Are you planning to allocate a couple of general purpose registers to
represent a double? Do these registers have to be ordered? (e.g. do
you need r_{N}, r_{N+1})Do you want a single build of V8 work both on a hardware that supports real double registers and that does not? If you don't need binary portability then I don't think you need to extend unallocated policies. Just change "interpretation" of DOUBLE_REGISTER policy everywhere. Otherwise, yeah, you need new policies (which would require some bit stealing cause LUnallocated is packed pretty tight already). In any case it would require some adjustments in allocator to get "what interferes with what" right. -- Vyacheslav Egorov On Mon, Aug 13, 2012 at 7:53 AM, Evgeny Baskakov <evgeny.baska...@gmail.com> wrote: > Hi guys, > > I'm looking for ways to modify the Crankshaft compilation mode to make it > work without 64-bit hardware registers. > > Could someone give me brief guidelines? Is it possible at all, without the > whole V8 codebase reworking? > > My first impulse is to extend the LUnallocated policies set and make the > codegen distinguish between single and coupled registers. Then, the lithium > codegen would use the CPU-based code stubs instead of native double-related > instructions. What pitfalls should I be aware of here? > > --Evgeny > > -- > v8-users mailing list > v8-users@googlegroups.com > http://groups.google.com/group/v8-users -- v8-users mailing list v8-users@googlegroups.com http://groups.google.com/group/v8-users
