2019-08-30  Jakub Jelinek  <jakub@redhat.com>

	Backported from mainline
	2019-03-13  Jakub Jelinek  <jakub@redhat.com>

	PR middle-end/88588
	* omp-simd-clone.c (ipa_simd_modify_stmt_ops): Handle PHI args.
	(ipa_simd_modify_function_body): Handle PHIs.

	* c-c++-common/gomp/pr88588.c: New test.

--- gcc/omp-simd-clone.c	(revision 270725)
+++ gcc/omp-simd-clone.c	(revision 270726)
@@ -868,6 +868,18 @@ ipa_simd_modify_stmt_ops (tree *tp, int
 
   if (tp != orig_tp)
     {
+      if (gimple_code (info->stmt) == GIMPLE_PHI
+	  && cand
+	  && TREE_CODE (*orig_tp) == ADDR_EXPR
+	  && TREE_CODE (TREE_OPERAND (*orig_tp, 0)) == PARM_DECL
+	  && cand->alias_ptr_type)
+	{
+	  gcc_assert (TREE_CODE (cand->alias_ptr_type) == SSA_NAME);
+	  *orig_tp = cand->alias_ptr_type;
+	  info->modified = true;
+	  return NULL_TREE;
+	}
+
       repl = build_fold_addr_expr (repl);
       gimple *stmt;
       if (is_gimple_debug (info->stmt))
@@ -884,7 +896,18 @@ ipa_simd_modify_stmt_ops (tree *tp, int
 	  stmt = gimple_build_assign (make_ssa_name (TREE_TYPE (repl)), repl);
 	  repl = gimple_assign_lhs (stmt);
 	}
-      gimple_stmt_iterator gsi = gsi_for_stmt (info->stmt);
+      gimple_stmt_iterator gsi;
+      if (gimple_code (info->stmt) == GIMPLE_PHI)
+	{
+	  gsi = gsi_after_labels (single_succ (ENTRY_BLOCK_PTR_FOR_FN (cfun)));
+	  /* Cache SSA_NAME for next time.  */
+	  if (cand
+	      && TREE_CODE (*orig_tp) == ADDR_EXPR
+	      && TREE_CODE (TREE_OPERAND (*orig_tp, 0)) == PARM_DECL)
+	    cand->alias_ptr_type = repl;
+	}
+      else
+	gsi = gsi_for_stmt (info->stmt);
       gsi_insert_before (&gsi, stmt, GSI_SAME_STMT);
       *orig_tp = repl;
     }
@@ -985,6 +1008,31 @@ ipa_simd_modify_function_body (struct cg
     {
       gimple_stmt_iterator gsi;
 
+      for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+	{
+	  gphi *phi = as_a <gphi *> (gsi_stmt (gsi));
+	  int i, n = gimple_phi_num_args (phi);
+	  info.stmt = phi;
+	  struct walk_stmt_info wi;
+	  memset (&wi, 0, sizeof (wi));
+	  info.modified = false;
+	  wi.info = &info;
+	  for (i = 0; i < n; ++i)
+	    {
+	      int walk_subtrees = 1;
+	      tree arg = gimple_phi_arg_def (phi, i);
+	      tree op = arg;
+	      ipa_simd_modify_stmt_ops (&op, &walk_subtrees, &wi);
+	      if (op != arg)
+		{
+		  SET_PHI_ARG_DEF (phi, i, op);
+		  gcc_assert (TREE_CODE (op) == SSA_NAME);
+		  if (gimple_phi_arg_edge (phi, i)->flags & EDGE_ABNORMAL)
+		    SSA_NAME_OCCURS_IN_ABNORMAL_PHI (op) = 1;
+		}
+	    }
+	}
+
       gsi = gsi_start_bb (bb);
       while (!gsi_end_p (gsi))
 	{
--- gcc/testsuite/c-c++-common/gomp/pr88588.c	(nonexistent)
+++ gcc/testsuite/c-c++-common/gomp/pr88588.c	(revision 270726)
@@ -0,0 +1,18 @@
+/* PR middle-end/88588 */
+/* { dg-do compile } */
+/* { dg-options "-fopenmp -O1" } */
+
+int *v;
+
+#pragma omp declare simd
+void
+foo (int x)
+{
+  int *a = &x;
+
+  for (;;)
+    {
+      *v = *a;
+      a = v;
+    }
+}