We translate loads with TaggedXXX (XXX in {"", "Signed", "Pointer"})
representation in CSA into loads of CompressedXXX +
ChangeCompressedXXXToTaggedXXX in the raw-machine-assembler.
This way, CSA doesn't need to know about Compressed values since we
are introducing an explicit "decompress" node.
Also updating tests that were checking for the load nodes.
Cq-Include-Trybots: luci.v8.try:v8_linux64_pointer_compression_rel_ng
Cq-Include-Trybots: luci.v8.try:v8_linux64_arm64_pointer_compression_rel_ng
Bug: v8:8977, v8:7703
Change-Id: Ie22ca8123a25ef005c1ff7383776f9355020fa42
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1565897
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60873}
For macros expanding to function definitions, I removed the spurious ; after
macro invocations. For macros expandign to function declarations, I made the ;
required and consistently inserted it.
No behavior change.
Bug: chromium:926235
Change-Id: Ib8085d85d913d74307e3481f7fee4b7dc78c7549
Reviewed-on: https://chromium-review.googlesource.com/c/1467545
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59558}
This CL is an experiment to get more performance data from the perf-bots
and will likely lead to regressions. The try-bots (see patcheset 9)
indicate some regressions, but it doesn't seem too bad.
Change-Id: Ia173ab20ee2a4904663db0f4ca2ffb196b203c77
Reviewed-on: https://chromium-review.googlesource.com/c/1319763
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57483}
As identified in the web-tooling-benchmark, there are specific code
patterns involving array indexed property accesses and subsequent
comparisons of those indices that lead to repeated Smi checks in the
optimized code, which in turn leads to high register pressure and
generally bad register allocation. An example of this pattern is
code like this:
```js
function f(a, n) {
const i = a[n];
if (n >= 1) return i;
}
```
The `a[n]` property access introduces a CheckBounds on `n`, which
later lowers to a `CheckedTaggedToInt32[dont-check-minus-zero]`,
however the `n >= 1` comparison has collected `SignedSmall` feedback
and so it introduces a `CheckedTaggedToTaggedSigned` operation. This
second Smi check is redundant and cannot easily be combined with the
earlier tagged->int32 conversion, since that also deals with heap
numbers and even truncates -0 to 0.
So we teach the RedundancyElimination to look at the inputs of these
speculative number comparisons and if there's a leading bounds check
on either of these inputs, we change the input to the result of the
bounds check. This avoids the redundant Smi checks later and generally
allows the SimplifiedLowering to do a significantly better job on the
number comparisons. We only do this in case of SignedSmall feedback
and only for inputs that are not already known to be in UnsignedSmall
range, to avoid doing too many (unnecessary) expensive lookups during
RedundancyElimination.
All of this is safe despite the fact that CheckBounds truncates -0
to 0, since the regular number comparisons in JavaScript identify
0 and -0 (unlike Object.is()). This also adds appropriate tests,
especially for the interesting cases where -0 is used only after
the code was optimized.
Bug: v8:6936, v8:7094
Change-Id: Ie37114fb6192e941ae1a4f0bfe00e9c0a8305c07
Reviewed-on: https://chromium-review.googlesource.com/c/1246181
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56428}
Remove the NumberConstant right hand side limitation for the speculative
number operation optimization, and extend the logic to also deal with
SpeculativeToNumber, which is common when dealing with postfix increment
and array operations.
Also add appropriate tests for all the relevant cases, specifically we
mjsunit tests to increase the general coverage for the various cases
here (in addition to dedicated unittests).
Bug: v8:8015
Change-Id: I8c92f98490c63b07eb19686efd404322979e57c4
Reviewed-on: https://chromium-review.googlesource.com/1235919
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56072}
This replaces the previous CheckStringAdd operator which deopts in case
the combined length overflows with a dedicated pure StringConcat operator.
This operator is similar to NewConsString in that it takes the resulting
length plus the two input strings. The operator relies on the length
being checked explicitly by the surrounding code instead of baking the
check into the operator itself. This way TurboFan can eliminate
redundant/unnecessary StringConcat operations, since they are pure now.
This also unifies the treatment of string addition in JSTypedLowering,
and generalizes the StringLength constant-folding to apply to more cases
not just the JSAdd cases inside JSTypedLowering.
Bug: v8:7902, v8:8015
Change-Id: I987ec39815a9464fd5fd9c4f7b26b709f94f2b3f
Reviewed-on: https://chromium-review.googlesource.com/1213205
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55725}
The new node is introduced for literal string addition and calling
String.prototype.concat in the typed lowering phase. It later might get optimized
away during redundancy elimination, keeping the performance of already existing
benchmarks with string addition. In case the operation is about to throw
(due to too long string being constructed) we just deoptimize, reusing
the interpreter logic for creating the error.
Modify relevant mjsunit and unit tests for string concatenation.
Bug: v8:7902
Change-Id: Ie97d39534df4480fa8d4fe3ba276d02ed5e750e3
Reviewed-on: https://chromium-review.googlesource.com/1193342
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55482}
The idea is to mark all the branches and loads participating in array
bounds checks, and let them contribute-to/use the poisoning register.
In the code, the marks for array indexing operations now contain
"Critical" in their name. By default (--untrusted-code-mitigations),
we only instrument the "critical" operations with poisoning.
With that in place, we also remove the array masking approach based
on arithmetic.
Since we do not propagate the poison through function calls,
we introduce a node for poisoning an index that is passed through
function call - the typical example is the bounds-checked index
that is passed to the CharCodeAt builtin.
Most of the code in this CL is threads through the three levels of
protection (safe, critical, unsafe) for loads, branches and flags.
Bug: chromium:798964
Change-Id: Ief68e2329528277b3ba9156115b2a6dcc540d52b
Reviewed-on: https://chromium-review.googlesource.com/995413
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52883}
This is part of the effort to decrease the amount of undefined behavior.
that v8 relies on.
The main change here is to represent types with class Type rather than
with pointer Type*. To make the CL smaller, I used an operator overload
hack to separate the change from `->` to `.`. I am working on a CL that
will remove the operator and change all those arrows to dots.
Bug: v8:3770
Change-Id: I71a197cb739a1467937bc95c2a757fab0469aa22
Reviewed-on: https://chromium-review.googlesource.com/1032551
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52872}
This CL also removes the JSBuiltinReducer, which is no longer needed.
Bug: v8:7340, v8:7250
Change-Id: I28896f6ce0d352047ea1cb7ea6de490818840faf
Reviewed-on: https://chromium-review.googlesource.com/1027853
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52799}
This CL changes the poisoning in the interpreter to use the
infrastructure used in the JIT.
This does not change the original flag semantics:
--branch-load-poisoning enables JIT mitigations as before.
--untrusted-code-mitigation enables the interpreter mitigations
(now realized using the compiler back-end), but does not enable
the back-end based mitigations for the Javascript JIT. So in effect
--untrusted-code-mitigation makes the CSA pipeline for bytecode handlers
use the same mechanics (including changed register allocation) that
--branch-load-poisoning enables for the JIT.
Bug: chromium:798964
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel
Change-Id: If7f6852ae44e32e6e0ad508e9237f24dec7e5b27
Reviewed-on: https://chromium-review.googlesource.com/928881
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52243}
This CL also cleans up some related naming in typed-optimization.
R=neis@chromium.org
Bug: v8:7531, v8:7570
Change-Id: If80e0e9642aaf6c58b164db2e1e0632cd5b0d051
Reviewed-on: https://chromium-review.googlesource.com/978066
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52182}
This also introduces two new simplified operators,
NumberIsFinite and ObjectIsFiniteNumber; the latter
handles all values, and the former is a fast-path
of the fast-path that is inserted by typed optimization
if we know the input has Type::Number.
Bug: v8:7340, v8:7250
Change-Id: I1b4812c01bf470bbff40fb3da6e11da543a22cd2
Reviewed-on: https://chromium-review.googlesource.com/951244
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51980}
UnalignedLoad is the only kind of load operation that defines its own
UnalignedLoadRepresentation type alias and LoadRepresentationOf function.
This is a problem because it means we cannot use the LOAD_MATCHER
infrastructure without defining all of this boilerplate for all the other
kinds of load operations. Since these aliases serve no real purpose,
it is best to unify UnalignedLoad to how its peers are handled.
Change-Id: I51a591eb82fb85edee66512136b23276e851f767
Reviewed-on: https://chromium-review.googlesource.com/951683
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51802}
This is a reland of b8bc26d099
Original change's description:
> [turbofan] Preserve order of compares in switches
>
> This CL makes sure that control flow optimization does
> not change the order of switches that ultimately get
> lowered to a series of comparisons anyway.
>
> Bug: v8:7326
> Change-Id: If004de6b71a7e9504d37754c847ca108a64e49db
> Reviewed-on: https://chromium-review.googlesource.com/941952
> Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#51679}
Bug: v8:7326
Change-Id: Ifbe61dece499c98bbd49fa3ae9b99ccf4e955ddc
Reviewed-on: https://chromium-review.googlesource.com/945770
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51691}
This CL also adds speculation to all Math builtins,
and refactors the JSCallReducer.
Bug: v8:7250, v8:7240
Change-Id: Icdaddb767e875bb191939d907f65c7a8dcf79b8b
Reviewed-on: https://chromium-review.googlesource.com/873916
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51426}
Moves generation of speculation poison to be based on the PC target vs the
actual PC being executed. The speculation poison is generated in the prologue
of the generated code if CompilationInfo::kGenerateSpeculationPoison is set.
The result is stored in a known register, which can then be read using the
SpeculationPoison machine node.
Currently we need to ensure the SpeculationPoison node is scheduled right after
the code prologue so that the poison register doesn't get clobbered. This is
currently not verified, however it's only use is in RawMachineAssembler where
it is manually scheduled early.
The Ignition bytecode handlers are updated to use this speculation poison
rather than one generated by comparing the target bytecode.
BUG=chromium:798964
Change-Id: I2a3d0cfc694e88d7a8fe893282bd5082f693d5e2
Reviewed-on: https://chromium-review.googlesource.com/893160
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51229}
Strings are immutable in JavaScript land (contrast with the runtime,
where we can truncate strings that haven't escaped to JavaScript yet),
so the length of a String is immutable. Thus loading the length of a
String is a pure operation and should be expressed as such (i.e. doesn't
depend on control or effect). The StringLength operator does exactly
this and is hooked up to the effect chain in the EffectControlLinearizer.
This will eventually allow us to simplify the optimization of string
concatention and other operations that are a bit cumbersome in TurboFan
currently, and it will also allow us to optimize string operations
across effectful operations, for example combining multiple invocations
to String#slice with the same inputs.
Bug: v8:5269, v8:6936, v8:7109, v8:7137
Change-Id: Iffcccbb0c7fc4cfe1281c10e7af24b40eba4c987
Reviewed-on: https://chromium-review.googlesource.com/799690
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49731}
Contributed by kanghua.yu@intel.com.
Bug: None
Change-Id: I5651ef38eb0c08deb97770a5eaa985dba2dab9a9
Reviewed-on: https://chromium-review.googlesource.com/604648
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Pan Deng <pan.deng@intel.com>
Cr-Commit-Position: refs/heads/master@{#47968}
These operators were only used by the old asm.js pipeline (with
fullcodegen and the AstGraphBuilder). When going through the new
pipeline, accesses to TypedArrays are handled by the native
context specialization during inlining.
Bug: v8:6409
Change-Id: Ib9b888c0b96f297a335580ee42dfa951bde566be
Reviewed-on: https://chromium-review.googlesource.com/612347
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47322}
Reland d8bfdb7a99
Original commit message:
If alignment parameter is set, the memory returned by the
StackSlot operator will be aligned according to the parameter.
The implementation goes like this. If alignment parameter is set
we allocate a bit more memory than actually needed and so we
can move the beginning of the StackSlot in order to have it aligned.
BUG=
Review-Url: https://codereview.chromium.org/2874713003
Cr-Commit-Position: refs/heads/master@{#45339}
We can compile a !== a and Number.isNaN(a) to ObjectIsNaN. The former is
commonly used to check for NaN, i.e. in case of equals in AngularJS.
R=jarin@chromium.org
BUG=v8:5267
Review-Url: https://codereview.chromium.org/2722483003
Cr-Commit-Position: refs/heads/master@{#43572}
Downside: this adds all kinds of weird includes in the .cc files.
(See design doc linked in the bug.)
BUG=v8:5402
Review-Url: https://codereview.chromium.org/2622503002
Cr-Commit-Position: refs/heads/master@{#42140}
Also lower JSToBoolean(x) where x is either some detectable receiver or
null, or any kind of receiver, null or undefined. Also fix a couple of
minor issues with the JSToBoolean lowering and tests.
R=yangguo@chromium.org
BUG=v8:5267
Review-Url: https://codereview.chromium.org/2530773002
Cr-Commit-Position: refs/heads/master@{#41241}
This adds a new ExternalPointer type, which is an Internal type that is
used for ExternalReferences and other pointer values, like the pointers
into the asm.js heap. It also adds a PointerConstant operator, which we
use to represents these raw constants (we can probably remove that
particular operator again once WebAssembly ships with the validator).
R=mvstanton@chromium.org
BUG=v8:5267,v8:5270
Review-Url: https://codereview.chromium.org/2494753003
Cr-Commit-Position: refs/heads/master@{#40923}
This is preparation for using TF to create builtins that handle variable number of
arguments and have to remove these arguments dynamically from the stack upon
return.
The gist of the changes:
- Added a second argument to the Return node which specifies the number of stack
slots to pop upon return in addition to those specified by the Linkage of the
compiled function.
- Removed Tail -> Non-Tail fallback in the instruction selector. Since TF now should
handles all tail-call cases except where the return value type differs, this fallback
was not really useful and in fact caused unexpected behavior with variable
sized argument popping, since it wasn't possible to materialize a Return node
with the right pop count from the TailCall without additional context.
- Modified existing Return generation to pass a constant zero as the additional
pop argument since the variable pop functionality
LOG=N
Review-Url: https://codereview.chromium.org/2446543002
Cr-Commit-Position: refs/heads/master@{#40699}
Reason for revert:
Seems to break arm64 sim debug and blocks roll:
https://build.chromium.org/p/client.v8.ports/builders/V8%20Linux%20-%20arm64%20-%20sim%20-%20debug/builds/3294
Original issue's description:
> [turbofan] Support variable size argument removal in TF-generated functions
>
> This is preparation for using TF to create builtins that handle variable number of
> arguments and have to remove these arguments dynamically from the stack upon
> return.
>
> The gist of the changes:
> - Added a second argument to the Return node which specifies the number of stack
> slots to pop upon return in addition to those specified by the Linkage of the
> compiled function.
> - Removed Tail -> Non-Tail fallback in the instruction selector. Since TF now should
> handles all tail-call cases except where the return value type differs, this fallback
> was not really useful and in fact caused unexpected behavior with variable
> sized argument popping, since it wasn't possible to materialize a Return node
> with the right pop count from the TailCall without additional context.
> - Modified existing Return generation to pass a constant zero as the additional
> pop argument since the variable pop functionality
>
> LOG=N
TBR=bmeurer@chromium.org,mstarzinger@chromium.org,epertoso@chromium.org,danno@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
NOPRESUBMIT=true
Review-Url: https://codereview.chromium.org/2473643002
Cr-Commit-Position: refs/heads/master@{#40691}
This is preparation for using TF to create builtins that handle variable number of
arguments and have to remove these arguments dynamically from the stack upon
return.
The gist of the changes:
- Added a second argument to the Return node which specifies the number of stack
slots to pop upon return in addition to those specified by the Linkage of the
compiled function.
- Removed Tail -> Non-Tail fallback in the instruction selector. Since TF now should
handles all tail-call cases except where the return value type differs, this fallback
was not really useful and in fact caused unexpected behavior with variable
sized argument popping, since it wasn't possible to materialize a Return node
with the right pop count from the TailCall without additional context.
- Modified existing Return generation to pass a constant zero as the additional
pop argument since the variable pop functionality
LOG=N
Review-Url: https://codereview.chromium.org/2446543002
Cr-Commit-Position: refs/heads/master@{#40678}
They are nops, but will be used when verifying the machine graph.
BUG=
Review-Url: https://codereview.chromium.org/2367413002
Cr-Commit-Position: refs/heads/master@{#39758}
For denominators that are powers of two, replace Float64 division with
multiplication by the reciprocal.
Additionally, replace division by -1 with negation, and multiplication by two
with addition.
BUG=
Review-Url: https://codereview.chromium.org/2347573002
Cr-Commit-Position: refs/heads/master@{#39478}
Previously we always lowered JSToBoolean(x:Number) to the subgraph
NumberLessThan(0.0, NumberAbs(x)), which deals with both 0, -0 and
NaNs appropriately. However this doesn't always generate the best,
especially when we can later derive from feedback that x is always
an Integral32 value, where the ideal code would be just a single
comparison to 0 w/o the absolute value computation.
R=mvstanton@chromium.org
BUG=v8:5267,v8:5270
Review-Url: https://codereview.chromium.org/2309953002
Cr-Commit-Position: refs/heads/master@{#39194}
If the type of a tracked field or element value is less precise than the
advertised type of the field or element load, then we replace the load
operation with a TypeGuard that guards the advertised type.
R=jarin@chromium.org
BUG=v8:5267
Review-Url: https://codereview.chromium.org/2295643002
Cr-Commit-Position: refs/heads/master@{#39032}
Up until now "-0.0 - x" was lowered in the instruction selector. I moved
the lowering now to the MachineOperatorReducer.
I did not remove the lowering from the instruction selector yet, I would
prefer to do that in a separate CL.
R=bmeurer@chromium.org
Review-Url: https://codereview.chromium.org/2226663002
Cr-Commit-Position: refs/heads/master@{#38417}
Introduce a dedicated NumberOperationHint enum that represents the
feedback we can use for speculative number operations.
BUG=v8:4930
Review-Url: https://codereview.chromium.org/2220573002
Cr-Commit-Position: refs/heads/master@{#38411}
Drive-by fix: actually match the hint in the IsSpeculativeBinopMatcher.
Review-Url: https://codereview.chromium.org/2191883002
Cr-Commit-Position: refs/heads/master@{#38176}
