1 files changed, 149 insertions, 0 deletions
diff --git a/circuitpython/py/gc_long_lived.c b/circuitpython/py/gc_long_lived.c
new file mode 100644
index 0000000..647c4f7
--- /dev/null
+++ b/circuitpython/py/gc_long_lived.c
@@ -0,0 +1,149 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2018 Scott Shawcroft for Adafruit Industries LLC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "py/emitglue.h"
+#include "py/gc_long_lived.h"
+#include "py/gc.h"
+#include "py/mpstate.h"
+
+mp_obj_fun_bc_t *make_fun_bc_long_lived(mp_obj_fun_bc_t *fun_bc, uint8_t max_depth) {
+    #ifndef MICROPY_ENABLE_GC
+    return fun_bc;
+    #endif
+    if (fun_bc == NULL || MP_OBJ_FROM_PTR(fun_bc) == mp_const_none || max_depth == 0) {
+        return fun_bc;
+    }
+    fun_bc->bytecode = gc_make_long_lived((byte *)fun_bc->bytecode);
+    fun_bc->globals = make_dict_long_lived(fun_bc->globals, max_depth - 1);
+    for (uint32_t i = 0; i < gc_nbytes(fun_bc->const_table) / sizeof(mp_obj_t); i++) {
+        // Skip things that aren't allocated on the heap (and hence have zero bytes.)
+        if (gc_nbytes(MP_OBJ_TO_PTR(fun_bc->const_table[i])) == 0) {
+            continue;
+        }
+        // Try to detect raw code.
+        mp_raw_code_t *raw_code = MP_OBJ_TO_PTR(fun_bc->const_table[i]);
+        if (raw_code->kind == MP_CODE_BYTECODE) {
+            raw_code->fun_data = gc_make_long_lived((byte *)raw_code->fun_data);
+            raw_code->const_table = gc_make_long_lived((byte *)raw_code->const_table);
+        }
+        ((mp_uint_t *)fun_bc->const_table)[i] = (mp_uint_t)make_obj_long_lived(
+            (mp_obj_t)fun_bc->const_table[i], max_depth - 1);
+
+    }
+    fun_bc->const_table = gc_make_long_lived((mp_uint_t *)fun_bc->const_table);
+    // extra_args stores keyword only argument default values.
+    size_t words = gc_nbytes(fun_bc) / sizeof(mp_uint_t *);
+    // Functions (mp_obj_fun_bc_t) have four pointers (base, globals, bytecode and const_table)
+    // before the variable length extra_args so remove them from the length.
+    for (size_t i = 0; i < words - 4; i++) {
+        if (MP_OBJ_TO_PTR(fun_bc->extra_args[i]) == NULL) {
+            continue;
+        }
+        if (mp_obj_is_type(fun_bc->extra_args[i], &mp_type_dict)) {
+            fun_bc->extra_args[i] = MP_OBJ_FROM_PTR(make_dict_long_lived(MP_OBJ_TO_PTR(fun_bc->extra_args[i]), max_depth - 1));
+        } else {
+            fun_bc->extra_args[i] = make_obj_long_lived(fun_bc->extra_args[i], max_depth - 1);
+        }
+
+    }
+    return gc_make_long_lived(fun_bc);
+}
+
+mp_obj_property_t *make_property_long_lived(mp_obj_property_t *prop, uint8_t max_depth) {
+    #ifndef MICROPY_ENABLE_GC
+    return prop;
+    #endif
+    if (max_depth == 0) {
+        return prop;
+    }
+    prop->proxy[0] = make_obj_long_lived(prop->proxy[0], max_depth - 1);
+    prop->proxy[1] = make_obj_long_lived(prop->proxy[1], max_depth - 1);
+    prop->proxy[2] = make_obj_long_lived(prop->proxy[2], max_depth - 1);
+    return gc_make_long_lived(prop);
+}
+
+mp_obj_dict_t *make_dict_long_lived(mp_obj_dict_t *dict, uint8_t max_depth) {
+    #ifndef MICROPY_ENABLE_GC
+    return dict;
+    #endif
+    if (dict == NULL || max_depth == 0 || dict == &MP_STATE_VM(dict_main) || dict->map.is_fixed) {
+        return dict;
+    }
+    // Don't recurse unnecessarily. Return immediately if we've already seen this dict.
+    if (dict->map.scanning) {
+        return dict;
+    }
+    // Mark that we're processing this dict.
+    dict->map.scanning = 1;
+
+    // Update all of the references first so that we reduce the chance of references to the old
+    // copies.
+    dict->map.table = gc_make_long_lived(dict->map.table);
+    for (size_t i = 0; i < dict->map.alloc; i++) {
+        if (mp_map_slot_is_filled(&dict->map, i)) {
+            mp_obj_t value = dict->map.table[i].value;
+            dict->map.table[i].value = make_obj_long_lived(value, max_depth - 1);
+        }
+    }
+    dict = gc_make_long_lived(dict);
+    // Done recursing through this dict.
+    dict->map.scanning = 0;
+    return dict;
+}
+
+mp_obj_str_t *make_str_long_lived(mp_obj_str_t *str) {
+    str->data = gc_make_long_lived((byte *)str->data);
+    return gc_make_long_lived(str);
+}
+
+mp_obj_t make_obj_long_lived(mp_obj_t obj, uint8_t max_depth) {
+    #ifndef MICROPY_ENABLE_GC
+    return obj;
+    #endif
+    if (MP_OBJ_TO_PTR(obj) == NULL) {
+        return obj;
+    }
+    // If not in the GC pool, do nothing. This can happen (at least) when
+    // there are frozen mp_type_bytes objects in ROM.
+    if (!VERIFY_PTR((void *)obj)) {
+        return obj;
+    }
+    if (mp_obj_is_type(obj, &mp_type_fun_bc)) {
+        mp_obj_fun_bc_t *fun_bc = MP_OBJ_TO_PTR(obj);
+        return MP_OBJ_FROM_PTR(make_fun_bc_long_lived(fun_bc, max_depth));
+    } else if (mp_obj_is_type(obj, &mp_type_property)) {
+        mp_obj_property_t *prop = MP_OBJ_TO_PTR(obj);
+        return MP_OBJ_FROM_PTR(make_property_long_lived(prop, max_depth));
+    } else if (mp_obj_is_type(obj, &mp_type_str) || mp_obj_is_type(obj, &mp_type_bytes)) {
+        mp_obj_str_t *str = MP_OBJ_TO_PTR(obj);
+        return MP_OBJ_FROM_PTR(make_str_long_lived(str));
+    } else if (mp_obj_is_type(obj, &mp_type_type)) {
+        // Types are already long lived during creation.
+        return obj;
+    } else {
+        return MP_OBJ_FROM_PTR(gc_make_long_lived(MP_OBJ_TO_PTR(obj)));
+    }
+}