[Webkit-unassigned] [Bug 94712] High memory usage spike in AssemblerBuffer

bugzilla-daemon at webkit.org bugzilla-daemon at webkit.org
Mon Aug 27 16:52:11 PDT 2012


https://bugs.webkit.org/show_bug.cgi?id=94712





--- Comment #25 from Gavin Barraclough <barraclough at apple.com>  2012-08-27 16:52:13 PST ---
> I tried making X86Assmebler work with the new AssemblerBuffer. But there are too many dependencies on the flat consecutive buffer. I guess probably more than half of the source code will be changed.

I'd suggest there is probably a really quick fix you could try here.  In the X86Assembler, do two quick find & replaces to remove the following:
    "m_buffer.ensureSpace(maxInstructionSize);" -> ""
    "Unchecked" -> ""
This will add a few extra bounds checks, but the benefit from your patch should more than balance this out.

> Speaking of assemblers, there is already another AssemblerBuffer for ARM (traditional): AssemblerBufferWithConstantPool.

No, ARM doesn't use a different AssemblerBuffer – if you look you'll see that AssemblerBufferWithConstantPool is actually a subclass of AssemblerBuffer – all assemblers use the same implementation of AssemblerBuffer, we just happen to use inheritance as a part of how we structure the code to share the constant pool used by ARM traditional & SH4.

-- 
Configure bugmail: https://bugs.webkit.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.


More information about the webkit-unassigned mailing list