On Sun, Oct 28, 2018 at 01:56:29AM +0000, Richard Henderson wrote: > On 10/27/18 5:37 AM, Stafford Horne wrote: > > +(define_insn "zero_extendhisi2" > > + [(set (match_operand:SI 0 "register_operand" "=r,r") > > + (zero_extend:SI (match_operand:HI 1 "nonimmediate_operand" "r,m")))] > > + "" > > + "@ > > + l.exthz\t%0, %1 > > + l.lhz\t%0, %1" > > + [(set_attr "insn_support" "sext,*")]) > > + > > +(define_insn "zero_extendqisi2" > > + [(set (match_operand:SI 0 "register_operand" "=r,r") > > + (zero_extend:SI (match_operand:QI 1 "nonimmediate_operand" "r,m")))] > > + "" > > + "@ > > + l.extbz\t%0, %1 > > + l.lbz\t%0, %1" > > + [(set_attr "insn_support" "sext,*")]) > > The !sext r/r case is just l.andi.
OK. > > +;; Sign extension patterns > > + > > +;; We can do memory extensions with a single load > > +(define_insn "extendhisi2" > > + [(set (match_operand:SI 0 "register_operand" "=r,r") > > + (sign_extend:SI (match_operand:HI 1 "nonimmediate_operand" "r,m")))] > > + "" > > + "@ > > + l.exths\t%0, %1 > > + l.lhs\t%0, %1" > > + [(set_attr "insn_support" "sext,*")]) > > + > > +(define_insn "extendqisi2" > > + [(set (match_operand:SI 0 "register_operand" "=r,r") > > + (sign_extend:SI (match_operand:QI 1 "nonimmediate_operand" "r,m")))] > > + "" > > + "@ > > + l.extbs\t%0, %1 > > + l.lbs\t%0, %1" > > + [(set_attr "insn_support" "sext,*")]) > > You don't really want to give the register allocator no choice but to spill to > memory in the !sext case. Another r/r case with a splitter that is > conditional > on !sext would work. OK, I was just being lazy allowing the spill. Do you think the split/expand would be an RTL using left shift / right shift? Can you think of something more clever? Since "real" hardware does not usually support shifts with an immediate we will need 1 instruction to load shift amount. i.e. l.ori %0, r0, 24 l.sll %1, %1, %0 l.sra %0, %1, %0 If we support shift with immediate it would just be: l.slli %1, %1, 24 l.srai %0, %1, 24 But, I cant think of anything better. > Otherwise, OK. Thanks, I am submitting patches on my git branch or1k-port-4. Just in case you want to track progress. - Stafford
