target/riscv: Add zcmop extension

Zcmop defines eight 16-bit MOP instructions named C.MOP.n, where n is
an odd integer between 1 and 15, inclusive. C.MOP.n is encoded in
the reserved encoding space corresponding to C.LUI xn, 0.

Unlike the MOPs defined in the Zimop extension, the C.MOP.n instructions
are defined to not write any register.

In current implementation, C.MOP.n only has an check function, without any
other more behavior.

Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Deepak Gupta <debug@rivosinc.com>
Message-ID: <20240709113652.1239-4-zhiwei_liu@linux.alibaba.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

6 files changed, 39 insertions, 0 deletions

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index ac50382..f4f8287 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -131,6 +131,7 @@ const RISCVIsaExtData isa_edata_arr[] = {
     ISA_EXT_DATA_ENTRY(zcf, PRIV_VERSION_1_12_0, ext_zcf),
     ISA_EXT_DATA_ENTRY(zcd, PRIV_VERSION_1_12_0, ext_zcd),
     ISA_EXT_DATA_ENTRY(zce, PRIV_VERSION_1_12_0, ext_zce),
+    ISA_EXT_DATA_ENTRY(zcmop, PRIV_VERSION_1_13_0, ext_zcmop),
     ISA_EXT_DATA_ENTRY(zcmp, PRIV_VERSION_1_12_0, ext_zcmp),
     ISA_EXT_DATA_ENTRY(zcmt, PRIV_VERSION_1_12_0, ext_zcmt),
     ISA_EXT_DATA_ENTRY(zba, PRIV_VERSION_1_12_0, ext_zba),
@@ -1473,6 +1474,7 @@ const RISCVCPUMultiExtConfig riscv_cpu_extensions[] = {
     MULTI_EXT_CFG_BOOL("zihintntl", ext_zihintntl, true),
     MULTI_EXT_CFG_BOOL("zihintpause", ext_zihintpause, true),
     MULTI_EXT_CFG_BOOL("zimop", ext_zimop, false),
+    MULTI_EXT_CFG_BOOL("zcmop", ext_zcmop, false),
     MULTI_EXT_CFG_BOOL("zacas", ext_zacas, false),
     MULTI_EXT_CFG_BOOL("zaamo", ext_zaamo, false),
     MULTI_EXT_CFG_BOOL("zalrsc", ext_zalrsc, false),
diff --git a/target/riscv/cpu_cfg.h b/target/riscv/cpu_cfg.h
index 9f53512..d85e54b 100644
--- a/target/riscv/cpu_cfg.h
+++ b/target/riscv/cpu_cfg.h
@@ -72,6 +72,7 @@ struct RISCVCPUConfig {
     bool ext_zihintpause;
     bool ext_zihpm;
     bool ext_zimop;
+    bool ext_zcmop;
     bool ext_ztso;
     bool ext_smstateen;
     bool ext_sstc;
diff --git a/target/riscv/insn16.decode b/target/riscv/insn16.decode
index b96c534..3953bcf 100644
--- a/target/riscv/insn16.decode
+++ b/target/riscv/insn16.decode
@@ -140,6 +140,7 @@ sw                110  ... ... .. ... 00 @cs_w
 addi              000 .  .....  ..... 01 @ci
 addi              010 .  .....  ..... 01 @c_li
 {
+  c_mop_n         011 0 0 n:3 1 00000 01
   illegal         011 0  -----  00000 01 # c.addi16sp and c.lui, RES nzimm=0
   addi            011 .  00010  ..... 01 @c_addi16sp
   lui             011 .  .....  ..... 01 @c_lui
diff --git a/target/riscv/insn_trans/trans_rvzcmop.c.inc b/target/riscv/insn_trans/trans_rvzcmop.c.inc
new file mode 100644
index 0000000..7205586
--- /dev/null
+++ b/target/riscv/insn_trans/trans_rvzcmop.c.inc
@@ -0,0 +1,29 @@
+/*
+ * RISC-V translation routines for compressed May-Be-Operation(zcmop).
+ *
+ * Copyright (c) 2024 Alibaba Group.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2 or later, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define REQUIRE_ZCMOP(ctx) do {           \
+    if (!ctx->cfg_ptr->ext_zcmop) {       \
+        return false;                     \
+    }                                     \
+} while (0)
+
+static bool trans_c_mop_n(DisasContext *ctx, arg_c_mop_n *a)
+{
+    REQUIRE_ZCMOP(ctx);
+    return true;
+}
diff --git a/target/riscv/tcg/tcg-cpu.c b/target/riscv/tcg/tcg-cpu.c
index ecf366d..b8814ab 100644
--- a/target/riscv/tcg/tcg-cpu.c
+++ b/target/riscv/tcg/tcg-cpu.c
@@ -549,6 +549,11 @@ void riscv_cpu_validate_set_extensions(RISCVCPU *cpu, Error **errp)
         }
     }
 
+    if (cpu->cfg.ext_zcmop && !cpu->cfg.ext_zca) {
+        error_setg(errp, "Zcmop extensions require Zca");
+        return;
+    }
+
     if (mcc->misa_mxl_max != MXL_RV32 && cpu->cfg.ext_zcf) {
         error_setg(errp, "Zcf extension is only relevant to RV32");
         return;
diff --git a/target/riscv/translate.c b/target/riscv/translate.c
index 379b682..8a546f4 100644
--- a/target/riscv/translate.c
+++ b/target/riscv/translate.c
@@ -1114,6 +1114,7 @@ static uint32_t opcode_at(DisasContextBase *dcbase, target_ulong pc)
 /* Include the auto-generated decoder for 16 bit insn */
 #include "decode-insn16.c.inc"
 #include "insn_trans/trans_rvzce.c.inc"
+#include "insn_trans/trans_rvzcmop.c.inc"
 
 /* Include decoders for factored-out extensions */
 #include "decode-XVentanaCondOps.c.inc"