From: Richard Kenner <kenner@gcc.gnu.org>
Date: Tue, 24 Sep 1996 12:13:52 +0000 (-0400)
Subject: (expand_inline_function): Avoid creating paradoxical subreg wider than
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=2d0bd5fde06d1538ee95376c0b41a598feb9579d;p=gcc.git

(expand_inline_function): Avoid creating paradoxical subreg wider than
BITS_PER_WORD as inlined function result.

From-SVN: r12832
---

diff --git a/gcc/integrate.c b/gcc/integrate.c
index f1e778a81d8..1c5a4a7dd63 100644
--- a/gcc/integrate.c
+++ b/gcc/integrate.c
@@ -1673,7 +1673,21 @@ expand_inline_function (fndecl, parms, target, ignore, type,
 	 avoid machine mode mismatch when we substitute INLINE_TARGET.
 	 But TARGET is what we will return to the caller.  */
       if (arriving_mode != departing_mode)
-	reg_to_map = gen_rtx (SUBREG, arriving_mode, target, 0);
+	{
+	  /* Avoid creating a paradoxical subreg wider than
+	     BITS_PER_WORD, since that is illegal.  */
+	  if (GET_MODE_BITSIZE (arriving_mode) > BITS_PER_WORD)
+	    {
+	      if (!TRULY_NOOP_TRUNCATION (GET_MODE_BITSIZE (departing_mode),
+					  GET_MODE_BITSIZE (arriving_mode)))
+		/* Maybe could be handled by using convert_move () ?  */
+		abort ();
+	      reg_to_map = gen_reg_rtx (arriving_mode);
+	      target = gen_lowpart (departing_mode, reg_to_map);
+	    }
+	  else
+	    reg_to_map = gen_rtx (SUBREG, arriving_mode, target, 0);
+	}
       else
 	reg_to_map = target;