Prevent out-of-bounds array access in reload.

PR rtl-optimization/18877
* reload.c (decompose) <case REG, case SUBREG>: Handle pseudo reg
number in val.start.

From-SVN: r98938

gcc/ChangeLog

+2005-04-28  Martin Koegler <mkoegler@auto.tuwien.ac.at>
+
+	PR rtl-optimization/18877
+	* reload.c (decompose) <case REG, case SUBREG>: Handle pseudo reg
+	number in val.start.
+
 2005-04-28  David Edelsohn  <edelsohn@gnu.org>
 
 	PR target/20813

gcc/reload.c

@@ -2389,7 +2389,7 @@ decompose (rtx x)
     case REG:
       val.reg_flag = 1;
       val.start = true_regnum (x);
-      if (val.start < 0)
+      if (val.start < 0 || val.start >= FIRST_PSEUDO_REGISTER)
 	{
 	  /* A pseudo with no hard reg.  */
 	  val.start = REGNO (x);
@@ -2406,7 +2406,7 @@ decompose (rtx x)
 	return decompose (SUBREG_REG (x));
       val.reg_flag = 1;
       val.start = true_regnum (x);
-      if (val.start < 0)
+      if (val.start < 0 || val.start >= FIRST_PSEUDO_REGISTER)
 	return decompose (SUBREG_REG (x));
       else
 	/* A hard reg.  */