On 17/10/11 17:20, Andrew Pinski wrote:
On Mon, Oct 17, 2011 at 3:50 AM, Paulo J. Matos<pa...@matos-sorge.com> wrote:addc_internal looks like: (define_insn "addc_internal" [(set (match_operand:QI 0 "nonimmediate_operand" "=c") (plus:QI (plus:QI (ltu:QI (reg:CC RCC) (const_int 0)) (match_operand:QI 1 "nonimmediate_operand" "%0")) (match_operand:QI 2 "general_operand" "cwmi"))) (clobber (reg:CC RCC))] "" "addc\\t%0,%f2")Try adding (use (reg:CC RCC)) to the pattern above.
Currently compiling that change into the code. I have a feeling that it will either confuse compare-elim.c or that it will be too strict and remove any possibility of optimization since with (use (reg:CC RCC)) we are not really saying that we are only interested in the carry flag instead of the whole thing. It will avoid anything clobbering RCC which is most of the instructions.
I will give it a spin and see what actually happens. Thanks, -- PMatos
