re PR tree-optimization/56837 (-ftree-loop-distribute-patterns generates incorrect...

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

	PR tree-optimization/56837
	* tree-loop-distribution.c (classify_partition): For non-zero
	values require that the value has the same precision as its
	mode to be useful as memset value.

	* g++.dg/torture/pr56837.C: New testcase.

From-SVN: r197476

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 26e7f08646e87f956a11a4f85d79ad64b75110d2..8c281007632695f40f404f8bee278c0f8cfcd11f 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2013-04-04  Richard Biener  <rguenther@suse.de>
+
+       PR tree-optimization/56837
+       * tree-loop-distribution.c (classify_partition): For non-zero
+       values require that the value has the same precision as its
+       mode to be useful as memset value.
+
 2013-04-03  Nick Clifton  <nickc@redhat.com>
 
        * config/v850/v850e3v5.md (fmasf4): Use fmaf.s on E3V5

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 6596dce007c34e4666874b80d619973426d28592..a8ecc418f4635d8d1b0a26d4ea0213960d964204 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2013-04-04  Richard Biener  <rguenther@suse.de>
+
+       PR tree-optimization/56837
+       * g++.dg/torture/pr56837.C: New testcase.
+
 2013-04-04  Tobias Burnus  <burnus@net-b.de>
 
        PR fortran/50269

diff --git a/gcc/testsuite/g++.dg/torture/pr56837.C b/gcc/testsuite/g++.dg/torture/pr56837.C
new file mode 100644 (file)
index 0000000..d007122
--- /dev/null
+++ b/gcc/testsuite/g++.dg/torture/pr56837.C
@@ -0,0 +1,20 @@
+// { dg-do run }
+// { dg-options "-ftree-loop-distribute-patterns" }
+
+extern "C" void abort (void);
+extern "C" int memcmp (const void *, const void *, __SIZE_TYPE__);
+
+bool b1[8];
+bool b2[8] = { true, true, true, true, true, true, true, true };
+
+int main()
+{
+  unsigned int i;
+  for(i=0 ; i < 8; i++)
+    b1[i] = true;
+
+  if (memcmp (b1, b2, 8) != 0)
+    abort ();
+
+  return 0;
+}

diff --git a/gcc/tree-loop-distribution.c b/gcc/tree-loop-distribution.c
index 70f71b37c83892822e8967a35d8ce2a6e2f7303b..101efbed0a5477962526b721260718137901cb7b 100644 (file)
--- a/gcc/tree-loop-distribution.c
+++ b/gcc/tree-loop-distribution.c
@@ -942,13 +942,17 @@ classify_partition (loop_p loop, struct graph *rdg, partition_t partition)
       gimple stmt = DR_STMT (single_store);
       tree rhs = gimple_assign_rhs1 (stmt);
       if (!(integer_zerop (rhs)
-           || integer_all_onesp (rhs)
            || real_zerop (rhs)
            || (TREE_CODE (rhs) == CONSTRUCTOR
                && !TREE_CLOBBER_P (rhs))
-           || (INTEGRAL_TYPE_P (TREE_TYPE (rhs))
-               && (TYPE_MODE (TREE_TYPE (gimple_assign_lhs (stmt)))
-                   == TYPE_MODE (unsigned_char_type_node)))))
+           || ((integer_all_onesp (rhs)
+                || (INTEGRAL_TYPE_P (TREE_TYPE (rhs))
+                    && (TYPE_MODE (TREE_TYPE (rhs))
+                        == TYPE_MODE (unsigned_char_type_node))))
+               /* For stores of a non-zero value require that the precision
+                  of the value matches its actual size.  */
+               && (TYPE_PRECISION (TREE_TYPE (rhs))
+                   == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (rhs)))))))
        return;
       if (TREE_CODE (rhs) == SSA_NAME
          && !SSA_NAME_IS_DEFAULT_DEF (rhs)