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+/***********************************************************
+Copyright 1991 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 not be used in advertising or publicity pertaining to
+distribution of the software without specific, written prior permission.
+
+STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
+THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM 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 Compute maximum needed stack sizes while compiling
+ XXX Generate simple jump for break/return outside 'try...finally'
+ XXX Include function name in code (and module names?)
+*/
+
+#include "allobjects.h"
+
+#include "node.h"
+#include "token.h"
+#include "graminit.h"
+#include "compile.h"
+#include "opcode.h"
+#include "structmember.h"
+
+#include <ctype.h>
+
+#define OFF(x) offsetof(codeobject, x)
+
+static struct memberlist code_memberlist[] = {
+ {"co_code", T_OBJECT, OFF(co_code)},
+ {"co_consts", T_OBJECT, OFF(co_consts)},
+ {"co_names", T_OBJECT, OFF(co_names)},
+ {"co_filename", T_OBJECT, OFF(co_filename)},
+ {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);
+ DEL(co);
+}
+
+typeobject Codetype = {
+ OB_HEAD_INIT(&Typetype)
+ 0,
+ "code",
+ sizeof(codeobject),
+ 0,
+ code_dealloc, /*tp_dealloc*/
+ 0, /*tp_print*/
+ code_getattr, /*tp_getattr*/
+ 0, /*tp_setattr*/
+ 0, /*tp_compare*/
+ 0, /*tp_repr*/
+ 0, /*tp_as_number*/
+ 0, /*tp_as_sequence*/
+ 0, /*tp_as_mapping*/
+};
+
+static codeobject *newcodeobject PROTO((object *, object *, object *, char *));
+
+static codeobject *
+newcodeobject(code, consts, names, filename)
+ object *code;
+ object *consts;
+ object *names;
+ char *filename;
+{
+ codeobject *co;
+ int i;
+ /* Check argument types */
+ if (code == NULL || !is_stringobject(code) ||
+ consts == NULL || !is_listobject(consts) ||
+ names == NULL || !is_listobject(names)) {
+ err_badcall();
+ return NULL;
+ }
+ /* Make sure the list of names contains only strings */
+ for (i = getlistsize(names); --i >= 0; ) {
+ object *v = getlistitem(names, i);
+ if (v == NULL || !is_stringobject(v)) {
+ err_badcall();
+ return NULL;
+ }
+ }
+ co = NEWOBJ(codeobject, &Codetype);
+ if (co != NULL) {
+ INCREF(code);
+ co->co_code = (stringobject *)code;
+ INCREF(consts);
+ co->co_consts = consts;
+ INCREF(names);
+ co->co_names = names;
+ if ((co->co_filename = newstringobject(filename)) == NULL) {
+ DECREF(co);
+ co = NULL;
+ }
+ }
+ 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) */
+ int c_nexti; /* index into c_code */
+ int c_errors; /* counts errors occurred */
+ int c_infunction; /* set when compiling a function */
+ int c_loops; /* counts nested loops */
+ char *c_filename; /* filename of current node */
+};
+
+/* Prototypes */
+static int com_init PROTO((struct compiling *, char *));
+static void com_free PROTO((struct compiling *));
+static void com_done PROTO((struct compiling *));
+static void com_node 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 int
+com_init(c, filename)
+ struct compiling *c;
+ char *filename;
+{
+ if ((c->c_code = newsizedstringobject((char *)NULL, 0)) == NULL)
+ goto fail_3;
+ if ((c->c_consts = newlistobject(0)) == NULL)
+ goto fail_2;
+ if ((c->c_names = newlistobject(0)) == NULL)
+ goto fail_1;
+ c->c_nexti = 0;
+ c->c_errors = 0;
+ c->c_infunction = 0;
+ c->c_loops = 0;
+ c->c_filename = filename;
+ return 1;
+
+ 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);
+}
+
+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;
+ if (byte < 0 || byte > 255) {
+ fprintf(stderr, "XXX compiling bad byte: %d\n", byte);
+ abort();
+ err_setstr(SystemError, "com_addbyte: byte out of range");
+ c->c_errors++;
+ }
+ 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;
+{
+ 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 lastanchor = 0;
+ 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;
+ lastanchor = anchor;
+ anchor -= prev;
+ }
+}
+
+/* Handle constants 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 (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);
+}
+
+static void
+com_addopname(c, op, n)
+ struct compiling *c;
+ int op;
+ node *n;
+{
+ object *v;
+ int i;
+ char *name;
+ if (TYPE(n) == STAR)
+ name = "*";
+ else {
+ REQ(n, NAME);
+ name = STR(n);
+ }
+ if ((v = newstringobject(name)) == NULL) {
+ c->c_errors++;
+ i = 255;
+ }
+ else {
+ i = com_addname(c, v);
+ DECREF(v);
+ }
+ com_addoparg(c, op, i);
+}
+
+static object *
+parsenumber(s)
+ char *s;
+{
+ extern long strtol();
+ extern double atof();
+ char *end = s;
+ long x;
+ x = strtol(s, &end, 0);
+ if (*end == '\0')
+ return newintobject(x);
+ if (*end == '.' || *end == 'e' || *end == 'E')
+ return newfloatobject(atof(s));
+ err_setstr(RuntimeError, "bad number syntax");
+ return NULL;
+}
+
+static object *
+parsestr(s)
+ char *s;
+{
+ object *v;
+ int len;
+ char *buf;
+ char *p;
+ int c;
+ if (*s != '\'') {
+ err_badcall();
+ return NULL;
+ }
+ s++;
+ len = strlen(s);
+ if (s[--len] != '\'') {
+ err_badcall();
+ return NULL;
+ }
+ if (strchr(s, '\\') == NULL)
+ return newsizedstringobject(s, len);
+ v = newsizedstringobject((char *)NULL, len);
+ p = buf = getstringvalue(v);
+ while (*s != '\0' && *s != '\'') {
+ if (*s != '\\') {
+ *p++ = *s++;
+ continue;
+ }
+ s++;
+ switch (*s++) {
+ /* XXX This assumes ASCII! */
+ 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 'E': *p++ = '\033'; break; /* ESC, not C */
+ 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(*s)) {
+ sscanf(s, "%x", &c);
+ *p++ = c;
+ do {
+ s++;
+ } while (isxdigit(*s));
+ break;
+ }
+ /* FALLTHROUGH */
+ default: *p++ = '\\'; *p++ = s[-1]; break;
+ }
+ }
+ resizestring(&v, (int)(p - buf));
+ return v;
+}
+
+static void
+com_list_constructor(c, n)
+ struct compiling *c;
+ node *n;
+{
+ int len;
+ int i;
+ object *v, *w;
+ 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);
+}
+
+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);
+ else
+ com_node(c, CHILD(n, 1));
+ break;
+ case LSQB:
+ if (TYPE(CHILD(n, 1)) == RSQB)
+ com_addoparg(c, BUILD_LIST, 0);
+ else
+ com_list_constructor(c, CHILD(n, 1));
+ break;
+ case LBRACE:
+ com_addoparg(c, BUILD_MAP, 0);
+ break;
+ case BACKQUOTE:
+ com_node(c, CHILD(n, 1));
+ com_addbyte(c, UNARY_CONVERT);
+ break;
+ case NUMBER:
+ if ((v = parsenumber(STR(ch))) == NULL) {
+ c->c_errors++;
+ i = 255;
+ }
+ else {
+ i = com_addconst(c, v);
+ DECREF(v);
+ }
+ com_addoparg(c, LOAD_CONST, i);
+ break;
+ case STRING:
+ if ((v = parsestr(STR(ch))) == NULL) {
+ c->c_errors++;
+ i = 255;
+ }
+ else {
+ i = com_addconst(c, v);
+ DECREF(v);
+ }
+ com_addoparg(c, LOAD_CONST, i);
+ break;
+ case NAME:
+ com_addopname(c, LOAD_NAME, ch);
+ break;
+ default:
+ fprintf(stderr, "node type %d\n", TYPE(ch));
+ err_setstr(SystemError, "com_atom: unexpected node type");
+ c->c_errors++;
+ }
+}
+
+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);
+ }
+ }
+ else {
+ com_node(c, CHILD(n, 0));
+ com_node(c, CHILD(n, 2));
+ com_addbyte(c, op+3);
+ }
+}
+
+static void
+com_apply_subscript(c, n)
+ struct compiling *c;
+ node *n;
+{
+ REQ(n, subscript);
+ if (NCH(n) == 1 && TYPE(CHILD(n, 0)) != COLON) {
+ /* It's a single subscript */
+ com_node(c, CHILD(n, 0));
+ com_addbyte(c, BINARY_SUBSCR);
+ }
+ else {
+ /* It's a slice: [expr] ':' [expr] */
+ com_slice(c, n, SLICE);
+ }
+}
+
+static void
+com_call_function(c, n)
+ struct compiling *c;
+ node *n; /* EITHER testlist OR ')' */
+{
+ if (TYPE(n) == RPAR) {
+ com_addbyte(c, UNARY_CALL);
+ }
+ else {
+ com_node(c, n);
+ com_addbyte(c, BINARY_CALL);
+ }
+}
+
+static void
+com_select_member(c, n)
+ struct compiling *c;
+ node *n;
+{
+ com_addopname(c, LOAD_ATTR, n);
+}
+
+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_apply_subscript(c, CHILD(n, 1));
+ break;
+ default:
+ err_setstr(SystemError,
+ "com_apply_trailer: unknown trailer type");
+ c->c_errors++;
+ }
+}
+
+static void
+com_factor(c, n)
+ struct compiling *c;
+ node *n;
+{
+ int i;
+ 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 {
+ com_atom(c, CHILD(n, 0));
+ for (i = 1; i < NCH(n); i++)
+ com_apply_trailer(c, CHILD(n, i));
+ }
+}
+
+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:
+ err_setstr(SystemError,
+ "com_term: term operator not *, / or %");
+ c->c_errors++;
+ op = 255;
+ }
+ com_addbyte(c, op);
+ }
+}
+
+static void
+com_expr(c, n)
+ struct compiling *c;
+ node *n;
+{
+ int i;
+ int op;
+ REQ(n, 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:
+ err_setstr(SystemError,
+ "com_expr: expr operator not + or -");
+ c->c_errors++;
+ op = 255;
+ }
+ com_addbyte(c, op);
+ }
+}
+
+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 EQUAL: return EQ;
+ case NAME: if (strcmp(STR(n), "in") == 0) return IN;
+ if (strcmp(STR(n), "is") == 0) return IS;
+ }
+ }
+ else if (NCH(n) == 2) {
+ int t2 = TYPE(CHILD(n, 1));
+ switch (TYPE(CHILD(n, 0))) {
+ case LESS: if (t2 == EQUAL) return LE;
+ if (t2 == GREATER) return NE;
+ break;
+ case GREATER: if (t2 == EQUAL) return GE;
+ break;
+ 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 <code to load b>
+ 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 <code to load c>
+ 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:
+ ****************************************************************/
+
+ 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_addbyte(c, ROT_THREE);
+ }
+ op = cmp_type(CHILD(n, i-1));
+ if (op == BAD) {
+ err_setstr(SystemError,
+ "com_comparison: unknown comparison op");
+ c->c_errors++;
+ }
+ com_addoparg(c, COMPARE_OP, op);
+ if (i+2 < NCH(n)) {
+ com_addfwref(c, JUMP_IF_FALSE, &anchor);
+ com_addbyte(c, POP_TOP);
+ }
+ }
+
+ 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);
+ }
+ if (anchor)
+ com_backpatch(c, anchor);
+}
+
+static void
+com_test(c, n)
+ struct compiling *c;
+ node *n;
+{
+ int i;
+ int anchor;
+ REQ(n, test); /* and_test ('and' and_test)* */
+ anchor = 0;
+ 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);
+ }
+ if (anchor)
+ com_backpatch(c, anchor);
+}
+
+static void
+com_list(c, n)
+ struct compiling *c;
+ node *n;
+{
+ /* exprlist: expr (',' expr)* [',']; likewise for testlist */
+ if (NCH(n) == 1) {
+ 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);
+ }
+}
+
+
+/* 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);
+}
+
+static void
+com_assign_slice(c, n, assigning)
+ struct compiling *c;
+ node *n;
+ int assigning;
+{
+ com_slice(c, n, assigning ? STORE_SLICE : DELETE_SLICE);
+}
+
+static void
+com_assign_subscript(c, n, assigning)
+ struct compiling *c;
+ node *n;
+ int assigning;
+{
+ com_node(c, n);
+ com_addbyte(c, assigning ? STORE_SUBSCR : DELETE_SUBSCR);
+}
+
+static void
+com_assign_trailer(c, n, assigning)
+ struct compiling *c;
+ node *n;
+ int assigning;
+{
+ char *name;
+ REQ(n, trailer);
+ switch (TYPE(CHILD(n, 0))) {
+ case LPAR: /* '(' [exprlist] ')' */
+ err_setstr(TypeError, "can't assign to function call");
+ c->c_errors++;
+ break;
+ case DOT: /* '.' NAME */
+ com_assign_attr(c, CHILD(n, 1), assigning);
+ break;
+ case LSQB: /* '[' subscript ']' */
+ n = CHILD(n, 1);
+ REQ(n, subscript); /* subscript: expr | [expr] ':' [expr] */
+ if (NCH(n) > 1 || TYPE(CHILD(n, 0)) == COLON)
+ com_assign_slice(c, n, assigning);
+ else
+ com_assign_subscript(c, CHILD(n, 0), assigning);
+ break;
+ default:
+ err_setstr(TypeError, "unknown trailer type");
+ c->c_errors++;
+ }
+}
+
+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)
+ com_addoparg(c, UNPACK_TUPLE, (NCH(n)+1)/2);
+ 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)
+ com_addoparg(c, UNPACK_LIST, (NCH(n)+1)/2);
+ 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);
+}
+
+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:
+ if (NCH(n) > 1) {
+ err_setstr(TypeError,
+ "can't assign to operator");
+ c->c_errors++;
+ return;
+ }
+ n = CHILD(n, 0);
+ break;
+
+ case comparison:
+ if (NCH(n) > 1) {
+ err_setstr(TypeError,
+ "can't assign to operator");
+ c->c_errors++;
+ return;
+ }
+ n = CHILD(n, 0);
+ break;
+
+ case expr:
+ if (NCH(n) > 1) {
+ err_setstr(TypeError,
+ "can't assign to operator");
+ c->c_errors++;
+ return;
+ }
+ n = CHILD(n, 0);
+ break;
+
+ case term:
+ if (NCH(n) > 1) {
+ err_setstr(TypeError,
+ "can't assign to operator");
+ c->c_errors++;
+ return;
+ }
+ n = CHILD(n, 0);
+ break;
+
+ case factor: /* ('+'|'-') factor | atom trailer* */
+ if (TYPE(CHILD(n, 0)) != atom) { /* '+' | '-' */
+ err_setstr(TypeError,
+ "can't assign to operator");
+ c->c_errors++;
+ return;
+ }
+ if (NCH(n) > 1) { /* trailer present */
+ int i;
+ com_node(c, CHILD(n, 0));
+ for (i = 1; i+1 < NCH(n); i++) {
+ 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 () = () ??? */
+ err_setstr(TypeError,
+ "can't assign to ()");
+ c->c_errors++;
+ return;
+ }
+ break;
+ case LSQB:
+ n = CHILD(n, 1);
+ if (TYPE(n) == RSQB) {
+ err_setstr(TypeError,
+ "can't assign to []");
+ c->c_errors++;
+ return;
+ }
+ com_assign_list(c, n, assigning);
+ return;
+ case NAME:
+ com_assign_name(c, CHILD(n, 0), assigning);
+ return;
+ default:
+ err_setstr(TypeError,
+ "can't assign to constant");
+ c->c_errors++;
+ return;
+ }
+ break;
+
+ default:
+ fprintf(stderr, "node type %d\n", TYPE(n));
+ err_setstr(SystemError, "com_assign: bad node");
+ c->c_errors++;
+ return;
+
+ }
+ }
+}
+
+static void
+com_expr_stmt(c, n)
+ struct compiling *c;
+ node *n;
+{
+ REQ(n, expr_stmt); /* exprlist ('=' exprlist)* NEWLINE */
+ com_node(c, CHILD(n, NCH(n)-2));
+ if (NCH(n) == 2) {
+ com_addbyte(c, PRINT_EXPR);
+ }
+ else {
+ int i;
+ for (i = 0; i < NCH(n)-3; i+=2) {
+ if (i+2 < NCH(n)-3)
+ com_addbyte(c, DUP_TOP);
+ com_assign(c, CHILD(n, i), 1/*assign*/);
+ }
+ }
+}
+
+static void
+com_print_stmt(c, n)
+ struct compiling *c;
+ node *n;
+{
+ int i;
+ REQ(n, print_stmt); /* 'print' (test ',')* [test] NEWLINE */
+ for (i = 1; i+1 < NCH(n); i += 2) {
+ com_node(c, CHILD(n, i));
+ com_addbyte(c, PRINT_ITEM);
+ }
+ if (TYPE(CHILD(n, NCH(n)-2)) != 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] NEWLINE */
+ if (!c->c_infunction) {
+ err_setstr(TypeError, "'return' outside function");
+ c->c_errors++;
+ }
+ if (NCH(n) == 2)
+ com_addoparg(c, LOAD_CONST, com_addconst(c, None));
+ else
+ com_node(c, CHILD(n, 1));
+ com_addbyte(c, RETURN_VALUE);
+}
+
+static void
+com_raise_stmt(c, n)
+ struct compiling *c;
+ node *n;
+{
+ REQ(n, raise_stmt); /* 'raise' expr [',' expr] NEWLINE */
+ com_node(c, CHILD(n, 1));
+ if (NCH(n) > 3)
+ com_node(c, CHILD(n, 3));
+ else
+ com_addoparg(c, LOAD_CONST, com_addconst(c, None));
+ com_addbyte(c, RAISE_EXCEPTION);
+}
+
+static void
+com_import_stmt(c, n)
+ struct compiling *c;
+ node *n;
+{
+ int i;
+ REQ(n, import_stmt);
+ /* 'import' NAME (',' NAME)* NEWLINE |
+ 'from' NAME 'import' ('*' | NAME (',' NAME)*) NEWLINE */
+ if (STR(CHILD(n, 0))[0] == 'f') {
+ /* 'from' NAME 'import' ... */
+ REQ(CHILD(n, 1), NAME);
+ com_addopname(c, IMPORT_NAME, CHILD(n, 1));
+ for (i = 3; i < NCH(n); i += 2)
+ com_addopname(c, IMPORT_FROM, CHILD(n, i));
+ com_addbyte(c, POP_TOP);
+ }
+ else {
+ /* 'import' ... */
+ for (i = 1; i < NCH(n); i += 2) {
+ com_addopname(c, IMPORT_NAME, CHILD(n, i));
+ com_addopname(c, STORE_NAME, CHILD(n, i));
+ }
+ }
+}
+
+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_node(c, CHILD(n, i+3));
+ com_addfwref(c, JUMP_FORWARD, &anchor);
+ com_backpatch(c, a);
+ 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 begin;
+ REQ(n, while_stmt); /* 'while' test ':' suite ['else' ':' suite] */
+ com_addfwref(c, SETUP_LOOP, &break_anchor);
+ 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);
+ c->c_loops++;
+ com_node(c, CHILD(n, 3));
+ c->c_loops--;
+ com_addoparg(c, JUMP_ABSOLUTE, begin);
+ com_backpatch(c, anchor);
+ com_addbyte(c, POP_TOP);
+ com_addbyte(c, POP_BLOCK);
+ 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 begin;
+ REQ(n, for_stmt);
+ /* 'for' exprlist 'in' exprlist ':' suite ['else' ':' suite] */
+ com_addfwref(c, SETUP_LOOP, &break_anchor);
+ com_node(c, CHILD(n, 3));
+ v = newintobject(0L);
+ if (v == NULL)
+ c->c_errors++;
+ com_addoparg(c, LOAD_CONST, com_addconst(c, v));
+ XDECREF(v);
+ begin = c->c_nexti;
+ com_addoparg(c, SET_LINENO, n->n_lineno);
+ com_addfwref(c, FOR_LOOP, &anchor);
+ com_assign(c, CHILD(n, 1), 1/*assigning*/);
+ c->c_loops++;
+ com_node(c, CHILD(n, 5));
+ c->c_loops--;
+ com_addoparg(c, JUMP_ABSOLUTE, begin);
+ com_backpatch(c, anchor);
+ com_addbyte(c, POP_BLOCK);
+ if (NCH(n) > 8)
+ com_node(c, CHILD(n, 8));
+ com_backpatch(c, break_anchor);
+}
+
+/* Although 'execpt' and 'finally' clauses can be combined
+ syntactically, they are compiled separately. In fact,
+ try: S
+ except E1: S1
+ except E2: S2
+ ...
+ finally: Sf
+ is equivalent to
+ try:
+ try: S
+ except E1: S1
+ except E2: S2
+ ...
+ finally: Sf
+ meaning that the 'finally' clause is entered even if things
+ go wrong again in an exception handler. Note that this is
+ not the case for exception handlers: at most one is entered.
+
+ Code generated for "try: S finally: Sf" is as follows:
+
+ SETUP_FINALLY L
+ <code for S>
+ POP_BLOCK
+ LOAD_CONST <nil>
+ L: <code for Sf>
+ 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
+ [] <code for S>
+ [] POP_BLOCK
+ [] JUMP_FORWARD L0
+
+ [tb, val, exc] L1: DUP )
+ [tb, val, exc, exc] <evaluate E1> )
+ [tb, val, exc, exc, E1] COMPARE_OP EXC_MATCH ) only if E1
+ [tb, val, exc, 1-or-0] JUMP_IF_FALSE L2 )
+ [tb, val, exc, 1] POP )
+ [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, 0] L2: POP
+ [tb, val, exc] DUP
+ .............................etc.......................
+
+ [tb, val, exc, 0] Ln+1: POP
+ [tb, val, exc] END_FINALLY # re-raise exception
+
+ [] L0: <next statement>
+
+ Of course, parts are not generated if Vi or Ei is not present.
+*/
+
+static void
+com_try_stmt(c, n)
+ struct compiling *c;
+ node *n;
+{
+ int finally_anchor = 0;
+ int except_anchor = 0;
+ REQ(n, try_stmt);
+ /* 'try' ':' suite (except_clause ':' suite)* ['finally' ':' suite] */
+
+ if (NCH(n) > 3 && TYPE(CHILD(n, NCH(n)-3)) != except_clause) {
+ /* Have a 'finally' clause */
+ com_addfwref(c, SETUP_FINALLY, &finally_anchor);
+ }
+ if (NCH(n) > 3 && TYPE(CHILD(n, 3)) == except_clause) {
+ /* Have an 'except' clause */
+ com_addfwref(c, SETUP_EXCEPT, &except_anchor);
+ }
+ com_node(c, CHILD(n, 2));
+ if (except_anchor) {
+ int end_anchor = 0;
+ int i;
+ node *ch;
+ com_addbyte(c, POP_BLOCK);
+ com_addfwref(c, JUMP_FORWARD, &end_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 [',' expr]] */
+ if (except_anchor == 0) {
+ err_setstr(TypeError,
+ "default 'except:' must be last");
+ c->c_errors++;
+ break;
+ }
+ except_anchor = 0;
+ com_addoparg(c, SET_LINENO, ch->n_lineno);
+ if (NCH(ch) > 1) {
+ com_addbyte(c, DUP_TOP);
+ com_node(c, CHILD(ch, 1));
+ com_addoparg(c, COMPARE_OP, EXC_MATCH);
+ com_addfwref(c, JUMP_IF_FALSE, &except_anchor);
+ com_addbyte(c, POP_TOP);
+ }
+ com_addbyte(c, POP_TOP);
+ if (NCH(ch) > 3)
+ com_assign(c, CHILD(ch, 3), 1/*assigning*/);
+ else
+ com_addbyte(c, POP_TOP);
+ com_addbyte(c, POP_TOP);
+ com_node(c, CHILD(n, i+2));
+ com_addfwref(c, JUMP_FORWARD, &end_anchor);
+ if (except_anchor) {
+ com_backpatch(c, except_anchor);
+ com_addbyte(c, POP_TOP);
+ }
+ }
+ com_addbyte(c, END_FINALLY);
+ com_backpatch(c, end_anchor);
+ }
+ if (finally_anchor) {
+ node *ch;
+ com_addbyte(c, POP_BLOCK);
+ com_addoparg(c, LOAD_CONST, com_addconst(c, None));
+ 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);
+ }
+}
+
+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);
+ }
+ }
+}
+
+static void
+com_funcdef(c, n)
+ struct compiling *c;
+ node *n;
+{
+ object *v;
+ REQ(n, funcdef); /* funcdef: 'def' NAME parameters ':' suite */
+ v = (object *)compile(n, c->c_filename);
+ if (v == NULL)
+ c->c_errors++;
+ else {
+ int i = com_addconst(c, v);
+ com_addoparg(c, LOAD_CONST, i);
+ com_addbyte(c, BUILD_FUNCTION);
+ com_addopname(c, STORE_NAME, CHILD(n, 1));
+ DECREF(v);
+ }
+}
+
+static void
+com_bases(c, n)
+ struct compiling *c;
+ node *n;
+{
+ int i, nbases;
+ REQ(n, baselist);
+ /*
+ baselist: atom arguments (',' atom arguments)*
+ arguments: '(' [testlist] ')'
+ */
+ for (i = 0; i < NCH(n); i += 3)
+ com_node(c, CHILD(n, i));
+ com_addoparg(c, BUILD_TUPLE, (NCH(n)+1) / 3);
+}
+
+static void
+com_classdef(c, n)
+ struct compiling *c;
+ node *n;
+{
+ object *v;
+ REQ(n, classdef);
+ /*
+ classdef: 'class' NAME parameters ['=' baselist] ':' suite
+ baselist: atom arguments (',' atom arguments)*
+ arguments: '(' [testlist] ')'
+ */
+ if (NCH(n) == 7)
+ com_bases(c, CHILD(n, 4));
+ else
+ com_addoparg(c, LOAD_CONST, com_addconst(c, None));
+ v = (object *)compile(n, c->c_filename);
+ if (v == NULL)
+ c->c_errors++;
+ else {
+ int i = com_addconst(c, v);
+ com_addoparg(c, LOAD_CONST, i);
+ com_addbyte(c, BUILD_FUNCTION);
+ com_addbyte(c, UNARY_CALL);
+ com_addbyte(c, BUILD_CLASS);
+ 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 flow_stmt:
+ com_node(c, CHILD(n, 0));
+ break;
+
+ case simple_stmt:
+ 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 NEWLINE */
+ com_assign(c, CHILD(n, 1), 0/*delete*/);
+ break;
+ case pass_stmt:
+ break;
+ case break_stmt:
+ if (c->c_loops == 0) {
+ err_setstr(TypeError, "'break' outside loop");
+ c->c_errors++;
+ }
+ com_addbyte(c, BREAK_LOOP);
+ 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 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);
+ 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);
+ break;
+ case expr:
+ com_expr(c, n);
+ break;
+ case term:
+ com_term(c, n);
+ break;
+ case factor:
+ com_factor(c, n);
+ break;
+ case atom:
+ com_atom(c, n);
+ break;
+
+ default:
+ fprintf(stderr, "node type %d\n", TYPE(n));
+ err_setstr(SystemError, "com_node: unexpected node type");
+ c->c_errors++;
+ }
+}
+
+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_addopname(c, STORE_NAME, CHILD(n, 0));
+}
+
+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;
+ com_addoparg(c, UNPACK_TUPLE, (NCH(n)+1)/2);
+ for (i = 0; i < NCH(n); i += 2)
+ com_fpdef(c, CHILD(n, i));
+ }
+}
+
+static void
+com_file_input(c, n)
+ struct compiling *c;
+ node *n;
+{
+ int i;
+ REQ(n, file_input); /* (NEWLINE | stmt)* ENDMARKER */
+ 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;
+{
+ node *ch;
+ REQ(n, funcdef); /* funcdef: 'def' NAME parameters ':' suite */
+ ch = CHILD(n, 2); /* parameters: '(' [fplist] ')' */
+ ch = CHILD(ch, 1); /* ')' | fplist */
+ if (TYPE(ch) == RPAR)
+ com_addbyte(c, REFUSE_ARGS);
+ else {
+ com_addbyte(c, REQUIRE_ARGS);
+ com_fplist(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_addbyte(c, RETURN_VALUE);
+}
+
+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 */
+ com_addbyte(c, REFUSE_ARGS);
+ n = CHILD(n, 0);
+ if (TYPE(n) != NEWLINE)
+ com_node(c, n);
+ com_addoparg(c, LOAD_CONST, com_addconst(c, None));
+ com_addbyte(c, RETURN_VALUE);
+ break;
+
+ case file_input: /* A whole file, or built-in function exec() */
+ com_addbyte(c, REFUSE_ARGS);
+ com_file_input(c, n);
+ com_addoparg(c, LOAD_CONST, com_addconst(c, None));
+ com_addbyte(c, RETURN_VALUE);
+ break;
+
+ case expr_input: /* Built-in function eval() */
+ com_addbyte(c, REFUSE_ARGS);
+ com_node(c, CHILD(n, 0));
+ com_addbyte(c, RETURN_VALUE);
+ break;
+
+ case eval_input: /* Built-in function input() */
+ com_addbyte(c, REFUSE_ARGS);
+ com_node(c, CHILD(n, 0));
+ com_addbyte(c, RETURN_VALUE);
+ break;
+
+ case funcdef: /* A function definition */
+ compile_funcdef(c, n);
+ break;
+
+ case classdef: /* A class definition */
+ /* 'class' NAME parameters ['=' baselist] ':' suite */
+ com_addbyte(c, REFUSE_ARGS);
+ com_node(c, CHILD(n, NCH(n)-1));
+ com_addbyte(c, LOAD_LOCALS);
+ com_addbyte(c, RETURN_VALUE);
+ break;
+
+ default:
+ fprintf(stderr, "node type %d\n", TYPE(n));
+ err_setstr(SystemError, "compile_node: unexpected node type");
+ c->c_errors++;
+ }
+}
+
+codeobject *
+compile(n, filename)
+ node *n;
+ char *filename;
+{
+ struct compiling sc;
+ codeobject *co;
+ if (!com_init(&sc, filename))
+ return NULL;
+ compile_node(&sc, n);
+ com_done(&sc);
+ if (sc.c_errors == 0)
+ co = newcodeobject(sc.c_code, sc.c_consts, sc.c_names, filename);
+ else
+ co = NULL;
+ com_free(&sc);
+ return co;
+}