Re: Fwd: [PATCH] Scheduling result adjustment to enable macro-fusion

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Tue, Sep 24, 2013 at 12:06 PM, Wei Mi <wmi@google.com> wrote:
> This is the updated patch2.
> Changed:
> 1. For cmp/test with rip-relative addressing mem operand, don't group
> insns. Bulldozer also doesn't support fusion for cmp/test with both
> displacement MEM and immediate operand, while m_CORE_ALL doesn't
> support fusion for cmp/test with MEM and immediate operand. I simplify
> choose to use the more stringent constraint here (m_CORE_ALL's
> constraint).
> 2. Add Budozer back and merge TARGET_FUSE_CMP_AND_BRANCH_64 and
> TARGET_FUSE_CMP_AND_BRANCH_32.
>
> bootstrap and regression pass. ok for trunk?
>
> 2013-09-24  Wei Mi  <wmi@google.com>
>
>         * gcc/config/i386/i386.c (rip_relative_addr_p): New Function.
>         (ix86_macro_fusion_p): Ditto.
>         (ix86_macro_fusion_pair_p): Ditto.
>         * gcc/config/i386/i386.h: Add new tune features about macro-fusion.
>         * gcc/config/i386/x86-tune.def (DEF_TUNE): Ditto.
>         * gcc/doc/tm.texi: Generated.
>         * gcc/doc/tm.texi.in: Ditto.
>         * gcc/haifa-sched.c (try_group_insn): New Function.
>         (group_insns_for_macro_fusion): Ditto.
>         (sched_init): Call group_insns_for_macro_fusion.
>         * gcc/sched-rgn.c (add_branch_dependences): Keep insns in
>         a SCHED_GROUP at the end of BB to remain their location.
>         * gcc/target.def: Add two hooks: macro_fusion_p and
>         macro_fusion_pair_p.
>
> diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
> index 1fd3f60..4a04778 100644
> --- a/gcc/config/i386/i386.c
> +++ b/gcc/config/i386/i386.c
> @@ -24856,6 +24856,167 @@ ia32_multipass_dfa_lookahead (void)
>      }
>  }
>
> +/* Extracted from ix86_print_operand_address. Check whether ADDR is a
> +   rip-relative address.  */
> +
> +static bool
> +rip_relative_addr_p (rtx addr)
> +{
> +  struct ix86_address parts;
> +  rtx base, index, disp;
> +  int ok;
> +
> +  if (GET_CODE (addr) == UNSPEC && XINT (addr, 1) == UNSPEC_VSIBADDR)
> +    {
> +      ok = ix86_decompose_address (XVECEXP (addr, 0, 0), &parts);
> +      parts.index = XVECEXP (addr, 0, 1);
> +    }
> +  else if (GET_CODE (addr) == UNSPEC && XINT (addr, 1) == UNSPEC_LEA_ADDR)
> +    ok = ix86_decompose_address (XVECEXP (addr, 0, 0), &parts);
> +  else
> +    ok = ix86_decompose_address (addr, &parts);
> +
> +  gcc_assert (ok);
> +  base = parts.base;
> +  index = parts.index;
> +  disp = parts.disp;
> +
> +  if (TARGET_64BIT && !base && !index)
> +    {
> +      rtx symbol = disp;
> +
> +      if (GET_CODE (disp) == CONST
> +         && GET_CODE (XEXP (disp, 0)) == PLUS
> +         && CONST_INT_P (XEXP (XEXP (disp, 0), 1)))
> +       symbol = XEXP (XEXP (disp, 0), 0);
> +
> +      if (GET_CODE (symbol) == LABEL_REF
> +         || (GET_CODE (symbol) == SYMBOL_REF
> +             && SYMBOL_REF_TLS_MODEL (symbol) == 0))
> +       return true;
> +    }
> +  if (flag_pic && !base && !index)
> +    {
> +      if (GET_CODE (disp) == CONST
> +         && GET_CODE (XEXP (disp, 0)) == UNSPEC
> +         && (XINT (XEXP (disp, 0), 1) == UNSPEC_PCREL
> +             || XINT (XEXP (disp, 0), 1) == UNSPEC_GOTPCREL
> +             || (TARGET_64BIT
> +                 && XINT (XEXP (disp, 0), 1) == UNSPEC_GOTNTPOFF)))
> +       return true;
> +    }
> +  return false;
> +}
> +

It doesn't look right.  IP relative address is only possible
with TARGET_64BIT and

1. base == pc. Or
2. UUNSPEC_PCREL,  UNSPEC_GOTPCREL, and
NSPEC_GOTNTPOFF.


-- 
H.J.