aarch64.c (aarch64_register_move_cost): Correct cost of moving from/to the…

aarch64.c (aarch64_register_move_cost): Correct cost of moving from/to the STACK_REG register class.

2014-01-15  Andrew Pinski  <apinski@cavium.com>

	* config/aarch64/aarch64.c (aarch64_register_move_cost): Correct cost
	of moving from/to the STACK_REG register class.

From-SVN: r206649

gcc/ChangeLog

+2014-01-15  Andrew Pinski  <apinski@cavium.com>
+
+	* config/aarch64/aarch64.c (aarch64_register_move_cost): Correct cost
+	of moving from/to the STACK_REG register class.
+
 2014-01-15  Richard Henderson <rth@redhat.com>
 
 	PR debug/54694

gcc/config/aarch64/aarch64.c

@@ -4870,6 +4870,16 @@ aarch64_register_move_cost (enum machine_mode mode ATTRIBUTE_UNUSED,
   const struct cpu_regmove_cost *regmove_cost
     = aarch64_tune_params->regmove_cost;
 
+  /* Moving between GPR and stack cost is the same as GP2GP.  */
+  if ((from == GENERAL_REGS && to == STACK_REG)
+      || (to == GENERAL_REGS && from == STACK_REG))
+    return regmove_cost->GP2GP;
+
+  /* To/From the stack register, we move via the gprs.  */
+  if (to == STACK_REG || from == STACK_REG)
+    return aarch64_register_move_cost (mode, from, GENERAL_REGS)
+            + aarch64_register_move_cost (mode, GENERAL_REGS, to);
+
   if (from == GENERAL_REGS && to == GENERAL_REGS)
     return regmove_cost->GP2GP;
   else if (from == GENERAL_REGS)