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  1. 10 Oct, 2016 1 commit
  3. 27 Jun, 2016 1 commit
  5. 04 Feb, 2016 1 commit
    • mtrofin's avatar
      [turbofan] fine grained in-block move optimization · 1ecf58f4
      mtrofin authored 
      So far, we've been moving down gaps wholesale. This change moves
individual move operations instead. This improves some benchmarks,
and should overall reduce code size, because it improves the chance of
reducing the number of moves.

For example, there are improvements on x64 in Emscripten (Bullet, in
particular) , JetStream geomean, Embenchen (zlib).

In the process of making this change, I noticed we can separate the
tasks performed by the move optimizer, as follows:

- group gaps into 1
- push gaps down, jumping instructions (these 2 were together before)
- merge blocks (and then push gaps down)
- finalize

We can do without a finalization list. This avoids duplicating storage -
we already have the list of instructions; it also simplifies the logic, since,
with this change, we may process an instruction's gap twice.

Compile time doesn't regress much (see pathological cases), but we
may want to avoid the allocations of the few sets used in the new code.
I'll do that in a subsequent change.

BUG=

Review URL: https://codereview.chromium.org/1634093002

Cr-Commit-Position: refs/heads/master@{#33715}
      1ecf58f4
  7. 25 Jan, 2016 1 commit
    • mtrofin's avatar
      If all the predecessors of a node have, at the last gap, the exact same · 78b55f2e
      mtrofin authored 
      moves, we move those to the node, and remove them from the
predecessors ("merge" them to the common node).

If only some of the moves are common, we don't do anything. This is
what this change addresses.

The bug linked below should be addressed by this change. The only
difference in codegen before/after the change that introduced the bug
was un-merged moves.

BUG=chromium:549262
LOG=N

Review URL: https://codereview.chromium.org/1527203002

Cr-Commit-Position: refs/heads/master@{#33481}
      78b55f2e
  9. 10 Dec, 2015 1 commit
    • jarin's avatar
      [turbofan] Make MachineType a pair of enums. · bb2a830d
      jarin authored 
      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}
      bb2a830d
  11. 29 Oct, 2015 1 commit
    • mtrofin's avatar
      When we split above an instruction (for example because of splintering), · 46878c1d
      mtrofin authored 
      we may introduce moves that are redundant in the context of
moves on subsequent instructions. Currently, we only detect such
redundancies by allowing moves to skip over Nop instructions (true
nops, with no input/output). We can also skip over other cases, for
example over constant definitions (nop with an output), since whatever
moves happen above it do not influence the instruction's outcome.

We may be able to handle other cases, too - in subsequent CLs.

BUG=

Review URL: https://codereview.chromium.org/1422333003

Cr-Commit-Position: refs/heads/master@{#31662}
      46878c1d
  13. 28 Oct, 2015 1 commit
  15. 27 Oct, 2015 1 commit
    • danno's avatar
      [turbofan] Create ExplicitOperands to specify operands without virtual registers · f1aa5562
      danno authored 
      Up until now, if one wanted to specify an explicit stack location                                                                                                                                                                                                or register as an operand for an instruction, it had to also be
explicitly associated with a virtual register as a so-called
FixedRegister or FixedStackSlot.

For the implementation of tail calls, the plan is to use the gap
resolver needs to shuffle stack locations from the caller to the
tail-called callee. In order to do this, it must be possible to
explicitly address operand locations on the stack that are not
associated with virtual registers.

This CL introduces ExplictOperands, which can specify a specific
register or stack location that is not associated with virtual
register. This will allow tail calls to specify the target
locations for the necessary stack moves in the gap for the tail
call without the core register allocation having to know about
the target of the stack moves at all.

In the process this CL:
* creates a new Operand kind, ExplicitOperand, with which
  instructions can specify register and stack slots without an
  associated virtual register.
* creates a LocationOperand class from which AllocatedOperand and
  ExplicitOperand are derived and provides a common interface to
  get Register, DoubleRegister and spill slot information.
* removes RegisterOperand, DoubleRegisterOperand,
  StackSlotOperand and DoubleStackSlotOperand, they are subsumed
  by LocationOperand.
* addresses a cleanup TODO in AllocatedOperand to reduce the
  redundancy of AllocatedOperand::Kind by using machine_type() to
  determine if an operand corresponds to a general purpose or
  double register.

BUG=v8:4076
LOG=n

Review URL: https://codereview.chromium.org/1389373002

Cr-Commit-Position: refs/heads/master@{#31603}
      f1aa5562
  17. 30 Apr, 2015 1 commit
  19. 29 Apr, 2015 3 commits
  21. 15 Apr, 2015 1 commit
    • dcarney's avatar
      [turbofan] cleanup ParallelMove · 00aec790
      dcarney authored 
      - make ParallelMove into a ZoneVector, removing an annoying level of indirection
- make MoveOperands hold InstructionOperands instead of pointers, so there's no more operand aliasing for moves
- opens up possibility of storing MachineType in allocated operands

R=bmeurer@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1081373002

Cr-Commit-Position: refs/heads/master@{#27842}
      00aec790
  23. 09 Apr, 2015 1 commit
    • dcarney's avatar
      [turbofan] cleanup InstructionOperand a little · 07ff6d9f
      dcarney authored 
      - 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}
      07ff6d9f
  25. 31 Mar, 2015 1 commit
  27. 24 Feb, 2015 1 commit
  29. 06 Feb, 2015 1 commit
  31. 15 Jan, 2015 1 commit
  33. 18 Dec, 2014 1 commit
  35. 17 Dec, 2014 1 commit
  37. 27 Nov, 2014 1 commit