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/*
* This file compiles an abstract syntax tree (AST) into Python bytecode.
*
* The primary entry point is PyAST_Compile(), which returns a
* PyCodeObject. The compiler makes several passes to build the code
* object:
* 1. Checks for future statements. See future.c
* 2. Builds a symbol table. See symtable.c.
* 3. Generate code for basic blocks. See compiler_mod() in this file.
* 4. Assemble the basic blocks into final code. See assemble() in
* this file.
* 5. Optimize the byte code (peephole optimizations). See peephole.c
*
* Note that compiler_mod() suggests module, but the module ast type
* (mod_ty) has cases for expressions and interactive statements.
*
* CAUTION: The VISIT_* macros abort the current function when they
* encounter a problem. So don't invoke them when there is memory
* which needs to be released. Code blocks are OK, as the compiler
* structure takes care of releasing those. Use the arena to manage
* objects.
*/
#include "Python.h"
#include "Python-ast.h"
#include "node.h"
#include "ast.h"
#include "code.h"
#include "symtable.h"
#include "opcode.h"
#include "wordcode_helpers.h"
#define DEFAULT_BLOCK_SIZE 16
#define DEFAULT_BLOCKS 8
#define DEFAULT_CODE_SIZE 128
#define DEFAULT_LNOTAB_SIZE 16
#define COMP_GENEXP 0
#define COMP_LISTCOMP 1
#define COMP_SETCOMP 2
#define COMP_DICTCOMP 3
struct instr {
unsigned i_jabs : 1;
unsigned i_jrel : 1;
unsigned char i_opcode;
int i_oparg;
struct basicblock_ *i_target; /* target block (if jump instruction) */
int i_lineno;
};
typedef struct basicblock_ {
/* Each basicblock in a compilation unit is linked via b_list in the
reverse order that the block are allocated. b_list points to the next
block, not to be confused with b_next, which is next by control flow. */
struct basicblock_ *b_list;
/* number of instructions used */
int b_iused;
/* length of instruction array (b_instr) */
int b_ialloc;
/* pointer to an array of instructions, initially NULL */
struct instr *b_instr;
/* If b_next is non-NULL, it is a pointer to the next
block reached by normal control flow. */
struct basicblock_ *b_next;
/* b_seen is used to perform a DFS of basicblocks. */
unsigned b_seen : 1;
/* b_return is true if a RETURN_VALUE opcode is inserted. */
unsigned b_return : 1;
/* depth of stack upon entry of block, computed by stackdepth() */
int b_startdepth;
/* instruction offset for block, computed by assemble_jump_offsets() */
int b_offset;
} basicblock;
/* fblockinfo tracks the current frame block.
A frame block is used to handle loops, try/except, and try/finally.
It's called a frame block to distinguish it from a basic block in the
compiler IR.
*/
enum fblocktype { WHILE_LOOP, FOR_LOOP, EXCEPT, FINALLY_TRY, FINALLY_END,
WITH, ASYNC_WITH, HANDLER_CLEANUP };
struct fblockinfo {
enum fblocktype fb_type;
basicblock *fb_block;
/* (optional) type-specific exit or cleanup block */
basicblock *fb_exit;
};
enum {
COMPILER_SCOPE_MODULE,
COMPILER_SCOPE_CLASS,
COMPILER_SCOPE_FUNCTION,
COMPILER_SCOPE_ASYNC_FUNCTION,
COMPILER_SCOPE_LAMBDA,
COMPILER_SCOPE_COMPREHENSION,
};
/* The following items change on entry and exit of code blocks.
They must be saved and restored when returning to a block.
*/
struct compiler_unit {
PySTEntryObject *u_ste;
PyObject *u_name;
PyObject *u_qualname; /* dot-separated qualified name (lazy) */
int u_scope_type;
/* The following fields are dicts that map objects to
the index of them in co_XXX. The index is used as
the argument for opcodes that refer to those collections.
*/
PyObject *u_consts; /* all constants */
PyObject *u_names; /* all names */
PyObject *u_varnames; /* local variables */
PyObject *u_cellvars; /* cell variables */
PyObject *u_freevars; /* free variables */
PyObject *u_private; /* for private name mangling */
Py_ssize_t u_argcount; /* number of arguments for block */
Py_ssize_t u_kwonlyargcount; /* number of keyword only arguments for block */
/* Pointer to the most recently allocated block. By following b_list
members, you can reach all early allocated blocks. */
basicblock *u_blocks;
basicblock *u_curblock; /* pointer to current block */
int u_nfblocks;
struct fblockinfo u_fblock[CO_MAXBLOCKS];
int u_firstlineno; /* the first lineno of the block */
int u_lineno; /* the lineno for the current stmt */
int u_col_offset; /* the offset of the current stmt */
int u_lineno_set; /* boolean to indicate whether instr
has been generated with current lineno */
};
/* This struct captures the global state of a compilation.
The u pointer points to the current compilation unit, while units
for enclosing blocks are stored in c_stack. The u and c_stack are
managed by compiler_enter_scope() and compiler_exit_scope().
Note that we don't track recursion levels during compilation - the
task of detecting and rejecting excessive levels of nesting is
handled by the symbol analysis pass.
*/
struct compiler {
PyObject *c_filename;
struct symtable *c_st;
PyFutureFeatures *c_future; /* pointer to module's __future__ */
PyCompilerFlags *c_flags;
int c_optimize; /* optimization level */
int c_interactive; /* true if in interactive mode */
int c_nestlevel;
struct compiler_unit *u; /* compiler state for current block */
PyObject *c_stack; /* Python list holding compiler_unit ptrs */
PyArena *c_arena; /* pointer to memory allocation arena */
};
static int compiler_enter_scope(struct compiler *, identifier, int, void *, int);
static void compiler_free(struct compiler *);
static basicblock *compiler_new_block(struct compiler *);
static int compiler_next_instr(struct compiler *, basicblock *);
static int compiler_addop(struct compiler *, int);
static int compiler_addop_i(struct compiler *, int, Py_ssize_t);
static int compiler_addop_j(struct compiler *, int, basicblock *, int);
static int compiler_error(struct compiler *, const char *);
static int compiler_nameop(struct compiler *, identifier, expr_context_ty);
static PyCodeObject *compiler_mod(struct compiler *, mod_ty);
static int compiler_visit_stmt(struct compiler *, stmt_ty);
static int compiler_visit_keyword(struct compiler *, keyword_ty);
static int compiler_visit_expr(struct compiler *, expr_ty);
static int compiler_augassign(struct compiler *, stmt_ty);
static int compiler_annassign(struct compiler *, stmt_ty);
static int compiler_visit_slice(struct compiler *, slice_ty,
expr_context_ty);
static int inplace_binop(struct compiler *, operator_ty);
static int expr_constant(expr_ty);
static int compiler_with(struct compiler *, stmt_ty, int);
static int compiler_async_with(struct compiler *, stmt_ty, int);
static int compiler_async_for(struct compiler *, stmt_ty);
static int compiler_call_helper(struct compiler *c, int n,
asdl_seq *args,
asdl_seq *keywords);
static int compiler_try_except(struct compiler *, stmt_ty);
static int compiler_set_qualname(struct compiler *);
static int compiler_sync_comprehension_generator(
struct compiler *c,
asdl_seq *generators, int gen_index,
expr_ty elt, expr_ty val, int type);
static int compiler_async_comprehension_generator(
struct compiler *c,
asdl_seq *generators, int gen_index,
expr_ty elt, expr_ty val, int type);
static PyCodeObject *assemble(struct compiler *, int addNone);
static PyObject *__doc__, *__annotations__;
#define CAPSULE_NAME "compile.c compiler unit"
PyObject *
_Py_Mangle(PyObject *privateobj, PyObject *ident)
{
/* Name mangling: __private becomes _classname__private.
This is independent from how the name is used. */
PyObject *result;
size_t nlen, plen, ipriv;
Py_UCS4 maxchar;
if (privateobj == NULL || !PyUnicode_Check(privateobj) ||
PyUnicode_READ_CHAR(ident, 0) != '_' ||
PyUnicode_READ_CHAR(ident, 1) != '_') {
Py_INCREF(ident);
return ident;
}
nlen = PyUnicode_GET_LENGTH(ident);
plen = PyUnicode_GET_LENGTH(privateobj);
/* Don't mangle __id__ or names with dots.
The only time a name with a dot can occur is when
we are compiling an import statement that has a
package name.
TODO(jhylton): Decide whether we want to support
mangling of the module name, e.g. __M.X.
*/
if ((PyUnicode_READ_CHAR(ident, nlen-1) == '_' &&
PyUnicode_READ_CHAR(ident, nlen-2) == '_') ||
PyUnicode_FindChar(ident, '.', 0, nlen, 1) != -1) {
Py_INCREF(ident);
return ident; /* Don't mangle __whatever__ */
}
/* Strip leading underscores from class name */
ipriv = 0;
while (PyUnicode_READ_CHAR(privateobj, ipriv) == '_')
ipriv++;
if (ipriv == plen) {
Py_INCREF(ident);
return ident; /* Don't mangle if class is just underscores */
}
plen -= ipriv;
if (plen + nlen >= PY_SSIZE_T_MAX - 1) {
PyErr_SetString(PyExc_OverflowError,
"private identifier too large to be mangled");
return NULL;
}
maxchar = PyUnicode_MAX_CHAR_VALUE(ident);
if (PyUnicode_MAX_CHAR_VALUE(privateobj) > maxchar)
maxchar = PyUnicode_MAX_CHAR_VALUE(privateobj);
result = PyUnicode_New(1 + nlen + plen, maxchar);
if (!result)
return 0;
/* ident = "_" + priv[ipriv:] + ident # i.e. 1+plen+nlen bytes */
PyUnicode_WRITE(PyUnicode_KIND(result), PyUnicode_DATA(result), 0, '_');
if (PyUnicode_CopyCharacters(result, 1, privateobj, ipriv, plen) < 0) {
Py_DECREF(result);
return NULL;
}
if (PyUnicode_CopyCharacters(result, plen+1, ident, 0, nlen) < 0) {
Py_DECREF(result);
return NULL;
}
assert(_PyUnicode_CheckConsistency(result, 1));
return result;
}
static int
compiler_init(struct compiler *c)
{
memset(c, 0, sizeof(struct compiler));
c->c_stack = PyList_New(0);
if (!c->c_stack)
return 0;
return 1;
}
PyCodeObject *
PyAST_CompileObject(mod_ty mod, PyObject *filename, PyCompilerFlags *flags,
int optimize, PyArena *arena)
{
struct compiler c;
PyCodeObject *co = NULL;
PyCompilerFlags local_flags;
int merged;
if (!__doc__) {
__doc__ = PyUnicode_InternFromString("__doc__");
if (!__doc__)
return NULL;
}
if (!__annotations__) {
__annotations__ = PyUnicode_InternFromString("__annotations__");
if (!__annotations__)
return NULL;
}
if (!compiler_init(&c))
return NULL;
Py_INCREF(filename);
c.c_filename = filename;
c.c_arena = arena;
c.c_future = PyFuture_FromASTObject(mod, filename);
if (c.c_future == NULL)
goto finally;
if (!flags) {
local_flags.cf_flags = 0;
flags = &local_flags;
}
merged = c.c_future->ff_features | flags->cf_flags;
c.c_future->ff_features = merged;
flags->cf_flags = merged;
c.c_flags = flags;
c.c_optimize = (optimize == -1) ? Py_OptimizeFlag : optimize;
c.c_nestlevel = 0;
if (!_PyAST_Optimize(mod, arena, c.c_optimize)) {
goto finally;
}
c.c_st = PySymtable_BuildObject(mod, filename, c.c_future);
if (c.c_st == NULL) {
if (!PyErr_Occurred())
PyErr_SetString(PyExc_SystemError, "no symtable");
goto finally;
}
co = compiler_mod(&c, mod);
finally:
compiler_free(&c);
assert(co || PyErr_Occurred());
return co;
}
PyCodeObject *
PyAST_CompileEx(mod_ty mod, const char *filename_str, PyCompilerFlags *flags,
int optimize, PyArena *arena)
{
PyObject *filename;
PyCodeObject *co;
filename = PyUnicode_DecodeFSDefault(filename_str);
if (filename == NULL)
return NULL;
co = PyAST_CompileObject(mod, filename, flags, optimize, arena);
Py_DECREF(filename);
return co;
}
PyCodeObject *
PyNode_Compile(struct _node *n, const char *filename)
{
PyCodeObject *co = NULL;
mod_ty mod;
PyArena *arena = PyArena_New();
if (!arena)
return NULL;
mod = PyAST_FromNode(n, NULL, filename, arena);
if (mod)
co = PyAST_Compile(mod, filename, NULL, arena);
PyArena_Free(arena);
return co;
}
static void
compiler_free(struct compiler *c)
{
if (c->c_st)
PySymtable_Free(c->c_st);
if (c->c_future)
PyObject_Free(c->c_future);
Py_XDECREF(c->c_filename);
Py_DECREF(c->c_stack);
}
static PyObject *
list2dict(PyObject *list)
{
Py_ssize_t i, n;
PyObject *v, *k;
PyObject *dict = PyDict_New();
if (!dict) return NULL;
n = PyList_Size(list);
for (i = 0; i < n; i++) {
v = PyLong_FromSsize_t(i);
if (!v) {
Py_DECREF(dict);
return NULL;
}
k = PyList_GET_ITEM(list, i);
if (PyDict_SetItem(dict, k, v) < 0) {
Py_DECREF(v);
Py_DECREF(dict);
return NULL;
}
Py_DECREF(v);
}
return dict;
}
/* Return new dict containing names from src that match scope(s).
src is a symbol table dictionary. If the scope of a name matches
either scope_type or flag is set, insert it into the new dict. The
values are integers, starting at offset and increasing by one for
each key.
*/
static PyObject *
dictbytype(PyObject *src, int scope_type, int flag, Py_ssize_t offset)
{
Py_ssize_t i = offset, scope, num_keys, key_i;
PyObject *k, *v, *dest = PyDict_New();
PyObject *sorted_keys;
assert(offset >= 0);
if (dest == NULL)
return NULL;
/* Sort the keys so that we have a deterministic order on the indexes
saved in the returned dictionary. These indexes are used as indexes
into the free and cell var storage. Therefore if they aren't
deterministic, then the generated bytecode is not deterministic.
*/
sorted_keys = PyDict_Keys(src);
if (sorted_keys == NULL)
return NULL;
if (PyList_Sort(sorted_keys) != 0) {
Py_DECREF(sorted_keys);
return NULL;
}
num_keys = PyList_GET_SIZE(sorted_keys);
for (key_i = 0; key_i < num_keys; key_i++) {
/* XXX this should probably be a macro in symtable.h */
long vi;
k = PyList_GET_ITEM(sorted_keys, key_i);
v = PyDict_GetItem(src, k);
assert(PyLong_Check(v));
vi = PyLong_AS_LONG(v);
scope = (vi >> SCOPE_OFFSET) & SCOPE_MASK;
if (scope == scope_type || vi & flag) {
PyObject *item = PyLong_FromSsize_t(i);
if (item == NULL) {
Py_DECREF(sorted_keys);
Py_DECREF(dest);
return NULL;
}
i++;
if (PyDict_SetItem(dest, k, item) < 0) {
Py_DECREF(sorted_keys);
Py_DECREF(item);
Py_DECREF(dest);
return NULL;
}
Py_DECREF(item);
}
}
Py_DECREF(sorted_keys);
return dest;
}
static void
compiler_unit_check(struct compiler_unit *u)
{
basicblock *block;
for (block = u->u_blocks; block != NULL; block = block->b_list) {
assert((uintptr_t)block != 0xcbcbcbcbU);
assert((uintptr_t)block != 0xfbfbfbfbU);
assert((uintptr_t)block != 0xdbdbdbdbU);
if (block->b_instr != NULL) {
assert(block->b_ialloc > 0);
assert(block->b_iused > 0);
assert(block->b_ialloc >= block->b_iused);
}
else {
assert (block->b_iused == 0);
assert (block->b_ialloc == 0);
}
}
}
static void
compiler_unit_free(struct compiler_unit *u)
{
basicblock *b, *next;
compiler_unit_check(u);
b = u->u_blocks;
while (b != NULL) {
if (b->b_instr)
PyObject_Free((void *)b->b_instr);
next = b->b_list;
PyObject_Free((void *)b);
b = next;
}
Py_CLEAR(u->u_ste);
Py_CLEAR(u->u_name);
Py_CLEAR(u->u_qualname);
Py_CLEAR(u->u_consts);
Py_CLEAR(u->u_names);
Py_CLEAR(u->u_varnames);
Py_CLEAR(u->u_freevars);
Py_CLEAR(u->u_cellvars);
Py_CLEAR(u->u_private);
PyObject_Free(u);
}
static int
compiler_enter_scope(struct compiler *c, identifier name,
int scope_type, void *key, int lineno)
{
struct compiler_unit *u;
basicblock *block;
u = (struct compiler_unit *)PyObject_Malloc(sizeof(
struct compiler_unit));
if (!u) {
PyErr_NoMemory();
return 0;
}
memset(u, 0, sizeof(struct compiler_unit));
u->u_scope_type = scope_type;
u->u_argcount = 0;
u->u_kwonlyargcount = 0;
u->u_ste = PySymtable_Lookup(c->c_st, key);
if (!u->u_ste) {
compiler_unit_free(u);
return 0;
}
Py_INCREF(name);
u->u_name = name;
u->u_varnames = list2dict(u->u_ste->ste_varnames);
u->u_cellvars = dictbytype(u->u_ste->ste_symbols, CELL, 0, 0);
if (!u->u_varnames || !u->u_cellvars) {
compiler_unit_free(u);
return 0;
}
if (u->u_ste->ste_needs_class_closure) {
/* Cook up an implicit __class__ cell. */
_Py_IDENTIFIER(__class__);
PyObject *name;
int res;
assert(u->u_scope_type == COMPILER_SCOPE_CLASS);
assert(PyDict_GET_SIZE(u->u_cellvars) == 0);
name = _PyUnicode_FromId(&PyId___class__);
if (!name) {
compiler_unit_free(u);
return 0;
}
res = PyDict_SetItem(u->u_cellvars, name, _PyLong_Zero);
if (res < 0) {
compiler_unit_free(u);
return 0;
}
}
u->u_freevars = dictbytype(u->u_ste->ste_symbols, FREE, DEF_FREE_CLASS,
PyDict_GET_SIZE(u->u_cellvars));
if (!u->u_freevars) {
compiler_unit_free(u);
return 0;
}
u->u_blocks = NULL;
u->u_nfblocks = 0;
u->u_firstlineno = lineno;
u->u_lineno = 0;
u->u_col_offset = 0;
u->u_lineno_set = 0;
u->u_consts = PyDict_New();
if (!u->u_consts) {
compiler_unit_free(u);
return 0;
}
u->u_names = PyDict_New();
if (!u->u_names) {
compiler_unit_free(u);
return 0;
}
u->u_private = NULL;
/* Push the old compiler_unit on the stack. */
if (c->u) {
PyObject *capsule = PyCapsule_New(c->u, CAPSULE_NAME, NULL);
if (!capsule || PyList_Append(c->c_stack, capsule) < 0) {
Py_XDECREF(capsule);
compiler_unit_free(u);
return 0;
}
Py_DECREF(capsule);
u->u_private = c->u->u_private;
Py_XINCREF(u->u_private);
}
c->u = u;
c->c_nestlevel++;
block = compiler_new_block(c);
if (block == NULL)
return 0;
c->u->u_curblock = block;
if (u->u_scope_type != COMPILER_SCOPE_MODULE) {
if (!compiler_set_qualname(c))
return 0;
}
return 1;
}
static void
compiler_exit_scope(struct compiler *c)
{
Py_ssize_t n;
PyObject *capsule;
c->c_nestlevel--;
compiler_unit_free(c->u);
/* Restore c->u to the parent unit. */
n = PyList_GET_SIZE(c->c_stack) - 1;
if (n >= 0) {
capsule = PyList_GET_ITEM(c->c_stack, n);
c->u = (struct compiler_unit *)PyCapsule_GetPointer(capsule, CAPSULE_NAME);
assert(c->u);
/* we are deleting from a list so this really shouldn't fail */
if (PySequence_DelItem(c->c_stack, n) < 0)
Py_FatalError("compiler_exit_scope()");
compiler_unit_check(c->u);
}
else
c->u = NULL;
}
static int
compiler_set_qualname(struct compiler *c)
{
_Py_static_string(dot, ".");
_Py_static_string(dot_locals, ".<locals>");
Py_ssize_t stack_size;
struct compiler_unit *u = c->u;
PyObject *name, *base, *dot_str, *dot_locals_str;
base = NULL;
stack_size = PyList_GET_SIZE(c->c_stack);
assert(stack_size >= 1);
if (stack_size > 1) {
int scope, force_global = 0;
struct compiler_unit *parent;
PyObject *mangled, *capsule;
capsule = PyList_GET_ITEM(c->c_stack, stack_size - 1);
parent = (struct compiler_unit *)PyCapsule_GetPointer(capsule, CAPSULE_NAME);
assert(parent);
if (u->u_scope_type == COMPILER_SCOPE_FUNCTION
|| u->u_scope_type == COMPILER_SCOPE_ASYNC_FUNCTION
|| u->u_scope_type == COMPILER_SCOPE_CLASS) {
assert(u->u_name);
mangled = _Py_Mangle(parent->u_private, u->u_name);
if (!mangled)
return 0;
scope = PyST_GetScope(parent->u_ste, mangled);
Py_DECREF(mangled);
assert(scope != GLOBAL_IMPLICIT);
if (scope == GLOBAL_EXPLICIT)
force_global = 1;
}
if (!force_global) {
if (parent->u_scope_type == COMPILER_SCOPE_FUNCTION
|| parent->u_scope_type == COMPILER_SCOPE_ASYNC_FUNCTION
|| parent->u_scope_type == COMPILER_SCOPE_LAMBDA) {
dot_locals_str = _PyUnicode_FromId(&dot_locals);
if (dot_locals_str == NULL)
return 0;
base = PyUnicode_Concat(parent->u_qualname, dot_locals_str);
if (base == NULL)
return 0;
}
else {
Py_INCREF(parent->u_qualname);
base = parent->u_qualname;
}
}
}
if (base != NULL) {
dot_str = _PyUnicode_FromId(&dot);
if (dot_str == NULL) {
Py_DECREF(base);
return 0;
}
name = PyUnicode_Concat(base, dot_str);
Py_DECREF(base);
if (name == NULL)
return 0;
PyUnicode_Append(&name, u->u_name);
if (name == NULL)
return 0;
}
else {
Py_INCREF(u->u_name);
name = u->u_name;
}
u->u_qualname = name;
return 1;
}
/* Allocate a new block and return a pointer to it.
Returns NULL on error.
*/
static basicblock *
compiler_new_block(struct compiler *c)
{
basicblock *b;
struct compiler_unit *u;
u = c->u;
b = (basicblock *)PyObject_Malloc(sizeof(basicblock));
if (b == NULL) {
PyErr_NoMemory();
return NULL;
}
memset((void *)b, 0, sizeof(basicblock));
/* Extend the singly linked list of blocks with new block. */
b->b_list = u->u_blocks;
u->u_blocks = b;
return b;
}
static basicblock *
compiler_next_block(struct compiler *c)
{
basicblock *block = compiler_new_block(c);
if (block == NULL)
return NULL;
c->u->u_curblock->b_next = block;
c->u->u_curblock = block;
return block;
}
static basicblock *
compiler_use_next_block(struct compiler *c, basicblock *block)
{
assert(block != NULL);
c->u->u_curblock->b_next = block;
c->u->u_curblock = block;
return block;
}
/* Returns the offset of the next instruction in the current block's
b_instr array. Resizes the b_instr as necessary.
Returns -1 on failure.
*/
static int
compiler_next_instr(struct compiler *c, basicblock *b)
{
assert(b != NULL);
if (b->b_instr == NULL) {
b->b_instr = (struct instr *)PyObject_Malloc(
sizeof(struct instr) * DEFAULT_BLOCK_SIZE);
if (b->b_instr == NULL) {
PyErr_NoMemory();
return -1;
}
b->b_ialloc = DEFAULT_BLOCK_SIZE;
memset((char *)b->b_instr, 0,
sizeof(struct instr) * DEFAULT_BLOCK_SIZE);
}
else if (b->b_iused == b->b_ialloc) {
struct instr *tmp;
size_t oldsize, newsize;
oldsize = b->b_ialloc * sizeof(struct instr);
newsize = oldsize << 1;
if (oldsize > (SIZE_MAX >> 1)) {
PyErr_NoMemory();
return -1;
}
if (newsize == 0) {
PyErr_NoMemory();
return -1;
}
b->b_ialloc <<= 1;
tmp = (struct instr *)PyObject_Realloc(
(void *)b->b_instr, newsize);
if (tmp == NULL) {
PyErr_NoMemory();
return -1;
}
b->b_instr = tmp;
memset((char *)b->b_instr + oldsize, 0, newsize - oldsize);
}
return b->b_iused++;
}
/* Set the i_lineno member of the instruction at offset off if the
line number for the current expression/statement has not
already been set. If it has been set, the call has no effect.
The line number is reset in the following cases:
- when entering a new scope
- on each statement
- on each expression that start a new line
- before the "except" and "finally" clauses
- before the "for" and "while" expressions
*/
static void
compiler_set_lineno(struct compiler *c, int off)
{
basicblock *b;
if (c->u->u_lineno_set)
return;
c->u->u_lineno_set = 1;
b = c->u->u_curblock;
b->b_instr[off].i_lineno = c->u->u_lineno;
}
/* Return the stack effect of opcode with argument oparg.
Some opcodes have different stack effect when jump to the target and
when not jump. The 'jump' parameter specifies the case:
* 0 -- when not jump
* 1 -- when jump
* -1 -- maximal
*/
/* XXX Make the stack effect of WITH_CLEANUP_START and
WITH_CLEANUP_FINISH deterministic. */
static int
stack_effect(int opcode, int oparg, int jump)
{
switch (opcode) {
case NOP:
case EXTENDED_ARG:
return 0;
/* Stack manipulation */
case POP_TOP:
return -1;
case ROT_TWO:
case ROT_THREE:
case ROT_FOUR:
return 0;
case DUP_TOP:
return 1;
case DUP_TOP_TWO:
return 2;
/* Unary operators */
case UNARY_POSITIVE:
case UNARY_NEGATIVE:
case UNARY_NOT:
case UNARY_INVERT:
return 0;
case SET_ADD:
case LIST_APPEND:
return -1;
case MAP_ADD:
return -2;
/* Binary operators */
case BINARY_POWER:
case BINARY_MULTIPLY:
case BINARY_MATRIX_MULTIPLY:
case BINARY_MODULO:
case BINARY_ADD:
case BINARY_SUBTRACT:
case BINARY_SUBSCR:
case BINARY_FLOOR_DIVIDE:
case BINARY_TRUE_DIVIDE:
return -1;
case INPLACE_FLOOR_DIVIDE:
case INPLACE_TRUE_DIVIDE:
return -1;
case INPLACE_ADD:
case INPLACE_SUBTRACT:
case INPLACE_MULTIPLY:
case INPLACE_MATRIX_MULTIPLY:
case INPLACE_MODULO:
return -1;
case STORE_SUBSCR:
return -3;
case DELETE_SUBSCR:
return -2;
case BINARY_LSHIFT:
case BINARY_RSHIFT:
case BINARY_AND:
case BINARY_XOR:
case BINARY_OR:
return -1;
case INPLACE_POWER:
return -1;
case GET_ITER:
return 0;
case PRINT_EXPR:
return -1;
case LOAD_BUILD_CLASS:
return 1;
case INPLACE_LSHIFT:
case INPLACE_RSHIFT:
case INPLACE_AND:
case INPLACE_XOR:
case INPLACE_OR:
return -1;
case SETUP_WITH:
/* 1 in the normal flow.
* Restore the stack position and push 6 values before jumping to
* the handler if an exception be raised. */
return jump ? 6 : 1;
case WITH_CLEANUP_START:
return 2; /* or 1, depending on TOS */
case WITH_CLEANUP_FINISH:
/* Pop a variable number of values pushed by WITH_CLEANUP_START
* + __exit__ or __aexit__. */
return -3;
case RETURN_VALUE:
return -1;
case IMPORT_STAR:
return -1;
case SETUP_ANNOTATIONS:
return 0;
case YIELD_VALUE:
return 0;
case YIELD_FROM:
return -1;
case POP_BLOCK:
return 0;
case POP_EXCEPT:
return -3;
case END_FINALLY:
case POP_FINALLY:
/* Pop 6 values when an exception was raised. */
return -6;
case STORE_NAME:
return -1;
case DELETE_NAME:
return 0;
case UNPACK_SEQUENCE:
return oparg-1;
case UNPACK_EX:
return (oparg&0xFF) + (oparg>>8);
case FOR_ITER:
/* -1 at end of iterator, 1 if continue iterating. */
return jump > 0 ? -1 : 1;
case STORE_ATTR:
return -2;
case DELETE_ATTR:
return -1;
case STORE_GLOBAL:
return -1;
case DELETE_GLOBAL:
return 0;
case LOAD_CONST:
return 1;
case LOAD_NAME:
return 1;
case BUILD_TUPLE:
case BUILD_LIST:
case BUILD_SET:
case BUILD_STRING:
return 1-oparg;
case BUILD_LIST_UNPACK:
case BUILD_TUPLE_UNPACK:
case BUILD_TUPLE_UNPACK_WITH_CALL:
case BUILD_SET_UNPACK:
case BUILD_MAP_UNPACK:
case BUILD_MAP_UNPACK_WITH_CALL:
return 1 - oparg;
case BUILD_MAP:
return 1 - 2*oparg;
case BUILD_CONST_KEY_MAP:
return -oparg;
case LOAD_ATTR:
return 0;
case COMPARE_OP:
return -1;
case IMPORT_NAME:
return -1;
case IMPORT_FROM:
return 1;
/* Jumps */
case JUMP_FORWARD:
case JUMP_ABSOLUTE:
return 0;
case JUMP_IF_TRUE_OR_POP:
case JUMP_IF_FALSE_OR_POP:
return jump ? 0 : -1;
case POP_JUMP_IF_FALSE:
case POP_JUMP_IF_TRUE:
return -1;
case LOAD_GLOBAL:
return 1;
/* Exception handling */
case SETUP_FINALLY:
/* 0 in the normal flow.
* Restore the stack position and push 6 values before jumping to
* the handler if an exception be raised. */
return jump ? 6 : 0;
case BEGIN_FINALLY:
/* Actually pushes 1 value, but count 6 for balancing with
* END_FINALLY and POP_FINALLY.
* This is the main reason of using this opcode instead of
* "LOAD_CONST None". */
return 6;
case CALL_FINALLY:
return jump ? 1 : 0;
case LOAD_FAST:
return 1;
case STORE_FAST:
return -1;
case DELETE_FAST:
return 0;
case RAISE_VARARGS:
return -oparg;
/* Functions and calls */
case CALL_FUNCTION:
return -oparg;
case CALL_METHOD:
return -oparg-1;
case CALL_FUNCTION_KW:
return -oparg-1;
case CALL_FUNCTION_EX:
return -1 - ((oparg & 0x01) != 0);
case MAKE_FUNCTION:
return -1 - ((oparg & 0x01) != 0) - ((oparg & 0x02) != 0) -
((oparg & 0x04) != 0) - ((oparg & 0x08) != 0);
case BUILD_SLICE:
if (oparg == 3)
return -2;
else
return -1;
/* Closures */
case LOAD_CLOSURE:
return 1;
case LOAD_DEREF:
case LOAD_CLASSDEREF:
return 1;
case STORE_DEREF:
return -1;
case DELETE_DEREF:
return 0;
/* Iterators and generators */
case GET_AWAITABLE:
return 0;
case SETUP_ASYNC_WITH:
/* 0 in the normal flow.
* Restore the stack position to the position before the result
* of __aenter__ and push 6 values before jumping to the handler
* if an exception be raised. */
return jump ? -1 + 6 : 0;
case BEFORE_ASYNC_WITH:
return 1;
case GET_AITER:
return 0;
case GET_ANEXT:
return 1;
case GET_YIELD_FROM_ITER:
return 0;
case END_ASYNC_FOR:
return -7;
case FORMAT_VALUE:
/* If there's a fmt_spec on the stack, we go from 2->1,
else 1->1. */
return (oparg & FVS_MASK) == FVS_HAVE_SPEC ? -1 : 0;
case LOAD_METHOD:
return 1;
default:
return PY_INVALID_STACK_EFFECT;
}
return PY_INVALID_STACK_EFFECT; /* not reachable */
}
int
PyCompile_OpcodeStackEffect(int opcode, int oparg)
{
return stack_effect(opcode, oparg, -1);
}
/* Add an opcode with no argument.
Returns 0 on failure, 1 on success.
*/
static int
compiler_addop(struct compiler *c, int opcode)
{
basicblock *b;
struct instr *i;
int off;
assert(!HAS_ARG(opcode));
off = compiler_next_instr(c, c->u->u_curblock);
if (off < 0)
return 0;
b = c->u->u_curblock;
i = &b->b_instr[off];
i->i_opcode = opcode;
i->i_oparg = 0;
if (opcode == RETURN_VALUE)
b->b_return = 1;
compiler_set_lineno(c, off);
return 1;
}
static Py_ssize_t
compiler_add_o(struct compiler *c, PyObject *dict, PyObject *o)
{
PyObject *v;
Py_ssize_t arg;
v = PyDict_GetItemWithError(dict, o);
if (!v) {
if (PyErr_Occurred()) {
return -1;
}
arg = PyDict_GET_SIZE(dict);
v = PyLong_FromSsize_t(arg);
if (!v) {
return -1;
}
if (PyDict_SetItem(dict, o, v) < 0) {
Py_DECREF(v);
return -1;
}
Py_DECREF(v);
}
else
arg = PyLong_AsLong(v);
return arg;
}
static Py_ssize_t
compiler_add_const(struct compiler *c, PyObject *o)
{
PyObject *t;
Py_ssize_t arg;
t = _PyCode_ConstantKey(o);
if (t == NULL)
return -1;
arg = compiler_add_o(c, c->u->u_consts, t);
Py_DECREF(t);
return arg;
}
static int
compiler_addop_load_const(struct compiler *c, PyObject *o)
{
Py_ssize_t arg = compiler_add_const(c, o);
if (arg < 0)
return 0;
return compiler_addop_i(c, LOAD_CONST, arg);
}
static int
compiler_addop_o(struct compiler *c, int opcode, PyObject *dict,
PyObject *o)
{
Py_ssize_t arg = compiler_add_o(c, dict, o);
if (arg < 0)
return 0;
return compiler_addop_i(c, opcode, arg);
}
static int
compiler_addop_name(struct compiler *c, int opcode, PyObject *dict,
PyObject *o)
{
Py_ssize_t arg;
PyObject *mangled = _Py_Mangle(c->u->u_private, o);
if (!mangled)
return 0;
arg = compiler_add_o(c, dict, mangled);
Py_DECREF(mangled);
if (arg < 0)
return 0;
return compiler_addop_i(c, opcode, arg);
}
/* Add an opcode with an integer argument.
Returns 0 on failure, 1 on success.
*/
static int
compiler_addop_i(struct compiler *c, int opcode, Py_ssize_t oparg)
{
struct instr *i;
int off;
/* oparg value is unsigned, but a signed C int is usually used to store
it in the C code (like Python/ceval.c).
Limit to 32-bit signed C int (rather than INT_MAX) for portability.
The argument of a concrete bytecode instruction is limited to 8-bit.
EXTENDED_ARG is used for 16, 24, and 32-bit arguments. */
assert(HAS_ARG(opcode));
assert(0 <= oparg && oparg <= 2147483647);
off = compiler_next_instr(c, c->u->u_curblock);
if (off < 0)
return 0;
i = &c->u->u_curblock->b_instr[off];
i->i_opcode = opcode;
i->i_oparg = Py_SAFE_DOWNCAST(oparg, Py_ssize_t, int);
compiler_set_lineno(c, off);
return 1;
}
static int
compiler_addop_j(struct compiler *c, int opcode, basicblock *b, int absolute)
{
struct instr *i;
int off;
assert(HAS_ARG(opcode));
assert(b != NULL);
off = compiler_next_instr(c, c->u->u_curblock);
if (off < 0)
return 0;
i = &c->u->u_curblock->b_instr[off];
i->i_opcode = opcode;
i->i_target = b;
if (absolute)
i->i_jabs = 1;
else
i->i_jrel = 1;
compiler_set_lineno(c, off);
return 1;
}
/* NEXT_BLOCK() creates an implicit jump from the current block
to the new block.
The returns inside this macro make it impossible to decref objects
created in the local function. Local objects should use the arena.
*/
#define NEXT_BLOCK(C) { \
if (compiler_next_block((C)) == NULL) \
return 0; \
}
#define ADDOP(C, OP) { \
if (!compiler_addop((C), (OP))) \
return 0; \
}
#define ADDOP_IN_SCOPE(C, OP) { \
if (!compiler_addop((C), (OP))) { \
compiler_exit_scope(c); \
return 0; \
} \
}
#define ADDOP_LOAD_CONST(C, O) { \
if (!compiler_addop_load_const((C), (O))) \
return 0; \
}
/* Same as ADDOP_LOAD_CONST, but steals a reference. */
#define ADDOP_LOAD_CONST_NEW(C, O) { \
PyObject *__new_const = (O); \
if (__new_const == NULL) { \
return 0; \
} \
if (!compiler_addop_load_const((C), __new_const)) { \
Py_DECREF(__new_const); \
return 0; \
} \
Py_DECREF(__new_const); \
}
#define ADDOP_O(C, OP, O, TYPE) { \
if (!compiler_addop_o((C), (OP), (C)->u->u_ ## TYPE, (O))) \
return 0; \
}
/* Same as ADDOP_O, but steals a reference. */
#define ADDOP_N(C, OP, O, TYPE) { \
if (!compiler_addop_o((C), (OP), (C)->u->u_ ## TYPE, (O))) { \
Py_DECREF((O)); \
return 0; \
} \
Py_DECREF((O)); \
}
#define ADDOP_NAME(C, OP, O, TYPE) { \
if (!compiler_addop_name((C), (OP), (C)->u->u_ ## TYPE, (O))) \
return 0; \
}
#define ADDOP_I(C, OP, O) { \
if (!compiler_addop_i((C), (OP), (O))) \
return 0; \
}
#define ADDOP_JABS(C, OP, O) { \
if (!compiler_addop_j((C), (OP), (O), 1)) \
return 0; \
}
#define ADDOP_JREL(C, OP, O) { \
if (!compiler_addop_j((C), (OP), (O), 0)) \
return 0; \
}
/* VISIT and VISIT_SEQ takes an ASDL type as their second argument. They use
the ASDL name to synthesize the name of the C type and the visit function.
*/
#define VISIT(C, TYPE, V) {\
if (!compiler_visit_ ## TYPE((C), (V))) \
return 0; \
}
#define VISIT_IN_SCOPE(C, TYPE, V) {\
if (!compiler_visit_ ## TYPE((C), (V))) { \
compiler_exit_scope(c); \
return 0; \
} \
}
#define VISIT_SLICE(C, V, CTX) {\
if (!compiler_visit_slice((C), (V), (CTX))) \
return 0; \
}
#define VISIT_SEQ(C, TYPE, SEQ) { \
int _i; \
asdl_seq *seq = (SEQ); /* avoid variable capture */ \
for (_i = 0; _i < asdl_seq_LEN(seq); _i++) { \
TYPE ## _ty elt = (TYPE ## _ty)asdl_seq_GET(seq, _i); \
if (!compiler_visit_ ## TYPE((C), elt)) \
return 0; \
} \
}
#define VISIT_SEQ_IN_SCOPE(C, TYPE, SEQ) { \
int _i; \
asdl_seq *seq = (SEQ); /* avoid variable capture */ \
for (_i = 0; _i < asdl_seq_LEN(seq); _i++) { \
TYPE ## _ty elt = (TYPE ## _ty)asdl_seq_GET(seq, _i); \
if (!compiler_visit_ ## TYPE((C), elt)) { \
compiler_exit_scope(c); \
return 0; \
} \
} \
}
static int
is_const(expr_ty e)
{
switch (e->kind) {
case Constant_kind:
case Num_kind:
case Str_kind:
case Bytes_kind:
case Ellipsis_kind:
case NameConstant_kind:
return 1;
default:
return 0;
}
}
static PyObject *
get_const_value(expr_ty e)
{
switch (e->kind) {
case Constant_kind:
return e->v.Constant.value;
case Num_kind:
return e->v.Num.n;
case Str_kind:
return e->v.Str.s;
case Bytes_kind:
return e->v.Bytes.s;
case Ellipsis_kind:
return Py_Ellipsis;
case NameConstant_kind:
return e->v.NameConstant.value;
default:
Py_UNREACHABLE();
}
}
/* Search if variable annotations are present statically in a block. */
static int
find_ann(asdl_seq *stmts)
{
int i, j, res = 0;
stmt_ty st;
for (i = 0; i < asdl_seq_LEN(stmts); i++) {
st = (stmt_ty)asdl_seq_GET(stmts, i);
switch (st->kind) {
case AnnAssign_kind:
return 1;
case For_kind:
res = find_ann(st->v.For.body) ||
find_ann(st->v.For.orelse);
break;
case AsyncFor_kind:
res = find_ann(st->v.AsyncFor.body) ||
find_ann(st->v.AsyncFor.orelse);
break;
case While_kind:
res = find_ann(st->v.While.body) ||
find_ann(st->v.While.orelse);
break;
case If_kind:
res = find_ann(st->v.If.body) ||
find_ann(st->v.If.orelse);
break;
case With_kind:
res = find_ann(st->v.With.body);
break;
case AsyncWith_kind:
res = find_ann(st->v.AsyncWith.body);
break;
case Try_kind:
for (j = 0; j < asdl_seq_LEN(st->v.Try.handlers); j++) {
excepthandler_ty handler = (excepthandler_ty)asdl_seq_GET(
st->v.Try.handlers, j);
if (find_ann(handler->v.ExceptHandler.body)) {
return 1;
}
}
res = find_ann(st->v.Try.body) ||
find_ann(st->v.Try.finalbody) ||
find_ann(st->v.Try.orelse);
break;
default:
res = 0;
}
if (res) {
break;
}
}
return res;
}
/*
* Frame block handling functions
*/
static int
compiler_push_fblock(struct compiler *c, enum fblocktype t, basicblock *b,
basicblock *exit)
{
struct fblockinfo *f;
if (c->u->u_nfblocks >= CO_MAXBLOCKS) {
PyErr_SetString(PyExc_SyntaxError,
"too many statically nested blocks");
return 0;
}
f = &c->u->u_fblock[c->u->u_nfblocks++];
f->fb_type = t;
f->fb_block = b;
f->fb_exit = exit;
return 1;
}
static void
compiler_pop_fblock(struct compiler *c, enum fblocktype t, basicblock *b)
{
struct compiler_unit *u = c->u;
assert(u->u_nfblocks > 0);
u->u_nfblocks--;
assert(u->u_fblock[u->u_nfblocks].fb_type == t);
assert(u->u_fblock[u->u_nfblocks].fb_block == b);
}
/* Unwind a frame block. If preserve_tos is true, the TOS before
* popping the blocks will be restored afterwards.
*/
static int
compiler_unwind_fblock(struct compiler *c, struct fblockinfo *info,
int preserve_tos)
{
switch (info->fb_type) {
case WHILE_LOOP:
return 1;
case FINALLY_END:
ADDOP_I(c, POP_FINALLY, preserve_tos);
return 1;
case FOR_LOOP:
/* Pop the iterator */
if (preserve_tos) {
ADDOP(c, ROT_TWO);
}
ADDOP(c, POP_TOP);
return 1;
case EXCEPT:
ADDOP(c, POP_BLOCK);
return 1;
case FINALLY_TRY:
ADDOP(c, POP_BLOCK);
ADDOP_JREL(c, CALL_FINALLY, info->fb_exit);
return 1;
case WITH:
case ASYNC_WITH:
ADDOP(c, POP_BLOCK);
if (preserve_tos) {
ADDOP(c, ROT_TWO);
}
ADDOP(c, BEGIN_FINALLY);
ADDOP(c, WITH_CLEANUP_START);
if (info->fb_type == ASYNC_WITH) {
ADDOP(c, GET_AWAITABLE);
ADDOP_LOAD_CONST(c, Py_None);
ADDOP(c, YIELD_FROM);
}
ADDOP(c, WITH_CLEANUP_FINISH);
ADDOP_I(c, POP_FINALLY, 0);
return 1;
case HANDLER_CLEANUP:
if (preserve_tos) {
ADDOP(c, ROT_FOUR);
}
if (info->fb_exit) {
ADDOP(c, POP_BLOCK);
ADDOP(c, POP_EXCEPT);
ADDOP_JREL(c, CALL_FINALLY, info->fb_exit);
}
else {
ADDOP(c, POP_EXCEPT);
}
return 1;
}
Py_UNREACHABLE();
}
/* Compile a sequence of statements, checking for a docstring
and for annotations. */
static int
compiler_body(struct compiler *c, asdl_seq *stmts)
{
int i = 0;
stmt_ty st;
PyObject *docstring;
/* Set current line number to the line number of first statement.
This way line number for SETUP_ANNOTATIONS will always
coincide with the line number of first "real" statement in module.
If body is empy, then lineno will be set later in assemble. */
if (c->u->u_scope_type == COMPILER_SCOPE_MODULE &&
!c->u->u_lineno && asdl_seq_LEN(stmts)) {
st = (stmt_ty)asdl_seq_GET(stmts, 0);
c->u->u_lineno = st->lineno;
}
/* Every annotated class and module should have __annotations__. */
if (find_ann(stmts)) {
ADDOP(c, SETUP_ANNOTATIONS);
}
if (!asdl_seq_LEN(stmts))
return 1;
/* if not -OO mode, set docstring */
if (c->c_optimize < 2) {
docstring = _PyAST_GetDocString(stmts);
if (docstring) {
i = 1;
st = (stmt_ty)asdl_seq_GET(stmts, 0);
assert(st->kind == Expr_kind);
VISIT(c, expr, st->v.Expr.value);
if (!compiler_nameop(c, __doc__, Store))
return 0;
}
}
for (; i < asdl_seq_LEN(stmts); i++)
VISIT(c, stmt, (stmt_ty)asdl_seq_GET(stmts, i));
return 1;
}
static PyCodeObject *
compiler_mod(struct compiler *c, mod_ty mod)
{
PyCodeObject *co;
int addNone = 1;
static PyObject *module;
if (!module) {
module = PyUnicode_InternFromString("<module>");
if (!module)
return NULL;
}
/* Use 0 for firstlineno initially, will fixup in assemble(). */
if (!compiler_enter_scope(c, module, COMPILER_SCOPE_MODULE, mod, 0))
return NULL;
switch (mod->kind) {
case Module_kind:
if (!compiler_body(c, mod->v.Module.body)) {
compiler_exit_scope(c);
return 0;
}
break;
case Interactive_kind:
if (find_ann(mod->v.Interactive.body)) {
ADDOP(c, SETUP_ANNOTATIONS);
}
c->c_interactive = 1;
VISIT_SEQ_IN_SCOPE(c, stmt,
mod->v.Interactive.body);
break;
case Expression_kind:
VISIT_IN_SCOPE(c, expr, mod->v.Expression.body);
addNone = 0;
break;
case Suite_kind:
PyErr_SetString(PyExc_SystemError,
"suite should not be possible");
return 0;
default:
PyErr_Format(PyExc_SystemError,
"module kind %d should not be possible",
mod->kind);
return 0;
}
co = assemble(c, addNone);
compiler_exit_scope(c);
return co;
}
/* The test for LOCAL must come before the test for FREE in order to
handle classes where name is both local and free. The local var is
a method and the free var is a free var referenced within a method.
*/
static int
get_ref_type(struct compiler *c, PyObject *name)
{
int scope;
if (c->u->u_scope_type == COMPILER_SCOPE_CLASS &&
_PyUnicode_EqualToASCIIString(name, "__class__"))
return CELL;
scope = PyST_GetScope(c->u->u_ste, name);
if (scope == 0) {
char buf[350];
PyOS_snprintf(buf, sizeof(buf),
"unknown scope for %.100s in %.100s(%s)\n"
"symbols: %s\nlocals: %s\nglobals: %s",
PyUnicode_AsUTF8(name),
PyUnicode_AsUTF8(c->u->u_name),
PyUnicode_AsUTF8(PyObject_Repr(c->u->u_ste->ste_id)),
PyUnicode_AsUTF8(PyObject_Repr(c->u->u_ste->ste_symbols)),
PyUnicode_AsUTF8(PyObject_Repr(c->u->u_varnames)),
PyUnicode_AsUTF8(PyObject_Repr(c->u->u_names))
);
Py_FatalError(buf);
}
return scope;
}
static int
compiler_lookup_arg(PyObject *dict, PyObject *name)
{
PyObject *v;
v = PyDict_GetItem(dict, name);
if (v == NULL)
return -1;
return PyLong_AS_LONG(v);
}
static int
compiler_make_closure(struct compiler *c, PyCodeObject *co, Py_ssize_t flags, PyObject *qualname)
{
Py_ssize_t i, free = PyCode_GetNumFree(co);
if (qualname == NULL)
qualname = co->co_name;
if (free) {
for (i = 0; i < free; ++i) {
/* Bypass com_addop_varname because it will generate
LOAD_DEREF but LOAD_CLOSURE is needed.
*/
PyObject *name = PyTuple_GET_ITEM(co->co_freevars, i);
int arg, reftype;
/* Special case: If a class contains a method with a
free variable that has the same name as a method,
the name will be considered free *and* local in the
class. It should be handled by the closure, as
well as by the normal name loookup logic.
*/
reftype = get_ref_type(c, name);
if (reftype == CELL)
arg = compiler_lookup_arg(c->u->u_cellvars, name);
else /* (reftype == FREE) */
arg = compiler_lookup_arg(c->u->u_freevars, name);
if (arg == -1) {
fprintf(stderr,
"lookup %s in %s %d %d\n"
"freevars of %s: %s\n",
PyUnicode_AsUTF8(PyObject_Repr(name)),
PyUnicode_AsUTF8(c->u->u_name),
reftype, arg,
PyUnicode_AsUTF8(co->co_name),
PyUnicode_AsUTF8(PyObject_Repr(co->co_freevars)));
Py_FatalError("compiler_make_closure()");
}
ADDOP_I(c, LOAD_CLOSURE, arg);
}
flags |= 0x08;
ADDOP_I(c, BUILD_TUPLE, free);
}
ADDOP_LOAD_CONST(c, (PyObject*)co);
ADDOP_LOAD_CONST(c, qualname);
ADDOP_I(c, MAKE_FUNCTION, flags);
return 1;
}
static int
compiler_decorators(struct compiler *c, asdl_seq* decos)
{
int i;
if (!decos)
return 1;
for (i = 0; i < asdl_seq_LEN(decos); i++) {
VISIT(c, expr, (expr_ty)asdl_seq_GET(decos, i));
}
return 1;
}
static int
compiler_visit_kwonlydefaults(struct compiler *c, asdl_seq *kwonlyargs,
asdl_seq *kw_defaults)
{
/* Push a dict of keyword-only default values.
Return 0 on error, -1 if no dict pushed, 1 if a dict is pushed.
*/
int i;
PyObject *keys = NULL;
for (i = 0; i < asdl_seq_LEN(kwonlyargs); i++) {
arg_ty arg = asdl_seq_GET(kwonlyargs, i);
expr_ty default_ = asdl_seq_GET(kw_defaults, i);
if (default_) {
PyObject *mangled = _Py_Mangle(c->u->u_private, arg->arg);
if (!mangled) {
goto error;
}
if (keys == NULL) {
keys = PyList_New(1);
if (keys == NULL) {
Py_DECREF(mangled);
return 0;
}
PyList_SET_ITEM(keys, 0, mangled);
}
else {
int res = PyList_Append(keys, mangled);
Py_DECREF(mangled);
if (res == -1) {
goto error;
}
}
if (!compiler_visit_expr(c, default_)) {
goto error;
}
}
}
if (keys != NULL) {
Py_ssize_t default_count = PyList_GET_SIZE(keys);
PyObject *keys_tuple = PyList_AsTuple(keys);
Py_DECREF(keys);
ADDOP_LOAD_CONST_NEW(c, keys_tuple);
ADDOP_I(c, BUILD_CONST_KEY_MAP, default_count);
assert(default_count > 0);
return 1;
}
else {
return -1;
}
error:
Py_XDECREF(keys);
return 0;
}
static int
compiler_visit_annexpr(struct compiler *c, expr_ty annotation)
{
ADDOP_LOAD_CONST_NEW(c, _PyAST_ExprAsUnicode(annotation));
return 1;
}
static int
compiler_visit_argannotation(struct compiler *c, identifier id,
expr_ty annotation, PyObject *names)
{
if (annotation) {
PyObject *mangled;
if (c->c_future->ff_features & CO_FUTURE_ANNOTATIONS) {
VISIT(c, annexpr, annotation)
}
else {
VISIT(c, expr, annotation);
}
mangled = _Py_Mangle(c->u->u_private, id);
if (!mangled)
return 0;
if (PyList_Append(names, mangled) < 0) {
Py_DECREF(mangled);
return 0;
}
Py_DECREF(mangled);
}
return 1;
}
static int
compiler_visit_argannotations(struct compiler *c, asdl_seq* args,
PyObject *names)
{
int i;
for (i = 0; i < asdl_seq_LEN(args); i++) {
arg_ty arg = (arg_ty)asdl_seq_GET(args, i);
if (!compiler_visit_argannotation(
c,
arg->arg,
arg->annotation,
names))
return 0;
}
return 1;
}
static int
compiler_visit_annotations(struct compiler *c, arguments_ty args,
expr_ty returns)
{
/* Push arg annotation dict.
The expressions are evaluated out-of-order wrt the source code.
Return 0 on error, -1 if no dict pushed, 1 if a dict is pushed.
*/
static identifier return_str;
PyObject *names;
Py_ssize_t len;
names = PyList_New(0);
if (!names)
return 0;
if (!compiler_visit_argannotations(c, args->args, names))
goto error;
if (args->vararg && args->vararg->annotation &&
!compiler_visit_argannotation(c, args->vararg->arg,
args->vararg->annotation, names))
goto error;
if (!compiler_visit_argannotations(c, args->kwonlyargs, names))
goto error;
if (args->kwarg && args->kwarg->annotation &&
!compiler_visit_argannotation(c, args->kwarg->arg,
args->kwarg->annotation, names))
goto error;
if (!return_str) {
return_str = PyUnicode_InternFromString("return");
if (!return_str)
goto error;
}
if (!compiler_visit_argannotation(c, return_str, returns, names)) {
goto error;
}
len = PyList_GET_SIZE(names);
if (len) {
PyObject *keytuple = PyList_AsTuple(names);
Py_DECREF(names);
ADDOP_LOAD_CONST_NEW(c, keytuple);
ADDOP_I(c, BUILD_CONST_KEY_MAP, len);
return 1;
}
else {
Py_DECREF(names);
return -1;
}
error:
Py_DECREF(names);
return 0;
}
static int
compiler_visit_defaults(struct compiler *c, arguments_ty args)
{
VISIT_SEQ(c, expr, args->defaults);
ADDOP_I(c, BUILD_TUPLE, asdl_seq_LEN(args->defaults));
return 1;
}
static Py_ssize_t
compiler_default_arguments(struct compiler *c, arguments_ty args)
{
Py_ssize_t funcflags = 0;
if (args->defaults && asdl_seq_LEN(args->defaults) > 0) {
if (!compiler_visit_defaults(c, args))
return -1;
funcflags |= 0x01;
}
if (args->kwonlyargs) {
int res = compiler_visit_kwonlydefaults(c, args->kwonlyargs,
args->kw_defaults);
if (res == 0) {
return -1;
}
else if (res > 0) {
funcflags |= 0x02;
}
}
return funcflags;
}
static int
compiler_function(struct compiler *c, stmt_ty s, int is_async)
{
PyCodeObject *co;
PyObject *qualname, *docstring = NULL;
arguments_ty args;
expr_ty returns;
identifier name;
asdl_seq* decos;
asdl_seq *body;
Py_ssize_t i, funcflags;
int annotations;
int scope_type;
if (is_async) {
assert(s->kind == AsyncFunctionDef_kind);
args = s->v.AsyncFunctionDef.args;
returns = s->v.AsyncFunctionDef.returns;
decos = s->v.AsyncFunctionDef.decorator_list;
name = s->v.AsyncFunctionDef.name;
body = s->v.AsyncFunctionDef.body;
scope_type = COMPILER_SCOPE_ASYNC_FUNCTION;
} else {
assert(s->kind == FunctionDef_kind);
args = s->v.FunctionDef.args;
returns = s->v.FunctionDef.returns;
decos = s->v.FunctionDef.decorator_list;
name = s->v.FunctionDef.name;
body = s->v.FunctionDef.body;
scope_type = COMPILER_SCOPE_FUNCTION;
}
if (!compiler_decorators(c, decos))
return 0;
funcflags = compiler_default_arguments(c, args);
if (funcflags == -1) {
return 0;
}
annotations = compiler_visit_annotations(c, args, returns);
if (annotations == 0) {
return 0;
}
else if (annotations > 0) {
funcflags |= 0x04;
}
if (!compiler_enter_scope(c, name, scope_type, (void *)s, s->lineno)) {
return 0;
}
/* if not -OO mode, add docstring */
if (c->c_optimize < 2) {
docstring = _PyAST_GetDocString(body);
}
if (compiler_add_const(c, docstring ? docstring : Py_None) < 0) {
compiler_exit_scope(c);
return 0;
}
c->u->u_argcount = asdl_seq_LEN(args->args);
c->u->u_kwonlyargcount = asdl_seq_LEN(args->kwonlyargs);
VISIT_SEQ_IN_SCOPE(c, stmt, body);
co = assemble(c, 1);
qualname = c->u->u_qualname;
Py_INCREF(qualname);
compiler_exit_scope(c);
if (co == NULL) {
Py_XDECREF(qualname);
Py_XDECREF(co);
return 0;
}
compiler_make_closure(c, co, funcflags, qualname);
Py_DECREF(qualname);
Py_DECREF(co);
/* decorators */
for (i = 0; i < asdl_seq_LEN(decos); i++) {
ADDOP_I(c, CALL_FUNCTION, 1);
}
return compiler_nameop(c, name, Store);
}
static int
compiler_class(struct compiler *c, stmt_ty s)
{
PyCodeObject *co;
PyObject *str;
int i;
asdl_seq* decos = s->v.ClassDef.decorator_list;
if (!compiler_decorators(c, decos))
return 0;
/* ultimately generate code for:
<name> = __build_class__(<func>, <name>, *<bases>, **<keywords>)
where:
<func> is a function/closure created from the class body;
it has a single argument (__locals__) where the dict
(or MutableSequence) representing the locals is passed
<name> is the class name
<bases> is the positional arguments and *varargs argument
<keywords> is the keyword arguments and **kwds argument
This borrows from compiler_call.
*/
/* 1. compile the class body into a code object */
if (!compiler_enter_scope(c, s->v.ClassDef.name,
COMPILER_SCOPE_CLASS, (void *)s, s->lineno))
return 0;
/* this block represents what we do in the new scope */
{
/* use the class name for name mangling */
Py_INCREF(s->v.ClassDef.name);
Py_XSETREF(c->u->u_private, s->v.ClassDef.name);
/* load (global) __name__ ... */
str = PyUnicode_InternFromString("__name__");
if (!str || !compiler_nameop(c, str, Load)) {
Py_XDECREF(str);
compiler_exit_scope(c);
return 0;
}
Py_DECREF(str);
/* ... and store it as __module__ */
str = PyUnicode_InternFromString("__module__");
if (!str || !compiler_nameop(c, str, Store)) {
Py_XDECREF(str);
compiler_exit_scope(c);
return 0;
}
Py_DECREF(str);
assert(c->u->u_qualname);
ADDOP_LOAD_CONST(c, c->u->u_qualname);
str = PyUnicode_InternFromString("__qualname__");
if (!str || !compiler_nameop(c, str, Store)) {
Py_XDECREF(str);
compiler_exit_scope(c);
return 0;
}
Py_DECREF(str);
/* compile the body proper */
if (!compiler_body(c, s->v.ClassDef.body)) {
compiler_exit_scope(c);
return 0;
}
/* Return __classcell__ if it is referenced, otherwise return None */
if (c->u->u_ste->ste_needs_class_closure) {
/* Store __classcell__ into class namespace & return it */
str = PyUnicode_InternFromString("__class__");
if (str == NULL) {
compiler_exit_scope(c);
return 0;
}
i = compiler_lookup_arg(c->u->u_cellvars, str);
Py_DECREF(str);
if (i < 0) {
compiler_exit_scope(c);
return 0;
}
assert(i == 0);
ADDOP_I(c, LOAD_CLOSURE, i);
ADDOP(c, DUP_TOP);
str = PyUnicode_InternFromString("__classcell__");
if (!str || !compiler_nameop(c, str, Store)) {
Py_XDECREF(str);
compiler_exit_scope(c);
return 0;
}
Py_DECREF(str);
}
else {
/* No methods referenced __class__, so just return None */
assert(PyDict_GET_SIZE(c->u->u_cellvars) == 0);
ADDOP_LOAD_CONST(c, Py_None);
}
ADDOP_IN_SCOPE(c, RETURN_VALUE);
/* create the code object */
co = assemble(c, 1);
}
/* leave the new scope */
compiler_exit_scope(c);
if (co == NULL)
return 0;
/* 2. load the 'build_class' function */
ADDOP(c, LOAD_BUILD_CLASS);
/* 3. load a function (or closure) made from the code object */
compiler_make_closure(c, co, 0, NULL);
Py_DECREF(co);
/* 4. load class name */
ADDOP_LOAD_CONST(c, s->v.ClassDef.name);
/* 5. generate the rest of the code for the call */
if (!compiler_call_helper(c, 2,
s->v.ClassDef.bases,
s->v.ClassDef.keywords))
return 0;
/* 6. apply decorators */
for (i = 0; i < asdl_seq_LEN(decos); i++) {
ADDOP_I(c, CALL_FUNCTION, 1);
}
/* 7. store into <name> */
if (!compiler_nameop(c, s->v.ClassDef.name, Store))
return 0;
return 1;
}
static int
cmpop(cmpop_ty op)
{
switch (op) {
case Eq:
return PyCmp_EQ;
case NotEq:
return PyCmp_NE;
case Lt:
return PyCmp_LT;
case LtE:
return PyCmp_LE;
case Gt:
return PyCmp_GT;
case GtE:
return PyCmp_GE;
case Is:
return PyCmp_IS;
case IsNot:
return PyCmp_IS_NOT;
case In:
return PyCmp_IN;
case NotIn:
return PyCmp_NOT_IN;
default:
return PyCmp_BAD;
}
}
static int
compiler_jump_if(struct compiler *c, expr_ty e, basicblock *next, int cond)
{
switch (e->kind) {
case UnaryOp_kind:
if (e->v.UnaryOp.op == Not)
return compiler_jump_if(c, e->v.UnaryOp.operand, next, !cond);
/* fallback to general implementation */
break;
case BoolOp_kind: {
asdl_seq *s = e->v.BoolOp.values;
Py_ssize_t i, n = asdl_seq_LEN(s) - 1;
assert(n >= 0);
int cond2 = e->v.BoolOp.op == Or;
basicblock *next2 = next;
if (!cond2 != !cond) {
next2 = compiler_new_block(c);
if (next2 == NULL)
return 0;
}
for (i = 0; i < n; ++i) {
if (!compiler_jump_if(c, (expr_ty)asdl_seq_GET(s, i), next2, cond2))
return 0;
}
if (!compiler_jump_if(c, (expr_ty)asdl_seq_GET(s, n), next, cond))
return 0;
if (next2 != next)
compiler_use_next_block(c, next2);
return 1;
}
case IfExp_kind: {
basicblock *end, *next2;
end = compiler_new_block(c);
if (end == NULL)
return 0;
next2 = compiler_new_block(c);
if (next2 == NULL)
return 0;
if (!compiler_jump_if(c, e->v.IfExp.test, next2, 0))
return 0;
if (!compiler_jump_if(c, e->v.IfExp.body, next, cond))
return 0;
ADDOP_JREL(c, JUMP_FORWARD, end);
compiler_use_next_block(c, next2);
if (!compiler_jump_if(c, e->v.IfExp.orelse, next, cond))
return 0;
compiler_use_next_block(c, end);
return 1;
}
case Compare_kind: {
Py_ssize_t i, n = asdl_seq_LEN(e->v.Compare.ops) - 1;
if (n > 0) {
basicblock *cleanup = compiler_new_block(c);
if (cleanup == NULL)
return 0;
VISIT(c, expr, e->v.Compare.left);
for (i = 0; i < n; i++) {
VISIT(c, expr,
(expr_ty)asdl_seq_GET(e->v.Compare.comparators, i));
ADDOP(c, DUP_TOP);
ADDOP(c, ROT_THREE);
ADDOP_I(c, COMPARE_OP,
cmpop((cmpop_ty)(asdl_seq_GET(e->v.Compare.ops, i))));
ADDOP_JABS(c, POP_JUMP_IF_FALSE, cleanup);
NEXT_BLOCK(c);
}
VISIT(c, expr, (expr_ty)asdl_seq_GET(e->v.Compare.comparators, n));
ADDOP_I(c, COMPARE_OP,
cmpop((cmpop_ty)(asdl_seq_GET(e->v.Compare.ops, n))));
ADDOP_JABS(c, cond ? POP_JUMP_IF_TRUE : POP_JUMP_IF_FALSE, next);
basicblock *end = compiler_new_block(c);
if (end == NULL)
return 0;
ADDOP_JREL(c, JUMP_FORWARD, end);
compiler_use_next_block(c, cleanup);
ADDOP(c, POP_TOP);
if (!cond) {
ADDOP_JREL(c, JUMP_FORWARD, next);
}
compiler_use_next_block(c, end);
return 1;
}
/* fallback to general implementation */
break;
}
default:
/* fallback to general implementation */
break;
}
/* general implementation */
VISIT(c, expr, e);
ADDOP_JABS(c, cond ? POP_JUMP_IF_TRUE : POP_JUMP_IF_FALSE, next);
return 1;
}
static int
compiler_ifexp(struct compiler *c, expr_ty e)
{
basicblock *end, *next;
assert(e->kind == IfExp_kind);
end = compiler_new_block(c);
if (end == NULL)
return 0;
next = compiler_new_block(c);
if (next == NULL)
return 0;
if (!compiler_jump_if(c, e->v.IfExp.test, next, 0))
return 0;
VISIT(c, expr, e->v.IfExp.body);
ADDOP_JREL(c, JUMP_FORWARD, end);
compiler_use_next_block(c, next);
VISIT(c, expr, e->v.IfExp.orelse);
compiler_use_next_block(c, end);
return 1;
}
static int
compiler_lambda(struct compiler *c, expr_ty e)
{
PyCodeObject *co;
PyObject *qualname;
static identifier name;
Py_ssize_t funcflags;
arguments_ty args = e->v.Lambda.args;
assert(e->kind == Lambda_kind);
if (!name) {
name = PyUnicode_InternFromString("<lambda>");
if (!name)
return 0;
}
funcflags = compiler_default_arguments(c, args);
if (funcflags == -1) {
return 0;
}
if (!compiler_enter_scope(c, name, COMPILER_SCOPE_LAMBDA,
(void *)e, e->lineno))
return 0;
/* Make None the first constant, so the lambda can't have a
docstring. */
if (compiler_add_const(c, Py_None) < 0)
return 0;
c->u->u_argcount = asdl_seq_LEN(args->args);
c->u->u_kwonlyargcount = asdl_seq_LEN(args->kwonlyargs);
VISIT_IN_SCOPE(c, expr, e->v.Lambda.body);
if (c->u->u_ste->ste_generator) {
co = assemble(c, 0);
}
else {
ADDOP_IN_SCOPE(c, RETURN_VALUE);
co = assemble(c, 1);
}
qualname = c->u->u_qualname;
Py_INCREF(qualname);
compiler_exit_scope(c);
if (co == NULL)
return 0;
compiler_make_closure(c, co, funcflags, qualname);
Py_DECREF(qualname);
Py_DECREF(co);
return 1;
}
static int
compiler_if(struct compiler *c, stmt_ty s)
{
basicblock *end, *next;
int constant;
assert(s->kind == If_kind);
end = compiler_new_block(c);
if (end == NULL)
return 0;
constant = expr_constant(s->v.If.test);
/* constant = 0: "if 0"
* constant = 1: "if 1", "if 2", ...
* constant = -1: rest */
if (constant == 0) {
if (s->v.If.orelse)
VISIT_SEQ(c, stmt, s->v.If.orelse);
} else if (constant == 1) {
VISIT_SEQ(c, stmt, s->v.If.body);
} else {
if (asdl_seq_LEN(s->v.If.orelse)) {
next = compiler_new_block(c);
if (next == NULL)
return 0;
}
else
next = end;
if (!compiler_jump_if(c, s->v.If.test, next, 0))
return 0;
VISIT_SEQ(c, stmt, s->v.If.body);
if (asdl_seq_LEN(s->v.If.orelse)) {
ADDOP_JREL(c, JUMP_FORWARD, end);
compiler_use_next_block(c, next);
VISIT_SEQ(c, stmt, s->v.If.orelse);
}
}
compiler_use_next_block(c, end);
return 1;
}
static int
compiler_for(struct compiler *c, stmt_ty s)
{
basicblock *start, *cleanup, *end;
start = compiler_new_block(c);
cleanup = compiler_new_block(c);
end = compiler_new_block(c);
if (start == NULL || end == NULL || cleanup == NULL)
return 0;
if (!compiler_push_fblock(c, FOR_LOOP, start, end))
return 0;
VISIT(c, expr, s->v.For.iter);
ADDOP(c, GET_ITER);
compiler_use_next_block(c, start);
ADDOP_JREL(c, FOR_ITER, cleanup);
VISIT(c, expr, s->v.For.target);
VISIT_SEQ(c, stmt, s->v.For.body);
ADDOP_JABS(c, JUMP_ABSOLUTE, start);
compiler_use_next_block(c, cleanup);
compiler_pop_fblock(c, FOR_LOOP, start);
VISIT_SEQ(c, stmt, s->v.For.orelse);
compiler_use_next_block(c, end);
return 1;
}
static int
compiler_async_for(struct compiler *c, stmt_ty s)
{
basicblock *start, *except, *end;
if (c->u->u_scope_type != COMPILER_SCOPE_ASYNC_FUNCTION) {
return compiler_error(c, "'async for' outside async function");
}
start = compiler_new_block(c);
except = compiler_new_block(c);
end = compiler_new_block(c);
if (start == NULL || except == NULL || end == NULL)
return 0;
VISIT(c, expr, s->v.AsyncFor.iter);
ADDOP(c, GET_AITER);
compiler_use_next_block(c, start);
if (!compiler_push_fblock(c, FOR_LOOP, start, end))
return 0;
/* SETUP_FINALLY to guard the __anext__ call */
ADDOP_JREL(c, SETUP_FINALLY, except);
ADDOP(c, GET_ANEXT);
ADDOP_LOAD_CONST(c, Py_None);
ADDOP(c, YIELD_FROM);
ADDOP(c, POP_BLOCK); /* for SETUP_FINALLY */
/* Success block for __anext__ */
VISIT(c, expr, s->v.AsyncFor.target);
VISIT_SEQ(c, stmt, s->v.AsyncFor.body);
ADDOP_JABS(c, JUMP_ABSOLUTE, start);
compiler_pop_fblock(c, FOR_LOOP, start);
/* Except block for __anext__ */
compiler_use_next_block(c, except);
ADDOP(c, END_ASYNC_FOR);
/* `else` block */
VISIT_SEQ(c, stmt, s->v.For.orelse);
compiler_use_next_block(c, end);
return 1;
}
static int
compiler_while(struct compiler *c, stmt_ty s)
{
basicblock *loop, *orelse, *end, *anchor = NULL;
int constant = expr_constant(s->v.While.test);
if (constant == 0) {
if (s->v.While.orelse)
VISIT_SEQ(c, stmt, s->v.While.orelse);
return 1;
}
loop = compiler_new_block(c);
end = compiler_new_block(c);
if (constant == -1) {
anchor = compiler_new_block(c);
if (anchor == NULL)
return 0;
}
if (loop == NULL || end == NULL)
return 0;
if (s->v.While.orelse) {
orelse = compiler_new_block(c);
if (orelse == NULL)
return 0;
}
else
orelse = NULL;
compiler_use_next_block(c, loop);
if (!compiler_push_fblock(c, WHILE_LOOP, loop, end))
return 0;
if (constant == -1) {
if (!compiler_jump_if(c, s->v.While.test, anchor, 0))
return 0;
}
VISIT_SEQ(c, stmt, s->v.While.body);
ADDOP_JABS(c, JUMP_ABSOLUTE, loop);
/* XXX should the two POP instructions be in a separate block
if there is no else clause ?
*/
if (constant == -1)
compiler_use_next_block(c, anchor);
compiler_pop_fblock(c, WHILE_LOOP, loop);
if (orelse != NULL) /* what if orelse is just pass? */
VISIT_SEQ(c, stmt, s->v.While.orelse);
compiler_use_next_block(c, end);
return 1;
}
static int
compiler_return(struct compiler *c, stmt_ty s)
{
int preserve_tos = ((s->v.Return.value != NULL) &&
!is_const(s->v.Return.value));
if (c->u->u_ste->ste_type != FunctionBlock)
return compiler_error(c, "'return' outside function");
if (s->v.Return.value != NULL &&
c->u->u_ste->ste_coroutine && c->u->u_ste->ste_generator)
{
return compiler_error(
c, "'return' with value in async generator");
}
if (preserve_tos) {
VISIT(c, expr, s->v.Return.value);
}
for (int depth = c->u->u_nfblocks; depth--;) {
struct fblockinfo *info = &c->u->u_fblock[depth];
if (!compiler_unwind_fblock(c, info, preserve_tos))
return 0;
}
if (s->v.Return.value == NULL) {
ADDOP_LOAD_CONST(c, Py_None);
}
else if (!preserve_tos) {
VISIT(c, expr, s->v.Return.value);
}
ADDOP(c, RETURN_VALUE);
return 1;
}
static int
compiler_break(struct compiler *c)
{
for (int depth = c->u->u_nfblocks; depth--;) {
struct fblockinfo *info = &c->u->u_fblock[depth];
if (!compiler_unwind_fblock(c, info, 0))
return 0;
if (info->fb_type == WHILE_LOOP || info->fb_type == FOR_LOOP) {
ADDOP_JABS(c, JUMP_ABSOLUTE, info->fb_exit);
return 1;
}
}
return compiler_error(c, "'break' outside loop");
}
static int
compiler_continue(struct compiler *c)
{
for (int depth = c->u->u_nfblocks; depth--;) {
struct fblockinfo *info = &c->u->u_fblock[depth];
if (info->fb_type == WHILE_LOOP || info->fb_type == FOR_LOOP) {
ADDOP_JABS(c, JUMP_ABSOLUTE, info->fb_block);
return 1;
}
if (!compiler_unwind_fblock(c, info, 0))
return 0;
}
return compiler_error(c, "'continue' not properly in loop");
}
/* Code generated for "try: <body> finally: <finalbody>" is as follows:
SETUP_FINALLY L
<code for body>
POP_BLOCK
BEGIN_FINALLY
L:
<code for finalbody>
END_FINALLY
The special instructions use the block stack. Each block
stack entry contains the instruction that created it (here
SETUP_FINALLY), the level of the value stack at the time the
block stack entry was created, and a label (here L).
SETUP_FINALLY:
Pushes the current value stack level and the label
onto the block stack.
POP_BLOCK:
Pops en entry from the block stack.
BEGIN_FINALLY
Pushes NULL onto the value stack.
END_FINALLY:
Pops 1 (NULL or int) or 6 entries from the *value* stack and restore
the raised and the caught exceptions they specify.
The block stack is unwound when an exception is raised:
when a SETUP_FINALLY entry is found, the raised and the caught
exceptions are pushed onto the value stack (and the exception
condition is cleared), and the interpreter jumps to the label
gotten from the block stack.
*/
static int
compiler_try_finally(struct compiler *c, stmt_ty s)
{
basicblock *body, *end;
body = compiler_new_block(c);
end = compiler_new_block(c);
if (body == NULL || end == NULL)
return 0;
/* `try` block */
ADDOP_JREL(c, SETUP_FINALLY, end);
compiler_use_next_block(c, body);
if (!compiler_push_fblock(c, FINALLY_TRY, body, end))
return 0;
if (s->v.Try.handlers && asdl_seq_LEN(s->v.Try.handlers)) {
if (!compiler_try_except(c, s))
return 0;
}
else {
VISIT_SEQ(c, stmt, s->v.Try.body);
}
ADDOP(c, POP_BLOCK);
ADDOP(c, BEGIN_FINALLY);
compiler_pop_fblock(c, FINALLY_TRY, body);
/* `finally` block */
compiler_use_next_block(c, end);
if (!compiler_push_fblock(c, FINALLY_END, end, NULL))
return 0;
VISIT_SEQ(c, stmt, s->v.Try.finalbody);
ADDOP(c, END_FINALLY);
compiler_pop_fblock(c, FINALLY_END, end);
return 1;
}
/*
Code generated for "try: S except E1 as V1: S1 except E2 as V2: S2 ...":
(The contents of the value stack is shown in [], with the top
at the right; 'tb' is trace-back info, 'val' the exception's
associated value, and 'exc' the exception.)
Value stack Label Instruction Argument
[] SETUP_FINALLY L1
[] <code for S>
[] POP_BLOCK
[] JUMP_FORWARD L0
[tb, val, exc] L1: DUP )
[tb, val, exc, exc] <evaluate E1> )
[tb, val, exc, exc, E1] COMPARE_OP EXC_MATCH ) only if E1
[tb, val, exc, 1-or-0] POP_JUMP_IF_FALSE L2 )
[tb, val, exc] POP
[tb, val] <assign to V1> (or POP if no V1)
[tb] POP
[] <code for S1>
JUMP_FORWARD L0
[tb, val, exc] L2: DUP
.............................etc.......................
[tb, val, exc] Ln+1: END_FINALLY # re-raise exception
[] L0: <next statement>
Of course, parts are not generated if Vi or Ei is not present.
*/
static int
compiler_try_except(struct compiler *c, stmt_ty s)
{
basicblock *body, *orelse, *except, *end;
Py_ssize_t i, n;
body = compiler_new_block(c);
except = compiler_new_block(c);
orelse = compiler_new_block(c);
end = compiler_new_block(c);
if (body == NULL || except == NULL || orelse == NULL || end == NULL)
return 0;
ADDOP_JREL(c, SETUP_FINALLY, except);
compiler_use_next_block(c, body);
if (!compiler_push_fblock(c, EXCEPT, body, NULL))
return 0;
VISIT_SEQ(c, stmt, s->v.Try.body);
ADDOP(c, POP_BLOCK);
compiler_pop_fblock(c, EXCEPT, body);
ADDOP_JREL(c, JUMP_FORWARD, orelse);
n = asdl_seq_LEN(s->v.Try.handlers);
compiler_use_next_block(c, except);
for (i = 0; i < n; i++) {
excepthandler_ty handler = (excepthandler_ty)asdl_seq_GET(
s->v.Try.handlers, i);
if (!handler->v.ExceptHandler.type && i < n-1)
return compiler_error(c, "default 'except:' must be last");
c->u->u_lineno_set = 0;
c->u->u_lineno = handler->lineno;
c->u->u_col_offset = handler->col_offset;
except = compiler_new_block(c);
if (except == NULL)
return 0;
if (handler->v.ExceptHandler.type) {
ADDOP(c, DUP_TOP);
VISIT(c, expr, handler->v.ExceptHandler.type);
ADDOP_I(c, COMPARE_OP, PyCmp_EXC_MATCH);
ADDOP_JABS(c, POP_JUMP_IF_FALSE, except);
}
ADDOP(c, POP_TOP);
if (handler->v.ExceptHandler.name) {
basicblock *cleanup_end, *cleanup_body;
cleanup_end = compiler_new_block(c);
cleanup_body = compiler_new_block(c);
if (!(cleanup_end || cleanup_body))
return 0;
compiler_nameop(c, handler->v.ExceptHandler.name, Store);
ADDOP(c, POP_TOP);
/*
try:
# body
except type as name:
try:
# body
finally:
name = None
del name
*/
/* second try: */
ADDOP_JREL(c, SETUP_FINALLY, cleanup_end);
compiler_use_next_block(c, cleanup_body);
if (!compiler_push_fblock(c, HANDLER_CLEANUP, cleanup_body, cleanup_end))
return 0;
/* second # body */
VISIT_SEQ(c, stmt, handler->v.ExceptHandler.body);
ADDOP(c, POP_BLOCK);
ADDOP(c, BEGIN_FINALLY);
compiler_pop_fblock(c, HANDLER_CLEANUP, cleanup_body);
/* finally: */
compiler_use_next_block(c, cleanup_end);
if (!compiler_push_fblock(c, FINALLY_END, cleanup_end, NULL))
return 0;
/* name = None; del name */
ADDOP_LOAD_CONST(c, Py_None);
compiler_nameop(c, handler->v.ExceptHandler.name, Store);
compiler_nameop(c, handler->v.ExceptHandler.name, Del);
ADDOP(c, END_FINALLY);
ADDOP(c, POP_EXCEPT);
compiler_pop_fblock(c, FINALLY_END, cleanup_end);
}
else {
basicblock *cleanup_body;
cleanup_body = compiler_new_block(c);
if (!cleanup_body)
return 0;
ADDOP(c, POP_TOP);
ADDOP(c, POP_TOP);
compiler_use_next_block(c, cleanup_body);
if (!compiler_push_fblock(c, HANDLER_CLEANUP, cleanup_body, NULL))
return 0;
VISIT_SEQ(c, stmt, handler->v.ExceptHandler.body);
ADDOP(c, POP_EXCEPT);
compiler_pop_fblock(c, HANDLER_CLEANUP, cleanup_body);
}
ADDOP_JREL(c, JUMP_FORWARD, end);
compiler_use_next_block(c, except);
}
ADDOP(c, END_FINALLY);
compiler_use_next_block(c, orelse);
VISIT_SEQ(c, stmt, s->v.Try.orelse);
compiler_use_next_block(c, end);
return 1;
}
static int
compiler_try(struct compiler *c, stmt_ty s) {
if (s->v.Try.finalbody && asdl_seq_LEN(s->v.Try.finalbody))
return compiler_try_finally(c, s);
else
return compiler_try_except(c, s);
}
static int
compiler_import_as(struct compiler *c, identifier name, identifier asname)
{
/* The IMPORT_NAME opcode was already generated. This function
merely needs to bind the result to a name.
If there is a dot in name, we need to split it and emit a
IMPORT_FROM for each name.
*/
Py_ssize_t len = PyUnicode_GET_LENGTH(name);
Py_ssize_t dot = PyUnicode_FindChar(name, '.', 0, len, 1);
if (dot == -2)
return 0;
if (dot != -1) {
/* Consume the base module name to get the first attribute */
while (1) {
Py_ssize_t pos = dot + 1;
PyObject *attr;
dot = PyUnicode_FindChar(name, '.', pos, len, 1);
if (dot == -2)
return 0;
attr = PyUnicode_Substring(name, pos, (dot != -1) ? dot : len);
if (!attr)
return 0;
ADDOP_N(c, IMPORT_FROM, attr, names);
if (dot == -1) {
break;
}
ADDOP(c, ROT_TWO);
ADDOP(c, POP_TOP);
}
if (!compiler_nameop(c, asname, Store)) {
return 0;
}
ADDOP(c, POP_TOP);
return 1;
}
return compiler_nameop(c, asname, Store);
}
static int
compiler_import(struct compiler *c, stmt_ty s)
{
/* The Import node stores a module name like a.b.c as a single
string. This is convenient for all cases except
import a.b.c as d
where we need to parse that string to extract the individual
module names.
XXX Perhaps change the representation to make this case simpler?
*/
Py_ssize_t i, n = asdl_seq_LEN(s->v.Import.names);
for (i = 0; i < n; i++) {
alias_ty alias = (alias_ty)asdl_seq_GET(s->v.Import.names, i);
int r;
ADDOP_LOAD_CONST(c, _PyLong_Zero);
ADDOP_LOAD_CONST(c, Py_None);
ADDOP_NAME(c, IMPORT_NAME, alias->name, names);
if (alias->asname) {
r = compiler_import_as(c, alias->name, alias->asname);
if (!r)
return r;
}
else {
identifier tmp = alias->name;
Py_ssize_t dot = PyUnicode_FindChar(
alias->name, '.', 0, PyUnicode_GET_LENGTH(alias->name), 1);
if (dot != -1) {
tmp = PyUnicode_Substring(alias->name, 0, dot);
if (tmp == NULL)
return 0;
}
r = compiler_nameop(c, tmp, Store);
if (dot != -1) {
Py_DECREF(tmp);
}
if (!r)
return r;
}
}
return 1;
}
static int
compiler_from_import(struct compiler *c, stmt_ty s)
{
Py_ssize_t i, n = asdl_seq_LEN(s->v.ImportFrom.names);
PyObject *names;
static PyObject *empty_string;
if (!empty_string) {
empty_string = PyUnicode_FromString("");
if (!empty_string)
return 0;
}
ADDOP_LOAD_CONST_NEW(c, PyLong_FromLong(s->v.ImportFrom.level));
names = PyTuple_New(n);
if (!names)
return 0;
/* build up the names */
for (i = 0; i < n; i++) {
alias_ty alias = (alias_ty)asdl_seq_GET(s->v.ImportFrom.names, i);
Py_INCREF(alias->name);
PyTuple_SET_ITEM(names, i, alias->name);
}
if (s->lineno > c->c_future->ff_lineno && s->v.ImportFrom.module &&
_PyUnicode_EqualToASCIIString(s->v.ImportFrom.module, "__future__")) {
Py_DECREF(names);
return compiler_error(c, "from __future__ imports must occur "
"at the beginning of the file");
}
ADDOP_LOAD_CONST_NEW(c, names);
if (s->v.ImportFrom.module) {
ADDOP_NAME(c, IMPORT_NAME, s->v.ImportFrom.module, names);
}
else {
ADDOP_NAME(c, IMPORT_NAME, empty_string, names);
}
for (i = 0; i < n; i++) {
alias_ty alias = (alias_ty)asdl_seq_GET(s->v.ImportFrom.names, i);
identifier store_name;
if (i == 0 && PyUnicode_READ_CHAR(alias->name, 0) == '*') {
assert(n == 1);
ADDOP(c, IMPORT_STAR);
return 1;
}
ADDOP_NAME(c, IMPORT_FROM, alias->name, names);
store_name = alias->name;
if (alias->asname)
store_name = alias->asname;
if (!compiler_nameop(c, store_name, Store)) {
return 0;
}
}
/* remove imported module */
ADDOP(c, POP_TOP);
return 1;
}
static int
compiler_assert(struct compiler *c, stmt_ty s)
{
static PyObject *assertion_error = NULL;
basicblock *end;
PyObject* msg;
if (c->c_optimize)
return 1;
if (assertion_error == NULL) {
assertion_error = PyUnicode_InternFromString("AssertionError");
if (assertion_error == NULL)
return 0;
}
if (s->v.Assert.test->kind == Tuple_kind &&
asdl_seq_LEN(s->v.Assert.test->v.Tuple.elts) > 0) {
msg = PyUnicode_FromString("assertion is always true, "
"perhaps remove parentheses?");
if (msg == NULL)
return 0;
if (PyErr_WarnExplicitObject(PyExc_SyntaxWarning, msg,
c->c_filename, c->u->u_lineno,
NULL, NULL) == -1) {
Py_DECREF(msg);
return 0;
}
Py_DECREF(msg);
}
end = compiler_new_block(c);
if (end == NULL)
return 0;
if (!compiler_jump_if(c, s->v.Assert.test, end, 1))
return 0;
ADDOP_O(c, LOAD_GLOBAL, assertion_error, names);
if (s->v.Assert.msg) {
VISIT(c, expr, s->v.Assert.msg);
ADDOP_I(c, CALL_FUNCTION, 1);
}
ADDOP_I(c, RAISE_VARARGS, 1);
compiler_use_next_block(c, end);
return 1;
}
static int
compiler_visit_stmt_expr(struct compiler *c, expr_ty value)
{
if (c->c_interactive && c->c_nestlevel <= 1) {
VISIT(c, expr, value);
ADDOP(c, PRINT_EXPR);
return 1;
}
if (is_const(value)) {
/* ignore constant statement */
return 1;
}
VISIT(c, expr, value);
ADDOP(c, POP_TOP);
return 1;
}
static int
compiler_visit_stmt(struct compiler *c, stmt_ty s)
{
Py_ssize_t i, n;
/* Always assign a lineno to the next instruction for a stmt. */
c->u->u_lineno = s->lineno;
c->u->u_col_offset = s->col_offset;
c->u->u_lineno_set = 0;
switch (s->kind) {
case FunctionDef_kind:
return compiler_function(c, s, 0);
case ClassDef_kind:
return compiler_class(c, s);
case Return_kind:
return compiler_return(c, s);
case Delete_kind:
VISIT_SEQ(c, expr, s->v.Delete.targets)
break;
case Assign_kind:
n = asdl_seq_LEN(s->v.Assign.targets);
VISIT(c, expr, s->v.Assign.value);
for (i = 0; i < n; i++) {
if (i < n - 1)
ADDOP(c, DUP_TOP);
VISIT(c, expr,
(expr_ty)asdl_seq_GET(s->v.Assign.targets, i));
}
break;
case AugAssign_kind:
return compiler_augassign(c, s);
case AnnAssign_kind:
return compiler_annassign(c, s);
case For_kind:
return compiler_for(c, s);
case While_kind:
return compiler_while(c, s);
case If_kind:
return compiler_if(c, s);
case Raise_kind:
n = 0;
if (s->v.Raise.exc) {
VISIT(c, expr, s->v.Raise.exc);
n++;
if (s->v.Raise.cause) {
VISIT(c, expr, s->v.Raise.cause);
n++;
}
}
ADDOP_I(c, RAISE_VARARGS, (int)n);
break;
case Try_kind:
return compiler_try(c, s);
case Assert_kind:
return compiler_assert(c, s);
case Import_kind:
return compiler_import(c, s);
case ImportFrom_kind:
return compiler_from_import(c, s);
case Global_kind:
case Nonlocal_kind:
break;
case Expr_kind:
return compiler_visit_stmt_expr(c, s->v.Expr.value);
case Pass_kind:
break;
case Break_kind:
return compiler_break(c);
case Continue_kind:
return compiler_continue(c);
case With_kind:
return compiler_with(c, s, 0);
case AsyncFunctionDef_kind:
return compiler_function(c, s, 1);
case AsyncWith_kind:
return compiler_async_with(c, s, 0);
case AsyncFor_kind:
return compiler_async_for(c, s);
}
return 1;
}
static int
unaryop(unaryop_ty op)
{
switch (op) {
case Invert:
return UNARY_INVERT;
case Not:
return UNARY_NOT;
case UAdd:
return UNARY_POSITIVE;
case USub:
return UNARY_NEGATIVE;
default:
PyErr_Format(PyExc_SystemError,
"unary op %d should not be possible", op);
return 0;
}
}
static int
binop(struct compiler *c, operator_ty op)
{
switch (op) {
case Add:
return BINARY_ADD;
case Sub:
return BINARY_SUBTRACT;
case Mult:
return BINARY_MULTIPLY;
case MatMult:
return BINARY_MATRIX_MULTIPLY;
case Div:
return BINARY_TRUE_DIVIDE;
case Mod:
return BINARY_MODULO;
case Pow:
return BINARY_POWER;
case LShift:
return BINARY_LSHIFT;
case RShift:
return BINARY_RSHIFT;
case BitOr:
return BINARY_OR;
case BitXor:
return BINARY_XOR;
case BitAnd:
return BINARY_AND;
case FloorDiv:
return BINARY_FLOOR_DIVIDE;
default:
PyErr_Format(PyExc_SystemError,
"binary op %d should not be possible", op);
return 0;
}
}
static int
inplace_binop(struct compiler *c, operator_ty op)
{
switch (op) {
case Add:
return INPLACE_ADD;
case Sub:
return INPLACE_SUBTRACT;
case Mult:
return INPLACE_MULTIPLY;
case MatMult:
return INPLACE_MATRIX_MULTIPLY;
case Div:
return INPLACE_TRUE_DIVIDE;
case Mod:
return INPLACE_MODULO;
case Pow:
return INPLACE_POWER;
case LShift:
return INPLACE_LSHIFT;
case RShift:
return INPLACE_RSHIFT;
case BitOr:
return INPLACE_OR;
case BitXor:
return INPLACE_XOR;
case BitAnd:
return INPLACE_AND;
case FloorDiv:
return INPLACE_FLOOR_DIVIDE;
default:
PyErr_Format(PyExc_SystemError,
"inplace binary op %d should not be possible", op);
return 0;
}
}
static int
compiler_nameop(struct compiler *c, identifier name, expr_context_ty ctx)
{
int op, scope;
Py_ssize_t arg;
enum { OP_FAST, OP_GLOBAL, OP_DEREF, OP_NAME } optype;
PyObject *dict = c->u->u_names;
PyObject *mangled;
/* XXX AugStore isn't used anywhere! */
assert(!_PyUnicode_EqualToASCIIString(name, "None") &&
!_PyUnicode_EqualToASCIIString(name, "True") &&
!_PyUnicode_EqualToASCIIString(name, "False"));
mangled = _Py_Mangle(c->u->u_private, name);
if (!mangled)
return 0;
op = 0;
optype = OP_NAME;
scope = PyST_GetScope(c->u->u_ste, mangled);
switch (scope) {
case FREE:
dict = c->u->u_freevars;
optype = OP_DEREF;
break;
case CELL:
dict = c->u->u_cellvars;
optype = OP_DEREF;
break;
case LOCAL:
if (c->u->u_ste->ste_type == FunctionBlock)
optype = OP_FAST;
break;
case GLOBAL_IMPLICIT:
if (c->u->u_ste->ste_type == FunctionBlock)
optype = OP_GLOBAL;
break;
case GLOBAL_EXPLICIT:
optype = OP_GLOBAL;
break;
default:
/* scope can be 0 */
break;
}
/* XXX Leave assert here, but handle __doc__ and the like better */
assert(scope || PyUnicode_READ_CHAR(name, 0) == '_');
switch (optype) {
case OP_DEREF:
switch (ctx) {
case Load:
op = (c->u->u_ste->ste_type == ClassBlock) ? LOAD_CLASSDEREF : LOAD_DEREF;
break;
case Store: op = STORE_DEREF; break;
case AugLoad:
case AugStore:
break;
case Del: op = DELETE_DEREF; break;
case Param:
default:
PyErr_SetString(PyExc_SystemError,
"param invalid for deref variable");
return 0;
}
break;
case OP_FAST:
switch (ctx) {
case Load: op = LOAD_FAST; break;
case Store: op = STORE_FAST; break;
case Del: op = DELETE_FAST; break;
case AugLoad:
case AugStore:
break;
case Param:
default:
PyErr_SetString(PyExc_SystemError,
"param invalid for local variable");
return 0;
}
ADDOP_N(c, op, mangled, varnames);
return 1;
case OP_GLOBAL:
switch (ctx) {
case Load: op = LOAD_GLOBAL; break;
case Store: op = STORE_GLOBAL; break;
case Del: op = DELETE_GLOBAL; break;
case AugLoad:
case AugStore:
break;
case Param:
default:
PyErr_SetString(PyExc_SystemError,
"param invalid for global variable");
return 0;
}
break;
case OP_NAME:
switch (ctx) {
case Load: op = LOAD_NAME; break;
case Store: op = STORE_NAME; break;
case Del: op = DELETE_NAME; break;
case AugLoad:
case AugStore:
break;
case Param:
default:
PyErr_SetString(PyExc_SystemError,
"param invalid for name variable");
return 0;
}
break;
}
assert(op);
arg = compiler_add_o(c, dict, mangled);
Py_DECREF(mangled);
if (arg < 0)
return 0;
return compiler_addop_i(c, op, arg);
}
static int
compiler_boolop(struct compiler *c, expr_ty e)
{
basicblock *end;
int jumpi;
Py_ssize_t i, n;
asdl_seq *s;
assert(e->kind == BoolOp_kind);
if (e->v.BoolOp.op == And)
jumpi = JUMP_IF_FALSE_OR_POP;
else
jumpi = JUMP_IF_TRUE_OR_POP;
end = compiler_new_block(c);
if (end == NULL)
return 0;
s = e->v.BoolOp.values;
n = asdl_seq_LEN(s) - 1;
assert(n >= 0);
for (i = 0; i < n; ++i) {
VISIT(c, expr, (expr_ty)asdl_seq_GET(s, i));
ADDOP_JABS(c, jumpi, end);
}
VISIT(c, expr, (expr_ty)asdl_seq_GET(s, n));
compiler_use_next_block(c, end);
return 1;
}
static int
starunpack_helper(struct compiler *c, asdl_seq *elts,
int single_op, int inner_op, int outer_op)
{
Py_ssize_t n = asdl_seq_LEN(elts);
Py_ssize_t i, nsubitems = 0, nseen = 0;
for (i = 0; i < n; i++) {
expr_ty elt = asdl_seq_GET(elts, i);
if (elt->kind == Starred_kind) {
if (nseen) {
ADDOP_I(c, inner_op, nseen);
nseen = 0;
nsubitems++;
}
VISIT(c, expr, elt->v.Starred.value);
nsubitems++;
}
else {
VISIT(c, expr, elt);
nseen++;
}
}
if (nsubitems) {
if (nseen) {
ADDOP_I(c, inner_op, nseen);
nsubitems++;
}
ADDOP_I(c, outer_op, nsubitems);
}
else
ADDOP_I(c, single_op, nseen);
return 1;
}
static int
assignment_helper(struct compiler *c, asdl_seq *elts)
{
Py_ssize_t n = asdl_seq_LEN(elts);
Py_ssize_t i;
int seen_star = 0;
for (i = 0; i < n; i++) {
expr_ty elt = asdl_seq_GET(elts, i);
if (elt->kind == Starred_kind && !seen_star) {
if ((i >= (1 << 8)) ||
(n-i-1 >= (INT_MAX >> 8)))
return compiler_error(c,
"too many expressions in "
"star-unpacking assignment");
ADDOP_I(c, UNPACK_EX, (i + ((n-i-1) << 8)));
seen_star = 1;
asdl_seq_SET(elts, i, elt->v.Starred.value);
}
else if (elt->kind == Starred_kind) {
return compiler_error(c,
"two starred expressions in assignment");
}
}
if (!seen_star) {
ADDOP_I(c, UNPACK_SEQUENCE, n);
}
VISIT_SEQ(c, expr, elts);
return 1;
}
static int
compiler_list(struct compiler *c, expr_ty e)
{
asdl_seq *elts = e->v.List.elts;
if (e->v.List.ctx == Store) {
return assignment_helper(c, elts);
}
else if (e->v.List.ctx == Load) {
return starunpack_helper(c, elts,
BUILD_LIST, BUILD_TUPLE, BUILD_LIST_UNPACK);
}
else
VISIT_SEQ(c, expr, elts);
return 1;
}
static int
compiler_tuple(struct compiler *c, expr_ty e)
{
asdl_seq *elts = e->v.Tuple.elts;
if (e->v.Tuple.ctx == Store) {
return assignment_helper(c, elts);
}
else if (e->v.Tuple.ctx == Load) {
return starunpack_helper(c, elts,
BUILD_TUPLE, BUILD_TUPLE, BUILD_TUPLE_UNPACK);
}
else
VISIT_SEQ(c, expr, elts);
return 1;
}
static int
compiler_set(struct compiler *c, expr_ty e)
{
return starunpack_helper(c, e->v.Set.elts, BUILD_SET,
BUILD_SET, BUILD_SET_UNPACK);
}
static int
are_all_items_const(asdl_seq *seq, Py_ssize_t begin, Py_ssize_t end)
{
Py_ssize_t i;
for (i = begin; i < end; i++) {
expr_ty key = (expr_ty)asdl_seq_GET(seq, i);
if (key == NULL || !is_const(key))
return 0;
}
return 1;
}
static int
compiler_subdict(struct compiler *c, expr_ty e, Py_ssize_t begin, Py_ssize_t end)
{
Py_ssize_t i, n = end - begin;
PyObject *keys, *key;
if (n > 1 && are_all_items_const(e->v.Dict.keys, begin, end)) {
for (i = begin; i < end; i++) {
VISIT(c, expr, (expr_ty)asdl_seq_GET(e->v.Dict.values, i));
}
keys = PyTuple_New(n);
if (keys == NULL) {
return 0;
}
for (i = begin; i < end; i++) {
key = get_const_value((expr_ty)asdl_seq_GET(e->v.Dict.keys, i));
Py_INCREF(key);
PyTuple_SET_ITEM(keys, i - begin, key);
}
ADDOP_LOAD_CONST_NEW(c, keys);
ADDOP_I(c, BUILD_CONST_KEY_MAP, n);
}
else {
for (i = begin; i < end; i++) {
VISIT(c, expr, (expr_ty)asdl_seq_GET(e->v.Dict.keys, i));
VISIT(c, expr, (expr_ty)asdl_seq_GET(e->v.Dict.values, i));
}
ADDOP_I(c, BUILD_MAP, n);
}
return 1;
}
static int
compiler_dict(struct compiler *c, expr_ty e)
{
Py_ssize_t i, n, elements;
int containers;
int is_unpacking = 0;
n = asdl_seq_LEN(e->v.Dict.values);
containers = 0;
elements = 0;
for (i = 0; i < n; i++) {
is_unpacking = (expr_ty)asdl_seq_GET(e->v.Dict.keys, i) == NULL;
if (elements == 0xFFFF || (elements && is_unpacking)) {
if (!compiler_subdict(c, e, i - elements, i))
return 0;
containers++;
elements = 0;
}
if (is_unpacking) {
VISIT(c, expr, (expr_ty)asdl_seq_GET(e->v.Dict.values, i));
containers++;
}
else {
elements++;
}
}
if (elements || containers == 0) {
if (!compiler_subdict(c, e, n - elements, n))
return 0;
containers++;
}
/* If there is more than one dict, they need to be merged into a new
* dict. If there is one dict and it's an unpacking, then it needs
* to be copied into a new dict." */
if (containers > 1 || is_unpacking) {
ADDOP_I(c, BUILD_MAP_UNPACK, containers);