/* Definitions for bytecode */

#ifndef Py_LIMITED_API
#ifndef Py_CODE_H
#define Py_CODE_H
#ifdef __cplusplus
extern "C" {
#endif

typedef uint16_t _Py_CODEUNIT;

#ifdef WORDS_BIGENDIAN
# define _Py_OPCODE(word) ((word) >> 8)
# define _Py_OPARG(word) ((word) & 255)
#else
# define _Py_OPCODE(word) ((word) & 255)
# define _Py_OPARG(word) ((word) >> 8)
#endif

typedef struct _PyOpcache _PyOpcache;

/* Bytecode object */
typedef struct {
 PyObject_HEAD
 int co_argcount; /* #arguments, except *args */
 int co_posonlyargcount; /* #positional only arguments */
 int co_kwonlyargcount; /* #keyword only arguments */
 int co_nlocals; /* #local variables */
 int co_stacksize; /* #entries needed for evaluation stack */
 int co_flags; /* CO_..., see below */
 int co_firstlineno; /* first source line number */
 PyObject *co_code; /* instruction opcodes */
 PyObject *co_consts; /* list (constants used) */
 PyObject *co_names; /* list of strings (names used) */
 PyObject *co_varnames; /* tuple of strings (local variable names) */
 PyObject *co_freevars; /* tuple of strings (free variable names) */
 PyObject *co_cellvars; /* tuple of strings (cell variable names) */
 /* The rest aren't used in either hash or comparisons, except for co_name,
 used in both. This is done to preserve the name and line number
 for tracebacks and debuggers; otherwise, constant de-duplication
 would collapse identical functions/lambdas defined on different lines.
 */
 Py_ssize_t *co_cell2arg; /* Maps cell vars which are arguments. */
 PyObject *co_filename; /* unicode (where it was loaded from) */
 PyObject *co_name; /* unicode (name, for reference) */
 PyObject *co_lnotab; /* string (encoding addr<->lineno mapping) See
 Objects/lnotab_notes.txt for details. */
 void *co_zombieframe; /* for optimization only (see frameobject.c) */
 PyObject *co_weakreflist; /* to support weakrefs to code objects */
 /* Scratch space for extra data relating to the code object.
 Type is a void* to keep the format private in codeobject.c to force
 people to go through the proper APIs. */
 void *co_extra;

 /* Per opcodes just-in-time cache
 *
 * To reduce cache size, we use indirect mapping from opcode index to
 * cache object:
 * cache = co_opcache[co_opcache_map[next_instr - first_instr] - 1]
 */

 // co_opcache_map is indexed by (next_instr - first_instr).
 // * 0 means there is no cache for this opcode.
 // * n > 0 means there is cache in co_opcache[n-1].
 unsigned char *co_opcache_map;
 _PyOpcache *co_opcache;
 int co_opcache_flag; // used to determine when create a cache.
 unsigned char co_opcache_size; // length of co_opcache.
} PyCodeObject;

/* Masks for co_flags above */
#define CO_OPTIMIZED 0x0001
#define CO_NEWLOCALS 0x0002
#define CO_VARARGS 0x0004
#define CO_VARKEYWORDS 0x0008
#define CO_NESTED 0x0010
#define CO_GENERATOR 0x0020
/* The CO_NOFREE flag is set if there are no free or cell variables.
 This information is redundant, but it allows a single flag test
 to determine whether there is any extra work to be done when the
 call frame it setup.
*/
#define CO_NOFREE 0x0040

/* The CO_COROUTINE flag is set for coroutine functions (defined with
 ``async def`` keywords) */
#define CO_COROUTINE 0x0080
#define CO_ITERABLE_COROUTINE 0x0100
#define CO_ASYNC_GENERATOR 0x0200

/* bpo-39562: These constant values are changed in Python 3.9
 to prevent collision with compiler flags. CO_FUTURE_ and PyCF_
 constants must be kept unique. PyCF_ constants can use bits from
 0x0100 to 0x10000. CO_FUTURE_ constants use bits starting at 0x20000. */
#define CO_FUTURE_DIVISION 0x20000
#define CO_FUTURE_ABSOLUTE_IMPORT 0x40000 /* do absolute imports by default */
#define CO_FUTURE_WITH_STATEMENT 0x80000
#define CO_FUTURE_PRINT_FUNCTION 0x100000
#define CO_FUTURE_UNICODE_LITERALS 0x200000

#define CO_FUTURE_BARRY_AS_BDFL 0x400000
#define CO_FUTURE_GENERATOR_STOP 0x800000
#define CO_FUTURE_ANNOTATIONS 0x1000000

/* This value is found in the co_cell2arg array when the associated cell
 variable does not correspond to an argument. */
#define CO_CELL_NOT_AN_ARG (-1)

/* This should be defined if a future statement modifies the syntax.
 For example, when a keyword is added.
*/
#define PY_PARSER_REQUIRES_FUTURE_KEYWORD

#define CO_MAXBLOCKS 20 /* Max static block nesting within a function */

PyAPI_DATA(PyTypeObject) PyCode_Type;

#define PyCode_Check(op) (Py_TYPE(op) == &PyCode_Type)
#define PyCode_GetNumFree(op) (PyTuple_GET_SIZE((op)->co_freevars))

/* Public interface */
PyAPI_FUNC(PyCodeObject *) PyCode_New(
 int, int, int, int, int, PyObject *, PyObject *,
 PyObject *, PyObject *, PyObject *, PyObject *,
 PyObject *, PyObject *, int, PyObject *);

PyAPI_FUNC(PyCodeObject *) PyCode_NewWithPosOnlyArgs(
 int, int, int, int, int, int, PyObject *, PyObject *,
 PyObject *, PyObject *, PyObject *, PyObject *,
 PyObject *, PyObject *, int, PyObject *);
 /* same as struct above */

/* Creates a new empty code object with the specified source location. */
PyAPI_FUNC(PyCodeObject *)
PyCode_NewEmpty(const char *filename, const char *funcname, int firstlineno);

/* Return the line number associated with the specified bytecode index
 in this code object. If you just need the line number of a frame,
 use PyFrame_GetLineNumber() instead. */
PyAPI_FUNC(int) PyCode_Addr2Line(PyCodeObject *, int);

/* for internal use only */
typedef struct _addr_pair {
 int ap_lower;
 int ap_upper;
} PyAddrPair;

#ifndef Py_LIMITED_API
/* Update *bounds to describe the first and one-past-the-last instructions in the
 same line as lasti. Return the number of that line.
*/
PyAPI_FUNC(int) _PyCode_CheckLineNumber(PyCodeObject* co,
 int lasti, PyAddrPair *bounds);

/* Create a comparable key used to compare constants taking in account the
 * object type. It is used to make sure types are not coerced (e.g., float and
 * complex) _and_ to distinguish 0.0 from -0.0 e.g. on IEEE platforms
 *
 * Return (type(obj), obj, ...): a tuple with variable size (at least 2 items)
 * depending on the type and the value. The type is the first item to not
 * compare bytes and str which can raise a BytesWarning exception. */
PyAPI_FUNC(PyObject*) _PyCode_ConstantKey(PyObject *obj);
#endif

PyAPI_FUNC(PyObject*) PyCode_Optimize(PyObject *code, PyObject* consts,
 PyObject *names, PyObject *lnotab);


#ifndef Py_LIMITED_API
PyAPI_FUNC(int) _PyCode_GetExtra(PyObject *code, Py_ssize_t index,
 void **extra);
PyAPI_FUNC(int) _PyCode_SetExtra(PyObject *code, Py_ssize_t index,
 void *extra);
#endif

#ifdef __cplusplus
}
#endif
#endif /* !Py_CODE_H */
#endif /* Py_LIMITED_API */