RE: [PATCH v2 3/9] Hexagon (target/hexagon) Mark dest_idx in trans functions

[Brian Cain]

> -----Original Message-----
> From: Taylor Simpson <ltaylorsimpson@gmail.com>
> Sent: Wednesday, March 6, 2024 9:23 PM
> To: qemu-devel@nongnu.org
> Cc: Brian Cain <bcain@quicinc.com>; Matheus Bernardino (QUIC)
> <quic_mathbern@quicinc.com>; Sid Manning <sidneym@quicinc.com>;
> Marco Liebel (QUIC) <quic_mliebel@quicinc.com>;
> richard.henderson@linaro.org; philmd@linaro.org; ale@rev.ng; anjo@rev.ng;
> ltaylorsimpson@gmail.com
> Subject: [PATCH v2 3/9] Hexagon (target/hexagon) Mark dest_idx in trans
> functions
> 
> WARNING: This email originated from outside of Qualcomm. Please be wary
> of any links or attachments, and do not enable macros.
> 
> Check that the value matches opcode_reginfo/opcode_wregs
> 
> Signed-off-by: Taylor Simpson <ltaylorsimpson@gmail.com>
> ---

Reviewed-by: Brian Cain <bcain@quicinc.com>

>  target/hexagon/insn.h                   | 1 +
>  target/hexagon/decode.c                 | 2 ++
>  target/hexagon/mmvec/decode_ext_mmvec.c | 2 ++
>  target/hexagon/gen_trans_funcs.py       | 6 ++++++
>  4 files changed, 11 insertions(+)
> 
> diff --git a/target/hexagon/insn.h b/target/hexagon/insn.h
> index 36502bf056..a770379958 100644
> --- a/target/hexagon/insn.h
> +++ b/target/hexagon/insn.h
> @@ -40,6 +40,7 @@ struct Instruction {
>      uint32_t which_extended:1;    /* If has an extender, which immediate */
>      uint32_t new_value_producer_slot:4;
>      int32_t new_read_idx;
> +    int32_t dest_idx;
> 
>      bool part1;              /*
>                                * cmp-jumps are split into two insns.
> diff --git a/target/hexagon/decode.c b/target/hexagon/decode.c
> index 4595e30384..a4d8500fea 100644
> --- a/target/hexagon/decode.c
> +++ b/target/hexagon/decode.c
> @@ -184,6 +184,8 @@ decode_fill_newvalue_regno(Packet *packet)
> 
>              /* Now patch up the consumer with the register number */
>              dst_idx = dststr - opcode_reginfo[def_opcode];
> +            g_assert(packet->insn[def_idx].dest_idx != -1 &&
> +                     packet->insn[def_idx].dest_idx == dst_idx);
>              packet->insn[i].regno[use_regidx] =
>                  packet->insn[def_idx].regno[dst_idx];
>              /*
> diff --git a/target/hexagon/mmvec/decode_ext_mmvec.c
> b/target/hexagon/mmvec/decode_ext_mmvec.c
> index e9007f5d71..c1320406df 100644
> --- a/target/hexagon/mmvec/decode_ext_mmvec.c
> +++ b/target/hexagon/mmvec/decode_ext_mmvec.c
> @@ -86,6 +86,8 @@ check_new_value(Packet *pkt)
>                      /* still not there, we have a bad packet */
>                      g_assert_not_reached();
>                  }
> +                g_assert(pkt->insn[def_idx].dest_idx != -1 &&
> +                         pkt->insn[def_idx].dest_idx == dststr - reginfo);
>                  int def_regnum = pkt->insn[def_idx].regno[dststr - reginfo];
>                  /* Now patch up the consumer with the register number */
>                  pkt->insn[i].regno[use_regidx] = def_regnum ^ def_oreg;
> diff --git a/target/hexagon/gen_trans_funcs.py
> b/target/hexagon/gen_trans_funcs.py
> index 8acecdb993..1201172dda 100755
> --- a/target/hexagon/gen_trans_funcs.py
> +++ b/target/hexagon/gen_trans_funcs.py
> @@ -69,6 +69,7 @@ def mark_which_imm_extended(f, tag):
>  ##         insn->regno[1] = args->Rs;
>  ##         insn->regno[2] = args->Rt;
>  ##         insn->new_read_idx = -1;
> +##         insn->dest_idx = 0;
>  ##         return true;
>  ##     }
>  ##
> @@ -86,6 +87,7 @@ def gen_trans_funcs(f):
>          """))
> 
>          new_read_idx = -1
> +        dest_idx = -1
>          for regno, (reg_type, reg_id, *_) in enumerate(regs):
>              reg = hex_common.get_register(tag, reg_type, reg_id)
>              f.write(code_fmt(f"""\
> @@ -93,6 +95,9 @@ def gen_trans_funcs(f):
>              """))
>              if reg.is_read() and reg.is_new():
>                  new_read_idx = regno
> +            # dest_idx should be the first destination, so check for -1
> +            if reg.is_written() and dest_idx == -1:
> +                dest_idx = regno
> 
>          if len(imms) != 0:
>              mark_which_imm_extended(f, tag)
> @@ -115,6 +120,7 @@ def gen_trans_funcs(f):
> 
>          f.write(code_fmt(f"""\
>              insn->new_read_idx = {new_read_idx};
> +            insn->dest_idx = {dest_idx};
>          """))
>          f.write(textwrap.dedent(f"""\
>                  return true;
> --
> 2.34.1