Messages in this thread | | | Date | Thu, 15 Jan 2009 13:22:14 +0000 (GMT) | From | "Maciej W. Rozycki" <> | Subject | Re: Is 386 processor still supported? |
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On Thu, 15 Jan 2009, Jan-Benedict Glaw wrote:
> * Debian's baseline libc is compiled to use LOCK and some other > newish instructions that are not available on a real i386 CPU.
LOCK dates back to the 8086 -- it has to work with the i386. What is not supported are the following i486 additions: CMPXCHG (amusingly enough early i486 steppings used a different opcode for this one; no idea if it is still possible to find such a CPU), XADD and BSWAP, the latter being fairly unimportant.
> * There was a patch flying around to introduce a kernel-based > emulator for those instructions. However, this was (at that time) > neither included in Debian's kernel, nor in the upstream sources.
UP emulation of CMPXCHG and XADD for userland should be rather trivial, so why not include it like with LL/SC for MIPS?
Maciej
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