re PR middle-end/83665 (Big code size regression and some code quality improvement at Jan 2 2018)

	PR middle-end/83665
	* params.def (inline-min-speedup): Increase from 8 to 15.
	(max-inline-insns-auto): Decrease from 40 to 30.
	* ipa-split.c (consider_split): Add some buffer for function to
	be considered inlining candidate.
	* invoke.texi (max-inline-insns-auto, inline-min-speedup): UPdate
	default values.

From-SVN: r257582

gcc/ChangeLog

+2018-02-08  Jan Hubicka  <hubicka@ucw.cz>
+
+	PR middle-end/83665
+	* params.def (inline-min-speedup): Increase from 8 to 15.
+	(max-inline-insns-auto): Decrease from 40 to 30.
+	* ipa-split.c (consider_split): Add some buffer for function to
+	be considered inlining candidate.
+	* invoke.texi (max-inline-insns-auto, inline-min-speedup): UPdate
+	default values.
+
 2018-02-12  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/84037

gcc/doc/invoke.texi

@@ -10131,13 +10131,14 @@ a lot of functions that would otherwise not be considered for inlining
 by the compiler are investigated.  To those functions, a different
 (more restrictive) limit compared to functions declared inline can
 be applied.
-The default value is 40.
+The default value is 30.
 
 @item inline-min-speedup
 When estimated performance improvement of caller + callee runtime exceeds this
 threshold (in percent), the function can be inlined regardless of the limit on
 @option{--param max-inline-insns-single} and @option{--param
 max-inline-insns-auto}.
+The default value is 15.
 
 @item large-function-insns
 The limit specifying really large functions.  For functions larger than this

gcc/ipa-split.c

@@ -558,10 +558,13 @@ consider_split (struct split_point *current, bitmap non_ssa_vars,
 		 "  Refused: split size is smaller than call overhead\n");
       return;
     }
+  /* FIXME: The logic here is not very precise, because inliner does use
+     inline predicates to reduce function body size.  We add 10 to anticipate
+     that.  Next stage1 we should try to be more meaningful here.  */
   if (current->header_size + call_overhead
       >= (unsigned int)(DECL_DECLARED_INLINE_P (current_function_decl)
 			? MAX_INLINE_INSNS_SINGLE
-			: MAX_INLINE_INSNS_AUTO))
+			: MAX_INLINE_INSNS_AUTO) + 10)
     {
       if (dump_file && (dump_flags & TDF_DETAILS))
 	fprintf (dump_file,
@@ -574,7 +577,7 @@ consider_split (struct split_point *current, bitmap non_ssa_vars,
      Limit this duplication.  This is consistent with limit in tree-sra.c  
      FIXME: with LTO we ought to be able to do better!  */
   if (DECL_ONE_ONLY (current_function_decl)
-      && current->split_size >= (unsigned int) MAX_INLINE_INSNS_AUTO)
+      && current->split_size >= (unsigned int) MAX_INLINE_INSNS_AUTO + 10)
     {
       if (dump_file && (dump_flags & TDF_DETAILS))
 	fprintf (dump_file,

gcc/params.def

@@ -52,13 +52,13 @@ DEFPARAM (PARAM_PREDICTABLE_BRANCH_OUTCOME,
 DEFPARAM (PARAM_INLINE_MIN_SPEEDUP,
 	  "inline-min-speedup",
 	  "The minimal estimated speedup allowing inliner to ignore inline-insns-single and inline-insns-auto.",
-	  8, 0, 0)
+	  15, 0, 0)
 
 /* The single function inlining limit. This is the maximum size
    of a function counted in internal gcc instructions (not in
    real machine instructions) that is eligible for inlining
    by the tree inliner.
-   The default value is 450.
+   The default value is 400.
    Only functions marked inline (or methods defined in the class
    definition for C++) are affected by this.
    There are more restrictions to inlining: If inlined functions
@@ -77,11 +77,11 @@ DEFPARAM (PARAM_MAX_INLINE_INSNS_SINGLE,
    that is applied to functions marked inlined (or defined in the
    class declaration in C++) given by the "max-inline-insns-single"
    parameter.
-   The default value is 40.  */
+   The default value is 30.  */
 DEFPARAM (PARAM_MAX_INLINE_INSNS_AUTO,
 	  "max-inline-insns-auto",
 	  "The maximum number of instructions when automatically inlining.",
-	  40, 0, 0)
+	  30, 0, 0)
 
 DEFPARAM (PARAM_MAX_INLINE_INSNS_RECURSIVE,
 	  "max-inline-insns-recursive",