On Thu, 14 Nov 2019 at 20:52, Richard Henderson <richard.hender...@linaro.org> wrote: > Yet another reason why I prefer any semi-hosting call to use an encoding that > is otherwise reserved illegal. > > For this, you have to make up your mind: is it important to execute the > instructions as specified by the ISA, or as specified by the semi-hosting > spec? > > In this case, semi-hosting defines an "entry nop" that begins the sequence, > and > I think that we are well within our rights to ignore the validity of "insn1 > insn2 || other-insn".
Perhaps. I think you get the same issue with insn1 || insn2 vs insn1 || some-other-insn though. (And the spec has wording that explicitly wants the latter to be handled with the normal "I'm a hint instruction" behaviour of insn1.) -- PMM
