On Dec 10, 2013, at 2:12 PM, H.J. Lu <hjl.to...@gmail.com> wrote: > On Tue, Dec 10, 2013 at 11:05 AM, Tejas Belagod <tbela...@arm.com> wrote: >> ... >> So, if (subreg:DI (match_operand:V4SF 1 "register_operand" "x,x") 0) is a >> valid subreg, why not allow it in CANNOT_CHANGE_MODE_CLASS (like in Kirill's >> patch http://gcc.gnu.org/ml/gcc-patches/2013-12/msg00987.html) and resolve >> the actual register later in subreg_get_info ()? > > Let's wait for Kirill's results on GCC testsuite.
I'm puzzled. What is the connection between testsuite results and a design decision about a code change? The question remains valid even if the testsuite didn't exist at all. paul