2013/6/3 Jeff Law <l...@redhat.com>: > On 06/03/2013 11:00 AM, Richard Henderson wrote: >> >> On 06/03/2013 09:37 AM, Kai Tietz wrote: >>> >>> foo: >>> .seh_endprologue >>> cmpb %cl, %dl >>> seta %al >>> ret >>> .seh_endproc >>> .p2align 4,,15 >>> .globl boo >>> .def boo; .scl 2; .type 32; .endef >>> .seh_proc boo >>> boo: >>> .seh_endprologue >>> movl %ecx, %eax >>> notl %eax >>> andl %edx, %eax >>> andl $1, %eax >>> ret >> >> >> Try arm or s390 or ppc for significantly different results. > > I'm starting to wonder if we could delay make a choice about using a > relational or bit ops until gimple->rtl expansion. I haven't seen any > secondary benefits, so deferring to a later point where we might be able to > query the backend's capabilities might make sense. > jeff
Well, a secondary benefit I see in area of BC-optimization. But I agree that this operation should go along gimple->rtl transformation. And at same place BC-optimization should happen. Kai
