d8a32a96e3
Instead of having a loop with one big switch for handling the different
opcodes, split the decoding into one handler per opcode and call them
via an opcode handler table.
The compiler will generate similar code for this new approach (the big
switch is also compiled into a table lookup and an indirect jump). The
main difference is that it's now calls instead of jumps. This has a
slight performance impact, but allows to look at the decoding logic of
individual opcodes in isolation and see optimization opportunities much
easier. It also allows spot very easily in profilers on which opcodes
most time is spent.
The different opcode handlers are still implemented via the same switch
as before, but since the opcode is a template argument (hence static)
the compiler will eliminate the switch and generate the small handlers
we want.
I plan to actually remove the switch and break up the big generic
{DecodeOp} method into one method per opcode.
R=thibaudm@chromium.org
Bug: v8:10576
Change-Id: Ic2c1e2fe5e98df52a7079ace305cf77340dcbf35
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2249664
Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68403}
|
||
|---|---|---|
| build_overrides | ||
| custom_deps | ||
| docs | ||
| gni | ||
| include | ||
| infra | ||
| samples | ||
| src | ||
| test | ||
| testing | ||
| third_party | ||
| tools | ||
| .clang-format | ||
| .clang-tidy | ||
| .editorconfig | ||
| .flake8 | ||
| .git-blame-ignore-revs | ||
| .gitattributes | ||
| .gitignore | ||
| .gn | ||
| .vpython | ||
| .ycm_extra_conf.py | ||
| AUTHORS | ||
| BUILD.gn | ||
| CODE_OF_CONDUCT.md | ||
| codereview.settings | ||
| COMMON_OWNERS | ||
| DEPS | ||
| ENG_REVIEW_OWNERS | ||
| INFRA_OWNERS | ||
| INTL_OWNERS | ||
| LICENSE | ||
| LICENSE.fdlibm | ||
| LICENSE.strongtalk | ||
| LICENSE.v8 | ||
| LICENSE.valgrind | ||
| MIPS_OWNERS | ||
| OWNERS | ||
| PPC_OWNERS | ||
| PRESUBMIT.py | ||
| README.md | ||
| S390_OWNERS | ||
| WATCHLISTS | ||
V8 JavaScript Engine
V8 is Google's open source JavaScript engine.
V8 implements ECMAScript as specified in ECMA-262.
V8 is written in C++ and is used in Google Chrome, the open source browser from Google.
V8 can run standalone, or can be embedded into any C++ application.
V8 Project page: https://v8.dev/docs
Getting the Code
Checkout depot tools, and run
fetch v8
This will checkout V8 into the directory v8 and fetch all of its dependencies.
To stay up to date, run
git pull origin
gclient sync
For fetching all branches, add the following into your remote
configuration in .git/config:
fetch = +refs/branch-heads/*:refs/remotes/branch-heads/*
fetch = +refs/tags/*:refs/tags/*
Contributing
Please follow the instructions mentioned at v8.dev/docs/contribute.