8d921ca7f3
This removes the --turbo flag and solely relies on the filter pattern
provided via --turbo-filter when deciding whether to use TurboFan. Note
that disabling optimization wholesale can still be done with --no-opt,
which should be used in favor of --no-turbo everywhere.
Also note that this contains semantic changes to the TurboFan activation
criteria. We respect the filter pattern more stringently and no longer
activate TurboFan just because the source contains patterns forcing use
of Ignition via {AstNumberingVisitor::DisableFullCodegenAndCrankshaft}.
R=rmcilroy@chromium.org
BUG=v8:6408
Change-Id: I0c855f6a62350eb62283a3431c8cc1baa750950e
Reviewed-on: https://chromium-review.googlesource.com/528121
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46167}
63 lines
2.8 KiB
Markdown
63 lines
2.8 KiB
Markdown
Turbolizer
|
|
==========
|
|
|
|
Turbolizer is a HTML-based tool that visualizes optimized code along the various
|
|
phases of Turbofan's optimization pipeline, allowing easy navigation between
|
|
source code, Turbofan IR graphs, scheduled IR nodes and generated assembly code.
|
|
|
|
Turbolizer consumes .json files that are generated per-function by d8 by passing
|
|
the '--trace-turbo' command-line flag.
|
|
|
|
Host the turbolizer locally by starting a web server that serves the contents of
|
|
the turbolizer directory, e.g.:
|
|
|
|
cd src/tools/turbolizer
|
|
python -m SimpleHTTPServer 8000
|
|
|
|
Optionally, profiling data generated by the perf tools in linux can be merged
|
|
with the .json files using the turbolizer-perf.py file included. The following
|
|
command is an example of using the perf script:
|
|
|
|
perf script -i perf.data.jitted -s turbolizer-perf.py turbo-main.json
|
|
|
|
The output of the above command is a json object that can be piped to a file
|
|
which, when uploaded to turbolizer, will display the event counts from perf next
|
|
to each instruction in the disassembly. Further detail can be found in the
|
|
bottom of this document under "Using Perf with Turbo."
|
|
|
|
Using the python interface in perf script requires python-dev to be installed
|
|
and perf be recompiled with python support enabled. Once recompiled, the
|
|
variable PERF_EXEC_PATH must be set to the location of the recompiled perf
|
|
binaries.
|
|
|
|
Graph visualization and manipulation based on Mike Bostock's sample code for an
|
|
interactive tool for creating directed graphs. Original source is at
|
|
https://github.com/metacademy/directed-graph-creator and released under the
|
|
MIT/X license.
|
|
|
|
Icons derived from the "White Olive Collection" created by Breezi released under
|
|
the Creative Commons BY license.
|
|
|
|
Using Perf with Turbo
|
|
---------------------
|
|
|
|
In order to generate perf data that matches exactly with the turbofan trace, you
|
|
must use either a debug build of v8 or a release build with the flag
|
|
'disassembler=on'. This flag ensures that the '--trace-turbo' will output the
|
|
necessary disassembly for linking with the perf profile.
|
|
|
|
The basic example of generating the required data is as follows:
|
|
|
|
perf record -k mono /path/to/d8 --trace-turbo --perf-prof main.js
|
|
perf inject -j -i perf.data -o perf.data.jitted
|
|
perf script -i perf.data.jitted -s turbolizer-perf.py turbo-main.json
|
|
|
|
These commands combined will run and profile d8, merge the output into a single
|
|
'perf.data.jitted' file, then take the event data from that and link them to the
|
|
disassembly in the 'turbo-main.json'. Note that, as above, the output of the
|
|
script command must be piped to a file for uploading to turbolizer.
|
|
|
|
There are many options that can be added to the first command, for example '-e'
|
|
can be used to specify the counting of specific events (default: cycles), as
|
|
well as '--cpu' to specify which CPU to sample.
|