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  1. 27 Nov, 2017 1 commit
    • Sathya Gunasekaran's avatar
      [class] Store class fields initializer on the constructor · 4ca9d843
      Sathya Gunasekaran authored 
      Previously, the class fields initializer function was stored on a
synthetic context allocated variable. This approach had sevaral
problems:

- We didn't know that class literal had fields until after we had
completely parsed the class literal. This meant that we had to go back
and fix up the scope of the constructor to have this synthetic
variable. This resulted in mismatch between parser and preparsed scope
data.

- This synthetic variable could potentially resolve to an initializer
of an outer class.

For ex:
class X extends Object {
  c = 1;
  constructor() {
    var t = () => {
      class P extends Object {
        constructor() {
          var t = () => { super(); };
          t();
        }
      }
      super();
    }
    t();
  }
}

In this the inner class P could access the outer class X's initiliazer
function. We would have to maintain extra metadata to make sure this
doesn't happen.

Instead this new approach uses a private symbol to store the
initializer function on the class constructor itself.

For the base constructor case, we can simply check for a bit on the
constructor function literal to see if we need to emit code that loads
and calls this initializer function. Therefore, we don't pay the cost
of loading this function in case there are no class fields.

For the derived constructor case, there are two possiblities:
(a) We are in a super() call directly in the derived constructor:

In this case we can do a check similar to the base constructor check,
we can check for a bit on the derived constructor and emit code for
loading and calling the initializer function.

This is usually the common case and we don't pay any cost for not using
class fields.

(b) We are in a super() call inside an arrow function in the derived
constructor:

In this case, we /always/ emit code to load and call the initializer
function. If the function doesn't exist then we have undefined and we
don't call anything. Otherwise we call the function.

super() can't be called twice so even if we emit code to load and call
the initializer function multiple times, it doesn't matter because it
would have already been an error.

Bug: v8:5367
Change-Id: I7f77cd6493ff84cf0e430a8c1039bc9ac6941a88
Reviewed-on: https://chromium-review.googlesource.com/781660
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
Reviewed-by: 's avatarMythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49628}
      4ca9d843
  3. 16 Nov, 2017 1 commit
  5. 09 Nov, 2017 1 commit
    • Ross McIlroy's avatar
      [Ast] Teach Ast Printer to print raw literal values. · ff4e4ab4
      Ross McIlroy authored 
      Converts the ast prettyprinter to printing literals from the raw values
rather than internalized on-heap strings. This enables ast printing before
internalizing, and means we can avoid use of the isolate in the interpreter's
off-thread phase.

Also removes --print-builtin-ast and relies on just --print-ast to print
everything.

Finally, converts FunctionLiteral's debug_name function to return a
char[] which is created from the raw name literal where it exists, rather
than relying on the value having been internalized.

BUG=v8:5203

Change-Id: Ib69f754e254736f415db38713e6209465817e6f1
Reviewed-on: https://chromium-review.googlesource.com/758681Reviewed-by: 's avatarAdam Klein <adamk@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49276}
      ff4e4ab4
  7. 03 Nov, 2017 2 commits
    • Ross McIlroy's avatar
      Revert "[Ast] Teach Ast Printer to print raw literal values." · 5dc02ef2
      Ross McIlroy authored 
      This reverts commit c60934e9.

Reason for revert: breaks nosnap build


Original change's description:
> [Ast] Teach Ast Printer to print raw literal values.
> 
> Converts the ast prettyprinter to printing literals from the raw values
> rather than internalized on-heap strings. This enables ast printing before
> internalizing, and means we can avoid use of the isolate in the interpreter's
> off-thread phase.
> 
> Also removes --print-builtin-ast and relies on just --print-ast to print
> everything.
> 
> Finally, converts FunctionLiteral's debug_name function to return a
> char[] which is created from the raw name literal where it exists, rather
> than relying on the value having been internalized.
> 
> BUG=v8:5203
> 
> Change-Id: I0e358d6acc9ae4516ed49e7a763e208fea5fcf66
> Reviewed-on: https://chromium-review.googlesource.com/749261
> Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
> Reviewed-by: Adam Klein <adamk@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49119}

TBR=rmcilroy@chromium.org,adamk@chromium.org

Change-Id: Ic9d511f5107666a2f6a2bf59d8e93643c32d4d2b
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:5203
Reviewed-on: https://chromium-review.googlesource.com/753627Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49120}
      5dc02ef2
    • Ross McIlroy's avatar
      [Ast] Teach Ast Printer to print raw literal values. · c60934e9
      Ross McIlroy authored 
      Converts the ast prettyprinter to printing literals from the raw values
rather than internalized on-heap strings. This enables ast printing before
internalizing, and means we can avoid use of the isolate in the interpreter's
off-thread phase.

Also removes --print-builtin-ast and relies on just --print-ast to print
everything.

Finally, converts FunctionLiteral's debug_name function to return a
char[] which is created from the raw name literal where it exists, rather
than relying on the value having been internalized.

BUG=v8:5203

Change-Id: I0e358d6acc9ae4516ed49e7a763e208fea5fcf66
Reviewed-on: https://chromium-review.googlesource.com/749261
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: 's avatarAdam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49119}
      c60934e9
  9. 27 Oct, 2017 1 commit
    • Adam Klein's avatar
      [ast] Move AstValue implementation into Literal · 317cf321
      Adam Klein authored 
      This eliminates the AstValue class, effectively moving its
implementation into the Literal AstNode. This should cause
no difference in behavior, but it does signal some shifts
in the underlying system. Biggest changes include:

  - Reduction in AST memory usage
  - No duplicate HeapNumbers in Ignition constant pools
  - Non-String values are allocated either at constant pool
    creation time (or at boilerplate creation time for literals),
    rather than at AstValueFactory::Internalize() time.

There are a variety of test-only/debug-only changes due to these
switches as well.

Bug: v8:6984
Change-Id: I5f178040ce2796d4e7370c24d1063419e1c843a1
Reviewed-on: https://chromium-review.googlesource.com/731111
Commit-Queue: Adam Klein <adamk@chromium.org>
Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
Reviewed-by: 's avatarMarja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49013}
      317cf321
  11. 25 Oct, 2017 1 commit
    • Leszek Swirski's avatar
      [parser] Add an n-ary node for large binop chains · 52ef2a1c
      Leszek Swirski authored 
      Expressions of the form

    a_0 + a_1 + a_2 + a_3 + ... + a_n

seem to be reasonably common for cases such as building templates.
However, parsing these expressions results in a n-deep expression tree:

           ...
          /
         +
        / \
       +  a_2
      / \
    a_0 a_1

Traversing this tree during compilation can cause a stack overflow when n is
large.

Instead, for left-associate operations such as add, we now build up an
n-ary node in the parse tree, of the form

         n-ary +
       /  |      \
      /   |  ...  \
    a_0  a_1      a_n

The bytecode compiler can now iterate through the child expressions
rather than recursing.

This patch only supports arithmetic operations -- subsequent patches
will enable the same optimization for logical tests and comma
expressions.

Bug: v8:6964
Bug: chromium:724961
Bug: chromium:731861
Bug: chromium:752081
Bug: chromium:771653
Bug: chromium:777302
Change-Id: Ie97e4ce42506fe62a7bc4ffbdaa90a9f698352cb
Reviewed-on: https://chromium-review.googlesource.com/733120
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarMarja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48920}
      52ef2a1c
  13. 23 Oct, 2017 1 commit
  15. 19 Oct, 2017 1 commit
  17. 16 Oct, 2017 1 commit
  19. 13 Oct, 2017 1 commit
  21. 05 Oct, 2017 2 commits
  23. 22 Sep, 2017 1 commit
    • Benedikt Meurer's avatar
      [es2015] Introduce dedicated GetTemplateObject bytecode. · 79ac69b8
      Benedikt Meurer authored 
      Tagged templates were previously desugared during parsing using some
combination of runtime support written in JavaScript and C++, which
prevented some optimizations from happening, namely the constant folding
of the template object in TurboFan optimized code. This CL adds a new
bytecode GetTemplateObject (with a corresponding GetTemplateObject AST
node), which represents the abstract operation in the ES6 specification
and allows TurboFan to simply constant-fold template objects at compile
time (which is explicitly supported by the specification).

This also pays down some technical debt by removing the template.js
runtime support and therefore should reduce the size of the native
context (snapshot) a bit.

With this change in-place the ES6 version microbenchmark in the
referenced tracking bug is now faster than the transpiled Babel
code, it goes from

  templateStringTagES5: 4552 ms.
  templateStringTagES6: 14185 ms.
  templateStringTagBabel: 7626 ms.

to

  templateStringTagES5: 4515 ms.
  templateStringTagES6: 7491 ms.
  templateStringTagBabel: 7639 ms.

which corresponds to a solid 45% reduction in execution time. With some
further optimizations the ES6 version should be able to outperform the
ES5 version. This micro-benchmark should be fairly representative of the
six-speed-templatestringtag-es6 benchmark, and as such that benchmark
should also improve by around 50%.

Bug: v8:6819,v8:6820
Tbr: mlippautz@chromium.org
Change-Id: I821085e3794717fc7f52b5c306fcb93ba03345dc
Reviewed-on: https://chromium-review.googlesource.com/677462Reviewed-by: 's avatarMythri Alle <mythria@chromium.org>
Reviewed-by: 's avatarCaitlin Potter <caitp@igalia.com>
Reviewed-by: 's avatarAdam Klein <adamk@chromium.org>
Reviewed-by: 's avatarBenedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48126}
      79ac69b8
  25. 30 Aug, 2017 1 commit
    • Adam Klein's avatar
      [ast] Make CaseClause a plain ZoneObject, not an Expression · de046f5f
      Adam Klein authored 
      CaseClause never made sense as an Expression; this CL allows us to
remove several UNREACHABLEs and slim down the representation of
CaseClause by removing its source position (which was only used
in prettyprinting).

The only real fallout of this change is that SourceRangeMap now
stores its keys as ZoneObject*, rather than AstNode*, but since
there's already compile time typechecking for inserting items
into the map this shouldn't cause any ill effects.

While modifying CaseClause, also removed the dead body_target()
accessor (and related member variable). Thus this CL overall
reduces the memory needed for each CaseClause by two words.

Bug: v8:6092
Change-Id: I0021c0590a69e29305c41ec6105c8824ae0cc25b
Reviewed-on: https://chromium-review.googlesource.com/639316Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
Reviewed-by: 's avatarMarja Hölttä <marja@chromium.org>
Reviewed-by: 's avatarMythri Alle <mythria@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47722}
      de046f5f
  27. 16 Aug, 2017 1 commit
  29. 01 Aug, 2017 1 commit
    • Sathya Gunasekaran's avatar
      [parser] Provide better error when destructuring callable · c805d5e3
      Sathya Gunasekaran authored 
      The patch changes CallPrinter's AST traversal to continue even after
the first positive match for an AST node. This helps us check for the
subsequent GetIterator AST node in case of destructuring.

We can not differentiate between the function call failing and the
GetIterator failing based on source position info. This would involve
runtime checks costing performance.

Instead of providing an incorrect error, we provide both the
possiblities to user and allow them to disambiguate.

Previously,
  d8> function f() { return 5; }
  undefined
  d8> var [a] = f();
  (d8):1: TypeError: f is not a function
  var [a] = f();
            ^
  TypeError: f is not a function
      at (d8):1:11


Now,
  d8> function f() { return 5; }
  undefined
  d8> var [a] = f();
  (d8):1: TypeError: f is not a function or its return value is not iterable
  var [a] = f();
            ^
  TypeError: f is not a function or its return value is not iterable
      at (d8):1:11

Bug: v8:6616, v8:6513
Change-Id: I3d6427f10cae54951b0ad0e5ddcbe802bb7191c1
Reviewed-on: https://chromium-review.googlesource.com/594894
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: 's avatarAdam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47025}
      c805d5e3
  31. 14 Jul, 2017 3 commits
    • Caitlin Potter's avatar
      [generators] remove SuspendFlags enum and related code · 53553f5d
      Caitlin Potter authored 
      SuspendFlags was originally used by the suspend operation to determine
which field to record the bytecode offset of a suspended generator, and
the value the generator was resumed with. For async generators, await
operations would use a separate field, in order to preserve the previous
yield input value. This was important to ensure `function.sent`
continued to function correctly.

As function.sent is being retired, this allows the removal of support
for that. Given that this was the only real need for SuspendFlags in the
first place (with other uses tacked on as a hack), this involves several
other changes as well:

- Modification of MacroAssembler AssertGeneratorObject. No longer
  accepts a SuspendFlags parameter to determine which type of check to
  perform.
- Removal of `flags` operand from SuspendGenerator bytecode, and the
  GeneratorStore js-operator.
- Removal of `flags` parameter from ResumeGeneratorTrampoline builtins.
- Removal of Runtime functions, interpreter intrinsics and
  AccessBuilders associated with the [[await_input_or_debug_pos]] field
  in JSAsyncGeneratorObject, as this field no longer exists.
- Addition of a new `Yield` AST node (subclass of Suspend) in order to
  prevent the need for the other SuspendFlag values.

BUG=v8:5855
TBR=bmeurer@chromium.org

Change-Id: Iff2881e4742497fe5b774915e988c3d9d8fbe487
Reviewed-on: https://chromium-review.googlesource.com/570485
Commit-Queue: Caitlin Potter <caitp@igalia.com>
Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46683}
      53553f5d
    • Michael Starzinger's avatar
      [ast] Actually print the try-block in AstPrinter. · afdb0b45
      Michael Starzinger authored 
      This fixes a refactoring bug in the AstPrinter to actually print the
try-block of {TryCatchStatement} and {TryFinallyStatement} nodes.

R=neis@chromium.org

Change-Id: I6448251c1eed3f85100902592a76dc7d3a614334
Reviewed-on: https://chromium-review.googlesource.com/571748Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46670}
      afdb0b45
    • Caitlin Potter's avatar
      [async-await] desugar Await in BytecodeGenerator · 8b5b444a
      Caitlin Potter authored 
      This includes several changes. From most to least interesting:

- No longer implement AwaitExpressions using a do-expression.
- Reduces frame-size of async generators by not allocating temporary
  variables to hold results of Await epxressions.
- Streamline and reduce generated bytecodes for Await.
- Debugger no longer emits a debug::kCallBreakLocation breakpoint for
the JS-builtin call performed for Await, and instead only emits such
a breakpoint if the operand of Await is actually a call.
- Push fewer parameters to Await* builtins, using the receiver for the
  first parameter (possible now that the CallRuntime invocation not
  part of the AST).
- Adds a new Await AST node. No new members or anything, but it seemed
  palatable to avoid having `if (is_await())` in a number of
  VisitSuspend functions.

BUG=v8:5855, v8:5099, v8:4483
R=rmcilroy@chromium.org, kozyatinskiy@chromium.org, yangguo@chromium.org
TBR=bmeurer@chromium.org

Change-Id: I9cd3fda99cd40295c04fdf1aea01b5d83fac6caf
Reviewed-on: https://chromium-review.googlesource.com/558806
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
Reviewed-by: 's avatarTobias Tebbi <tebbi@chromium.org>
Reviewed-by: 's avatarAleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46666}
      8b5b444a
  33. 13 Jul, 2017 1 commit
  35. 10 Jul, 2017 1 commit
  37. 06 Jul, 2017 1 commit
  39. 05 Jul, 2017 1 commit
  41. 23 Jun, 2017 1 commit
  43. 06 Jun, 2017 1 commit
    • Igor Sheludko's avatar
      [parser] Introduce SharedFunctionInfo::has_shared_name(). · 9a2c18f5
      Igor Sheludko authored 
      Properly propagate the fact that the function has a statically known name from
parser to SharedFunctionInfo objects. The empty string that has been set as
name before this CL does not help to distinguish cases like:
  var o1 = { ''(){} };
  var o1 = { [foo()](){} };
or
  var o2 = { get ''(){} };
  var o2 = { get [foo()](){} };

This is a preliminary step for using different layouts for closure objects with
and without computed names.

TBR=bmeurer@chromium.org, marja@chromium.org

Bug: v8:6459
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I10afa6f4bda7881c3714711a75f720f83c1d875d
Reviewed-on: https://chromium-review.googlesource.com/522073
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
Reviewed-by: 's avatarToon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45744}
      9a2c18f5
  45. 11 Apr, 2017 2 commits
    • gsathya's avatar
      [ESNext] Implement DynamicImportCall · 94283dcf
      gsathya authored 
      This patch implements the runtime semantics of dynamic import.

We create a new ASTNode so that we can pass the JSFunction closure() to
the runtime function from which we get the script_url.

d8 implements the embedder logic required to load and evaluate the modules.

The API is mostly implemented as specified.

BUG=8:5785

Review-Url: https://codereview.chromium.org/2703563002
Cr-Commit-Position: refs/heads/master@{#44551}
      94283dcf
    • Caitlin Potter's avatar
      [prettyprinter] improve call-printing of GetIterator nodes · b086856f
      Caitlin Potter authored 
      Fix error message printed by Runtime_ThrowCalledNonCallable.

As noted on the bug, this has a slight problem in that it will always
print that "asyncIterator" was not callable for GetIterator with an
async IteratorType, though it may be referring to a different call.
This issue is present regardless of the change I introduced to perform
this desugaring in the BytecodeGenerator.

BUG=v8:6187
R=adamk@chromium.org, verwaest@chromium.org

Change-Id: I2077b7cd5976d9d9ba044f0dff44ee8c312d1263
Reviewed-on: https://chromium-review.googlesource.com/470806Reviewed-by: 's avatarAdam Klein <adamk@chromium.org>
Commit-Queue: Caitlin Potter <caitp@igalia.com>
Cr-Commit-Position: refs/heads/master@{#44543}
      b086856f
  47. 05 Apr, 2017 1 commit
  49. 04 Apr, 2017 1 commit
  51. 31 Mar, 2017 1 commit
  53. 22 Mar, 2017 1 commit
  55. 03 Mar, 2017 1 commit
  57. 07 Feb, 2017 1 commit
  59. 30 Jan, 2017 1 commit
    • mvstanton's avatar
      [TypeFeedbackVector] Combine the literals array and the feedback vector. · 93f05b64
      mvstanton authored 
      They have the same lifetime. It's a match!

Both structures are native context dependent and dealt with (creation,
clearing, gathering feedback) at the same time. By treating the spaces used
for literal boilerplates as feedback vector slots, we no longer have to keep
track of the materialized literal count elsewhere.

A follow-on CL removes even more parser infrastructure related to this count.

BUG=v8:5456

Review-Url: https://codereview.chromium.org/2655853010
Cr-Commit-Position: refs/heads/master@{#42771}
      93f05b64
  61. 09 Jan, 2017 1 commit
  63. 05 Jan, 2017 1 commit
    • gsathya's avatar
      [ESnext] Implement Object spread · a40b7172
      gsathya authored 
      This patch adds parsing of spread object property.

-- Changes ParsePropertyName to parse Token::ELLIPSIS.
-- Throws if rest is encountered by setting a pattern error.
-- Adds a new PropertyKind enum (SPREAD)
-- Adds a new ObjectLiteralProperty::kind (SPREAD)
-- Adds a new harmony-object-spread flag and protects the parser code
with it.
-- Adds a new runtime function called CopyDataProperties
-- Does not add any support for this feature in fullcodegen.
-- Ignition calls out to a runtime function CopyDataProperties to
perform spread operation.
-- Move FastAssign from builtins-objects.cc to objects.cc
-- Refactor Builtin_ObjectAssign to use SetOrCopyDataProperties

Object rest will be implemented in a follow on patch.

BUG=v8:5549

Review-Url: https://codereview.chromium.org/2606833002
Cr-Commit-Position: refs/heads/master@{#42102}
      a40b7172
  65. 19 Dec, 2016 3 commits