re PR tree-optimization/83277 ([graphite] Wrong code w/ -O2 -floop-nest-optimize)

2017-12-05  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/83277
	* graphite-isl-ast-to-gimple.c (should_copy_to_new_region): Make sure
	to code-gen liveout vars.

	* gcc.dg/graphite/pr83277.c: New testcase.

From-SVN: r255424

gcc/ChangeLog

+2017-12-05  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/83277
+	* graphite-isl-ast-to-gimple.c (should_copy_to_new_region): Make sure
+	to code-gen liveout vars.
+
 2017-12-05  Richard Sandiford  <richard.sandiford@linaro.org>
 
 	* config/aarch64/aarch64-simd.md (aarch64_simd_bsldi_internal)

gcc/graphite-isl-ast-to-gimple.c

@@ -1137,8 +1137,10 @@ should_copy_to_new_region (gimple *stmt, sese_info_p region)
   if (is_gimple_assign (stmt)
       && (lhs = gimple_assign_lhs (stmt))
       && TREE_CODE (lhs) == SSA_NAME
-      && is_gimple_reg (lhs)
-      && scev_analyzable_p (lhs, region->region))
+      && scev_analyzable_p (lhs, region->region)
+      /* But to code-generate liveouts - liveout PHI generation is
+         in generic sese.c code that cannot do code generation.  */
+      && ! bitmap_bit_p (region->liveout, SSA_NAME_VERSION (lhs)))
     return false;
 
   return true;

gcc/testsuite/ChangeLog

+2017-12-05  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/83277
+	* gcc.dg/graphite/pr83277.c: New testcase.
+
 2017-12-05  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/83283

gcc/testsuite/gcc.dg/graphite/pr83277.c

+/* { dg-do run } */
+/* { dg-options "-O2 -floop-nest-optimize" } */
+
+int rk, si = 0;
+int jr[2];
+
+int
+wv (signed char n8)
+{
+  const int tw = 8;
+  int xq[tw];
+  int bj, pu = 0;
+
+  for (bj = 0; bj < tw; ++bj)
+    xq[bj] = 0;
+
+  bj = 0;
+  while (bj < 1)
+    {
+      int gs = n8 ^ 128;
+
+      if (gs != 0)
+	{
+	  int u7[3];
+
+	  while (bj < 2)
+	    {
+	      u7[bj] = 0;
+	      ++bj;
+	    }
+
+	  jr[0] = u7[0];
+	  rk = xq[0];
+	  pu = n8;
+
+	  if (si != 0)
+	    return si;
+	}
+    }
+
+  return pu;
+}
+
+int
+main (void)
+{
+  signed char ax = 1;
+
+  if (wv (ax) != ax)
+    __builtin_abort ();
+  return 0;
+}