/*********************************************************** Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam, The Netherlands. All Rights Reserved Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation, and that the names of Stichting Mathematisch Centrum or CWI or Corporation for National Research Initiatives or CNRI not be used in advertising or publicity pertaining to distribution of the software without specific, written prior permission. While CWI is the initial source for this software, a modified version is made available by the Corporation for National Research Initiatives (CNRI) at the Internet address ftp://ftp.python.org. STICHTING MATHEMATISCH CENTRUM AND CNRI DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM OR CNRI BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. ******************************************************************/ /* Compile an expression node to intermediate code */ /* XXX TO DO: XXX add __doc__ attribute == co_doc to code object attributes? XXX (it's currently the first item of the co_const tuple) XXX Generate simple jump for break/return outside 'try...finally' XXX Allow 'continue' inside try-finally XXX get rid of SET_LINENO instructions, use JAR's table trick XXX (need an option to put them back in, for debugger!) XXX New 1-byte opcode for loading None XXX New opcode for loading the initial index for a for loop XXX other JAR tricks? */ #ifndef NO_PRIVATE_NAME_MANGLING #define PRIVATE_NAME_MANGLING #endif #include "allobjects.h" #include "node.h" #include "token.h" #include "graminit.h" #include "compile.h" #include "opcode.h" #include "structmember.h" #include #include #define OP_DELETE 0 #define OP_ASSIGN 1 #define OP_APPLY 2 #define OFF(x) offsetof(codeobject, x) static struct memberlist code_memberlist[] = { {"co_argcount", T_INT, OFF(co_argcount), READONLY}, {"co_nlocals", T_INT, OFF(co_nlocals), READONLY}, {"co_stacksize",T_INT, OFF(co_stacksize), READONLY}, {"co_flags", T_INT, OFF(co_flags), READONLY}, {"co_code", T_OBJECT, OFF(co_code), READONLY}, {"co_consts", T_OBJECT, OFF(co_consts), READONLY}, {"co_names", T_OBJECT, OFF(co_names), READONLY}, {"co_varnames", T_OBJECT, OFF(co_varnames), READONLY}, {"co_filename", T_OBJECT, OFF(co_filename), READONLY}, {"co_name", T_OBJECT, OFF(co_name), READONLY}, {NULL} /* Sentinel */ }; static object * code_getattr(co, name) codeobject *co; char *name; { return getmember((char *)co, code_memberlist, name); } static void code_dealloc(co) codeobject *co; { XDECREF(co->co_code); XDECREF(co->co_consts); XDECREF(co->co_names); XDECREF(co->co_filename); XDECREF(co->co_name); XDECREF(co->co_varnames); DEL(co); } static object * code_repr(co) codeobject *co; { char buf[500]; int lineno = -1; char *p = GETSTRINGVALUE(co->co_code); char *filename = "???"; char *name = "???"; if (*p == SET_LINENO) lineno = (p[1] & 0xff) | ((p[2] & 0xff) << 8); if (co->co_filename && is_stringobject(co->co_filename)) filename = getstringvalue(co->co_filename); if (co->co_name && is_stringobject(co->co_name)) name = getstringvalue(co->co_name); sprintf(buf, "", name, (long)co, filename, lineno); return newstringobject(buf); } static int code_compare(co, cp) codeobject *co, *cp; { int cmp; cmp = cp->co_argcount - cp->co_argcount; if (cmp) return cmp; cmp = cp->co_nlocals - cp->co_nlocals; if (cmp) return cmp; cmp = cp->co_flags - cp->co_flags; if (cmp) return cmp; cmp = cmpobject((object *)co->co_code, (object *)cp->co_code); if (cmp) return cmp; cmp = cmpobject(co->co_consts, cp->co_consts); if (cmp) return cmp; cmp = cmpobject(co->co_names, cp->co_names); if (cmp) return cmp; cmp = cmpobject(co->co_varnames, cp->co_varnames); return cmp; } static long code_hash(co) codeobject *co; { long h, h1, h2, h3, h4; h1 = hashobject((object *)co->co_code); if (h1 == -1) return -1; h2 = hashobject(co->co_consts); if (h2 == -1) return -1; h3 = hashobject(co->co_names); if (h3 == -1) return -1; h4 = hashobject(co->co_varnames); if (h4 == -1) return -1; h = h1 ^ h2 ^ h3 ^ h4 ^ co->co_argcount ^ co->co_nlocals ^ co->co_flags; if (h == -1) h = -2; return h; } typeobject Codetype = { OB_HEAD_INIT(&Typetype) 0, "code", sizeof(codeobject), 0, (destructor)code_dealloc, /*tp_dealloc*/ 0, /*tp_print*/ (getattrfunc)code_getattr, /*tp_getattr*/ 0, /*tp_setattr*/ (cmpfunc)code_compare, /*tp_compare*/ (reprfunc)code_repr, /*tp_repr*/ 0, /*tp_as_number*/ 0, /*tp_as_sequence*/ 0, /*tp_as_mapping*/ (hashfunc)code_hash, /*tp_hash*/ }; codeobject * newcodeobject(argcount, nlocals, stacksize, flags, code, consts, names, varnames, filename, name) int argcount; int nlocals; int stacksize; int flags; object *code; object *consts; object *names; object *varnames; object *filename; object *name; { codeobject *co; int i; /* Check argument types */ if (argcount < 0 || nlocals < 0 || code == NULL || !is_stringobject(code) || consts == NULL || !is_tupleobject(consts) || names == NULL || !is_tupleobject(names) || varnames == NULL || !is_tupleobject(varnames) || name == NULL || !is_stringobject(name) || filename == NULL || !is_stringobject(filename)) { err_badcall(); return NULL; } /* Make sure names and varnames are all strings */ for (i = gettuplesize(names); --i >= 0; ) { object *v = gettupleitem(names, i); if (v == NULL || !is_stringobject(v)) { err_badcall(); return NULL; } } for (i = gettuplesize(varnames); --i >= 0; ) { object *v = gettupleitem(varnames, i); if (v == NULL || !is_stringobject(v)) { err_badcall(); return NULL; } } co = NEWOBJ(codeobject, &Codetype); if (co != NULL) { co->co_argcount = argcount; co->co_nlocals = nlocals; co->co_stacksize = stacksize; co->co_flags = flags; INCREF(code); co->co_code = (stringobject *)code; INCREF(consts); co->co_consts = consts; INCREF(names); co->co_names = names; INCREF(varnames); co->co_varnames = varnames; INCREF(filename); co->co_filename = filename; INCREF(name); co->co_name = name; } return co; } /* Data structure used internally */ struct compiling { object *c_code; /* string */ object *c_consts; /* list of objects */ object *c_names; /* list of strings (names) */ object *c_globals; /* dictionary (value=None) */ object *c_locals; /* dictionary (value=localID) */ object *c_varnames; /* list (inverse of c_locals) */ int c_nlocals; /* index of next local */ int c_argcount; /* number of top-level arguments */ int c_flags; /* same as co_flags */ int c_nexti; /* index into c_code */ int c_errors; /* counts errors occurred */ int c_infunction; /* set when compiling a function */ int c_interactive; /* generating code for interactive command */ int c_loops; /* counts nested loops */ int c_begin; /* begin of current loop, for 'continue' */ int c_block[CO_MAXBLOCKS]; /* stack of block types */ int c_nblocks; /* current block stack level */ char *c_filename; /* filename of current node */ char *c_name; /* name of object (e.g. function) */ int c_lineno; /* Current line number */ int c_stacklevel; /* Current stack level */ int c_maxstacklevel; /* Maximum stack level */ #ifdef PRIVATE_NAME_MANGLING char *c_private; /* for private name mangling */ #endif }; /* Error message including line number */ static void com_error(c, exc, msg) struct compiling *c; object *exc; char *msg; { int n = strlen(msg); object *v; char buffer[30]; char *s; c->c_errors++; if (c->c_lineno <= 1) { /* Unknown line number or single interactive command */ err_setstr(exc, msg); return; } sprintf(buffer, " (line %d)", c->c_lineno); v = newsizedstringobject((char *)NULL, n + strlen(buffer)); if (v == NULL) return; /* MemoryError, too bad */ s = GETSTRINGVALUE((stringobject *)v); strcpy(s, msg); strcat(s, buffer); err_setval(exc, v); DECREF(v); } /* Interface to the block stack */ static void block_push(c, type) struct compiling *c; int type; { if (c->c_nblocks >= CO_MAXBLOCKS) { com_error(c, SystemError, "too many statically nested blocks"); } else { c->c_block[c->c_nblocks++] = type; } } static void block_pop(c, type) struct compiling *c; int type; { if (c->c_nblocks > 0) c->c_nblocks--; if (c->c_block[c->c_nblocks] != type && c->c_errors == 0) { com_error(c, SystemError, "bad block pop"); } } /* Prototype forward declarations */ static int com_init PROTO((struct compiling *, char *)); static void com_free PROTO((struct compiling *)); static void com_push PROTO((struct compiling *, int)); static void com_pop PROTO((struct compiling *, int)); static void com_done PROTO((struct compiling *)); static void com_node PROTO((struct compiling *, struct _node *)); static void com_factor PROTO((struct compiling *, struct _node *)); static void com_addbyte PROTO((struct compiling *, int)); static void com_addint PROTO((struct compiling *, int)); static void com_addoparg PROTO((struct compiling *, int, int)); static void com_addfwref PROTO((struct compiling *, int, int *)); static void com_backpatch PROTO((struct compiling *, int)); static int com_add PROTO((struct compiling *, object *, object *)); static int com_addconst PROTO((struct compiling *, object *)); static int com_addname PROTO((struct compiling *, object *)); static void com_addopname PROTO((struct compiling *, int, node *)); static void com_list PROTO((struct compiling *, node *, int)); static int com_argdefs PROTO((struct compiling *, node *)); static int com_newlocal PROTO((struct compiling *, char *)); static codeobject *icompile PROTO((struct _node *, struct compiling *)); static codeobject *jcompile PROTO((struct _node *, char *, struct compiling *)); static int com_init(c, filename) struct compiling *c; char *filename; { if ((c->c_code = newsizedstringobject((char *)NULL, 1000)) == NULL) goto fail_3; if ((c->c_consts = newlistobject(0)) == NULL) goto fail_2; if ((c->c_names = newlistobject(0)) == NULL) goto fail_1; if ((c->c_globals = newdictobject()) == NULL) goto fail_0; if ((c->c_locals = newdictobject()) == NULL) goto fail_00; if ((c->c_varnames = newlistobject(0)) == NULL) goto fail_000; c->c_nlocals = 0; c->c_argcount = 0; c->c_flags = 0; c->c_nexti = 0; c->c_errors = 0; c->c_infunction = 0; c->c_interactive = 0; c->c_loops = 0; c->c_begin = 0; c->c_nblocks = 0; c->c_filename = filename; c->c_name = "?"; c->c_lineno = 0; c->c_stacklevel = 0; c->c_maxstacklevel = 0; return 1; fail_000: DECREF(c->c_locals); fail_00: DECREF(c->c_globals); fail_0: DECREF(c->c_names); fail_1: DECREF(c->c_consts); fail_2: DECREF(c->c_code); fail_3: return 0; } static void com_free(c) struct compiling *c; { XDECREF(c->c_code); XDECREF(c->c_consts); XDECREF(c->c_names); XDECREF(c->c_globals); XDECREF(c->c_locals); XDECREF(c->c_varnames); } static void com_push(c, n) struct compiling *c; int n; { c->c_stacklevel += n; if (c->c_stacklevel > c->c_maxstacklevel) c->c_maxstacklevel = c->c_stacklevel; } static void com_pop(c, n) struct compiling *c; int n; { if (c->c_stacklevel < n) { fprintf(stderr, "%s:%d: underflow! nexti=%d, level=%d, n=%d\n", c->c_filename, c->c_lineno, c->c_nexti, c->c_stacklevel, n); c->c_stacklevel = 0; } else c->c_stacklevel -= n; } static void com_done(c) struct compiling *c; { if (c->c_code != NULL) resizestring(&c->c_code, c->c_nexti); } static void com_addbyte(c, byte) struct compiling *c; int byte; { int len; /*fprintf(stderr, "%3d: %3d\n", c->c_nexti, byte);*/ if (byte < 0 || byte > 255) { /* fprintf(stderr, "XXX compiling bad byte: %d\n", byte); fatal("com_addbyte: byte out of range"); */ com_error(c, SystemError, "com_addbyte: byte out of range"); } if (c->c_code == NULL) return; len = getstringsize(c->c_code); if (c->c_nexti >= len) { if (resizestring(&c->c_code, len+1000) != 0) { c->c_errors++; return; } } getstringvalue(c->c_code)[c->c_nexti++] = byte; } static void com_addint(c, x) struct compiling *c; int x; { com_addbyte(c, x & 0xff); com_addbyte(c, x >> 8); /* XXX x should be positive */ } static void com_addoparg(c, op, arg) struct compiling *c; int op; int arg; { if (op == SET_LINENO) c->c_lineno = arg; com_addbyte(c, op); com_addint(c, arg); } static void com_addfwref(c, op, p_anchor) struct compiling *c; int op; int *p_anchor; { /* Compile a forward reference for backpatching */ int here; int anchor; com_addbyte(c, op); here = c->c_nexti; anchor = *p_anchor; *p_anchor = here; com_addint(c, anchor == 0 ? 0 : here - anchor); } static void com_backpatch(c, anchor) struct compiling *c; int anchor; /* Must be nonzero */ { unsigned char *code = (unsigned char *) getstringvalue(c->c_code); int target = c->c_nexti; int dist; int prev; for (;;) { /* Make the JUMP instruction at anchor point to target */ prev = code[anchor] + (code[anchor+1] << 8); dist = target - (anchor+2); code[anchor] = dist & 0xff; code[anchor+1] = dist >> 8; if (!prev) break; anchor -= prev; } } /* Handle literals and names uniformly */ static int com_add(c, list, v) struct compiling *c; object *list; object *v; { int n = getlistsize(list); int i; for (i = n; --i >= 0; ) { object *w = getlistitem(list, i); if (v->ob_type == w->ob_type && cmpobject(v, w) == 0) return i; } if (addlistitem(list, v) != 0) c->c_errors++; return n; } static int com_addconst(c, v) struct compiling *c; object *v; { return com_add(c, c->c_consts, v); } static int com_addname(c, v) struct compiling *c; object *v; { return com_add(c, c->c_names, v); } #ifdef PRIVATE_NAME_MANGLING static int com_mangle(c, name, buffer, maxlen) struct compiling *c; char *name; char *buffer; int maxlen; { /* Name mangling: __private becomes _classname__private. This is independent from how the name is used. */ char *p; int nlen, plen; nlen = strlen(name); if (nlen+2 >= maxlen) return 0; /* Don't mangle __extremely_long_names */ if (name[nlen-1] == '_' && name[nlen-2] == '_') return 0; /* Don't mangle __whatever__ */ p = c->c_private; /* Strip leading underscores from class name */ while (*p == '_') p++; if (*p == '\0') return 0; /* Don't mangle if class is just underscores */ plen = strlen(p); if (plen + nlen >= maxlen) plen = maxlen-nlen-2; /* Truncate class name if too long */ /* buffer = "_" + p[:plen] + name # i.e. 1+plen+nlen bytes */ buffer[0] = '_'; strncpy(buffer+1, p, plen); strcpy(buffer+1+plen, name); /* fprintf(stderr, "mangle %s -> %s\n", name, buffer); */ return 1; } #endif static void com_addopnamestr(c, op, name) struct compiling *c; int op; char *name; { object *v; int i; #ifdef PRIVATE_NAME_MANGLING char buffer[256]; if (name != NULL && name[0] == '_' && name[1] == '_' && c->c_private != NULL && com_mangle(c, name, buffer, (int)sizeof(buffer))) name = buffer; #endif if (name == NULL || (v = newstringobject(name)) == NULL) { c->c_errors++; i = 255; } else { i = com_addname(c, v); DECREF(v); } /* Hack to replace *_NAME opcodes by *_GLOBAL if necessary */ switch (op) { case LOAD_NAME: case STORE_NAME: case DELETE_NAME: if (dictlookup(c->c_globals, name) != NULL) { switch (op) { case LOAD_NAME: op = LOAD_GLOBAL; break; case STORE_NAME: op = STORE_GLOBAL; break; case DELETE_NAME: op = DELETE_GLOBAL; break; } } } com_addoparg(c, op, i); } static void com_addopname(c, op, n) struct compiling *c; int op; node *n; { char *name; char buffer[1000]; /* XXX it is possible to write this code without the 1000 chars on the total length of dotted names, I just can't be bothered right now */ if (TYPE(n) == STAR) name = "*"; else if (TYPE(n) == dotted_name) { char *p = buffer; int i; name = buffer; for (i = 0; i < NCH(n); i += 2) { char *s = STR(CHILD(n, i)); if (p + strlen(s) > buffer + (sizeof buffer) - 2) { com_error(c, MemoryError, "dotted_name too long"); name = NULL; break; } if (p != buffer) *p++ = '.'; strcpy(p, s); p = strchr(p, '\0'); } } else { REQ(n, NAME); name = STR(n); } com_addopnamestr(c, op, name); } static object * parsenumber(co, s) struct compiling *co; char *s; { extern long mystrtol PROTO((const char *, char **, int)); extern unsigned long mystrtoul PROTO((const char *, char **, int)); extern double atof PROTO((const char *)); char *end; long x; #ifndef WITHOUT_COMPLEX Py_complex c; int imflag; #endif errno = 0; end = s + strlen(s) - 1; #ifndef WITHOUT_COMPLEX imflag = *end == 'j' || *end == 'J'; #endif if (*end == 'l' || *end == 'L') return long_scan(s, 0); if (s[0] == '0') x = (long) mystrtoul(s, &end, 0); else x = mystrtol(s, &end, 0); if (*end == '\0') { if (errno != 0) { com_error(co, OverflowError, "integer literal too large"); return NULL; } return newintobject(x); } /* XXX Huge floats may silently fail */ #ifndef WITHOUT_COMPLEX if (imflag) { c.real = 0.; c.imag = atof(s); return newcomplexobject(c); } else #endif return newfloatobject(atof(s)); } static object * parsestr(s) char *s; { object *v; int len; char *buf; char *p; char *end; int c; int quote = *s; if (quote != '\'' && quote != '\"') { err_badcall(); return NULL; } s++; len = strlen(s); if (s[--len] != quote) { err_badcall(); return NULL; } if (len >= 4 && s[0] == quote && s[1] == quote) { s += 2; len -= 2; if (s[--len] != quote || s[--len] != quote) { err_badcall(); return NULL; } } if (strchr(s, '\\') == NULL) return newsizedstringobject(s, len); v = newsizedstringobject((char *)NULL, len); p = buf = getstringvalue(v); end = s + len; while (s < end) { if (*s != '\\') { *p++ = *s++; continue; } s++; switch (*s++) { /* XXX This assumes ASCII! */ case '\n': break; case '\\': *p++ = '\\'; break; case '\'': *p++ = '\''; break; case '\"': *p++ = '\"'; break; case 'b': *p++ = '\b'; break; case 'f': *p++ = '\014'; break; /* FF */ case 't': *p++ = '\t'; break; case 'n': *p++ = '\n'; break; case 'r': *p++ = '\r'; break; case 'v': *p++ = '\013'; break; /* VT */ case 'a': *p++ = '\007'; break; /* BEL, not classic C */ case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': c = s[-1] - '0'; if ('0' <= *s && *s <= '7') { c = (c<<3) + *s++ - '0'; if ('0' <= *s && *s <= '7') c = (c<<3) + *s++ - '0'; } *p++ = c; break; case 'x': if (isxdigit(Py_CHARMASK(*s))) { sscanf(s, "%x", &c); *p++ = c; do { s++; } while (isxdigit(Py_CHARMASK(*s))); break; } /* FALLTHROUGH */ default: *p++ = '\\'; *p++ = s[-1]; break; } } resizestring(&v, (int)(p - buf)); return v; } static object * parsestrplus(n) node *n; { object *v; int i; REQ(CHILD(n, 0), STRING); if ((v = parsestr(STR(CHILD(n, 0)))) != NULL) { /* String literal concatenation */ for (i = 1; i < NCH(n) && v != NULL; i++) { joinstring_decref(&v, parsestr(STR(CHILD(n, i)))); } } return v; } static void com_list_constructor(c, n) struct compiling *c; node *n; { int len; int i; if (TYPE(n) != testlist) REQ(n, exprlist); /* exprlist: expr (',' expr)* [',']; likewise for testlist */ len = (NCH(n) + 1) / 2; for (i = 0; i < NCH(n); i += 2) com_node(c, CHILD(n, i)); com_addoparg(c, BUILD_LIST, len); com_pop(c, len-1); } static void com_dictmaker(c, n) struct compiling *c; node *n; { int i; /* dictmaker: test ':' test (',' test ':' value)* [','] */ for (i = 0; i+2 < NCH(n); i += 4) { /* We must arrange things just right for STORE_SUBSCR. It wants the stack to look like (value) (dict) (key) */ com_addbyte(c, DUP_TOP); com_push(c, 1); com_node(c, CHILD(n, i+2)); /* value */ com_addbyte(c, ROT_TWO); com_node(c, CHILD(n, i)); /* key */ com_addbyte(c, STORE_SUBSCR); com_pop(c, 3); } } static void com_atom(c, n) struct compiling *c; node *n; { node *ch; object *v; int i; REQ(n, atom); ch = CHILD(n, 0); switch (TYPE(ch)) { case LPAR: if (TYPE(CHILD(n, 1)) == RPAR) { com_addoparg(c, BUILD_TUPLE, 0); com_push(c, 1); } else com_node(c, CHILD(n, 1)); break; case LSQB: if (TYPE(CHILD(n, 1)) == RSQB) { com_addoparg(c, BUILD_LIST, 0); com_push(c, 1); } else com_list_constructor(c, CHILD(n, 1)); break; case LBRACE: /* '{' [dictmaker] '}' */ com_addoparg(c, BUILD_MAP, 0); com_push(c, 1); if (TYPE(CHILD(n, 1)) != RBRACE) com_dictmaker(c, CHILD(n, 1)); break; case BACKQUOTE: com_node(c, CHILD(n, 1)); com_addbyte(c, UNARY_CONVERT); break; case NUMBER: if ((v = parsenumber(c, STR(ch))) == NULL) { i = 255; } else { i = com_addconst(c, v); DECREF(v); } com_addoparg(c, LOAD_CONST, i); com_push(c, 1); break; case STRING: v = parsestrplus(n); if (v == NULL) { c->c_errors++; i = 255; } else { i = com_addconst(c, v); DECREF(v); } com_addoparg(c, LOAD_CONST, i); com_push(c, 1); break; case NAME: com_addopname(c, LOAD_NAME, ch); com_push(c, 1); break; default: /* XXX fprintf(stderr, "node type %d\n", TYPE(ch)); */ com_error(c, SystemError, "com_atom: unexpected node type"); } } static void com_slice(c, n, op) struct compiling *c; node *n; int op; { if (NCH(n) == 1) { com_addbyte(c, op); } else if (NCH(n) == 2) { if (TYPE(CHILD(n, 0)) != COLON) { com_node(c, CHILD(n, 0)); com_addbyte(c, op+1); } else { com_node(c, CHILD(n, 1)); com_addbyte(c, op+2); } com_pop(c, 1); } else { com_node(c, CHILD(n, 0)); com_node(c, CHILD(n, 2)); com_addbyte(c, op+3); com_pop(c, 2); } } static void com_argument(c, n, pkeywords) struct compiling *c; node *n; /* argument */ object **pkeywords; { node *m; REQ(n, argument); /* [test '='] test; really [keyword '='] test */ if (NCH(n) == 1) { if (*pkeywords != NULL) { com_error(c, SyntaxError, "non-keyword arg after keyword arg"); } else { com_node(c, CHILD(n, 0)); } return; } m = n; do { m = CHILD(m, 0); } while (NCH(m) == 1); if (TYPE(m) != NAME) { com_error(c, SyntaxError, "keyword can't be an expression"); } else { object *v = newstringobject(STR(m)); if (v != NULL && *pkeywords == NULL) *pkeywords = newdictobject(); if (v == NULL || *pkeywords == NULL) c->c_errors++; else { if (dict2lookup(*pkeywords, v) != NULL) com_error(c, SyntaxError, "duplicate keyword argument"); else if (dict2insert(*pkeywords, v, v) != 0) c->c_errors++; com_addoparg(c, LOAD_CONST, com_addconst(c, v)); com_push(c, 1); DECREF(v); } } com_node(c, CHILD(n, 2)); } static void com_call_function(c, n) struct compiling *c; node *n; /* EITHER arglist OR ')' */ { if (TYPE(n) == RPAR) { com_addoparg(c, CALL_FUNCTION, 0); } else { object *keywords = NULL; int i, na, nk; REQ(n, arglist); na = 0; nk = 0; for (i = 0; i < NCH(n); i += 2) { com_argument(c, CHILD(n, i), &keywords); if (keywords == NULL) na++; else nk++; } XDECREF(keywords); if (na > 255 || nk > 255) { com_error(c, SyntaxError, "more than 255 arguments"); } com_addoparg(c, CALL_FUNCTION, na | (nk << 8)); com_pop(c, na + 2*nk); } } static void com_select_member(c, n) struct compiling *c; node *n; { com_addopname(c, LOAD_ATTR, n); } static void com_sliceobj(c, n) struct compiling *c; node *n; { int i=0; int ns=2; /* number of slice arguments */ node *ch; /* first argument */ if (TYPE(CHILD(n,i)) == COLON) { com_addoparg(c, LOAD_CONST, com_addconst(c, None)); com_push(c, 1); i++; } else { com_node(c, CHILD(n,i)); i++; REQ(CHILD(n,i),COLON); i++; } /* second argument */ if (i < NCH(n) && TYPE(CHILD(n,i)) == test) { com_node(c, CHILD(n,i)); i++; } else { com_addoparg(c, LOAD_CONST, com_addconst(c, None)); com_push(c, 1); } /* remaining arguments */ for (; i < NCH(n); i++) { ns++; ch=CHILD(n,i); REQ(ch, sliceop); if (NCH(ch) == 1) { /* right argument of ':' missing */ com_addoparg(c, LOAD_CONST, com_addconst(c, None)); com_push(c, 1); } else com_node(c, CHILD(ch,1)); } com_addoparg(c, BUILD_SLICE, ns); com_pop(c, 1 + (ns == 3)); } static void com_subscript(c, n) struct compiling *c; node *n; { node *ch; REQ(n, subscript); ch = CHILD(n,0); /* check for rubber index */ if (TYPE(ch) == DOT && TYPE(CHILD(n,1)) == DOT) { com_addoparg(c, LOAD_CONST, com_addconst(c, Py_Ellipsis)); com_push(c, 1); } else { /* check for slice */ if ((TYPE(ch) == COLON || NCH(n) > 1)) com_sliceobj(c, n); else { REQ(ch, test); com_node(c, ch); } } } static void com_subscriptlist(c, n, assigning) struct compiling *c; node *n; int assigning; { int i, op; REQ(n, subscriptlist); /* Check to make backward compatible slice behavior for '[i:j]' */ if (NCH(n) == 1) { node *sub = CHILD(n, 0); /* subscript */ /* Make it is a simple slice. Should have exactly one colon. */ if ((TYPE(CHILD(sub, 0)) == COLON || (NCH(sub) > 1 && TYPE(CHILD(sub, 1)) == COLON)) && (TYPE(CHILD(sub,NCH(sub)-1)) != sliceop)) { if (assigning == OP_APPLY) op = SLICE; else op = ((assigning == OP_ASSIGN) ? STORE_SLICE : DELETE_SLICE); com_slice(c, sub, op); if (op == STORE_SLICE) com_pop(c, 2); else if (op == DELETE_SLICE) com_pop(c, 1); return; } } /* Else normal subscriptlist. Compile each subscript. */ for (i = 0; i < NCH(n); i += 2) com_subscript(c, CHILD(n, i)); /* Put multiple subscripts into a tuple */ if (NCH(n) > 1) { i = (NCH(n)+1) / 2; com_addoparg(c, BUILD_TUPLE, i); com_pop(c, i-1); } if (assigning == OP_APPLY) { op = BINARY_SUBSCR; i = 1; } else if (assigning == OP_ASSIGN) { op = STORE_SUBSCR; i = 3; } else { op = DELETE_SUBSCR; i = 2; } com_addbyte(c, op); com_pop(c, i); } static void com_apply_trailer(c, n) struct compiling *c; node *n; { REQ(n, trailer); switch (TYPE(CHILD(n, 0))) { case LPAR: com_call_function(c, CHILD(n, 1)); break; case DOT: com_select_member(c, CHILD(n, 1)); break; case LSQB: com_subscriptlist(c, CHILD(n, 1), OP_APPLY); break; default: com_error(c, SystemError, "com_apply_trailer: unknown trailer type"); } } static void com_power(c, n) struct compiling *c; node *n; { int i; REQ(n, power); com_atom(c, CHILD(n, 0)); for (i = 1; i < NCH(n); i++) { if (TYPE(CHILD(n, i)) == DOUBLESTAR) { com_factor(c, CHILD(n, i+1)); com_addbyte(c, BINARY_POWER); com_pop(c, 1); break; } else com_apply_trailer(c, CHILD(n, i)); } } static void com_factor(c, n) struct compiling *c; node *n; { REQ(n, factor); if (TYPE(CHILD(n, 0)) == PLUS) { com_factor(c, CHILD(n, 1)); com_addbyte(c, UNARY_POSITIVE); } else if (TYPE(CHILD(n, 0)) == MINUS) { com_factor(c, CHILD(n, 1)); com_addbyte(c, UNARY_NEGATIVE); } else if (TYPE(CHILD(n, 0)) == TILDE) { com_factor(c, CHILD(n, 1)); com_addbyte(c, UNARY_INVERT); } else { com_power(c, CHILD(n, 0)); } } static void com_term(c, n) struct compiling *c; node *n; { int i; int op; REQ(n, term); com_factor(c, CHILD(n, 0)); for (i = 2; i < NCH(n); i += 2) { com_factor(c, CHILD(n, i)); switch (TYPE(CHILD(n, i-1))) { case STAR: op = BINARY_MULTIPLY; break; case SLASH: op = BINARY_DIVIDE; break; case PERCENT: op = BINARY_MODULO; break; default: com_error(c, SystemError, "com_term: operator not *, / or %"); op = 255; } com_addbyte(c, op); com_pop(c, 1); } } static void com_arith_expr(c, n) struct compiling *c; node *n; { int i; int op; REQ(n, arith_expr); com_term(c, CHILD(n, 0)); for (i = 2; i < NCH(n); i += 2) { com_term(c, CHILD(n, i)); switch (TYPE(CHILD(n, i-1))) { case PLUS: op = BINARY_ADD; break; case MINUS: op = BINARY_SUBTRACT; break; default: com_error(c, SystemError, "com_arith_expr: operator not + or -"); op = 255; } com_addbyte(c, op); com_pop(c, 1); } } static void com_shift_expr(c, n) struct compiling *c; node *n; { int i; int op; REQ(n, shift_expr); com_arith_expr(c, CHILD(n, 0)); for (i = 2; i < NCH(n); i += 2) { com_arith_expr(c, CHILD(n, i)); switch (TYPE(CHILD(n, i-1))) { case LEFTSHIFT: op = BINARY_LSHIFT; break; case RIGHTSHIFT: op = BINARY_RSHIFT; break; default: com_error(c, SystemError, "com_shift_expr: operator not << or >>"); op = 255; } com_addbyte(c, op); com_pop(c, 1); } } static void com_and_expr(c, n) struct compiling *c; node *n; { int i; int op; REQ(n, and_expr); com_shift_expr(c, CHILD(n, 0)); for (i = 2; i < NCH(n); i += 2) { com_shift_expr(c, CHILD(n, i)); if (TYPE(CHILD(n, i-1)) == AMPER) { op = BINARY_AND; } else { com_error(c, SystemError, "com_and_expr: operator not &"); op = 255; } com_addbyte(c, op); com_pop(c, 1); } } static void com_xor_expr(c, n) struct compiling *c; node *n; { int i; int op; REQ(n, xor_expr); com_and_expr(c, CHILD(n, 0)); for (i = 2; i < NCH(n); i += 2) { com_and_expr(c, CHILD(n, i)); if (TYPE(CHILD(n, i-1)) == CIRCUMFLEX) { op = BINARY_XOR; } else { com_error(c, SystemError, "com_xor_expr: operator not ^"); op = 255; } com_addbyte(c, op); com_pop(c, 1); } } static void com_expr(c, n) struct compiling *c; node *n; { int i; int op; REQ(n, expr); com_xor_expr(c, CHILD(n, 0)); for (i = 2; i < NCH(n); i += 2) { com_xor_expr(c, CHILD(n, i)); if (TYPE(CHILD(n, i-1)) == VBAR) { op = BINARY_OR; } else { com_error(c, SystemError, "com_expr: expr operator not |"); op = 255; } com_addbyte(c, op); com_pop(c, 1); } } static enum cmp_op cmp_type(n) node *n; { REQ(n, comp_op); /* comp_op: '<' | '>' | '=' | '>=' | '<=' | '<>' | '!=' | '==' | 'in' | 'not' 'in' | 'is' | 'is' not' */ if (NCH(n) == 1) { n = CHILD(n, 0); switch (TYPE(n)) { case LESS: return LT; case GREATER: return GT; case EQEQUAL: /* == */ case EQUAL: return EQ; case LESSEQUAL: return LE; case GREATEREQUAL: return GE; case NOTEQUAL: return NE; /* <> or != */ case NAME: if (strcmp(STR(n), "in") == 0) return IN; if (strcmp(STR(n), "is") == 0) return IS; } } else if (NCH(n) == 2) { switch (TYPE(CHILD(n, 0))) { case NAME: if (strcmp(STR(CHILD(n, 1)), "in") == 0) return NOT_IN; if (strcmp(STR(CHILD(n, 0)), "is") == 0) return IS_NOT; } } return BAD; } static void com_comparison(c, n) struct compiling *c; node *n; { int i; enum cmp_op op; int anchor; REQ(n, comparison); /* comparison: expr (comp_op expr)* */ com_expr(c, CHILD(n, 0)); if (NCH(n) == 1) return; /**************************************************************** The following code is generated for all but the last comparison in a chain: label: on stack: opcode: jump to: a a, b DUP_TOP a, b, b ROT_THREE b, a, b COMPARE_OP b, 0-or-1 JUMP_IF_FALSE L1 b, 1 POP_TOP b We are now ready to repeat this sequence for the next comparison in the chain. For the last we generate: b b, c COMPARE_OP 0-or-1 If there were any jumps to L1 (i.e., there was more than one comparison), we generate: 0-or-1 JUMP_FORWARD L2 L1: b, 0 ROT_TWO 0, b POP_TOP 0 L2: 0-or-1 ****************************************************************/ anchor = 0; for (i = 2; i < NCH(n); i += 2) { com_expr(c, CHILD(n, i)); if (i+2 < NCH(n)) { com_addbyte(c, DUP_TOP); com_push(c, 1); com_addbyte(c, ROT_THREE); } op = cmp_type(CHILD(n, i-1)); if (op == BAD) { com_error(c, SystemError, "com_comparison: unknown comparison op"); } com_addoparg(c, COMPARE_OP, op); com_pop(c, 1); if (i+2 < NCH(n)) { com_addfwref(c, JUMP_IF_FALSE, &anchor); com_addbyte(c, POP_TOP); com_pop(c, 1); } } if (anchor) { int anchor2 = 0; com_addfwref(c, JUMP_FORWARD, &anchor2); com_backpatch(c, anchor); com_addbyte(c, ROT_TWO); com_addbyte(c, POP_TOP); com_backpatch(c, anchor2); } } static void com_not_test(c, n) struct compiling *c; node *n; { REQ(n, not_test); /* 'not' not_test | comparison */ if (NCH(n) == 1) { com_comparison(c, CHILD(n, 0)); } else { com_not_test(c, CHILD(n, 1)); com_addbyte(c, UNARY_NOT); } } static void com_and_test(c, n) struct compiling *c; node *n; { int i; int anchor; REQ(n, and_test); /* not_test ('and' not_test)* */ anchor = 0; i = 0; for (;;) { com_not_test(c, CHILD(n, i)); if ((i += 2) >= NCH(n)) break; com_addfwref(c, JUMP_IF_FALSE, &anchor); com_addbyte(c, POP_TOP); com_pop(c, 1); } if (anchor) com_backpatch(c, anchor); } static void com_test(c, n) struct compiling *c; node *n; { REQ(n, test); /* and_test ('or' and_test)* | lambdef */ if (NCH(n) == 1 && TYPE(CHILD(n, 0)) == lambdef) { object *v; int i; int ndefs = com_argdefs(c, CHILD(n, 0)); v = (object *) icompile(CHILD(n, 0), c); if (v == NULL) { c->c_errors++; i = 255; } else { i = com_addconst(c, v); DECREF(v); } com_addoparg(c, LOAD_CONST, i); com_push(c, 1); com_addoparg(c, MAKE_FUNCTION, ndefs); com_pop(c, ndefs); } else { int anchor = 0; int i = 0; for (;;) { com_and_test(c, CHILD(n, i)); if ((i += 2) >= NCH(n)) break; com_addfwref(c, JUMP_IF_TRUE, &anchor); com_addbyte(c, POP_TOP); com_pop(c, 1); } if (anchor) com_backpatch(c, anchor); } } static void com_list(c, n, toplevel) struct compiling *c; node *n; int toplevel; /* If nonzero, *always* build a tuple */ { /* exprlist: expr (',' expr)* [',']; likewise for testlist */ if (NCH(n) == 1 && !toplevel) { com_node(c, CHILD(n, 0)); } else { int i; int len; len = (NCH(n) + 1) / 2; for (i = 0; i < NCH(n); i += 2) com_node(c, CHILD(n, i)); com_addoparg(c, BUILD_TUPLE, len); com_pop(c, len-1); } } /* Begin of assignment compilation */ static void com_assign_name PROTO((struct compiling *, node *, int)); static void com_assign PROTO((struct compiling *, node *, int)); static void com_assign_attr(c, n, assigning) struct compiling *c; node *n; int assigning; { com_addopname(c, assigning ? STORE_ATTR : DELETE_ATTR, n); com_pop(c, assigning ? 2 : 1); } static void com_assign_trailer(c, n, assigning) struct compiling *c; node *n; int assigning; { REQ(n, trailer); switch (TYPE(CHILD(n, 0))) { case LPAR: /* '(' [exprlist] ')' */ com_error(c, SyntaxError, "can't assign to function call"); break; case DOT: /* '.' NAME */ com_assign_attr(c, CHILD(n, 1), assigning); break; case LSQB: /* '[' subscriptlist ']' */ com_subscriptlist(c, CHILD(n, 1), assigning); break; default: com_error(c, SystemError, "unknown trailer type"); } } static void com_assign_tuple(c, n, assigning) struct compiling *c; node *n; int assigning; { int i; if (TYPE(n) != testlist) REQ(n, exprlist); if (assigning) { i = (NCH(n)+1)/2; com_addoparg(c, UNPACK_TUPLE, i); com_push(c, i-1); } for (i = 0; i < NCH(n); i += 2) com_assign(c, CHILD(n, i), assigning); } static void com_assign_list(c, n, assigning) struct compiling *c; node *n; int assigning; { int i; if (assigning) { i = (NCH(n)+1)/2; com_addoparg(c, UNPACK_LIST, i); com_push(c, i-1); } for (i = 0; i < NCH(n); i += 2) com_assign(c, CHILD(n, i), assigning); } static void com_assign_name(c, n, assigning) struct compiling *c; node *n; int assigning; { REQ(n, NAME); com_addopname(c, assigning ? STORE_NAME : DELETE_NAME, n); if (assigning) com_pop(c, 1); } static void com_assign(c, n, assigning) struct compiling *c; node *n; int assigning; { /* Loop to avoid trivial recursion */ for (;;) { switch (TYPE(n)) { case exprlist: case testlist: if (NCH(n) > 1) { com_assign_tuple(c, n, assigning); return; } n = CHILD(n, 0); break; case test: case and_test: case not_test: case comparison: case expr: case xor_expr: case and_expr: case shift_expr: case arith_expr: case term: case factor: if (NCH(n) > 1) { com_error(c, SyntaxError, "can't assign to operator"); return; } n = CHILD(n, 0); break; case power: /* atom trailer* ('**' power)* */ /* ('+'|'-'|'~') factor | atom trailer* */ if (TYPE(CHILD(n, 0)) != atom) { com_error(c, SyntaxError, "can't assign to operator"); return; } if (NCH(n) > 1) { /* trailer or exponent present */ int i; com_node(c, CHILD(n, 0)); for (i = 1; i+1 < NCH(n); i++) { if (TYPE(CHILD(n, i)) == DOUBLESTAR) { com_error(c, SyntaxError, "can't assign to operator"); return; } com_apply_trailer(c, CHILD(n, i)); } /* NB i is still alive */ com_assign_trailer(c, CHILD(n, i), assigning); return; } n = CHILD(n, 0); break; case atom: switch (TYPE(CHILD(n, 0))) { case LPAR: n = CHILD(n, 1); if (TYPE(n) == RPAR) { /* XXX Should allow () = () ??? */ com_error(c, SyntaxError, "can't assign to ()"); return; } break; case LSQB: n = CHILD(n, 1); if (TYPE(n) == RSQB) { com_error(c, SyntaxError, "can't assign to []"); return; } com_assign_list(c, n, assigning); return; case NAME: com_assign_name(c, CHILD(n, 0), assigning); return; default: com_error(c, SyntaxError, "can't assign to literal"); return; } break; case lambdef: com_error(c, SyntaxError, "can't assign to lambda"); return; default: /* XXX fprintf(stderr, "node type %d\n", TYPE(n)); */ com_error(c, SystemError, "com_assign: bad node"); return; } } } /* Forward */ static node *get_rawdocstring PROTO((node *)); static void com_expr_stmt(c, n) struct compiling *c; node *n; { REQ(n, expr_stmt); /* testlist ('=' testlist)* */ /* Forget it if we have just a doc string here */ if (NCH(n) == 1 && get_rawdocstring(n) != NULL) return; com_node(c, CHILD(n, NCH(n)-1)); if (NCH(n) == 1) { if (c->c_interactive) com_addbyte(c, PRINT_EXPR); else com_addbyte(c, POP_TOP); com_pop(c, 1); } else { int i; for (i = 0; i < NCH(n)-2; i+=2) { if (i+2 < NCH(n)-2) { com_addbyte(c, DUP_TOP); com_push(c, 1); } com_assign(c, CHILD(n, i), OP_ASSIGN); } } } static void com_print_stmt(c, n) struct compiling *c; node *n; { int i; REQ(n, print_stmt); /* 'print' (test ',')* [test] */ for (i = 1; i < NCH(n); i += 2) { com_node(c, CHILD(n, i)); com_addbyte(c, PRINT_ITEM); com_pop(c, 1); } if (TYPE(CHILD(n, NCH(n)-1)) != COMMA) com_addbyte(c, PRINT_NEWLINE); /* XXX Alternatively, LOAD_CONST '\n' and then PRINT_ITEM */ } static void com_return_stmt(c, n) struct compiling *c; node *n; { REQ(n, return_stmt); /* 'return' [testlist] */ if (!c->c_infunction) { com_error(c, SyntaxError, "'return' outside function"); } if (NCH(n) < 2) { com_addoparg(c, LOAD_CONST, com_addconst(c, None)); com_push(c, 1); } else com_node(c, CHILD(n, 1)); com_addbyte(c, RETURN_VALUE); com_pop(c, 1); } static void com_raise_stmt(c, n) struct compiling *c; node *n; { int i; REQ(n, raise_stmt); /* 'raise' test [',' test [',' test]] */ com_node(c, CHILD(n, 1)); if (NCH(n) > 3) { com_node(c, CHILD(n, 3)); if (NCH(n) > 5) com_node(c, CHILD(n, 5)); } i = NCH(n)/2; com_addoparg(c, RAISE_VARARGS, i); com_pop(c, i); } static void com_import_stmt(c, n) struct compiling *c; node *n; { int i; REQ(n, import_stmt); /* 'import' dotted_name (',' dotted_name)* | 'from' dotted_name 'import' ('*' | NAME (',' NAME)*) */ if (STR(CHILD(n, 0))[0] == 'f') { /* 'from' dotted_name 'import' ... */ REQ(CHILD(n, 1), dotted_name); com_addopname(c, IMPORT_NAME, CHILD(n, 1)); com_push(c, 1); for (i = 3; i < NCH(n); i += 2) com_addopname(c, IMPORT_FROM, CHILD(n, i)); com_addbyte(c, POP_TOP); com_pop(c, 1); } else { /* 'import' ... */ for (i = 1; i < NCH(n); i += 2) { REQ(CHILD(n, i), dotted_name); com_addopname(c, IMPORT_NAME, CHILD(n, i)); com_push(c, 1); com_addopname(c, STORE_NAME, CHILD(CHILD(n, i), 0)); com_pop(c, 1); } } } static void com_global_stmt(c, n) struct compiling *c; node *n; { int i; REQ(n, global_stmt); /* 'global' NAME (',' NAME)* */ for (i = 1; i < NCH(n); i += 2) { char *s = STR(CHILD(n, i)); #ifdef PRIVATE_NAME_MANGLING char buffer[256]; if (s != NULL && s[0] == '_' && s[1] == '_' && c->c_private != NULL && com_mangle(c, s, buffer, (int)sizeof(buffer))) s = buffer; #endif if (dictlookup(c->c_locals, s) != NULL) { com_error(c, SyntaxError, "name is local and global"); } else if (dictinsert(c->c_globals, s, None) != 0) c->c_errors++; } } static int com_newlocal_o(c, nameval) struct compiling *c; object *nameval; { int i; object *ival; if (getlistsize(c->c_varnames) != c->c_nlocals) { /* This is usually caused by an error on a previous call */ if (c->c_errors == 0) { com_error(c, SystemError, "mixed up var name/index"); } return 0; } ival = newintobject(i = c->c_nlocals++); if (ival == NULL) c->c_errors++; else if (mappinginsert(c->c_locals, nameval, ival) != 0) c->c_errors++; else if (addlistitem(c->c_varnames, nameval) != 0) c->c_errors++; XDECREF(ival); return i; } static int com_addlocal_o(c, nameval) struct compiling *c; object *nameval; { object *ival = mappinglookup(c->c_locals, nameval); if (ival != NULL) return getintvalue(ival); return com_newlocal_o(c, nameval); } static int com_newlocal(c, name) struct compiling *c; char *name; { object *nameval = newstringobject(name); int i; if (nameval == NULL) { c->c_errors++; return 0; } i = com_newlocal_o(c, nameval); DECREF(nameval); return i; } #ifdef SUPPORT_OBSOLETE_ACCESS #define strequ(a, b) (strcmp((a), (b)) == 0) static void com_access_stmt(c, n) struct compiling *c; node *n; { int i, j, k, mode, imode; object *vmode; REQ(n, access_stmt); /* 'access' NAME (',' NAME)* ':' accesstype (',' accesstype)* accesstype: NAME+ */ /* Find where the colon is */ i = 1; while (TYPE(CHILD(n,i-1)) != COLON) i += 1; /* Calculate the mode mask */ mode = 0; for (j = i; j < NCH(n); j += 2) { int r = 0, w = 0, p = 0; for (k = 0; k < NCH(CHILD(n,j)); k++) { if (strequ(STR(CHILD(CHILD(n,j),k)), "public")) p = 0; else if (strequ(STR(CHILD(CHILD(n,j),k)), "protected")) p = 1; else if (strequ(STR(CHILD(CHILD(n,j),k)), "private")) p = 2; else if (strequ(STR(CHILD(CHILD(n,j),k)), "read")) r = 1; else if (strequ(STR(CHILD(CHILD(n,j),k)), "write")) w = 1; else /* XXX should make this an exception */ fprintf(stderr, "bad access type %s\n", STR(CHILD(CHILD(n,j),k))); } if (r == 0 && w == 0) r = w = 1; if (p == 0) { if (r == 1) mode |= AC_R_PUBLIC; if (w == 1) mode |= AC_W_PUBLIC; } else if (p == 1) { if (r == 1) mode |= AC_R_PROTECTED; if (w == 1) mode |= AC_W_PROTECTED; } else { if (r == 1) mode |= AC_R_PRIVATE; if (w == 1) mode |= AC_W_PRIVATE; } } vmode = newintobject((long)mode); imode = com_addconst(c, vmode); XDECREF(vmode); for (i = 1; TYPE(CHILD(n,i-1)) != COLON; i+=2) { com_addoparg(c, LOAD_CONST, imode); com_addopname(c, ACCESS_MODE, CHILD(n, i)); } } #endif static void com_exec_stmt(c, n) struct compiling *c; node *n; { REQ(n, exec_stmt); /* exec_stmt: 'exec' expr ['in' expr [',' expr]] */ com_node(c, CHILD(n, 1)); if (NCH(n) >= 4) com_node(c, CHILD(n, 3)); else { com_addoparg(c, LOAD_CONST, com_addconst(c, None)); com_push(c, 1); } if (NCH(n) >= 6) com_node(c, CHILD(n, 5)); else { com_addbyte(c, DUP_TOP); com_push(c, 1); } com_addbyte(c, EXEC_STMT); com_pop(c, 3); } static void com_if_stmt(c, n) struct compiling *c; node *n; { int i; int anchor = 0; REQ(n, if_stmt); /*'if' test ':' suite ('elif' test ':' suite)* ['else' ':' suite] */ for (i = 0; i+3 < NCH(n); i+=4) { int a = 0; node *ch = CHILD(n, i+1); if (i > 0) com_addoparg(c, SET_LINENO, ch->n_lineno); com_node(c, CHILD(n, i+1)); com_addfwref(c, JUMP_IF_FALSE, &a); com_addbyte(c, POP_TOP); com_pop(c, 1); com_node(c, CHILD(n, i+3)); com_addfwref(c, JUMP_FORWARD, &anchor); com_backpatch(c, a); /* We jump here with an extra entry which we now pop */ com_addbyte(c, POP_TOP); } if (i+2 < NCH(n)) com_node(c, CHILD(n, i+2)); com_backpatch(c, anchor); } static void com_while_stmt(c, n) struct compiling *c; node *n; { int break_anchor = 0; int anchor = 0; int save_begin = c->c_begin; REQ(n, while_stmt); /* 'while' test ':' suite ['else' ':' suite] */ com_addfwref(c, SETUP_LOOP, &break_anchor); block_push(c, SETUP_LOOP); c->c_begin = c->c_nexti; com_addoparg(c, SET_LINENO, n->n_lineno); com_node(c, CHILD(n, 1)); com_addfwref(c, JUMP_IF_FALSE, &anchor); com_addbyte(c, POP_TOP); com_pop(c, 1); c->c_loops++; com_node(c, CHILD(n, 3)); c->c_loops--; com_addoparg(c, JUMP_ABSOLUTE, c->c_begin); c->c_begin = save_begin; com_backpatch(c, anchor); /* We jump here with one entry more on the stack */ com_addbyte(c, POP_TOP); com_addbyte(c, POP_BLOCK); block_pop(c, SETUP_LOOP); if (NCH(n) > 4) com_node(c, CHILD(n, 6)); com_backpatch(c, break_anchor); } static void com_for_stmt(c, n) struct compiling *c; node *n; { object *v; int break_anchor = 0; int anchor = 0; int save_begin = c->c_begin; REQ(n, for_stmt); /* 'for' exprlist 'in' exprlist ':' suite ['else' ':' suite] */ com_addfwref(c, SETUP_LOOP, &break_anchor); block_push(c, SETUP_LOOP); com_node(c, CHILD(n, 3)); v = newintobject(0L); if (v == NULL) c->c_errors++; com_addoparg(c, LOAD_CONST, com_addconst(c, v)); com_push(c, 1); XDECREF(v); c->c_begin = c->c_nexti; com_addoparg(c, SET_LINENO, n->n_lineno); com_addfwref(c, FOR_LOOP, &anchor); com_push(c, 1); com_assign(c, CHILD(n, 1), OP_ASSIGN); c->c_loops++; com_node(c, CHILD(n, 5)); c->c_loops--; com_addoparg(c, JUMP_ABSOLUTE, c->c_begin); c->c_begin = save_begin; com_backpatch(c, anchor); com_pop(c, 2); /* FOR_LOOP has popped these */ com_addbyte(c, POP_BLOCK); block_pop(c, SETUP_LOOP); if (NCH(n) > 8) com_node(c, CHILD(n, 8)); com_backpatch(c, break_anchor); } /* Code generated for "try: S finally: Sf" is as follows: SETUP_FINALLY L POP_BLOCK LOAD_CONST L: 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, and pops the value stack until its level is the same as indicated on the block stack. (The label is ignored.) END_FINALLY: Pops a variable number of entries from the *value* stack and re-raises the exception they specify. The number of entries popped depends on the (pseudo) exception type. The block stack is unwound when an exception is raised: when a SETUP_FINALLY entry is found, the exception is pushed onto the value stack (and the exception condition is cleared), and the interpreter jumps to the label gotten from the block stack. Code generated for "try: S except E1, V1: S1 except E2, 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_EXCEPT L1 [] [] POP_BLOCK [] JUMP_FORWARD L0 [tb, val, exc] L1: DUP ) [tb, val, exc, exc] ) [tb, val, exc, exc, E1] COMPARE_OP EXC_MATCH ) only if E1 [tb, val, exc, 1-or-0] JUMP_IF_FALSE L2 ) [tb, val, exc, 1] POP ) [tb, val, exc] POP [tb, val] (or POP if no V1) [tb] POP [] JUMP_FORWARD L0 [tb, val, exc, 0] L2: POP [tb, val, exc] DUP .............................etc....................... [tb, val, exc, 0] Ln+1: POP [tb, val, exc] END_FINALLY # re-raise exception [] L0: Of course, parts are not generated if Vi or Ei is not present. */ static void com_try_except(c, n) struct compiling *c; node *n; { int except_anchor = 0; int end_anchor = 0; int else_anchor = 0; int i; node *ch; com_addfwref(c, SETUP_EXCEPT, &except_anchor); block_push(c, SETUP_EXCEPT); com_node(c, CHILD(n, 2)); com_addbyte(c, POP_BLOCK); block_pop(c, SETUP_EXCEPT); com_addfwref(c, JUMP_FORWARD, &else_anchor); com_backpatch(c, except_anchor); for (i = 3; i < NCH(n) && TYPE(ch = CHILD(n, i)) == except_clause; i += 3) { /* except_clause: 'except' [expr [',' var]] */ if (except_anchor == 0) { com_error(c, SyntaxError, "default 'except:' must be last"); break; } except_anchor = 0; com_push(c, 3); /* tb, val, exc pushed by exception */ com_addoparg(c, SET_LINENO, ch->n_lineno); if (NCH(ch) > 1) { com_addbyte(c, DUP_TOP); com_push(c, 1); com_node(c, CHILD(ch, 1)); com_addoparg(c, COMPARE_OP, EXC_MATCH); com_pop(c, 1); com_addfwref(c, JUMP_IF_FALSE, &except_anchor); com_addbyte(c, POP_TOP); com_pop(c, 1); } com_addbyte(c, POP_TOP); com_pop(c, 1); if (NCH(ch) > 3) com_assign(c, CHILD(ch, 3), OP_ASSIGN); else { com_addbyte(c, POP_TOP); com_pop(c, 1); } com_addbyte(c, POP_TOP); com_pop(c, 1); com_node(c, CHILD(n, i+2)); com_addfwref(c, JUMP_FORWARD, &end_anchor); if (except_anchor) { com_backpatch(c, except_anchor); /* We come in with [tb, val, exc, 0] on the stack; one pop and it's the same as expected at the start of the loop */ com_addbyte(c, POP_TOP); } } /* We actually come in here with [tb, val, exc] but the END_FINALLY will zap those and jump around. The c_stacklevel does not reflect them so we need not pop anything. */ com_addbyte(c, END_FINALLY); com_backpatch(c, else_anchor); if (i < NCH(n)) com_node(c, CHILD(n, i+2)); com_backpatch(c, end_anchor); } static void com_try_finally(c, n) struct compiling *c; node *n; { int finally_anchor = 0; node *ch; com_addfwref(c, SETUP_FINALLY, &finally_anchor); block_push(c, SETUP_FINALLY); com_node(c, CHILD(n, 2)); com_addbyte(c, POP_BLOCK); block_pop(c, SETUP_FINALLY); block_push(c, END_FINALLY); com_addoparg(c, LOAD_CONST, com_addconst(c, None)); /* While the generated code pushes only one item, the try-finally handling can enter here with up to three items. OK, here are the details: 3 for an exception, 2 for RETURN, 1 for BREAK. */ com_push(c, 3); com_backpatch(c, finally_anchor); ch = CHILD(n, NCH(n)-1); com_addoparg(c, SET_LINENO, ch->n_lineno); com_node(c, ch); com_addbyte(c, END_FINALLY); block_pop(c, END_FINALLY); com_pop(c, 3); /* Matches the com_push above */ } static void com_try_stmt(c, n) struct compiling *c; node *n; { REQ(n, try_stmt); /* 'try' ':' suite (except_clause ':' suite)+ ['else' ':' suite] | 'try' ':' suite 'finally' ':' suite */ if (TYPE(CHILD(n, 3)) != except_clause) com_try_finally(c, n); else com_try_except(c, n); } static node * get_rawdocstring(n) node *n; { int i; /* Label to avoid tail recursion */ next: switch (TYPE(n)) { case suite: if (NCH(n) == 1) { n = CHILD(n, 0); goto next; } /* Fall through */ case file_input: for (i = 0; i < NCH(n); i++) { node *ch = CHILD(n, i); if (TYPE(ch) == stmt) { n = ch; goto next; } } break; case stmt: case simple_stmt: case small_stmt: n = CHILD(n, 0); goto next; case expr_stmt: case testlist: case test: case and_test: case not_test: case comparison: case expr: case xor_expr: case and_expr: case shift_expr: case arith_expr: case term: case factor: case power: if (NCH(n) == 1) { n = CHILD(n, 0); goto next; } break; case atom: if (TYPE(CHILD(n, 0)) == STRING) return n; break; } return NULL; } static object * get_docstring(n) node *n; { n = get_rawdocstring(n); if (n == NULL) return NULL; return parsestrplus(n); } static void com_suite(c, n) struct compiling *c; node *n; { REQ(n, suite); /* simple_stmt | NEWLINE INDENT NEWLINE* (stmt NEWLINE*)+ DEDENT */ if (NCH(n) == 1) { com_node(c, CHILD(n, 0)); } else { int i; for (i = 0; i < NCH(n); i++) { node *ch = CHILD(n, i); if (TYPE(ch) == stmt) com_node(c, ch); } } } /* ARGSUSED */ static void com_continue_stmt(c, n) struct compiling *c; node *n; /* Not used, but passed for consistency */ { int i = c->c_nblocks; if (i-- > 0 && c->c_block[i] == SETUP_LOOP) { com_addoparg(c, JUMP_ABSOLUTE, c->c_begin); } else { com_error(c, SyntaxError, "'continue' not properly in loop"); } /* XXX Could allow it inside a 'finally' clause XXX if we could pop the exception still on the stack */ } static int com_argdefs(c, n) struct compiling *c; node *n; { int i, nch, nargs, ndefs; if (TYPE(n) == lambdef) { /* lambdef: 'lambda' [varargslist] ':' test */ n = CHILD(n, 1); } else { REQ(n, funcdef); /* funcdef: 'def' NAME parameters ... */ n = CHILD(n, 2); REQ(n, parameters); /* parameters: '(' [varargslist] ')' */ n = CHILD(n, 1); } if (TYPE(n) != varargslist) return 0; /* varargslist: (fpdef ['=' test] ',')* '*' ....... | fpdef ['=' test] (',' fpdef ['=' test])* [','] */ nch = NCH(n); nargs = 0; ndefs = 0; for (i = 0; i < nch; i++) { int t; if (TYPE(CHILD(n, i)) == STAR || TYPE(CHILD(n, i)) == DOUBLESTAR) break; nargs++; i++; if (i >= nch) t = RPAR; /* Anything except EQUAL or COMMA */ else t = TYPE(CHILD(n, i)); if (t == EQUAL) { i++; ndefs++; com_node(c, CHILD(n, i)); i++; if (i >= nch) break; t = TYPE(CHILD(n, i)); } else { /* Treat "(a=1, b)" as "(a=1, b=None)" */ if (ndefs) { com_addoparg(c, LOAD_CONST, com_addconst(c, None)); com_push(c, 1); ndefs++; } } if (t != COMMA) break; } return ndefs; } static void com_funcdef(c, n) struct compiling *c; node *n; { object *v; REQ(n, funcdef); /* funcdef: 'def' NAME parameters ':' suite */ v = (object *)icompile(n, c); if (v == NULL) c->c_errors++; else { int i = com_addconst(c, v); int ndefs = com_argdefs(c, n); com_addoparg(c, LOAD_CONST, i); com_push(c, 1); com_addoparg(c, MAKE_FUNCTION, ndefs); com_pop(c, ndefs); com_addopname(c, STORE_NAME, CHILD(n, 1)); com_pop(c, 1); DECREF(v); } } static void com_bases(c, n) struct compiling *c; node *n; { int i; REQ(n, testlist); /* testlist: test (',' test)* [','] */ for (i = 0; i < NCH(n); i += 2) com_node(c, CHILD(n, i)); i = (NCH(n)+1) / 2; com_addoparg(c, BUILD_TUPLE, i); com_pop(c, i-1); } static void com_classdef(c, n) struct compiling *c; node *n; { int i; object *v; REQ(n, classdef); /* classdef: class NAME ['(' testlist ')'] ':' suite */ if ((v = newstringobject(STR(CHILD(n, 1)))) == NULL) { c->c_errors++; return; } /* Push the class name on the stack */ i = com_addconst(c, v); com_addoparg(c, LOAD_CONST, i); com_push(c, 1); DECREF(v); /* Push the tuple of base classes on the stack */ if (TYPE(CHILD(n, 2)) != LPAR) { com_addoparg(c, BUILD_TUPLE, 0); com_push(c, 1); } else com_bases(c, CHILD(n, 3)); v = (object *)icompile(n, c); if (v == NULL) c->c_errors++; else { i = com_addconst(c, v); com_addoparg(c, LOAD_CONST, i); com_push(c, 1); com_addoparg(c, MAKE_FUNCTION, 0); com_addoparg(c, CALL_FUNCTION, 0); com_addbyte(c, BUILD_CLASS); com_pop(c, 2); com_addopname(c, STORE_NAME, CHILD(n, 1)); DECREF(v); } } static void com_node(c, n) struct compiling *c; node *n; { switch (TYPE(n)) { /* Definition nodes */ case funcdef: com_funcdef(c, n); break; case classdef: com_classdef(c, n); break; /* Trivial parse tree nodes */ case stmt: case small_stmt: case flow_stmt: com_node(c, CHILD(n, 0)); break; case simple_stmt: /* small_stmt (';' small_stmt)* [';'] NEWLINE */ com_addoparg(c, SET_LINENO, n->n_lineno); { int i; for (i = 0; i < NCH(n)-1; i += 2) com_node(c, CHILD(n, i)); } break; case compound_stmt: com_addoparg(c, SET_LINENO, n->n_lineno); com_node(c, CHILD(n, 0)); break; /* Statement nodes */ case expr_stmt: com_expr_stmt(c, n); break; case print_stmt: com_print_stmt(c, n); break; case del_stmt: /* 'del' exprlist */ com_assign(c, CHILD(n, 1), OP_DELETE); break; case pass_stmt: break; case break_stmt: if (c->c_loops == 0) { com_error(c, SyntaxError, "'break' outside loop"); } com_addbyte(c, BREAK_LOOP); break; case continue_stmt: com_continue_stmt(c, n); break; case return_stmt: com_return_stmt(c, n); break; case raise_stmt: com_raise_stmt(c, n); break; case import_stmt: com_import_stmt(c, n); break; case global_stmt: com_global_stmt(c, n); break; #ifdef SUPPORT_OBSOLETE_ACCESS case access_stmt: com_access_stmt(c, n); break; #endif case exec_stmt: com_exec_stmt(c, n); break; case if_stmt: com_if_stmt(c, n); break; case while_stmt: com_while_stmt(c, n); break; case for_stmt: com_for_stmt(c, n); break; case try_stmt: com_try_stmt(c, n); break; case suite: com_suite(c, n); break; /* Expression nodes */ case testlist: com_list(c, n, 0); break; case test: com_test(c, n); break; case and_test: com_and_test(c, n); break; case not_test: com_not_test(c, n); break; case comparison: com_comparison(c, n); break; case exprlist: com_list(c, n, 0); break; case expr: com_expr(c, n); break; case xor_expr: com_xor_expr(c, n); break; case and_expr: com_and_expr(c, n); break; case shift_expr: com_shift_expr(c, n); break; case arith_expr: com_arith_expr(c, n); break; case term: com_term(c, n); break; case factor: com_factor(c, n); break; case power: com_power(c, n); break; case atom: com_atom(c, n); break; default: /* XXX fprintf(stderr, "node type %d\n", TYPE(n)); */ com_error(c, SystemError, "com_node: unexpected node type"); } } static void com_fplist PROTO((struct compiling *, node *)); static void com_fpdef(c, n) struct compiling *c; node *n; { REQ(n, fpdef); /* fpdef: NAME | '(' fplist ')' */ if (TYPE(CHILD(n, 0)) == LPAR) com_fplist(c, CHILD(n, 1)); else { com_addoparg(c, STORE_FAST, com_newlocal(c, STR(CHILD(n, 0)))); com_pop(c, 1); } } static void com_fplist(c, n) struct compiling *c; node *n; { REQ(n, fplist); /* fplist: fpdef (',' fpdef)* [','] */ if (NCH(n) == 1) { com_fpdef(c, CHILD(n, 0)); } else { int i = (NCH(n)+1)/2; com_addoparg(c, UNPACK_TUPLE, i); com_push(c, i-1); for (i = 0; i < NCH(n); i += 2) com_fpdef(c, CHILD(n, i)); } } static void com_arglist(c, n) struct compiling *c; node *n; { int nch, i; int complex = 0; REQ(n, varargslist); /* varargslist: (fpdef ['=' test] ',')* (fpdef ['=' test] | '*' .....) */ nch = NCH(n); /* Enter all arguments in table of locals */ for (i = 0; i < nch; i++) { node *ch = CHILD(n, i); node *fp; char *name; if (TYPE(ch) == STAR || TYPE(ch) == DOUBLESTAR) break; REQ(ch, fpdef); /* fpdef: NAME | '(' fplist ')' */ fp = CHILD(ch, 0); if (TYPE(fp) == NAME) name = STR(fp); else { name = ""; complex = 1; } com_newlocal(c, name); c->c_argcount++; if (++i >= nch) break; ch = CHILD(n, i); if (TYPE(ch) == EQUAL) i += 2; else REQ(ch, COMMA); } /* Handle *arguments */ if (i < nch) { node *ch; ch = CHILD(n, i); if (TYPE(ch) != DOUBLESTAR) { REQ(ch, STAR); ch = CHILD(n, i+1); if (TYPE(ch) == NAME) { c->c_flags |= CO_VARARGS; i += 3; com_newlocal(c, STR(ch)); } } } /* Handle **keywords */ if (i < nch) { node *ch; ch = CHILD(n, i); if (TYPE(ch) != DOUBLESTAR) { REQ(ch, STAR); ch = CHILD(n, i+1); REQ(ch, STAR); ch = CHILD(n, i+2); } else ch = CHILD(n, i+1); REQ(ch, NAME); c->c_flags |= CO_VARKEYWORDS; com_newlocal(c, STR(ch)); } if (complex) { /* Generate code for complex arguments only after having counted the simple arguments */ int ilocal = 0; for (i = 0; i < nch; i++) { node *ch = CHILD(n, i); node *fp; if (TYPE(ch) == STAR || TYPE(ch) == DOUBLESTAR) break; REQ(ch, fpdef); /* fpdef: NAME | '(' fplist ')' */ fp = CHILD(ch, 0); if (TYPE(fp) != NAME) { com_addoparg(c, LOAD_FAST, ilocal); com_push(c, 1); com_fpdef(c, ch); } ilocal++; if (++i >= nch) break; ch = CHILD(n, i); if (TYPE(ch) == EQUAL) i += 2; else REQ(ch, COMMA); } } } static void com_file_input(c, n) struct compiling *c; node *n; { int i; object *doc; REQ(n, file_input); /* (NEWLINE | stmt)* ENDMARKER */ doc = get_docstring(n); if (doc != NULL) { int i = com_addconst(c, doc); DECREF(doc); com_addoparg(c, LOAD_CONST, i); com_push(c, 1); com_addopnamestr(c, STORE_NAME, "__doc__"); com_pop(c, 1); } for (i = 0; i < NCH(n); i++) { node *ch = CHILD(n, i); if (TYPE(ch) != ENDMARKER && TYPE(ch) != NEWLINE) com_node(c, ch); } } /* Top-level compile-node interface */ static void compile_funcdef(c, n) struct compiling *c; node *n; { object *doc; node *ch; REQ(n, funcdef); /* funcdef: 'def' NAME parameters ':' suite */ c->c_name = STR(CHILD(n, 1)); doc = get_docstring(CHILD(n, 4)); if (doc != NULL) { (void) com_addconst(c, doc); DECREF(doc); } else (void) com_addconst(c, None); /* No docstring */ ch = CHILD(n, 2); /* parameters: '(' [varargslist] ')' */ ch = CHILD(ch, 1); /* ')' | varargslist */ if (TYPE(ch) == varargslist) com_arglist(c, ch); c->c_infunction = 1; com_node(c, CHILD(n, 4)); c->c_infunction = 0; com_addoparg(c, LOAD_CONST, com_addconst(c, None)); com_push(c, 1); com_addbyte(c, RETURN_VALUE); com_pop(c, 1); } static void compile_lambdef(c, n) struct compiling *c; node *n; { node *ch; REQ(n, lambdef); /* lambdef: 'lambda' [varargslist] ':' test */ c->c_name = ""; ch = CHILD(n, 1); (void) com_addconst(c, None); /* No docstring */ if (TYPE(ch) == varargslist) { com_arglist(c, ch); ch = CHILD(n, 3); } else ch = CHILD(n, 2); com_node(c, ch); com_addbyte(c, RETURN_VALUE); com_pop(c, 1); } static void compile_classdef(c, n) struct compiling *c; node *n; { node *ch; object *doc; REQ(n, classdef); /* classdef: 'class' NAME ['(' testlist ')'] ':' suite */ c->c_name = STR(CHILD(n, 1)); #ifdef PRIVATE_NAME_MANGLING c->c_private = c->c_name; #endif ch = CHILD(n, NCH(n)-1); /* The suite */ doc = get_docstring(ch); if (doc != NULL) { int i = com_addconst(c, doc); DECREF(doc); com_addoparg(c, LOAD_CONST, i); com_push(c, 1); com_addopnamestr(c, STORE_NAME, "__doc__"); com_pop(c, 1); } else (void) com_addconst(c, None); com_node(c, ch); com_addbyte(c, LOAD_LOCALS); com_push(c, 1); com_addbyte(c, RETURN_VALUE); com_pop(c, 1); } static void compile_node(c, n) struct compiling *c; node *n; { com_addoparg(c, SET_LINENO, n->n_lineno); switch (TYPE(n)) { case single_input: /* One interactive command */ /* NEWLINE | simple_stmt | compound_stmt NEWLINE */ c->c_interactive++; n = CHILD(n, 0); if (TYPE(n) != NEWLINE) com_node(c, n); com_addoparg(c, LOAD_CONST, com_addconst(c, None)); com_push(c, 1); com_addbyte(c, RETURN_VALUE); com_pop(c, 1); c->c_interactive--; break; case file_input: /* A whole file, or built-in function exec() */ com_file_input(c, n); com_addoparg(c, LOAD_CONST, com_addconst(c, None)); com_push(c, 1); com_addbyte(c, RETURN_VALUE); com_pop(c, 1); break; case eval_input: /* Built-in function input() */ com_node(c, CHILD(n, 0)); com_addbyte(c, RETURN_VALUE); com_pop(c, 1); break; case lambdef: /* anonymous function definition */ compile_lambdef(c, n); break; case funcdef: /* A function definition */ compile_funcdef(c, n); break; case classdef: /* A class definition */ compile_classdef(c, n); break; default: /* XXX fprintf(stderr, "node type %d\n", TYPE(n)); */ com_error(c, SystemError, "compile_node: unexpected node type"); } } /* Optimization for local variables in functions (and *only* functions). This replaces all LOAD_NAME, STORE_NAME and DELETE_NAME instructions that refer to local variables with LOAD_FAST etc. The latter instructions are much faster because they don't need to look up the variable name in a dictionary. To find all local variables, we check all STORE_NAME, IMPORT_FROM and DELETE_NAME instructions. This yields all local variables, function definitions, class definitions and import statements. Argument names have already been entered into the list by the special processing for the argument list. All remaining LOAD_NAME instructions must refer to non-local (global or builtin) variables, so are replaced by LOAD_GLOBAL. There are two problems: 'from foo import *' and 'exec' may introduce local variables that we can't know while compiling. If this is the case, we can still optimize bona fide locals (since those statements will be surrounded by fast_2_locals() and locals_2_fast()), but we can't change LOAD_NAME to LOAD_GLOBAL. NB: this modifies the string object c->c_code! */ static void optimize(c) struct compiling *c; { unsigned char *next_instr, *cur_instr; int opcode; int oparg = 0; object *name; object *error_type, *error_value, *error_traceback; #define NEXTOP() (*next_instr++) #define NEXTARG() (next_instr += 2, (next_instr[-1]<<8) + next_instr[-2]) #define GETITEM(v, i) (getlistitem((v), (i))) #define GETNAMEOBJ(i) (GETITEM(c->c_names, (i))) err_fetch(&error_type, &error_value, &error_traceback); c->c_flags |= CO_OPTIMIZED; next_instr = (unsigned char *) getstringvalue(c->c_code); for (;;) { opcode = NEXTOP(); if (opcode == STOP_CODE) break; if (HAS_ARG(opcode)) oparg = NEXTARG(); switch (opcode) { case STORE_NAME: case DELETE_NAME: case IMPORT_FROM: com_addlocal_o(c, GETNAMEOBJ(oparg)); break; case EXEC_STMT: c->c_flags &= ~CO_OPTIMIZED; break; } } if (dictlookup(c->c_locals, "*") != NULL) c->c_flags &= ~CO_OPTIMIZED; next_instr = (unsigned char *) getstringvalue(c->c_code); for (;;) { cur_instr = next_instr; opcode = NEXTOP(); if (opcode == STOP_CODE) break; if (HAS_ARG(opcode)) oparg = NEXTARG(); if (opcode == LOAD_NAME || opcode == STORE_NAME || opcode == DELETE_NAME) { object *v; int i; name = GETNAMEOBJ(oparg); v = dict2lookup(c->c_locals, name); if (v == NULL) { err_clear(); if (opcode == LOAD_NAME && (c->c_flags&CO_OPTIMIZED)) cur_instr[0] = LOAD_GLOBAL; continue; } i = getintvalue(v); switch (opcode) { case LOAD_NAME: cur_instr[0] = LOAD_FAST; break; case STORE_NAME: cur_instr[0] = STORE_FAST; break; case DELETE_NAME: cur_instr[0] = DELETE_FAST; break; } cur_instr[1] = i & 0xff; cur_instr[2] = (i>>8) & 0xff; } } if (c->c_errors == 0) err_restore(error_type, error_value, error_traceback); } codeobject * compile(n, filename) node *n; char *filename; { return jcompile(n, filename, NULL); } static codeobject * icompile(n, base) node *n; struct compiling *base; { return jcompile(n, base->c_filename, base); } static codeobject * jcompile(n, filename, base) node *n; char *filename; struct compiling *base; { struct compiling sc; codeobject *co; if (!com_init(&sc, filename)) return NULL; #ifdef PRIVATE_NAME_MANGLING if (base) sc.c_private = base->c_private; else sc.c_private = NULL; #endif compile_node(&sc, n); com_done(&sc); if ((TYPE(n) == funcdef || TYPE(n) == lambdef) && sc.c_errors == 0) { optimize(&sc); sc.c_flags |= CO_NEWLOCALS; } else if (TYPE(n) == classdef) sc.c_flags |= CO_NEWLOCALS; co = NULL; if (sc.c_errors == 0) { object *consts, *names, *varnames, *filename, *name; consts = listtuple(sc.c_consts); names = listtuple(sc.c_names); varnames = listtuple(sc.c_varnames); filename = newstringobject(sc.c_filename); name = newstringobject(sc.c_name); if (!err_occurred()) co = newcodeobject(sc.c_argcount, sc.c_nlocals, sc.c_maxstacklevel, sc.c_flags, sc.c_code, consts, names, varnames, filename, name); XDECREF(consts); XDECREF(names); XDECREF(varnames); XDECREF(filename); XDECREF(name); } com_free(&sc); return co; }