py/emit: Combine fast and deref into one function for load/store/delete.

Reduces code size by:

   bare-arm:   -16
minimal x86:  -208
   unix x64:  -408
unix nanbox:  -248
      stm32:   -12
     cc3200:   -24
    esp8266:   -96
      esp32:   -44

5 files changed, 61 insertions, 68 deletions

diff --git a/py/compile.c b/py/compile.c
index c2dd914f0..4d985a07f 100644
--- a/py/compile.c
+++ b/py/compile.c
@@ -65,7 +65,7 @@ typedef enum {
 // we need a method table to do the lookup for the emitter functions
 #define EMIT(fun) (comp->emit_method_table->fun(comp->emit))
 #define EMIT_ARG(fun, ...) (comp->emit_method_table->fun(comp->emit, __VA_ARGS__))
-#define EMIT_LOAD_FAST(qst, local_num) (comp->emit_method_table->load_id.fast(comp->emit, qst, local_num))
+#define EMIT_LOAD_FAST(qst, local_num) (comp->emit_method_table->load_id.local(comp->emit, qst, local_num, MP_EMIT_IDOP_LOCAL_FAST))
 #define EMIT_LOAD_GLOBAL(qst) (comp->emit_method_table->load_id.global(comp->emit, qst))
 
 #else
@@ -73,7 +73,7 @@ typedef enum {
 // if we only have the bytecode emitter enabled then we can do a direct call to the functions
 #define EMIT(fun) (mp_emit_bc_##fun(comp->emit))
 #define EMIT_ARG(fun, ...) (mp_emit_bc_##fun(comp->emit, __VA_ARGS__))
-#define EMIT_LOAD_FAST(qst, local_num) (mp_emit_bc_load_fast(comp->emit, qst, local_num))
+#define EMIT_LOAD_FAST(qst, local_num) (mp_emit_bc_load_local(comp->emit, qst, local_num, MP_EMIT_IDOP_LOCAL_FAST))
 #define EMIT_LOAD_GLOBAL(qst) (mp_emit_bc_load_global(comp->emit, qst))
 
 #endif
diff --git a/py/emit.h b/py/emit.h
index 270a40633..5fe3c3d1f 100644
--- a/py/emit.h
+++ b/py/emit.h
@@ -55,11 +55,14 @@ typedef enum {
 #define MP_EMIT_NATIVE_TYPE_RETURN (1)
 #define MP_EMIT_NATIVE_TYPE_ARG    (2)
 
+// Kind for emit_id_ops->local()
+#define MP_EMIT_IDOP_LOCAL_FAST (0)
+#define MP_EMIT_IDOP_LOCAL_DEREF (1)
+
 typedef struct _emit_t emit_t;
 
 typedef struct _mp_emit_method_table_id_ops_t {
-    void (*fast)(emit_t *emit, qstr qst, mp_uint_t local_num);
-    void (*deref)(emit_t *emit, qstr qst, mp_uint_t local_num);
+    void (*local)(emit_t *emit, qstr qst, mp_uint_t local_num, int kind);
     void (*name)(emit_t *emit, qstr qst);
     void (*global)(emit_t *emit, qstr qst);
 } mp_emit_method_table_id_ops_t;
@@ -180,16 +183,13 @@ bool mp_emit_bc_last_emit_was_return_value(emit_t *emit);
 void mp_emit_bc_adjust_stack_size(emit_t *emit, mp_int_t delta);
 void mp_emit_bc_set_source_line(emit_t *emit, mp_uint_t line);
 
-void mp_emit_bc_load_fast(emit_t *emit, qstr qst, mp_uint_t local_num);
-void mp_emit_bc_load_deref(emit_t *emit, qstr qst, mp_uint_t local_num);
+void mp_emit_bc_load_local(emit_t *emit, qstr qst, mp_uint_t local_num, int kind);
 void mp_emit_bc_load_name(emit_t *emit, qstr qst);
 void mp_emit_bc_load_global(emit_t *emit, qstr qst);
-void mp_emit_bc_store_fast(emit_t *emit, qstr qst, mp_uint_t local_num);
-void mp_emit_bc_store_deref(emit_t *emit, qstr qst, mp_uint_t local_num);
+void mp_emit_bc_store_local(emit_t *emit, qstr qst, mp_uint_t local_num, int kind);
 void mp_emit_bc_store_name(emit_t *emit, qstr qst);
 void mp_emit_bc_store_global(emit_t *emit, qstr qst);
-void mp_emit_bc_delete_fast(emit_t *emit, qstr qst, mp_uint_t local_num);
-void mp_emit_bc_delete_deref(emit_t *emit, qstr qst, mp_uint_t local_num);
+void mp_emit_bc_delete_local(emit_t *emit, qstr qst, mp_uint_t local_num, int kind);
 void mp_emit_bc_delete_name(emit_t *emit, qstr qst);
 void mp_emit_bc_delete_global(emit_t *emit, qstr qst);
 
diff --git a/py/emitbc.c b/py/emitbc.c
index b1b61ba67..28d32d4ea 100644
--- a/py/emitbc.c
+++ b/py/emitbc.c
@@ -556,22 +556,18 @@ void mp_emit_bc_load_null(emit_t *emit) {
     emit_write_bytecode_byte(emit, MP_BC_LOAD_NULL);
 }
 
-void mp_emit_bc_load_fast(emit_t *emit, qstr qst, mp_uint_t local_num) {
+void mp_emit_bc_load_local(emit_t *emit, qstr qst, mp_uint_t local_num, int kind) {
+    MP_STATIC_ASSERT(MP_BC_LOAD_FAST_N + MP_EMIT_IDOP_LOCAL_FAST == MP_BC_LOAD_FAST_N);
+    MP_STATIC_ASSERT(MP_BC_LOAD_FAST_N + MP_EMIT_IDOP_LOCAL_DEREF == MP_BC_LOAD_DEREF);
     (void)qst;
     emit_bc_pre(emit, 1);
-    if (local_num <= 15) {
+    if (kind == MP_EMIT_IDOP_LOCAL_FAST && local_num <= 15) {
         emit_write_bytecode_byte(emit, MP_BC_LOAD_FAST_MULTI + local_num);
     } else {
-        emit_write_bytecode_byte_uint(emit, MP_BC_LOAD_FAST_N, local_num);
+        emit_write_bytecode_byte_uint(emit, MP_BC_LOAD_FAST_N + kind, local_num);
     }
 }
 
-void mp_emit_bc_load_deref(emit_t *emit, qstr qst, mp_uint_t local_num) {
-    (void)qst;
-    emit_bc_pre(emit, 1);
-    emit_write_bytecode_byte_uint(emit, MP_BC_LOAD_DEREF, local_num);
-}
-
 void mp_emit_bc_load_name(emit_t *emit, qstr qst) {
     (void)qst;
     emit_bc_pre(emit, 1);
@@ -613,22 +609,18 @@ void mp_emit_bc_load_subscr(emit_t *emit) {
     emit_write_bytecode_byte(emit, MP_BC_LOAD_SUBSCR);
 }
 
-void mp_emit_bc_store_fast(emit_t *emit, qstr qst, mp_uint_t local_num) {
+void mp_emit_bc_store_local(emit_t *emit, qstr qst, mp_uint_t local_num, int kind) {
+    MP_STATIC_ASSERT(MP_BC_STORE_FAST_N + MP_EMIT_IDOP_LOCAL_FAST == MP_BC_STORE_FAST_N);
+    MP_STATIC_ASSERT(MP_BC_STORE_FAST_N + MP_EMIT_IDOP_LOCAL_DEREF == MP_BC_STORE_DEREF);
     (void)qst;
     emit_bc_pre(emit, -1);
-    if (local_num <= 15) {
+    if (kind == MP_EMIT_IDOP_LOCAL_FAST && local_num <= 15) {
         emit_write_bytecode_byte(emit, MP_BC_STORE_FAST_MULTI + local_num);
     } else {
-        emit_write_bytecode_byte_uint(emit, MP_BC_STORE_FAST_N, local_num);
+        emit_write_bytecode_byte_uint(emit, MP_BC_STORE_FAST_N + kind, local_num);
     }
 }
 
-void mp_emit_bc_store_deref(emit_t *emit, qstr qst, mp_uint_t local_num) {
-    (void)qst;
-    emit_bc_pre(emit, -1);
-    emit_write_bytecode_byte_uint(emit, MP_BC_STORE_DEREF, local_num);
-}
-
 void mp_emit_bc_store_name(emit_t *emit, qstr qst) {
     emit_bc_pre(emit, -1);
     emit_write_bytecode_byte_qstr(emit, MP_BC_STORE_NAME, qst);
@@ -652,14 +644,11 @@ void mp_emit_bc_store_subscr(emit_t *emit) {
     emit_write_bytecode_byte(emit, MP_BC_STORE_SUBSCR);
 }
 
-void mp_emit_bc_delete_fast(emit_t *emit, qstr qst, mp_uint_t local_num) {
-    (void)qst;
-    emit_write_bytecode_byte_uint(emit, MP_BC_DELETE_FAST, local_num);
-}
-
-void mp_emit_bc_delete_deref(emit_t *emit, qstr qst, mp_uint_t local_num) {
+void mp_emit_bc_delete_local(emit_t *emit, qstr qst, mp_uint_t local_num, int kind) {
+    MP_STATIC_ASSERT(MP_BC_DELETE_FAST + MP_EMIT_IDOP_LOCAL_FAST == MP_BC_DELETE_FAST);
+    MP_STATIC_ASSERT(MP_BC_DELETE_FAST + MP_EMIT_IDOP_LOCAL_DEREF == MP_BC_DELETE_DEREF);
     (void)qst;
-    emit_write_bytecode_byte_uint(emit, MP_BC_DELETE_DEREF, local_num);
+    emit_write_bytecode_byte_uint(emit, MP_BC_DELETE_FAST + kind, local_num);
 }
 
 void mp_emit_bc_delete_name(emit_t *emit, qstr qst) {
@@ -972,20 +961,17 @@ const emit_method_table_t emit_bc_method_table = {
     mp_emit_bc_set_source_line,
 
     {
-        mp_emit_bc_load_fast,
-        mp_emit_bc_load_deref,
+        mp_emit_bc_load_local,
         mp_emit_bc_load_name,
         mp_emit_bc_load_global,
     },
     {
-        mp_emit_bc_store_fast,
-        mp_emit_bc_store_deref,
+        mp_emit_bc_store_local,
         mp_emit_bc_store_name,
         mp_emit_bc_store_global,
     },
     {
-        mp_emit_bc_delete_fast,
-        mp_emit_bc_delete_deref,
+        mp_emit_bc_delete_local,
         mp_emit_bc_delete_name,
         mp_emit_bc_delete_global,
     },
@@ -1056,22 +1042,19 @@ const emit_method_table_t emit_bc_method_table = {
 };
 #else
 const mp_emit_method_table_id_ops_t mp_emit_bc_method_table_load_id_ops = {
-    mp_emit_bc_load_fast,
-    mp_emit_bc_load_deref,
+    mp_emit_bc_load_local,
     mp_emit_bc_load_name,
     mp_emit_bc_load_global,
 };
 
 const mp_emit_method_table_id_ops_t mp_emit_bc_method_table_store_id_ops = {
-    mp_emit_bc_store_fast,
-    mp_emit_bc_store_deref,
+    mp_emit_bc_store_local,
     mp_emit_bc_store_name,
     mp_emit_bc_store_global,
 };
 
 const mp_emit_method_table_id_ops_t mp_emit_bc_method_table_delete_id_ops = {
-    mp_emit_bc_delete_fast,
-    mp_emit_bc_delete_deref,
+    mp_emit_bc_delete_local,
     mp_emit_bc_delete_name,
     mp_emit_bc_delete_global,
 };
diff --git a/py/emitcommon.c b/py/emitcommon.c
index 07b1dbb4c..47fd41ef2 100644
--- a/py/emitcommon.c
+++ b/py/emitcommon.c
@@ -67,10 +67,10 @@ void mp_emit_common_id_op(emit_t *emit, const mp_emit_method_table_id_ops_t *emi
     } else if (id->kind == ID_INFO_KIND_GLOBAL_EXPLICIT) {
         emit_method_table->global(emit, qst);
     } else if (id->kind == ID_INFO_KIND_LOCAL) {
-        emit_method_table->fast(emit, qst, id->local_num);
+        emit_method_table->local(emit, qst, id->local_num, MP_EMIT_IDOP_LOCAL_FAST);
     } else {
         assert(id->kind == ID_INFO_KIND_CELL || id->kind == ID_INFO_KIND_FREE);
-        emit_method_table->deref(emit, qst, id->local_num);
+        emit_method_table->local(emit, qst, id->local_num, MP_EMIT_IDOP_LOCAL_DEREF);
     }
 }
 
diff --git a/py/emitnative.c b/py/emitnative.c
index 7e017ba39..9e16ef4bd 100644
--- a/py/emitnative.c
+++ b/py/emitnative.c
@@ -938,6 +938,14 @@ STATIC void emit_native_load_deref(emit_t *emit, qstr qst, mp_uint_t local_num)
     emit_post_push_reg(emit, VTYPE_PYOBJ, REG_RET);
 }
 
+STATIC void emit_native_load_local(emit_t *emit, qstr qst, mp_uint_t local_num, int kind) {
+    if (kind == MP_EMIT_IDOP_LOCAL_FAST) {
+        emit_native_load_fast(emit, qst, local_num);
+    } else {
+        emit_native_load_deref(emit, qst, local_num);
+    }
+}
+
 STATIC void emit_native_load_name(emit_t *emit, qstr qst) {
     DEBUG_printf("load_name(%s)\n", qstr_str(qst));
     emit_native_pre(emit);
@@ -1178,6 +1186,14 @@ STATIC void emit_native_store_deref(emit_t *emit, qstr qst, mp_uint_t local_num)
     emit_post(emit);
 }
 
+STATIC void emit_native_store_local(emit_t *emit, qstr qst, mp_uint_t local_num, int kind) {
+    if (kind == MP_EMIT_IDOP_LOCAL_FAST) {
+        emit_native_store_fast(emit, qst, local_num);
+    } else {
+        emit_native_store_deref(emit, qst, local_num);
+    }
+}
+
 STATIC void emit_native_store_name(emit_t *emit, qstr qst) {
     // mp_store_name, but needs conversion of object (maybe have mp_viper_store_name(obj, type))
     vtype_kind_t vtype;
@@ -1389,19 +1405,16 @@ STATIC void emit_native_store_subscr(emit_t *emit) {
     }
 }
 
-STATIC void emit_native_delete_fast(emit_t *emit, qstr qst, mp_uint_t local_num) {
-    // TODO: This is not compliant implementation. We could use MP_OBJ_SENTINEL
-    // to mark deleted vars but then every var would need to be checked on
-    // each access. Very inefficient, so just set value to None to enable GC.
-    emit_native_load_const_tok(emit, MP_TOKEN_KW_NONE);
-    emit_native_store_fast(emit, qst, local_num);
-}
-
-STATIC void emit_native_delete_deref(emit_t *emit, qstr qst, mp_uint_t local_num) {
-    // TODO implement me!
-    (void)emit;
-    (void)qst;
-    (void)local_num;
+STATIC void emit_native_delete_local(emit_t *emit, qstr qst, mp_uint_t local_num, int kind) {
+    if (kind == MP_EMIT_IDOP_LOCAL_FAST) {
+        // TODO: This is not compliant implementation. We could use MP_OBJ_SENTINEL
+        // to mark deleted vars but then every var would need to be checked on
+        // each access. Very inefficient, so just set value to None to enable GC.
+        emit_native_load_const_tok(emit, MP_TOKEN_KW_NONE);
+        emit_native_store_fast(emit, qst, local_num);
+    } else {
+        // TODO implement me!
+    }
 }
 
 STATIC void emit_native_delete_name(emit_t *emit, qstr qst) {
@@ -2192,20 +2205,17 @@ const emit_method_table_t EXPORT_FUN(method_table) = {
     emit_native_set_source_line,
 
     {
-        emit_native_load_fast,
-        emit_native_load_deref,
+        emit_native_load_local,
         emit_native_load_name,
         emit_native_load_global,
     },
     {
-        emit_native_store_fast,
-        emit_native_store_deref,
+        emit_native_store_local,
         emit_native_store_name,
         emit_native_store_global,
     },
     {
-        emit_native_delete_fast,
-        emit_native_delete_deref,
+        emit_native_delete_local,
         emit_native_delete_name,
         emit_native_delete_global,
     },