ddb2856f39
Previously when we put offsets into the SourcePositionTable, we added the header size of the code object as well. When we pull the positions out of the table (see ProfileGenerator::RecordTickSample) we already account for the header size. This means the offsets in the table should just be the offset of the PC within the actual code, not the offset within the code object, which is what we currently store. Currently this bug is probably not very noticeable, as it causes the reported line numbers to be slightly too low, but still within the same function. For a sampling profiler, we don't have any way to confirm which lines were actually sampled, so we don't notice that the results are wrong. The only way to see this bug is that there are some lines within a function (towards the end of the function) that we will never see ticks inside of, because the offset in the position table is not reachable with valid PC offsets. This CL removes the header size offset from values put into the source position table stored by the profiler. Bug: v8:7018 Change-Id: I00b17cec5f9c81d993d4e64c3c021052745a791e Reviewed-on: https://chromium-review.googlesource.com/1016560 Reviewed-by: Jakob Gruber <jgruber@chromium.org> Reviewed-by: Yang Guo <yangguo@chromium.org> Commit-Queue: Peter Marshall <petermarshall@chromium.org> Cr-Commit-Position: refs/heads/master@{#52671} |
||
|---|---|---|
| benchmarks | ||
| build_overrides | ||
| docs | ||
| gni | ||
| include | ||
| infra | ||
| samples | ||
| src | ||
| test | ||
| testing | ||
| third_party | ||
| tools | ||
| .clang-format | ||
| .editorconfig | ||
| .git-blame-ignore-revs | ||
| .gitignore | ||
| .gn | ||
| .vpython | ||
| .ycm_extra_conf.py | ||
| AUTHORS | ||
| BUILD.gn | ||
| ChangeLog | ||
| CODE_OF_CONDUCT.md | ||
| codereview.settings | ||
| DEPS | ||
| LICENSE | ||
| LICENSE.fdlibm | ||
| LICENSE.strongtalk | ||
| LICENSE.v8 | ||
| LICENSE.valgrind | ||
| OWNERS | ||
| PRESUBMIT.py | ||
| README.md | ||
| snapshot_toolchain.gni | ||
| 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://github.com/v8/v8/wiki
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 on the V8 wiki.