target/rx: Use cpu_psw_z as temp in flags computation

Since PSW_Z = PSW_S, we can move that assignment to the end
and use PSW_Z as a temporary while computing PSW_O.
Use tcg_constant_i32 instead of tcg_const_i32.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
diff --git a/target/rx/translate.c b/target/rx/translate.c
index 998e6e0..c47aa26 100644
--- a/target/rx/translate.c
+++ b/target/rx/translate.c
@@ -967,14 +967,13 @@
 /* ret = arg1 + arg2 + psw_c */
 static void rx_adc(TCGv ret, TCGv arg1, TCGv arg2)
 {
-    TCGv z;
-    z = tcg_const_i32(0);
+    TCGv z = tcg_constant_i32(0);
     tcg_gen_add2_i32(cpu_psw_s, cpu_psw_c, arg1, z, cpu_psw_c, z);
     tcg_gen_add2_i32(cpu_psw_s, cpu_psw_c, cpu_psw_s, cpu_psw_c, arg2, z);
-    tcg_gen_mov_i32(cpu_psw_z, cpu_psw_s);
     tcg_gen_xor_i32(cpu_psw_o, cpu_psw_s, arg1);
-    tcg_gen_xor_i32(z, arg1, arg2);
-    tcg_gen_andc_i32(cpu_psw_o, cpu_psw_o, z);
+    tcg_gen_xor_i32(cpu_psw_z, arg1, arg2);
+    tcg_gen_andc_i32(cpu_psw_o, cpu_psw_o, cpu_psw_z);
+    tcg_gen_mov_i32(cpu_psw_z, cpu_psw_s);
     tcg_gen_mov_i32(ret, cpu_psw_s);
 }
 
@@ -1006,13 +1005,12 @@
 /* ret = arg1 + arg2 */
 static void rx_add(TCGv ret, TCGv arg1, TCGv arg2)
 {
-    TCGv z;
-    z = tcg_const_i32(0);
+    TCGv z = tcg_constant_i32(0);
     tcg_gen_add2_i32(cpu_psw_s, cpu_psw_c, arg1, z, arg2, z);
-    tcg_gen_mov_i32(cpu_psw_z, cpu_psw_s);
     tcg_gen_xor_i32(cpu_psw_o, cpu_psw_s, arg1);
-    tcg_gen_xor_i32(z, arg1, arg2);
-    tcg_gen_andc_i32(cpu_psw_o, cpu_psw_o, z);
+    tcg_gen_xor_i32(cpu_psw_z, arg1, arg2);
+    tcg_gen_andc_i32(cpu_psw_o, cpu_psw_o, cpu_psw_z);
+    tcg_gen_mov_i32(cpu_psw_z, cpu_psw_s);
     tcg_gen_mov_i32(ret, cpu_psw_s);
 }
 
@@ -1042,23 +1040,23 @@
 /* ret = arg1 - arg2 */
 static void rx_sub(TCGv ret, TCGv arg1, TCGv arg2)
 {
-    TCGv temp;
     tcg_gen_sub_i32(cpu_psw_s, arg1, arg2);
-    tcg_gen_mov_i32(cpu_psw_z, cpu_psw_s);
     tcg_gen_setcond_i32(TCG_COND_GEU, cpu_psw_c, arg1, arg2);
     tcg_gen_xor_i32(cpu_psw_o, cpu_psw_s, arg1);
-    temp = tcg_temp_new_i32();
-    tcg_gen_xor_i32(temp, arg1, arg2);
-    tcg_gen_and_i32(cpu_psw_o, cpu_psw_o, temp);
+    tcg_gen_xor_i32(cpu_psw_z, arg1, arg2);
+    tcg_gen_and_i32(cpu_psw_o, cpu_psw_o, cpu_psw_z);
+    tcg_gen_mov_i32(cpu_psw_z, cpu_psw_s);
     /* CMP not required return */
     if (ret) {
         tcg_gen_mov_i32(ret, cpu_psw_s);
     }
 }
+
 static void rx_cmp(TCGv dummy, TCGv arg1, TCGv arg2)
 {
     rx_sub(NULL, arg1, arg2);
 }
+
 /* ret = arg1 - arg2 - !psw_c */
 /* -> ret = arg1 + ~arg2 + psw_c */
 static void rx_sbb(TCGv ret, TCGv arg1, TCGv arg2)