re PR middle-end/39154 (Miscompilation of VLAs in nested parallel regions)

PR middle-end/39154
	* gimplify.c (omp_notice_variable): If adding GOVD_SEEN
	bit to variable length decl's flags, add it also to its
	pointer replacement variable.

	* testsuite/libgomp.c/pr39154.c: New test.

From-SVN: r144111

gcc/ChangeLog

@@ -1,3 +1,10 @@
+2009-02-11  Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/39154
+	* gimplify.c (omp_notice_variable): If adding GOVD_SEEN
+	bit to variable length decl's flags, add it also to its
+	pointer replacement variable.
+
 2009-02-11  Uros Bizjak  <ubizjak@gmail.com>
 	    Jakub Jelinek  <jakub@redhat.com>
 

gcc/gimplify.c

@@ -5308,6 +5308,20 @@ omp_notice_variable (struct gimplify_omp_ctx *ctx, tree decl, bool in_code)
       goto do_outer;
     }
 
+  if ((n->value & (GOVD_SEEN | GOVD_LOCAL)) == 0
+      && (flags & (GOVD_SEEN | GOVD_LOCAL)) == GOVD_SEEN
+      && DECL_SIZE (decl)
+      && TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST)
+    {
+      splay_tree_node n2;
+      tree t = DECL_VALUE_EXPR (decl);
+      gcc_assert (TREE_CODE (t) == INDIRECT_REF);
+      t = TREE_OPERAND (t, 0);
+      gcc_assert (DECL_P (t));
+      n2 = splay_tree_lookup (ctx->variables, (splay_tree_key) t);
+      n2->value |= GOVD_SEEN;
+    }
+
   shared = ((flags | n->value) & GOVD_SHARED) != 0;
   ret = lang_hooks.decls.omp_disregard_value_expr (decl, shared);
 

libgomp/ChangeLog

@@ -1,3 +1,8 @@
+2009-02-11  Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/39154
+	* testsuite/libgomp.c/pr39154.c: New test.
+
 2009-01-30  Ian Lance Taylor  <iant@google.com>
 
 	* acinclude.m4 (LIBCOMP_CHECK_LINKER_FEATURES): Set

libgomp/testsuite/libgomp.c/pr39154.c

@@ -0,0 +1,105 @@
+/* PR middle-end/39154 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -std=gnu99" } */
+
+extern void abort (void);
+
+int n = 20;
+
+int
+main (void)
+{
+  int a[n], b[n][n];
+
+#pragma omp parallel for
+    for (int i = 0; i < n; i++)
+      {
+	a[i] = i + 1;
+#pragma omp parallel for
+	for (int j = 0; j < n; j++)
+	  b[i][j] = a[i];
+      }
+
+  for (int i = 0; i < n; i++)
+    {
+      for (int j = 0; j < n; j++)
+	if (b[i][j] != i + 1)
+	  abort ();
+      if (a[i] != i + 1)
+	abort ();
+    }
+
+#pragma omp parallel for shared (n, a, b)
+    for (int i = 0; i < n; i++)
+      {
+	a[i] = i + 3;
+#pragma omp parallel for
+	for (int j = 0; j < n; j++)
+	  b[i][j] = a[i];
+      }
+
+  for (int i = 0; i < n; i++)
+    {
+      for (int j = 0; j < n; j++)
+	if (b[i][j] != i + 3)
+	  abort ();
+      if (a[i] != i + 3)
+	abort ();
+    }
+
+#pragma omp parallel for
+    for (int i = 0; i < n; i++)
+      {
+	a[i] = i + 5;
+#pragma omp parallel for shared (n, a, b)
+	for (int j = 0; j < n; j++)
+	  b[i][j] = a[i];
+      }
+
+  for (int i = 0; i < n; i++)
+    {
+      for (int j = 0; j < n; j++)
+	if (b[i][j] != i + 5)
+	  abort ();
+      if (a[i] != i + 5)
+	abort ();
+    }
+
+#pragma omp parallel for shared (n, a, b)
+    for (int i = 0; i < n; i++)
+      {
+	a[i] = i + 7;
+#pragma omp parallel for shared (n, a, b)
+	for (int j = 0; j < n; j++)
+	  b[i][j] = a[i];
+      }
+
+  for (int i = 0; i < n; i++)
+    {
+      for (int j = 0; j < n; j++)
+	if (b[i][j] != i + 7)
+	  abort ();
+      if (a[i] != i + 7)
+	abort ();
+    }
+
+#pragma omp parallel for private (a, b)
+    for (int i = 0; i < n; i++)
+      {
+	a[i] = i + 1;
+#pragma omp parallel for
+	for (int j = 0; j < n; j++)
+	  b[i][j] = a[i];
+      }
+
+#pragma omp parallel for private (a, b)
+    for (int i = 0; i < n; i++)
+      {
+	a[i] = i + 1;
+#pragma omp parallel for private (b)
+	for (int j = 0; j < n; j++)
+	  b[i][j] = a[i];
+      }
+
+  return 0;
+}