[PATCH 0/2] Add support for (ratified) Zacas extension

[PATCH 0/2] Add support for (ratified) Zacas extension

[Rob Bradford]

The Zacas extension is now ratified:
https://github.com/riscv/riscv-zacas

This series uses a patch from Weiwei Li from:
https://github.com/plctlab/plct-qemu/tree/plct-zacas-dev with the
following changes:

* Fixed destination register (looks like a copy and paste error),
* Fixed extension name enabling,
* Minor coding style fixes,
* Updated for new extension handling & cpu.h header split.

This patch was mentioned on the list here:
https://www.mail-archive.com/qemu-devel@nongnu.org/msg970280.html

The series was tested against riscv-tests from the following PR:
https://github.com/riscv-software-src/riscv-tests/pull/492

Rob Bradford (1):
  disas/riscv: Add amocas.[w,d,q] instructions

Weiwei Li (1):
  target/riscv: Add support for Zacas extension

 disas/riscv.c                               |   9 ++
 target/riscv/cpu.c                          |   2 +
 target/riscv/cpu_cfg.h                      |   1 +
 target/riscv/insn32.decode                  |   6 +
 target/riscv/insn_trans/trans_rvzacas.c.inc | 150 ++++++++++++++++++++
 target/riscv/tcg/tcg-cpu.c                  |   5 +
 target/riscv/translate.c                    |   1 +
 7 files changed, 174 insertions(+)
 create mode 100644 target/riscv/insn_trans/trans_rvzacas.c.inc

-- 
2.43.0

[PATCH 1/2] target/riscv: Add support for Zacas extension

[Rob Bradford]

From: Weiwei Li <liweiwei@iscas.ac.cn>

Add support for amocas.w/d/q instructions which are part of the ratified
Zacas extension: https://github.com/riscv/riscv-zacas

Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
---
 target/riscv/cpu.c                          |   2 +
 target/riscv/cpu_cfg.h                      |   1 +
 target/riscv/insn32.decode                  |   6 +
 target/riscv/insn_trans/trans_rvzacas.c.inc | 150 ++++++++++++++++++++
 target/riscv/tcg/tcg-cpu.c                  |   5 +
 target/riscv/translate.c                    |   1 +
 6 files changed, 165 insertions(+)
 create mode 100644 target/riscv/insn_trans/trans_rvzacas.c.inc

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index 83c7c0cf07..a265833b17 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -87,6 +87,7 @@ const RISCVIsaExtData isa_edata_arr[] = {
     ISA_EXT_DATA_ENTRY(zihintpause, PRIV_VERSION_1_10_0, ext_zihintpause),
     ISA_EXT_DATA_ENTRY(zihpm, PRIV_VERSION_1_12_0, ext_zihpm),
     ISA_EXT_DATA_ENTRY(zmmul, PRIV_VERSION_1_12_0, ext_zmmul),
+    ISA_EXT_DATA_ENTRY(zacas, PRIV_VERSION_1_12_0, ext_zacas),
     ISA_EXT_DATA_ENTRY(zawrs, PRIV_VERSION_1_12_0, ext_zawrs),
     ISA_EXT_DATA_ENTRY(zfa, PRIV_VERSION_1_12_0, ext_zfa),
     ISA_EXT_DATA_ENTRY(zfbfmin, PRIV_VERSION_1_12_0, ext_zfbfmin),
@@ -1300,6 +1301,7 @@ const RISCVCPUMultiExtConfig riscv_cpu_extensions[] = {
     MULTI_EXT_CFG_BOOL("zicsr", ext_zicsr, true),
     MULTI_EXT_CFG_BOOL("zihintntl", ext_zihintntl, true),
     MULTI_EXT_CFG_BOOL("zihintpause", ext_zihintpause, true),
+    MULTI_EXT_CFG_BOOL("zacas", ext_zacas, false),
     MULTI_EXT_CFG_BOOL("zawrs", ext_zawrs, true),
     MULTI_EXT_CFG_BOOL("zfa", ext_zfa, true),
     MULTI_EXT_CFG_BOOL("zfh", ext_zfh, false),
diff --git a/target/riscv/cpu_cfg.h b/target/riscv/cpu_cfg.h
index f4605fb190..d516de4a44 100644
--- a/target/riscv/cpu_cfg.h
+++ b/target/riscv/cpu_cfg.h
@@ -77,6 +77,7 @@ struct RISCVCPUConfig {
     bool ext_svnapot;
     bool ext_svpbmt;
     bool ext_zdinx;
+    bool ext_zacas;
     bool ext_zawrs;
     bool ext_zfa;
     bool ext_zfbfmin;
diff --git a/target/riscv/insn32.decode b/target/riscv/insn32.decode
index 33597fe2bb..f22df04cfd 100644
--- a/target/riscv/insn32.decode
+++ b/target/riscv/insn32.decode
@@ -1004,3 +1004,9 @@ vgmul_vv    101000 1 ..... 10001 010 ..... 1110111 @r2_vm_1
 vsm4k_vi    100001 1 ..... ..... 010 ..... 1110111 @r_vm_1
 vsm4r_vv    101000 1 ..... 10000 010 ..... 1110111 @r2_vm_1
 vsm4r_vs    101001 1 ..... 10000 010 ..... 1110111 @r2_vm_1
+
+# *** RV32 Zacas Standard Extension ***
+amocas_w    00101 . . ..... ..... 010 ..... 0101111 @atom_st
+amocas_d    00101 . . ..... ..... 011 ..... 0101111 @atom_st
+# *** RV64 Zacas Standard Extension ***
+amocas_q    00101 . . ..... ..... 100 ..... 0101111 @atom_st
diff --git a/target/riscv/insn_trans/trans_rvzacas.c.inc b/target/riscv/insn_trans/trans_rvzacas.c.inc
new file mode 100644
index 0000000000..5d274d4c08
--- /dev/null
+++ b/target/riscv/insn_trans/trans_rvzacas.c.inc
@@ -0,0 +1,150 @@
+/*
+ * RISC-V translation routines for the RV64 Zacas Standard Extension.
+ *
+ * Copyright (c) 2020-2023 PLCT Lab
+ *
+ * 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_ZACAS(ctx) do {          \
+    if (!ctx->cfg_ptr->ext_zacas) {      \
+        return false;                     \
+    }                                     \
+} while (0)
+
+static bool gen_cmpxchg(DisasContext *ctx, arg_atomic *a, MemOp mop)
+{
+    TCGv dest = get_gpr(ctx, a->rd, EXT_NONE);
+    TCGv src1 = get_address(ctx, a->rs1, 0);
+    TCGv src2 = get_gpr(ctx, a->rs2, EXT_NONE);
+
+    decode_save_opc(ctx);
+    tcg_gen_atomic_cmpxchg_tl(dest, src1, dest, src2, ctx->mem_idx, mop);
+
+    gen_set_gpr(ctx, a->rd, dest);
+    return true;
+}
+
+static bool trans_amocas_w(DisasContext *ctx, arg_amocas_w *a)
+{
+    REQUIRE_ZACAS(ctx);
+    return gen_cmpxchg(ctx, a, MO_ALIGN | MO_TESL);
+}
+
+static TCGv_i64 get_gpr_pair(DisasContext *ctx, int reg_num)
+{
+    TCGv_i64 t;
+
+    assert(get_ol(ctx) == MXL_RV32);
+
+    if (reg_num == 0) {
+        return tcg_constant_i64(0);
+    }
+
+    t = tcg_temp_new_i64();
+    tcg_gen_concat_tl_i64(t, cpu_gpr[reg_num], cpu_gpr[reg_num + 1]);
+    return t;
+}
+
+static void gen_set_gpr_pair(DisasContext *ctx, int reg_num, TCGv_i64 t)
+{
+    assert(get_ol(ctx) == MXL_RV32);
+
+    if (reg_num != 0) {
+#ifdef TARGET_RISCV32
+        tcg_gen_extr_i64_i32(cpu_gpr[reg_num], cpu_gpr[reg_num + 1], t);
+#else
+        tcg_gen_ext32s_i64(cpu_gpr[reg_num], t);
+        tcg_gen_sari_i64(cpu_gpr[reg_num + 1], t, 32);
+#endif
+
+        if (get_xl_max(ctx) == MXL_RV128) {
+            tcg_gen_sari_tl(cpu_gprh[reg_num], cpu_gpr[reg_num], 63);
+            tcg_gen_sari_tl(cpu_gprh[reg_num + 1], cpu_gpr[reg_num + 1], 63);
+        }
+    }
+}
+
+static bool gen_cmpxchg64(DisasContext *ctx, arg_atomic *a, MemOp mop)
+{
+    /*
+     * Encodings with odd numbered registers specified in rs2 and rd are
+     * reserved.
+     */
+    if ((a->rs2 | a->rd) & 1) {
+        return false;
+    }
+
+    TCGv_i64 dest = get_gpr_pair(ctx, a->rd);
+    TCGv src1 = get_address(ctx, a->rs1, 0);
+    TCGv_i64 src2 = get_gpr_pair(ctx, a->rs2);
+
+    decode_save_opc(ctx);
+    tcg_gen_atomic_cmpxchg_i64(dest, src1, dest, src2, ctx->mem_idx, mop);
+
+    gen_set_gpr_pair(ctx, a->rd, dest);
+    return true;
+}
+
+static bool trans_amocas_d(DisasContext *ctx, arg_amocas_d *a)
+{
+    REQUIRE_ZACAS(ctx);
+    switch (get_ol(ctx)) {
+    case MXL_RV32:
+        return gen_cmpxchg64(ctx, a, MO_ALIGN | MO_TEUQ);
+    case MXL_RV64:
+    case MXL_RV128:
+        return gen_cmpxchg(ctx, a, MO_ALIGN | MO_TEUQ);
+    default:
+        g_assert_not_reached();
+    }
+}
+
+static bool trans_amocas_q(DisasContext *ctx, arg_amocas_q *a)
+{
+    REQUIRE_ZACAS(ctx);
+    REQUIRE_64BIT(ctx);
+
+    /*
+     * Encodings with odd numbered registers specified in rs2 and rd are
+     * reserved.
+     */
+    if ((a->rs2 | a->rd) & 1) {
+        return false;
+    }
+
+#ifdef TARGET_RISCV64
+    TCGv_i128 dest = tcg_temp_new_i128();
+    TCGv src1 = get_address(ctx, a->rs1, 0);
+    TCGv_i128 src2 = tcg_temp_new_i128();
+    TCGv_i64 src2l = get_gpr(ctx, a->rs2, EXT_NONE);
+    TCGv_i64 src2h = get_gpr(ctx, a->rs2 == 0 ? 0 : a->rs2 + 1, EXT_NONE);
+    TCGv_i64 destl = get_gpr(ctx, a->rd, EXT_NONE);
+    TCGv_i64 desth = get_gpr(ctx, a->rd == 0 ? 0 : a->rd + 1, EXT_NONE);
+
+    tcg_gen_concat_i64_i128(src2, src2l, src2h);
+    tcg_gen_concat_i64_i128(dest, destl, desth);
+    decode_save_opc(ctx);
+    tcg_gen_atomic_cmpxchg_i128(dest, src1, dest, src2, ctx->mem_idx,
+                                (MO_ALIGN | MO_TEUO));
+
+    tcg_gen_extr_i128_i64(destl, desth, dest);
+
+    if (a->rd != 0) {
+        gen_set_gpr(ctx, a->rd, destl);
+        gen_set_gpr(ctx, a->rd + 1, desth);
+    }
+#endif
+
+    return true;
+}
diff --git a/target/riscv/tcg/tcg-cpu.c b/target/riscv/tcg/tcg-cpu.c
index 8a35683a34..29b5a88931 100644
--- a/target/riscv/tcg/tcg-cpu.c
+++ b/target/riscv/tcg/tcg-cpu.c
@@ -343,6 +343,11 @@ void riscv_cpu_validate_set_extensions(RISCVCPU *cpu, Error **errp)
         return;
     }
 
+    if ((cpu->cfg.ext_zacas) && !riscv_has_ext(env, RVA)) {
+        error_setg(errp, "Zacas extension requires A extension");
+        return;
+    }
+
     if ((cpu->cfg.ext_zawrs) && !riscv_has_ext(env, RVA)) {
         error_setg(errp, "Zawrs extension requires A extension");
         return;
diff --git a/target/riscv/translate.c b/target/riscv/translate.c
index f0be79bb16..071fbad7ef 100644
--- a/target/riscv/translate.c
+++ b/target/riscv/translate.c
@@ -1089,6 +1089,7 @@ static uint32_t opcode_at(DisasContextBase *dcbase, target_ulong pc)
 #include "insn_trans/trans_rvv.c.inc"
 #include "insn_trans/trans_rvb.c.inc"
 #include "insn_trans/trans_rvzicond.c.inc"
+#include "insn_trans/trans_rvzacas.c.inc"
 #include "insn_trans/trans_rvzawrs.c.inc"
 #include "insn_trans/trans_rvzicbo.c.inc"
 #include "insn_trans/trans_rvzfa.c.inc"
-- 
2.43.0

[PATCH 2/2] disas/riscv: Add amocas.[w,d,q] instructions

[Rob Bradford]

Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
---
 disas/riscv.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/disas/riscv.c b/disas/riscv.c
index e9458e574b..8a546d5ea5 100644
--- a/disas/riscv.c
+++ b/disas/riscv.c
@@ -903,6 +903,9 @@ typedef enum {
     rv_op_vwsll_vv = 872,
     rv_op_vwsll_vx = 873,
     rv_op_vwsll_vi = 874,
+    rv_op_amocas_w = 875,
+    rv_op_amocas_d = 876,
+    rv_op_amocas_q = 877,
 } rv_op;
 
 /* register names */
@@ -2090,6 +2093,9 @@ const rv_opcode_data rvi_opcode_data[] = {
     { "vwsll.vv", rv_codec_v_r, rv_fmt_vd_vs2_vs1_vm, NULL, 0, 0, 0 },
     { "vwsll.vx", rv_codec_v_r, rv_fmt_vd_vs2_rs1_vm, NULL, 0, 0, 0 },
     { "vwsll.vi", rv_codec_v_i, rv_fmt_vd_vs2_uimm_vm, NULL, 0, 0, 0 },
+    { "amocas.w", rv_codec_r_a, rv_fmt_aqrl_rd_rs2_rs1, NULL, 0, 0, 0 },
+    { "amocas.d", rv_codec_r_a, rv_fmt_aqrl_rd_rs2_rs1, NULL, 0, 0, 0 },
+    { "amocas.q", rv_codec_r_a, rv_fmt_aqrl_rd_rs2_rs1, NULL, 0, 0, 0 },
 };
 
 /* CSR names */
@@ -2841,6 +2847,9 @@ static void decode_inst_opcode(rv_decode *dec, rv_isa isa)
             case 34: op = rv_op_amoxor_w; break;
             case 35: op = rv_op_amoxor_d; break;
             case 36: op = rv_op_amoxor_q; break;
+            case 42: op = rv_op_amocas_w; break;
+            case 43: op = rv_op_amocas_d; break;
+            case 44: op = rv_op_amocas_q; break;
             case 66: op = rv_op_amoor_w; break;
             case 67: op = rv_op_amoor_d; break;
             case 68: op = rv_op_amoor_q; break;
-- 
2.43.0

Re: [PATCH 1/2] target/riscv: Add support for Zacas extension

[Daniel Henrique Barboza]

On 12/7/23 12:32, Rob Bradford wrote:
> From: Weiwei Li <liweiwei@iscas.ac.cn>
> 
> Add support for amocas.w/d/q instructions which are part of the ratified
> Zacas extension: https://github.com/riscv/riscv-zacas
> 
> Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
> Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
> Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
> ---

Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>

>   target/riscv/cpu.c                          |   2 +
>   target/riscv/cpu_cfg.h                      |   1 +
>   target/riscv/insn32.decode                  |   6 +
>   target/riscv/insn_trans/trans_rvzacas.c.inc | 150 ++++++++++++++++++++
>   target/riscv/tcg/tcg-cpu.c                  |   5 +
>   target/riscv/translate.c                    |   1 +
>   6 files changed, 165 insertions(+)
>   create mode 100644 target/riscv/insn_trans/trans_rvzacas.c.inc
> 
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index 83c7c0cf07..a265833b17 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -87,6 +87,7 @@ const RISCVIsaExtData isa_edata_arr[] = {
>       ISA_EXT_DATA_ENTRY(zihintpause, PRIV_VERSION_1_10_0, ext_zihintpause),
>       ISA_EXT_DATA_ENTRY(zihpm, PRIV_VERSION_1_12_0, ext_zihpm),
>       ISA_EXT_DATA_ENTRY(zmmul, PRIV_VERSION_1_12_0, ext_zmmul),
> +    ISA_EXT_DATA_ENTRY(zacas, PRIV_VERSION_1_12_0, ext_zacas),
>       ISA_EXT_DATA_ENTRY(zawrs, PRIV_VERSION_1_12_0, ext_zawrs),
>       ISA_EXT_DATA_ENTRY(zfa, PRIV_VERSION_1_12_0, ext_zfa),
>       ISA_EXT_DATA_ENTRY(zfbfmin, PRIV_VERSION_1_12_0, ext_zfbfmin),
> @@ -1300,6 +1301,7 @@ const RISCVCPUMultiExtConfig riscv_cpu_extensions[] = {
>       MULTI_EXT_CFG_BOOL("zicsr", ext_zicsr, true),
>       MULTI_EXT_CFG_BOOL("zihintntl", ext_zihintntl, true),
>       MULTI_EXT_CFG_BOOL("zihintpause", ext_zihintpause, true),
> +    MULTI_EXT_CFG_BOOL("zacas", ext_zacas, false),
>       MULTI_EXT_CFG_BOOL("zawrs", ext_zawrs, true),
>       MULTI_EXT_CFG_BOOL("zfa", ext_zfa, true),
>       MULTI_EXT_CFG_BOOL("zfh", ext_zfh, false),
> diff --git a/target/riscv/cpu_cfg.h b/target/riscv/cpu_cfg.h
> index f4605fb190..d516de4a44 100644
> --- a/target/riscv/cpu_cfg.h
> +++ b/target/riscv/cpu_cfg.h
> @@ -77,6 +77,7 @@ struct RISCVCPUConfig {
>       bool ext_svnapot;
>       bool ext_svpbmt;
>       bool ext_zdinx;
> +    bool ext_zacas;
>       bool ext_zawrs;
>       bool ext_zfa;
>       bool ext_zfbfmin;
> diff --git a/target/riscv/insn32.decode b/target/riscv/insn32.decode
> index 33597fe2bb..f22df04cfd 100644
> --- a/target/riscv/insn32.decode
> +++ b/target/riscv/insn32.decode
> @@ -1004,3 +1004,9 @@ vgmul_vv    101000 1 ..... 10001 010 ..... 1110111 @r2_vm_1
>   vsm4k_vi    100001 1 ..... ..... 010 ..... 1110111 @r_vm_1
>   vsm4r_vv    101000 1 ..... 10000 010 ..... 1110111 @r2_vm_1
>   vsm4r_vs    101001 1 ..... 10000 010 ..... 1110111 @r2_vm_1
> +
> +# *** RV32 Zacas Standard Extension ***
> +amocas_w    00101 . . ..... ..... 010 ..... 0101111 @atom_st
> +amocas_d    00101 . . ..... ..... 011 ..... 0101111 @atom_st
> +# *** RV64 Zacas Standard Extension ***
> +amocas_q    00101 . . ..... ..... 100 ..... 0101111 @atom_st
> diff --git a/target/riscv/insn_trans/trans_rvzacas.c.inc b/target/riscv/insn_trans/trans_rvzacas.c.inc
> new file mode 100644
> index 0000000000..5d274d4c08
> --- /dev/null
> +++ b/target/riscv/insn_trans/trans_rvzacas.c.inc
> @@ -0,0 +1,150 @@
> +/*
> + * RISC-V translation routines for the RV64 Zacas Standard Extension.
> + *
> + * Copyright (c) 2020-2023 PLCT Lab
> + *
> + * 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_ZACAS(ctx) do {          \
> +    if (!ctx->cfg_ptr->ext_zacas) {      \
> +        return false;                     \
> +    }                                     \
> +} while (0)
> +
> +static bool gen_cmpxchg(DisasContext *ctx, arg_atomic *a, MemOp mop)
> +{
> +    TCGv dest = get_gpr(ctx, a->rd, EXT_NONE);
> +    TCGv src1 = get_address(ctx, a->rs1, 0);
> +    TCGv src2 = get_gpr(ctx, a->rs2, EXT_NONE);
> +
> +    decode_save_opc(ctx);
> +    tcg_gen_atomic_cmpxchg_tl(dest, src1, dest, src2, ctx->mem_idx, mop);
> +
> +    gen_set_gpr(ctx, a->rd, dest);
> +    return true;
> +}
> +
> +static bool trans_amocas_w(DisasContext *ctx, arg_amocas_w *a)
> +{
> +    REQUIRE_ZACAS(ctx);
> +    return gen_cmpxchg(ctx, a, MO_ALIGN | MO_TESL);
> +}
> +
> +static TCGv_i64 get_gpr_pair(DisasContext *ctx, int reg_num)
> +{
> +    TCGv_i64 t;
> +
> +    assert(get_ol(ctx) == MXL_RV32);
> +
> +    if (reg_num == 0) {
> +        return tcg_constant_i64(0);
> +    }
> +
> +    t = tcg_temp_new_i64();
> +    tcg_gen_concat_tl_i64(t, cpu_gpr[reg_num], cpu_gpr[reg_num + 1]);
> +    return t;
> +}
> +
> +static void gen_set_gpr_pair(DisasContext *ctx, int reg_num, TCGv_i64 t)
> +{
> +    assert(get_ol(ctx) == MXL_RV32);
> +
> +    if (reg_num != 0) {
> +#ifdef TARGET_RISCV32
> +        tcg_gen_extr_i64_i32(cpu_gpr[reg_num], cpu_gpr[reg_num + 1], t);
> +#else
> +        tcg_gen_ext32s_i64(cpu_gpr[reg_num], t);
> +        tcg_gen_sari_i64(cpu_gpr[reg_num + 1], t, 32);
> +#endif
> +
> +        if (get_xl_max(ctx) == MXL_RV128) {
> +            tcg_gen_sari_tl(cpu_gprh[reg_num], cpu_gpr[reg_num], 63);
> +            tcg_gen_sari_tl(cpu_gprh[reg_num + 1], cpu_gpr[reg_num + 1], 63);
> +        }
> +    }
> +}
> +
> +static bool gen_cmpxchg64(DisasContext *ctx, arg_atomic *a, MemOp mop)
> +{
> +    /*
> +     * Encodings with odd numbered registers specified in rs2 and rd are
> +     * reserved.
> +     */
> +    if ((a->rs2 | a->rd) & 1) {
> +        return false;
> +    }
> +
> +    TCGv_i64 dest = get_gpr_pair(ctx, a->rd);
> +    TCGv src1 = get_address(ctx, a->rs1, 0);
> +    TCGv_i64 src2 = get_gpr_pair(ctx, a->rs2);
> +
> +    decode_save_opc(ctx);
> +    tcg_gen_atomic_cmpxchg_i64(dest, src1, dest, src2, ctx->mem_idx, mop);
> +
> +    gen_set_gpr_pair(ctx, a->rd, dest);
> +    return true;
> +}
> +
> +static bool trans_amocas_d(DisasContext *ctx, arg_amocas_d *a)
> +{
> +    REQUIRE_ZACAS(ctx);
> +    switch (get_ol(ctx)) {
> +    case MXL_RV32:
> +        return gen_cmpxchg64(ctx, a, MO_ALIGN | MO_TEUQ);
> +    case MXL_RV64:
> +    case MXL_RV128:
> +        return gen_cmpxchg(ctx, a, MO_ALIGN | MO_TEUQ);
> +    default:
> +        g_assert_not_reached();
> +    }
> +}
> +
> +static bool trans_amocas_q(DisasContext *ctx, arg_amocas_q *a)
> +{
> +    REQUIRE_ZACAS(ctx);
> +    REQUIRE_64BIT(ctx);
> +
> +    /*
> +     * Encodings with odd numbered registers specified in rs2 and rd are
> +     * reserved.
> +     */
> +    if ((a->rs2 | a->rd) & 1) {
> +        return false;
> +    }
> +
> +#ifdef TARGET_RISCV64
> +    TCGv_i128 dest = tcg_temp_new_i128();
> +    TCGv src1 = get_address(ctx, a->rs1, 0);
> +    TCGv_i128 src2 = tcg_temp_new_i128();
> +    TCGv_i64 src2l = get_gpr(ctx, a->rs2, EXT_NONE);
> +    TCGv_i64 src2h = get_gpr(ctx, a->rs2 == 0 ? 0 : a->rs2 + 1, EXT_NONE);
> +    TCGv_i64 destl = get_gpr(ctx, a->rd, EXT_NONE);
> +    TCGv_i64 desth = get_gpr(ctx, a->rd == 0 ? 0 : a->rd + 1, EXT_NONE);
> +
> +    tcg_gen_concat_i64_i128(src2, src2l, src2h);
> +    tcg_gen_concat_i64_i128(dest, destl, desth);
> +    decode_save_opc(ctx);
> +    tcg_gen_atomic_cmpxchg_i128(dest, src1, dest, src2, ctx->mem_idx,
> +                                (MO_ALIGN | MO_TEUO));
> +
> +    tcg_gen_extr_i128_i64(destl, desth, dest);
> +
> +    if (a->rd != 0) {
> +        gen_set_gpr(ctx, a->rd, destl);
> +        gen_set_gpr(ctx, a->rd + 1, desth);
> +    }
> +#endif
> +
> +    return true;
> +}
> diff --git a/target/riscv/tcg/tcg-cpu.c b/target/riscv/tcg/tcg-cpu.c
> index 8a35683a34..29b5a88931 100644
> --- a/target/riscv/tcg/tcg-cpu.c
> +++ b/target/riscv/tcg/tcg-cpu.c
> @@ -343,6 +343,11 @@ void riscv_cpu_validate_set_extensions(RISCVCPU *cpu, Error **errp)
>           return;
>       }
>   
> +    if ((cpu->cfg.ext_zacas) && !riscv_has_ext(env, RVA)) {
> +        error_setg(errp, "Zacas extension requires A extension");
> +        return;
> +    }
> +
>       if ((cpu->cfg.ext_zawrs) && !riscv_has_ext(env, RVA)) {
>           error_setg(errp, "Zawrs extension requires A extension");
>           return;
> diff --git a/target/riscv/translate.c b/target/riscv/translate.c
> index f0be79bb16..071fbad7ef 100644
> --- a/target/riscv/translate.c
> +++ b/target/riscv/translate.c
> @@ -1089,6 +1089,7 @@ static uint32_t opcode_at(DisasContextBase *dcbase, target_ulong pc)
>   #include "insn_trans/trans_rvv.c.inc"
>   #include "insn_trans/trans_rvb.c.inc"
>   #include "insn_trans/trans_rvzicond.c.inc"
> +#include "insn_trans/trans_rvzacas.c.inc"
>   #include "insn_trans/trans_rvzawrs.c.inc"
>   #include "insn_trans/trans_rvzicbo.c.inc"
>   #include "insn_trans/trans_rvzfa.c.inc"

Re: [PATCH 2/2] disas/riscv: Add amocas.[w,d,q] instructions

[Daniel Henrique Barboza]

On 12/7/23 12:32, Rob Bradford wrote:
> Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
> ---
>   disas/riscv.c | 9 +++++++++
>   1 file changed, 9 insertions(+)
> 
> diff --git a/disas/riscv.c b/disas/riscv.c
> index e9458e574b..8a546d5ea5 100644
> --- a/disas/riscv.c
> +++ b/disas/riscv.c
> @@ -903,6 +903,9 @@ typedef enum {
>       rv_op_vwsll_vv = 872,
>       rv_op_vwsll_vx = 873,
>       rv_op_vwsll_vi = 874,
> +    rv_op_amocas_w = 875,
> +    rv_op_amocas_d = 876,
> +    rv_op_amocas_q = 877,
>   } rv_op;
>   
>   /* register names */
> @@ -2090,6 +2093,9 @@ const rv_opcode_data rvi_opcode_data[] = {
>       { "vwsll.vv", rv_codec_v_r, rv_fmt_vd_vs2_vs1_vm, NULL, 0, 0, 0 },
>       { "vwsll.vx", rv_codec_v_r, rv_fmt_vd_vs2_rs1_vm, NULL, 0, 0, 0 },
>       { "vwsll.vi", rv_codec_v_i, rv_fmt_vd_vs2_uimm_vm, NULL, 0, 0, 0 },
> +    { "amocas.w", rv_codec_r_a, rv_fmt_aqrl_rd_rs2_rs1, NULL, 0, 0, 0 },
> +    { "amocas.d", rv_codec_r_a, rv_fmt_aqrl_rd_rs2_rs1, NULL, 0, 0, 0 },
> +    { "amocas.q", rv_codec_r_a, rv_fmt_aqrl_rd_rs2_rs1, NULL, 0, 0, 0 },
>   };
>   
>   /* CSR names */
> @@ -2841,6 +2847,9 @@ static void decode_inst_opcode(rv_decode *dec, rv_isa isa)
>               case 34: op = rv_op_amoxor_w; break;
>               case 35: op = rv_op_amoxor_d; break;
>               case 36: op = rv_op_amoxor_q; break;
> +            case 42: op = rv_op_amocas_w; break;
> +            case 43: op = rv_op_amocas_d; break;
> +            case 44: op = rv_op_amocas_q; break;

scripts/checkpatch.pl will complain about this change:

2/2 Checking commit 9bddd6d4337d (disas/riscv: Add amocas.[w,d,q] instructions)
ERROR: trailing statements should be on next line
#40: FILE: disas/riscv.c:2850:
+            case 42: op = rv_op_amocas_w; break;

ERROR: trailing statements should be on next line
#41: FILE: disas/riscv.c:2851:
+            case 43: op = rv_op_amocas_d; break;

ERROR: trailing statements should be on next line
#42: FILE: disas/riscv.c:2852:
+            case 44: op = rv_op_amocas_q; break;

total: 3 errors, 0 warnings, 27 lines checked


This is an existing style problem thus I'm ignoring it. We can drop a separated patch
to fix the coding style.

Patch LGTM.


Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>



>               case 66: op = rv_op_amoor_w; break;
>               case 67: op = rv_op_amoor_d; break;
>               case 68: op = rv_op_amoor_q; break;

Re: [PATCH 1/2] target/riscv: Add support for Zacas extension

[Alistair Francis]

On Fri, Dec 8, 2023 at 1:40 AM Rob Bradford <rbradford@rivosinc.com> wrote:
>
> From: Weiwei Li <liweiwei@iscas.ac.cn>
>
> Add support for amocas.w/d/q instructions which are part of the ratified
> Zacas extension: https://github.com/riscv/riscv-zacas
>
> Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
> Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
> Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
> ---
>  target/riscv/cpu.c                          |   2 +
>  target/riscv/cpu_cfg.h                      |   1 +
>  target/riscv/insn32.decode                  |   6 +
>  target/riscv/insn_trans/trans_rvzacas.c.inc | 150 ++++++++++++++++++++
>  target/riscv/tcg/tcg-cpu.c                  |   5 +
>  target/riscv/translate.c                    |   1 +
>  6 files changed, 165 insertions(+)
>  create mode 100644 target/riscv/insn_trans/trans_rvzacas.c.inc
>
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index 83c7c0cf07..a265833b17 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -87,6 +87,7 @@ const RISCVIsaExtData isa_edata_arr[] = {
>      ISA_EXT_DATA_ENTRY(zihintpause, PRIV_VERSION_1_10_0, ext_zihintpause),
>      ISA_EXT_DATA_ENTRY(zihpm, PRIV_VERSION_1_12_0, ext_zihpm),
>      ISA_EXT_DATA_ENTRY(zmmul, PRIV_VERSION_1_12_0, ext_zmmul),
> +    ISA_EXT_DATA_ENTRY(zacas, PRIV_VERSION_1_12_0, ext_zacas),
>      ISA_EXT_DATA_ENTRY(zawrs, PRIV_VERSION_1_12_0, ext_zawrs),
>      ISA_EXT_DATA_ENTRY(zfa, PRIV_VERSION_1_12_0, ext_zfa),
>      ISA_EXT_DATA_ENTRY(zfbfmin, PRIV_VERSION_1_12_0, ext_zfbfmin),
> @@ -1300,6 +1301,7 @@ const RISCVCPUMultiExtConfig riscv_cpu_extensions[] = {
>      MULTI_EXT_CFG_BOOL("zicsr", ext_zicsr, true),
>      MULTI_EXT_CFG_BOOL("zihintntl", ext_zihintntl, true),
>      MULTI_EXT_CFG_BOOL("zihintpause", ext_zihintpause, true),
> +    MULTI_EXT_CFG_BOOL("zacas", ext_zacas, false),
>      MULTI_EXT_CFG_BOOL("zawrs", ext_zawrs, true),
>      MULTI_EXT_CFG_BOOL("zfa", ext_zfa, true),
>      MULTI_EXT_CFG_BOOL("zfh", ext_zfh, false),
> diff --git a/target/riscv/cpu_cfg.h b/target/riscv/cpu_cfg.h
> index f4605fb190..d516de4a44 100644
> --- a/target/riscv/cpu_cfg.h
> +++ b/target/riscv/cpu_cfg.h
> @@ -77,6 +77,7 @@ struct RISCVCPUConfig {
>      bool ext_svnapot;
>      bool ext_svpbmt;
>      bool ext_zdinx;
> +    bool ext_zacas;
>      bool ext_zawrs;
>      bool ext_zfa;
>      bool ext_zfbfmin;
> diff --git a/target/riscv/insn32.decode b/target/riscv/insn32.decode
> index 33597fe2bb..f22df04cfd 100644
> --- a/target/riscv/insn32.decode
> +++ b/target/riscv/insn32.decode
> @@ -1004,3 +1004,9 @@ vgmul_vv    101000 1 ..... 10001 010 ..... 1110111 @r2_vm_1
>  vsm4k_vi    100001 1 ..... ..... 010 ..... 1110111 @r_vm_1
>  vsm4r_vv    101000 1 ..... 10000 010 ..... 1110111 @r2_vm_1
>  vsm4r_vs    101001 1 ..... 10000 010 ..... 1110111 @r2_vm_1
> +
> +# *** RV32 Zacas Standard Extension ***
> +amocas_w    00101 . . ..... ..... 010 ..... 0101111 @atom_st
> +amocas_d    00101 . . ..... ..... 011 ..... 0101111 @atom_st
> +# *** RV64 Zacas Standard Extension ***
> +amocas_q    00101 . . ..... ..... 100 ..... 0101111 @atom_st
> diff --git a/target/riscv/insn_trans/trans_rvzacas.c.inc b/target/riscv/insn_trans/trans_rvzacas.c.inc
> new file mode 100644
> index 0000000000..5d274d4c08
> --- /dev/null
> +++ b/target/riscv/insn_trans/trans_rvzacas.c.inc
> @@ -0,0 +1,150 @@
> +/*
> + * RISC-V translation routines for the RV64 Zacas Standard Extension.
> + *
> + * Copyright (c) 2020-2023 PLCT Lab
> + *
> + * 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_ZACAS(ctx) do {          \
> +    if (!ctx->cfg_ptr->ext_zacas) {      \
> +        return false;                     \
> +    }                                     \
> +} while (0)
> +
> +static bool gen_cmpxchg(DisasContext *ctx, arg_atomic *a, MemOp mop)
> +{
> +    TCGv dest = get_gpr(ctx, a->rd, EXT_NONE);
> +    TCGv src1 = get_address(ctx, a->rs1, 0);
> +    TCGv src2 = get_gpr(ctx, a->rs2, EXT_NONE);
> +
> +    decode_save_opc(ctx);
> +    tcg_gen_atomic_cmpxchg_tl(dest, src1, dest, src2, ctx->mem_idx, mop);
> +
> +    gen_set_gpr(ctx, a->rd, dest);
> +    return true;
> +}
> +
> +static bool trans_amocas_w(DisasContext *ctx, arg_amocas_w *a)
> +{
> +    REQUIRE_ZACAS(ctx);
> +    return gen_cmpxchg(ctx, a, MO_ALIGN | MO_TESL);
> +}
> +
> +static TCGv_i64 get_gpr_pair(DisasContext *ctx, int reg_num)
> +{
> +    TCGv_i64 t;
> +
> +    assert(get_ol(ctx) == MXL_RV32);
> +
> +    if (reg_num == 0) {
> +        return tcg_constant_i64(0);
> +    }
> +
> +    t = tcg_temp_new_i64();
> +    tcg_gen_concat_tl_i64(t, cpu_gpr[reg_num], cpu_gpr[reg_num + 1]);
> +    return t;
> +}
> +
> +static void gen_set_gpr_pair(DisasContext *ctx, int reg_num, TCGv_i64 t)
> +{
> +    assert(get_ol(ctx) == MXL_RV32);
> +
> +    if (reg_num != 0) {
> +#ifdef TARGET_RISCV32
> +        tcg_gen_extr_i64_i32(cpu_gpr[reg_num], cpu_gpr[reg_num + 1], t);
> +#else
> +        tcg_gen_ext32s_i64(cpu_gpr[reg_num], t);
> +        tcg_gen_sari_i64(cpu_gpr[reg_num + 1], t, 32);
> +#endif

This should be dynamic based on the MXL.

> +
> +        if (get_xl_max(ctx) == MXL_RV128) {
> +            tcg_gen_sari_tl(cpu_gprh[reg_num], cpu_gpr[reg_num], 63);
> +            tcg_gen_sari_tl(cpu_gprh[reg_num + 1], cpu_gpr[reg_num + 1], 63);
> +        }
> +    }
> +}
> +
> +static bool gen_cmpxchg64(DisasContext *ctx, arg_atomic *a, MemOp mop)
> +{
> +    /*
> +     * Encodings with odd numbered registers specified in rs2 and rd are
> +     * reserved.
> +     */
> +    if ((a->rs2 | a->rd) & 1) {
> +        return false;
> +    }
> +
> +    TCGv_i64 dest = get_gpr_pair(ctx, a->rd);
> +    TCGv src1 = get_address(ctx, a->rs1, 0);
> +    TCGv_i64 src2 = get_gpr_pair(ctx, a->rs2);
> +
> +    decode_save_opc(ctx);
> +    tcg_gen_atomic_cmpxchg_i64(dest, src1, dest, src2, ctx->mem_idx, mop);
> +
> +    gen_set_gpr_pair(ctx, a->rd, dest);
> +    return true;
> +}
> +
> +static bool trans_amocas_d(DisasContext *ctx, arg_amocas_d *a)
> +{
> +    REQUIRE_ZACAS(ctx);
> +    switch (get_ol(ctx)) {
> +    case MXL_RV32:
> +        return gen_cmpxchg64(ctx, a, MO_ALIGN | MO_TEUQ);
> +    case MXL_RV64:
> +    case MXL_RV128:
> +        return gen_cmpxchg(ctx, a, MO_ALIGN | MO_TEUQ);
> +    default:
> +        g_assert_not_reached();
> +    }
> +}
> +
> +static bool trans_amocas_q(DisasContext *ctx, arg_amocas_q *a)
> +{
> +    REQUIRE_ZACAS(ctx);
> +    REQUIRE_64BIT(ctx);
> +
> +    /*
> +     * Encodings with odd numbered registers specified in rs2 and rd are
> +     * reserved.
> +     */
> +    if ((a->rs2 | a->rd) & 1) {
> +        return false;
> +    }
> +
> +#ifdef TARGET_RISCV64

We already have a REQUIRE_64BIT(ctx), do we need this as well?

Alistair

> +    TCGv_i128 dest = tcg_temp_new_i128();
> +    TCGv src1 = get_address(ctx, a->rs1, 0);
> +    TCGv_i128 src2 = tcg_temp_new_i128();
> +    TCGv_i64 src2l = get_gpr(ctx, a->rs2, EXT_NONE);
> +    TCGv_i64 src2h = get_gpr(ctx, a->rs2 == 0 ? 0 : a->rs2 + 1, EXT_NONE);
> +    TCGv_i64 destl = get_gpr(ctx, a->rd, EXT_NONE);
> +    TCGv_i64 desth = get_gpr(ctx, a->rd == 0 ? 0 : a->rd + 1, EXT_NONE);
> +
> +    tcg_gen_concat_i64_i128(src2, src2l, src2h);
> +    tcg_gen_concat_i64_i128(dest, destl, desth);
> +    decode_save_opc(ctx);
> +    tcg_gen_atomic_cmpxchg_i128(dest, src1, dest, src2, ctx->mem_idx,
> +                                (MO_ALIGN | MO_TEUO));
> +
> +    tcg_gen_extr_i128_i64(destl, desth, dest);
> +
> +    if (a->rd != 0) {
> +        gen_set_gpr(ctx, a->rd, destl);
> +        gen_set_gpr(ctx, a->rd + 1, desth);
> +    }
> +#endif
> +
> +    return true;
> +}
> diff --git a/target/riscv/tcg/tcg-cpu.c b/target/riscv/tcg/tcg-cpu.c
> index 8a35683a34..29b5a88931 100644
> --- a/target/riscv/tcg/tcg-cpu.c
> +++ b/target/riscv/tcg/tcg-cpu.c
> @@ -343,6 +343,11 @@ void riscv_cpu_validate_set_extensions(RISCVCPU *cpu, Error **errp)
>          return;
>      }
>
> +    if ((cpu->cfg.ext_zacas) && !riscv_has_ext(env, RVA)) {
> +        error_setg(errp, "Zacas extension requires A extension");
> +        return;
> +    }
> +
>      if ((cpu->cfg.ext_zawrs) && !riscv_has_ext(env, RVA)) {
>          error_setg(errp, "Zawrs extension requires A extension");
>          return;
> diff --git a/target/riscv/translate.c b/target/riscv/translate.c
> index f0be79bb16..071fbad7ef 100644
> --- a/target/riscv/translate.c
> +++ b/target/riscv/translate.c
> @@ -1089,6 +1089,7 @@ static uint32_t opcode_at(DisasContextBase *dcbase, target_ulong pc)
>  #include "insn_trans/trans_rvv.c.inc"
>  #include "insn_trans/trans_rvb.c.inc"
>  #include "insn_trans/trans_rvzicond.c.inc"
> +#include "insn_trans/trans_rvzacas.c.inc"
>  #include "insn_trans/trans_rvzawrs.c.inc"
>  #include "insn_trans/trans_rvzicbo.c.inc"
>  #include "insn_trans/trans_rvzfa.c.inc"
> --
> 2.43.0
>
>

Re: [PATCH 2/2] disas/riscv: Add amocas.[w,d,q] instructions

[Alistair Francis]

On Fri, Dec 8, 2023 at 3:07 AM Rob Bradford <rbradford@rivosinc.com> wrote:
>
> Signed-off-by: Rob Bradford <rbradford@rivosinc.com>

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Alistair

> ---
>  disas/riscv.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
>
> diff --git a/disas/riscv.c b/disas/riscv.c
> index e9458e574b..8a546d5ea5 100644
> --- a/disas/riscv.c
> +++ b/disas/riscv.c
> @@ -903,6 +903,9 @@ typedef enum {
>      rv_op_vwsll_vv = 872,
>      rv_op_vwsll_vx = 873,
>      rv_op_vwsll_vi = 874,
> +    rv_op_amocas_w = 875,
> +    rv_op_amocas_d = 876,
> +    rv_op_amocas_q = 877,
>  } rv_op;
>
>  /* register names */
> @@ -2090,6 +2093,9 @@ const rv_opcode_data rvi_opcode_data[] = {
>      { "vwsll.vv", rv_codec_v_r, rv_fmt_vd_vs2_vs1_vm, NULL, 0, 0, 0 },
>      { "vwsll.vx", rv_codec_v_r, rv_fmt_vd_vs2_rs1_vm, NULL, 0, 0, 0 },
>      { "vwsll.vi", rv_codec_v_i, rv_fmt_vd_vs2_uimm_vm, NULL, 0, 0, 0 },
> +    { "amocas.w", rv_codec_r_a, rv_fmt_aqrl_rd_rs2_rs1, NULL, 0, 0, 0 },
> +    { "amocas.d", rv_codec_r_a, rv_fmt_aqrl_rd_rs2_rs1, NULL, 0, 0, 0 },
> +    { "amocas.q", rv_codec_r_a, rv_fmt_aqrl_rd_rs2_rs1, NULL, 0, 0, 0 },
>  };
>
>  /* CSR names */
> @@ -2841,6 +2847,9 @@ static void decode_inst_opcode(rv_decode *dec, rv_isa isa)
>              case 34: op = rv_op_amoxor_w; break;
>              case 35: op = rv_op_amoxor_d; break;
>              case 36: op = rv_op_amoxor_q; break;
> +            case 42: op = rv_op_amocas_w; break;
> +            case 43: op = rv_op_amocas_d; break;
> +            case 44: op = rv_op_amocas_q; break;
>              case 66: op = rv_op_amoor_w; break;
>              case 67: op = rv_op_amoor_d; break;
>              case 68: op = rv_op_amoor_q; break;
> --
> 2.43.0
>
>

Re: [PATCH 1/2] target/riscv: Add support for Zacas extension

[Rob Bradford]

Hi Alistair,

Thanks for providing some feedback - responses below:

On Mon, 2023-12-18 at 12:54 +1000, Alistair Francis wrote:
> On Fri, Dec 8, 2023 at 1:40 AM Rob Bradford <rbradford@rivosinc.com>
> wrote:
> > 
> > From: Weiwei Li <liweiwei@iscas.ac.cn>
> > 
> > Add support for amocas.w/d/q instructions which are part of the
> > ratified
> > Zacas extension: https://github.com/riscv/riscv-zacas
> > 
> > Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
> > Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
> > Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
> > ---
> >  target/riscv/cpu.c                          |   2 +
> >  target/riscv/cpu_cfg.h                      |   1 +
> >  target/riscv/insn32.decode                  |   6 +
> >  target/riscv/insn_trans/trans_rvzacas.c.inc | 150
> > ++++++++++++++++++++
> >  target/riscv/tcg/tcg-cpu.c                  |   5 +
> >  target/riscv/translate.c                    |   1 +
> >  6 files changed, 165 insertions(+)
> >  create mode 100644 target/riscv/insn_trans/trans_rvzacas.c.inc
> > 
> > diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> > index 83c7c0cf07..a265833b17 100644
> > --- a/target/riscv/cpu.c
> > +++ b/target/riscv/cpu.c
> > @@ -87,6 +87,7 @@ const RISCVIsaExtData isa_edata_arr[] = {
> >      ISA_EXT_DATA_ENTRY(zihintpause, PRIV_VERSION_1_10_0,
> > ext_zihintpause),
> >      ISA_EXT_DATA_ENTRY(zihpm, PRIV_VERSION_1_12_0, ext_zihpm),
> >      ISA_EXT_DATA_ENTRY(zmmul, PRIV_VERSION_1_12_0, ext_zmmul),
> > +    ISA_EXT_DATA_ENTRY(zacas, PRIV_VERSION_1_12_0, ext_zacas),
> >      ISA_EXT_DATA_ENTRY(zawrs, PRIV_VERSION_1_12_0, ext_zawrs),
> >      ISA_EXT_DATA_ENTRY(zfa, PRIV_VERSION_1_12_0, ext_zfa),
> >      ISA_EXT_DATA_ENTRY(zfbfmin, PRIV_VERSION_1_12_0, ext_zfbfmin),
> > @@ -1300,6 +1301,7 @@ const RISCVCPUMultiExtConfig
> > riscv_cpu_extensions[] = {
> >      MULTI_EXT_CFG_BOOL("zicsr", ext_zicsr, true),
> >      MULTI_EXT_CFG_BOOL("zihintntl", ext_zihintntl, true),
> >      MULTI_EXT_CFG_BOOL("zihintpause", ext_zihintpause, true),
> > +    MULTI_EXT_CFG_BOOL("zacas", ext_zacas, false),
> >      MULTI_EXT_CFG_BOOL("zawrs", ext_zawrs, true),
> >      MULTI_EXT_CFG_BOOL("zfa", ext_zfa, true),
> >      MULTI_EXT_CFG_BOOL("zfh", ext_zfh, false),
> > diff --git a/target/riscv/cpu_cfg.h b/target/riscv/cpu_cfg.h
> > index f4605fb190..d516de4a44 100644
> > --- a/target/riscv/cpu_cfg.h
> > +++ b/target/riscv/cpu_cfg.h
> > @@ -77,6 +77,7 @@ struct RISCVCPUConfig {
> >      bool ext_svnapot;
> >      bool ext_svpbmt;
> >      bool ext_zdinx;
> > +    bool ext_zacas;
> >      bool ext_zawrs;
> >      bool ext_zfa;
> >      bool ext_zfbfmin;
> > diff --git a/target/riscv/insn32.decode
> > b/target/riscv/insn32.decode
> > index 33597fe2bb..f22df04cfd 100644
> > --- a/target/riscv/insn32.decode
> > +++ b/target/riscv/insn32.decode
> > @@ -1004,3 +1004,9 @@ vgmul_vv    101000 1 ..... 10001 010 .....
> > 1110111 @r2_vm_1
> >  vsm4k_vi    100001 1 ..... ..... 010 ..... 1110111 @r_vm_1
> >  vsm4r_vv    101000 1 ..... 10000 010 ..... 1110111 @r2_vm_1
> >  vsm4r_vs    101001 1 ..... 10000 010 ..... 1110111 @r2_vm_1
> > +
> > +# *** RV32 Zacas Standard Extension ***
> > +amocas_w    00101 . . ..... ..... 010 ..... 0101111 @atom_st
> > +amocas_d    00101 . . ..... ..... 011 ..... 0101111 @atom_st
> > +# *** RV64 Zacas Standard Extension ***
> > +amocas_q    00101 . . ..... ..... 100 ..... 0101111 @atom_st
> > diff --git a/target/riscv/insn_trans/trans_rvzacas.c.inc
> > b/target/riscv/insn_trans/trans_rvzacas.c.inc
> > new file mode 100644
> > index 0000000000..5d274d4c08
> > --- /dev/null
> > +++ b/target/riscv/insn_trans/trans_rvzacas.c.inc
> > @@ -0,0 +1,150 @@
> > +/*
> > + * RISC-V translation routines for the RV64 Zacas Standard
> > Extension.
> > + *
> > + * Copyright (c) 2020-2023 PLCT Lab
> > + *
> > + * 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_ZACAS(ctx) do {          \
> > +    if (!ctx->cfg_ptr->ext_zacas) {      \
> > +        return false;                     \
> > +    }                                     \
> > +} while (0)
> > +
> > +static bool gen_cmpxchg(DisasContext *ctx, arg_atomic *a, MemOp
> > mop)
> > +{
> > +    TCGv dest = get_gpr(ctx, a->rd, EXT_NONE);
> > +    TCGv src1 = get_address(ctx, a->rs1, 0);
> > +    TCGv src2 = get_gpr(ctx, a->rs2, EXT_NONE);
> > +
> > +    decode_save_opc(ctx);
> > +    tcg_gen_atomic_cmpxchg_tl(dest, src1, dest, src2, ctx-
> > >mem_idx, mop);
> > +
> > +    gen_set_gpr(ctx, a->rd, dest);
> > +    return true;
> > +}
> > +
> > +static bool trans_amocas_w(DisasContext *ctx, arg_amocas_w *a)
> > +{
> > +    REQUIRE_ZACAS(ctx);
> > +    return gen_cmpxchg(ctx, a, MO_ALIGN | MO_TESL);
> > +}
> > +
> > +static TCGv_i64 get_gpr_pair(DisasContext *ctx, int reg_num)
> > +{
> > +    TCGv_i64 t;
> > +
> > +    assert(get_ol(ctx) == MXL_RV32);
> > +
> > +    if (reg_num == 0) {
> > +        return tcg_constant_i64(0);
> > +    }
> > +
> > +    t = tcg_temp_new_i64();
> > +    tcg_gen_concat_tl_i64(t, cpu_gpr[reg_num], cpu_gpr[reg_num +
> > 1]);
> > +    return t;
> > +}
> > +
> > +static void gen_set_gpr_pair(DisasContext *ctx, int reg_num,
> > TCGv_i64 t)
> > +{
> > +    assert(get_ol(ctx) == MXL_RV32);
> > +
> > +    if (reg_num != 0) {
> > +#ifdef TARGET_RISCV32
> > +        tcg_gen_extr_i64_i32(cpu_gpr[reg_num], cpu_gpr[reg_num +
> > 1], t);
> > +#else
> > +        tcg_gen_ext32s_i64(cpu_gpr[reg_num], t);
> > +        tcg_gen_sari_i64(cpu_gpr[reg_num + 1], t, 32);
> > +#endif
> 
> This should be dynamic based on the MXL.
> 

This function is already conditional on MXL = 32 as it us only called
from trans_amocas_d() when get_ol() == MXL_RV32 (there is an assertion
at the top to enforce this.) The compile time conditional code is
required as the cpu_gpr type (TCGv) changes between TCGv_i32 or
TCGv_i64 at build time - requiring different functions to be called to
split the value and assign to registers.

> > +
> > +        if (get_xl_max(ctx) == MXL_RV128) {
> > +            tcg_gen_sari_tl(cpu_gprh[reg_num], cpu_gpr[reg_num],
> > 63);
> > +            tcg_gen_sari_tl(cpu_gprh[reg_num + 1], cpu_gpr[reg_num
> > + 1], 63);
> > +        }
> > +    }
> > +}
> > +
> > +static bool gen_cmpxchg64(DisasContext *ctx, arg_atomic *a, MemOp
> > mop)
> > +{
> > +    /*
> > +     * Encodings with odd numbered registers specified in rs2 and
> > rd are
> > +     * reserved.
> > +     */
> > +    if ((a->rs2 | a->rd) & 1) {
> > +        return false;
> > +    }
> > +
> > +    TCGv_i64 dest = get_gpr_pair(ctx, a->rd);
> > +    TCGv src1 = get_address(ctx, a->rs1, 0);
> > +    TCGv_i64 src2 = get_gpr_pair(ctx, a->rs2);
> > +
> > +    decode_save_opc(ctx);
> > +    tcg_gen_atomic_cmpxchg_i64(dest, src1, dest, src2, ctx-
> > >mem_idx, mop);
> > +
> > +    gen_set_gpr_pair(ctx, a->rd, dest);
> > +    return true;
> > +}
> > +
> > +static bool trans_amocas_d(DisasContext *ctx, arg_amocas_d *a)
> > +{
> > +    REQUIRE_ZACAS(ctx);
> > +    switch (get_ol(ctx)) {
> > +    case MXL_RV32:
> > +        return gen_cmpxchg64(ctx, a, MO_ALIGN | MO_TEUQ);
> > +    case MXL_RV64:
> > +    case MXL_RV128:
> > +        return gen_cmpxchg(ctx, a, MO_ALIGN | MO_TEUQ);
> > +    default:
> > +        g_assert_not_reached();
> > +    }
> > +}
> > +
> > +static bool trans_amocas_q(DisasContext *ctx, arg_amocas_q *a)
> > +{
> > +    REQUIRE_ZACAS(ctx);
> > +    REQUIRE_64BIT(ctx);
> > +
> > +    /*
> > +     * Encodings with odd numbered registers specified in rs2 and
> > rd are
> > +     * reserved.
> > +     */
> > +    if ((a->rs2 | a->rd) & 1) {
> > +        return false;
> > +    }
> > +
> > +#ifdef TARGET_RISCV64
> 
> We already have a REQUIRE_64BIT(ctx), do we need this as well?
> 

Unfortunately yes, because when compiling under TARGET_RISCV32 there is
a type mismatch error from the get_gpr() method - similar to the
requirement to have two paths in the gen_cmpxchg64() function: e.g. to
concatenate the two TGV_i64 to a TGV_i128 the datatype from get_gpr()
must be TGV_i64.

The REQUIRE_6BIT() provides the necessary check at runtime to check
that we are running with MXL = 64.

Cheers,

Rob

> Alistair
> 
> > +    TCGv_i128 dest = tcg_temp_new_i128();
> > +    TCGv src1 = get_address(ctx, a->rs1, 0);
> > +    TCGv_i128 src2 = tcg_temp_new_i128();
> > +    TCGv_i64 src2l = get_gpr(ctx, a->rs2, EXT_NONE);
> > +    TCGv_i64 src2h = get_gpr(ctx, a->rs2 == 0 ? 0 : a->rs2 + 1,
> > EXT_NONE);
> > +    TCGv_i64 destl = get_gpr(ctx, a->rd, EXT_NONE);
> > +    TCGv_i64 desth = get_gpr(ctx, a->rd == 0 ? 0 : a->rd + 1,
> > EXT_NONE);
> > +
> > +    tcg_gen_concat_i64_i128(src2, src2l, src2h);
> > +    tcg_gen_concat_i64_i128(dest, destl, desth);
> > +    decode_save_opc(ctx);
> > +    tcg_gen_atomic_cmpxchg_i128(dest, src1, dest, src2, ctx-
> > >mem_idx,
> > +                                (MO_ALIGN | MO_TEUO));
> > +
> > +    tcg_gen_extr_i128_i64(destl, desth, dest);
> > +
> > +    if (a->rd != 0) {
> > +        gen_set_gpr(ctx, a->rd, destl);
> > +        gen_set_gpr(ctx, a->rd + 1, desth);
> > +    }
> > +#endif
> > +
> > +    return true;
> > +}
> > diff --git a/target/riscv/tcg/tcg-cpu.c b/target/riscv/tcg/tcg-
> > cpu.c
> > index 8a35683a34..29b5a88931 100644
> > --- a/target/riscv/tcg/tcg-cpu.c
> > +++ b/target/riscv/tcg/tcg-cpu.c
> > @@ -343,6 +343,11 @@ void
> > riscv_cpu_validate_set_extensions(RISCVCPU *cpu, Error **errp)
> >          return;
> >      }
> > 
> > +    if ((cpu->cfg.ext_zacas) && !riscv_has_ext(env, RVA)) {
> > +        error_setg(errp, "Zacas extension requires A extension");
> > +        return;
> > +    }
> > +
> >      if ((cpu->cfg.ext_zawrs) && !riscv_has_ext(env, RVA)) {
> >          error_setg(errp, "Zawrs extension requires A extension");
> >          return;
> > diff --git a/target/riscv/translate.c b/target/riscv/translate.c
> > index f0be79bb16..071fbad7ef 100644
> > --- a/target/riscv/translate.c
> > +++ b/target/riscv/translate.c
> > @@ -1089,6 +1089,7 @@ static uint32_t opcode_at(DisasContextBase
> > *dcbase, target_ulong pc)
> >  #include "insn_trans/trans_rvv.c.inc"
> >  #include "insn_trans/trans_rvb.c.inc"
> >  #include "insn_trans/trans_rvzicond.c.inc"
> > +#include "insn_trans/trans_rvzacas.c.inc"
> >  #include "insn_trans/trans_rvzawrs.c.inc"
> >  #include "insn_trans/trans_rvzicbo.c.inc"
> >  #include "insn_trans/trans_rvzfa.c.inc"
> > --
> > 2.43.0
> > 
> > 

Re: [PATCH 1/2] target/riscv: Add support for Zacas extension

[Alistair Francis]

On Fri, Dec 8, 2023 at 1:40 AM Rob Bradford <rbradford@rivosinc.com> wrote:
>
> From: Weiwei Li <liweiwei@iscas.ac.cn>
>
> Add support for amocas.w/d/q instructions which are part of the ratified
> Zacas extension: https://github.com/riscv/riscv-zacas
>
> Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
> Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
> Signed-off-by: Rob Bradford <rbradford@rivosinc.com>

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Alistair

> ---
>  target/riscv/cpu.c                          |   2 +
>  target/riscv/cpu_cfg.h                      |   1 +
>  target/riscv/insn32.decode                  |   6 +
>  target/riscv/insn_trans/trans_rvzacas.c.inc | 150 ++++++++++++++++++++
>  target/riscv/tcg/tcg-cpu.c                  |   5 +
>  target/riscv/translate.c                    |   1 +
>  6 files changed, 165 insertions(+)
>  create mode 100644 target/riscv/insn_trans/trans_rvzacas.c.inc
>
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index 83c7c0cf07..a265833b17 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -87,6 +87,7 @@ const RISCVIsaExtData isa_edata_arr[] = {
>      ISA_EXT_DATA_ENTRY(zihintpause, PRIV_VERSION_1_10_0, ext_zihintpause),
>      ISA_EXT_DATA_ENTRY(zihpm, PRIV_VERSION_1_12_0, ext_zihpm),
>      ISA_EXT_DATA_ENTRY(zmmul, PRIV_VERSION_1_12_0, ext_zmmul),
> +    ISA_EXT_DATA_ENTRY(zacas, PRIV_VERSION_1_12_0, ext_zacas),
>      ISA_EXT_DATA_ENTRY(zawrs, PRIV_VERSION_1_12_0, ext_zawrs),
>      ISA_EXT_DATA_ENTRY(zfa, PRIV_VERSION_1_12_0, ext_zfa),
>      ISA_EXT_DATA_ENTRY(zfbfmin, PRIV_VERSION_1_12_0, ext_zfbfmin),
> @@ -1300,6 +1301,7 @@ const RISCVCPUMultiExtConfig riscv_cpu_extensions[] = {
>      MULTI_EXT_CFG_BOOL("zicsr", ext_zicsr, true),
>      MULTI_EXT_CFG_BOOL("zihintntl", ext_zihintntl, true),
>      MULTI_EXT_CFG_BOOL("zihintpause", ext_zihintpause, true),
> +    MULTI_EXT_CFG_BOOL("zacas", ext_zacas, false),
>      MULTI_EXT_CFG_BOOL("zawrs", ext_zawrs, true),
>      MULTI_EXT_CFG_BOOL("zfa", ext_zfa, true),
>      MULTI_EXT_CFG_BOOL("zfh", ext_zfh, false),
> diff --git a/target/riscv/cpu_cfg.h b/target/riscv/cpu_cfg.h
> index f4605fb190..d516de4a44 100644
> --- a/target/riscv/cpu_cfg.h
> +++ b/target/riscv/cpu_cfg.h
> @@ -77,6 +77,7 @@ struct RISCVCPUConfig {
>      bool ext_svnapot;
>      bool ext_svpbmt;
>      bool ext_zdinx;
> +    bool ext_zacas;
>      bool ext_zawrs;
>      bool ext_zfa;
>      bool ext_zfbfmin;
> diff --git a/target/riscv/insn32.decode b/target/riscv/insn32.decode
> index 33597fe2bb..f22df04cfd 100644
> --- a/target/riscv/insn32.decode
> +++ b/target/riscv/insn32.decode
> @@ -1004,3 +1004,9 @@ vgmul_vv    101000 1 ..... 10001 010 ..... 1110111 @r2_vm_1
>  vsm4k_vi    100001 1 ..... ..... 010 ..... 1110111 @r_vm_1
>  vsm4r_vv    101000 1 ..... 10000 010 ..... 1110111 @r2_vm_1
>  vsm4r_vs    101001 1 ..... 10000 010 ..... 1110111 @r2_vm_1
> +
> +# *** RV32 Zacas Standard Extension ***
> +amocas_w    00101 . . ..... ..... 010 ..... 0101111 @atom_st
> +amocas_d    00101 . . ..... ..... 011 ..... 0101111 @atom_st
> +# *** RV64 Zacas Standard Extension ***
> +amocas_q    00101 . . ..... ..... 100 ..... 0101111 @atom_st
> diff --git a/target/riscv/insn_trans/trans_rvzacas.c.inc b/target/riscv/insn_trans/trans_rvzacas.c.inc
> new file mode 100644
> index 0000000000..5d274d4c08
> --- /dev/null
> +++ b/target/riscv/insn_trans/trans_rvzacas.c.inc
> @@ -0,0 +1,150 @@
> +/*
> + * RISC-V translation routines for the RV64 Zacas Standard Extension.
> + *
> + * Copyright (c) 2020-2023 PLCT Lab
> + *
> + * 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_ZACAS(ctx) do {          \
> +    if (!ctx->cfg_ptr->ext_zacas) {      \
> +        return false;                     \
> +    }                                     \
> +} while (0)
> +
> +static bool gen_cmpxchg(DisasContext *ctx, arg_atomic *a, MemOp mop)
> +{
> +    TCGv dest = get_gpr(ctx, a->rd, EXT_NONE);
> +    TCGv src1 = get_address(ctx, a->rs1, 0);
> +    TCGv src2 = get_gpr(ctx, a->rs2, EXT_NONE);
> +
> +    decode_save_opc(ctx);
> +    tcg_gen_atomic_cmpxchg_tl(dest, src1, dest, src2, ctx->mem_idx, mop);
> +
> +    gen_set_gpr(ctx, a->rd, dest);
> +    return true;
> +}
> +
> +static bool trans_amocas_w(DisasContext *ctx, arg_amocas_w *a)
> +{
> +    REQUIRE_ZACAS(ctx);
> +    return gen_cmpxchg(ctx, a, MO_ALIGN | MO_TESL);
> +}
> +
> +static TCGv_i64 get_gpr_pair(DisasContext *ctx, int reg_num)
> +{
> +    TCGv_i64 t;
> +
> +    assert(get_ol(ctx) == MXL_RV32);
> +
> +    if (reg_num == 0) {
> +        return tcg_constant_i64(0);
> +    }
> +
> +    t = tcg_temp_new_i64();
> +    tcg_gen_concat_tl_i64(t, cpu_gpr[reg_num], cpu_gpr[reg_num + 1]);
> +    return t;
> +}
> +
> +static void gen_set_gpr_pair(DisasContext *ctx, int reg_num, TCGv_i64 t)
> +{
> +    assert(get_ol(ctx) == MXL_RV32);
> +
> +    if (reg_num != 0) {
> +#ifdef TARGET_RISCV32
> +        tcg_gen_extr_i64_i32(cpu_gpr[reg_num], cpu_gpr[reg_num + 1], t);
> +#else
> +        tcg_gen_ext32s_i64(cpu_gpr[reg_num], t);
> +        tcg_gen_sari_i64(cpu_gpr[reg_num + 1], t, 32);
> +#endif
> +
> +        if (get_xl_max(ctx) == MXL_RV128) {
> +            tcg_gen_sari_tl(cpu_gprh[reg_num], cpu_gpr[reg_num], 63);
> +            tcg_gen_sari_tl(cpu_gprh[reg_num + 1], cpu_gpr[reg_num + 1], 63);
> +        }
> +    }
> +}
> +
> +static bool gen_cmpxchg64(DisasContext *ctx, arg_atomic *a, MemOp mop)
> +{
> +    /*
> +     * Encodings with odd numbered registers specified in rs2 and rd are
> +     * reserved.
> +     */
> +    if ((a->rs2 | a->rd) & 1) {
> +        return false;
> +    }
> +
> +    TCGv_i64 dest = get_gpr_pair(ctx, a->rd);
> +    TCGv src1 = get_address(ctx, a->rs1, 0);
> +    TCGv_i64 src2 = get_gpr_pair(ctx, a->rs2);
> +
> +    decode_save_opc(ctx);
> +    tcg_gen_atomic_cmpxchg_i64(dest, src1, dest, src2, ctx->mem_idx, mop);
> +
> +    gen_set_gpr_pair(ctx, a->rd, dest);
> +    return true;
> +}
> +
> +static bool trans_amocas_d(DisasContext *ctx, arg_amocas_d *a)
> +{
> +    REQUIRE_ZACAS(ctx);
> +    switch (get_ol(ctx)) {
> +    case MXL_RV32:
> +        return gen_cmpxchg64(ctx, a, MO_ALIGN | MO_TEUQ);
> +    case MXL_RV64:
> +    case MXL_RV128:
> +        return gen_cmpxchg(ctx, a, MO_ALIGN | MO_TEUQ);
> +    default:
> +        g_assert_not_reached();
> +    }
> +}
> +
> +static bool trans_amocas_q(DisasContext *ctx, arg_amocas_q *a)
> +{
> +    REQUIRE_ZACAS(ctx);
> +    REQUIRE_64BIT(ctx);
> +
> +    /*
> +     * Encodings with odd numbered registers specified in rs2 and rd are
> +     * reserved.
> +     */
> +    if ((a->rs2 | a->rd) & 1) {
> +        return false;
> +    }
> +
> +#ifdef TARGET_RISCV64
> +    TCGv_i128 dest = tcg_temp_new_i128();
> +    TCGv src1 = get_address(ctx, a->rs1, 0);
> +    TCGv_i128 src2 = tcg_temp_new_i128();
> +    TCGv_i64 src2l = get_gpr(ctx, a->rs2, EXT_NONE);
> +    TCGv_i64 src2h = get_gpr(ctx, a->rs2 == 0 ? 0 : a->rs2 + 1, EXT_NONE);
> +    TCGv_i64 destl = get_gpr(ctx, a->rd, EXT_NONE);
> +    TCGv_i64 desth = get_gpr(ctx, a->rd == 0 ? 0 : a->rd + 1, EXT_NONE);
> +
> +    tcg_gen_concat_i64_i128(src2, src2l, src2h);
> +    tcg_gen_concat_i64_i128(dest, destl, desth);
> +    decode_save_opc(ctx);
> +    tcg_gen_atomic_cmpxchg_i128(dest, src1, dest, src2, ctx->mem_idx,
> +                                (MO_ALIGN | MO_TEUO));
> +
> +    tcg_gen_extr_i128_i64(destl, desth, dest);
> +
> +    if (a->rd != 0) {
> +        gen_set_gpr(ctx, a->rd, destl);
> +        gen_set_gpr(ctx, a->rd + 1, desth);
> +    }
> +#endif
> +
> +    return true;
> +}
> diff --git a/target/riscv/tcg/tcg-cpu.c b/target/riscv/tcg/tcg-cpu.c
> index 8a35683a34..29b5a88931 100644
> --- a/target/riscv/tcg/tcg-cpu.c
> +++ b/target/riscv/tcg/tcg-cpu.c
> @@ -343,6 +343,11 @@ void riscv_cpu_validate_set_extensions(RISCVCPU *cpu, Error **errp)
>          return;
>      }
>
> +    if ((cpu->cfg.ext_zacas) && !riscv_has_ext(env, RVA)) {
> +        error_setg(errp, "Zacas extension requires A extension");
> +        return;
> +    }
> +
>      if ((cpu->cfg.ext_zawrs) && !riscv_has_ext(env, RVA)) {
>          error_setg(errp, "Zawrs extension requires A extension");
>          return;
> diff --git a/target/riscv/translate.c b/target/riscv/translate.c
> index f0be79bb16..071fbad7ef 100644
> --- a/target/riscv/translate.c
> +++ b/target/riscv/translate.c
> @@ -1089,6 +1089,7 @@ static uint32_t opcode_at(DisasContextBase *dcbase, target_ulong pc)
>  #include "insn_trans/trans_rvv.c.inc"
>  #include "insn_trans/trans_rvb.c.inc"
>  #include "insn_trans/trans_rvzicond.c.inc"
> +#include "insn_trans/trans_rvzacas.c.inc"
>  #include "insn_trans/trans_rvzawrs.c.inc"
>  #include "insn_trans/trans_rvzicbo.c.inc"
>  #include "insn_trans/trans_rvzfa.c.inc"
> --
> 2.43.0
>
>

Re: [PATCH 0/2] Add support for (ratified) Zacas extension

[Alistair Francis]

On Fri, Dec 8, 2023 at 1:40 AM Rob Bradford <rbradford@rivosinc.com> wrote:
>
> The Zacas extension is now ratified:
> https://github.com/riscv/riscv-zacas
>
> This series uses a patch from Weiwei Li from:
> https://github.com/plctlab/plct-qemu/tree/plct-zacas-dev with the
> following changes:
>
> * Fixed destination register (looks like a copy and paste error),
> * Fixed extension name enabling,
> * Minor coding style fixes,
> * Updated for new extension handling & cpu.h header split.
>
> This patch was mentioned on the list here:
> https://www.mail-archive.com/qemu-devel@nongnu.org/msg970280.html
>
> The series was tested against riscv-tests from the following PR:
> https://github.com/riscv-software-src/riscv-tests/pull/492
>
> Rob Bradford (1):
>   disas/riscv: Add amocas.[w,d,q] instructions
>
> Weiwei Li (1):
>   target/riscv: Add support for Zacas extension

Thanks!

Applied to riscv-to-apply.next

Alistair

>
>  disas/riscv.c                               |   9 ++
>  target/riscv/cpu.c                          |   2 +
>  target/riscv/cpu_cfg.h                      |   1 +
>  target/riscv/insn32.decode                  |   6 +
>  target/riscv/insn_trans/trans_rvzacas.c.inc | 150 ++++++++++++++++++++
>  target/riscv/tcg/tcg-cpu.c                  |   5 +
>  target/riscv/translate.c                    |   1 +
>  7 files changed, 174 insertions(+)
>  create mode 100644 target/riscv/insn_trans/trans_rvzacas.c.inc
>
> --
> 2.43.0
>
>