[#18] Move Z80-specific register handlers to the root.

z80.h

@@ -375,6 +375,16 @@ class root {
         unreachable("Unknown register.");
     }
 
+    fast_u16 on_get_regp(regp rp, iregp irp) {
+        return rp == regp::hl ? self().on_get_iregp(irp) :
+                                self().on_get_regp(rp);
+    }
+
+    void on_set_regp(regp rp, iregp irp, fast_u16 nn) {
+        return rp == regp::hl ? self().on_set_iregp(irp, nn) :
+                                self().on_set_regp(rp, nn);
+    }
+
     fast_u16 on_get_regp2(regp2 rp) {
         switch(rp) {
         case regp2::bc: return self().on_get_bc();
@@ -395,6 +405,16 @@ class root {
         unreachable("Unknown register.");
     }
 
+    fast_u16 on_get_regp2(regp2 rp, iregp irp) {
+        return rp == regp2::hl ? self().on_get_iregp(irp) :
+                                 self().on_get_regp2(rp);
+    }
+
+    void on_set_regp2(regp2 rp, iregp irp, fast_u16 nn) {
+        return rp == regp2::hl ? self().on_set_iregp(irp, nn) :
+                                 self().on_set_regp2(rp, nn);
+    }
+
     // No dummy implementations for the following handlers as
     // being forgotten to be implemented, they would lead to
     // problems that are hard to diagnose.
@@ -2936,26 +2956,6 @@ class z80_executor : public internals::executor_base<B> {
                                  base::on_set_reg(r, irp, n);
     }
 
-    fast_u16 on_get_regp(regp rp, iregp irp) {
-        return rp == regp::hl ? self().on_get_iregp(irp) :
-                                base::on_get_regp(rp);
-    }
-
-    void on_set_regp(regp rp, iregp irp, fast_u16 nn) {
-        return rp == regp::hl ? self().on_set_iregp(irp, nn) :
-                                base::on_set_regp(rp, nn);
-    }
-
-    fast_u16 on_get_regp2(regp2 rp, iregp irp) {
-        return rp == regp2::hl ? self().on_get_iregp(irp) :
-                                 base::on_get_regp2(rp);
-    }
-
-    void on_set_regp2(regp2 rp, iregp irp, fast_u16 nn) {
-        return rp == regp2::hl ? self().on_set_iregp(irp, nn) :
-                                 base::on_set_regp2(rp, nn);
-    }
-
     bool check_condition(condition cc) {
         // TODO: Would it make sense to store flags in a different order?
         auto n = static_cast<unsigned>(cc);