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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 "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
#define IS_TOP_LEVEL_AWAIT(c) ( \
(c->c_flags->cf_flags & PyCF_ALLOW_TOP_LEVEL_AWAIT) \
&& (c->u->u_ste->ste_type == ModuleBlock))
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, TRY_EXCEPT, FINALLY_TRY, FINALLY_END,
WITH, ASYNC_WITH, HANDLER_CLEANUP, POP_VALUE, EXCEPTION_HANDLER };
struct fblockinfo {
enum fblocktype fb_type;
basicblock *fb_block;
/* (optional) type-specific exit or cleanup block */
basicblock *fb_exit;
/* (optional) additional information required for unwinding */
void *fb_datum;
};
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_posonlyargcount; /* number of positional only 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 */
};
/* 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;
int c_do_not_emit_bytecode; /* The compiler won't emit any bytecode
if this value is different from zero.
This can be used to temporarily visit
nodes without emitting bytecode to
check only errors. */
PyObject *c_const_cache; /* Python dict holding all constants,
including names tuple */
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(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_warn(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_subscript(struct compiler *, expr_ty);
static int compiler_slice(struct compiler *, expr_ty);
static int inplace_binop(operator_ty);
static int are_all_items_const(asdl_seq *, Py_ssize_t, Py_ssize_t);
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,
int depth,
expr_ty elt, expr_ty val, int type);
static int compiler_async_comprehension_generator(
struct compiler *c,
asdl_seq *generators, int gen_index,
int depth,
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_const_cache = PyDict_New();
if (!c->c_const_cache) {
return 0;
}
c->c_stack = PyList_New(0);
if (!c->c_stack) {
Py_CLEAR(c->c_const_cache);
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 = _PyCompilerFlags_INIT;
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) {
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_GetConfig()->optimization_level : optimize;
c.c_nestlevel = 0;
c.c_do_not_emit_bytecode = 0;
_PyASTOptimizeState state;
state.optimize = c.c_optimize;
state.ff_features = merged;
if (!_PyAST_Optimize(mod, arena, &state)) {
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_const_cache);
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_Calloc(1, sizeof(
struct compiler_unit));
if (!u) {
PyErr_NoMemory();
return 0;
}
u->u_scope_type = scope_type;
u->u_argcount = 0;
u->u_posonlyargcount = 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_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_Calloc(1, sizeof(basicblock));
if (b == NULL) {
PyErr_NoMemory();
return NULL;
}
/* 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(basicblock *b)
{
assert(b != NULL);
if (b->b_instr == NULL) {
b->b_instr = (struct instr *)PyObject_Calloc(
DEFAULT_BLOCK_SIZE, sizeof(struct instr));
if (b->b_instr == NULL) {
PyErr_NoMemory();
return -1;
}
b->b_ialloc = 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 line number and column offset for the following instructions.
The line number is reset in the following cases:
- when entering a new scope
- on each statement
- on each expression and sub-expression
- before the "except" and "finally" clauses
*/
#define SET_LOC(c, x) \
(c)->u->u_lineno = (x)->lineno; \
(c)->u->u_col_offset = (x)->col_offset;
/* 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 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 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_MAP:
return 1 - 2*oparg;
case BUILD_CONST_KEY_MAP:
return -oparg;
case LOAD_ATTR:
return 0;
case COMPARE_OP:
case IS_OP:
case CONTAINS_OP:
return -1;
case JUMP_IF_NOT_EXC_MATCH:
return -2;
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 RERAISE:
return -3;
case WITH_EXCEPT_START:
return 1;
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;
case LOAD_ASSERTION_ERROR:
return 1;
case LIST_TO_TUPLE:
return 0;
case LIST_EXTEND:
case SET_UPDATE:
case DICT_MERGE:
case DICT_UPDATE:
return -1;
default:
return PY_INVALID_STACK_EFFECT;
}
return PY_INVALID_STACK_EFFECT; /* not reachable */
}
int
PyCompile_OpcodeStackEffectWithJump(int opcode, int oparg, int jump)
{
return stack_effect(opcode, oparg, jump);
}
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));
if (c->c_do_not_emit_bytecode) {
return 1;
}
off = compiler_next_instr(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;
i->i_lineno = c->u->u_lineno;
return 1;
}
static Py_ssize_t
compiler_add_o(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;
}
// Merge const *o* recursively and return constant key object.
static PyObject*
merge_consts_recursive(struct compiler *c, PyObject *o)
{
// None and Ellipsis are singleton, and key is the singleton.
// No need to merge object and key.
if (o == Py_None || o == Py_Ellipsis) {
Py_INCREF(o);
return o;
}
PyObject *key = _PyCode_ConstantKey(o);
if (key == NULL) {
return NULL;
}
// t is borrowed reference
PyObject *t = PyDict_SetDefault(c->c_const_cache, key, key);
if (t != key) {
// o is registered in c_const_cache. Just use it.
Py_XINCREF(t);
Py_DECREF(key);
return t;
}
// We registered o in c_const_cache.
// When o is a tuple or frozenset, we want to merge its
// items too.
if (PyTuple_CheckExact(o)) {
Py_ssize_t len = PyTuple_GET_SIZE(o);
for (Py_ssize_t i = 0; i < len; i++) {
PyObject *item = PyTuple_GET_ITEM(o, i);
PyObject *u = merge_consts_recursive(c, item);
if (u == NULL) {
Py_DECREF(key);
return NULL;
}
// See _PyCode_ConstantKey()
PyObject *v; // borrowed
if (PyTuple_CheckExact(u)) {
v = PyTuple_GET_ITEM(u, 1);
}
else {
v = u;
}
if (v != item) {
Py_INCREF(v);
PyTuple_SET_ITEM(o, i, v);
Py_DECREF(item);
}
Py_DECREF(u);
}
}
else if (PyFrozenSet_CheckExact(o)) {
// *key* is tuple. And its first item is frozenset of
// constant keys.
// See _PyCode_ConstantKey() for detail.
assert(PyTuple_CheckExact(key));
assert(PyTuple_GET_SIZE(key) == 2);
Py_ssize_t len = PySet_GET_SIZE(o);
if (len == 0) { // empty frozenset should not be re-created.
return key;
}
PyObject *tuple = PyTuple_New(len);
if (tuple == NULL) {
Py_DECREF(key);
return NULL;
}
Py_ssize_t i = 0, pos = 0;
PyObject *item;
Py_hash_t hash;
while (_PySet_NextEntry(o, &pos, &item, &hash)) {
PyObject *k = merge_consts_recursive(c, item);
if (k == NULL) {
Py_DECREF(tuple);
Py_DECREF(key);
return NULL;
}
PyObject *u;
if (PyTuple_CheckExact(k)) {
u = PyTuple_GET_ITEM(k, 1);
Py_INCREF(u);
Py_DECREF(k);
}
else {
u = k;
}
PyTuple_SET_ITEM(tuple, i, u); // Steals reference of u.
i++;
}
// Instead of rewriting o, we create new frozenset and embed in the
// key tuple. Caller should get merged frozenset from the key tuple.
PyObject *new = PyFrozenSet_New(tuple);
Py_DECREF(tuple);
if (new == NULL) {
Py_DECREF(key);
return NULL;
}
assert(PyTuple_GET_ITEM(key, 1) == o);
Py_DECREF(o);
PyTuple_SET_ITEM(key, 1, new);
}
return key;
}
static Py_ssize_t
compiler_add_const(struct compiler *c, PyObject *o)
{
if (c->c_do_not_emit_bytecode) {
return 0;
}
PyObject *key = merge_consts_recursive(c, o);
if (key == NULL) {
return -1;
}
Py_ssize_t arg = compiler_add_o(c->u->u_consts, key);
Py_DECREF(key);
return arg;
}
static int
compiler_addop_load_const(struct compiler *c, PyObject *o)
{
if (c->c_do_not_emit_bytecode) {
return 1;
}
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)
{
if (c->c_do_not_emit_bytecode) {
return 1;
}
Py_ssize_t arg = compiler_add_o(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;
if (c->c_do_not_emit_bytecode) {
return 1;
}
PyObject *mangled = _Py_Mangle(c->u->u_private, o);
if (!mangled)
return 0;
arg = compiler_add_o(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;
if (c->c_do_not_emit_bytecode) {
return 1;
}
/* 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->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);
i->i_lineno = c->u->u_lineno;
return 1;
}
static int
compiler_addop_j(struct compiler *c, int opcode, basicblock *b, int absolute)
{
struct instr *i;
int off;
if (c->c_do_not_emit_bytecode) {
return 1;
}
assert(HAS_ARG(opcode));
assert(b != NULL);
off = compiler_next_instr(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;
i->i_lineno = c->u->u_lineno;
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; \
}
#define ADDOP_COMPARE(C, CMP) { \
if (!compiler_addcompare((C), (cmpop_ty)(CMP))) \
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; \
} \
} \
}
/* These macros allows to check only for errors and not emmit bytecode
* while visiting nodes.
*/
#define BEGIN_DO_NOT_EMIT_BYTECODE { \
c->c_do_not_emit_bytecode++;
#define END_DO_NOT_EMIT_BYTECODE \
c->c_do_not_emit_bytecode--; \
}
/* 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, void *datum)
{
struct fblockinfo *f;
if (c->u->u_nfblocks >= CO_MAXBLOCKS) {
return compiler_error(c, "too many statically nested blocks");
}
f = &c->u->u_fblock[c->u->u_nfblocks++];
f->fb_type = t;
f->fb_block = b;
f->fb_exit = exit;
f->fb_datum = datum;
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);
}
static int
compiler_call_exit_with_nones(struct compiler *c) {
ADDOP_O(c, LOAD_CONST, Py_None, consts);
ADDOP(c, DUP_TOP);
ADDOP(c, DUP_TOP);
ADDOP_I(c, CALL_FUNCTION, 3);
return 1;
}
/* Unwind a frame block. If preserve_tos is true, the TOS before
* popping the blocks will be restored afterwards, unless another
* return, break or continue is found. In which case, the TOS will
* be popped.
*/
static int
compiler_unwind_fblock(struct compiler *c, struct fblockinfo *info,
int preserve_tos)
{
switch (info->fb_type) {
case WHILE_LOOP:
case EXCEPTION_HANDLER:
return 1;
case FOR_LOOP:
/* Pop the iterator */
if (preserve_tos) {
ADDOP(c, ROT_TWO);
}
ADDOP(c, POP_TOP);
return 1;
case TRY_EXCEPT:
ADDOP(c, POP_BLOCK);
return 1;
case FINALLY_TRY:
ADDOP(c, POP_BLOCK);
if (preserve_tos) {
if (!compiler_push_fblock(c, POP_VALUE, NULL, NULL, NULL)) {
return 0;
}
}
/* Emit the finally block, restoring the line number when done */
int saved_lineno = c->u->u_lineno;
VISIT_SEQ(c, stmt, info->fb_datum);
c->u->u_lineno = saved_lineno;
if (preserve_tos) {
compiler_pop_fblock(c, POP_VALUE, NULL);
}
return 1;
case FINALLY_END:
if (preserve_tos) {
ADDOP(c, ROT_FOUR);
}
ADDOP(c, POP_TOP);
ADDOP(c, POP_TOP);
ADDOP(c, POP_TOP);
if (preserve_tos) {
ADDOP(c, ROT_FOUR);
}
ADDOP(c, POP_EXCEPT);
return 1;
case WITH:
case ASYNC_WITH:
ADDOP(c, POP_BLOCK);
if (preserve_tos) {
ADDOP(c, ROT_TWO);
}
if(!compiler_call_exit_with_nones(c)) {
return 0;
}
if (info->fb_type == ASYNC_WITH) {
ADDOP(c, GET_AWAITABLE);
ADDOP_LOAD_CONST(c, Py_None);
ADDOP(c, YIELD_FROM);
}
ADDOP(c, POP_TOP);
return 1;
case HANDLER_CLEANUP:
if (info->fb_datum) {
ADDOP(c, POP_BLOCK);
}
if (preserve_tos) {
ADDOP(c, ROT_FOUR);
}
ADDOP(c, POP_EXCEPT);
if (info->fb_datum) {
ADDOP_LOAD_CONST(c, Py_None);
compiler_nameop(c, info->fb_datum, Store);
compiler_nameop(c, info->fb_datum, Del);
}
return 1;
case POP_VALUE:
if (preserve_tos) {
ADDOP(c, ROT_TWO);
}
ADDOP(c, POP_TOP);
return 1;
}
Py_UNREACHABLE();
}
/** Unwind block stack. If loop is not NULL, then stop when the first loop is encountered. */
static int
compiler_unwind_fblock_stack(struct compiler *c, int preserve_tos, struct fblockinfo **loop) {
if (c->u->u_nfblocks == 0) {
return 1;
}
struct fblockinfo *top = &c->u->u_fblock[c->u->u_nfblocks-1];
if (loop != NULL && (top->fb_type == WHILE_LOOP || top->fb_type == FOR_LOOP)) {
*loop = top;
return 1;
}
struct fblockinfo copy = *top;
c->u->u_nfblocks--;
if (!compiler_unwind_fblock(c, &copy, preserve_tos)) {
return 0;
}
if (!compiler_unwind_fblock_stack(c, preserve_tos, loop)) {
return 0;
}
c->u->u_fblock[c->u->u_nfblocks] = copy;
c->u->u_nfblocks++;
return 1;
}
/* 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 empty, then lineno will be set later in assemble. */
if (c->u->u_scope_type == COMPILER_SCOPE_MODULE && asdl_seq_LEN(stmts)) {
st = (stmt_ty)asdl_seq_GET(stmts, 0);
SET_LOC(c, st);
}
/* 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;
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) {
_Py_FatalErrorFormat(__func__,
"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)));
}
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 lookup 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) {
_Py_FatalErrorFormat(__func__,
"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)));
}
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 (!compiler_visit_argannotations(c, args->posonlyargs, 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
forbidden_name(struct compiler *c, identifier name, expr_context_ty ctx)
{
if (ctx == Store && _PyUnicode_EqualToASCIIString(name, "__debug__")) {
compiler_error(c, "cannot assign to __debug__");
return 1;
}
return 0;
}
static int
compiler_check_debug_one_arg(struct compiler *c, arg_ty arg)
{
if (arg != NULL) {
if (forbidden_name(c, arg->arg, Store))
return 0;
}
return 1;
}
static int
compiler_check_debug_args_seq(struct compiler *c, asdl_seq *args)
{
if (args != NULL) {
for (Py_ssize_t i = 0, n = asdl_seq_LEN(args); i < n; i++) {
if (!compiler_check_debug_one_arg(c, asdl_seq_GET(args, i)))
return 0;
}
}
return 1;
}
static int
compiler_check_debug_args(struct compiler *c, arguments_ty args)
{
if (!compiler_check_debug_args_seq(c, args->posonlyargs))
return 0;
if (!compiler_check_debug_args_seq(c, args->args))
return 0;
if (!compiler_check_debug_one_arg(c, args->vararg))
return 0;
if (!compiler_check_debug_args_seq(c, args->kwonlyargs))
return 0;
if (!compiler_check_debug_one_arg(c, args->kwarg))
return 0;
return 1;
}
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;
int firstlineno;
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_check_debug_args(c, args))
return 0;
if (!compiler_decorators(c, decos))
return 0;
firstlineno = s->lineno;
if (asdl_seq_LEN(decos)) {
firstlineno = ((expr_ty)asdl_seq_GET(decos, 0))->lineno;
}
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, firstlineno)) {
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_posonlyargcount = asdl_seq_LEN(args->posonlyargs);
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, firstlineno;
asdl_seq* decos = s->v.ClassDef.decorator_list;
if (!compiler_decorators(c, decos))
return 0;
firstlineno = s->lineno;
if (asdl_seq_LEN(decos)) {
firstlineno = ((expr_ty)asdl_seq_GET(decos, 0))->lineno;
}
/* ultimately generate code for:
<name> = __build_class__(<func>, <name>, *<bases>, **<keywords>)
where:
<func> is a zero arg function/closure created from the class body.
It mutates its locals to build the class namespace.
<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, firstlineno))
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;
}
/* Return 0 if the expression is a constant value except named singletons.
Return 1 otherwise. */
static int
check_is_arg(expr_ty e)
{
if (e->kind != Constant_kind) {
return 1;
}
PyObject *value = e->v.Constant.value;
return (value == Py_None
|| value == Py_False
|| value == Py_True
|| value == Py_Ellipsis);
}
/* Check operands of identity chacks ("is" and "is not").
Emit a warning if any operand is a constant except named singletons.
Return 0 on error.
*/
static int
check_compare(struct compiler *c, expr_ty e)
{
Py_ssize_t i, n;
int left = check_is_arg(e->v.Compare.left);
n = asdl_seq_LEN(e->v.Compare.ops);
for (i = 0; i < n; i++) {
cmpop_ty op = (cmpop_ty)asdl_seq_GET(e->v.Compare.ops, i);
int right = check_is_arg((expr_ty)asdl_seq_GET(e->v.Compare.comparators, i));
if (op == Is || op == IsNot) {
if (!right || !left) {
const char *msg = (op == Is)
? "\"is\" with a literal. Did you mean \"==\"?"
: "\"is not\" with a literal. Did you mean \"!=\"?";
return compiler_warn(c, msg);
}
}
left = right;
}
return 1;
}
static int compiler_addcompare(struct compiler *c, cmpop_ty op)
{
int cmp;
switch (op) {
case Eq:
cmp = Py_EQ;
break;
case NotEq:
cmp = Py_NE;
break;
case Lt:
cmp = Py_LT;
break;
case LtE:
cmp = Py_LE;
break;
case Gt:
cmp = Py_GT;
break;
case GtE:
cmp = Py_GE;
break;
case Is:
ADDOP_I(c, IS_OP, 0);
return 1;
case IsNot:
ADDOP_I(c, IS_OP, 1);
return 1;
case In:
ADDOP_I(c, CONTAINS_OP, 0);
return 1;
case NotIn:
ADDOP_I(c, CONTAINS_OP, 1);
return 1;
default:
Py_UNREACHABLE();
}
ADDOP_I(c, COMPARE_OP, cmp);
return 1;
}
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) {
if (!check_compare(c, e)) {
return 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_COMPARE(c, 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_COMPARE(c, 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 (!compiler_check_debug_args(c, args))
return 0;
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_posonlyargcount = asdl_seq_LEN(args->posonlyargs);
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) {
BEGIN_DO_NOT_EMIT_BYTECODE
VISIT_SEQ(c, stmt, s->v.If.body);
END_DO_NOT_EMIT_BYTECODE
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);
if (s->v.If.orelse) {
BEGIN_DO_NOT_EMIT_BYTECODE
VISIT_SEQ(c, stmt, s->v.If.orelse);
END_DO_NOT_EMIT_BYTECODE
}
} 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, NULL)) {
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 (IS_TOP_LEVEL_AWAIT(c)){
c->u->u_ste->ste_coroutine = 1;
} else 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, NULL)) {
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);
/* We don't want to trace the END_ASYNC_FOR, so make sure
* that it has the same lineno as the following instruction. */
if (asdl_seq_LEN(s->v.For.orelse)) {
SET_LOC(c, (stmt_ty)asdl_seq_GET(s->v.For.orelse, 0));
}
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) {
BEGIN_DO_NOT_EMIT_BYTECODE
// Push a dummy block so the VISIT_SEQ knows that we are
// inside a while loop so it can correctly evaluate syntax
// errors.
if (!compiler_push_fblock(c, WHILE_LOOP, NULL, NULL, NULL)) {
return 0;
}
VISIT_SEQ(c, stmt, s->v.While.body);
// Remove the dummy block now that is not needed.
compiler_pop_fblock(c, WHILE_LOOP, NULL);
END_DO_NOT_EMIT_BYTECODE
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, NULL))
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) &&
(s->v.Return.value->kind != Constant_kind));
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);
}
if (!compiler_unwind_fblock_stack(c, preserve_tos, NULL))
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)
{
struct fblockinfo *loop = NULL;
if (!compiler_unwind_fblock_stack(c, 0, &loop)) {
return 0;
}
if (loop == NULL) {
return compiler_error(c, "'break' outside loop");
}
if (!compiler_unwind_fblock(c, loop, 0)) {
return 0;
}
ADDOP_JABS(c, JUMP_ABSOLUTE, loop->fb_exit);
return 1;
}
static int
compiler_continue(struct compiler *c)
{
struct fblockinfo *loop = NULL;
if (!compiler_unwind_fblock_stack(c, 0, &loop)) {
return 0;
}
if (loop == NULL) {
return compiler_error(c, "'continue' not properly in loop");
}
ADDOP_JABS(c, JUMP_ABSOLUTE, loop->fb_block);
return 1;
}
/* Code generated for "try: <body> finally: <finalbody>" is as follows:
SETUP_FINALLY L
<code for body>
POP_BLOCK
<code for finalbody>
JUMP E
L:
<code for finalbody>
E:
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.
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, *exit;
body = compiler_new_block(c);
end = compiler_new_block(c);
exit = compiler_new_block(c);
if (body == NULL || end == NULL || exit == 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, s->v.Try.finalbody))
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);
compiler_pop_fblock(c, FINALLY_TRY, body);
VISIT_SEQ(c, stmt, s->v.Try.finalbody);
ADDOP_JREL(c, JUMP_FORWARD, exit);
/* `finally` block */
compiler_use_next_block(c, end);
if (!compiler_push_fblock(c, FINALLY_END, end, NULL, NULL))
return 0;
VISIT_SEQ(c, stmt, s->v.Try.finalbody);
compiler_pop_fblock(c, FINALLY_END, end);
ADDOP(c, RERAISE);
compiler_use_next_block(c, exit);
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] JUMP_IF_NOT_EXC_MATCH L2 ) only if E1
[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: RERAISE # 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, TRY_EXCEPT, body, NULL, NULL))
return 0;
VISIT_SEQ(c, stmt, s->v.Try.body);
ADDOP(c, POP_BLOCK);
compiler_pop_fblock(c, TRY_EXCEPT, body);
ADDOP_JREL(c, JUMP_FORWARD, orelse);
n = asdl_seq_LEN(s->v.Try.handlers);
compiler_use_next_block(c, except);
/* Runtime will push a block here, so we need to account for that */
if (!compiler_push_fblock(c, EXCEPTION_HANDLER, NULL, NULL, NULL))
return 0;
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");
SET_LOC(c, handler);
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_JABS</