(make_extraction): Correct typo in force_to_mode call in previous change.

Return 0 if pos+len out of range of want desired mode.

From-SVN: r11544

diff --git a/gcc/combine.c b/gcc/combine.c
index 7023119..70b9faa 100644 (file)
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -5321,13 +5321,23 @@ make_extraction (mode, inner, pos, pos_rtx, len,
        }
     }
 
-  /* If INNER is not memory, we can always get it into the proper mode. */
+  /* If INNER is not memory, we can always get it into the proper mode.  If we
+     are changing its mode, POS must be a constant and smaller than the size
+     of the new mode.  */
   else if (GET_CODE (inner) != MEM)
-    inner = force_to_mode (inner, wanted_inner_mode,
-                          pos_rtx || len + orig_pos >= HOST_BITS_PER_WIDE_INT
-                          ? GET_MODE_MASK (extraction_mode)
-                          : (((HOST_WIDE_INT) 1 << len) - 1) << orig_pos,
-                          NULL_RTX, 0);
+    {
+      if (GET_MODE (inner) != wanted_inner_mode
+         && (pos_rtx != 0
+             || orig_pos + len > GET_MODE_BITSIZE (wanted_inner_mode)))
+       return 0;
+
+      inner = force_to_mode (inner, wanted_inner_mode,
+                            pos_rtx
+                            || len + orig_pos >= HOST_BITS_PER_WIDE_INT
+                            ? GET_MODE_MASK (wanted_inner_mode)
+                            : (((HOST_WIDE_INT) 1 << len) - 1) << orig_pos,
+                            NULL_RTX, 0);
+    }
 
   /* Adjust mode of POS_RTX, if needed.  If we want a wider mode, we
      have to zero extend.  Otherwise, we can just use a SUBREG.  */