Hi, I am trying to understand predicate and constraints. To this end, I created a simple define_insn : (define_insn "movqi" [(set (match_operand:QI 0 "nonimmediate_operand" "=r,r,m,r,r,>,<,r") (match_operand:QI 1 "general_operand" "r,m,r,>,<,r,r,i"))] "" "@ move.b %0,%1; <movqi reg := reg> move.b %0,%1; <movqi reg := mem> move.b %0,%1; <movqi mem := reg> move.b %0,%1; <movqi reg := mem with autoincrement> move.b %0,%1; <movqi reg := mem with autodecrement> move.b %0,%1; <movqi mem with autoincrement := reg> move.b %0,%1; <movqi mem with autodecrement := reg> move.b %0,%1; <movqi reg := const>") My questions are: 1) How '>' really work, am i using it correctly or do I need to use it with another another constraint (like 'm>')? 1.1) Which file should I load while debugging to understand how constrains are being use? 2) How I limit the 'i' constraint so that only constants below or equal to 255 are allowed? Thanks in advance for your help! Regards, -Omar
