disas/riscv: Handle aliases of csrrw during decode
Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org> Message-ID: <20260812223142.349142-23-richard.henderson@linaro.org> Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Richard Henderson committed
Aug 12, 2026 at 15:31 UTC
b1d5cbf56abc5604c6848350926271e7f865f988
1 file changed
+9
-13
disas/riscv.c
+9
-13
@@ -1081,9 +1081,6 @@ static const rvc_constraint rvcc_frrm[] = { rvc_rs1_eq_x0, rvc_csr_eq_0x002,
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rvc_end };
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static const rvc_constraint rvcc_frflags[] = { rvc_rs1_eq_x0, rvc_csr_eq_0x001,
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rvc_end };
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-static const rvc_constraint rvcc_fscsr[] = { rvc_csr_eq_0x003, rvc_end };
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-static const rvc_constraint rvcc_fsrm[] = { rvc_csr_eq_0x002, rvc_end };
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-static const rvc_constraint rvcc_fsflags[] = { rvc_csr_eq_0x001, rvc_end };
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static const rvc_constraint rvcc_fsrmi[] = { rvc_csr_eq_0x002, rvc_end };
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static const rvc_constraint rvcc_fsflagsi[] = { rvc_csr_eq_0x001, rvc_end };
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@@ -1166,14 +1163,6 @@ static const rv_comp_data rvcp_subw[] = {
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{ rv_op_illegal, NULL }
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};
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-static const rv_comp_data rvcp_csrrw[] = {
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- { rv_op_fscsr, rvcc_fscsr },
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- { rv_op_fsrm, rvcc_fsrm },
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- { rv_op_fsflags, rvcc_fsflags },
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- { rv_op_illegal, NULL }
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-};
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-
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-
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static const rv_comp_data rvcp_csrrs[] = {
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{ rv_op_rdcycle, rvcc_rdcycle },
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{ rv_op_rdtime, rvcc_rdtime },
@@ -1761,7 +1750,7 @@ static const rv_opcode_data rvi_opcode_data[] = {
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{ "sfence.vm", rv_codec_r, rv_fmt_rs1 },
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{ "sfence.vma", rv_codec_r, rv_fmt_rs1_rs2 },
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{ "wfi", rv_codec_none, rv_fmt_none },
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- { "csrrw", rv_codec_i_csr, rv_fmt_rd_csr_rs1, rvcp_csrrw },
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+ { "csrrw", rv_codec_i_csr, rv_fmt_rd_csr_rs1 },
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{ "csrrs", rv_codec_i_csr, rv_fmt_rd_csr_rs1, rvcp_csrrs },
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{ "csrrc", rv_codec_i_csr, rv_fmt_rd_csr_rs1 },
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{ "csrrwi", rv_codec_i_csr, rv_fmt_rd_csr_zimm, rvcp_csrrwi },
@@ -4443,7 +4432,14 @@ static void decode_inst_opcode(rv_decode *dec, rv_isa isa)
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break;
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}
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break;
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- case 1: op = rv_op_csrrw; break;
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+ case 1:
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+ switch (operand_csr12(inst)) {
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+ case 1: op = rv_op_fsflags; break;
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+ case 2: op = rv_op_fsrm; break;
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+ case 3: op = rv_op_fscsr; break;
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+ default: op = rv_op_csrrw; break;
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+ }
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+ break;
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case 2: op = rv_op_csrrs; break;
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case 3: op = rv_op_csrrc; break;
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case 4: