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From: Christian Bruel <christian.bruel@st.com>
To: ramana Radhakrishnan <Ramana.Radhakrishnan@arm.com>,
	       Richard Biener <rguenther@suse.de>
Cc: <gcc-patches@gcc.gnu.org>
Subject: Re: [PATCH] Fix inlining checks wrt optimize attribute
Date: Thu, 22 Jan 2015 10:36:00 -0000	[thread overview]
Message-ID: <54C0CF92.6080001@st.com> (raw)
In-Reply-To: <alpine.LSU.2.11.1501221023100.12482@zhemvz.fhfr.qr>

Hi Richard,

I thought one of my current issue would be solved by this patch, but it 
is not : I have some inlining failures with the attribute target on ARM. 
(e.g inline-3.c) where obvious early inline fails with because we fail 
into the last can_inline_edge_p case:

opt_for_fn (callee->decl, optimize)
		   >= opt_for_fn (caller->decl, optimize)))

when callee and caller are both -O2 and 
targetm.target_option.can_inline_p was true, they should be inlined as 
in the general case (no DECL_FUNCTION_SPECIFIC_OPTIMIZATION)

I'm currently testing this additional change:

Index: ipa-inline.c
===================================================================
--- ipa-inline.c	(revision 219989)
+++ ipa-inline.c	(working copy)
@@ -489,7 +489,7 @@
        else if (opt_for_fn (callee->decl, optimize_size)
  	       < opt_for_fn (caller->decl, optimize_size)
  	       || (opt_for_fn (callee->decl, optimize)
-		   >= opt_for_fn (caller->decl, optimize)))
+		   > opt_for_fn (caller->decl, optimize)))
  	{
  	  if (estimate_edge_time (e)
  	      >= 20 + inline_edge_summary (e)->call_stmt_time)

Since this is a hot topic for you, I though you would have useful 
comments on this before I ask for a commit (when stage 4 close) ?

Cheers

Christian





On 01/22/2015 10:24 AM, Richard Biener wrote:
>
> As said in the other thread - this makes sure we don't perform inlining
> that might end up generating invalid code.  It also preserves
> user-provided optimize attributes more properly.
>
> Bootstrapped and tested on x86_64-unknown-linux-gnu, applied to trunk.
>
> Richard.
>
> 2015-01-22  Richard Biener  <rguenther@suse.de>
>
> 	* ipa-inline.c (can_inline_edge_p): Disable inlining of edges
> 	with IL incompatible options.  Properly honor user optimize
> 	attributes.
>
> Index: gcc/ipa-inline.c
> ===================================================================
> --- gcc/ipa-inline.c	(revision 219929)
> +++ gcc/ipa-inline.c	(working copy)
> @@ -404,17 +404,56 @@ can_inline_edge_p (struct cgraph_edge *e
>        optimization attribute.  */
>     else if (caller_tree != callee_tree)
>       {
> -      /* gcc.dg/pr43564.c.  Look at forced inline even in -O0.  */
> -      if (DECL_DISREGARD_INLINE_LIMITS (callee->decl))
> +      /* There are some options that change IL semantics which means
> +         we cannot inline in these cases for correctness reason.
> +	 Not even for always_inline declared functions.  */
> +      /* Strictly speaking only when the callee contains signed integer
> +         math where overflow is undefined.  */
> +      if ((opt_for_fn (e->caller->decl, flag_strict_overflow)
> +	   != opt_for_fn (e->caller->decl, flag_strict_overflow))
> +	  || (opt_for_fn (e->caller->decl, flag_wrapv)
> +	      != opt_for_fn (e->caller->decl, flag_wrapv))
> +	  || (opt_for_fn (e->caller->decl, flag_trapv)
> +	      != opt_for_fn (e->caller->decl, flag_trapv))
> +	  /* Strictly speaking only when the callee contains memory
> +	     accesses that are not using alias-set zero anyway.  */
> +	  || (opt_for_fn (e->caller->decl, flag_strict_aliasing)
> +	      != opt_for_fn (e->caller->decl, flag_strict_aliasing))
> +	  /* Strictly speaking only when the callee uses FP math.  */
> +	  || (opt_for_fn (e->caller->decl, flag_rounding_math)
> +	      != opt_for_fn (e->caller->decl, flag_rounding_math))
> +	  || (opt_for_fn (e->caller->decl, flag_trapping_math)
> +	      != opt_for_fn (e->caller->decl, flag_trapping_math))
> +	  || (opt_for_fn (e->caller->decl, flag_unsafe_math_optimizations)
> +	      != opt_for_fn (e->caller->decl, flag_unsafe_math_optimizations))
> +	  || (opt_for_fn (e->caller->decl, flag_finite_math_only)
> +	      != opt_for_fn (e->caller->decl, flag_finite_math_only))
> +	  || (opt_for_fn (e->caller->decl, flag_signaling_nans)
> +	      != opt_for_fn (e->caller->decl, flag_signaling_nans))
> +	  || (opt_for_fn (e->caller->decl, flag_cx_limited_range)
> +	      != opt_for_fn (e->caller->decl, flag_cx_limited_range))
> +	  || (opt_for_fn (e->caller->decl, flag_signed_zeros)
> +	      != opt_for_fn (e->caller->decl, flag_signed_zeros))
> +	  || (opt_for_fn (e->caller->decl, flag_associative_math)
> +	      != opt_for_fn (e->caller->decl, flag_associative_math))
> +	  || (opt_for_fn (e->caller->decl, flag_reciprocal_math)
> +	      != opt_for_fn (e->caller->decl, flag_reciprocal_math))
> +	  /* Strictly speaking only when the callee contains function
> +	     calls that may end up setting errno.  */
> +	  || (opt_for_fn (e->caller->decl, flag_errno_math)
> +	      != opt_for_fn (e->caller->decl, flag_errno_math)))
> +	{
> +	  e->inline_failed = CIF_OPTIMIZATION_MISMATCH;
> +	  inlinable = false;
> +	}
> +      /* gcc.dg/pr43564.c.  Apply user-forced inline even at -O0.  */
> +      else if (DECL_DISREGARD_INLINE_LIMITS (callee->decl)
> +	       && lookup_attribute ("always_inline",
> +				    DECL_ATTRIBUTES (callee->decl)))
>   	;
> -      /* When user added an attribute, honnor it.  */
> -      else if ((lookup_attribute ("optimize", DECL_ATTRIBUTES (caller->decl))
> -		|| lookup_attribute ("optimize",
> -				     DECL_ATTRIBUTES (callee->decl)))
> -	       && ((opt_for_fn (caller->decl, optimize)
> -		   > opt_for_fn (callee->decl, optimize))
> -		   || (opt_for_fn (caller->decl, optimize_size)
> -		       != opt_for_fn (callee->decl, optimize_size))))
> +      /* When user added an attribute to the callee honor it.  */
> +      else if (lookup_attribute ("optimize", DECL_ATTRIBUTES (callee->decl))
> +	       && opts_for_fn (caller->decl) != opts_for_fn (callee->decl))
>   	{
>   	  e->inline_failed = CIF_OPTIMIZATION_MISMATCH;
>   	  inlinable = false;
>

  reply	other threads:[~2015-01-22 10:23 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-01-22 10:23 Richard Biener
2015-01-22 10:36 ` Christian Bruel [this message]
2015-01-22 11:03   ` Richard Biener
2015-04-17  6:51     ` Christian Bruel
2015-01-22 19:42 ` Jan Hubicka
2015-01-23 10:05   ` Richard Biener

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