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diff --git a/deps/v8/tools/turbolizer/README.md b/deps/v8/tools/turbolizer/README.md new file mode 100644 index 0000000000..54e1051690 --- /dev/null +++ b/deps/v8/tools/turbolizer/README.md @@ -0,0 +1,62 @@ +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 --turbo --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.
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