Display register allocation live ranges alongside sequences in
turbolizer.
The existing --trace-turbo flag now also outputs the register
allocation data as part of the json file alongside the
instruction sequence data that is already produced before and
after register allocation is performed. This data includes live
range intervals for each virtual and fixed register and the state
of their assignments.
This json data can now be displayed in turbolizer alongside the
instruction sequences. The information is presented as a grid,
with each grid cell representing a LifeTimePosition of a certain
virtual register, determined by the column and row indices
respectively. Each LifeTimePosition is shown to be part of an
instruction id which itself is shown to be part of a block id.
Each interval is shown as a coloured rectangle positioned over
the relevant cells, and displaying text to indicate the state of
their assignment.
The Resizer object has been extended to allow the grid's html
panel to be varied in size in the same manner that the left and
right panels can be. The size of the grid itself must also be
adjusted whenever the div container changes size.
The RangeView class is introduced and is created and held by the
single SequenceView object used to display the
InstructionSequence data before and after register allocation.
A checkbox allows the user to show/hide the range view, this is
disabled when register allocation data is not provided or more
than 249 instructions are in the sequence. The latter being
required due to the css grid-row-col limit of 1000 alond with
helping alleviate performance issues. The SequenceView object
tracks the phase index currently selected as well as whether or
not it is currently being shown. This ensures that the RangeView
is not hidden and shown when switching between before and after
register allocation, allowing for a smoother transition between
the two. The scroll position is also saved and restored for
convenience.
The data about the instruction sequence required for the display
is held by the RangeView object and reset whenever a new
instruction sequence is shown. The grid div must sync its scroll
with the headers and row labels so as to ensure a consistent
view. The register allocation data is extracted from the json,
with each register row showing all intervals within the relevant
ranges. When the view is switched between before and after
register allocation, the relevant intervals are swapped in.
Bug: v8:7327
Notry: true
Change-Id: I183535a2410a7d663382f387199885250fb98691
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2184232
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Santiago Aboy Solanes <solanes@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68019}
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