diff mbox series

[v2,1/2] target/riscv: add Zicond as an experimental extension

Message ID 20230121023542.1726168-1-philipp.tomsich@vrull.eu (mailing list archive)
State New, archived
Headers show
Series [v2,1/2] target/riscv: add Zicond as an experimental extension | expand

Commit Message

Philipp Tomsich Jan. 21, 2023, 2:35 a.m. UTC
This implements the Zicond (conditional integer operations) extension,
as of version 1.0-draft-20230120 as an experimental extension in QEMU
("x-zicond").

The Zicond extension acts as a building block for branchless sequences
including conditional-{arithmetic,logic,select,move}.  Refer to the
specification for usage scenarios and application guidance.

The following instructions constitute Zicond:
  - czero.eqz rd, rs1, rs2  =>  rd = (rs2 == 0) ? 0 : rs1
  - czero.nez rd, rs1, rs2  =>  rd = (rs2 != 0) ? 0 : rs1

See
  https://github.com/riscv/riscv-zicond/releases/download/v1.0-draft-20230120/riscv-zicond_1.0-draft-20230120.pdf
for the (current version of the) Zicond specification and usage details.

Signed-off-by: Philipp Tomsich <philipp.tomsich@vrull.eu>
---

Changes in v2:
- gates availability of the instructions through a REQUIRE_ZICOND
  macro (these were previously always enabled)

 MAINTAINERS                                  |  7 +++
 target/riscv/cpu.c                           |  4 ++
 target/riscv/cpu.h                           |  1 +
 target/riscv/insn32.decode                   |  4 ++
 target/riscv/insn_trans/trans_rvzicond.c.inc | 54 ++++++++++++++++++++
 target/riscv/translate.c                     |  1 +
 6 files changed, 71 insertions(+)
 create mode 100644 target/riscv/insn_trans/trans_rvzicond.c.inc

Comments

Alistair Francis Jan. 23, 2023, 1:28 a.m. UTC | #1
On Sat, Jan 21, 2023 at 12:36 PM Philipp Tomsich
<philipp.tomsich@vrull.eu> wrote:
>
> This implements the Zicond (conditional integer operations) extension,
> as of version 1.0-draft-20230120 as an experimental extension in QEMU
> ("x-zicond").
>
> The Zicond extension acts as a building block for branchless sequences
> including conditional-{arithmetic,logic,select,move}.  Refer to the
> specification for usage scenarios and application guidance.
>
> The following instructions constitute Zicond:
>   - czero.eqz rd, rs1, rs2  =>  rd = (rs2 == 0) ? 0 : rs1
>   - czero.nez rd, rs1, rs2  =>  rd = (rs2 != 0) ? 0 : rs1
>
> See
>   https://github.com/riscv/riscv-zicond/releases/download/v1.0-draft-20230120/riscv-zicond_1.0-draft-20230120.pdf
> for the (current version of the) Zicond specification and usage details.
>
> Signed-off-by: Philipp Tomsich <philipp.tomsich@vrull.eu>
> ---
>
> Changes in v2:
> - gates availability of the instructions through a REQUIRE_ZICOND
>   macro (these were previously always enabled)
>
>  MAINTAINERS                                  |  7 +++
>  target/riscv/cpu.c                           |  4 ++
>  target/riscv/cpu.h                           |  1 +
>  target/riscv/insn32.decode                   |  4 ++
>  target/riscv/insn_trans/trans_rvzicond.c.inc | 54 ++++++++++++++++++++
>  target/riscv/translate.c                     |  1 +
>  6 files changed, 71 insertions(+)
>  create mode 100644 target/riscv/insn_trans/trans_rvzicond.c.inc
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 08ad1e5341..ca914c42fa 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -295,6 +295,13 @@ F: include/hw/riscv/
>  F: linux-user/host/riscv32/
>  F: linux-user/host/riscv64/
>
> +RISC-V Zicond extension
> +M: Philipp Tomsich <philipp.tomsich@vrull.eu>
> +M: Christoph Muellner <christoph.muellner@vrull.eu>
> +L: qemu-riscv@nongnu.org
> +S: Supported
> +F: target/riscv/insn_trans/trans_zicond.c.inc

I don't think we need a maintainers entry for official extensions,
that seems like it's going to get out of hand very quickly.

Alistair

> +
>  RISC-V XVentanaCondOps extension
>  M: Philipp Tomsich <philipp.tomsich@vrull.eu>
>  L: qemu-riscv@nongnu.org
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index cc75ca7667..f214b03e95 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -73,6 +73,7 @@ struct isa_ext_data {
>  static const struct isa_ext_data isa_edata_arr[] = {
>      ISA_EXT_DATA_ENTRY(h, false, PRIV_VERSION_1_12_0, ext_h),
>      ISA_EXT_DATA_ENTRY(v, false, PRIV_VERSION_1_12_0, ext_v),
> +    ISA_EXT_DATA_ENTRY(zicond, true, PRIV_VERSION_1_12_0, ext_zicond),
>      ISA_EXT_DATA_ENTRY(zicsr, true, PRIV_VERSION_1_10_0, ext_icsr),
>      ISA_EXT_DATA_ENTRY(zifencei, true, PRIV_VERSION_1_10_0, ext_ifencei),
>      ISA_EXT_DATA_ENTRY(zihintpause, true, PRIV_VERSION_1_10_0, ext_zihintpause),
> @@ -1080,6 +1081,9 @@ static Property riscv_cpu_extensions[] = {
>      DEFINE_PROP_BOOL("x-smaia", RISCVCPU, cfg.ext_smaia, false),
>      DEFINE_PROP_BOOL("x-ssaia", RISCVCPU, cfg.ext_ssaia, false),
>
> +    /* Zicond 1.0-draft-20230120 */
> +    DEFINE_PROP_BOOL("x-zicond", RISCVCPU, cfg.ext_zicond, false),
> +
>      DEFINE_PROP_END_OF_LIST(),
>  };
>
> diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> index f5609b62a2..4b6ff800d3 100644
> --- a/target/riscv/cpu.h
> +++ b/target/riscv/cpu.h
> @@ -446,6 +446,7 @@ struct RISCVCPUConfig {
>      bool ext_zkt;
>      bool ext_ifencei;
>      bool ext_icsr;
> +    bool ext_zicond;
>      bool ext_zihintpause;
>      bool ext_smstateen;
>      bool ext_sstc;
> diff --git a/target/riscv/insn32.decode b/target/riscv/insn32.decode
> index b7e7613ea2..ca812c2f7a 100644
> --- a/target/riscv/insn32.decode
> +++ b/target/riscv/insn32.decode
> @@ -890,3 +890,7 @@ sm3p1       00 01000 01001 ..... 001 ..... 0010011 @r2
>  # *** RV32 Zksed Standard Extension ***
>  sm4ed       .. 11000 ..... ..... 000 ..... 0110011 @k_aes
>  sm4ks       .. 11010 ..... ..... 000 ..... 0110011 @k_aes
> +
> +# *** Zicond Standard Extension ***
> +czero_eqz   0000111 ..... ..... 101 ..... 0110011 @r
> +czero_nez   0000111 ..... ..... 111 ..... 0110011 @r
> diff --git a/target/riscv/insn_trans/trans_rvzicond.c.inc b/target/riscv/insn_trans/trans_rvzicond.c.inc
> new file mode 100644
> index 0000000000..20e9694a2c
> --- /dev/null
> +++ b/target/riscv/insn_trans/trans_rvzicond.c.inc
> @@ -0,0 +1,54 @@
> +/*
> + * RISC-V translation routines for the XVentanaCondOps extension.
> + *
> + * Copyright (c) 2022 VRULL GmbH.
> + *
> + * 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_ZICOND(ctx) do {                 \
> +    if (!ctx->cfg_ptr->ext_zicond) {             \
> +        return false;                            \
> +    }                                            \
> +} while (0)
> +
> +/* Emits "$rd = ($rs2 <cond> $zero) ? $zero : $rs1" */
> +static inline void gen_czero(TCGv dest, TCGv src1, TCGv src2, TCGCond cond)
> +{
> +    TCGv zero = tcg_constant_tl(0);
> +    tcg_gen_movcond_tl(cond, dest, src2, zero, zero, src1);
> +}
> +
> +static inline void gen_czero_eqz(TCGv dest, TCGv src1, TCGv src2)
> +{
> +    gen_czero(dest, src1, src2, TCG_COND_EQ);
> +}
> +
> +static inline void gen_czero_nez(TCGv dest, TCGv src1, TCGv src2)
> +{
> +    gen_czero(dest, src1, src2, TCG_COND_NE);
> +}
> +
> +static bool trans_czero_eqz(DisasContext *ctx, arg_r *a)
> +{
> +    REQUIRE_ZICOND(ctx);
> +
> +    return gen_logic(ctx, a, gen_czero_eqz);
> +}
> +
> +static bool trans_czero_nez(DisasContext *ctx, arg_r *a)
> +{
> +    REQUIRE_ZICOND(ctx);
> +
> +    return gen_logic(ctx, a, gen_czero_nez);
> +}
> diff --git a/target/riscv/translate.c b/target/riscv/translate.c
> index df38db7553..1468748835 100644
> --- a/target/riscv/translate.c
> +++ b/target/riscv/translate.c
> @@ -1061,6 +1061,7 @@ 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_rvzawrs.c.inc"
> +#include "insn_trans/trans_rvzicond.c.inc"
>  #include "insn_trans/trans_rvzfh.c.inc"
>  #include "insn_trans/trans_rvk.c.inc"
>  #include "insn_trans/trans_privileged.c.inc"
> --
> 2.34.1
>
>
Philipp Tomsich Jan. 23, 2023, 1:32 a.m. UTC | #2
On Mon, 23 Jan 2023 at 02:28, Alistair Francis <alistair23@gmail.com> wrote:
>
> On Sat, Jan 21, 2023 at 12:36 PM Philipp Tomsich
> <philipp.tomsich@vrull.eu> wrote:
> >
> > This implements the Zicond (conditional integer operations) extension,
> > as of version 1.0-draft-20230120 as an experimental extension in QEMU
> > ("x-zicond").
> >
> > The Zicond extension acts as a building block for branchless sequences
> > including conditional-{arithmetic,logic,select,move}.  Refer to the
> > specification for usage scenarios and application guidance.
> >
> > The following instructions constitute Zicond:
> >   - czero.eqz rd, rs1, rs2  =>  rd = (rs2 == 0) ? 0 : rs1
> >   - czero.nez rd, rs1, rs2  =>  rd = (rs2 != 0) ? 0 : rs1
> >
> > See
> >   https://github.com/riscv/riscv-zicond/releases/download/v1.0-draft-20230120/riscv-zicond_1.0-draft-20230120.pdf
> > for the (current version of the) Zicond specification and usage details.
> >
> > Signed-off-by: Philipp Tomsich <philipp.tomsich@vrull.eu>
> > ---
> >
> > Changes in v2:
> > - gates availability of the instructions through a REQUIRE_ZICOND
> >   macro (these were previously always enabled)
> >
> >  MAINTAINERS                                  |  7 +++
> >  target/riscv/cpu.c                           |  4 ++
> >  target/riscv/cpu.h                           |  1 +
> >  target/riscv/insn32.decode                   |  4 ++
> >  target/riscv/insn_trans/trans_rvzicond.c.inc | 54 ++++++++++++++++++++
> >  target/riscv/translate.c                     |  1 +
> >  6 files changed, 71 insertions(+)
> >  create mode 100644 target/riscv/insn_trans/trans_rvzicond.c.inc
> >
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 08ad1e5341..ca914c42fa 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -295,6 +295,13 @@ F: include/hw/riscv/
> >  F: linux-user/host/riscv32/
> >  F: linux-user/host/riscv64/
> >
> > +RISC-V Zicond extension
> > +M: Philipp Tomsich <philipp.tomsich@vrull.eu>
> > +M: Christoph Muellner <christoph.muellner@vrull.eu>
> > +L: qemu-riscv@nongnu.org
> > +S: Supported
> > +F: target/riscv/insn_trans/trans_zicond.c.inc
>
> I don't think we need a maintainers entry for official extensions,
> that seems like it's going to get out of hand very quickly.


I'll drop on v3 — or feel free to edit it out when merging.
I put this in, as Zicond is unratified and I put it in as a commitment
to handle this until ratified.

Cheers,
Philipp.

>
> > +
> >  RISC-V XVentanaCondOps extension
> >  M: Philipp Tomsich <philipp.tomsich@vrull.eu>
> >  L: qemu-riscv@nongnu.org
> > diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> > index cc75ca7667..f214b03e95 100644
> > --- a/target/riscv/cpu.c
> > +++ b/target/riscv/cpu.c
> > @@ -73,6 +73,7 @@ struct isa_ext_data {
> >  static const struct isa_ext_data isa_edata_arr[] = {
> >      ISA_EXT_DATA_ENTRY(h, false, PRIV_VERSION_1_12_0, ext_h),
> >      ISA_EXT_DATA_ENTRY(v, false, PRIV_VERSION_1_12_0, ext_v),
> > +    ISA_EXT_DATA_ENTRY(zicond, true, PRIV_VERSION_1_12_0, ext_zicond),
> >      ISA_EXT_DATA_ENTRY(zicsr, true, PRIV_VERSION_1_10_0, ext_icsr),
> >      ISA_EXT_DATA_ENTRY(zifencei, true, PRIV_VERSION_1_10_0, ext_ifencei),
> >      ISA_EXT_DATA_ENTRY(zihintpause, true, PRIV_VERSION_1_10_0, ext_zihintpause),
> > @@ -1080,6 +1081,9 @@ static Property riscv_cpu_extensions[] = {
> >      DEFINE_PROP_BOOL("x-smaia", RISCVCPU, cfg.ext_smaia, false),
> >      DEFINE_PROP_BOOL("x-ssaia", RISCVCPU, cfg.ext_ssaia, false),
> >
> > +    /* Zicond 1.0-draft-20230120 */
> > +    DEFINE_PROP_BOOL("x-zicond", RISCVCPU, cfg.ext_zicond, false),
> > +
> >      DEFINE_PROP_END_OF_LIST(),
> >  };
> >
> > diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> > index f5609b62a2..4b6ff800d3 100644
> > --- a/target/riscv/cpu.h
> > +++ b/target/riscv/cpu.h
> > @@ -446,6 +446,7 @@ struct RISCVCPUConfig {
> >      bool ext_zkt;
> >      bool ext_ifencei;
> >      bool ext_icsr;
> > +    bool ext_zicond;
> >      bool ext_zihintpause;
> >      bool ext_smstateen;
> >      bool ext_sstc;
> > diff --git a/target/riscv/insn32.decode b/target/riscv/insn32.decode
> > index b7e7613ea2..ca812c2f7a 100644
> > --- a/target/riscv/insn32.decode
> > +++ b/target/riscv/insn32.decode
> > @@ -890,3 +890,7 @@ sm3p1       00 01000 01001 ..... 001 ..... 0010011 @r2
> >  # *** RV32 Zksed Standard Extension ***
> >  sm4ed       .. 11000 ..... ..... 000 ..... 0110011 @k_aes
> >  sm4ks       .. 11010 ..... ..... 000 ..... 0110011 @k_aes
> > +
> > +# *** Zicond Standard Extension ***
> > +czero_eqz   0000111 ..... ..... 101 ..... 0110011 @r
> > +czero_nez   0000111 ..... ..... 111 ..... 0110011 @r
> > diff --git a/target/riscv/insn_trans/trans_rvzicond.c.inc b/target/riscv/insn_trans/trans_rvzicond.c.inc
> > new file mode 100644
> > index 0000000000..20e9694a2c
> > --- /dev/null
> > +++ b/target/riscv/insn_trans/trans_rvzicond.c.inc
> > @@ -0,0 +1,54 @@
> > +/*
> > + * RISC-V translation routines for the XVentanaCondOps extension.
> > + *
> > + * Copyright (c) 2022 VRULL GmbH.
> > + *
> > + * 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_ZICOND(ctx) do {                 \
> > +    if (!ctx->cfg_ptr->ext_zicond) {             \
> > +        return false;                            \
> > +    }                                            \
> > +} while (0)
> > +
> > +/* Emits "$rd = ($rs2 <cond> $zero) ? $zero : $rs1" */
> > +static inline void gen_czero(TCGv dest, TCGv src1, TCGv src2, TCGCond cond)
> > +{
> > +    TCGv zero = tcg_constant_tl(0);
> > +    tcg_gen_movcond_tl(cond, dest, src2, zero, zero, src1);
> > +}
> > +
> > +static inline void gen_czero_eqz(TCGv dest, TCGv src1, TCGv src2)
> > +{
> > +    gen_czero(dest, src1, src2, TCG_COND_EQ);
> > +}
> > +
> > +static inline void gen_czero_nez(TCGv dest, TCGv src1, TCGv src2)
> > +{
> > +    gen_czero(dest, src1, src2, TCG_COND_NE);
> > +}
> > +
> > +static bool trans_czero_eqz(DisasContext *ctx, arg_r *a)
> > +{
> > +    REQUIRE_ZICOND(ctx);
> > +
> > +    return gen_logic(ctx, a, gen_czero_eqz);
> > +}
> > +
> > +static bool trans_czero_nez(DisasContext *ctx, arg_r *a)
> > +{
> > +    REQUIRE_ZICOND(ctx);
> > +
> > +    return gen_logic(ctx, a, gen_czero_nez);
> > +}
> > diff --git a/target/riscv/translate.c b/target/riscv/translate.c
> > index df38db7553..1468748835 100644
> > --- a/target/riscv/translate.c
> > +++ b/target/riscv/translate.c
> > @@ -1061,6 +1061,7 @@ 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_rvzawrs.c.inc"
> > +#include "insn_trans/trans_rvzicond.c.inc"
> >  #include "insn_trans/trans_rvzfh.c.inc"
> >  #include "insn_trans/trans_rvk.c.inc"
> >  #include "insn_trans/trans_privileged.c.inc"
> > --
> > 2.34.1
> >
> >
diff mbox series

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index 08ad1e5341..ca914c42fa 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -295,6 +295,13 @@  F: include/hw/riscv/
 F: linux-user/host/riscv32/
 F: linux-user/host/riscv64/
 
+RISC-V Zicond extension
+M: Philipp Tomsich <philipp.tomsich@vrull.eu>
+M: Christoph Muellner <christoph.muellner@vrull.eu>
+L: qemu-riscv@nongnu.org
+S: Supported
+F: target/riscv/insn_trans/trans_zicond.c.inc
+
 RISC-V XVentanaCondOps extension
 M: Philipp Tomsich <philipp.tomsich@vrull.eu>
 L: qemu-riscv@nongnu.org
diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index cc75ca7667..f214b03e95 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -73,6 +73,7 @@  struct isa_ext_data {
 static const struct isa_ext_data isa_edata_arr[] = {
     ISA_EXT_DATA_ENTRY(h, false, PRIV_VERSION_1_12_0, ext_h),
     ISA_EXT_DATA_ENTRY(v, false, PRIV_VERSION_1_12_0, ext_v),
+    ISA_EXT_DATA_ENTRY(zicond, true, PRIV_VERSION_1_12_0, ext_zicond),
     ISA_EXT_DATA_ENTRY(zicsr, true, PRIV_VERSION_1_10_0, ext_icsr),
     ISA_EXT_DATA_ENTRY(zifencei, true, PRIV_VERSION_1_10_0, ext_ifencei),
     ISA_EXT_DATA_ENTRY(zihintpause, true, PRIV_VERSION_1_10_0, ext_zihintpause),
@@ -1080,6 +1081,9 @@  static Property riscv_cpu_extensions[] = {
     DEFINE_PROP_BOOL("x-smaia", RISCVCPU, cfg.ext_smaia, false),
     DEFINE_PROP_BOOL("x-ssaia", RISCVCPU, cfg.ext_ssaia, false),
 
+    /* Zicond 1.0-draft-20230120 */
+    DEFINE_PROP_BOOL("x-zicond", RISCVCPU, cfg.ext_zicond, false),
+
     DEFINE_PROP_END_OF_LIST(),
 };
 
diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
index f5609b62a2..4b6ff800d3 100644
--- a/target/riscv/cpu.h
+++ b/target/riscv/cpu.h
@@ -446,6 +446,7 @@  struct RISCVCPUConfig {
     bool ext_zkt;
     bool ext_ifencei;
     bool ext_icsr;
+    bool ext_zicond;
     bool ext_zihintpause;
     bool ext_smstateen;
     bool ext_sstc;
diff --git a/target/riscv/insn32.decode b/target/riscv/insn32.decode
index b7e7613ea2..ca812c2f7a 100644
--- a/target/riscv/insn32.decode
+++ b/target/riscv/insn32.decode
@@ -890,3 +890,7 @@  sm3p1       00 01000 01001 ..... 001 ..... 0010011 @r2
 # *** RV32 Zksed Standard Extension ***
 sm4ed       .. 11000 ..... ..... 000 ..... 0110011 @k_aes
 sm4ks       .. 11010 ..... ..... 000 ..... 0110011 @k_aes
+
+# *** Zicond Standard Extension ***
+czero_eqz   0000111 ..... ..... 101 ..... 0110011 @r
+czero_nez   0000111 ..... ..... 111 ..... 0110011 @r
diff --git a/target/riscv/insn_trans/trans_rvzicond.c.inc b/target/riscv/insn_trans/trans_rvzicond.c.inc
new file mode 100644
index 0000000000..20e9694a2c
--- /dev/null
+++ b/target/riscv/insn_trans/trans_rvzicond.c.inc
@@ -0,0 +1,54 @@ 
+/*
+ * RISC-V translation routines for the XVentanaCondOps extension.
+ *
+ * Copyright (c) 2022 VRULL GmbH.
+ *
+ * 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_ZICOND(ctx) do {                 \
+    if (!ctx->cfg_ptr->ext_zicond) {             \
+        return false;                            \
+    }                                            \
+} while (0)
+
+/* Emits "$rd = ($rs2 <cond> $zero) ? $zero : $rs1" */
+static inline void gen_czero(TCGv dest, TCGv src1, TCGv src2, TCGCond cond)
+{
+    TCGv zero = tcg_constant_tl(0);
+    tcg_gen_movcond_tl(cond, dest, src2, zero, zero, src1);
+}
+
+static inline void gen_czero_eqz(TCGv dest, TCGv src1, TCGv src2)
+{
+    gen_czero(dest, src1, src2, TCG_COND_EQ);
+}
+
+static inline void gen_czero_nez(TCGv dest, TCGv src1, TCGv src2)
+{
+    gen_czero(dest, src1, src2, TCG_COND_NE);
+}
+
+static bool trans_czero_eqz(DisasContext *ctx, arg_r *a)
+{
+    REQUIRE_ZICOND(ctx);
+
+    return gen_logic(ctx, a, gen_czero_eqz);
+}
+
+static bool trans_czero_nez(DisasContext *ctx, arg_r *a)
+{
+    REQUIRE_ZICOND(ctx);
+
+    return gen_logic(ctx, a, gen_czero_nez);
+}
diff --git a/target/riscv/translate.c b/target/riscv/translate.c
index df38db7553..1468748835 100644
--- a/target/riscv/translate.c
+++ b/target/riscv/translate.c
@@ -1061,6 +1061,7 @@  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_rvzawrs.c.inc"
+#include "insn_trans/trans_rvzicond.c.inc"
 #include "insn_trans/trans_rvzfh.c.inc"
 #include "insn_trans/trans_rvk.c.inc"
 #include "insn_trans/trans_privileged.c.inc"