| /*********************************************************** |
| 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> |
| |
| extern int errno; |
| |
| #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, 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; |
| 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 strtod(); |
| char *end = s; |
| long x; |
| double xx; |
| errno = 0; |
| x = strtol(s, &end, 0); |
| if (*end == '\0') { |
| if (errno != 0) { |
| err_setstr(RuntimeError, "integer constant too large"); |
| return NULL; |
| } |
| return newintobject(x); |
| } |
| errno = 0; |
| xx = strtod(s, &end); |
| if (*end == '\0') { |
| if (errno != 0) { |
| err_setstr(RuntimeError, "float constant too large"); |
| return NULL; |
| } |
| return newfloatobject(xx); |
| } |
| 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++; |
| } |
| } |
| |
| /* Optimization for local and global variables. |
| |
| Attempt to replace all LOAD_NAME instructions that refer to a local |
| variable with LOAD_LOCAL instructions, and all that refer to a global |
| variable with LOAD_GLOBAL instructions. |
| |
| To find all local variables, we check all STORE_NAME and IMPORT_FROM |
| instructions. This yields all local variables, including arguments, |
| function definitions, class definitions and import statements. |
| |
| There is one leak: 'from foo import *' introduces local variables |
| that we can't know while compiling. If this is the case, LOAD_GLOBAL |
| instructions are not generated -- LOAD_NAME is left in place for |
| globals, since it first checks for globals (LOAD_LOCAL is still used |
| for recognized locals, since it doesn't hurt). |
| |
| This optimization means that using the same name as a global and |
| as a local variable within the same scope is now illegal, which |
| is a change to the language! Also using eval() to introduce new |
| local variables won't work. But both were bad practice at best. |
| |
| The optimization doesn't save much: basically, it saves one |
| unsuccessful dictionary lookup per global (or built-in) variable |
| reference. On the (slow!) Mac Plus, with 4 local variables, |
| this saving was measured to be about 0.18 ms. We might save more |
| by using a different data structure to hold local variables, like |
| an array indexed by variable number. |
| |
| NB: this modifies the string object co->co_code! |
| */ |
| |
| static void |
| optimizer(co) |
| codeobject *co; |
| { |
| unsigned char *next_instr, *cur_instr; |
| object *locals; |
| int opcode; |
| int oparg; |
| object *name; |
| int star_used; |
| |
| #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(co->co_names, (i))) |
| |
| locals = newdictobject(); |
| if (locals == NULL) { |
| err_clear(); |
| return; /* For now, this is OK */ |
| } |
| |
| next_instr = (unsigned char *) GETSTRINGVALUE(co->co_code); |
| for (;;) { |
| opcode = NEXTOP(); |
| if (opcode == STOP_CODE) |
| break; |
| if (HAS_ARG(opcode)) |
| oparg = NEXTARG(); |
| if (opcode == STORE_NAME || opcode == IMPORT_FROM) { |
| name = GETNAMEOBJ(oparg); |
| if (dict2insert(locals, name, None) != 0) { |
| DECREF(locals); |
| return; /* Sorry */ |
| } |
| } |
| } |
| |
| star_used = (dictlookup(locals, "*") != NULL); |
| next_instr = (unsigned char *) GETSTRINGVALUE(co->co_code); |
| for (;;) { |
| cur_instr = next_instr; |
| opcode = NEXTOP(); |
| if (opcode == STOP_CODE) |
| break; |
| if (HAS_ARG(opcode)) |
| oparg = NEXTARG(); |
| if (opcode == LOAD_NAME) { |
| name = GETNAMEOBJ(oparg); |
| if (dictlookup(locals, getstringvalue(name)) != NULL) |
| *cur_instr = LOAD_LOCAL; |
| else if (!star_used) |
| *cur_instr = LOAD_GLOBAL; |
| } |
| } |
| |
| DECREF(locals); |
| } |
| |
| 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); |
| if (co != NULL) |
| optimizer(co); |
| return co; |
| } |