[Webkit-unassigned] [Bug 169882] New: WebAssembly: allocate no more than 4GiB for Signaling memory

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=169882

            Bug ID: 169882
           Summary: WebAssembly: allocate no more than 4GiB for Signaling
                    memory
    Classification: Unclassified
           Product: WebKit
           Version: WebKit Nightly Build
          Hardware: Unspecified
                OS: Unspecified
            Status: NEW
          Severity: Normal
          Priority: P2
         Component: JavaScriptCore
          Assignee: webkit-unassigned at lists.webkit.org
          Reporter: jfbastien at apple.com
                CC: fpizlo at apple.com, jfbastien at apple.com,
                    keith_miller at apple.com, mark.lam at apple.com,
                    msaboff at apple.com, sbarati at apple.com
            Blocks: 159775

We currently virtually allocate 8GiB because odd corner cases potentially allow accesses to go above 4GiB. Those would always trap, so we need the memory to be mapped. This lowers the number of "fast" signaling memory we can allocate, it would be better to figure out which accesses could go above 4GiB, bounds check those, and all the other ones can stay entirely unchecked.

Note: maybe we want 4GiB + some small redzone for small offsets.

-- 
You are receiving this mail because:
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.webkit.org/pipermail/webkit-unassigned/attachments/20170320/0b18e60b/attachment.html>