hjl.tools added a comment. In D99708#2664372 <https://reviews.llvm.org/D99708#2664372>, @craig.topper wrote:
> In D99708#2664351 <https://reviews.llvm.org/D99708#2664351>, @hjl.tools wrote: > >> In D99708#2664218 <https://reviews.llvm.org/D99708#2664218>, @craig.topper >> wrote: >> >>> In D99708#2664164 <https://reviews.llvm.org/D99708#2664164>, @hjl.tools >>> wrote: >>> >>>> In D99708#2664076 <https://reviews.llvm.org/D99708#2664076>, @LuoYuanke >>>> wrote: >>>> >>>>> In D99708#2663989 <https://reviews.llvm.org/D99708#2663989>, >>>>> @craig.topper wrote: >>>>> >>>>>> A user interrupt is different than a regular interrupt right? It doesn't >>>>>> make sense that we would change the behavior of the interrupt calling >>>>>> convention just because the the user interrupt instructions are enabled. >>>>>> That would occur just from passing a -march for a newer CPU wouldn't it? >>>>> >>>>> Maybe need support another attribute "__attribute__ ((user_interrupt))" >>>>> for functions? However this is what gcc does >>>>> (https://gcc.godbolt.org/z/8ojTMG6bT). >>>> >>>> Since there won't be both user interrupt handler and kernel interrupt >>>> handler in the source, there is no need for another >>>> attribute. We discussed that kernel might need to use UINTR >>>> instructions. We decided that kernel could use inline asm >>>> statements if needed. >>> >>> So if write kernel code and compile with -march=haswell today, I get IRET. >>> If tomorrow I change my command line to -march=sapphirerapids, now my >>> kernel interrupt code generates user interrupt instructions. That seems >>> surprising. >> >> -mcmodel=kernel should disable uiret.: >> >> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99870 > > That makes sense. Can we put that in this patch? The feedback is that don't enable UINTR for kernel build. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D99708/new/ https://reviews.llvm.org/D99708 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
