Tail calls are matched on the graph, with a dedicated tail call
optimization that is actually testable. The instruction selection can
still fall back to a regular if the platform constraints don't allow to
emit a tail call (i.e. the return locations of caller and callee differ
or the callee takes non-register parameters, which is a restriction that
will be removed in the future).
Also explicitly limit tail call optimization to stubs for now and drop
the global flag.
BUG=v8:4076
LOG=n
Review URL: https://codereview.chromium.org/1114163005
Cr-Commit-Position: refs/heads/master@{#28219}
This introduces a simplified allocation operator which can be used to
model inline allocations in TurboFan. It is currently used for context
allocations, but still disabled because change lowering introduces
floating allocations outside the effect chain that interfere.
R=bmeurer@chromium.org
Review URL: https://codereview.chromium.org/1109773002
Cr-Commit-Position: refs/heads/master@{#28195}
This CL contains the first steps towards tail call optimization:
* Structurally detect tail calls during instruction selection,
looking for special return/call combinations.
* Added new architecture-specific instructions for tail calls which
jump instead of call and take care of frame adjustment.
* Moved some code around.
Currently we restrict tail calls to callees which only use registers
for arguments/return value and to call sites which are explicitly
marked as being OK for tail calls. This excludes, among other things,
call sites in sloppy JS functions and our IC machinery (both need in
general to be able to access the caller's frame).
All this is behind a flag --turbo-tail-calls, which is currently off
by default, so it can easily be toggled.
Review URL: https://codereview.chromium.org/1108563002
Cr-Commit-Position: refs/heads/master@{#28150}
This change aims to introduce the separation of the RegisterAllocator model, using the initial prototype for GreedyAllocator as proof of concept.
Summary:
- new flag, turbo-greedy-regalloc, enabling the new allocator. Default
false.
- initial, untested implementation for the GreedyAllocator.
BUG=
Review URL: https://codereview.chromium.org/1061923005
Cr-Commit-Position: refs/heads/master@{#28018}
Reason for revert:
Breaks Static Initializers test.
http://build.chromium.org/p/client.v8/builders/V8%20Linux64/builds/3210/steps/Static-Initializers/logs/stdio
Original issue's description:
> Introducing the LLVM greedy register allocator.
>
> This change aims to introduce the separation of the RegisterAllocator model,
> using the initial prototype for RegisterAllocatorGreedy as proof of concept.
>
> Summary:
> - new flag, turbo-greedy-regalloc, enabling the new allocator. Default
> false.
> - separated RegisterAllocator into a base type and two derived,
> RegisterAllocatorLinear (the one currently used in TurboFan) and
> RegisterAllocatorGreedy (the new one).
> - initial, untested impementation for the greedy allocator.
>
> BUG=
>
> Committed: https://crrev.com/ec542dea6b6a0cb82d1578a389569d019a59121d
> Cr-Commit-Position: refs/heads/master@{#28015}
TBR=dcarney@chromium.org,titzer@chromium.org,jarin@chromium.org,jvoung@chromium.org,mtrofin@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=
Review URL: https://codereview.chromium.org/1080953006
Cr-Commit-Position: refs/heads/master@{#28017}
This change aims to introduce the separation of the RegisterAllocator model,
using the initial prototype for RegisterAllocatorGreedy as proof of concept.
Summary:
- new flag, turbo-greedy-regalloc, enabling the new allocator. Default
false.
- separated RegisterAllocator into a base type and two derived,
RegisterAllocatorLinear (the one currently used in TurboFan) and
RegisterAllocatorGreedy (the new one).
- initial, untested impementation for the greedy allocator.
BUG=
Review URL: https://codereview.chromium.org/1061923005
Cr-Commit-Position: refs/heads/master@{#28015}
This flag is intended as a staging flag for TurboFan. It serves as a
single flag that always enables a most recent configuration of TurboFan
for test suites and benchmarks, without needing to update test drivers.
R=titzer@chromium.org,machenbach@chromium.org
Review URL: https://codereview.chromium.org/1094573002
Cr-Commit-Position: refs/heads/master@{#27896}
Split interface and implementation of ControlEquivalence and add a
dedicated trace flag --trace-turbo-ceq to make it reusable outside the
scheduler.
R=jarin@chromium.org
Review URL: https://codereview.chromium.org/1056093005
Cr-Commit-Position: refs/heads/master@{#27862}
The cells are stored on prototypes (in their map's PrototypeInfo). When a prototype object changes its map, then both its own validity cell and those of all "downstream" prototypes are invalidated; handlers for a given receiver embed the currently valid cell for that receiver's prototype during their compilation and check it on execution.
Review URL: https://codereview.chromium.org/908213002
Cr-Commit-Position: refs/heads/master@{#27845}
- ConstantOperand was using a too-small field too store its virtual register
- drop ConvertTo, replace it with simple copy
- split AllocatedOperand off from Immediate and Constant to make assignment clearer, also paving the way for small Immediates
- put zone first in *Operand::New
- driveby: drop delayed ssa deconstruction experiment
R=titzer@chromium.org
BUG=
Review URL: https://codereview.chromium.org/1050803002
Cr-Commit-Position: refs/heads/master@{#27692}
Reason for revert:
this indeed drops the max major gc time considerable, so turn it back on
Original issue's description:
> Turn off overapproximation of the weak closure again
>
> As long as we still have to process global handles, the impact is not
> yet worthwhile
>
> BUG=v8:3862
> R=hpayer@chromium.org
> LOG=y
>
> Committed: https://crrev.com/294cdc6aecbd7f76be68217da4b3d35901ebce4b
> Cr-Commit-Position: refs/heads/master@{#27570}
TBR=hpayer@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:3862
Review URL: https://codereview.chromium.org/1068723003
Cr-Commit-Position: refs/heads/master@{#27616}
Reason for revert:
Reverting risky GC changes that block v8 roll.
Original issue's description:
> Reland "Filter invalid slots out from the SlotsBuffer after marking."
>
> > There are two reasons that could cause invalid slots appearance in SlotsBuffer:
> > 1) If GC trims "tail" of an array for which it has already recorded a slots and then migrate another object to the "tail".
> > 2) Tagged slot could become a double slot after migrating of an object to another map with "shifted" fields (for example as a result of generalizing immutable data property to a data field).
>
> > This CL also adds useful machinery that helps triggering incremental write barriers.
>
> > BUG=chromium:454297
> > LOG=Y
>
> NOTRY=true
>
> Committed: https://crrev.com/f86aadd1d45c756467dff8e08a055b462d7a060b
> Cr-Commit-Position: refs/heads/master@{#27433}
TBR=machenbach@chromium.org,ulan@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
Review URL: https://codereview.chromium.org/1041593002
Cr-Commit-Position: refs/heads/master@{#27491}
> There are two reasons that could cause invalid slots appearance in SlotsBuffer:
> 1) If GC trims "tail" of an array for which it has already recorded a slots and then migrate another object to the "tail".
> 2) Tagged slot could become a double slot after migrating of an object to another map with "shifted" fields (for example as a result of generalizing immutable data property to a data field).
> This CL also adds useful machinery that helps triggering incremental write barriers.
> BUG=chromium:454297
> LOG=Y
NOTRY=true
Review URL: https://codereview.chromium.org/1032833002
Cr-Commit-Position: refs/heads/master@{#27433}
Reason for revert:
Need to revert in order to revert https://codereview.chromium.org/1029323003/
Original issue's description:
> Filter invalid slots out from the SlotsBuffer after marking.
>
> There are two reasons that could cause invalid slots appearance in SlotsBuffer:
> 1) If GC trims "tail" of an array for which it has already recorded a slots and then migrate another object to the "tail".
> 2) Tagged slot could become a double slot after migrating of an object to another map with "shifted" fields (for example as a result of generalizing immutable data property to a data field).
>
> This CL also adds useful machinery that helps triggering incremental write barriers.
>
> BUG=chromium:454297
> LOG=Y
>
> Committed: https://crrev.com/5c47c1c0d3e4a488f190c16a64ee02f5a14e6561
> Cr-Commit-Position: refs/heads/master@{#27423}
TBR=hpayer@chromium.org,erik.corry@gmail.com,ishell@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:454297
Review URL: https://codereview.chromium.org/1033453005
Cr-Commit-Position: refs/heads/master@{#27426}
There are two reasons that could cause invalid slots appearance in SlotsBuffer:
1) If GC trims "tail" of an array for which it has already recorded a slots and then migrate another object to the "tail".
2) Tagged slot could become a double slot after migrating of an object to another map with "shifted" fields (for example as a result of generalizing immutable data property to a data field).
This CL also adds useful machinery that helps triggering incremental write barriers.
BUG=chromium:454297
LOG=Y
Review URL: https://codereview.chromium.org/1010363005
Cr-Commit-Position: refs/heads/master@{#27423}