v8/src/deoptimize-reason.h

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// Copyright 2016 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef V8_DEOPTIMIZE_REASON_H_
#define V8_DEOPTIMIZE_REASON_H_
#include "src/globals.h"
namespace v8 {
namespace internal {
[turbofan] Optimize O.p.hasOwnProperty inside for-in. Optimize the common pattern for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { // do something } } which is part of the guard-for-in style in ESLint (see the documentation at https://eslint.org/docs/rules/guard-for-in for details). This pattern also shows up in React and Ember applications quite a lot (and is tested by the appropriate Speedometer benchmarks, although not dominating those benchmarks, since they spent a lot of time in non-TurboFan'ed code). This improves the forInHasOwnProperty and forInHasOwnPropertySafe micro- benchmarks in v8:6702, which look like this function forInHasOwnProperty(o) { var result = 0; for (var i in o) { if (o.hasOwnProperty(i)) { result += 1; } } return result; } function forInHasOwnPropertySafe(o) { var result = 0; for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { result += 1; } } return result; } by around 4x and allows for additional optimizations in the future, by also elimiating the megamorphic load when accessing the enumerated properties. This changes the interpreter ForInNext bytecode to collect more precise feedback about the for-in state, which now consists of three individual states: UNINITIALIZED, MEGAMORPHIC and GENERIC. The MEGAMORPHIC state means that the ForInNext has only seen objects with a usable enum cache thus far, whereas GENERIC means that we have seen some slow-mode for..in objects as well. R=jarin@chromium.org Bug: v8:6702 Change-Id: Ibcd75ea9b58c3b4f9219f11bc37eb04a2b985604 Reviewed-on: https://chromium-review.googlesource.com/636964 Commit-Queue: Benedikt Meurer <bmeurer@chromium.org> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org> Cr-Commit-Position: refs/heads/master@{#47632}
2017-08-28 05:26:15 +00:00
#define DEOPTIMIZE_REASON_LIST(V) \
V(ArrayBufferWasDetached, "array buffer was detached") \
V(CowArrayElementsChanged, "copy-on-write array's elements changed") \
V(CouldNotGrowElements, "failed to grow elements store") \
V(DeoptimizeNow, "%_DeoptimizeNow") \
[turbofan] Optimize O.p.hasOwnProperty inside for-in. Optimize the common pattern for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { // do something } } which is part of the guard-for-in style in ESLint (see the documentation at https://eslint.org/docs/rules/guard-for-in for details). This pattern also shows up in React and Ember applications quite a lot (and is tested by the appropriate Speedometer benchmarks, although not dominating those benchmarks, since they spent a lot of time in non-TurboFan'ed code). This improves the forInHasOwnProperty and forInHasOwnPropertySafe micro- benchmarks in v8:6702, which look like this function forInHasOwnProperty(o) { var result = 0; for (var i in o) { if (o.hasOwnProperty(i)) { result += 1; } } return result; } function forInHasOwnPropertySafe(o) { var result = 0; for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { result += 1; } } return result; } by around 4x and allows for additional optimizations in the future, by also elimiating the megamorphic load when accessing the enumerated properties. This changes the interpreter ForInNext bytecode to collect more precise feedback about the for-in state, which now consists of three individual states: UNINITIALIZED, MEGAMORPHIC and GENERIC. The MEGAMORPHIC state means that the ForInNext has only seen objects with a usable enum cache thus far, whereas GENERIC means that we have seen some slow-mode for..in objects as well. R=jarin@chromium.org Bug: v8:6702 Change-Id: Ibcd75ea9b58c3b4f9219f11bc37eb04a2b985604 Reviewed-on: https://chromium-review.googlesource.com/636964 Commit-Queue: Benedikt Meurer <bmeurer@chromium.org> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org> Cr-Commit-Position: refs/heads/master@{#47632}
2017-08-28 05:26:15 +00:00
V(DivisionByZero, "division by zero") \
V(Hole, "hole") \
V(InstanceMigrationFailed, "instance migration failed") \
V(InsufficientTypeFeedbackForCall, "Insufficient type feedback for call") \
V(InsufficientTypeFeedbackForConstruct, \
"Insufficient type feedback for construct") \
V(InsufficientTypeFeedbackForForIn, "Insufficient type feedback for for-in") \
V(InsufficientTypeFeedbackForBinaryOperation, \
"Insufficient type feedback for binary operation") \
V(InsufficientTypeFeedbackForCompareOperation, \
"Insufficient type feedback for compare operation") \
[turbofan] Optimize O.p.hasOwnProperty inside for-in. Optimize the common pattern for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { // do something } } which is part of the guard-for-in style in ESLint (see the documentation at https://eslint.org/docs/rules/guard-for-in for details). This pattern also shows up in React and Ember applications quite a lot (and is tested by the appropriate Speedometer benchmarks, although not dominating those benchmarks, since they spent a lot of time in non-TurboFan'ed code). This improves the forInHasOwnProperty and forInHasOwnPropertySafe micro- benchmarks in v8:6702, which look like this function forInHasOwnProperty(o) { var result = 0; for (var i in o) { if (o.hasOwnProperty(i)) { result += 1; } } return result; } function forInHasOwnPropertySafe(o) { var result = 0; for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { result += 1; } } return result; } by around 4x and allows for additional optimizations in the future, by also elimiating the megamorphic load when accessing the enumerated properties. This changes the interpreter ForInNext bytecode to collect more precise feedback about the for-in state, which now consists of three individual states: UNINITIALIZED, MEGAMORPHIC and GENERIC. The MEGAMORPHIC state means that the ForInNext has only seen objects with a usable enum cache thus far, whereas GENERIC means that we have seen some slow-mode for..in objects as well. R=jarin@chromium.org Bug: v8:6702 Change-Id: Ibcd75ea9b58c3b4f9219f11bc37eb04a2b985604 Reviewed-on: https://chromium-review.googlesource.com/636964 Commit-Queue: Benedikt Meurer <bmeurer@chromium.org> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org> Cr-Commit-Position: refs/heads/master@{#47632}
2017-08-28 05:26:15 +00:00
V(InsufficientTypeFeedbackForGenericNamedAccess, \
"Insufficient type feedback for generic named access") \
V(InsufficientTypeFeedbackForGenericKeyedAccess, \
"Insufficient type feedback for generic keyed access") \
V(InsufficientTypeFeedbackForUnaryOperation, \
"Insufficient type feedback for unary operation") \
[turbofan] Optimize O.p.hasOwnProperty inside for-in. Optimize the common pattern for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { // do something } } which is part of the guard-for-in style in ESLint (see the documentation at https://eslint.org/docs/rules/guard-for-in for details). This pattern also shows up in React and Ember applications quite a lot (and is tested by the appropriate Speedometer benchmarks, although not dominating those benchmarks, since they spent a lot of time in non-TurboFan'ed code). This improves the forInHasOwnProperty and forInHasOwnPropertySafe micro- benchmarks in v8:6702, which look like this function forInHasOwnProperty(o) { var result = 0; for (var i in o) { if (o.hasOwnProperty(i)) { result += 1; } } return result; } function forInHasOwnPropertySafe(o) { var result = 0; for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { result += 1; } } return result; } by around 4x and allows for additional optimizations in the future, by also elimiating the megamorphic load when accessing the enumerated properties. This changes the interpreter ForInNext bytecode to collect more precise feedback about the for-in state, which now consists of three individual states: UNINITIALIZED, MEGAMORPHIC and GENERIC. The MEGAMORPHIC state means that the ForInNext has only seen objects with a usable enum cache thus far, whereas GENERIC means that we have seen some slow-mode for..in objects as well. R=jarin@chromium.org Bug: v8:6702 Change-Id: Ibcd75ea9b58c3b4f9219f11bc37eb04a2b985604 Reviewed-on: https://chromium-review.googlesource.com/636964 Commit-Queue: Benedikt Meurer <bmeurer@chromium.org> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org> Cr-Commit-Position: refs/heads/master@{#47632}
2017-08-28 05:26:15 +00:00
V(LostPrecision, "lost precision") \
V(LostPrecisionOrNaN, "lost precision or NaN") \
V(MinusZero, "minus zero") \
V(NaN, "NaN") \
V(NoCache, "no cache") \
V(NotAHeapNumber, "not a heap number") \
V(NotAJavaScriptObject, "not a JavaScript object") \
[turbofan] ReceiverOrNullOrUndefined feedback for JSEqual. This changes the ReceiverOrOddball feedback on JSStrictEqual to ReceiverOrNullOrUndefined feedback, which can also safely be consumed by JSEqual (we cannot generally accept any oddball here since booleans trigger implicit conversions, unfortunately). Thus we replace the previously introduced CheckReceiverOrOddball with CheckReceiverOrNullOrUndefined, and drop CheckOddball, since we will no longer collect Oddball feedback separately. TurboFan will then turn a JSEqual[ReceiverOrNullOrUndefined] into a sequence like this: ``` left = CheckReceiverOrNullOrUndefined(left); right = CheckReceiverOrNullOrUndefined(right); result = if ObjectIsUndetectable(left) then ObjectIsUndetectable(right) else ReferenceEqual(left, right); ``` This significantly improves the peak performance of abstract equality with Receiver, Null or Undefined inputs. On the test case outlined in http://crbug.com/v8/8356 we go from naive: 2946 ms. tenary: 2134 ms. to naive: 2230 ms. tenary: 2250 ms. which corresponds to a 25% improvement on the abstract equality case. For regular code this will probably yield more performance, since we get rid of the JSEqual operator, which might have arbitrary side effects and thus blocks all kinds of TurboFan optimizations. The JSStrictEqual case is slightly slower now, since it has to rule out booleans as well (even though that's not strictly necessary, but consistency is key here). This way developers can safely use `a == b` instead of doing a dance like `a == null ? b == null : a === b` (which is what dart2js does right now) when both `a` and `b` are known to be Receiver, Null or Undefined. The abstract equality is not only faster to parse than the tenary, but also generates a shorter bytecode sequence. In the test case referenced in http://crbug.com/v8/8356 the bytecode for `naive` is ``` StackCheck Ldar a1 TestEqual a0, [0] JumpIfFalse [5] LdaSmi [1] Return LdaSmi [2] Return ``` which is 14 bytes, whereas the `tenary` function generates ``` StackCheck Ldar a0 TestUndetectable JumpIfFalse [7] Ldar a1 TestUndetectable Jump [7] Ldar a1 TestEqualStrict a0, [0] JumpIfToBooleanFalse [5] LdaSmi [1] Return LdaSmi [2] Return ``` which is 24 bytes. So the `naive` version is 40% smaller and requires fewer bytecode dispatches. Bug: chromium:898455, v8:8356 Change-Id: If3961b2518b4438700706b3bd6071d546305e233 Reviewed-on: https://chromium-review.googlesource.com/c/1297315 Reviewed-by: Jaroslav Sevcik <jarin@chromium.org> Commit-Queue: Benedikt Meurer <bmeurer@chromium.org> Cr-Commit-Position: refs/heads/master@{#56948}
2018-10-24 12:09:34 +00:00
V(NotAJavaScriptObjectOrNullOrUndefined, \
"not a JavaScript object, Null or Undefined") \
[turbofan] Optimize O.p.hasOwnProperty inside for-in. Optimize the common pattern for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { // do something } } which is part of the guard-for-in style in ESLint (see the documentation at https://eslint.org/docs/rules/guard-for-in for details). This pattern also shows up in React and Ember applications quite a lot (and is tested by the appropriate Speedometer benchmarks, although not dominating those benchmarks, since they spent a lot of time in non-TurboFan'ed code). This improves the forInHasOwnProperty and forInHasOwnPropertySafe micro- benchmarks in v8:6702, which look like this function forInHasOwnProperty(o) { var result = 0; for (var i in o) { if (o.hasOwnProperty(i)) { result += 1; } } return result; } function forInHasOwnPropertySafe(o) { var result = 0; for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { result += 1; } } return result; } by around 4x and allows for additional optimizations in the future, by also elimiating the megamorphic load when accessing the enumerated properties. This changes the interpreter ForInNext bytecode to collect more precise feedback about the for-in state, which now consists of three individual states: UNINITIALIZED, MEGAMORPHIC and GENERIC. The MEGAMORPHIC state means that the ForInNext has only seen objects with a usable enum cache thus far, whereas GENERIC means that we have seen some slow-mode for..in objects as well. R=jarin@chromium.org Bug: v8:6702 Change-Id: Ibcd75ea9b58c3b4f9219f11bc37eb04a2b985604 Reviewed-on: https://chromium-review.googlesource.com/636964 Commit-Queue: Benedikt Meurer <bmeurer@chromium.org> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org> Cr-Commit-Position: refs/heads/master@{#47632}
2017-08-28 05:26:15 +00:00
V(NotANumberOrOddball, "not a Number or Oddball") \
V(NotASmi, "not a Smi") \
V(NotAString, "not a String") \
[turbofan] Optimize O.p.hasOwnProperty inside for-in. Optimize the common pattern for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { // do something } } which is part of the guard-for-in style in ESLint (see the documentation at https://eslint.org/docs/rules/guard-for-in for details). This pattern also shows up in React and Ember applications quite a lot (and is tested by the appropriate Speedometer benchmarks, although not dominating those benchmarks, since they spent a lot of time in non-TurboFan'ed code). This improves the forInHasOwnProperty and forInHasOwnPropertySafe micro- benchmarks in v8:6702, which look like this function forInHasOwnProperty(o) { var result = 0; for (var i in o) { if (o.hasOwnProperty(i)) { result += 1; } } return result; } function forInHasOwnPropertySafe(o) { var result = 0; for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { result += 1; } } return result; } by around 4x and allows for additional optimizations in the future, by also elimiating the megamorphic load when accessing the enumerated properties. This changes the interpreter ForInNext bytecode to collect more precise feedback about the for-in state, which now consists of three individual states: UNINITIALIZED, MEGAMORPHIC and GENERIC. The MEGAMORPHIC state means that the ForInNext has only seen objects with a usable enum cache thus far, whereas GENERIC means that we have seen some slow-mode for..in objects as well. R=jarin@chromium.org Bug: v8:6702 Change-Id: Ibcd75ea9b58c3b4f9219f11bc37eb04a2b985604 Reviewed-on: https://chromium-review.googlesource.com/636964 Commit-Queue: Benedikt Meurer <bmeurer@chromium.org> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org> Cr-Commit-Position: refs/heads/master@{#47632}
2017-08-28 05:26:15 +00:00
V(NotASymbol, "not a Symbol") \
V(OutOfBounds, "out of bounds") \
V(Overflow, "overflow") \
V(ReceiverNotAGlobalProxy, "receiver was not a global proxy") \
[turbofan] Optimize O.p.hasOwnProperty inside for-in. Optimize the common pattern for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { // do something } } which is part of the guard-for-in style in ESLint (see the documentation at https://eslint.org/docs/rules/guard-for-in for details). This pattern also shows up in React and Ember applications quite a lot (and is tested by the appropriate Speedometer benchmarks, although not dominating those benchmarks, since they spent a lot of time in non-TurboFan'ed code). This improves the forInHasOwnProperty and forInHasOwnPropertySafe micro- benchmarks in v8:6702, which look like this function forInHasOwnProperty(o) { var result = 0; for (var i in o) { if (o.hasOwnProperty(i)) { result += 1; } } return result; } function forInHasOwnPropertySafe(o) { var result = 0; for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { result += 1; } } return result; } by around 4x and allows for additional optimizations in the future, by also elimiating the megamorphic load when accessing the enumerated properties. This changes the interpreter ForInNext bytecode to collect more precise feedback about the for-in state, which now consists of three individual states: UNINITIALIZED, MEGAMORPHIC and GENERIC. The MEGAMORPHIC state means that the ForInNext has only seen objects with a usable enum cache thus far, whereas GENERIC means that we have seen some slow-mode for..in objects as well. R=jarin@chromium.org Bug: v8:6702 Change-Id: Ibcd75ea9b58c3b4f9219f11bc37eb04a2b985604 Reviewed-on: https://chromium-review.googlesource.com/636964 Commit-Queue: Benedikt Meurer <bmeurer@chromium.org> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org> Cr-Commit-Position: refs/heads/master@{#47632}
2017-08-28 05:26:15 +00:00
V(Smi, "Smi") \
V(Unknown, "(unknown)") \
[turbofan] Optimize O.p.hasOwnProperty inside for-in. Optimize the common pattern for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { // do something } } which is part of the guard-for-in style in ESLint (see the documentation at https://eslint.org/docs/rules/guard-for-in for details). This pattern also shows up in React and Ember applications quite a lot (and is tested by the appropriate Speedometer benchmarks, although not dominating those benchmarks, since they spent a lot of time in non-TurboFan'ed code). This improves the forInHasOwnProperty and forInHasOwnPropertySafe micro- benchmarks in v8:6702, which look like this function forInHasOwnProperty(o) { var result = 0; for (var i in o) { if (o.hasOwnProperty(i)) { result += 1; } } return result; } function forInHasOwnPropertySafe(o) { var result = 0; for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { result += 1; } } return result; } by around 4x and allows for additional optimizations in the future, by also elimiating the megamorphic load when accessing the enumerated properties. This changes the interpreter ForInNext bytecode to collect more precise feedback about the for-in state, which now consists of three individual states: UNINITIALIZED, MEGAMORPHIC and GENERIC. The MEGAMORPHIC state means that the ForInNext has only seen objects with a usable enum cache thus far, whereas GENERIC means that we have seen some slow-mode for..in objects as well. R=jarin@chromium.org Bug: v8:6702 Change-Id: Ibcd75ea9b58c3b4f9219f11bc37eb04a2b985604 Reviewed-on: https://chromium-review.googlesource.com/636964 Commit-Queue: Benedikt Meurer <bmeurer@chromium.org> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org> Cr-Commit-Position: refs/heads/master@{#47632}
2017-08-28 05:26:15 +00:00
V(ValueMismatch, "value mismatch") \
V(WrongCallTarget, "wrong call target") \
V(WrongEnumIndices, "wrong enum indices") \
[turbofan] Optimize O.p.hasOwnProperty inside for-in. Optimize the common pattern for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { // do something } } which is part of the guard-for-in style in ESLint (see the documentation at https://eslint.org/docs/rules/guard-for-in for details). This pattern also shows up in React and Ember applications quite a lot (and is tested by the appropriate Speedometer benchmarks, although not dominating those benchmarks, since they spent a lot of time in non-TurboFan'ed code). This improves the forInHasOwnProperty and forInHasOwnPropertySafe micro- benchmarks in v8:6702, which look like this function forInHasOwnProperty(o) { var result = 0; for (var i in o) { if (o.hasOwnProperty(i)) { result += 1; } } return result; } function forInHasOwnPropertySafe(o) { var result = 0; for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { result += 1; } } return result; } by around 4x and allows for additional optimizations in the future, by also elimiating the megamorphic load when accessing the enumerated properties. This changes the interpreter ForInNext bytecode to collect more precise feedback about the for-in state, which now consists of three individual states: UNINITIALIZED, MEGAMORPHIC and GENERIC. The MEGAMORPHIC state means that the ForInNext has only seen objects with a usable enum cache thus far, whereas GENERIC means that we have seen some slow-mode for..in objects as well. R=jarin@chromium.org Bug: v8:6702 Change-Id: Ibcd75ea9b58c3b4f9219f11bc37eb04a2b985604 Reviewed-on: https://chromium-review.googlesource.com/636964 Commit-Queue: Benedikt Meurer <bmeurer@chromium.org> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org> Cr-Commit-Position: refs/heads/master@{#47632}
2017-08-28 05:26:15 +00:00
V(WrongInstanceType, "wrong instance type") \
[turbofan] Significantly improve ConsString creation performance. This change significantly improves the performance of string concatenation in optimized code for the case where the resulting string is represented as a ConsString. On the relevant test cases we go from serializeNaive: 10762 ms. serializeClever: 7813 ms. serializeConcat: 10271 ms. to serializeNaive: 10278 ms. serializeClever: 5533 ms. serializeConcat: 10310 ms. which represents a 30% improvement on the "clever" benchmark, which tests specifically the ConsString creation performance. This was accomplished via a couple of different steps, which are briefly outlined here: 1. The empty_string gets its own map, so that we can easily recognize and handle it appropriately in the TurboFan type system. This allows us to express (and assert) that the inputs to NewConsString are non-empty strings, making sure that TurboFan no longer creates "crippled ConsStrings" with empty left or right hand sides. 2. Further split the existing String types in TurboFan to be able to distinguish between OneByte and TwoByte strings on the type system level. This allows us to avoid having to dynamically lookup the resulting ConsString map in case of ConsString creation (i.e. when we know that both input strings are OneByte strings or at least one of the input strings is TwoByte). 3. We also introduced more finegrained feedback for the Add bytecode in the interpreter, having it collect feedback about ConsStrings, specifically ConsOneByteString and ConsTwoByteString. This feedback can be used by TurboFan to only inline the relevant code for what was seen so far. This allows us to remove the Octane/Splay specific magic in JSTypedLowering to detect ConsString creation, and instead purely rely on the feedback of what was seen so far (also making it possible to change the semantics of NewConsString to be a low-level operator, which is only introduced in SimplifiedLowering by looking at the input types of StringConcat). 4. On top of the before mentioned type and interpreter changes we added new operators CheckNonEmptyString, CheckNonEmptyOneByteString, and CheckNonEmptyTwoByteString, which perform the appropriate (dynamic) checks. There are several more improvements that are possible based on this, but since the change was already quite big, we decided not to put everything into the first change, but do some follow up tweaks to the type system, and builtin optimizations later. Tbr: mstarzinger@chromium.org Bug: v8:8834, v8:8931, v8:8939, v8:8951 Change-Id: Ia24e17c6048bf2b04df966d3cd441f0edda05c93 Cq-Include-Trybots: luci.chromium.try:linux-blink-rel Doc: https://bit.ly/fast-string-concatenation-in-javascript Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1499497 Commit-Queue: Michael Achenbach <machenbach@chromium.org> Reviewed-by: Yang Guo <yangguo@chromium.org> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org> Reviewed-by: Mythri Alle <mythria@chromium.org> Reviewed-by: Benedikt Meurer <bmeurer@chromium.org> Cr-Commit-Position: refs/heads/master@{#60318}
2019-03-18 19:33:46 +00:00
V(WrongLength, "wrong length") \
[turbofan] Optimize O.p.hasOwnProperty inside for-in. Optimize the common pattern for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { // do something } } which is part of the guard-for-in style in ESLint (see the documentation at https://eslint.org/docs/rules/guard-for-in for details). This pattern also shows up in React and Ember applications quite a lot (and is tested by the appropriate Speedometer benchmarks, although not dominating those benchmarks, since they spent a lot of time in non-TurboFan'ed code). This improves the forInHasOwnProperty and forInHasOwnPropertySafe micro- benchmarks in v8:6702, which look like this function forInHasOwnProperty(o) { var result = 0; for (var i in o) { if (o.hasOwnProperty(i)) { result += 1; } } return result; } function forInHasOwnPropertySafe(o) { var result = 0; for (var i in o) { if (Object.prototype.hasOwnProperty.call(o, i)) { result += 1; } } return result; } by around 4x and allows for additional optimizations in the future, by also elimiating the megamorphic load when accessing the enumerated properties. This changes the interpreter ForInNext bytecode to collect more precise feedback about the for-in state, which now consists of three individual states: UNINITIALIZED, MEGAMORPHIC and GENERIC. The MEGAMORPHIC state means that the ForInNext has only seen objects with a usable enum cache thus far, whereas GENERIC means that we have seen some slow-mode for..in objects as well. R=jarin@chromium.org Bug: v8:6702 Change-Id: Ibcd75ea9b58c3b4f9219f11bc37eb04a2b985604 Reviewed-on: https://chromium-review.googlesource.com/636964 Commit-Queue: Benedikt Meurer <bmeurer@chromium.org> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org> Cr-Commit-Position: refs/heads/master@{#47632}
2017-08-28 05:26:15 +00:00
V(WrongMap, "wrong map") \
[ic] Ensure that we make progress on KeyedLoadIC polymorphic name. In the special case of KeyedLoadIC, where the key that is passed in is a Name that is always the same we only checked for identity in both the stub and the TurboFan case, which works fine for symbols and internalized strings, but doesn't really work with non-internalized strings, where the identity check will fail, the runtime will internalize the string, and the IC will then see the original internalized string again and not progress in the feedback lattice. This leads to tricky deoptimization loops in TurboFan and constantly missing ICs. This adds fixes the stub to always try to internalize strings first when the identity check fails and then doing the check again. If the name is not found in the string table we miss, since in that case the string cannot match the previously recorded feedback name (which is always a unique name). In TurboFan we represent this checks with new CheckEqualsSymbol and CheckEqualsInternalizedString operators, which validate the previously recorded feedback, and the CheckEqualsInternalizedString operator does the attempt to internalize the input. Bug: v8:6936, v8:6948, v8:6969 Change-Id: I3f3b4a587c67f00f7c4b60d239eb98a9626fe04a Reviewed-on: https://chromium-review.googlesource.com/730224 Reviewed-by: Toon Verwaest <verwaest@chromium.org> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org> Commit-Queue: Benedikt Meurer <bmeurer@chromium.org> Cr-Commit-Position: refs/heads/master@{#48784}
2017-10-20 11:36:26 +00:00
V(WrongName, "wrong name") \
V(WrongValue, "wrong value") \
V(NoInitialElement, "no initial element")
enum class DeoptimizeReason : uint8_t {
#define DEOPTIMIZE_REASON(Name, message) k##Name,
DEOPTIMIZE_REASON_LIST(DEOPTIMIZE_REASON)
#undef DEOPTIMIZE_REASON
};
V8_EXPORT_PRIVATE std::ostream& operator<<(std::ostream&, DeoptimizeReason);
size_t hash_value(DeoptimizeReason reason);
V8_EXPORT_PRIVATE char const* DeoptimizeReasonToString(DeoptimizeReason reason);
} // namespace internal
} // namespace v8
#endif // V8_DEOPTIMIZE_REASON_H_