[PATCH 1/2] RISC-V: Support extension Zicfiss and Zicfilp

[Jan Beulich]

On 10.01.2025 11:17, Kito Cheng wrote:
> --- a/opcodes/riscv-opc.c
> +++ b/opcodes/riscv-opc.c
> @@ -381,15 +381,46 @@ match_cm_jalt (const struct riscv_opcode *op, insn_t insn)
>      && EXTRACT_ZCMT_INDEX (insn) < 256;
>  }
>  
> -/* The order of overloaded instructions matters.  Label arguments and
> -   register arguments look the same. Instructions that can have either
> -   for arguments must apear in the correct order in this table for the
> -   assembler to pick the right one. In other words, entries with
> -   immediate operands must apear after the same instruction with
> -   registers.
>  
> -   Because of the lookup algorithm used, entries with the same opcode
> -   name must be contiguous.  */

I don't think this comment should be removed.

> +static int
> +match_rs1_x1x5_opcode (const struct riscv_opcode *op,
> +                      insn_t insn)
> +{
> +  int rs1 = (insn & MASK_RS1) >> OP_SH_RS1;
> +  return match_opcode (op, insn) && (rs1 == 1 || rs1 == 5);
> +}
> +
> +static int
> +match_rs2_x1x5_opcode (const struct riscv_opcode *op,
> +                      insn_t insn)
> +{
> +  int rs2 = (insn & MASK_RS2) >> OP_SH_RS2;
> +  return match_opcode (op, insn) && (rs2 == 1 || rs2 == 5);
> +}
> +
> +static int
> +match_c_mop_1 (const struct riscv_opcode *op,
> +               insn_t insn)
> +{
> +  int n = EXTRACT_C_MOP_N (insn) ;
> +  return match_opcode (op, insn) && n == 1;
> +}
> +
> +static int
> +match_c_mop_5 (const struct riscv_opcode *op,
> +               insn_t insn)
> +{
> +  int n = EXTRACT_C_MOP_N (insn) ;
> +  return match_opcode (op, insn) && n == 5;
> +}
> +
> +static int
> +match_rd_x1x5_opcode (const struct riscv_opcode *op,
> +                     insn_t insn)
> +{
> +  int rd = (insn & MASK_RD) >> OP_SH_RD;
> +  return match_opcode (op, insn) && (rd == 1 || rd == 5);
> +}
>  
>  const struct riscv_opcode riscv_opcodes[] =
>  {
> @@ -546,6 +577,10 @@ const struct riscv_opcode riscv_opcodes[] =
>  {"or",          0, INSN_CLASS_C, "Cs,Cw,Ct",  MATCH_C_OR, MASK_C_OR, match_opcode, INSN_ALIAS },
>  {"or",          0, INSN_CLASS_C, "Cs,Ct,Cw",  MATCH_C_OR, MASK_C_OR, match_opcode, INSN_ALIAS },
>  {"or",          0, INSN_CLASS_I, "d,s,t",     MATCH_OR, MASK_OR, match_opcode, 0 },
> +
> +/* Zicfilp instructions.  */
> +{"lpad",        0, INSN_CLASS_ZICFILP, "u", MATCH_LPAD, MASK_LPAD, match_opcode, 0 },

Can the MATCH_* please be padded enough to match adjacent table entries?

Jan