reload.c (find_reloads): Use a hard reg destination as reload reg for an input…

reload.c (find_reloads): Use a hard reg destination as reload reg for an input reload of the source.

        * reload.c (find_reloads): Use a hard reg destination as reload reg
        for an input reload of the source.

From-SVN: r48822

gcc/ChangeLog

+2002-01-13  Richard Henderson  <rth@redhat.com>
+
+	* reload.c (find_reloads): Use a hard reg destination as reload reg
+	for an input reload of the source.
+
 2002-01-13  Gerald Pfeifer  <pfeifer@dbai.tuwien.ac.at>
 
 	* doc/install.texi (Binaries): Make link to ftp.writtenword.com

gcc/reload.c

@@ -4241,6 +4241,23 @@ find_reloads (insn, replace, ind_levels, live_known, reload_reg_p)
       rld[i].nregs = CLASS_MAX_NREGS (rld[i].class, rld[i].mode);
     }
 
+  /* Special case a simple move with an input reload and a
+     destination of a hard reg, if the hard reg is ok, use it.  */
+  for (i = 0; i < n_reloads; i++)
+    if (rld[i].when_needed == RELOAD_FOR_INPUT
+	&& GET_CODE (PATTERN (insn)) == SET
+ 	&& GET_CODE (SET_DEST (PATTERN (insn))) == REG
+ 	&& SET_SRC (PATTERN (insn)) == rld[i].in)
+      {
+ 	rtx dest = SET_DEST (PATTERN (insn));
+	unsigned int regno = REGNO (dest);
+
+ 	if (regno < FIRST_PSEUDO_REGISTER
+ 	    && TEST_HARD_REG_BIT (reg_class_contents[rld[i].class], regno)
+ 	    && HARD_REGNO_MODE_OK (regno, rld[i].mode))
+ 	  rld[i].reg_rtx = dest;
+      }
+
   return retval;
 }