From: H.J. Lu <hongjiu.lu@intel.com>
Date: Tue, 2 Dec 2014 14:10:23 +0000 (+0000)
Subject: Stop only if there aren't any usable algorithms
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=0f884e6709dac066e558c6a63c50a5149ab408f3;p=gcc.git

Stop only if there aren't any usable algorithms

When searching for an usable algorithm with -minline-all-stringops,
decide_alg stops when it sees libcall even if there is a usable
algorithm.  It goes into an infinite loop.  This patch changes
decide_alg to stop searching only if there aren't any usable algorithms.
Testd on Linux/x86-64.


gcc/

	PR target/64108
	* config/i386/i386.c (decide_alg): Stop only if there aren't
	any usable algorithms.

gcc/testsuite/

	PR target/64108
	* gcc.target/i386/memset-strategy-2.c: New test.

From-SVN: r218272
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 3eacc5a2588..c746d0f8a51 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2014-12-02  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR target/64108
+	* config/i386/i386.c (decide_alg): Stop only if there aren't
+	any usable algorithms.
+
 2014-12-02  Tom de Vries  <tom@codesourcery.com>
 
 	PR rtl-optimization/63718
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 33971671790..211c9e6a65e 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -24464,7 +24464,8 @@ decide_alg (HOST_WIDE_INT count, HOST_WIDE_INT expected_size,
 		      *noalign = alg_noalign;
 		      return alg;
 		    }
-		  break;
+		  else if (!any_alg_usable_p)
+		    break;
 		}
 	      else if (alg_usable_p (candidate, memset))
 		{
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 00da0bdbdde..5d668494f8a 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2014-12-02  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR target/64108
+	* gcc.target/i386/memset-strategy-2.c: New test.
+
 2014-12-02  Richard Biener  <rguenther@suse.de>
 
 	* gcc.dg/torture/20141202-1.c: New testcase.
diff --git a/gcc/testsuite/gcc.target/i386/memset-strategy-2.c b/gcc/testsuite/gcc.target/i386/memset-strategy-2.c
new file mode 100644
index 00000000000..aafa54d004f
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/memset-strategy-2.c
@@ -0,0 +1,10 @@
+/* PR target/64108 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -march=atom -mmemset-strategy=libcall:-1:align -minline-all-stringops" } */
+
+char a[2048];
+void t (void)
+{
+  __builtin_memset (a, 1, 2048);
+}
+