[RS6000] Force source of fix_trunc<mode>si2 to reg

	* config/rs6000/rs6000.md (fix_trunc<mode>si2): Force source operand
	to a reg.  Localize vars.

From-SVN: r239011

gcc/ChangeLog

 2016-08-03  Alan Modra  <amodra@gmail.com>
 
+	* config/rs6000/rs6000.md (fix_trunc<mode>si2): Force source operand
+	to a reg.  Localize vars.
+
+2016-08-03  Alan Modra  <amodra@gmail.com>
+
 	* config/rs6000/rs6000.opt: Remove negatives from help strings
 	and comments.
 

gcc/config/rs6000/rs6000.md

@@ -5357,15 +5357,15 @@
 {
   if (!<E500_CONVERT>)
     {
-      rtx tmp, stack;
+      rtx src = force_reg (SFmode, operands[1]);
 
       if (TARGET_STFIWX)
-	emit_insn (gen_fix_trunc<mode>si2_stfiwx (operands[0], operands[1]));
+	emit_insn (gen_fix_trunc<mode>si2_stfiwx (operands[0], src));
       else
 	{
-	  tmp = gen_reg_rtx (DImode);
-	  stack = rs6000_allocate_stack_temp (DImode, true, false);
-	  emit_insn (gen_fix_trunc<mode>si2_internal (operands[0], operands[1],
+	  rtx tmp = gen_reg_rtx (DImode);
+	  rtx stack = rs6000_allocate_stack_temp (DImode, true, false);
+	  emit_insn (gen_fix_trunc<mode>si2_internal (operands[0], src,
 						      tmp, stack));
 	}
       DONE;