Re: [patch v2] Get rid of stack trampolines for nested functions (1/4)

[Andreas Schwab <schwab@suse.de>]

On Sep 04 2016, Eric Botcazou <ebotcazou@adacore.com> wrote:

> Index: calls.c
> ===================================================================
> --- calls.c	(revision 239944)
> +++ calls.c	(working copy)
> @@ -183,17 +183,76 @@ static void restore_fixed_argument_area (rtx, rtx,
>  
>  rtx
>  prepare_call_address (tree fndecl_or_type, rtx funexp, rtx static_chain_value,
> -		      rtx *call_fusage, int reg_parm_seen, int sibcallp)
> +		      rtx *call_fusage, int reg_parm_seen, int flags)
>  {
>    /* Make a valid memory address and copy constants through pseudo-regs,
>       but not for a constant address if -fno-function-cse.  */
>    if (GET_CODE (funexp) != SYMBOL_REF)
> -    /* If we are using registers for parameters, force the
> -       function address into a register now.  */
> -    funexp = ((reg_parm_seen
> -	       && targetm.small_register_classes_for_mode_p (FUNCTION_MODE))
> -	      ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
> -	      : memory_address (FUNCTION_MODE, funexp));
> +    {
> +      /* If it's an indirect call by descriptor, generate code to perform
> +	 runtime identification of the pointer and load the descriptor.  */
> +      if ((flags & ECF_BY_DESCRIPTOR) && !flag_trampolines)
> +	{
> +	  const int bit_val = targetm.calls.custom_function_descriptors;
> +	  rtx call_lab = gen_label_rtx ();
> +
> +	  gcc_assert (fndecl_or_type && TYPE_P (fndecl_or_type));
> +	  fndecl_or_type
> +	    = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL, NULL_TREE,
> +			  fndecl_or_type);
> +	  DECL_STATIC_CHAIN (fndecl_or_type) = 1;
> +	  rtx chain = targetm.calls.static_chain (fndecl_or_type, false);
> +
> +	  /* Avoid long live ranges around function calls.  */
> +	  funexp = copy_to_mode_reg (Pmode, funexp);

That needs to use ptr_mode, not Pmode.

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
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