gecko-dev/js/ref/jsatom.c
brendan%netscape.com 347aaac8d3 js.c jsemit.c jsemit.h jsgc.c jsinterp.c jsopcode.c jsopcode.def
- Switch improvements:
  - JSOP_CONDSWITCH is a 1 byte nop, not variable length with the same kind
    of immediate operand as JSOP_LOOKUPSWITCH (which is useless except for
    decompilation).  New scheme uses SRC_COMMA notes on each JSOP_CASE opcode,
    usually 2 bytes per note, and a typically-1-byte 2nd offset on SRC_SWITCH:
      1 + 2 * ncases
    vs. the previous JSOP_LOOKUPSWITCH immediate, which consumed:
      4 * ncases
    bytes after the switch opcode just for decompilation.
  - SRC_SWITCH has two offsets, first to end of switch as before, the second
    to first case if JSOP_CONDSWITCH, for decompilation.
  - Optimize switches with all-constant cases using JSOP_TABLESWITH, or if
    that can't be used, JSOP_LOOKUPSWITCH, before falling back on ECMAv2's
    JSOP_CONDSWITCH.
  - Use cx->gcDisabled when evaluating case exprs at compile time for old,
    pre-ECMAv2 switches, to prevent branch-callback-based GC invocations
    from ripping apart the unrooted temporary script for each case expr.
  - Fixed up stale SRC_SWITCH comments in jsemit.h.

jsemit.c jsemit.h
  - TREE_CONTEXT_INIT to match ATOM_LIST_INIT, not English word order.
  - Reorganized JSCodeGenerator to sort of match argument order to
    js_InitCodeGenerator.
  - Got rid of confusing CG_RESET* macros and used memset(cg, 0, sizeof *cg)
    and non-zero-default init in js_InitCodeGenerator.  js_ResetCodeGenerator
    just releases the code and temp arena pools and leaves the cg in a state
    where it must be re-initialized (as before, but more obvious).
  - In the same spirit, don't do partial "resets" or src and trynotes in their
    js_FinishTaking*Notes functions -- those are friends of jsscript.c and are
    not general, idempotent functions.

jsapi.c jsapi.h jsarray.c jsatom.c jsatom.h jscntxt.c jsemit.c jsmsg.def
jsnum.c jsobj.c jsopcode.c jsregexp.c jsscan.c jsstr.c jsxdrapi.
  - Use PR_snprintf rather than sprintf always, so we don't have to worry
    about systems with 64-bit longs that overflow 12-byte buffers and open
    Morris-Worm-type security holes.
  - Trim extra spaces, fix hanging indentation, and similar anal retention.
  - Renamed JSMSG_BAD_PROTO_SORT to JSMSG_BAD_SORT_ARG cuz that's what it
    is complaining about.
  - SRC_CATCHGUARD still lived in comments, but it's SRC_CATCH in code.

jscntxt.c jscntxt.h jsinterp.c
  - Packed nearby JSPackedBools and added a new one: gcDisabled, for use by
    jsemit.c's pre-ECMAv2 switch case expr eval.
  - Rip out old js_InterpreterHooks stuff from original liveconnect (moja).
  - Remove javaData and savedErrors from JSContext.  Leaving it to fur or
    shaver to remove javaData from jsscript.h.
1998-09-08 05:39:51 +00:00

666 lines
16 KiB
C

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* The contents of this file are subject to the Netscape Public License
* Version 1.0 (the "NPL"); you may not use this file except in
* compliance with the NPL. You may obtain a copy of the NPL at
* http://www.mozilla.org/NPL/
*
* Software distributed under the NPL is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
* for the specific language governing rights and limitations under the
* NPL.
*
* The Initial Developer of this code under the NPL is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All Rights
* Reserved.
*/
/*
* JS atom table.
*/
#include "jsstddef.h"
#include <stdlib.h>
#include <string.h>
#include "prtypes.h"
#include "prassert.h"
#include "prhash.h"
#include "prprintf.h"
#include "jsapi.h"
#include "jsatom.h"
#include "jscntxt.h"
#include "jsgc.h"
#include "jslock.h"
#include "jsnum.h"
#include "jsopcode.h"
#include "jsstr.h"
/*
* Keep this in sync with jspubtd.h -- an assertion below will insist that
* its length match the JSType enum's JSTYPE_LIMIT limit value.
*/
char *js_type_str[] = {
"undefined",
"object",
"function",
"string",
"number",
"boolean",
};
char *js_boolean_str[] = {
js_false_str,
js_true_str
};
char js_Array_str[] = "Array";
char js_Math_str[] = "Math";
char js_Object_str[] = "Object";
char js_anonymous_str[] = "anonymous";
char js_arguments_str[] = "arguments";
char js_arity_str[] = "arity";
char js_assign_str[] = "assign";
char js_callee_str[] = "callee";
char js_caller_str[] = "caller";
char js_class_prototype_str[] = "prototype";
char js_constructor_str[] = "constructor";
char js_count_str[] = "__count__";
char js_eval_str[] = "eval";
char js_index_str[] = "index";
char js_input_str[] = "input";
char js_length_str[] = "length";
char js_name_str[] = "name";
char js_parent_str[] = "__parent__";
char js_proto_str[] = "__proto__";
char js_toSource_str[] = "toSource";
char js_toString_str[] = "toString";
char js_valueOf_str[] = "valueOf";
#define HASH_OBJECT(o) ((prhashcode)(o) >> JSVAL_TAGBITS)
#define HASH_INT(i) ((prhashcode)(i))
#define HASH_DOUBLE(dp) ((prhashcode)(((uint32*)(dp))[0] ^ ((uint32*)(dp))[1]))
#define HASH_BOOLEAN(b) ((prhashcode)(b))
PR_STATIC_CALLBACK(prhashcode)
js_hash_atom_key(const void *key)
{
jsval v;
jsdouble *dp;
/* Order JSVAL_IS_* tests by likelihood of success. */
v = (jsval)key;
if (JSVAL_IS_STRING(v))
return js_HashString(JSVAL_TO_STRING(v));
if (JSVAL_IS_INT(v))
return HASH_INT(JSVAL_TO_INT(v));
if (JSVAL_IS_DOUBLE(v)) {
dp = JSVAL_TO_DOUBLE(v);
return HASH_DOUBLE(dp);
}
if (JSVAL_IS_OBJECT(v))
return HASH_OBJECT(JSVAL_TO_OBJECT(v));
if (JSVAL_IS_BOOLEAN(v))
return HASH_BOOLEAN(JSVAL_TO_BOOLEAN(v));
return (prhashcode)v;
}
PR_STATIC_CALLBACK(intN)
js_compare_atom_keys(const void *k1, const void *k2)
{
jsval v1, v2;
v1 = (jsval)k1, v2 = (jsval)k2;
if (JSVAL_IS_STRING(v1) && JSVAL_IS_STRING(v2))
return !js_CompareStrings(JSVAL_TO_STRING(v1), JSVAL_TO_STRING(v2));
if (JSVAL_IS_DOUBLE(v1) && JSVAL_IS_DOUBLE(v2)) {
double d1 = *JSVAL_TO_DOUBLE(v1);
double d2 = *JSVAL_TO_DOUBLE(v2);
if (JSDOUBLE_IS_NaN(d1))
return JSDOUBLE_IS_NaN(d2);
#ifdef XP_PC
/* XXX MSVC miscompiles such that (NaN == 0) */
if (JSDOUBLE_IS_NaN(d2))
return JS_FALSE;
#endif
return d1 == d2;
}
return v1 == v2;
}
PR_STATIC_CALLBACK(int)
js_compare_stub(const void *v1, const void *v2)
{
return 1;
}
PR_STATIC_CALLBACK(void *)
js_alloc_atom_space(void *priv, size_t size)
{
return malloc(size);
}
PR_STATIC_CALLBACK(void)
js_free_atom_space(void *priv, void *item)
{
free(item);
}
PR_STATIC_CALLBACK(PRHashEntry *)
js_alloc_atom(void *priv, const void *key)
{
JSAtomState *state = priv;
JSAtom *atom;
atom = malloc(sizeof(JSAtom));
if (!atom)
return NULL;
#ifdef JS_THREADSAFE
state->tablegen++;
#endif
atom->entry.key = key;
atom->entry.value = NULL;
atom->flags = 0;
atom->kwindex = -1;
atom->number = state->number++;
return &atom->entry;
}
PR_STATIC_CALLBACK(void)
js_free_atom(void *priv, PRHashEntry *he, uintN flag)
{
if (flag != HT_FREE_ENTRY)
return;
#ifdef JS_THREADSAFE
((JSAtomState *)priv)->tablegen++;
#endif
free(he);
}
static PRHashAllocOps atom_alloc_ops = {
js_alloc_atom_space, js_free_atom_space,
js_alloc_atom, js_free_atom
};
#define JS_ATOM_HASH_SIZE 1024
JSBool
js_InitAtomState(JSContext *cx, JSAtomState *state)
{
uintN i;
state->runtime = cx->runtime;
state->number = 0;
state->table = PR_NewHashTable(JS_ATOM_HASH_SIZE, js_hash_atom_key,
js_compare_atom_keys, js_compare_stub,
&atom_alloc_ops, state);
if (!state->table) {
JS_ReportOutOfMemory(cx);
return JS_FALSE;
}
#ifdef JS_THREADSAFE
js_NewLock(&state->lock);
state->tablegen = 0;
#endif
#define FROB(lval,str) { \
if (!(state->lval = js_Atomize(cx, str, strlen(str), ATOM_PINNED))) { \
js_FreeAtomState(cx, state); \
return JS_FALSE; \
} \
}
PR_ASSERT(sizeof js_type_str / sizeof js_type_str[0] == JSTYPE_LIMIT);
for (i = 0; i < JSTYPE_LIMIT; i++)
FROB(typeAtoms[i], js_type_str[i]);
FROB(booleanAtoms[0], js_false_str);
FROB(booleanAtoms[1], js_true_str);
FROB(nullAtom, js_null_str);
FROB(ArrayAtom, js_Array_str);
FROB(MathAtom, js_Math_str);
FROB(ObjectAtom, js_Object_str);
FROB(anonymousAtom, js_anonymous_str);
FROB(argumentsAtom, js_arguments_str);
FROB(arityAtom, js_arity_str);
FROB(assignAtom, js_assign_str);
FROB(calleeAtom, js_callee_str);
FROB(callerAtom, js_caller_str);
FROB(classPrototypeAtom, js_class_prototype_str);
FROB(constructorAtom, js_constructor_str);
FROB(countAtom, js_count_str);
FROB(indexAtom, js_index_str);
FROB(inputAtom, js_input_str);
FROB(lengthAtom, js_length_str);
FROB(nameAtom, js_name_str);
FROB(parentAtom, js_parent_str);
FROB(protoAtom, js_proto_str);
FROB(toSourceAtom, js_toSource_str);
FROB(toStringAtom, js_toString_str);
FROB(valueOfAtom, js_valueOf_str);
#undef FROB
return JS_TRUE;
}
void
js_FreeAtomState(JSContext *cx, JSAtomState *state)
{
state->runtime = NULL;
PR_HashTableDestroy(state->table);
state->table = NULL;
state->number = 0;
#ifdef JS_THREADSAFE
js_DestroyLock(&state->lock);
#endif
}
typedef struct MarkArgs {
JSRuntime *runtime;
JSGCThingMarker mark;
} MarkArgs;
PR_STATIC_CALLBACK(intN)
js_atom_marker(PRHashEntry *he, intN i, void *arg)
{
JSAtom *atom;
jsval key;
MarkArgs *args;
atom = (JSAtom *)he;
if (atom->flags & ATOM_PINNED) {
atom->flags |= ATOM_MARK;
key = ATOM_KEY(atom);
if (JSVAL_IS_GCTHING(key)) {
args = arg;
args->mark(args->runtime, JSVAL_TO_GCTHING(key));
}
}
return HT_ENUMERATE_NEXT;
}
void
js_MarkAtomState(JSAtomState *state, JSGCThingMarker mark)
{
MarkArgs args;
args.runtime = state->runtime;
args.mark = mark;
PR_HashTableEnumerateEntries(state->table, js_atom_marker, &args);
}
PR_STATIC_CALLBACK(intN)
js_atom_sweeper(PRHashEntry *he, intN i, void *arg)
{
JSAtom *atom;
atom = (JSAtom *)he;
if (atom->flags & ATOM_MARK) {
atom->flags &= ~ATOM_MARK;
return HT_ENUMERATE_NEXT;
}
PR_ASSERT((atom->flags & ATOM_PINNED) == 0);
atom->entry.key = NULL;
atom->flags = 0;
return HT_ENUMERATE_REMOVE;
}
void
js_SweepAtomState(JSAtomState *state)
{
PR_HashTableEnumerateEntries(state->table, js_atom_sweeper, NULL);
}
PR_STATIC_CALLBACK(intN)
js_atom_unpinner(PRHashEntry *he, intN i, void *arg)
{
JSAtom *atom;
atom = (JSAtom *)he;
atom->flags &= ~ATOM_PINNED;
return HT_ENUMERATE_NEXT;
}
void
js_UnpinPinnedAtoms(JSAtomState *state)
{
PR_HashTableEnumerateEntries(state->table, js_atom_unpinner, NULL);
}
static JSAtom *
js_AtomizeHashedKey(JSContext *cx, jsval key, prhashcode keyHash, uintN flags)
{
JSAtomState *state;
PRHashTable *table;
PRHashEntry *he, **hep;
JSAtom *atom;
state = &cx->runtime->atomState;
JS_LOCK(&state->lock,cx);
table = state->table;
hep = PR_HashTableRawLookup(table, keyHash, (void *)key);
if ((he = *hep) == NULL) {
he = PR_HashTableRawAdd(table, hep, keyHash, (void *)key, NULL);
if (!he) {
JS_ReportOutOfMemory(cx);
atom = NULL;
goto out;
}
}
atom = (JSAtom *)he;
atom->flags |= flags;
out:
JS_UNLOCK(&state->lock,cx);
return atom;
}
JSAtom *
js_AtomizeObject(JSContext *cx, JSObject *obj, uintN flags)
{
jsval key;
prhashcode keyHash;
/* XXX must be set in the following order or MSVC1.52 will crash */
keyHash = HASH_OBJECT(obj);
key = OBJECT_TO_JSVAL(obj);
return js_AtomizeHashedKey(cx, key, keyHash, flags);
}
JSAtom *
js_AtomizeBoolean(JSContext *cx, JSBool b, uintN flags)
{
jsval key;
prhashcode keyHash;
key = BOOLEAN_TO_JSVAL(b);
keyHash = HASH_BOOLEAN(b);
return js_AtomizeHashedKey(cx, key, keyHash, flags);
}
JSAtom *
js_AtomizeInt(JSContext *cx, jsint i, uintN flags)
{
jsval key;
prhashcode keyHash;
key = INT_TO_JSVAL(i);
keyHash = HASH_INT(i);
return js_AtomizeHashedKey(cx, key, keyHash, flags);
}
JSAtom *
js_AtomizeDouble(JSContext *cx, jsdouble d, uintN flags)
{
jsdouble *dp;
prhashcode keyHash;
jsval key;
JSAtomState *state;
PRHashTable *table;
PRHashEntry *he, **hep;
JSAtom *atom;
#if PR_ALIGN_OF_DOUBLE == 8
dp = &d;
#else
char alignbuf[16];
dp = (jsdouble *)&alignbuf[8 - ((pruword)&alignbuf & 7)];
*dp = d;
#endif
keyHash = HASH_DOUBLE(dp);
key = DOUBLE_TO_JSVAL(dp);
state = &cx->runtime->atomState;
JS_LOCK(&state->lock,cx);
table = state->table;
hep = PR_HashTableRawLookup(table, keyHash, (void *)key);
if ((he = *hep) == NULL) {
#ifdef JS_THREADSAFE
uint32 gen = state->tablegen;
#endif
JS_UNLOCK(&state->lock,cx);
if (!js_NewDoubleValue(cx, d, &key))
return NULL;
JS_LOCK(&state->lock,cx);
#ifdef JS_THREADSAFE
if (state->tablegen != gen) {
hep = PR_HashTableRawLookup(table, keyHash, (void *)key);
if ((he = *hep) != NULL) {
atom = (JSAtom *)he;
goto out;
}
}
#endif
he = PR_HashTableRawAdd(table, hep, keyHash, (void *)key, NULL);
if (!he) {
JS_ReportOutOfMemory(cx);
atom = NULL;
goto out;
}
}
atom = (JSAtom *)he;
atom->flags |= flags;
out:
JS_UNLOCK(&state->lock,cx);
return atom;
}
JSAtom *
js_AtomizeString(JSContext *cx, JSString *str, uintN flags)
{
prhashcode keyHash;
jsval key;
JSAtomState *state;
PRHashTable *table;
PRHashEntry *he, **hep;
JSAtom *atom;
keyHash = js_HashString(str);
key = STRING_TO_JSVAL(str);
state = &cx->runtime->atomState;
JS_LOCK(&state->lock,cx);
table = state->table;
hep = PR_HashTableRawLookup(table, keyHash, (void *)key);
if ((he = *hep) == NULL) {
if (flags & ATOM_TMPSTR) {
#ifdef JS_THREADSAFE
uint32 gen = state->tablegen;
#endif
JS_UNLOCK(&state->lock,cx);
flags &= ~ATOM_TMPSTR;
if (flags & ATOM_NOCOPY) {
flags &= ~ATOM_NOCOPY;
str = js_NewString(cx, str->chars, str->length, 0);
} else {
str = js_NewStringCopyN(cx, str->chars, str->length, 0);
}
if (!str)
return NULL;
key = STRING_TO_JSVAL(str);
JS_LOCK(&state->lock,cx);
#ifdef JS_THREADSAFE
if (state->tablegen != gen) {
hep = PR_HashTableRawLookup(table, keyHash, (void *)key);
if ((he = *hep) != NULL) {
atom = (JSAtom *)he;
goto out;
}
}
#endif
}
he = PR_HashTableRawAdd(table, hep, keyHash, (void *)key, NULL);
if (!he) {
JS_ReportOutOfMemory(cx);
atom = NULL;
goto out;
}
}
atom = (JSAtom *)he;
atom->flags |= flags;
out:
JS_UNLOCK(&state->lock,cx);
return atom;
}
JS_FRIEND_API(JSAtom *)
js_Atomize(JSContext *cx, const char *bytes, size_t length, uintN flags)
{
jschar *chars;
JSString *str;
JSAtom *atom;
#if PR_ALIGN_OF_DOUBLE == 8
union { jsdouble d; JSString s; } u;
str = &u.s;
#else
char alignbuf[16];
str = (JSString *)&alignbuf[8 - ((pruword)&alignbuf & 7)];
#endif
chars = js_InflateString(cx, bytes, length);
if (!chars)
return NULL;
str->chars = chars;
str->length = length;
atom = js_AtomizeString(cx, str, ATOM_TMPSTR | ATOM_NOCOPY | flags);
if (!atom || ATOM_TO_STRING(atom)->chars != chars)
JS_free(cx, chars);
return atom;
}
JS_FRIEND_API(JSAtom *)
js_AtomizeChars(JSContext *cx, const jschar *chars, size_t length, uintN flags)
{
JSString *str;
#if PR_ALIGN_OF_DOUBLE == 8
union { jsdouble d; JSString s; } u;
str = &u.s;
#else
char alignbuf[16];
str = (JSString *)&alignbuf[8 - ((pruword)&alignbuf & 7)];
#endif
str->chars = (jschar *)chars;
str->length = length;
return js_AtomizeString(cx, str, ATOM_TMPSTR | flags);
}
JSAtom *
js_AtomizeValue(JSContext *cx, jsval value, uintN flags)
{
if (JSVAL_IS_STRING(value))
return js_AtomizeString(cx, JSVAL_TO_STRING(value), flags);
if (JSVAL_IS_INT(value))
return js_AtomizeInt(cx, JSVAL_TO_INT(value), flags);
if (JSVAL_IS_DOUBLE(value))
return js_AtomizeDouble(cx, *JSVAL_TO_DOUBLE(value), flags);
if (JSVAL_IS_OBJECT(value))
return js_AtomizeObject(cx, JSVAL_TO_OBJECT(value), flags);
if (JSVAL_IS_BOOLEAN(value))
return js_AtomizeBoolean(cx, JSVAL_TO_BOOLEAN(value), flags);
return js_AtomizeHashedKey(cx, value, (prhashcode)value, flags);
}
JSAtom *
js_ValueToStringAtom(JSContext *cx, jsval v)
{
JSString *str;
str = js_ValueToString(cx, v);
if (!str)
return NULL;
return js_AtomizeString(cx, str, 0);
}
JSAtomListElement *
js_IndexAtom(JSContext *cx, JSAtom *atom, JSAtomList *al)
{
JSAtomListElement *ale;
ATOM_LIST_SEARCH(ale, al, atom);
if (!ale) {
PR_ARENA_ALLOCATE(ale, &cx->tempPool, sizeof(JSAtomListElement));
if (!ale) {
JS_ReportOutOfMemory(cx);
return NULL;
}
ale->atom = atom;
ale->index = (jsatomid) al->count++;
ale->next = al->list;
al->list = ale;
}
return ale;
}
JS_FRIEND_API(JSAtom *)
js_GetAtom(JSContext *cx, JSAtomMap *map, jsatomid i)
{
JSAtom *atom;
PR_ASSERT(map->vector && i < map->length);
if (!map->vector || i >= map->length) {
char numBuf[12];
PR_snprintf(numBuf, sizeof numBuf, "%lu", (unsigned long)i);
JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
JSMSG_BAD_ATOMIC_NUMBER, numBuf);
return NULL;
}
atom = map->vector[i];
PR_ASSERT(atom);
return atom;
}
JS_FRIEND_API(JSBool)
js_InitAtomMap(JSContext *cx, JSAtomMap *map, JSAtomList *al)
{
JSAtom **vector;
JSAtomListElement *ale, *next;
uint32 count;
ale = al->list;
if (!ale) {
map->vector = NULL;
map->length = 0;
return JS_TRUE;
}
count = al->count;
if (count >= ATOM_INDEX_LIMIT) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
JSMSG_TOO_MANY_LITERALS);
return JS_FALSE;
}
vector = JS_malloc(cx, (size_t) count * sizeof *vector);
if (!vector)
return JS_FALSE;
do {
vector[ale->index] = ale->atom;
next = ale->next;
ale->next = NULL;
} while ((ale = next) != NULL);
al->list = NULL;
al->count = 0;
map->vector = vector;
map->length = (jsatomid)count;
return JS_TRUE;
}
JS_FRIEND_API(void)
js_FreeAtomMap(JSContext *cx, JSAtomMap *map)
{
if (map->vector) {
free(map->vector);
map->vector = NULL;
}
map->length = 0;
}