From: Jan Hubicka <hubicka@ucw.cz>
Date: Sat, 25 Jun 2016 11:56:52 +0000 (+0200)
Subject: predict.c: Include ipa-utils.h
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=888ed1a39a46d55a7c1f2357d31eb4b59e4dc721;p=gcc.git

predict.c: Include ipa-utils.h

	* predict.c: Include ipa-utils.h
	(tree_bb_level_prediction): Predict recursive calls.
	(tree_estimate_probability_bb): Skip inexpensive calls for call
	predictor.
	* predict.def (PRED_RECURSIVE_CALL): New.

	* gcc.dg/predict-10.c: New test.

From-SVN: r237780
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index a88fd1824f7..121119cb210 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2016-06-24  Jan Hubicka  <hubicka@ucw.cz>
+
+	* predict.c: Include ipa-utils.h
+	(tree_bb_level_prediction): Predict recursive calls.
+	(tree_estimate_probability_bb): Skip inexpensive calls for call
+	predictor.
+	* predict.def (PRED_RECURSIVE_CALL): New.
+
 2016-06-24  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>
 
 	* config/rs6000/rs6000-builtin.def (BU_FLOAT128_2): New #define.
diff --git a/gcc/predict.c b/gcc/predict.c
index d505d9c4cc8..cc4302b1b7e 100644
--- a/gcc/predict.c
+++ b/gcc/predict.c
@@ -54,6 +54,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "tree-ssa-loop-niter.h"
 #include "tree-ssa-loop.h"
 #include "tree-scalar-evolution.h"
+#include "ipa-utils.h"
 
 /* Enum with reasons why a predictor is ignored.  */
 
@@ -2425,6 +2426,9 @@ tree_bb_level_predictions (void)
 				       DECL_ATTRIBUTES (decl)))
 		predict_paths_leading_to (bb, PRED_COLD_FUNCTION,
 					  NOT_TAKEN);
+	      if (decl && recursive_call_p (current_function_decl, decl))
+		predict_paths_leading_to (bb, PRED_RECURSIVE_CALL,
+					  NOT_TAKEN);
 	    }
 	  else if (gimple_code (stmt) == GIMPLE_PREDICT)
 	    {
@@ -2539,6 +2543,7 @@ tree_estimate_probability_bb (basic_block bb)
 	    {
 	      gimple *stmt = gsi_stmt (bi);
 	      if (is_gimple_call (stmt)
+		  && !gimple_inexpensive_call_p (as_a <gcall *>  (stmt))
 		  /* Constant and pure calls are hardly used to signalize
 		     something exceptional.  */
 		  && gimple_has_side_effects (stmt))
diff --git a/gcc/predict.def b/gcc/predict.def
index d3bc757bb97..2f6d6cd4d08 100644
--- a/gcc/predict.def
+++ b/gcc/predict.def
@@ -112,6 +112,9 @@ DEF_PREDICTOR (PRED_TREE_FPOPCODE, "fp_opcode (on trees)", HITRATE (90), 0)
 /* Branch guarding call is probably taken.  */
 DEF_PREDICTOR (PRED_CALL, "call", HITRATE (67), 0)
 
+/* Recursive calls are usually not taken or the function will recurse indefinitely.  */
+DEF_PREDICTOR (PRED_RECURSIVE_CALL, "recursive call", HITRATE (75), 0)
+
 /* Branch causing function to terminate is probably not taken. 
    FIXME: early return currently predicts code:
    int foo (int a)
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index f373b0e2774..404b8144fb1 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2016-06-24  Jan Hubicka  <hubicka@ucw.cz>
+
+	* gcc.dg/predict-10.c: New test.
+
 2016-06-24  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>
 
 	* gcc.target/powerpc/abs128-1.c: New.
diff --git a/gcc/testsuite/gcc.dg/predict-10.c b/gcc/testsuite/gcc.dg/predict-10.c
new file mode 100644
index 00000000000..a99819a24c6
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/predict-10.c
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-profile_estimate" } */
+int
+ee(int i)
+{
+  if (i>2)
+    return (ee(i-1)+ee(i-2))/2;
+  else
+    return i;
+}
+/* { dg-final { scan-tree-dump-times "recursive call" 1 "profile_estimate"} } */