On 07/04/2013 03:53 AM, Peter Maydell wrote: > On 3 July 2013 22:29, Richard Henderson <r...@twiddle.net> wrote: >> This allows TCG_TARGET_HAS_* to be a variable rather than a constant, >> which allows easier support for differing ISA levels for the host. > > The effect of this is that TCG_OPF_NOT_PRESENT means "if set, > op is definitely not present; if not set, op might or might > not be present", right? Which is OK because it's just a debug > guard/sanity check. (That might be worth noting in a comment > I guess.)
Well, if not set, an entry must be present in the operands table. E.g. for arm division, the { INDEX_op_div_i32, "r", "r", "r" } entry is always there, even if TCG_TARGET_HAS_div_i32 evaluates to false at runtime. The entry must be there Just In Case the expression might be true. r~