
Fixes crash when compiled with ASAN.

Change-Id: Ib457728f156d7a8d3beafa4ae134fc884ab2679b
Reviewed-on: https://dart-review.googlesource.com/71233
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2018-08-23 01:23:49 +00:00
Ryan Macnak d6edd45d9a [vm, x64] Add missing addressing mode for testb.
To be used by the incremental write barrier.

Bug: https://github.com/dart-lang/sdk/issues/34002
Change-Id: I1f5214b5abe348fbb4eaa399819b01e515b085fb
Reviewed-on: https://dart-review.googlesource.com/71060
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Aart Bik <ajcbik@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2018-08-22 19:08:17 +00:00
Samir Jindel d8a4a3896a [vm] Multiple entrypoints: backend/assembler support.
Test Plan:

Will be tested by following revisions which introduce optimizations that invoke the
new entrypoint.

Change-Id: I56d714bceb92c44a13c46d52457154b82577aa8c
Cq-Include-Trybots: luci.dart.try:vm-kernel-win-release-x64-try,vm-kernel-optcounter-threshold-linux-release-x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-linux-release-x64-try,vm-kernel-precomp-win-release-x64-try
Reviewed-on: https://dart-review.googlesource.com/67345
Commit-Queue: Samir Jindel <sjindel@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
2018-08-16 17:15:32 +00:00
Martin Kustermann 3b414a277c Reland "[VM] Introduction of type testing stubs - Part 1-4"
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>
2018-04-13 09:06:56 +00:00
Ryan Macnak b3c94b5d52 Revert "Reland "[VM] Introduction of type testing stubs - Part 1-4""
This reverts commit 34763bc4c9.

Bug: https://github.com/dart-lang/sdk/issues/32852
Change-Id: I2131907d7036644707d5109a951969fc48dd74e1
Reviewed-on: https://dart-review.googlesource.com/50842
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
2018-04-11 22:42:59 +00:00
Martin Kustermann 34763bc4c9 Reland "[VM] Introduction of type testing stubs - Part 1-4"
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>
2018-04-10 12:20:10 +00:00
Martin Kustermann 1e997ee6b7 Revert "Reland "[VM] Introduction of type testing stubs - Part 1-4""
This reverts commit 8054409a02.

Reason for revert: Potential cause of flakes, not entirely clear yet if it was caused by this CL.

Change-Id: Icb119a107f22245ba2f303c7f2ae11f061f605f5
Reviewed-on: https://dart-review.googlesource.com/50261
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
2018-04-09 14:29:07 +00:00
Martin Kustermann 8054409a02 Reland "[VM] Introduction of type testing stubs - Part 1-4"
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>
2018-04-09 11:25:36 +00:00
Martin Kustermann dbb1d3d44f Revert "[VM] Introduction of type testing stubs - Part 1-4"
This reverts commit 2c52480ec8.
This reverts commit 25f98bcc75.
This reverts commit f226c22424.
This reverts commit 165c583d57.

Change-Id: I3892d672b9ca0b0acc0b9b83c32ecc92355839c2
Reviewed-on: https://dart-review.googlesource.com/49843
Reviewed-by: Martin Kustermann <kustermann@google.com>
2018-04-06 08:35:01 +00:00
Martin Kustermann 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.

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>
2018-04-06 07:00:50 +00:00
Erik Corry 235e62264e [VM] Reland Support some 32bit instructions in 64bit assemblers.
These instructions will soon be used for for smaller (32 bit) Smis.
Also fix broken ubfiz instruction in ARM64 assembler.

This reland fixes the disassembler test that used Stop
instructions which disassemble differently on Mac
because constants have higher addresses.

Originally reviewed at
https://dart-review.googlesource.com/c/sdk/+/43668

Fix assembler test on Mac

R=kustermann@google.com

Change-Id: I61f8626184af495f18a74b5fef07bad02b6615e9
Reviewed-on: https://dart-review.googlesource.com/45240
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Erik Corry <erikcorry@google.com>
2018-03-06 10:50:21 +00:00
Erik Corry 3ac86d759e Revert "[VM] Support some 32bit instructions in 64bit assemblers."
This reverts commit a5f173f165.

Reason for revert: Some test failures.

Original change's description:
> [VM] Support some 32bit instructions in 64bit assemblers.
> 
> These instructions will soon be used for for smaller (32 bit) Smis.
> 
> Also fix broken ubfiz instruction in ARM64 assembler.
> 
> R=​kustermann@google.com
> 
> Change-Id: I9068a1c4281047dbd7c1c447fc32ac0e92c89e9d
> Reviewed-on: https://dart-review.googlesource.com/43668
> Reviewed-by: Martin Kustermann <kustermann@google.com>
> Reviewed-by: Vyacheslav Egorov <vegorov@google.com>

TBR=vegorov@google.com,kustermann@google.com,erikcorry@google.com

Change-Id: I0991712936d903f2cb1f3851c919ed6171a96711
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/44981
Reviewed-by: Erik Corry <erikcorry@google.com>
Commit-Queue: Erik Corry <erikcorry@google.com>
2018-03-05 15:29:56 +00:00
Erik Corry a5f173f165 [VM] Support some 32bit instructions in 64bit assemblers.
These instructions will soon be used for for smaller (32 bit) Smis.

Also fix broken ubfiz instruction in ARM64 assembler.

R=kustermann@google.com

Change-Id: I9068a1c4281047dbd7c1c447fc32ac0e92c89e9d
Reviewed-on: https://dart-review.googlesource.com/43668
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
2018-03-05 14:45:23 +00:00
Erik Corry 1dec18e2cf [VM] Make x64 assembler more regular
Apart from removing almost 1000 lines of very repetitive code, the idea here is
to change the assembler from a huge pile of arbitrary code into something that
can be used to generate tables of opcodes and their structure. Later, I'd like to
use this to make the disassembler more table driven and less arbitrary, and
perhaps build an x86 simulator in the same vein as the ARM simulator, which
would help me debug (I find the ARM simulator very useful when making low level
changes to the VM and miss its functionality on x86).

R=vegorov@google.com

Bug:
Change-Id: I1ae2c1696f88b67862843c9ac05c827a7c9b9a6e
Reviewed-on: https://dart-review.googlesource.com/25241
Commit-Queue: Erik Corry <erikcorry@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
2017-12-12 14:14:45 +00:00
Ryan Macnak fda4ab3dbf [vm] Move the info_array for ObjectPool inline.
The info_array is needed to visit an ObjectPool's pointers, requiring the compactor to move the info_array's body before forwarding the ObjectPool's pointers. Moving the info_array inline remove this constraint on the compactor.

Also saves 3 words per ObjectPool modulo allocation size rounding.

Bug: https://github.com/dart-lang/sdk/issues/30978
Change-Id: I94de0e4b7356d46fb145efee7ab14abd7473eb4c
Reviewed-on: https://dart-review.googlesource.com/27480
Reviewed-by: Erik Corry <erikcorry@google.com>
2017-12-08 20:42:51 +00:00
Erik Corry 1d9ff70a08 [VM] Pick more compact instruction encodings on x64
Several tricks here:
* When zeroing registers we can use xorl instead of xorq because the 'l'
  variant will zero the top bits.
* test and 'and' instructions with immediate arguments can use 8-bit and 32 bit
  variants more heavily.
* mov reg, immediate can use more compact encodings when sign-extension is not
  needed.

Performance is better than +1% when measured on Dart2JS.

R=vegorov@google.com

Intel optimization manual says: "Assembly/Compiler Coding Rule 64. (H impact, M
generality) Use the 32-bit versions of instructions in 64-bit mode to reduce
code size unless the 64-bit version is necessary to access 64-bit data or
additional registers."
Bug:
Change-Id: I2a989315c45f8d8ebab719653fbfa2b18ebb77c9
Reviewed-on: https://dart-review.googlesource.com/23400
Commit-Queue: Erik Corry <erikcorry@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
2017-11-24 10:53:17 +00:00
Erik Corry d300b08e35 [VM] Use X64 disassembler for IA32 and X64 (reland)
R=vegorov@google.com

This removes the IA32 disassembler and uses the X64 disassembler for
both variants.  Instructions that were in the IA32 assembler, but not
supported by the X64 disassembler have been added.  It also adds some
regression tests for a lot of the disassembler output.
Bug:
Change-Id: I243abbb04c3a77810ce96ca74f7f42a5a1aea0cf
Reviewed-on: https://dart-review.googlesource.com/22982
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Commit-Queue: Erik Corry <erikcorry@google.com>
2017-11-22 12:04:18 +00:00
Erik Corry 80992a5a09 Revert "[VM] Use X64 disassembler for IA32 and X64"
This reverts commit 9e42f006d9.
due to test failures on non-Linux platforms.

R=karlklose@google.com

Bug:
Change-Id: I5dc40da75d8d89fca8fce98a69a39d767493af1b
Reviewed-on: https://dart-review.googlesource.com/22921
Reviewed-by: Karl Klose <karlklose@google.com>
2017-11-22 09:11:12 +00:00
Erik Corry 9e42f006d9 [VM] Use X64 disassembler for IA32 and X64
R=vegorov@google.com

Bug:
Change-Id: I19b1f58e16ea35dc81b941c54e6e57b97cad3d74
Reviewed-on: https://dart-review.googlesource.com/22020
Commit-Queue: Erik Corry <erikcorry@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
2017-11-22 08:01:07 +00:00
Erik Corry f3be82bb34 [VM] Make x86 and x64 assemblers less repetitive
This also means that an orthogonal selection of the core ALU instructions
are available so future programmers don't have to add instructions
to the assembler as needed, which tends to slow down progress.

R=vegorov@google.com

Bug:
Change-Id: I5fea72c70ea7ffbae8efad85aef4ecc96c235cb6
Reviewed-on: https://dart-review.googlesource.com/21140
Commit-Queue: Erik Corry <erikcorry@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
2017-11-16 14:18:41 +00:00
Erik Corry d0abf73d12 [VM] Add bt immediate instruction for IA32, X64
R=vegorov@google.com

Bug:
Change-Id: I89640ac207877c7b564b6e9713ee72895ca02054
Reviewed-on: https://dart-review.googlesource.com/17443
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Commit-Queue: Erik Corry <erikcorry@google.com>
2017-10-31 17:06:55 +00:00
Vyacheslav Egorov 579b06ed4c [VM] Improve code patterns for various SIMD instructions on ia32/x64.
There are three types of changes in this CL:

* If there is a repeated per-component sequence of instruction, it is
replaced with a loop (e.g. see Float32x4ConstructorInstr);
* When accessing components in the spilled SIMD values don't use 
hardcoded constants but instead compute the offset from op_kind() 
(e.g. kFloat32x4WithZ accesses component with index kFloat32x4WithZ - kFloat32x4WithX = 2).
This allows to share code.
* Use setcc and arithmetic to materialize result of the comparison instead of branches;
* Use the fact that true and false are consecutive values in the Thread structure to convert
0/1 to true/false (see Int32x4GetFlagInstr)
* Extract Int32x4 components without spilling the whole SIMD value to the 
stack (see Int32x4GetFlagInstr).

This extracted from a larger refactoring CL: https://dart-review.googlesource.com/c/sdk/+/10120

Bug: https://github.com/dart-lang/sdk/issues/30949
Change-Id: Ic3757789a1ca621b267150133991fed5b85da633
Reviewed-on: https://dart-review.googlesource.com/11080
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Zach Anderson <zra@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
2017-10-04 20:03:41 +00:00
Régis Crelier 6cfac06ad2 [gardening] Fix recently added assembly test.
Change-Id: Ibe3b1ec0e8969159fb04dcd5eac67088e05d44e8
Reviewed-on: https://dart-review.googlesource.com/10821
Reviewed-by: Régis Crelier <regis@google.com>
2017-10-04 00:25:38 +00:00
Lasse Reichstein Holst Nielsen 422bc2ebcc Make X64 assembler setcc operation accept more byte registers.
Bug: http://dartbug.com/30952
Change-Id: If33b439e056b777f723e4be20f892aa2ca64c1ee
Reviewed-on: https://dart-review.googlesource.com/10380
Commit-Queue: Lasse R.H. Nielsen <lrn@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
2017-10-03 16:05:39 +00:00
Erik Corry 06abc845ea [VM] Fix x64 assembler for subl immediate instruction
R=regis@google.com

Bug:
Change-Id: I8344bce9b7b4bbafc48df98b7c212084826f5372
Reviewed-on: https://dart-review.googlesource.com/5221
Reviewed-by: Régis Crelier <regis@google.com>
Commit-Queue: Erik Corry <erikcorry@google.com>
2017-09-12 21:08:51 +00:00
Vyacheslav Egorov 8a179fb953 [VM, Compiler] Move compiler to a separate folder.
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>
2017-09-04 15:15:18 +00:00