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}
Implement UnalignedLoad and UnalignedStore optional
turbofan operators and use them in WasmCompiler for unaligned
memory access.
BUG=
Review-Url: https://codereview.chromium.org/2122853002
Cr-Commit-Position: refs/heads/master@{#37988}
So far we don't have a useful way to inline Math.max or Math.min in
TurboFan optimized code. This adds new operators NumberMax and NumberMin
and changes the Float64Max/Float64Min operators to have JavaScript
semantics instead of the C++ semantics that it had previously.
This also removes support for recognizing the tenary case in the
CommonOperatorReducer, since that doesn't seem to have any positive
impact (and actually doesn't show up in regular JavaScript, where
people use Math.max/Math.min instead).
Drive-by-fix: Also nuke the unused Float32Max/Float32Min operators.
R=jarin@chromium.org
Review-Url: https://codereview.chromium.org/2170343002
Cr-Commit-Position: refs/heads/master@{#37971}
Typed lowering now produces SpeculativeNumberShiftLeft for JSShiftLeft if the type feedback is kSignedSmall or kSigned32.
BUG=v8:4583
LOG=n
Review-Url: https://codereview.chromium.org/2150553002
Cr-Commit-Position: refs/heads/master@{#37762}
Import fdlibm versions of acos, acosh, asin and asinh, which are more
precise and produce the same result across platforms (we were using
libm versions for asin and acos so far, where both speed and precision
depended on the operating system so far). Introduce appropriate TurboFan
operators for these functions and use them both for inlining and for the
generic builtin.
Also migrate the Math.imul and Math.fround builtins to TurboFan builtins
to ensure that their behavior is always exactly the same as the inlined
TurboFan version (i.e. C++ truncation semantics for double to float
don't necessarily meet the JavaScript semantics).
For completeness, also migrate Math.sign, which can even get some nice
love in TurboFan.
Drive-by-fix: Some alpha-sorting on the Math related functions, and
cleanup the list of Math intrinsics that we have to export via the
native context currently.
BUG=v8:3266,v8:3496,v8:3509,v8:3952,v8:5169,v8:5170,v8:5171,v8:5172
TBR=rossberg@chromium.orgR=franzih@chromium.org
Review-Url: https://codereview.chromium.org/2116753002
Cr-Commit-Position: refs/heads/master@{#37476}
The only real use case left for TypeGuard was the renaming inside the
LoadElimination, but this case only occurs in dead code (guarded by a
previous Check), so it's not relevant, and we can drop the TypeGuard
operator completely.
R=jarin@chromium.org
Review-Url: https://codereview.chromium.org/2108793003
Cr-Commit-Position: refs/heads/master@{#37361}
Introduce a new machine operator Float64Pow that for now is backed by
the existing MathPowStub to start the unification of Math.pow, and at
the same time address the main performance issue that TurboFan still has
with the imaging-darkroom benchmark in Kraken.
Also migrate the Math.pow builtin itself to a TurboFan builtin and
remove a few hundred lines of hand-written platform code for special
handling of the fullcodegen Math.pow version.
BUG=v8:3599,v8:5086,v8:5157
Review-Url: https://codereview.chromium.org/2103733003
Cr-Commit-Position: refs/heads/master@{#37323}
Add NumberAbs operator to implement an inline version of Math.abs, that
can be optimized and eliminated. We don't use any speculation here, but
for now stick to the information we can infer (this way we avoid the
inherent deopt loops that Crankshaft has around Math.abs).
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
R=jarin@chromium.org
BUG=v8:5086
Review-Url: https://codereview.chromium.org/2096403002
Cr-Commit-Position: refs/heads/master@{#37306}
Import base::ieee754::tan() from fdlibm and introduce Float64Tan TurboFan
operator based on that, similar to what we do for Float64Cos and Float64Sin.
Rewrite Math.tan() as TurboFan builtin and use those operators to also
inline Math.tan() into optimized TurboFan functions.
Drive-by-fix: Kill the %_ConstructDouble intrinsics, and provide only
the %ConstructDouble runtime entry for writing tests.
BUG=v8:5086,v8:5126
R=yangguo@chromium.org
Review-Url: https://codereview.chromium.org/2083453002
Cr-Commit-Position: refs/heads/master@{#37087}
Import base::ieee754::cos() and base::ieee754::sin() from fdlibm and
introduce Float64Cos and Float64Sin TurboFan operator based on that,
similar to what we do for Float64Log. Rewrite Math.cos() and Math.sin()
as TurboFan builtins and use those operators to also inline Math.cos()
and Math.sin() into optimized TurboFan functions.
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_chromium_rel_ng;tryserver.blink:linux_blink_rel
R=mvstanton@chromium.org
BUG=v8:5086,v8:5118
Review-Url: https://codereview.chromium.org/2073123002
Cr-Commit-Position: refs/heads/master@{#37072}
