A user reported this crash with WebKitGTK 2.30.5 after opening www.avito.ru , selecting "Вход и регистрация" on the upper right corner and simply waiting for a few seconds. (gdb) layout asm >│0x7f00eb999254 <wasm_entry+56936> roundss $0x2,%xmm0,%xmm1 │ │0x7f00eb99925a <wasm_entry+56942> movsbq 0x1(%r13,%r8,1),%r9 │ │0x7f00eb999260 <wasm_entry+56948> movss %xmm1,0x0(%rbp,%r9,8) │ │0x7f00eb999267 <wasm_entry+56955> add $0x3,%r8 │ This is a 64-bit build but the CPU is an old Intel Core 2 without SSE4 instructions. Disabling the JIT ("JavaScriptCoreUseJIT=0") seems to solve the problem. I assume that there is no plan to support such old hardware, but is this simply a WONTFIX or should WebKit disable the JIT conditionally in these cases?
<rdar://problem/75363426>
Is this a duplicate of bug #222358?
(In reply to Alberto Garcia from comment #0) > should WebKit disable the JIT conditionally in these cases? That would be ideal.
*** Bug 222358 has been marked as a duplicate of this bug. ***
Can we just disable JIT when SSE4 is not available?
JSC_useBaselineJIT=0 also fixes it for me. I have that exported in my environment .
(In reply to Carlos Garcia Campos from comment #5) > Can we just disable JIT when SSE4 is not available? Please, though I'm not sure how to test for that easily. I checked and Fedora's baseline is SSE2. I guess Debian's is probably the same, so we would want to check for SSE3 really.
(In reply to Michael Catanzaro from comment #7) > I checked and Fedora's baseline is SSE2. I guess Debian's is probably the > same, so we would want to check for SSE3 really. It is, according to https://wiki.debian.org/ArchitectureSpecificsMemo#amd64: "x86_64 with no optional extensions. The core specification includes MMX, SSE and SSE2 so these are OK, but SSE3 and up are not guaranteed."
This issue is basically the same as bug #220889 and there is a patch there with review feedback, so let's treat this one as the duplicate. *** This bug has been marked as a duplicate of bug 220889 ***
Well, one possibility not contemplated in bug #220889 would be to automatically disable the JIT if the system does not support SSE4. If somebody wants to attempt that, we could reopen this one.