Re: [PATCH 1/4] target/riscv: Add zimop extension

[LIU Zhiwei <zhiwei_liu@linux.alibaba.com>]

Hi Daniel,

On 2024/5/24 17:46, Daniel Henrique Barboza wrote:
>
>
> On 5/22/24 03:29, LIU Zhiwei wrote:
>> Zimop extension defines an encoding space for 40 MOPs.The Zimop
>> extension defines 32 MOP instructions named MOP.R.n, where n is
>> an integer between 0 and 31, inclusive. The Zimop extension
>> additionally defines 8 MOP instructions named MOP.RR.n, where n
>> is an integer between 0 and 7.
>>
>> These 40 MOPs initially are defined to simply write zero to x[rd],
>> but are designed to be redefined by later extensions to perform some
>> other action.
>>
>> Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
>> ---
>>   target/riscv/cpu.c                          |  2 ++
>>   target/riscv/cpu_cfg.h                      |  1 +
>>   target/riscv/insn32.decode                  | 11 ++++++
>>   target/riscv/insn_trans/trans_rvzimop.c.inc | 37 +++++++++++++++++++++
>>   target/riscv/translate.c                    |  1 +
>>   5 files changed, 52 insertions(+)
>>   create mode 100644 target/riscv/insn_trans/trans_rvzimop.c.inc
>>
>> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
>> index eb1a2e7d6d..c1ac521142 100644
>> --- a/target/riscv/cpu.c
>> +++ b/target/riscv/cpu.c
>> @@ -175,6 +175,7 @@ const RISCVIsaExtData isa_edata_arr[] = {
>>       ISA_EXT_DATA_ENTRY(zvkt, PRIV_VERSION_1_12_0, ext_zvkt),
>>       ISA_EXT_DATA_ENTRY(zhinx, PRIV_VERSION_1_12_0, ext_zhinx),
>>       ISA_EXT_DATA_ENTRY(zhinxmin, PRIV_VERSION_1_12_0, ext_zhinxmin),
>> +    ISA_EXT_DATA_ENTRY(zimop, PRIV_VERSION_1_12_0, ext_zimop),
>
> Shouldn't this be placed right after zihpm?

Yes. Thanks.

I didn't notice the strict order between extensions. And will fix this 
and other similar comments in other patches.

Zhiwei

>
>     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(zimop, PRIV_VERSION_1_12_0, ext_zimop),
>     ISA_EXT_DATA_ENTRY(zmmul, PRIV_VERSION_1_12_0, ext_zmmul),
>
>
> Thanks,
>
> Daniel
>
>
>>       ISA_EXT_DATA_ENTRY(smaia, PRIV_VERSION_1_12_0, ext_smaia),
>>       ISA_EXT_DATA_ENTRY(smepmp, PRIV_VERSION_1_12_0, ext_smepmp),
>>       ISA_EXT_DATA_ENTRY(smstateen, PRIV_VERSION_1_12_0, ext_smstateen),
>> @@ -1463,6 +1464,7 @@ 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("zimop", ext_zimop, 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 cb750154bd..b547fbba9d 100644
>> --- a/target/riscv/cpu_cfg.h
>> +++ b/target/riscv/cpu_cfg.h
>> @@ -71,6 +71,7 @@ struct RISCVCPUConfig {
>>       bool ext_zihintntl;
>>       bool ext_zihintpause;
>>       bool ext_zihpm;
>> +    bool ext_zimop;
>>       bool ext_ztso;
>>       bool ext_smstateen;
>>       bool ext_sstc;
>> diff --git a/target/riscv/insn32.decode b/target/riscv/insn32.decode
>> index f22df04cfd..972a1e8fd1 100644
>> --- a/target/riscv/insn32.decode
>> +++ b/target/riscv/insn32.decode
>> @@ -38,6 +38,8 @@
>>   %imm_bs   30:2                   !function=ex_shift_3
>>   %imm_rnum 20:4
>>   %imm_z6   26:1 15:5
>> +%imm_mop5 30:1 26:2 20:2
>> +%imm_mop3 30:1 26:2
>>     # Argument sets:
>>   &empty
>> @@ -56,6 +58,8 @@
>>   &r2nfvm    vm rd rs1 nf
>>   &rnfvm     vm rd rs1 rs2 nf
>>   &k_aes     shamt rs2 rs1 rd
>> +&mop5 imm rd rs1
>> +&mop3 imm rd rs1 rs2
>>     # Formats 32:
>>   @r       .......   ..... ..... ... ..... ....... &r                
>> %rs2 %rs1 %rd
>> @@ -98,6 +102,9 @@
>>   @k_aes   .. ..... ..... .....  ... ..... ....... &k_aes 
>> shamt=%imm_bs   %rs2 %rs1 %rd
>>   @i_aes   .. ..... ..... .....  ... ..... ....... &i 
>> imm=%imm_rnum        %rs1 %rd
>>   +@mop5 . . .. .. .... .. ..... ... ..... ....... &mop5 
>> imm=%imm_mop5 %rd %rs1
>> +@mop3 . . .. .. . ..... ..... ... ..... ....... &mop3 imm=%imm_mop3 
>> %rd %rs1 %rs2
>> +
>>   # Formats 64:
>>   @sh5     .......  ..... .....  ... ..... ....... &shift 
>> shamt=%sh5      %rs1 %rd
>>   @@ -1010,3 +1017,7 @@ 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
>> +
>> +# *** Zimop may-be-operation extension ***
>> +mop_r_n     1 . 00 .. 0111 .. ..... 100 ..... 0111011 @mop5
>> +mop_rr_n    1 . 00 .. 1 ..... ..... 100 ..... 0111011 @mop3
>> diff --git a/target/riscv/insn_trans/trans_rvzimop.c.inc 
>> b/target/riscv/insn_trans/trans_rvzimop.c.inc
>> new file mode 100644
>> index 0000000000..165aacd2b6
>> --- /dev/null
>> +++ b/target/riscv/insn_trans/trans_rvzimop.c.inc
>> @@ -0,0 +1,37 @@
>> +/*
>> + * RISC-V translation routines for May-Be-Operation(zimop).
>> + *
>> + * 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_ZIMOP(ctx) do {           \
>> +    if (!ctx->cfg_ptr->ext_zimop) {       \
>> +        return false;                     \
>> +    }                                     \
>> +} while (0)
>> +
>> +static bool trans_mop_r_n(DisasContext *ctx, arg_mop_r_n *a)
>> +{
>> +    REQUIRE_ZIMOP(ctx);
>> +    gen_set_gpr(ctx, a->rd, ctx->zero);
>> +    return true;
>> +}
>> +
>> +static bool trans_mop_rr_n(DisasContext *ctx, arg_mop_rr_n *a)
>> +{
>> +    REQUIRE_ZIMOP(ctx);
>> +    gen_set_gpr(ctx, a->rd, ctx->zero);
>> +    return true;
>> +}
>> diff --git a/target/riscv/translate.c b/target/riscv/translate.c
>> index 2c27fd4ce1..77c6564834 100644
>> --- a/target/riscv/translate.c
>> +++ b/target/riscv/translate.c
>> @@ -1097,6 +1097,7 @@ static uint32_t opcode_at(DisasContextBase 
>> *dcbase, target_ulong pc)
>>   #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_rvzimop.c.inc"
>>   #include "insn_trans/trans_rvzfa.c.inc"
>>   #include "insn_trans/trans_rvzfh.c.inc"
>>   #include "insn_trans/trans_rvk.c.inc"