re PR tree-optimization/56812 (Simple loop is not SLP-vectorized after r196872)

2013-04-03  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/56812
	* tree-vect-data-refs.c (vect_slp_analyze_data_ref_dependence):
	DRs of the same interleaving chain are independent.

	* g++.dg/vect/slp-pr56812.cc: New testcase.

From-SVN: r197390

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 788f2b04abf5518bf14745a483396a43a5a0396c..db0f7a697396591562e75fce086ad51257977f1f 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2013-04-03  Richard Biener  <rguenther@suse.de>
+
+       PR tree-optimization/56812
+       * tree-vect-data-refs.c (vect_slp_analyze_data_ref_dependence):
+       DRs of the same interleaving chain are independent.
+
 2013-04-02  Jason Merrill  <jason@redhat.com>
 
        * gdbinit.in (pbb): Use debug fn.

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index e025a242f66485cbea7cb4b5032fc75e15066cdb..4a6c3b88b3c4a01d4c890c9a93d8f73e0017b20a 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2013-04-03  Richard Biener  <rguenther@suse.de>
+
+       PR tree-optimization/56812
+       * g++.dg/vect/slp-pr56812.cc: New testcase.
+
 2013-04-03  Janus Weil  <janus@gcc.gnu.org>
 
        PR fortran/56284

diff --git a/gcc/testsuite/g++.dg/vect/slp-pr56812.cc b/gcc/testsuite/g++.dg/vect/slp-pr56812.cc
new file mode 100644 (file)
index 0000000..d27b4a8
--- /dev/null
+++ b/gcc/testsuite/g++.dg/vect/slp-pr56812.cc
@@ -0,0 +1,20 @@
+/* { dg-do compile } */\r
+/* { dg-require-effective-target vect_float } */\r
+/* { dg-options "-O3 -funroll-loops -fdump-tree-slp-details" } */\r
+\r
+class mydata {\r
+public:\r
+    mydata() {Set(-1.0);}\r
+    void Set (float);\r
+    static int upper() {return 8;}\r
+    float data[8];\r
+};\r
+\r
+void mydata::Set (float x)\r
+{\r
+  for (int i=0; i<upper(); i++)\r
+    data[i] = x;\r
+}\r
+\r
+/* { dg-final { scan-tree-dump-times "basic block vectorized using SLP" 1 "slp" } } */\r
+/* { dg-final { cleanup-tree-dump "slp" } } */\r

diff --git a/gcc/tree-vect-data-refs.c b/gcc/tree-vect-data-refs.c
index 4ef9ba86ef322c3df7c86e556705ff2ad05710f6..128e874392b1a3286bfc41d1198f4f6759e7ec06 100644 (file)
--- a/gcc/tree-vect-data-refs.c
+++ b/gcc/tree-vect-data-refs.c
@@ -484,6 +484,13 @@ vect_slp_analyze_data_ref_dependence (struct data_dependence_relation *ddr)
   if (DR_IS_READ (dra) && DR_IS_READ (drb))
     return false;
 
+  /* If dra and drb are part of the same interleaving chain consider
+     them independent.  */
+  if (STMT_VINFO_GROUPED_ACCESS (vinfo_for_stmt (DR_STMT (dra)))
+      && (GROUP_FIRST_ELEMENT (vinfo_for_stmt (DR_STMT (dra)))
+         == GROUP_FIRST_ELEMENT (vinfo_for_stmt (DR_STMT (drb)))))
+    return false;
+
   /* Unknown data dependence.  */
   if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know)
     {