py: Improve freeing of emitters in mp_compile.

There can be multiple emitters allocated during compile (eg byte code
and native).

py/compile.c

@@ -3154,11 +3154,28 @@ mp_obj_t mp_compile(mp_parse_node_t pn, qstr source_file, bool is_repl) {
         }
     }
 
-    bool had_error = comp->had_error;
-    if (comp->emit_method_table->free != NULL) {
-        comp->emit_method_table->free(comp->emit);
+    // free the emitters
+#if !MICROPY_EMIT_CPYTHON
+    if (emit_bc != NULL) {
+        emit_bc_free(emit_bc);
     }
-    m_del_obj(compiler_t, comp);
+#if MICROPY_EMIT_NATIVE
+    if (emit_native != NULL) {
+#if MICROPY_EMIT_X64
+        emit_native_x64_free(emit_native);
+#elif MICROPY_EMIT_THUMB
+        emit_native_thumb_free(emit_native);
+#endif
+    }
+#endif
+#if MICROPY_EMIT_INLINE_THUMB
+    if (emit_inline_thumb != NULL) {
+        emit_inline_thumb_free(emit_inline_thumb);
+    }
+#endif
+#endif // !MICROPY_EMIT_CPYTHON
+
+    // free the scopes
     uint unique_code_id = module_scope->unique_code_id;
     for (scope_t *s = module_scope; s;) {
         scope_t *next = s->next;
@@ -3166,13 +3183,17 @@ mp_obj_t mp_compile(mp_parse_node_t pn, qstr source_file, bool is_repl) {
         s = next;
     }
 
+    // free the compiler
+    bool had_error = comp->had_error;
+    m_del_obj(compiler_t, comp);
+
     if (had_error) {
         // TODO return a proper error message
         return mp_const_none;
     } else {
 #if MICROPY_EMIT_CPYTHON
         // can't create code, so just return true
-        (void)unique_code_id; // to suppress warning that module_scope is unused
+        (void)unique_code_id; // to suppress warning that unique_code_id is unused
         return mp_const_true;
 #else
         // return function that executes the outer module

py/emit.h

@@ -17,8 +17,6 @@ typedef enum {
 typedef struct _emit_t emit_t;
 
 typedef struct _emit_method_table_t {
-    void (*free)(emit_t *emit);
-
     void (*set_native_types)(emit_t *emit, bool do_native_types);
     void (*start_pass)(emit_t *emit, pass_kind_t pass, scope_t *scope);
     void (*end_pass)(emit_t *emit);
@@ -120,12 +118,16 @@ extern const emit_method_table_t emit_native_x64_method_table;
 extern const emit_method_table_t emit_native_thumb_method_table;
 
 emit_t *emit_pass1_new(qstr qstr___class__);
-void emit_pass1_free(emit_t *emit);
 emit_t *emit_cpython_new(uint max_num_labels);
 emit_t *emit_bc_new(uint max_num_labels);
 emit_t *emit_native_x64_new(uint max_num_labels);
 emit_t *emit_native_thumb_new(uint max_num_labels);
 
+void emit_pass1_free(emit_t *emit);
+void emit_bc_free(emit_t *emit);
+void emit_native_x64_free(emit_t *emit);
+void emit_native_thumb_free(emit_t *emit);
+
 typedef struct _emit_inline_asm_t emit_inline_asm_t;
 
 typedef struct _emit_inline_asm_method_table_t {
@@ -139,3 +141,5 @@ typedef struct _emit_inline_asm_method_table_t {
 extern const emit_inline_asm_method_table_t emit_inline_thumb_method_table;
 
 emit_inline_asm_t *emit_inline_thumb_new(uint max_num_labels);
+void emit_inline_thumb_free(emit_inline_asm_t *emit);
+

py/emitbc.c

@@ -43,7 +43,7 @@ emit_t *emit_bc_new(uint max_num_labels) {
     return emit;
 }
 
-static void emit_bc_free(emit_t *emit) {
+void emit_bc_free(emit_t *emit) {
     m_del(uint, emit->label_offsets, emit->max_num_labels);
     m_del_obj(emit_t, emit);
 }
@@ -756,8 +756,6 @@ static void emit_bc_yield_from(emit_t *emit) {
 }
 
 const emit_method_table_t emit_bc_method_table = {
-    emit_bc_free,
-
     emit_bc_set_native_types,
     emit_bc_start_pass,
     emit_bc_end_pass,

py/emitcpy.c

@@ -796,8 +796,6 @@ static void emit_cpy_yield_from(emit_t *emit) {
 }
 
 const emit_method_table_t emit_cpython_method_table = {
-    NULL,
-
     emit_cpy_set_native_types,
     emit_cpy_start_pass,
     emit_cpy_end_pass,

py/emitinlinethumb.c

@@ -20,13 +20,13 @@
 struct _emit_inline_asm_t {
     int pass;
     scope_t *scope;
-    int max_num_labels;
+    uint max_num_labels;
     qstr *label_lookup;
     asm_thumb_t *as;
 };
 
 emit_inline_asm_t *emit_inline_thumb_new(uint max_num_labels) {
-    emit_inline_asm_t *emit = m_new(emit_inline_asm_t, 1);
+    emit_inline_asm_t *emit = m_new_obj(emit_inline_asm_t);
     emit->max_num_labels = max_num_labels;
     emit->label_lookup = m_new(qstr, max_num_labels);
     memset(emit->label_lookup, 0, emit->max_num_labels * sizeof(qstr));
@@ -34,6 +34,12 @@ emit_inline_asm_t *emit_inline_thumb_new(uint max_num_labels) {
     return emit;
 }
 
+void emit_inline_thumb_free(emit_inline_asm_t *emit) {
+    m_del(qstr, emit->label_lookup, emit->max_num_labels);
+    asm_thumb_free(emit->as, false);
+    m_del_obj(emit_inline_asm_t, emit);
+}
+
 static void emit_inline_thumb_start_pass(emit_inline_asm_t *emit, pass_kind_t pass, scope_t *scope) {
     emit->pass = pass;
     emit->scope = scope;

py/emitnative.c

@@ -146,7 +146,7 @@ emit_t *EXPORT_FUN(new)(uint max_num_labels) {
     return emit;
 }
 
-static void emit_native_free(emit_t *emit) {
+void EXPORT_FUN(free)(emit_t *emit) {
 #if N_X64
     asm_x64_free(emit->as, false);
 #elif N_THUMB
@@ -1235,8 +1235,6 @@ static void emit_native_yield_from(emit_t *emit) {
 }
 
 const emit_method_table_t EXPORT_FUN(method_table) = {
-    emit_native_free,
-
     emit_native_set_viper_types,
     emit_native_start_pass,
     emit_native_end_pass,

py/emitpass1.c

@@ -97,8 +97,6 @@ static void emit_pass1_delete_id(emit_t *emit, qstr qstr) {
 }
 
 const emit_method_table_t emit_pass1_method_table = {
-    emit_pass1_free,
-
     (void*)emit_pass1_dummy,
     emit_pass1_start_pass,
     emit_pass1_end_pass,