py/persistentcode.c - lite/micropython - Linaro Git Browser

 /*
  * This file is part of the MicroPython project, http://micropython.org/
  *
  * The MIT License (MIT)
  *
  * Copyright (c) 2013-2020 Damien P. George
  *
  * 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 <stdint.h>
 #include <stdio.h>
 #include <string.h>
 #include <assert.h>

 #include "py/reader.h"
 #include "py/nativeglue.h"
 #include "py/persistentcode.h"
 #include "py/bc0.h"
 #include "py/objstr.h"
 #include "py/mpthread.h"

 #if MICROPY_PERSISTENT_CODE_LOAD || MICROPY_PERSISTENT_CODE_SAVE

 #include "py/smallint.h"

 // makeqstrdata.py has a fixed list of qstrs at the start that we can assume
 // are available with know indices on all MicroPython implementations, and
 // avoid needing to duplicate the string data in the .mpy file. This is the
 // last one in that list (anything with a qstr less than or equal to this is
 // assumed to be in the list).
 #define QSTR_LAST_STATIC MP_QSTR_zip

 #if MICROPY_DYNAMIC_COMPILER
 #define MPY_FEATURE_ARCH_DYNAMIC mp_dynamic_compiler.native_arch
 #else
 #define MPY_FEATURE_ARCH_DYNAMIC MPY_FEATURE_ARCH
 #endif

 typedef struct _bytecode_prelude_t {
     uint n_state;
     uint n_exc_stack;
     uint scope_flags;
     uint n_pos_args;
     uint n_kwonly_args;
     uint n_def_pos_args;
     uint code_info_size;
 } bytecode_prelude_t;

 #endif // MICROPY_PERSISTENT_CODE_LOAD || MICROPY_PERSISTENT_CODE_SAVE

 #if MICROPY_PERSISTENT_CODE_LOAD

 #include "py/parsenum.h"

 static int read_byte(mp_reader_t *reader);
 static size_t read_uint(mp_reader_t *reader);

 #if MICROPY_PERSISTENT_CODE_TRACK_FUN_DATA || MICROPY_PERSISTENT_CODE_TRACK_BSS_RODATA

 // An mp_obj_list_t that tracks native text/BSS/rodata to prevent the GC from reclaiming them.
 MP_REGISTER_ROOT_POINTER(mp_obj_t persistent_code_root_pointers);

 static void track_root_pointer(void *ptr) {
     if (MP_STATE_PORT(persistent_code_root_pointers) == MP_OBJ_NULL) {
         MP_STATE_PORT(persistent_code_root_pointers) = mp_obj_new_list(0, NULL);
     }
     mp_obj_list_append(MP_STATE_PORT(persistent_code_root_pointers), MP_OBJ_FROM_PTR(ptr));
 }

 #endif

 #if MICROPY_EMIT_MACHINE_CODE

 typedef struct _reloc_info_t {
     mp_reader_t *reader;
     mp_module_context_t *context;
     uint8_t *rodata;
     uint8_t *bss;
 } reloc_info_t;

 void mp_native_relocate(void *ri_in, uint8_t *text, uintptr_t reloc_text) {
     // Relocate native code
     reloc_info_t *ri = ri_in;
     uint8_t op;
     uintptr_t *addr_to_adjust = NULL;
     while ((op = read_byte(ri->reader)) != 0xff) {
         if (op & 1) {
             // Point to new location to make adjustments
             size_t addr = read_uint(ri->reader);
             if ((addr & 1) == 0) {
                 // Point to somewhere in text
                 addr_to_adjust = &((uintptr_t *)text)[addr >> 1];
             } else {
                 // Point to somewhere in rodata
                 addr_to_adjust = &((uintptr_t *)ri->rodata)[addr >> 1];
             }
         }
         op >>= 1;
         uintptr_t dest;
         size_t n = 1;
         if (op <= 5) {
             if (op & 1) {
                 // Read in number of adjustments to make
                 n = read_uint(ri->reader);
             }
             op >>= 1;
             if (op == 0) {
                 // Destination is text
                 dest = reloc_text;
             } else if (op == 1) {
                 // Destination is rodata
                 dest = (uintptr_t)ri->rodata;
             } else {
                 // Destination is bss
                 dest = (uintptr_t)ri->bss;
             }
         } else if (op == 6) {
             // Destination is qstr_table
             dest = (uintptr_t)ri->context->constants.qstr_table;
         } else if (op == 7) {
             // Destination is obj_table
             dest = (uintptr_t)ri->context->constants.obj_table;
         } else if (op == 8) {
             // Destination is mp_fun_table itself
             dest = (uintptr_t)&mp_fun_table;
         } else {
             // Destination is an entry in mp_fun_table
             dest = ((uintptr_t *)&mp_fun_table)[op - 9];
         }
         while (n--) {
             *addr_to_adjust++ += dest;
         }
     }
 }

 #endif

 static int read_byte(mp_reader_t *reader) {
     return reader->readbyte(reader->data);
 }

 static void read_bytes(mp_reader_t *reader, byte *buf, size_t len) {
     while (len-- > 0) {
         *buf++ = reader->readbyte(reader->data);
     }
 }

 static size_t read_uint(mp_reader_t *reader) {
     size_t unum = 0;
     for (;;) {
         byte b = reader->readbyte(reader->data);
         unum = (unum << 7) | (b & 0x7f);
         if ((b & 0x80) == 0) {
             break;
         }
     }
     return unum;
 }

 static qstr load_qstr(mp_reader_t *reader) {
     size_t len = read_uint(reader);
     if (len & 1) {
         // static qstr
         return len >> 1;
     }
     len >>= 1;
     char *str = m_new(char, len);
     read_bytes(reader, (byte *)str, len);
     read_byte(reader); // read and discard null terminator
     qstr qst = qstr_from_strn(str, len);
     m_del(char, str, len);
     return qst;
 }

 static mp_obj_t load_obj(mp_reader_t *reader) {
     byte obj_type = read_byte(reader);
     #if MICROPY_EMIT_MACHINE_CODE
     if (obj_type == MP_PERSISTENT_OBJ_FUN_TABLE) {
         return MP_OBJ_FROM_PTR(&mp_fun_table);
     } else
     #endif
     if (obj_type == MP_PERSISTENT_OBJ_NONE) {
         return mp_const_none;
     } else if (obj_type == MP_PERSISTENT_OBJ_FALSE) {
         return mp_const_false;
     } else if (obj_type == MP_PERSISTENT_OBJ_TRUE) {
         return mp_const_true;
     } else if (obj_type == MP_PERSISTENT_OBJ_ELLIPSIS) {
         return MP_OBJ_FROM_PTR(&mp_const_ellipsis_obj);
     } else {
         size_t len = read_uint(reader);
         if (len == 0 && obj_type == MP_PERSISTENT_OBJ_BYTES) {
             read_byte(reader); // skip null terminator
             return mp_const_empty_bytes;
         } else if (obj_type == MP_PERSISTENT_OBJ_TUPLE) {
             mp_obj_tuple_t *tuple = MP_OBJ_TO_PTR(mp_obj_new_tuple(len, NULL));
             for (size_t i = 0; i < len; ++i) {
                 tuple->items[i] = load_obj(reader);
             }
             return MP_OBJ_FROM_PTR(tuple);
         }
         vstr_t vstr;
         vstr_init_len(&vstr, len);
         read_bytes(reader, (byte *)vstr.buf, len);
         if (obj_type == MP_PERSISTENT_OBJ_STR || obj_type == MP_PERSISTENT_OBJ_BYTES) {
             read_byte(reader); // skip null terminator
             if (obj_type == MP_PERSISTENT_OBJ_STR) {
                 return mp_obj_new_str_from_utf8_vstr(&vstr);
             } else {
                 return mp_obj_new_bytes_from_vstr(&vstr);
             }
         } else if (obj_type == MP_PERSISTENT_OBJ_INT) {
             return mp_parse_num_integer(vstr.buf, vstr.len, 10, NULL);
         } else {
             assert(obj_type == MP_PERSISTENT_OBJ_FLOAT || obj_type == MP_PERSISTENT_OBJ_COMPLEX);
             return mp_parse_num_float(vstr.buf, vstr.len, obj_type == MP_PERSISTENT_OBJ_COMPLEX, NULL);
         }
     }
 }

 static mp_raw_code_t *load_raw_code(mp_reader_t *reader, mp_module_context_t *context) {
     // Load function kind and data length
     size_t kind_len = read_uint(reader);
     int kind = (kind_len & 3) + MP_CODE_BYTECODE;
     bool has_children = !!(kind_len & 4);
     size_t fun_data_len = kind_len >> 3;

     #if !MICROPY_EMIT_MACHINE_CODE
     if (kind != MP_CODE_BYTECODE) {
         mp_raise_ValueError(MP_ERROR_TEXT("incompatible .mpy file"));
     }
     #endif

     uint8_t *fun_data = NULL;
     #if MICROPY_EMIT_MACHINE_CODE
     size_t prelude_offset = 0;
     mp_uint_t native_scope_flags = 0;
     mp_uint_t native_n_pos_args = 0;
     mp_uint_t native_type_sig = 0;
     #endif

     if (kind == MP_CODE_BYTECODE) {
         // Allocate memory for the bytecode
         fun_data = m_new(uint8_t, fun_data_len);
         // Load bytecode
         read_bytes(reader, fun_data, fun_data_len);

     #if MICROPY_EMIT_MACHINE_CODE
     } else {
         // Allocate memory for native data and load it
         size_t fun_alloc;
         MP_PLAT_ALLOC_EXEC(fun_data_len, (void **)&fun_data, &fun_alloc);
         read_bytes(reader, fun_data, fun_data_len);

         if (kind == MP_CODE_NATIVE_PY) {
             // Read prelude offset within fun_data, and extract scope flags.
             prelude_offset = read_uint(reader);
             const byte *ip = fun_data + prelude_offset;
             MP_BC_PRELUDE_SIG_DECODE(ip);
             native_scope_flags = scope_flags;
         } else {
             // Load basic scope info for viper and asm.
             native_scope_flags = read_uint(reader);
             if (kind == MP_CODE_NATIVE_ASM) {
                 native_n_pos_args = read_uint(reader);
                 native_type_sig = read_uint(reader);
             }
         }
     #endif
     }

     size_t n_children = 0;
     mp_raw_code_t **children = NULL;

     #if MICROPY_EMIT_MACHINE_CODE
     // Load optional BSS/rodata for viper.
     uint8_t *rodata = NULL;
     uint8_t *bss = NULL;
     if (kind == MP_CODE_NATIVE_VIPER) {
         size_t rodata_size = 0;
         if (native_scope_flags & MP_SCOPE_FLAG_VIPERRODATA) {
             rodata_size = read_uint(reader);
         }

         size_t bss_size = 0;
         if (native_scope_flags & MP_SCOPE_FLAG_VIPERBSS) {
             bss_size = read_uint(reader);
         }

         if (rodata_size + bss_size != 0) {
             bss_size = (uintptr_t)MP_ALIGN(bss_size, sizeof(uintptr_t));
             uint8_t *data = m_new0(uint8_t, bss_size + rodata_size);
             bss = data;
             rodata = bss + bss_size;
             if (native_scope_flags & MP_SCOPE_FLAG_VIPERRODATA) {
                 read_bytes(reader, rodata, rodata_size);
             }

             #if MICROPY_PERSISTENT_CODE_TRACK_BSS_RODATA
             // Track the BSS/rodata memory so it's not reclaimed by the GC.
             track_root_pointer(data);
             #endif
         }
     }
     #endif

     // Load children if any.
     if (has_children) {
         n_children = read_uint(reader);
         children = m_new(mp_raw_code_t *, n_children + (kind == MP_CODE_NATIVE_PY));
         for (size_t i = 0; i < n_children; ++i) {
             children[i] = load_raw_code(reader, context);
         }
     }

     // Create raw_code and return it
     mp_raw_code_t *rc = mp_emit_glue_new_raw_code();
     if (kind == MP_CODE_BYTECODE) {
         const byte *ip = fun_data;
         MP_BC_PRELUDE_SIG_DECODE(ip);
         // Assign bytecode to raw code object
         mp_emit_glue_assign_bytecode(rc, fun_data,
             children,
             #if MICROPY_PERSISTENT_CODE_SAVE
             fun_data_len,
             n_children,
             #endif
             scope_flags);

     #if MICROPY_EMIT_MACHINE_CODE
     } else {
         const uint8_t *prelude_ptr;
         #if MICROPY_EMIT_NATIVE_PRELUDE_SEPARATE_FROM_MACHINE_CODE
         if (kind == MP_CODE_NATIVE_PY) {
             // Executable code cannot be accessed byte-wise on this architecture, so copy
             // the prelude to a separate memory region that is byte-wise readable.
             void *buf = fun_data + prelude_offset;
             size_t n = fun_data_len - prelude_offset;
             prelude_ptr = memcpy(m_new(uint8_t, n), buf, n);
         }
         #endif

         // Relocate and commit code to executable address space
         reloc_info_t ri = {reader, context, rodata, bss};
         #if defined(MP_PLAT_COMMIT_EXEC)
         void *opt_ri = (native_scope_flags & MP_SCOPE_FLAG_VIPERRELOC) ? &ri : NULL;
         fun_data = MP_PLAT_COMMIT_EXEC(fun_data, fun_data_len, opt_ri);
         #else
         if (native_scope_flags & MP_SCOPE_FLAG_VIPERRELOC) {
             #if MICROPY_PERSISTENT_CODE_TRACK_FUN_DATA
             // Track the function data memory so it's not reclaimed by the GC.
             track_root_pointer(fun_data);
             #endif
             // Do the relocations.
             mp_native_relocate(&ri, fun_data, (uintptr_t)fun_data);
         }
         #endif

         if (kind == MP_CODE_NATIVE_PY) {
             #if !MICROPY_EMIT_NATIVE_PRELUDE_SEPARATE_FROM_MACHINE_CODE
             prelude_ptr = fun_data + prelude_offset;
             #endif
             if (n_children == 0) {
                 children = (void *)prelude_ptr;
             } else {
                 children[n_children] = (void *)prelude_ptr;
             }
         }

         // Assign native code to raw code object
         mp_emit_glue_assign_native(rc, kind,
             fun_data, fun_data_len,
             children,
             #if MICROPY_PERSISTENT_CODE_SAVE
             n_children,
             prelude_offset,
             #endif
             native_scope_flags, native_n_pos_args, native_type_sig
             );
     #endif
     }
     return rc;
 }

 void mp_raw_code_load(mp_reader_t *reader, mp_compiled_module_t *cm) {
     // Set exception handler to close the reader if an exception is raised.
     MP_DEFINE_NLR_JUMP_CALLBACK_FUNCTION_1(ctx, reader->close, reader->data);
     nlr_push_jump_callback(&ctx.callback, mp_call_function_1_from_nlr_jump_callback);

     byte header[4];
     read_bytes(reader, header, sizeof(header));
     byte arch = MPY_FEATURE_DECODE_ARCH(header[2]);
     if (header[0] != 'M'
         || header[1] != MPY_VERSION
         || (arch != MP_NATIVE_ARCH_NONE && MPY_FEATURE_DECODE_SUB_VERSION(header[2]) != MPY_SUB_VERSION)
         || header[3] > MP_SMALL_INT_BITS) {
         mp_raise_ValueError(MP_ERROR_TEXT("incompatible .mpy file"));
     }
     if (MPY_FEATURE_DECODE_ARCH(header[2]) != MP_NATIVE_ARCH_NONE) {
         if (!MPY_FEATURE_ARCH_TEST(arch)) {
             if (MPY_FEATURE_ARCH_TEST(MP_NATIVE_ARCH_NONE)) {
                 // On supported ports this can be resolved by enabling feature, eg
                 // mpconfigboard.h: MICROPY_EMIT_THUMB (1)
                 mp_raise_ValueError(MP_ERROR_TEXT("native code in .mpy unsupported"));
             } else {
                 mp_raise_ValueError(MP_ERROR_TEXT("incompatible .mpy arch"));
             }
         }
     }

     size_t n_qstr = read_uint(reader);
     size_t n_obj = read_uint(reader);
     mp_module_context_alloc_tables(cm->context, n_qstr, n_obj);

     // Load qstrs.
     for (size_t i = 0; i < n_qstr; ++i) {
         cm->context->constants.qstr_table[i] = load_qstr(reader);
     }

     // Load constant objects.
     for (size_t i = 0; i < n_obj; ++i) {
         cm->context->constants.obj_table[i] = load_obj(reader);
     }

     // Load top-level module.
     cm->rc = load_raw_code(reader, cm->context);

     #if MICROPY_PERSISTENT_CODE_SAVE
     cm->has_native = MPY_FEATURE_DECODE_ARCH(header[2]) != MP_NATIVE_ARCH_NONE;
     cm->n_qstr = n_qstr;
     cm->n_obj = n_obj;
     #endif

     // Deregister exception handler and close the reader.
     nlr_pop_jump_callback(true);
 }

 void mp_raw_code_load_mem(const byte *buf, size_t len, mp_compiled_module_t *context) {
     mp_reader_t reader;
     mp_reader_new_mem(&reader, buf, len, 0);
     mp_raw_code_load(&reader, context);
 }

 #if MICROPY_HAS_FILE_READER

 void mp_raw_code_load_file(qstr filename, mp_compiled_module_t *context) {
     mp_reader_t reader;
     mp_reader_new_file(&reader, filename);
     mp_raw_code_load(&reader, context);
 }

 #endif // MICROPY_HAS_FILE_READER

 #endif // MICROPY_PERSISTENT_CODE_LOAD

 #if MICROPY_PERSISTENT_CODE_SAVE

 #include "py/objstr.h"

 static void mp_print_bytes(mp_print_t *print, const byte *data, size_t len) {
     print->print_strn(print->data, (const char *)data, len);
 }

 #define BYTES_FOR_INT ((MP_BYTES_PER_OBJ_WORD * 8 + 6) / 7)
 static void mp_print_uint(mp_print_t *print, size_t n) {
     byte buf[BYTES_FOR_INT];
     byte *p = buf + sizeof(buf);
     *--p = n & 0x7f;
     n >>= 7;
     for (; n != 0; n >>= 7) {
         *--p = 0x80 | (n & 0x7f);
     }
     print->print_strn(print->data, (char *)p, buf + sizeof(buf) - p);
 }

 static void save_qstr(mp_print_t *print, qstr qst) {
     if (qst <= QSTR_LAST_STATIC) {
         // encode static qstr
         mp_print_uint(print, qst << 1 | 1);
         return;
     }
     size_t len;
     const byte *str = qstr_data(qst, &len);
     mp_print_uint(print, len << 1);
     mp_print_bytes(print, str, len + 1); // +1 to store null terminator
 }

 static void save_obj(mp_print_t *print, mp_obj_t o) {
     #if MICROPY_EMIT_MACHINE_CODE
     if (o == MP_OBJ_FROM_PTR(&mp_fun_table)) {
         byte obj_type = MP_PERSISTENT_OBJ_FUN_TABLE;
         mp_print_bytes(print, &obj_type, 1);
     } else
     #endif
     if (mp_obj_is_str_or_bytes(o)) {
         byte obj_type;
         if (mp_obj_is_str(o)) {
             obj_type = MP_PERSISTENT_OBJ_STR;
         } else {
             obj_type = MP_PERSISTENT_OBJ_BYTES;
         }
         size_t len;
         const char *str = mp_obj_str_get_data(o, &len);
         mp_print_bytes(print, &obj_type, 1);
         mp_print_uint(print, len);
         mp_print_bytes(print, (const byte *)str, len + 1); // +1 to store null terminator
     } else if (o == mp_const_none) {
         byte obj_type = MP_PERSISTENT_OBJ_NONE;
         mp_print_bytes(print, &obj_type, 1);
     } else if (o == mp_const_false) {
         byte obj_type = MP_PERSISTENT_OBJ_FALSE;
         mp_print_bytes(print, &obj_type, 1);
     } else if (o == mp_const_true) {
         byte obj_type = MP_PERSISTENT_OBJ_TRUE;
         mp_print_bytes(print, &obj_type, 1);
     } else if (MP_OBJ_TO_PTR(o) == &mp_const_ellipsis_obj) {
         byte obj_type = MP_PERSISTENT_OBJ_ELLIPSIS;
         mp_print_bytes(print, &obj_type, 1);
     } else if (mp_obj_is_type(o, &mp_type_tuple)) {
         size_t len;
         mp_obj_t *items;
         mp_obj_tuple_get(o, &len, &items);
         byte obj_type = MP_PERSISTENT_OBJ_TUPLE;
         mp_print_bytes(print, &obj_type, 1);
         mp_print_uint(print, len);
         for (size_t i = 0; i < len; ++i) {
             save_obj(print, items[i]);
         }
     } else {
         // we save numbers using a simplistic text representation
         // TODO could be improved
         byte obj_type;
         if (mp_obj_is_int(o)) {
             obj_type = MP_PERSISTENT_OBJ_INT;
         #if MICROPY_PY_BUILTINS_COMPLEX
         } else if (mp_obj_is_type(o, &mp_type_complex)) {
             obj_type = MP_PERSISTENT_OBJ_COMPLEX;
         #endif
         } else {
             assert(mp_obj_is_float(o));
             obj_type = MP_PERSISTENT_OBJ_FLOAT;
         }
         vstr_t vstr;
         mp_print_t pr;
         vstr_init_print(&vstr, 10, &pr);
         mp_obj_print_helper(&pr, o, PRINT_REPR);
         mp_print_bytes(print, &obj_type, 1);
         mp_print_uint(print, vstr.len);
         mp_print_bytes(print, (const byte *)vstr.buf, vstr.len);
         vstr_clear(&vstr);
     }
 }

 static void save_raw_code(mp_print_t *print, const mp_raw_code_t *rc) {
     // Save function kind and data length
     mp_print_uint(print, (rc->fun_data_len << 3) | ((rc->n_children != 0) << 2) | (rc->kind - MP_CODE_BYTECODE));

     // Save function code.
     mp_print_bytes(print, rc->fun_data, rc->fun_data_len);

     #if MICROPY_EMIT_MACHINE_CODE
     if (rc->kind == MP_CODE_NATIVE_PY) {
         // Save prelude size
         mp_print_uint(print, rc->prelude_offset);
     } else if (rc->kind == MP_CODE_NATIVE_VIPER || rc->kind == MP_CODE_NATIVE_ASM) {
         // Save basic scope info for viper and asm
         // Viper/asm functions don't support generator, variable args, or default keyword args
         // so (scope_flags & MP_SCOPE_FLAG_ALL_SIG) for these functions is always 0.
         mp_print_uint(print, 0);
         #if MICROPY_EMIT_INLINE_ASM
         if (rc->kind == MP_CODE_NATIVE_ASM) {
             mp_print_uint(print, rc->asm_n_pos_args);
             mp_print_uint(print, rc->asm_type_sig);
         }
         #endif
     }
     #endif

     if (rc->n_children) {
         mp_print_uint(print, rc->n_children);
         for (size_t i = 0; i < rc->n_children; ++i) {
             save_raw_code(print, rc->children[i]);
         }
     }
 }

 void mp_raw_code_save(mp_compiled_module_t *cm, mp_print_t *print) {
     // header contains:
     //  byte  'M'
     //  byte  version
     //  byte  native arch (and sub-version if native)
     //  byte  number of bits in a small int
     byte header[4] = {
         'M',
         MPY_VERSION,
         cm->has_native ? MPY_FEATURE_ENCODE_SUB_VERSION(MPY_SUB_VERSION) | MPY_FEATURE_ENCODE_ARCH(MPY_FEATURE_ARCH_DYNAMIC) : 0,
         #if MICROPY_DYNAMIC_COMPILER
         mp_dynamic_compiler.small_int_bits,
         #else
         MP_SMALL_INT_BITS,
         #endif
     };
     mp_print_bytes(print, header, sizeof(header));

     // Number of entries in constant table.
     mp_print_uint(print, cm->n_qstr);
     mp_print_uint(print, cm->n_obj);

     // Save qstrs.
     for (size_t i = 0; i < cm->n_qstr; ++i) {
         save_qstr(print, cm->context->constants.qstr_table[i]);
     }

     // Save constant objects.
     for (size_t i = 0; i < cm->n_obj; ++i) {
         save_obj(print, (mp_obj_t)cm->context->constants.obj_table[i]);
     }

     // Save outer raw code, which will save all its child raw codes.
     save_raw_code(print, cm->rc);
 }

 #if MICROPY_PERSISTENT_CODE_SAVE_FILE

 #include <unistd.h>
 #include <sys/stat.h>
 #include <fcntl.h>

 static void fd_print_strn(void *env, const char *str, size_t len) {
     int fd = (intptr_t)env;
     MP_THREAD_GIL_EXIT();
     ssize_t ret = write(fd, str, len);
     MP_THREAD_GIL_ENTER();
     (void)ret;
 }

 void mp_raw_code_save_file(mp_compiled_module_t *cm, qstr filename) {
     MP_THREAD_GIL_EXIT();
     int fd = open(qstr_str(filename), O_WRONLY | O_CREAT | O_TRUNC, 0644);
     MP_THREAD_GIL_ENTER();
     if (fd < 0) {
         mp_raise_OSError_with_filename(errno, qstr_str(filename));
     }
     mp_print_t fd_print = {(void *)(intptr_t)fd, fd_print_strn};
     mp_raw_code_save(cm, &fd_print);
     MP_THREAD_GIL_EXIT();
     close(fd);
     MP_THREAD_GIL_ENTER();
 }

 #endif // MICROPY_PERSISTENT_CODE_SAVE_FILE

 #endif // MICROPY_PERSISTENT_CODE_SAVE
	/*
	* This file is part of the MicroPython project, http://micropython.org/
	*
	* The MIT License (MIT)
	*
	* Copyright (c) 2013-2020 Damien P. George
	*
	* 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 <stdint.h>
	#include <stdio.h>
	#include <string.h>
	#include <assert.h>

	#include "py/reader.h"
	#include "py/nativeglue.h"
	#include "py/persistentcode.h"
	#include "py/bc0.h"
	#include "py/objstr.h"
	#include "py/mpthread.h"

	#if MICROPY_PERSISTENT_CODE_LOAD \|\| MICROPY_PERSISTENT_CODE_SAVE

	#include "py/smallint.h"

	// makeqstrdata.py has a fixed list of qstrs at the start that we can assume
	// are available with know indices on all MicroPython implementations, and
	// avoid needing to duplicate the string data in the .mpy file. This is the
	// last one in that list (anything with a qstr less than or equal to this is
	// assumed to be in the list).
	#define QSTR_LAST_STATIC MP_QSTR_zip

	#if MICROPY_DYNAMIC_COMPILER
	#define MPY_FEATURE_ARCH_DYNAMIC mp_dynamic_compiler.native_arch
	#else
	#define MPY_FEATURE_ARCH_DYNAMIC MPY_FEATURE_ARCH
	#endif

	typedef struct _bytecode_prelude_t {
	uint n_state;
	uint n_exc_stack;
	uint scope_flags;
	uint n_pos_args;
	uint n_kwonly_args;
	uint n_def_pos_args;
	uint code_info_size;
	} bytecode_prelude_t;

	#endif // MICROPY_PERSISTENT_CODE_LOAD \|\| MICROPY_PERSISTENT_CODE_SAVE

	#if MICROPY_PERSISTENT_CODE_LOAD

	#include "py/parsenum.h"

	static int read_byte(mp_reader_t *reader);
	static size_t read_uint(mp_reader_t *reader);

	#if MICROPY_PERSISTENT_CODE_TRACK_FUN_DATA \|\| MICROPY_PERSISTENT_CODE_TRACK_BSS_RODATA

	// An mp_obj_list_t that tracks native text/BSS/rodata to prevent the GC from reclaiming them.
	MP_REGISTER_ROOT_POINTER(mp_obj_t persistent_code_root_pointers);

	static void track_root_pointer(void *ptr) {
	if (MP_STATE_PORT(persistent_code_root_pointers) == MP_OBJ_NULL) {
	MP_STATE_PORT(persistent_code_root_pointers) = mp_obj_new_list(0, NULL);
	}
	mp_obj_list_append(MP_STATE_PORT(persistent_code_root_pointers), MP_OBJ_FROM_PTR(ptr));
	}

	#endif

	#if MICROPY_EMIT_MACHINE_CODE

	typedef struct _reloc_info_t {
	mp_reader_t *reader;
	mp_module_context_t *context;
	uint8_t *rodata;
	uint8_t *bss;
	} reloc_info_t;

	void mp_native_relocate(void ri_in, uint8_t text, uintptr_t reloc_text) {
	// Relocate native code
	reloc_info_t *ri = ri_in;
	uint8_t op;
	uintptr_t *addr_to_adjust = NULL;
	while ((op = read_byte(ri->reader)) != 0xff) {
	if (op & 1) {
	// Point to new location to make adjustments
	size_t addr = read_uint(ri->reader);
	if ((addr & 1) == 0) {
	// Point to somewhere in text
	addr_to_adjust = &((uintptr_t *)text)[addr >> 1];
	} else {
	// Point to somewhere in rodata
	addr_to_adjust = &((uintptr_t *)ri->rodata)[addr >> 1];
	}
	}
	op >>= 1;
	uintptr_t dest;
	size_t n = 1;
	if (op <= 5) {
	if (op & 1) {
	// Read in number of adjustments to make
	n = read_uint(ri->reader);
	}
	op >>= 1;
	if (op == 0) {
	// Destination is text
	dest = reloc_text;
	} else if (op == 1) {
	// Destination is rodata
	dest = (uintptr_t)ri->rodata;
	} else {
	// Destination is bss
	dest = (uintptr_t)ri->bss;
	}
	} else if (op == 6) {
	// Destination is qstr_table
	dest = (uintptr_t)ri->context->constants.qstr_table;
	} else if (op == 7) {
	// Destination is obj_table
	dest = (uintptr_t)ri->context->constants.obj_table;
	} else if (op == 8) {
	// Destination is mp_fun_table itself
	dest = (uintptr_t)&mp_fun_table;
	} else {
	// Destination is an entry in mp_fun_table
	dest = ((uintptr_t *)&mp_fun_table)[op - 9];
	}
	while (n--) {
	*addr_to_adjust++ += dest;
	}
	}
	}

	#endif

	static int read_byte(mp_reader_t *reader) {
	return reader->readbyte(reader->data);
	}

	static void read_bytes(mp_reader_t reader, byte buf, size_t len) {
	while (len-- > 0) {
	*buf++ = reader->readbyte(reader->data);
	}
	}

	static size_t read_uint(mp_reader_t *reader) {
	size_t unum = 0;
	for (;;) {
	byte b = reader->readbyte(reader->data);
	unum = (unum << 7) \| (b & 0x7f);
	if ((b & 0x80) == 0) {
	break;
	}
	}
	return unum;
	}

	static qstr load_qstr(mp_reader_t *reader) {
	size_t len = read_uint(reader);
	if (len & 1) {
	// static qstr
	return len >> 1;
	}
	len >>= 1;
	char *str = m_new(char, len);
	read_bytes(reader, (byte *)str, len);
	read_byte(reader); // read and discard null terminator
	qstr qst = qstr_from_strn(str, len);
	m_del(char, str, len);
	return qst;
	}

	static mp_obj_t load_obj(mp_reader_t *reader) {
	byte obj_type = read_byte(reader);
	#if MICROPY_EMIT_MACHINE_CODE
	if (obj_type == MP_PERSISTENT_OBJ_FUN_TABLE) {
	return MP_OBJ_FROM_PTR(&mp_fun_table);
	} else
	#endif
	if (obj_type == MP_PERSISTENT_OBJ_NONE) {
	return mp_const_none;
	} else if (obj_type == MP_PERSISTENT_OBJ_FALSE) {
	return mp_const_false;
	} else if (obj_type == MP_PERSISTENT_OBJ_TRUE) {
	return mp_const_true;
	} else if (obj_type == MP_PERSISTENT_OBJ_ELLIPSIS) {
	return MP_OBJ_FROM_PTR(&mp_const_ellipsis_obj);
	} else {
	size_t len = read_uint(reader);
	if (len == 0 && obj_type == MP_PERSISTENT_OBJ_BYTES) {
	read_byte(reader); // skip null terminator
	return mp_const_empty_bytes;
	} else if (obj_type == MP_PERSISTENT_OBJ_TUPLE) {
	mp_obj_tuple_t *tuple = MP_OBJ_TO_PTR(mp_obj_new_tuple(len, NULL));
	for (size_t i = 0; i < len; ++i) {
	tuple->items[i] = load_obj(reader);
	}
	return MP_OBJ_FROM_PTR(tuple);
	}
	vstr_t vstr;
	vstr_init_len(&vstr, len);
	read_bytes(reader, (byte *)vstr.buf, len);
	if (obj_type == MP_PERSISTENT_OBJ_STR \|\| obj_type == MP_PERSISTENT_OBJ_BYTES) {
	read_byte(reader); // skip null terminator
	if (obj_type == MP_PERSISTENT_OBJ_STR) {
	return mp_obj_new_str_from_utf8_vstr(&vstr);
	} else {
	return mp_obj_new_bytes_from_vstr(&vstr);
	}
	} else if (obj_type == MP_PERSISTENT_OBJ_INT) {
	return mp_parse_num_integer(vstr.buf, vstr.len, 10, NULL);
	} else {
	assert(obj_type == MP_PERSISTENT_OBJ_FLOAT \|\| obj_type == MP_PERSISTENT_OBJ_COMPLEX);
	return mp_parse_num_float(vstr.buf, vstr.len, obj_type == MP_PERSISTENT_OBJ_COMPLEX, NULL);
	}
	}
	}

	static mp_raw_code_t load_raw_code(mp_reader_t reader, mp_module_context_t *context) {
	// Load function kind and data length
	size_t kind_len = read_uint(reader);
	int kind = (kind_len & 3) + MP_CODE_BYTECODE;
	bool has_children = !!(kind_len & 4);
	size_t fun_data_len = kind_len >> 3;

	#if !MICROPY_EMIT_MACHINE_CODE
	if (kind != MP_CODE_BYTECODE) {
	mp_raise_ValueError(MP_ERROR_TEXT("incompatible .mpy file"));
	}
	#endif

	uint8_t *fun_data = NULL;
	#if MICROPY_EMIT_MACHINE_CODE
	size_t prelude_offset = 0;
	mp_uint_t native_scope_flags = 0;
	mp_uint_t native_n_pos_args = 0;
	mp_uint_t native_type_sig = 0;
	#endif

	if (kind == MP_CODE_BYTECODE) {
	// Allocate memory for the bytecode
	fun_data = m_new(uint8_t, fun_data_len);
	// Load bytecode
	read_bytes(reader, fun_data, fun_data_len);

	#if MICROPY_EMIT_MACHINE_CODE
	} else {
	// Allocate memory for native data and load it
	size_t fun_alloc;
	MP_PLAT_ALLOC_EXEC(fun_data_len, (void **)&fun_data, &fun_alloc);
	read_bytes(reader, fun_data, fun_data_len);

	if (kind == MP_CODE_NATIVE_PY) {
	// Read prelude offset within fun_data, and extract scope flags.
	prelude_offset = read_uint(reader);
	const byte *ip = fun_data + prelude_offset;
	MP_BC_PRELUDE_SIG_DECODE(ip);
	native_scope_flags = scope_flags;
	} else {
	// Load basic scope info for viper and asm.
	native_scope_flags = read_uint(reader);
	if (kind == MP_CODE_NATIVE_ASM) {
	native_n_pos_args = read_uint(reader);
	native_type_sig = read_uint(reader);
	}
	}
	#endif
	}

	size_t n_children = 0;
	mp_raw_code_t **children = NULL;

	#if MICROPY_EMIT_MACHINE_CODE
	// Load optional BSS/rodata for viper.
	uint8_t *rodata = NULL;
	uint8_t *bss = NULL;
	if (kind == MP_CODE_NATIVE_VIPER) {
	size_t rodata_size = 0;
	if (native_scope_flags & MP_SCOPE_FLAG_VIPERRODATA) {
	rodata_size = read_uint(reader);
	}

	size_t bss_size = 0;
	if (native_scope_flags & MP_SCOPE_FLAG_VIPERBSS) {
	bss_size = read_uint(reader);
	}

	if (rodata_size + bss_size != 0) {
	bss_size = (uintptr_t)MP_ALIGN(bss_size, sizeof(uintptr_t));
	uint8_t *data = m_new0(uint8_t, bss_size + rodata_size);
	bss = data;
	rodata = bss + bss_size;
	if (native_scope_flags & MP_SCOPE_FLAG_VIPERRODATA) {
	read_bytes(reader, rodata, rodata_size);
	}

	#if MICROPY_PERSISTENT_CODE_TRACK_BSS_RODATA
	// Track the BSS/rodata memory so it's not reclaimed by the GC.
	track_root_pointer(data);
	#endif
	}
	}
	#endif

	// Load children if any.
	if (has_children) {
	n_children = read_uint(reader);
	children = m_new(mp_raw_code_t *, n_children + (kind == MP_CODE_NATIVE_PY));
	for (size_t i = 0; i < n_children; ++i) {
	children[i] = load_raw_code(reader, context);
	}
	}

	// Create raw_code and return it
	mp_raw_code_t *rc = mp_emit_glue_new_raw_code();
	if (kind == MP_CODE_BYTECODE) {
	const byte *ip = fun_data;
	MP_BC_PRELUDE_SIG_DECODE(ip);
	// Assign bytecode to raw code object
	mp_emit_glue_assign_bytecode(rc, fun_data,
	children,
	#if MICROPY_PERSISTENT_CODE_SAVE
	fun_data_len,
	n_children,
	#endif
	scope_flags);

	#if MICROPY_EMIT_MACHINE_CODE
	} else {
	const uint8_t *prelude_ptr;
	#if MICROPY_EMIT_NATIVE_PRELUDE_SEPARATE_FROM_MACHINE_CODE
	if (kind == MP_CODE_NATIVE_PY) {
	// Executable code cannot be accessed byte-wise on this architecture, so copy
	// the prelude to a separate memory region that is byte-wise readable.
	void *buf = fun_data + prelude_offset;
	size_t n = fun_data_len - prelude_offset;
	prelude_ptr = memcpy(m_new(uint8_t, n), buf, n);
	}
	#endif

	// Relocate and commit code to executable address space
	reloc_info_t ri = {reader, context, rodata, bss};
	#if defined(MP_PLAT_COMMIT_EXEC)
	void *opt_ri = (native_scope_flags & MP_SCOPE_FLAG_VIPERRELOC) ? &ri : NULL;
	fun_data = MP_PLAT_COMMIT_EXEC(fun_data, fun_data_len, opt_ri);
	#else
	if (native_scope_flags & MP_SCOPE_FLAG_VIPERRELOC) {
	#if MICROPY_PERSISTENT_CODE_TRACK_FUN_DATA
	// Track the function data memory so it's not reclaimed by the GC.
	track_root_pointer(fun_data);
	#endif
	// Do the relocations.
	mp_native_relocate(&ri, fun_data, (uintptr_t)fun_data);
	}
	#endif

	if (kind == MP_CODE_NATIVE_PY) {
	#if !MICROPY_EMIT_NATIVE_PRELUDE_SEPARATE_FROM_MACHINE_CODE
	prelude_ptr = fun_data + prelude_offset;
	#endif
	if (n_children == 0) {
	children = (void *)prelude_ptr;
	} else {
	children[n_children] = (void *)prelude_ptr;
	}
	}

	// Assign native code to raw code object
	mp_emit_glue_assign_native(rc, kind,
	fun_data, fun_data_len,
	children,
	#if MICROPY_PERSISTENT_CODE_SAVE
	n_children,
	prelude_offset,
	#endif
	native_scope_flags, native_n_pos_args, native_type_sig
	);
	#endif
	}
	return rc;
	}

	void mp_raw_code_load(mp_reader_t reader, mp_compiled_module_t cm) {
	// Set exception handler to close the reader if an exception is raised.
	MP_DEFINE_NLR_JUMP_CALLBACK_FUNCTION_1(ctx, reader->close, reader->data);
	nlr_push_jump_callback(&ctx.callback, mp_call_function_1_from_nlr_jump_callback);

	byte header[4];
	read_bytes(reader, header, sizeof(header));
	byte arch = MPY_FEATURE_DECODE_ARCH(header[2]);
	if (header[0] != 'M'
	\|\| header[1] != MPY_VERSION
	\|\| (arch != MP_NATIVE_ARCH_NONE && MPY_FEATURE_DECODE_SUB_VERSION(header[2]) != MPY_SUB_VERSION)
	\|\| header[3] > MP_SMALL_INT_BITS) {
	mp_raise_ValueError(MP_ERROR_TEXT("incompatible .mpy file"));
	}
	if (MPY_FEATURE_DECODE_ARCH(header[2]) != MP_NATIVE_ARCH_NONE) {
	if (!MPY_FEATURE_ARCH_TEST(arch)) {
	if (MPY_FEATURE_ARCH_TEST(MP_NATIVE_ARCH_NONE)) {
	// On supported ports this can be resolved by enabling feature, eg
	// mpconfigboard.h: MICROPY_EMIT_THUMB (1)
	mp_raise_ValueError(MP_ERROR_TEXT("native code in .mpy unsupported"));
	} else {
	mp_raise_ValueError(MP_ERROR_TEXT("incompatible .mpy arch"));
	}
	}
	}

	size_t n_qstr = read_uint(reader);
	size_t n_obj = read_uint(reader);
	mp_module_context_alloc_tables(cm->context, n_qstr, n_obj);

	// Load qstrs.
	for (size_t i = 0; i < n_qstr; ++i) {
	cm->context->constants.qstr_table[i] = load_qstr(reader);
	}

	// Load constant objects.
	for (size_t i = 0; i < n_obj; ++i) {
	cm->context->constants.obj_table[i] = load_obj(reader);
	}

	// Load top-level module.
	cm->rc = load_raw_code(reader, cm->context);

	#if MICROPY_PERSISTENT_CODE_SAVE
	cm->has_native = MPY_FEATURE_DECODE_ARCH(header[2]) != MP_NATIVE_ARCH_NONE;
	cm->n_qstr = n_qstr;
	cm->n_obj = n_obj;
	#endif

	// Deregister exception handler and close the reader.
	nlr_pop_jump_callback(true);
	}

	void mp_raw_code_load_mem(const byte buf, size_t len, mp_compiled_module_t context) {
	mp_reader_t reader;
	mp_reader_new_mem(&reader, buf, len, 0);
	mp_raw_code_load(&reader, context);
	}

	#if MICROPY_HAS_FILE_READER

	void mp_raw_code_load_file(qstr filename, mp_compiled_module_t *context) {
	mp_reader_t reader;
	mp_reader_new_file(&reader, filename);
	mp_raw_code_load(&reader, context);
	}

	#endif // MICROPY_HAS_FILE_READER

	#endif // MICROPY_PERSISTENT_CODE_LOAD

	#if MICROPY_PERSISTENT_CODE_SAVE

	#include "py/objstr.h"

	static void mp_print_bytes(mp_print_t print, const byte data, size_t len) {
	print->print_strn(print->data, (const char *)data, len);
	}

	#define BYTES_FOR_INT ((MP_BYTES_PER_OBJ_WORD * 8 + 6) / 7)
	static void mp_print_uint(mp_print_t *print, size_t n) {
	byte buf[BYTES_FOR_INT];
	byte *p = buf + sizeof(buf);
	*--p = n & 0x7f;
	n >>= 7;
	for (; n != 0; n >>= 7) {
	*--p = 0x80 \| (n & 0x7f);
	}
	print->print_strn(print->data, (char *)p, buf + sizeof(buf) - p);
	}

	static void save_qstr(mp_print_t *print, qstr qst) {
	if (qst <= QSTR_LAST_STATIC) {
	// encode static qstr
	mp_print_uint(print, qst << 1 \| 1);
	return;
	}
	size_t len;
	const byte *str = qstr_data(qst, &len);
	mp_print_uint(print, len << 1);
	mp_print_bytes(print, str, len + 1); // +1 to store null terminator
	}

	static void save_obj(mp_print_t *print, mp_obj_t o) {
	#if MICROPY_EMIT_MACHINE_CODE
	if (o == MP_OBJ_FROM_PTR(&mp_fun_table)) {
	byte obj_type = MP_PERSISTENT_OBJ_FUN_TABLE;
	mp_print_bytes(print, &obj_type, 1);
	} else
	#endif
	if (mp_obj_is_str_or_bytes(o)) {
	byte obj_type;
	if (mp_obj_is_str(o)) {
	obj_type = MP_PERSISTENT_OBJ_STR;
	} else {
	obj_type = MP_PERSISTENT_OBJ_BYTES;
	}
	size_t len;
	const char *str = mp_obj_str_get_data(o, &len);
	mp_print_bytes(print, &obj_type, 1);
	mp_print_uint(print, len);
	mp_print_bytes(print, (const byte *)str, len + 1); // +1 to store null terminator
	} else if (o == mp_const_none) {
	byte obj_type = MP_PERSISTENT_OBJ_NONE;
	mp_print_bytes(print, &obj_type, 1);
	} else if (o == mp_const_false) {
	byte obj_type = MP_PERSISTENT_OBJ_FALSE;
	mp_print_bytes(print, &obj_type, 1);
	} else if (o == mp_const_true) {
	byte obj_type = MP_PERSISTENT_OBJ_TRUE;
	mp_print_bytes(print, &obj_type, 1);
	} else if (MP_OBJ_TO_PTR(o) == &mp_const_ellipsis_obj) {
	byte obj_type = MP_PERSISTENT_OBJ_ELLIPSIS;
	mp_print_bytes(print, &obj_type, 1);
	} else if (mp_obj_is_type(o, &mp_type_tuple)) {
	size_t len;
	mp_obj_t *items;
	mp_obj_tuple_get(o, &len, &items);
	byte obj_type = MP_PERSISTENT_OBJ_TUPLE;
	mp_print_bytes(print, &obj_type, 1);
	mp_print_uint(print, len);
	for (size_t i = 0; i < len; ++i) {
	save_obj(print, items[i]);
	}
	} else {
	// we save numbers using a simplistic text representation
	// TODO could be improved
	byte obj_type;
	if (mp_obj_is_int(o)) {
	obj_type = MP_PERSISTENT_OBJ_INT;
	#if MICROPY_PY_BUILTINS_COMPLEX
	} else if (mp_obj_is_type(o, &mp_type_complex)) {
	obj_type = MP_PERSISTENT_OBJ_COMPLEX;
	#endif
	} else {
	assert(mp_obj_is_float(o));
	obj_type = MP_PERSISTENT_OBJ_FLOAT;
	}
	vstr_t vstr;
	mp_print_t pr;
	vstr_init_print(&vstr, 10, &pr);
	mp_obj_print_helper(&pr, o, PRINT_REPR);
	mp_print_bytes(print, &obj_type, 1);
	mp_print_uint(print, vstr.len);
	mp_print_bytes(print, (const byte *)vstr.buf, vstr.len);
	vstr_clear(&vstr);
	}
	}

	static void save_raw_code(mp_print_t print, const mp_raw_code_t rc) {
	// Save function kind and data length
	mp_print_uint(print, (rc->fun_data_len << 3) \| ((rc->n_children != 0) << 2) \| (rc->kind - MP_CODE_BYTECODE));

	// Save function code.
	mp_print_bytes(print, rc->fun_data, rc->fun_data_len);

	#if MICROPY_EMIT_MACHINE_CODE
	if (rc->kind == MP_CODE_NATIVE_PY) {
	// Save prelude size
	mp_print_uint(print, rc->prelude_offset);
	} else if (rc->kind == MP_CODE_NATIVE_VIPER \|\| rc->kind == MP_CODE_NATIVE_ASM) {
	// Save basic scope info for viper and asm
	// Viper/asm functions don't support generator, variable args, or default keyword args
	// so (scope_flags & MP_SCOPE_FLAG_ALL_SIG) for these functions is always 0.
	mp_print_uint(print, 0);
	#if MICROPY_EMIT_INLINE_ASM
	if (rc->kind == MP_CODE_NATIVE_ASM) {
	mp_print_uint(print, rc->asm_n_pos_args);
	mp_print_uint(print, rc->asm_type_sig);
	}
	#endif
	}
	#endif

	if (rc->n_children) {
	mp_print_uint(print, rc->n_children);
	for (size_t i = 0; i < rc->n_children; ++i) {
	save_raw_code(print, rc->children[i]);
	}
	}
	}

	void mp_raw_code_save(mp_compiled_module_t cm, mp_print_t print) {
	// header contains:
	// byte 'M'
	// byte version
	// byte native arch (and sub-version if native)
	// byte number of bits in a small int
	byte header[4] = {
	'M',
	MPY_VERSION,
	cm->has_native ? MPY_FEATURE_ENCODE_SUB_VERSION(MPY_SUB_VERSION) \| MPY_FEATURE_ENCODE_ARCH(MPY_FEATURE_ARCH_DYNAMIC) : 0,
	#if MICROPY_DYNAMIC_COMPILER
	mp_dynamic_compiler.small_int_bits,
	#else
	MP_SMALL_INT_BITS,
	#endif
	};
	mp_print_bytes(print, header, sizeof(header));

	// Number of entries in constant table.
	mp_print_uint(print, cm->n_qstr);
	mp_print_uint(print, cm->n_obj);

	// Save qstrs.
	for (size_t i = 0; i < cm->n_qstr; ++i) {
	save_qstr(print, cm->context->constants.qstr_table[i]);
	}

	// Save constant objects.
	for (size_t i = 0; i < cm->n_obj; ++i) {
	save_obj(print, (mp_obj_t)cm->context->constants.obj_table[i]);
	}

	// Save outer raw code, which will save all its child raw codes.
	save_raw_code(print, cm->rc);
	}

	#if MICROPY_PERSISTENT_CODE_SAVE_FILE

	#include <unistd.h>
	#include <sys/stat.h>
	#include <fcntl.h>

	static void fd_print_strn(void env, const char str, size_t len) {
	int fd = (intptr_t)env;
	MP_THREAD_GIL_EXIT();
	ssize_t ret = write(fd, str, len);
	MP_THREAD_GIL_ENTER();
	(void)ret;
	}

	void mp_raw_code_save_file(mp_compiled_module_t *cm, qstr filename) {
	MP_THREAD_GIL_EXIT();
	int fd = open(qstr_str(filename), O_WRONLY \| O_CREAT \| O_TRUNC, 0644);
	MP_THREAD_GIL_ENTER();
	if (fd < 0) {
	mp_raise_OSError_with_filename(errno, qstr_str(filename));
	}
	mp_print_t fd_print = {(void *)(intptr_t)fd, fd_print_strn};
	mp_raw_code_save(cm, &fd_print);
	MP_THREAD_GIL_EXIT();
	close(fd);
	MP_THREAD_GIL_ENTER();
	}

	#endif // MICROPY_PERSISTENT_CODE_SAVE_FILE

	#endif // MICROPY_PERSISTENT_CODE_SAVE