Re: [PATCH v3 4/6] target/riscv: zfh: half-precision floating-point compare

[Alistair Francis]

On Sat, Oct 16, 2021 at 7:12 PM <frank.chang@sifive.com> wrote:
>
> From: Kito Cheng <kito.cheng@sifive.com>
>
> Signed-off-by: Kito Cheng <kito.cheng@sifive.com>
> Signed-off-by: Chih-Min Chao <chihmin.chao@sifive.com>
> Signed-off-by: Frank Chang <frank.chang@sifive.com>
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

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

Alistair

> ---
>  target/riscv/fpu_helper.c                 | 21 +++++++++++++
>  target/riscv/helper.h                     |  3 ++
>  target/riscv/insn32.decode                |  3 ++
>  target/riscv/insn_trans/trans_rvzfh.c.inc | 37 +++++++++++++++++++++++
>  4 files changed, 64 insertions(+)
>
> diff --git a/target/riscv/fpu_helper.c b/target/riscv/fpu_helper.c
> index 2ed9b03193c..ec2009ee65b 100644
> --- a/target/riscv/fpu_helper.c
> +++ b/target/riscv/fpu_helper.c
> @@ -461,6 +461,27 @@ uint64_t helper_fsqrt_h(CPURISCVState *env, uint64_t rs1)
>      return nanbox_h(float16_sqrt(frs1, &env->fp_status));
>  }
>
> +target_ulong helper_fle_h(CPURISCVState *env, uint64_t rs1, uint64_t rs2)
> +{
> +    float16 frs1 = check_nanbox_h(rs1);
> +    float16 frs2 = check_nanbox_h(rs2);
> +    return float16_le(frs1, frs2, &env->fp_status);
> +}
> +
> +target_ulong helper_flt_h(CPURISCVState *env, uint64_t rs1, uint64_t rs2)
> +{
> +    float16 frs1 = check_nanbox_h(rs1);
> +    float16 frs2 = check_nanbox_h(rs2);
> +    return float16_lt(frs1, frs2, &env->fp_status);
> +}
> +
> +target_ulong helper_feq_h(CPURISCVState *env, uint64_t rs1, uint64_t rs2)
> +{
> +    float16 frs1 = check_nanbox_h(rs1);
> +    float16 frs2 = check_nanbox_h(rs2);
> +    return float16_eq_quiet(frs1, frs2, &env->fp_status);
> +}
> +
>  target_ulong helper_fcvt_w_h(CPURISCVState *env, uint64_t rs1)
>  {
>      float16 frs1 = check_nanbox_h(rs1);
> diff --git a/target/riscv/helper.h b/target/riscv/helper.h
> index b50672d1684..9c89521d4ad 100644
> --- a/target/riscv/helper.h
> +++ b/target/riscv/helper.h
> @@ -74,6 +74,9 @@ DEF_HELPER_FLAGS_3(fdiv_h, TCG_CALL_NO_RWG, i64, env, i64, 
> i64)
>  DEF_HELPER_FLAGS_3(fmin_h, TCG_CALL_NO_RWG, i64, env, i64, i64)
>  DEF_HELPER_FLAGS_3(fmax_h, TCG_CALL_NO_RWG, i64, env, i64, i64)
>  DEF_HELPER_FLAGS_2(fsqrt_h, TCG_CALL_NO_RWG, i64, env, i64)
> +DEF_HELPER_FLAGS_3(fle_h, TCG_CALL_NO_RWG, tl, env, i64, i64)
> +DEF_HELPER_FLAGS_3(flt_h, TCG_CALL_NO_RWG, tl, env, i64, i64)
> +DEF_HELPER_FLAGS_3(feq_h, TCG_CALL_NO_RWG, tl, env, i64, i64)
>  DEF_HELPER_FLAGS_2(fcvt_s_h, TCG_CALL_NO_RWG, i64, env, i64)
>  DEF_HELPER_FLAGS_2(fcvt_h_s, TCG_CALL_NO_RWG, i64, env, i64)
>  DEF_HELPER_FLAGS_2(fcvt_d_h, TCG_CALL_NO_RWG, i64, env, i64)
> diff --git a/target/riscv/insn32.decode b/target/riscv/insn32.decode
> index ba40f3e7f89..3906c9fb201 100644
> --- a/target/riscv/insn32.decode
> +++ b/target/riscv/insn32.decode
> @@ -751,6 +751,9 @@ fcvt_d_h   0100001  00010 ..... ... ..... 1010011 @r2_rm
>  fcvt_w_h   1100010  00000 ..... ... ..... 1010011 @r2_rm
>  fcvt_wu_h  1100010  00001 ..... ... ..... 1010011 @r2_rm
>  fmv_x_h    1110010  00000 ..... 000 ..... 1010011 @r2
> +feq_h      1010010  ..... ..... 010 ..... 1010011 @r
> +flt_h      1010010  ..... ..... 001 ..... 1010011 @r
> +fle_h      1010010  ..... ..... 000 ..... 1010011 @r
>  fcvt_h_w   1101010  00000 ..... ... ..... 1010011 @r2_rm
>  fcvt_h_wu  1101010  00001 ..... ... ..... 1010011 @r2_rm
>  fmv_h_x    1111010  00000 ..... 000 ..... 1010011 @r2
> diff --git a/target/riscv/insn_trans/trans_rvzfh.c.inc 
> b/target/riscv/insn_trans/trans_rvzfh.c.inc
> index d1250257666..8d0959a6671 100644
> --- a/target/riscv/insn_trans/trans_rvzfh.c.inc
> +++ b/target/riscv/insn_trans/trans_rvzfh.c.inc
> @@ -335,6 +335,43 @@ static bool trans_fcvt_h_d(DisasContext *ctx, 
> arg_fcvt_h_d *a)
>      return true;
>  }
>
> +static bool trans_feq_h(DisasContext *ctx, arg_feq_h *a)
> +{
> +    REQUIRE_FPU;
> +    REQUIRE_ZFH(ctx);
> +
> +    TCGv dest = dest_gpr(ctx, a->rd);
> +
> +    gen_helper_feq_h(dest, cpu_env, cpu_fpr[a->rs1], cpu_fpr[a->rs2]);
> +    gen_set_gpr(ctx, a->rd, dest);
> +    return true;
> +}
> +
> +static bool trans_flt_h(DisasContext *ctx, arg_flt_h *a)
> +{
> +    REQUIRE_FPU;
> +    REQUIRE_ZFH(ctx);
> +
> +    TCGv dest = dest_gpr(ctx, a->rd);
> +
> +    gen_helper_flt_h(dest, cpu_env, cpu_fpr[a->rs1], cpu_fpr[a->rs2]);
> +    gen_set_gpr(ctx, a->rd, dest);
> +
> +    return true;
> +}
> +
> +static bool trans_fle_h(DisasContext *ctx, arg_fle_h *a)
> +{
> +    REQUIRE_FPU;
> +    REQUIRE_ZFH(ctx);
> +
> +    TCGv dest = dest_gpr(ctx, a->rd);
> +
> +    gen_helper_fle_h(dest, cpu_env, cpu_fpr[a->rs1], cpu_fpr[a->rs2]);
> +    gen_set_gpr(ctx, a->rd, dest);
> +    return true;
> +}
> +
>  static bool trans_fcvt_w_h(DisasContext *ctx, arg_fcvt_w_h *a)
>  {
>      REQUIRE_FPU;
> --
> 2.25.1
>
>