lua-users home
lua-l archive

[Date Prev][Date Next][Thread Prev][Thread Next] [Date Index] [Thread Index]

Hi Mike:

Thanks for your quick response. It indeed looks like SSE is not enabled in the kernel per:

$ sysctl hw.instruction_sse
hw.instruction_sse: 0

However, this is a production kernel, for which any changes need to go thru a time-consuming QA process, as well as requiring me to run the gauntlet of fascist system administration :-( Under the circumstances, I would prefer to take the performance hit by sinking back into the pre-SSE days. I didn't see any option for disabling the use of SSE in the Luajit code - can this be done via a define? Alternatively, is there some way to detect that although the CPU supports SSE, the kernel doesn't, and dynamically disable that code under the circumstances?

Thanks in advance.

Mike Pall wrote:

Jim Mellander wrote:

I've been using Luajit 1.0.3 for my application with no problems on FreeBSD 4.10

I built LuaJIT 1.1.0 ('make bsd') on the same system, and get the following problem:
Illegal instruction (core dumped)

This looks like a problem with SSE2 code generation. It seems
your kernel doesn't know how to deal with it even though your CPU
supports it?

I don't have access to a system with such an old version of
FreeBSD. But a little research shows that SSE support must be
explicitly enabled for 4.x with 'options CPU_ENABLE_SSE'. If your
kernel doesn't have this, then you need to recompile it with this


Jim Mellander
Incident Response Manager
Computer Protection Program
Lawrence Berkeley National Laboratory
(510) 486-7204

Your fortune for today is:

Let us never negotiate out of fear, but let us never fear to negotiate.
		-- John F. Kennedy