TurboFan truncated null to +0 even in contexts such as -0 == null
because it was not handling the TypeCheck correctly. This restricts
the type conversion case to not apply truncation in this case (see
comment in patch).
Change-Id: Ia38ace9608800c8d61988de402a31dd863d9160a
Bug: chromium:961237
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1609538
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61446}
GraphBuilderTester was introduced at a time where RawMachineAssembler
was going to be deprecated (https://codereview.chromium.org/1423923003/).
Now we know that it's not going to happen any time soon.
Since GraphBuilderTester it's only used in one test which can use
RawMachineAssembler, I updated it and removed the class.
Now the .h file had another class, which is now the only class in the file.
Therefore, I renamed it and updated the include calls to it.
Also updated the include commands: some were not necessary, and some others
could be moved to more aptly places.
Bug: v8:9183
Change-Id: I44bf16090c0515b1b9ff6cbded1bdb0adb4e44e2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1594563
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Ben Titzer <titzer@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61269}
Includes both changing from compressed pointers and to compressed pointers.
Also added tests to the representation changer test
B
Cq-Include-Trybots: luci.v8.try:v8_linux64_pointer_compression_rel_ng,v8_linux64_arm64_pointer_compression_rel_ng
Bug: v8:8977
Change-Id: I8a13f6b7ec2208442aa354949173cc9061bce168
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1533866
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60587}
This CL changes the usage pattern from
FOR_XXX_VALUES(i) { Use(*i); }
to
FOR_XXX_VALUES(i) { Use(i); }
which is way more intuitive.
Note that the replacement in the uses was done via regular expression,
so it's purely mechanical. In two locations I removed unneeded braces
around the macro, because they confused clang-format.
I plan to do more cleanups (remove redundant assignments within the
FOR_XXX_VALUES body) in a follow-up CL.
R=mstarzinger@chromium.org
Bug: v8:8562
Change-Id: I4329bfcf34e5b077d19b50f4204ceb3b4340fe61
Reviewed-on: https://chromium-review.googlesource.com/c/1449615
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59287}
Apart from being more in-line with the style guide, this allows to use
DEFINE_LAZY_LEAKY_OBJECT_GETTER for defining {TypeCache::Get}.
R=tebbi@chromium.org
Bug: v8:8562
Change-Id: I016b28624950ce9404180fc1ca1a232551f75cd0
Reviewed-on: https://chromium-review.googlesource.com/c/1392201
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58500}
Merging the temporary HeapObjectPtr back into HeapObject.
Bug: v8:3770
Change-Id: I5bcd23ca2f5ba862cf5b52955dca143e531c637b
Reviewed-on: https://chromium-review.googlesource.com/c/1386492
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58410}
This change ensures that we do not try to check the conversion of a floating
point constant, but insert the floating point constant instead.
Change-Id: I1c65e3a69acaea2ff805ba10317f64c0ac0ba098
Reviewed-on: https://chromium-review.googlesource.com/c/1340257
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57630}
This introduces Word64 support for the CheckBounds operator, which now
lowers to either CheckedUint32Bounds or CheckedUint64Bounds after the
representation selection. The right hand side of CheckBounds can now
be any positive safe integer on 64-bit architectures, whereas it remains
Unsigned31 for 32-bit architectures. We only use the extended Word64
support when the right hand side is outside the Unsigned31 range, so
for everything except DataViews this means that the performance should
remain the same. The typing rule for the CheckBounds operator was
updated to reflect this new behavior.
The CheckBounds with a right hand side outside the Unsigned31 range will
pass a new Signed64 feedback kind, which is handled with newly introduced
CheckedFloat64ToInt64 and CheckedTaggedToInt64 operators in representation
selection.
The JSCallReducer lowering for DataView getType()/setType() methods was
updated to not smi-check the [[ByteLength]] and [[ByteOffset]] anymore,
but instead just use the raw uintptr_t values and operate on any value
(for 64-bit architectures these fields can hold any positive safe
integer, for 32-bit architectures it's limited to Unsigned31 range as
before). This means that V8 can now handle huge DataViews fully, without
falling off a performance cliff.
This refactoring even gave us some performance improvements, on a simple
micro-benchmark just exercising different DataView accesses we go from
testDataViewGetUint8: 796 ms.
testDataViewGetUint16: 997 ms.
testDataViewGetInt32: 994 ms.
testDataViewGetFloat64: 997 ms.
to
testDataViewGetUint8: 895 ms.
testDataViewGetUint16: 889 ms.
testDataViewGetInt32: 888 ms.
testDataViewGetFloat64: 890 ms.
meaning we lost around 10% on the single byte case, but gained 10% across
the board for all the other element sizes.
Design-Document: http://bit.ly/turbofan-word64
Bug: chromium:225811, v8:4153, v8:7881, v8:8171, v8:8383
Change-Id: Ic9d1bf152e47802c04dcfd679372e5c85e4abc83
Reviewed-on: https://chromium-review.googlesource.com/c/1303732
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57095}
When converting a Signed32\/MinusZero value from Word32 to Float64
representation or just passing it through as Word32 (with potential
type checks on it) we don't need to worry about -0 as long as the uses
identify 0 and -0.
Drive-by-fix: Fix the CheckChange() helper in the representation
changer test to pass Truncation::Any() by default.
Bug: chromium:891639, chromium:891612, chromium:891627, v8:8015, v8:8178
Change-Id: I06948ec0cdb8e778cb3678124ef927277a5f40ee
Reviewed-on: https://chromium-review.googlesource.com/c/1258902
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56369}
Teach TurboFan about representation changes from Float64 to Word64 where
the input value is already known to be within the Int64 or Uint64 range.
While not all of these values have representations in Float64, those
that do can be converted to Word64 without loss of precision.
Same is true for Tagged to Word64 conversions, although here we don't
(currently) need the case for Uint64 ranges, so we can skip adding an
operator for that until it becomes necessary (there's a hard check in
the code so it'll not silently cause trouble).
Bug: v8:8178
Change-Id: Ie99b0bc9af096bd927f63b26b0a61e66454bc4ae
Reviewed-on: https://chromium-review.googlesource.com/1231593
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56022}
Word8 and Word16 representation is treated like Word32 for the sake of
TurboFan's representation selection, but this was missing from the
Word64 conversions.
Bug: chromium:884933, v8:4153, v8:7881, v8:8171, v8:8178
Change-Id: If7b69cdd02b12546d87bba0643e9ee9cb35cb299
Reviewed-on: https://chromium-review.googlesource.com/1229953
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55983}
This change introduces the necessary conversion operators to convert
from Word64 to other representations (Tagged, Word32, Float64, etc.),
and plugs in the Word64 representation for NumberAdd/NumberSubtract,
such that TurboFan will go to Int64Add/Sub on 64-bit architectures
when the inputs and the output of the operation is in safe integer
range. This includes the necessary changes to the Deoptimizer to be
able to rematerialize Int64 values as Smi/HeapNumber when going back
to Ignition later.
This change might affect performance, although measurements indicate
that there should be no noticable performance impact.
The goal is to have TurboFan support Word64 representation to a degree
that changing the TypedArray length to an uint64_t (for 64-bit archs)
becomes viable and doesn't have any negative performance implications.
Independent of that we might get performance improvements in other areas
such as for crypto code later.
Bug: v8:4153, v8:7881, v8:8171, v8:8178
Design-Document: bit.ly/turbofan-word64
Change-Id: I29d56e2a31c1bae61d04a89d29ea73f21fd49c59
Cq-Include-Trybots: luci.chromium.try:linux_chromium_headless_rel
Reviewed-on: https://chromium-review.googlesource.com/1225709
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55937}
This adds support to TurboFan's representation selection for the Word64
representation, and makes use of that to handle indices for memory access
and allocation instructions (i.e. LoadElement, StoreElement, Allocate,
etc.). These instructions had previously used Word32 as representation
for the indices / sizes, and then internally converted it to the correct
representation (aka Word64 on 64-bit architectures) later on, but that
was kind of brittle, and sometimes led to weird generated code.
The change thus only adds support to convert integer values in the safe
integer range from all kinds of representations to Word64 (on 64-bit
architectures). We don't yet handle the opposite direction and none of
the representation selection heuristics for the numeric operations were
changed so far. This will be done in follow-up CLs.
This CL itself is supposed to be neutral wrt. functionality, and only
serves as a starting point, and a cleanup for the (weird) implicit
Word64 index/size handling.
Bug: v8:7881, v8:8015, v8:8171
Design-Document: http://bit.ly/turbofan-word64
Change-Id: I3c6961a0e96cbc3fb8ac9d3e1be8f2e5c89bfd25
Cq-Include-Trybots: luci.chromium.try:linux_chromium_headless_rel
Reviewed-on: https://chromium-review.googlesource.com/1224932
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55886}
This removes Type::operator-> which was used to split the change that
removed undefined misuse of Type* to represent integers.
Bug: v8:3770
Change-Id: I9a5bce5ccdc75461a7b939b4070cb58fe6040d99
Reviewed-on: https://chromium-review.googlesource.com/1033736
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52878}
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}
Simplified lowering may loose feedback by inserting Checked
conversions for BoundsChecks in case the bounds check gets
optimized away later on.
Bug: v8:7127
Change-Id: I254a29ba4e578d653d1dee2d70582ce0a4b57789
Reviewed-on: https://chromium-review.googlesource.com/878743
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50783}
This change is quite invasive, because CheckSmi is lowered
through representation change depending on UseInfo to several
different checked conversion operators. This CL adds feedback
to every checked conversion operator to Int32.
Bug: v8:7127, v8:7204
Change-Id: Icb780e5a69d321c2ec161c3c2a32984bdcf101f1
Reviewed-on: https://chromium-review.googlesource.com/831521
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@{#50167}
This introduces a new truncation bit for truncation of minus-zero to zero.
At the moment it is only used to handle the limit cases of deopt, such as the
one in the Google maps workload (see simplified version below), where the -q
(which is desugared to q * -1.0) currently deoptimizes because the result would
produce minus zero. To handle this situation, we exploit the knowledge that
righthand side of + cannot be -0, so even if lefthand side was -0, the result
would still be 0 (so the + operation cannot distinguish between left hand side
0 and -0).
function f(q) {
q -= 4;
return (-q) + q;
}
f(10);
f(10);
%OptimizeFunctionOnNextCall(f);
f(4);
Review-Url: https://codereview.chromium.org/2734253002
Cr-Commit-Position: refs/heads/master@{#43661}
Don't unconditionally assume that Tagged->Word32 changes are always
truncating independent of the type of the input. Work-around the
remaining issues with for-in by properly renaming the index if it's
not already of appropriate type (happens with generators or OSR).
R=jarin@chromium.org
Review-Url: https://codereview.chromium.org/2545393002
Cr-Commit-Position: refs/heads/master@{#41484}
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}
The only way to get a minus zero result from subtraction is
(-0) - (+0) = -0, hence checking for minus zero on the RHS is
redundant. This is causing some unnecessary deoptimisations
in Box2D from Octane on 32-bit platforms.
BUG=
Review-Url: https://codereview.chromium.org/2410883003
Cr-Commit-Position: refs/heads/master@{#40207}
Add a dedicated simplified operator to inline the general case for the
ToBoolean conversion. In a follow up CL we will also use the ToBoolean
hints gathered by the baseline compiler.
CQ_INCLUDE_TRYBOTS=master.tryserver.v8:v8_linux_arm64_gc_stress_dbg
R=jarin@chromium.org
BUG=v8:5267
Committed: https://crrev.com/8c50b51ab3d21efcd2f6900d83962159f21e1590
Review-Url: https://codereview.chromium.org/2167593002
Cr-Original-Commit-Position: refs/heads/master@{#37882}
Cr-Commit-Position: refs/heads/master@{#39420}
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}
This leads to a better handling of the Smi case when we introduce a checked truncation from a number or oddbal to a 32 bit word, which we were previously doing by concatenating a Smi to float64 conversion with a float64 to word32 truncation.
BUG=
Review-Url: https://codereview.chromium.org/2191503002
Cr-Commit-Position: refs/heads/master@{#38091}
Add a dedicated simplified operator to inline the general case for the
ToBoolean conversion. In a follow up CL we will also use the ToBoolean
hints gathered by the baseline compiler.
Review-Url: https://codereview.chromium.org/2167593002
Cr-Commit-Position: refs/heads/master@{#37882}
This introduces optimized number operations based on type feedback.
Summary of changes:
1. Typed lowering produces SpeculativeNumberAdd/Subtract for JSAdd/Subtract if
there is suitable feedback. The speculative nodes are connected to both the
effect chain and the control chain and they retain the eager frame state.
2. Simplified lowering now executes in three phases:
a. Propagation phase computes truncations by traversing the graph from uses to
definitions until checkpoint is reached. It also records type-check decisions
for later typing phase, and computes representation.
b. The typing phase computes more precise types base on the speculative types (and recomputes
representation for affected nodes).
c. The lowering phase performs lowering and inserts representation changes and/or checks.
3. Effect-control linearization lowers the checks to machine graphs.
Notes:
- SimplifiedLowering will be refactored to have handling of each operation one place and
with clearer input/output protocol for each sub-phase. I would prefer to do this once
we have more operations implemented, and the pattern is clearer.
- The check operations (Checked<A>To<B>) should have some flags that would affect
the kind of truncations that they can handle. E.g., if we know that a node produces
a number, we can omit the oddball check in the CheckedTaggedToFloat64 lowering.
- In future, we want the typer to reuse the logic from OperationTyper.
BUG=v8:4583
LOG=n
Review-Url: https://codereview.chromium.org/1921563002
Cr-Commit-Position: refs/heads/master@{#36674}
This prevents the compiler from optimizing
f64-to-tagged(tagged-to-f64(x)) ==> x
for non-number x (such as undefined).
Review-Url: https://codereview.chromium.org/2027593002
Cr-Commit-Position: refs/heads/master@{#36613}
Now ChangeLowering is only concerned with lowering memory access and
allocation operations, and all changes are consistently lowered during
the effect/control linearization pass. The next step is to move the
left over lowerings to a pass dedicated to eliminate redundant loads and
stores, eliminate write barriers, fold and inline allocations.
Drive-by-fix: Rename ChangeBitToBool to ChangeBitToTagged,
ChangeBoolToBit to ChangeTaggedToBit, and ChangeInt31ToTagged to
ChangeInt31ToTaggedSigned for consistency.
CQ_INCLUDE_TRYBOTS=tryserver.v8:v8_linux64_tsan_rel
Committed: https://crrev.com/ceca5ae308bddda166651c654f96d71d74f617d0
Cr-Commit-Position: refs/heads/master@{#35924}
Review-Url: https://codereview.chromium.org/1941673002
Cr-Commit-Position: refs/heads/master@{#35929}
Reason for revert:
[Sheriff] Breaks mac gc stress:
https://build.chromium.org/p/client.v8/builders/V8%20Mac%20GC%20Stress/builds/5821
Original issue's description:
> [turbofan] Remove left-over change bits from ChangeLowering.
>
> Now ChangeLowering is only concerned with lowering memory access and
> allocation operations, and all changes are consistently lowered during
> the effect/control linearization pass. The next step is to move the
> left over lowerings to a pass dedicated to eliminate redundant loads and
> stores, eliminate write barriers, fold and inline allocations.
>
> Also remove the atomic regions now that we wire everything into the
> effect chain properly. This is an important step towards allocation
> inlining.
>
> Drive-by-fix: Rename ChangeBitToBool to ChangeBitToTagged,
> ChangeBoolToBit to ChangeTaggedToBit, and ChangeInt31ToTagged to
> ChangeInt31ToTaggedSigned for consistency.
>
> CQ_INCLUDE_TRYBOTS=tryserver.v8:v8_linux64_tsan_rel
>
> Committed: https://crrev.com/ceca5ae308bddda166651c654f96d71d74f617d0
> Cr-Commit-Position: refs/heads/master@{#35924}
TBR=ishell@chromium.org,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/1942733002
Cr-Commit-Position: refs/heads/master@{#35927}
Now ChangeLowering is only concerned with lowering memory access and
allocation operations, and all changes are consistently lowered during
the effect/control linearization pass. The next step is to move the
left over lowerings to a pass dedicated to eliminate redundant loads and
stores, eliminate write barriers, fold and inline allocations.
Also remove the atomic regions now that we wire everything into the
effect chain properly. This is an important step towards allocation
inlining.
Drive-by-fix: Rename ChangeBitToBool to ChangeBitToTagged,
ChangeBoolToBit to ChangeTaggedToBit, and ChangeInt31ToTagged to
ChangeInt31ToTaggedSigned for consistency.
CQ_INCLUDE_TRYBOTS=tryserver.v8:v8_linux64_tsan_rel
Review-Url: https://codereview.chromium.org/1941673002
Cr-Commit-Position: refs/heads/master@{#35924}
This allows us to get rid of the "push TruncateFloat64ToInt32 into Phi"
trick that was used in the MachineOperatorReducer to combine the
ChangeTaggedToFloat64 and TruncateFloat64ToInt32 operations. Instead of
doing that later, we can just introduce the proper operator during the
representation selection directly.
Also separate the TruncateFloat64ToInt32 machine operator, which had two
different meanings depending on a flag (either JavaScript truncation or
C++ style round to zero). Now there's a TruncateFloat64ToWord32 which
represents the JavaScript truncation (implemented via TruncateDoubleToI
macro + code stub) and the RoundFloat64ToInt32, which implements the C++
round towards zero operation (in the same style as the other WebAssembly
driven Round* machine operators).
R=jarin@chromium.org
Review URL: https://codereview.chromium.org/1919513002
Cr-Commit-Position: refs/heads/master@{#35743}
Get rid of further typing checks from ChangeLowering and put them into
the representation selection pass instead (encoding the information in
the operator instead).
Drive-by-change: Rename ChangeSmiToInt32 to ChangeTaggedSignedToInt32
for consistency about naming Tagged, TaggedSigned and TaggedPointer.
R=jarin@chromium.org
Review URL: https://codereview.chromium.org/1909343002
Cr-Commit-Position: refs/heads/master@{#35723}
If we have to convert a float64 value to tagged representation and we
already know that the value is either in Signed31/Signed32 or
Unsigned32 range, then we can just convert the float64 to word32 and
use the fast word32 to tagged conversion. Doing this in
ChangeLowering (or the effect linearization pass) would be unsound, as
the types on the nodes are no longer usable.
This removes all Type uses from effect linearization. There's still some
work to be done for ChangeLowering tho.
R=jarin@chromium.org
Review URL: https://codereview.chromium.org/1908093002
Cr-Commit-Position: refs/heads/master@{#35713}
Instead of using CheckFloatEq and CheckDoubleEq directly, I introduced
a macro which first stores the expected result in a volatile variable.
Here are some comments of previous CLs:
The reason is same as the CL #31808 (issue 1430943002, X87: Change the test case for X87 float operations), please refer: https://codereview.chromium.org/1430943002/.
Here is the key comments from CL #31808
Some new test cases use CheckFloatEq(...) and CheckDoubleEq(...) function for result check. When GCC compiling the CheckFloatEq() and CheckDoubleEq() function,
those inlined functions has different behavior comparing with GCC ia32 build and x87 build.
The major difference is sse float register still has single precision rounding semantic. While X87 register has no such rounding precsion semantic when directly use register value.
The V8 turbofan JITTed has exactly same result in both X87 and IA32 port.
So we add the following sentence to do type cast to keep the same precision for RunCallInt64ToFloat32/RunCallInt64ToFloat64. Such as: volatile double expect = static_cast<float>(*i).
R=titzer@chromium.org, weiliang.lin@intel.com
Review URL: https://codereview.chromium.org/1773513002
Cr-Commit-Position: refs/heads/master@{#34534}
TryTruncateFloat32ToUint64 converts a float32 to a uint64. Additionally it
provides an optional second return value which indicates whether the conversion
succeeded (i.e. float32 value was within uint64 range) or not.
I implemented the new operator on x64, arm64, and mips64. @v8-ppc-ports, can you
please take care of the ppc64 implementation of the second output?
Additionally I fixed a bug on x64 and mips64 in the implementation of
TryTruncateFloat64ToUint64. Cases where the input value was between -1 and 0
were handled incorrectly.
R=titzer@chromium.org, v8-arm-ports@googlegroups.com, v8-mips-ports@googlegroups.com
Review URL: https://codereview.chromium.org/1512023002
Cr-Commit-Position: refs/heads/master@{#32796}
MachineType is now a class with two enum fields:
- MachineRepresentation
- MachineSemantic
Both enums are usable on their own, and this change switches some places from using MachineType to use just MachineRepresentation. Most notably:
- register allocator now uses just the representation.
- Phi and Select nodes only refer to representations.
Review URL: https://codereview.chromium.org/1513543003
Cr-Commit-Position: refs/heads/master@{#32738}
