Re: [PATCH] riscv: Add vectorized binops and insn_expander helpers.

[Robin Dapp <rdapp.gcc@gmail.com>]

> +      machine_mode op2mode = Pmode;
> +      if (inner == E_QImode || inner == E_HImode || inner == E_SImode)
> + op2mode = inner;

This I added in order to match the scalar variants like

  [(set (match_operand:VI_QHS 0 "register_operand"      "=vd,vd, vr, vr")
	(if_then_else:VI_QHS
	  (unspec:<VM>
	    [(match_operand:<VM> 1 "vector_mask_operand" "vm,vm,Wc1,Wc1")
	     (match_operand 5 "vector_length_operand"    "rK,rK, rK, rK")
	     (match_operand 6 "const_int_operand"        " i, i,  i,  i")
	     (match_operand 7 "const_int_operand"        " i, i,  i,  i")
	     (match_operand 8 "const_int_operand"        " i, i,  i,  i")
	     (reg:SI VL_REGNUM)
	     (reg:SI VTYPE_REGNUM)] UNSPEC_VPREDICATE)
	  (any_commutative_binop:VI_QHS
	    (vec_duplicate:VI_QHS
	      (match_operand:<VEL> 4 "reg_or_0_operand"  "rJ,rJ, rJ, rJ"))

Any other way to get there?

> + e.add_input_operand (src2, op2mode == VOIDmode ? GET_MODE (src2) : op2mode);
> Very confusing here.

Hmm I see, the VOIDmode being abused as default might be confusing here.
Would an additional parameter like "bool set_op2_mode" make it clearer?
Another option is to separate this into another function altogether like
emit_len_binop_scalar or so.

> + <BINOP_TO_UPPERCASE> 
> change it into <CODE>

Done and removed the rest.

Thanks.