Attachment 343430 Details for Bug 186966 – Patch

[patch] Patch

bug-186966-20180623193939.patch (text/plain), 2.28 KB, created by Yusuke Suzuki on 2018-06-23 03:39:40 PDT

(hide)

Description:

Filename:

MIME Type:

Creator: Yusuke Suzuki

Created: 2018-06-23 03:39:40 PDT

Size: 2.28 KB

patch

obsolete

>Subversion Revision: 233123
>diff --git a/Source/bmalloc/ChangeLog b/Source/bmalloc/ChangeLog
>index 8b6caf2c57f800cd0f3572235b59b90a6b21e31b..ced6decf30aac9e6b2b66bb24d915a6294c7eaf0 100644
>--- a/Source/bmalloc/ChangeLog
>+++ b/Source/bmalloc/ChangeLog
>@@ -1,3 +1,29 @@
>+2018-06-23  Yusuke Suzuki  <utatane.tea@gmail.com>
>+
>+        [bmalloc][Linux] Remove static initializers for PerProcess<>::s_object
>+        https://bugs.webkit.org/show_bug.cgi?id=186966
>+
>+        Reviewed by NOBODY (OOPS!).
>+
>+        chrome/tools/linux/dump-static-initializers.py can dump static initializers
>+        in the binary and we found that PerProcess<>::s_object initialization is done
>+        by static initializers in GCC + Linux environments. The example is the following.
>+
>+        Scavenger.cpp (initializer offset 0x38c210 size 0x3e)
>+            _GLOBAL__sub_I_Scavenger.cpp+0x1e
>+            _GLOBAL__sub_I_Scavenger.cpp+0x2d
>+            _GLOBAL__sub_I_Scavenger.cpp+0x3c
>+            _GLOBAL__sub_I_Scavenger.cpp+0xf
>+            guard variable for bmalloc::PerProcess<bmalloc::AllIsoHeaps>::s_object@@Base-0x3f0d8
>+            guard variable for bmalloc::PerProcess<bmalloc::Environment>::s_object@@Base-0x3f0e8
>+            guard variable for bmalloc::PerProcess<bmalloc::PerHeapKind<bmalloc::Heap> >::s_object@@Base-0x3c600
>+            guard variable for bmalloc::PerProcess<bmalloc::Scavenger>::s_object@@Base-0x38ce8
>+
>+        We can remove this by initializing `nullptr`, which leads to constexpr initialization.
>+        After this change, Linux JSCOnly libJavaScriptCore.so has no static initializers.
>+
>+        * bmalloc/PerProcess.h:
>+
> 2018-06-09  Dan Bernstein  <mitz@apple.com>
> 
>         [Xcode] Clean up and modernize some build setting definitions
>diff --git a/Source/bmalloc/bmalloc/PerProcess.h b/Source/bmalloc/bmalloc/PerProcess.h
>index 5a4d49f85711f35babe5997340e629f621635570..d263801578023c1e07052769526f474654e1f8a2 100644
>--- a/Source/bmalloc/bmalloc/PerProcess.h
>+++ b/Source/bmalloc/bmalloc/PerProcess.h
>@@ -123,9 +123,9 @@ class PerProcess {
> };
> 
> template<typename T>
>-std::atomic<T*> PerProcess<T>::s_object;
>+std::atomic<T*> PerProcess<T>::s_object { nullptr };
> 
> template<typename T>
>-PerProcessData* PerProcess<T>::s_data;
>+PerProcessData* PerProcess<T>::s_data { nullptr };
> 
> } // namespace bmalloc

Actions: View | Formatted Diff | Diff

Attachments on bug 186966: 343430