re PR target/24954 (ICE: could not split insn)

	PR target/24954
	* config/rs6000/predicated.md (easy_vector_constant_add_self): Use
	explicit sign extension, not a (char) cast.

From-SVN: r107352

gcc/ChangeLog

+2005-11-22  Alan Modra  <amodra@bigpond.net.au>
+
+	PR target/24954
+	* config/rs6000/predicated.md (easy_vector_constant_add_self): Use
+	explicit sign extension, not a (char) cast.
+
 2005-11-22  Ben Elliston  <bje@au.ibm.com>
 
 	* optabs.c: Use SCALAR_FLOAT_MODE_P instead of explicitly testing

gcc/config/rs6000/predicates.md

@@ -317,7 +317,7 @@
 	    (match_test "easy_altivec_constant (op, mode)")))
 {
   rtx last = CONST_VECTOR_ELT (op, GET_MODE_NUNITS (mode) - 1);
-  HOST_WIDE_INT val = (char) (INTVAL (last) & 255);
+  HOST_WIDE_INT val = ((INTVAL (last) & 0xff) ^ 0x7f) - 0x7f;
   return EASY_VECTOR_15_ADD_SELF (val);
 })