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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Oct 10, 2022, at 11:23 PM, Nick Desaulniers wrote: > On Sat, Jul 16, 2022 at 2:47 AM Arnd Bergmann wrote: >> On Sat, Jul 16, 2022 at 2:16 AM Nick Desaulniers wrote: > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm/nwfpe/softfloat.c#n2312 > Any creative ideas on how to avoid this? Perhaps putting the `aSig -= > bSig;` in inline asm? Inserting a `barrier()` or empty asm statement > into the loops also seems to work. I was going to suggest adding a barrier() as well, should have read on first ;-) > I see this function seems to be based on Berkeley Softfloat > http://www.jhauser.us/arithmetic/SoftFloat.html > v2. v3 looks like a total rewrite. Looking at v3e, it looks like > float64_rem() is now called f64_rem() and defined in f64_rem.c. It > doesn't look like there's anything from v3 that we could backport to > the kernel's v2 to avoid this. > > Otherwise perhaps we just disable OABI_COMPAT for clang. Quite a few > defconfigs explicitly enable FPE_NWFPE though. Are there really a lot > of OABI binaries still in use? I'd do the minimal thing here, neither NWFPE nor OABI_COMPAT should be too relevant here. Russell still uses some machines with old OABI binaries, but I have not heard from anyone else using those in a very long time. Note that while gcc can still produce kernels that are OABI binaries, gcc-4.6 marked the arm-linux-gnu target as obsolete and gcc-4.8 removed it, so any existing binaries were built with toolchains predating that. Arnd _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel