From: Jakub Jelinek <jakub@redhat.com>
Date: Thu, 7 Jul 2016 21:47:40 +0000 (+0200)
Subject: backport: re PR rtl-optimization/69891 (wrong code with -mstringop-strategy=libcall... 
X-Git-Tag: releases/gcc-4.9.4~93
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=da13cc2eb9771a140cbd7c7cdb67b08206a49305;p=thirdparty%2Fgcc.git

backport: re PR rtl-optimization/69891 (wrong code with -mstringop-strategy=libcall @ i686)

	Backported from mainline
	2016-02-26  Jakub Jelinek  <jakub@redhat.com>
		    Eric Botcazou  <ebotcazou@adacore.com>

	PR rtl-optimization/69891
	* dse.c (scan_insn): If we can't figure out memset arguments
	or they are non-constant, call clear_rhs_from_active_local_stores.

	* gcc.target/i386/pr69891.c: New test.

From-SVN: r238137
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 5cb436212f0e..77a3af91ddd2 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,6 +1,13 @@
 2016-07-07  Jakub Jelinek  <jakub@redhat.com>
 
 	Backported from mainline
+	2016-02-26  Jakub Jelinek  <jakub@redhat.com>
+		    Eric Botcazou  <ebotcazou@adacore.com>
+
+	PR rtl-optimization/69891
+	* dse.c (scan_insn): If we can't figure out memset arguments
+	or they are non-constant, call clear_rhs_from_active_local_stores.
+
 	2016-02-16  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/69802
diff --git a/gcc/dse.c b/gcc/dse.c
index 9392f6bccc1b..2aa5af0d5ca8 100644
--- a/gcc/dse.c
+++ b/gcc/dse.c
@@ -2582,6 +2582,8 @@ scan_insn (bb_info_t bb_info, rtx insn)
 		      active_local_stores = insn_info;
 		    }
 		}
+	      else
+		clear_rhs_from_active_local_stores ();
 	    }
 	}
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 7fc70834ed63..96a3b621674d 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,6 +1,12 @@
 2016-07-07  Jakub Jelinek  <jakub@redhat.com>
 
 	Backported from mainline
+	2016-02-26  Jakub Jelinek  <jakub@redhat.com>
+		    Eric Botcazou  <ebotcazou@adacore.com>
+
+	PR rtl-optimization/69891
+	* gcc.target/i386/pr69891.c: New test.
+
 	2016-02-19  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/67767
diff --git a/gcc/testsuite/gcc.target/i386/pr69891.c b/gcc/testsuite/gcc.target/i386/pr69891.c
new file mode 100644
index 000000000000..2c5e86372e3e
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr69891.c
@@ -0,0 +1,30 @@
+/* PR rtl-optimization/69891 */
+/* { dg-do run } */
+/* { dg-options "-O -fno-tree-fre -mstringop-strategy=libcall -Wno-psabi" } */
+/* { dg-additional-options "-mno-sse" { target ia32 } } */
+
+typedef unsigned short A;
+typedef unsigned short B __attribute__ ((vector_size (32)));
+typedef unsigned int C;
+typedef unsigned int D __attribute__ ((vector_size (32)));
+typedef unsigned long long E;
+typedef unsigned long long F __attribute__ ((vector_size (32)));
+
+__attribute__((noinline, noclone)) unsigned
+foo(D a, B b, D c, F d)
+{
+  b /= (B) {1, -c[0]} | 1;
+  c[0] |= 7;
+  a %= c | 1;
+  c ^= c;
+  return a[0] + b[15] + c[0] + d[3];
+}
+
+int
+main ()
+{
+  unsigned x = foo ((D) {}, (B) {}, (D) {}, (F) {});
+  if (x != 0)
+    __builtin_abort ();
+  return 0;
+}