We need to check the KeyedLoadIC state to guard against potential
deoptimization loops due to out-of-bounds accesses, because the IC
system uses the MEGAMORPHIC state to also signal that there was an
out-of-bounds access already.
R=jarin@chromium.org
Review-Url: https://codereview.chromium.org/2443893002
Cr-Commit-Position: refs/heads/master@{#40525}
Fixes:
- Remove OsrGuards on frame specialization (for asm.js).
- Handle the rename in the walk for native context.
- Fix LoadContext effect wiring for Osr context chains.
Review-Url: https://codereview.chromium.org/2388303006
Cr-Commit-Position: refs/heads/master@{#40021}
Reason for revert:
Tanks the world.
Original issue's description:
> [turbofan] Osr value typing + dynamic type checks on entry.
>
> This introduces a new OsrGuard node that is inserted during graph building
> to guard the inferred type of the OSR value.
>
> The type of the OSR value is inferred by running the typer before OSR
> deconstruction, and then taking the type from the phi that takes the
> OSR value. After the deconstruction, we throw the types away.
>
> At the moment we only support the SignedSmall OSR type and we always
> pick the tagged representation. Later, we might want to support more
> types (such as Number) and pick better representations (int32/float64).
>
> This CL also removes the OSR deconstruction tests because they build
> unrealistic graph (no effect chain, no loop termination). I considered
> adding the effect chains to the tests, but this would make the tests
> even more brittle.
>
> Committed: https://crrev.com/1f5dc90a900d222da44bee3eff171a2ba1e3c076
> Cr-Commit-Position: refs/heads/master@{#39971}
TBR=bmeurer@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
Review-Url: https://codereview.chromium.org/2395783002
Cr-Commit-Position: refs/heads/master@{#39985}
This introduces a new OsrGuard node that is inserted during graph building
to guard the inferred type of the OSR value.
The type of the OSR value is inferred by running the typer before OSR
deconstruction, and then taking the type from the phi that takes the
OSR value. After the deconstruction, we throw the types away.
At the moment we only support the SignedSmall OSR type and we always
pick the tagged representation. Later, we might want to support more
types (such as Number) and pick better representations (int32/float64).
This CL also removes the OSR deconstruction tests because they build
unrealistic graph (no effect chain, no loop termination). I considered
adding the effect chains to the tests, but this would make the tests
even more brittle.
Review-Url: https://codereview.chromium.org/2384113002
Cr-Commit-Position: refs/heads/master@{#39971}
This makes sure we only replace load operations for fields on virtual
objects. Even though data flow information for non-virtual (escaping)
allocations is available, it might be inaccurate in certain situations
where object state hasn't been cleared.
R=jarin@chromium.org
TEST=mjsunit/compiler/regress-escape-analysis-indirect
Review-Url: https://codereview.chromium.org/2369953002
Cr-Commit-Position: refs/heads/master@{#39776}
Reason for revert:
Tanks EarleyBoyer.
Original issue's description:
> [compiler] Properly guard the speculative optimizations for instanceof.
>
> Add a general feedback slot for instanceof similar to what we already have
> for for-in, which basically has a fast (indicated by the uninitialized
> sentinel) and a slow (indicated by the megamorphic sentinel) mode. Now
> we can only take the fast path when the feedback slot says it hasn't
> seen any funky inputs and nothing funky appeared in the prototype chain.
> In the TurboFan code we also deoptimize whenever we see a funky object
> (i.e. a proxy or an object that requires access checks) in the prototype
> chain (similar to what Crankshaft already did).
>
> Drive-by-fix: Also make Crankshaft respect the mode and therefore
> address the deopt loop in Crankshaft around instanceof.
>
> We might want to introduce an InstanceOfIC mechanism at some point and
> track the map of the right-hand side.
>
> BUG=v8:5267
> R=mvstanton@chromium.org
>
> Committed: https://crrev.com/a0484bc6116ebc2b855de87d862945e2ae07169b
> Cr-Commit-Position: refs/heads/master@{#39718}
TBR=mvstanton@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:5267
Review-Url: https://codereview.chromium.org/2365223003
Cr-Commit-Position: refs/heads/master@{#39736}
Add a general feedback slot for instanceof similar to what we already have
for for-in, which basically has a fast (indicated by the uninitialized
sentinel) and a slow (indicated by the megamorphic sentinel) mode. Now
we can only take the fast path when the feedback slot says it hasn't
seen any funky inputs and nothing funky appeared in the prototype chain.
In the TurboFan code we also deoptimize whenever we see a funky object
(i.e. a proxy or an object that requires access checks) in the prototype
chain (similar to what Crankshaft already did).
Drive-by-fix: Also make Crankshaft respect the mode and therefore
address the deopt loop in Crankshaft around instanceof.
We might want to introduce an InstanceOfIC mechanism at some point and
track the map of the right-hand side.
BUG=v8:5267
R=mvstanton@chromium.org
Review-Url: https://codereview.chromium.org/2370693002
Cr-Commit-Position: refs/heads/master@{#39718}
Extract String feedback on Add operation and utilize to lower ConsString
creation in JSTypedLowering when we know that a String addition will
definitely result in the creation of a ConsString.
Note that Crankshaft has to guard the potential length overflow of the
resulting string with an eager deoptimization exit, while we can safely
throw an exception in that case.
Also note that the bytecode pipeline does not currently provide the
String feedback for the addition, which has to be added.
BUG=v8:5267
R=jarin@chromium.org
Review-Url: https://codereview.chromium.org/2354853002
Cr-Commit-Position: refs/heads/master@{#39540}
This fixes the materialization of JSFunction objects to not rely on a
context being available. The context has been cleared because it might
be de-materiallized itself.
R=bmeurer@chromium.org
TEST=mjsunit/compiler/escape-analysis-materialize
BUG=chromium:644245
Review-Url: https://codereview.chromium.org/2320983002
Cr-Commit-Position: refs/heads/master@{#39277}
The trouble here is that the type of the induction variable might be
a bit ahead of the increment (JSAdd) operation's type. When we update
the type of the increment, we might only update the induction variable
type while the JSAdd type might be stale. If the induction variable typing
needs to fall back to normal phi typing (e.g., when the increment is not
an integer anymore), it might use the stale type.
To get around this, we fake monotonicity if we fallback to normal phi
typing. Another option would be to force re-typing of the increment
operation, but that seems to be harder to maintain.
BUG=chromium:644633
Review-Url: https://codereview.chromium.org/2320803002
Cr-Commit-Position: refs/heads/master@{#39261}
We were previously incorrectly changing:
sub r0, 0, r1
cmp r2, r0
b.cond <addr>
to:
cmn r2, r1
b.cond <addr>
for all conditions. This is incorrect for conditions involving the C (carry)
and V (overflow) flags, and in particular in the case where r1 = INT_MIN.
The optimization is still safe to perform for Equal and NotEqual since they
do not depend on the C and V flags.
BUG=
Review-Url: https://codereview.chromium.org/2318043002
Cr-Commit-Position: refs/heads/master@{#39246}
Migrate the isNaN, isFinite, Number.isFinite, Number.isInteger,
Number.isSafeInteger and Number.isNaN predicates to TurboFan
builtins and make them optimizable (for certain input types) in
JavaScript callees being optimized by TurboFan. That means both
the baseline and the optimized version is now always at maximum,
consistent performance. Especially TurboFan suffered from poor
baseline (and optimized) performance because it cannot play the
same weird tricks that Crankshaft plays for %_IsSmi.
This also adds a bunch of new tests to properly cover the use
of the Harmony predicates in optimized code.
R=franzih@chromium.org
BUG=v8:5049,v8:5267
Review-Url: https://codereview.chromium.org/2313073002
Cr-Commit-Position: refs/heads/master@{#39242}
Disable the propagation of truncations through Phi, Select or TypeGuard
if the output representation is tagged, because when the truncations are
taken we don't necessarily reflect this in the types and therefore we
might end up in a situation where we produce a word32 value, the type
says Number, and now we need to change that to tagged, which is not
possible since we don't know how to interpret the bits, i.e. whether the
value is Signed32 or Unsigned32.
BUG=chromium:644048
Review-Url: https://codereview.chromium.org/2311903002
Cr-Commit-Position: refs/heads/master@{#39186}
- Make constants more interesting.
- Add an addition to be done after the inlined call in the try-block.
- On command line, have a bit more output.
- New alternative that deopts from unoptimized code.
BUG=
R=jarin
Review-Url: https://codereview.chromium.org/2285743002
Cr-Commit-Position: refs/heads/master@{#38974}
These tests were spliced out of changelist 2216353002 and extended.
BUG=
Review-Url: https://codereview.chromium.org/2245263003
Cr-Commit-Position: refs/heads/master@{#38906}
Reason for revert:
Octane/Mandreel aborts with an exception now:
TypeError: __FUNCTION_TABLE__[(r2 >> 2)] is not a function
Original issue's description:
> [turbofan] Insert dummy values when changing from None type.
>
> Currently we choose the MachineRepresentation::kNone representation for
> values of Type::None, and when converting values from the kNone representation
> we use "impossible" conversions that will crash at runtime. This
> assumes that the impossible conversions should never be hit (the only
> way to produce the impossible values is to perform an always-failing
> runtime check on a value, such as Smi-checking a string). Note that
> this assumes that the runtime check is executed before the impossible
> convesrion.
>
> Introducing BitwiseOr type feedback broke this in two ways:
>
> - we always pick Word32 representation for bitwise-or, so the
> impossible conversion does not trigger (it only triggers with
> None representation), and we could end up with unsupported
> conversions from Word32.
>
> - even if we inserted impossible conversions, they are pure conversions.
> Since untagging, bitwise-or operations are also pure, we could hoist
> all these before the smi check of the inputs and we could hit the
> impossible conversions before we get to the smi check.
>
> This CL addresses this by just providing dummy values for conversions
> from the Type::None type. It also removes the impossible-to-* conversions.
>
> BUG=chromium:638132
>
> Committed: https://crrev.com/c83b21ab755f1420b6da85b3ff43d7e96ead9bbe
> Cr-Commit-Position: refs/heads/master@{#38883}
TBR=mstarzinger@chromium.org,jarin@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:638132
Review-Url: https://codereview.chromium.org/2280613002
Cr-Commit-Position: refs/heads/master@{#38893}
Currently we choose the MachineRepresentation::kNone representation for
values of Type::None, and when converting values from the kNone representation
we use "impossible" conversions that will crash at runtime. This
assumes that the impossible conversions should never be hit (the only
way to produce the impossible values is to perform an always-failing
runtime check on a value, such as Smi-checking a string). Note that
this assumes that the runtime check is executed before the impossible
convesrion.
Introducing BitwiseOr type feedback broke this in two ways:
- we always pick Word32 representation for bitwise-or, so the
impossible conversion does not trigger (it only triggers with
None representation), and we could end up with unsupported
conversions from Word32.
- even if we inserted impossible conversions, they are pure conversions.
Since untagging, bitwise-or operations are also pure, we could hoist
all these before the smi check of the inputs and we could hit the
impossible conversions before we get to the smi check.
This CL addresses this by just providing dummy values for conversions
from the Type::None type. It also removes the impossible-to-* conversions.
BUG=chromium:638132
Review-Url: https://codereview.chromium.org/2266823002
Cr-Commit-Position: refs/heads/master@{#38883}
Unfortunately, I was unable to produce a repro without asm.js. In normal
JavaScript, the bounds check renaming saves us.
I have not done anything about the index variable aliasing and handling
of differently sized elements yet!
BUG=chromium:639210, v8:5266
Review-Url: https://codereview.chromium.org/2270793004
Cr-Commit-Position: refs/heads/master@{#38874}
Unify the representation selection rules for NumberAdd/Subtract and
SpeculativeNumberAdd/Subtract wrt. Int32Add/Sub selection. We can
safely use Int32Add/Sub as long as the inputs are in the safe additive
integer range and the output is either truncated to Word32 or provably
in Signed32 or Unsigned32 range.
R=jarin@chromium.org
Review-Url: https://codereview.chromium.org/2253293005
Cr-Commit-Position: refs/heads/master@{#38746}
At the moment, two NumberConstant nodes get different type even if their
value is the same because we always allocate a new heap number for
each number constant. This can lead to replacing a node with a node of
disjoint type in value numbering, which can result in incorrect code
down the line because of inconsistent types.
This fix makes sure that we only replace a node with a sub-type
node. Once we introduce a proper type for number constants, we can
move back to the intersection typing in value numbering.
Unfortunately, it is quite hard to write a repro for this because we cache NumberConstant nodes. We only throw away cached values that have too many conflicts (>5), so the test has to contain values that fall into the same bucket. That's where the magic floating point numbers in the test come from (they have the same low 8-bits of their hashes).
BUG=chromium:633497
Review-Url: https://codereview.chromium.org/2251833002
Cr-Commit-Position: refs/heads/master@{#38675}
This adds a very first version of inlined Array.prototype.pop into
TurboFan optimized code. We currently limit the inlining to fast
object or smi elements, until the unclear situation around hole NaNs
is resolved and we have a clear semantics inside the compiler.
It's also probably overly defensive in when it's safe to inline
the call to Array.prototype.pop, but we can always extend that
later once we have sufficient trust in the implementation and see
an actual need to extend it.
BUG=v8:2229,v8:3952,v8:5267
R=epertoso@chromium.org
Review-Url: https://codereview.chromium.org/2239703002
Cr-Commit-Position: refs/heads/master@{#38578}
This switches the interface of the runtime profiler to use frames as
opposed to functions for performing on-stack replacement. Requests for
such replacements need to target a specific frame. This will enable us
to activate bytecode as well as baseline code for the same function.
The existing %OptimizeOsr runtime function also had to adapted and now
takes an optional stack depth to target a specific stack frame.
R=bmeurer@chromium.org
BUG=v8:4764
Review-Url: https://codereview.chromium.org/2230783004
Cr-Commit-Position: refs/heads/master@{#38548}
We now deopt when the lhs of a mod is negative and the rhs is 1 too (previously, we erroneusly returned 0 instead of -0).
BUG=v8:5278
R=bmeurer@chromium.org
Review-Url: https://codereview.chromium.org/2233713002
Cr-Commit-Position: refs/heads/master@{#38525}
If we infer loop variable bounds, we need to insert a type rename node
(sigma) to make sure that simplified lowering can choose representations
consistently.
Review-Url: https://codereview.chromium.org/2222513002
Cr-Commit-Position: refs/heads/master@{#38391}
This introduces a bunch of new tests that test various aspects of
accessor inlining in TurboFan (without the actual inlining), and does
the appropriate fixes to the AstGraphBuilder. The actual inlining CL
will land separately (so we don't need to revert the tests and fixes
if the accessor CL has to be reverted).
R=jarin@chromium.org
Review-Url: https://codereview.chromium.org/2197913002
Cr-Commit-Position: refs/heads/master@{#38191}
Drive-by fix: actually match the hint in the IsSpeculativeBinopMatcher.
Review-Url: https://codereview.chromium.org/2191883002
Cr-Commit-Position: refs/heads/master@{#38176}
This required the introduction of the CheckedNumberOrOddballAsWord32 use info, and a change in the RepresentationChanger to handle it.
BUG=
Review-Url: https://codereview.chromium.org/2184513003
Cr-Commit-Position: refs/heads/master@{#38086}
After multiplying two integers we emit code like:
if (result == 0) {
if (OR_OPERATION(rhs, lhs) < 0) {
DEOPT;
}
}
This CL allows us to eliminate the OR and comparison if either rhs or
lhs is a negative number, reducing the code to:
if (result == 0) DEOPT;
BUG=
Review-Url: https://codereview.chromium.org/2167643002
Cr-Commit-Position: refs/heads/master@{#38016}
Use the ForInFilterStub directly. Hence we will only jump to the runtime for
special receivers (instance_type <= LAST_SPECIAL_RECEIVER_TYPE) and for
converting element indices which are not in the string cache.
BUG=
Review-Url: https://codereview.chromium.org/2151773002
Cr-Commit-Position: refs/heads/master@{#37934}
This makes sure that we preserve call's tailness even if we have
introduced a loop exit between the call and the return.
BUG=chromium:628773
Review-Url: https://codereview.chromium.org/2155123002
Cr-Commit-Position: refs/heads/master@{#37832}
In int32 multiplication, if we have a positive integer as input, then we know we can't produce a -0 answer. The same is true if truncation is applied (x * y | 0). Without this information, we have to rather annoyingly check if the result of multiplication is 0, then OR the inputs to check for negativity, and possibly return -0. In TurboFan, we'll deopt in this case.
BUG=
Review-Url: https://codereview.chromium.org/2154073002
Cr-Commit-Position: refs/heads/master@{#37831}
Delaying for merges caused branch cloning using dummy effect phi inputs,
potentially splitting the effect chain at start.
We still have to delay the creation for loops because we need to break
cycles.
BUG=chromium:628403
Review-Url: https://codereview.chromium.org/2159603002
Cr-Commit-Position: refs/heads/master@{#37808}
This makes sure that the uses of PlainPrimitiveToNumber get a more
precise type (so that the uses know how to interpret the output
representation).
BUG=chromium:628516
Review-Url: https://codereview.chromium.org/2151223002
Cr-Commit-Position: refs/heads/master@{#37792}
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}
This drops the %_ValueOf intrinsic, but keeps the runtime entry
%ValueOf for now, by either migrating the functionality (mostly
Debug mirror or toString/valueOf methods) to C++ or TurboFan
builtins, or switching to the %ValueOf runtime call when it's
not performance critical anyways.
The %_ValueOf intrinsic was one of the last blockers for fixing
the unsound machine operator typing in TurboFan.
R=yangguo@chromium.org
BUG=v8:5049
Committed: https://crrev.com/293bd7882987f00e465710ce468bfb1eaa7d3fa2
Review-Url: https://codereview.chromium.org/2126453002
Cr-Original-Commit-Position: refs/heads/master@{#37512}
Cr-Commit-Position: refs/heads/master@{#37519}
Reason for revert:
[Sheriff] Breaks without i18n:
https://build.chromium.org/p/client.v8/builders/V8%20Linux%20-%20noi18n%20-%20debug/builds/8466
Original issue's description:
> [intrinsic] Drop the %_ValueOf intrinsic.
>
> This drops the %_ValueOf intrinsic, but keeps the runtime entry
> %ValueOf for now, by either migrating the functionality (mostly
> Debug mirror or toString/valueOf methods) to C++ or TurboFan
> builtins, or switching to the %ValueOf runtime call when it's
> not performance critical anyways.
>
> The %_ValueOf intrinsic was one of the last blockers for fixing
> the unsound machine operator typing in TurboFan.
>
> R=yangguo@chromium.org
> BUG=v8:5049
>
> Committed: https://crrev.com/293bd7882987f00e465710ce468bfb1eaa7d3fa2
> Cr-Commit-Position: refs/heads/master@{#37512}
TBR=yangguo@chromium.org,bmeurer@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:5049
Review-Url: https://codereview.chromium.org/2117273002
Cr-Commit-Position: refs/heads/master@{#37514}