1. 05 Sep, 2018 1 commit
    • Hai Dang's avatar
      Reland "[interpreter] Add bytecode for leading array spreads." · 5f8a4272
      Hai Dang authored
      This is a reland of 1c48d52b.
      
      It turned out that IterableToList doesn't always behave according to
      the ES operation with the same name. Specifically, it allows holey arrays
      to take its fast path, which produces an output array with holes where
      actually "undefined" elements should appear.
      
      This CL changes the version of IterableToList that is used for spreads
      (IterableToListWithSymbolLookup) such that holey arrays take the slow path.
      It also includes tests for such situations.
      
      Original change's description:
      > [interpreter] Add bytecode for leading array spreads.
      >
      > This CL improves the performance of creating [...a, b] or [...a].
      > If the array literal has a leading spread, this CL emits the bytecode
      > [CreateArrayFromIterable] to create the literal. CreateArrayFromIterable
      > is implemented by [IterableToListDefault] builtin to create the initial
      > array for the leading spread. IterableToListDefault has a fast path to
      > clone efficiently if the spread is an actual array.
      >
      > The bytecode generated is now shorter. Bytecode generation is refactored
      > into to BuildCreateArrayLiteral, which allows VisitCallSuper to benefit
      > from this optimization also.
      > For now, turbofan also lowers the bytecode to the builtin.
      >
      > The idiomatic use of [...a] to clone the array a now performs better
      > than a simple for-loop, but still does not match the performance of slice.
      >
      > Bug: v8:7980
      >
      > Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
      > Change-Id: Ibde659c82d3c7aa1b1777a3d2f6426ac8cc15e35
      > Reviewed-on: https://chromium-review.googlesource.com/1181024
      > Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
      > Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
      > Reviewed-by: Jakob Gruber <jgruber@chromium.org>
      > Reviewed-by: Georg Neis <neis@chromium.org>
      > Commit-Queue: Georg Neis <neis@chromium.org>
      > Commit-Queue: Hai Dang <dhai@google.com>
      > Cr-Commit-Position: refs/heads/master@{#55520}
      
      Bug: v8:7980
      Change-Id: I0b5603a12d2b588327658bf0a9b214bd0f22e237
      Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
      Reviewed-on: https://chromium-review.googlesource.com/1201882
      Commit-Queue: Hai Dang <dhai@google.com>
      Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
      Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
      Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
      Cr-Commit-Position: refs/heads/master@{#55639}
      5f8a4272
  2. 31 Aug, 2018 1 commit
    • Georg Neis's avatar
      Revert "[interpreter] Add bytecode for leading array spreads." · ef569028
      Georg Neis authored
      This reverts commit 1c48d52b.
      
      Reason for revert: Clusterfuzz found something.
      
      Original change's description:
      > [interpreter] Add bytecode for leading array spreads.
      > 
      > This CL improves the performance of creating [...a, b] or [...a].
      > If the array literal has a leading spread, this CL emits the bytecode
      > [CreateArrayFromIterable] to create the literal. CreateArrayFromIterable
      > is implemented by [IterableToListDefault] builtin to create the initial
      > array for the leading spread. IterableToListDefault has a fast path to
      > clone efficiently if the spread is an actual array.
      > 
      > The bytecode generated is now shorter. Bytecode generation is refactored
      > into to BuildCreateArrayLiteral, which allows VisitCallSuper to benefit
      > from this optimization also.
      > For now, turbofan also lowers the bytecode to the builtin.
      > 
      > The idiomatic use of [...a] to clone the array a now performs better
      > than a simple for-loop, but still does not match the performance of slice.
      > 
      > Bug: v8:7980
      > 
      > Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
      > Change-Id: Ibde659c82d3c7aa1b1777a3d2f6426ac8cc15e35
      > Reviewed-on: https://chromium-review.googlesource.com/1181024
      > Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
      > Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
      > Reviewed-by: Jakob Gruber <jgruber@chromium.org>
      > Reviewed-by: Georg Neis <neis@chromium.org>
      > Commit-Queue: Georg Neis <neis@chromium.org>
      > Commit-Queue: Hai Dang <dhai@google.com>
      > Cr-Commit-Position: refs/heads/master@{#55520}
      
      TBR=rmcilroy@chromium.org,neis@chromium.org,sigurds@chromium.org,gsathya@chromium.org,jgruber@chromium.org,dhai@google.com
      
      Change-Id: I1c86ddcc24274da9f5a8dd3d8bf8d869cbb55cb6
      No-Presubmit: true
      No-Tree-Checks: true
      No-Try: true
      Bug: v8:7980
      Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
      Reviewed-on: https://chromium-review.googlesource.com/1199303Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
      Commit-Queue: Georg Neis <neis@chromium.org>
      Cr-Commit-Position: refs/heads/master@{#55544}
      ef569028
  3. 30 Aug, 2018 1 commit
    • Hai Dang's avatar
      [interpreter] Add bytecode for leading array spreads. · 1c48d52b
      Hai Dang authored
      This CL improves the performance of creating [...a, b] or [...a].
      If the array literal has a leading spread, this CL emits the bytecode
      [CreateArrayFromIterable] to create the literal. CreateArrayFromIterable
      is implemented by [IterableToListDefault] builtin to create the initial
      array for the leading spread. IterableToListDefault has a fast path to
      clone efficiently if the spread is an actual array.
      
      The bytecode generated is now shorter. Bytecode generation is refactored
      into to BuildCreateArrayLiteral, which allows VisitCallSuper to benefit
      from this optimization also.
      For now, turbofan also lowers the bytecode to the builtin.
      
      The idiomatic use of [...a] to clone the array a now performs better
      than a simple for-loop, but still does not match the performance of slice.
      
      Bug: v8:7980
      
      Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
      Change-Id: Ibde659c82d3c7aa1b1777a3d2f6426ac8cc15e35
      Reviewed-on: https://chromium-review.googlesource.com/1181024Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
      Reviewed-by: 's avatarSigurd Schneider <sigurds@chromium.org>
      Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
      Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
      Commit-Queue: Georg Neis <neis@chromium.org>
      Commit-Queue: Hai Dang <dhai@google.com>
      Cr-Commit-Position: refs/heads/master@{#55520}
      1c48d52b
  4. 05 Jul, 2018 1 commit
  5. 04 Jul, 2018 2 commits
  6. 02 Jul, 2018 1 commit
  7. 21 Jun, 2018 1 commit
  8. 29 May, 2018 1 commit
  9. 28 May, 2018 1 commit
  10. 14 May, 2018 1 commit
  11. 05 Apr, 2018 1 commit
  12. 12 Feb, 2018 1 commit
    • Caitlin Potter's avatar
      [esnext] implement spec change to TaggedTemplate callsite caching · d3ca0d00
      Caitlin Potter authored
      Implements the change outlined in https://github.com/tc39/ecma262/pull/890,
      which has been ratified and pulled into the specification. In particular,
      template callsite objects are no longer kept in a global, eternal Map, but
      are instead associated with their callsite, which can be collected. This
      prevents a memory leak incurred by TaggedTemplate calls.
      
      Changes, summarized:
      
          - Remove the TemplateMap and TemplateMapShape objects, instead caching
            template objects in the feedback vector.
          - Remove the `hash` member of TemplateObjectDescriptor, and the Equals
            method (used by TemplateMap)
          - Add a new FeedbackSlotKind (kTemplateObject), which behaves similarly
            to FeedbackSlotKind::kLiteral, but prevents eval caching. This ensures
            that a new feedback vector is always created for eval() containing tagged
            templates, even when the CompilationCache is used.
          - GetTemplateObject bytecode now takes a feedback index, and only calls
            into the runtime if the feedback is Smi::kZero (uninitialized).
      
      BUG=v8:3230, v8:2891
      R=littledan@chromium.org, yangguo@chromium.org, bmeurer@chromium.org,
      rmcilroy@chromium.org
      
      Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
      Change-Id: I7827bc148d3d93e2b056ebf63dd624da196ad423
      Reviewed-on: https://chromium-review.googlesource.com/624564
      Commit-Queue: Caitlin Potter <caitp@igalia.com>
      Reviewed-by: 's avatarBenedikt Meurer <bmeurer@chromium.org>
      Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
      Cr-Commit-Position: refs/heads/master@{#51248}
      d3ca0d00
  13. 29 Jan, 2018 1 commit
  14. 11 Jan, 2018 1 commit
    • Caitlin Potter's avatar
      Reland "[esnext] load `iterator.next` only once at beginning of iteration" · 2d889aa9
      Caitlin Potter authored
      https://github.com/tc39/ecma262/pull/988 gained concensus during the
      september 2017 TC39 meetings. This moves the load of the "next" method
      to the very beginning of the iteration protocol, rather than during
      each iteration step.
      
      This impacts:
      
      - yield*
      - for-of loops
      - spread arguments
      - array spreads
      
      In the v8 implementation, this also affects async iteration versions of
      these things (the sole exception being the Async-From-Sync iterator,
      which requires a few more changes to work with this, likely done in a
      followup patch).
      
      This change introduces a new AST node, ResolvedProperty, which can be used
      as a callee by Call nodes to produce the same bytecode as Property calls,
      without observably re-loading the property. This is used in several
      AST-desugarings involving the iteration protocol.
      
      BUG=v8:6861, v8:5699
      R=rmcilroy@chromium.org
      TBR=neis@chromium.org, adamk@chromium.org
      
      Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
      Change-Id: I9685db6e85315ba8a2df87a4537c2bf491e1e35b
      Reviewed-on: https://chromium-review.googlesource.com/857593
      Commit-Queue: Caitlin Potter <caitp@igalia.com>
      Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
      Cr-Commit-Position: refs/heads/master@{#50518}
      2d889aa9
  15. 09 Jan, 2018 2 commits
    • Michael Achenbach's avatar
      Revert "[esnext] load `iterator.next` only once at beginning of iteration" · 163b5d70
      Michael Achenbach authored
      This reverts commit bf4cc9ee.
      
      Reason for revert: Breaks windows with msvc and linux with gcc
      https://build.chromium.org/p/client.v8/builders/V8%20Win64%20-%20msvc/builds/841
      https://build.chromium.org/p/client.v8/builders/V8%20Linux%20gcc%204.8/builds/17265
      
      Original change's description:
      > [esnext] load `iterator.next` only once at beginning of iteration
      > 
      > https://github.com/tc39/ecma262/pull/988 gained concensus during the
      > september 2017 TC39 meetings. This moves the load of the "next" method
      > to the very beginning of the iteration protocol, rather than during
      > each iteration step.
      > 
      > This impacts:
      > 
      > - yield*
      > - for-of loops
      > - spread arguments
      > - array spreads
      > 
      > In the v8 implementation, this also affects async iteration versions of
      > these things (the sole exception being the Async-From-Sync iterator,
      > which requires a few more changes to work with this, likely done in a
      > followup patch).
      > 
      > This change introduces a new AST node, ResolvedProperty, which can be used
      > as a callee by Call nodes to produce the same bytecode as Property calls,
      > without observably re-loading the property. This is used in several
      > AST-desugarings involving the iteration protocol.
      > 
      > BUG=v8:6861, v8:5699
      > R=​rmcilroy@chromium.org, neis@chromium.org, adamk@chromium.org
      > 
      > Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
      > Change-Id: Ib81106a0182687fc5efea0bc32302ad06376773b
      > Reviewed-on: https://chromium-review.googlesource.com/687997
      > Commit-Queue: Caitlin Potter <caitp@igalia.com>
      > Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
      > Reviewed-by: Adam Klein <adamk@chromium.org>
      > Reviewed-by: Georg Neis <neis@chromium.org>
      > Cr-Commit-Position: refs/heads/master@{#50452}
      
      TBR=rmcilroy@chromium.org,adamk@chromium.org,neis@chromium.org,caitp@igalia.com,caitp@chromium.org
      
      Change-Id: I1797c0d596dfd6850d6f0f505f591a7a990dd1f1
      No-Presubmit: true
      No-Tree-Checks: true
      No-Try: true
      Bug: v8:6861, v8:5699
      Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
      Reviewed-on: https://chromium-review.googlesource.com/857616Reviewed-by: 's avatarMichael Achenbach <machenbach@chromium.org>
      Commit-Queue: Michael Achenbach <machenbach@chromium.org>
      Cr-Commit-Position: refs/heads/master@{#50454}
      163b5d70
    • Caitlin Potter's avatar
      [esnext] load `iterator.next` only once at beginning of iteration · bf4cc9ee
      Caitlin Potter authored
      https://github.com/tc39/ecma262/pull/988 gained concensus during the
      september 2017 TC39 meetings. This moves the load of the "next" method
      to the very beginning of the iteration protocol, rather than during
      each iteration step.
      
      This impacts:
      
      - yield*
      - for-of loops
      - spread arguments
      - array spreads
      
      In the v8 implementation, this also affects async iteration versions of
      these things (the sole exception being the Async-From-Sync iterator,
      which requires a few more changes to work with this, likely done in a
      followup patch).
      
      This change introduces a new AST node, ResolvedProperty, which can be used
      as a callee by Call nodes to produce the same bytecode as Property calls,
      without observably re-loading the property. This is used in several
      AST-desugarings involving the iteration protocol.
      
      BUG=v8:6861, v8:5699
      R=rmcilroy@chromium.org, neis@chromium.org, adamk@chromium.org
      
      Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
      Change-Id: Ib81106a0182687fc5efea0bc32302ad06376773b
      Reviewed-on: https://chromium-review.googlesource.com/687997
      Commit-Queue: Caitlin Potter <caitp@igalia.com>
      Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
      Reviewed-by: 's avatarAdam Klein <adamk@chromium.org>
      Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
      Cr-Commit-Position: refs/heads/master@{#50452}
      bf4cc9ee
  16. 18 Dec, 2017 1 commit
  17. 15 Dec, 2017 1 commit
  18. 17 Nov, 2017 1 commit
  19. 10 Nov, 2017 2 commits
  20. 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
  21. 08 Nov, 2017 1 commit
  22. 03 Nov, 2017 3 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
    • Sathya Gunasekaran's avatar
      [class] Evaluate static computed props during class definition · 4f781eca
      Sathya Gunasekaran authored
      This patch evaluates computed properties in the order of declaration
      during class definition time.
      
      This patch creates a synthetic variable to store the result of
      evaluating a computed property and then looks this up in the
      initializer function.
      
      Bug: v8:5367
      Change-Id: I4182c6a01196d2538991818142890f6afb0e532b
      Reviewed-on: https://chromium-review.googlesource.com/752567Reviewed-by: 's avatarMythri Alle <mythria@chromium.org>
      Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
      Reviewed-by: 's avatarAdam Klein <adamk@chromium.org>
      Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
      Cr-Commit-Position: refs/heads/master@{#49115}
      4f781eca
  23. 31 Oct, 2017 4 commits
  24. 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
  25. 25 Oct, 2017 1 commit
  26. 24 Oct, 2017 1 commit
  27. 19 Oct, 2017 1 commit
  28. 13 Oct, 2017 1 commit
  29. 10 Oct, 2017 1 commit
  30. 25 Sep, 2017 1 commit
    • Benedikt Meurer's avatar
      [turbofan] Properly optimize literals in inlined functions. · 855b88ae
      Benedikt Meurer authored
      When inlining based on SharedFunctionInfo rather than based on concrete
      JSFunction, we weren't able to properly optimize array, object and
      regexp literals inside the inlinee, because we didn't know the concrete
      FeedbackVector for the inlinee inside JSCreateLowering. This was because
      JSCreateLowering wasn't properly updated after the literals moved to the
      FeedbackVector. Now with this CL we also have the VectorSlotPair on the
      literal creation operators, just like we do for property accesses and
      calls, and are thus able to always access the appropriate FeedbackVector
      and optimize the literal creation.
      
      The impact is illustrated by the micro-benchmark on the tracking bug,
      which goes from
      
        createEmptyArrayLiteral: 1846 ms.
        createShallowArrayLiteral: 1868 ms.
        createShallowObjectLiteral: 2246 ms.
      
      to
      
        createEmptyArrayLiteral: 1175 ms.
        createShallowArrayLiteral: 1187 ms.
        createShallowObjectLiteral: 1195 ms.
      
      with this CL, so up to 2x faster now.
      
      Drive-by-fix: Also remove the unused CreateEmptyObjectLiteral builtin
      and cleanup the names of the other builtins to be consistent with the
      names of the TurboFan operators and Ignition bytecodes.
      
      Bug: v8:6856
      Change-Id: I453828d019b27c9aa1344edac0dd84e91a457097
      Reviewed-on: https://chromium-review.googlesource.com/680656
      Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
      Reviewed-by: 's avatarYang Guo <yangguo@chromium.org>
      Cr-Commit-Position: refs/heads/master@{#48140}
      855b88ae
  31. 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
  32. 18 Sep, 2017 1 commit