search for: x86add_flag

...SDValue maps to a vreg, and "set" does the association between SDValues produced by an SDNode, and vregs produced by the selected instruction. It can set multiple registers (if the last operand produces multiple values). For instance, X86 has things like "[(set GR32:$dst, EFLAGS, (X86add_flag GR32:$src1, GR32:$src2))]" Patterns can't have a root node with a non-void return, because, how would we decide where the return value goes? So, you can basically write two kinds of patterns: - (set <register class>:$dst, <operand>) - (<void-typed operator> <operands&...

Thanks, indeed it was on the LegalizeDAG.cpp and the information proved very useful. I also realized that the customization, promotion or expansion will occur whenever any operand, with the same type as the type specified on the second argument (MVT) of setOperationAction function, appears. (Correct me if I'm wrong). The second doubt I have regards instruction matching. When I define a