From: Martin Jambor <mjambor@suse.cz>
Date: Thu, 14 Mar 2019 16:54:43 +0000 (+0100)
Subject: Zero local estimated benefit for cloning extern inline function
X-Git-Tag: releases/gcc-7.5.0~540
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=618e48ada6183eaf6846e8b0cbc866f9de094ac8;p=thirdparty%2Fgcc.git

Zero local estimated benefit for cloning extern inline function

2019-03-14  Martin Jambor  <mjambor@suse.cz>

	Backport from mainline
	2019-03-07  Martin Jambor  <mjambor@suse.cz>

	PR lto/87525
	* ipa-cp.c (perform_estimation_of_a_value): Account zero time benefit
	for extern inline functions.

	testsuite/
	* gcc.dg/ipa/ipcp-5.c: New test.

From-SVN: r269688
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d3f9e5b1fd76..288c1ac1fff7 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2019-03-14  Martin Jambor  <mjambor@suse.cz>
+
+	Backport from mainline
+	2019-03-07  Martin Jambor  <mjambor@suse.cz>
+
+	PR lto/87525
+	* ipa-cp.c (perform_estimation_of_a_value): Account zero time benefit
+	for extern inline functions.
+
 2019-03-14  Richard Biener  <rguenther@suse.de>
 
 	Backport from mainline
diff --git a/gcc/ipa-cp.c b/gcc/ipa-cp.c
index b42cfb0f6e02..56a95754c7f2 100644
--- a/gcc/ipa-cp.c
+++ b/gcc/ipa-cp.c
@@ -2819,11 +2819,18 @@ perform_estimation_of_a_value (cgraph_node *node, vec<tree> known_csts,
   estimate_ipcp_clone_size_and_time (node, known_csts, known_contexts,
 				     known_aggs_ptrs, &size, &time,
 				     &hints);
-  time_benefit = base_time - time
-    + devirtualization_time_bonus (node, known_csts, known_contexts,
-				   known_aggs_ptrs)
-    + hint_time_bonus (hints)
-    + removable_params_cost + est_move_cost;
+
+  /* Extern inline functions have no cloning local time benefits because they
+     will be inlined anyway.  The only reason to clone them is if it enables
+     optimization in any of the functions they call.  */
+  if (DECL_EXTERNAL (node->decl) && DECL_DECLARED_INLINE_P (node->decl))
+    time_benefit = 0;
+  else
+    time_benefit = base_time - time
+      + devirtualization_time_bonus (node, known_csts, known_contexts,
+				     known_aggs_ptrs)
+      + hint_time_bonus (hints)
+      + removable_params_cost + est_move_cost;
 
   gcc_checking_assert (size >=0);
   /* The inliner-heuristics based estimates may think that in certain
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 6061fba0b365..c4312ffa2710 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2019-03-14  Martin Jambor  <mjambor@suse.cz>
+
+	Backport from mainline
+	2019-03-07  Martin Jambor  <mjambor@suse.cz>
+
+	PR lto/87525
+	* gcc.dg/ipa/ipcp-5.c: New test.
+
 2019-03-14  Richard Biener  <rguenther@suse.de>
 
 	Backport from mainline
diff --git a/gcc/testsuite/gcc.dg/ipa/ipcp-5.c b/gcc/testsuite/gcc.dg/ipa/ipcp-5.c
new file mode 100644
index 000000000000..6786c5145434
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ipa/ipcp-5.c
@@ -0,0 +1,45 @@
+/* Test that estimated local cloning time benefit of extern inline functions is
+   zero.  */
+
+/* { dg-do compile } */
+/* { dg-options "-O3 -fdump-ipa-cp -fno-early-inlining"  } */
+/* { dg-add-options bind_pic_locally } */
+
+extern int get_int (void);
+extern void use_stuff (int);
+
+int arr[10];
+
+inline void
+f (int a)
+{
+  arr[0] += a + 5;
+  arr[1] += a + 50;
+  arr[2] += a - 3;
+  arr[3] += a;
+  arr[4] += a + 21;
+  arr[5] += a + 900;
+  arr[6] += a + 2;
+  arr[7] += a + 3456;
+  arr[8] += a + 3;
+  arr[9] += a + 32;
+  use_stuff (a);
+}
+
+
+int
+entry (void)
+{
+  int i;
+  for (i = 0; i < 100; i++)
+    f (7);
+  for (i = 0; i < 100; i++)
+    f (get_int ());
+  return 0;
+}
+
+
+/* { dg-final { scan-ipa-dump "loc_time: 0" "cp" } } */
+/* { dg-final { scan-ipa-dump-not "replacing param.*with const" "cp"  } } */
+
+