disas/riscv: Tidy decode of mop.r.n and mop.rr.n
Merge nested if's. Reuse operand_mop_{r,rr}_imm for zicfiss decode. Return pointers directly. Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org> Message-ID: <20260812223142.349142-51-richard.henderson@linaro.org> Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Richard Henderson committed
Aug 12, 2026 at 15:31 UTC
ef25a26b7dc29ba4b78a70d22a6a806dd4637537
1 file changed
+24
-35
disas/riscv.c
+24
-35
@@ -2555,44 +2555,33 @@ static const rv_opcode_data *decode_inst_opcode(rv_decode *dec, rv_isa isa)
2555
case 3: op = rv_op_csrrc; break;
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case 4:
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if (dec->cfg && dec->cfg->ext_zimop) {
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- int imm_mop5, imm_mop3, reg_num;
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- if ((extract32(inst, 22, 10) & 0b1011001111)
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- == 0b1000000111) {
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- imm_mop5 = deposit32(deposit32(extract32(inst, 20, 2),
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- 2, 2,
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- extract32(inst, 26, 2)),
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- 4, 1, extract32(inst, 30, 1));
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- op = rv_op_mop_r;
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- /* if zicfiss enabled and mop5 is shadow stack */
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- if (dec->cfg->ext_zicfiss &&
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- ((imm_mop5 & 0b11100) == 0b11100)) {
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- /* rs1=0 means ssrdp */
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- if ((inst & (0b011111 << 15)) == 0) {
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- op = rv_op_ssrdp;
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- }
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- /* rd=0 means sspopchk */
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- reg_num = (inst >> 15) & 0b011111;
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- if (((inst & (0b011111 << 7)) == 0) &&
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- ((reg_num == 1) || (reg_num == 5))) {
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- op = rv_op_sspopchk;
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+ if (((inst >> 22) & 0b1011001111) == 0b1000000111) {
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+ if (dec->cfg->ext_zicfiss
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+ && operand_mop_r_imm(inst) == 28) {
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+ switch (operand_rs1(inst)) {
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+ case 0:
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+ return &rvi_opcode_data[rv_op_ssrdp];
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+ case 1:
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+ case 5:
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+ if (operand_rd(inst) == 0) {
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+ return &rvi_opcode_data[rv_op_sspopchk];
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}
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+ }
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}
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- } else if ((extract32(inst, 25, 7) & 0b1011001)
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- == 0b1000001) {
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- imm_mop3 = deposit32(extract32(inst, 26, 2),
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- 2, 1, extract32(inst, 30, 1));
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- op = rv_op_mop_rr;
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- /* if zicfiss enabled and mop3 is shadow stack */
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- if (dec->cfg->ext_zicfiss &&
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- ((imm_mop3 & 0b111) == 0b111)) {
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- /* rs1=0 and rd=0 means sspush */
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- reg_num = (inst >> 20) & 0b011111;
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- if (((inst & (0b011111 << 15)) == 0) &&
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- ((inst & (0b011111 << 7)) == 0) &&
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- ((reg_num == 1) || (reg_num == 5))) {
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- op = rv_op_sspush;
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- }
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+ return &rvi_opcode_data[rv_op_mop_r];
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+ }
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+ if (((inst >> 25) & 0b1011001) == 0b1000001) {
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+ if (dec->cfg->ext_zicfiss
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+ && operand_mop_rr_imm(inst) == 7
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+ && operand_rd(inst) == 0
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+ && operand_rs1(inst) == 0) {
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+ switch (operand_rs2(inst)) {
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+ case 1:
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+ case 5:
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+ return &rvi_opcode_data[rv_op_sspush];
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+ }
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}
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+ return &rvi_opcode_data[rv_op_mop_rr];
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}
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}
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break;