Allow the front-end to create calls with a static chain

And, at the same time, allow indirect calls to have a static chain.
We'll always eliminate the static chain if we can prove it's unused.

        * calls.c (prepare_call_address): Allow decl or type for first arg.
        (expand_call): Pass type to prepare_call_address if no decl.
        * gimple-fold.c (gimple_fold_call): Eliminate the static chain if
        the function doesn't use it; fold it otherwise.
        * gimplify.c (gimplify_call_expr): Gimplify the static chain.
        * tree-cfg.c (verify_gimple_call): Allow a static chain on indirect
        function calls.

From-SVN: r217770

1 files changed, 21 insertions, 0 deletions

diff --git a/gcc/gimple-fold.c b/gcc/gimple-fold.c
index acdadcd..4f716b2 100644
--- a/gcc/gimple-fold.c
+++ b/gcc/gimple-fold.c
@@ -2723,6 +2723,27 @@ gimple_fold_call (gimple_stmt_iterator *gsi, bool inplace)
 	}
     }
 
+  /* Check for indirect calls that became direct calls, and then
+     no longer require a static chain.  */
+  if (gimple_call_chain (stmt))
+    {
+      tree fn = gimple_call_fndecl (stmt);
+      if (fn && !DECL_STATIC_CHAIN (fn))
+	{
+	  gimple_call_set_chain (stmt, NULL);
+	  changed = true;
+	}
+      else
+	{
+	  tree tmp = maybe_fold_reference (gimple_call_chain (stmt), false);
+	  if (tmp)
+	    {
+	      gimple_call_set_chain (stmt, tmp);
+	      changed = true;
+	    }
+	}
+    }
+
   if (inplace)
     return changed;