diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc
index 3e20538de9f..1275ef75315 100644
--- a/gcc/fold-const.cc
+++ b/gcc/fold-const.cc
@@ -1284,6 +1284,13 @@ poly_int_binop (poly_wide_int &res, enum tree_code code,
 	return false;
       break;
 
+    case BIT_AND_EXPR:
+      if (TREE_CODE (arg2) != INTEGER_CST
+	  || !can_and_p (wi::to_poly_wide (arg1), wi::to_wide (arg2),
+			 &res))
+	return false;
+      break;
+
     case BIT_IOR_EXPR:
       if (TREE_CODE (arg2) != INTEGER_CST
 	  || !can_ior_p (wi::to_poly_wide (arg1), wi::to_wide (arg2),
diff --git a/gcc/gimplify.cc b/gcc/gimplify.cc
index e90220cc2a0..55cab7a74a8 100644
--- a/gcc/gimplify.cc
+++ b/gcc/gimplify.cc
@@ -9301,7 +9301,8 @@ omp_notice_variable (struct gimplify_omp_ctx *ctx, tree decl, bool in_code)
       && (flags & (GOVD_SEEN | GOVD_LOCAL)) == GOVD_SEEN
       && DECL_SIZE (decl))
     {
-      if (TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST)
+      tree size;
+      if (!poly_int_tree_p (DECL_SIZE (decl)))
 	{
 	  splay_tree_node n2;
 	  tree t = DECL_VALUE_EXPR (decl);
@@ -9312,16 +9313,14 @@ omp_notice_variable (struct gimplify_omp_ctx *ctx, tree decl, bool in_code)
 	  n2->value |= GOVD_SEEN;
 	}
       else if (omp_privatize_by_reference (decl)
-	       && TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (decl)))
-	       && (TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (decl))))
-		   != INTEGER_CST))
+	       && (size = TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (decl))))
+	       && !poly_int_tree_p (size))
 	{
 	  splay_tree_node n2;
-	  tree t = TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (decl)));
-	  gcc_assert (DECL_P (t));
-	  n2 = splay_tree_lookup (ctx->variables, (splay_tree_key) t);
+	  gcc_assert (DECL_P (size));
+	  n2 = splay_tree_lookup (ctx->variables, (splay_tree_key) size);
 	  if (n2)
-	    omp_notice_variable (ctx, t, true);
+	    omp_notice_variable (ctx, size, true);
 	}
     }
 
@@ -14581,7 +14580,7 @@ gimplify_adjust_omp_clauses_1 (splay_tree_node n, void *data)
       if ((gimplify_omp_ctxp->region_type & ORT_ACC) == 0)
 	OMP_CLAUSE_MAP_RUNTIME_IMPLICIT_P (clause) = 1;
       if (DECL_SIZE (decl)
-	  && TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST)
+	  && !poly_int_tree_p (DECL_SIZE (decl)))
 	{
 	  tree decl2 = DECL_VALUE_EXPR (decl);
 	  gcc_assert (INDIRECT_REF_P (decl2));
@@ -15322,7 +15321,7 @@ gimplify_adjust_omp_clauses (gimple_seq *pre_p, gimple_seq body, tree *list_p,
 	  if (!DECL_P (decl))
 	    break;
 	  if (DECL_SIZE (decl)
-	      && TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST)
+	      && !poly_int_tree_p (DECL_SIZE (decl)))
 	    {
 	      tree decl2 = DECL_VALUE_EXPR (decl);
 	      gcc_assert (INDIRECT_REF_P (decl2));
diff --git a/gcc/omp-low.cc b/gcc/omp-low.cc
index e369df6e8f1..e1036adab28 100644
--- a/gcc/omp-low.cc
+++ b/gcc/omp-low.cc
@@ -1461,7 +1461,7 @@ scan_sharing_clauses (tree clauses, omp_context *ctx)
 	  else
 	    install_var_field (decl, false, 11, ctx);
 	  if (DECL_SIZE (decl)
-	      && TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST)
+	      && !poly_int_tree_p (DECL_SIZE (decl)))
 	    {
 	      tree decl2 = DECL_VALUE_EXPR (decl);
 	      gcc_assert (INDIRECT_REF_P (decl2));
diff --git a/gcc/poly-int.h b/gcc/poly-int.h
index 7c8901a971a..77f78752e74 100644
--- a/gcc/poly-int.h
+++ b/gcc/poly-int.h
@@ -1906,6 +1906,25 @@ known_alignment (const poly_int<N, Ca> &a)
   return r & -r;
 }
 
+/* Return true if we can compute A & B at compile time, storing the
+   result in RES if so.  */
+
+template<unsigned int N, typename Ca, typename Cb, typename Cr>
+inline typename if_nonpoly<Cb, bool>::type
+can_and_p (const poly_int<N, Ca> &a, Cb b, Cr *result)
+{
+  /* Coefficients 1 and above must be a multiple of something greater
+     than ~B.  */
+  typedef POLY_INT_TYPE (Ca) int_type;
+  if (N >= 2)
+    for (unsigned int i = 1; i < N; i++)
+      if ((-(a.coeffs[i] & -a.coeffs[i]) & ~b) != int_type (0))
+	return false;
+  *result = a;
+  result->coeffs[0] &= b;
+  return true;
+}
+
 /* Return true if we can compute A | B at compile time, storing the
    result in RES if so.  */