[dataflow]: PATCH: fix a fortran regression on x86-64, and compiler ICE on ia64

[Kenneth Zadeck]

Seongbae Park wrote:
> This patch fixes the remaining fortran regression on x86-6
> which was due to missing modeling of the static chain register
> in the entry block.
> Also, it has a fix for one compiler segmentation faulting problem on ia64
> in if conversion.
> Bootstrap and tested on x86-64.
> On IA64, bootstraped with c/c++ only.
>
> Seongbae
>
>
> 2006-11-15  Seongbae Park <seongbae.park@gmail.com>
>
>        * df-scan.c (df_insn_refs_collect): Code cleanup
>        for COND_EXEC handling.
>        (df_need_static_chain_reg): New function.
>        (df_get_entry_block_def_set): Check and add the static chain
> register.
>        * ifcvt.c (if_convert): Don't ignore the return value
>        of find_if_header.
> ------------------------------------------------------------------------
>
> Index: gcc/df-scan.c
> ===================================================================
> --- gcc/df-scan.c	(revision 118871)
> +++ gcc/df-scan.c	(working copy)
> @@ -2022,8 +2022,8 @@ df_insn_refs_collect (struct dataflow *d
>  {
>    struct df_ref dummy;
>    struct df_ref *insn_refs = &dummy;
> -  struct df_ref *cond_uses;
>    rtx note;
> +  bool is_cond_exec = (GET_CODE (PATTERN (insn)) == COND_EXEC);
>  
>    DF_REF_NEXT_REF (insn_refs) = NULL;
>    
> @@ -2047,24 +2047,24 @@ df_insn_refs_collect (struct dataflow *d
>      }
>  
>    if (CALL_P (insn))
> -    {
> -       enum df_ref_flags extra_flags = (GET_CODE (PATTERN (insn)) == COND_EXEC) 
> -                                ? DF_REF_CONDITIONAL : 0;
> -       insn_refs = df_get_call_refs (dflow, insn_refs, bb, insn, extra_flags);
> -    }
> +    insn_refs = df_get_call_refs (dflow, insn_refs, bb, insn, 
> +                                  (is_cond_exec) ? DF_REF_CONDITIONAL : 0);
>  
>    /* Record the register uses.  */
>    insn_refs = df_uses_record (dflow, insn_refs,
>                                &PATTERN (insn), DF_REF_REG_USE, bb, insn, 0);
>  
>    /* DF_REF_CONDITIONAL needs corresponding USES. */
> -  cond_uses = df_get_conditional_uses (dflow, DF_REF_NEXT_REF (&dummy));
> -
> -  if (cond_uses) 
> +  if (is_cond_exec)
>      {
> -      DF_REF_NEXT_REF (insn_refs) = DF_REF_NEXT_REF (cond_uses);
> -      DF_REF_NEXT_REF (cond_uses) = NULL;
> -      insn_refs = cond_uses;
> +      struct df_ref *cond_uses;
> +      cond_uses = df_get_conditional_uses (dflow, DF_REF_NEXT_REF (&dummy));
> +      if (cond_uses) 
> +	{
> +	  DF_REF_NEXT_REF (insn_refs) = DF_REF_NEXT_REF (cond_uses);
> +	  DF_REF_NEXT_REF (cond_uses) = NULL;
> +	  insn_refs = cond_uses;
> +	}
>      }
>  
>    return DF_REF_NEXT_REF (&dummy);
> @@ -2155,6 +2155,18 @@ df_recompute_luids (struct df *df, basic
>  }
>  
>  
> +/* Returns true if the function entry needs to 
> +   define the static chain register.  */
> +
> +static bool
> +df_need_static_chain_reg (struct function *fun)
> +{
> +  tree fun_context = decl_function_context (fun->decl);
> +  return fun_context
> +         && DECL_NO_STATIC_CHAIN (fun_context) == false;
> +}
> +
> +
>  /* Set the bit for regs that are considered being defined at the entry. */
>  
>  static void
> @@ -2253,6 +2265,18 @@ df_get_entry_block_def_set (bitmap entry
>      }
>  
>    targetm.live_on_entry (entry_block_defs);
> +
> +  /* If the function has an incoming STATIC_CHAIN,
> +     it has to show up in the entry def set.  */
> +  if (df_need_static_chain_reg (cfun))
> +    {
> +#if !defined (STATIC_CHAIN_INCOMING_REGNUM) \
> +      || STATIC_CHAIN_REGNUM == STATIC_CHAIN_INCOMING_REGNUM
> +      bitmap_set_bit (entry_block_defs, STATIC_CHAIN_REGNUM);
> +#else 
> +      bitmap_set_bit (entry_block_defs, STATIC_CHAIN_INCOMING_REGNUM);
> +#endif
> +    }
>  }
>  
>  
> @@ -2688,7 +2712,7 @@ df_get_exit_block_use_set (bitmap exit_b
>  	df_mark_reg (tmp, exit_block_uses);
>      }
>  #endif 
> -  
> +
>    /* Mark function return value.  */
>    diddle_return_value (df_mark_reg, (void*) exit_block_uses);
>  }
> Index: gcc/ifcvt.c
> ===================================================================
> --- gcc/ifcvt.c	(revision 118871)
> +++ gcc/ifcvt.c	(working copy)
> @@ -3899,9 +3899,10 @@ if_convert (void)
>  
>        FOR_EACH_BB (bb)
>  	{
> -	  
> -	  if (!df_get_bb_dirty (bb))
> -	    find_if_header (df, bb, pass);
> +          basic_block new_bb;
> +          while (!df_get_bb_dirty (bb) 
> +                 && (new_bb = find_if_header (df, bb, pass)) != NULL)
> +            bb = new_bb;
>  	}
>  
>  #ifdef IFCVT_MULTIPLE_DUMPS
>   
ok to commit.
kenny