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| author | Skip Montanaro <[email protected]> | 2021-02-16 14:40:46 -0600 |
|---|---|---|
| committer | Skip Montanaro <[email protected]> | 2021-02-16 14:40:46 -0600 |
| commit | a19a216bc60160c162e616145ef091dd18ce4e61 (patch) | |
| tree | fa4bdff21f9b04a125c84a2bfab8a1c738359e15 /src/compile.c | |
| download | python-0.9.1-patched-QoL-a19a216bc60160c162e616145ef091dd18ce4e61.tar.xz python-0.9.1-patched-QoL-a19a216bc60160c162e616145ef091dd18ce4e61.zip | |
Python 0.9.1 as posted in alt.sources
Diffstat (limited to 'src/compile.c')
| -rw-r--r-- | src/compile.c | 1772 |
1 files changed, 1772 insertions, 0 deletions
diff --git a/src/compile.c b/src/compile.c new file mode 100644 index 0000000..7904dba --- /dev/null +++ b/src/compile.c @@ -0,0 +1,1772 @@ +/*********************************************************** +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; +} |
