void set_local_variable_table(OopDesc *value) {
obj_at_put(VAR_TABLE_INDEX, value);
}
ReturnOop
SymbolTable::symbol_for(TypeArray *byte_array, utf8 s, int len,
bool check_only JVM_TRAPS) {
if (byte_array == NULL) {
// If the source of the new symbol lives in the heap, you must
// GC-protect it by passing the source in a byte_array
GUARANTEE(!ObjectHeap::contains((OopDesc*)s), "must not be in heap");
}
if (unsigned(len) > 0xfff0) {
// Symbol's string length is a unsigned 16-bit number
Throw::out_of_memory_error(JVM_SINGLE_ARG_THROW_0);
}
const juint hash_value = hash(s, len);
if (UseROM) {
// The ROM symbol table's layout is different than that of the
// symbol table in heap. The main reason is to avoids holes in
// the table.
//
// **************************************************************
// WARNING: the value of ROM::symbol_table_num_buckets() is 1 off
// what you would think. Read the following carefully.
// **************************************************************
//
// Layout of the ROM symbol table with <n> buckets:
//
// (a) The first <n> elements are pointers to the start of the
// <n> buckets. Note that element <n> also marks the exclusive
// end of the <n-1> bucket.
// (b) One additional element is written at to mark the exclusive
// end of the very last bucket.
// (c) If RewriteROMConstantPool is disabled, the contents of
// bucket #0 starts here, followed by the contents of bucket #1,
// and so forth.
//
// For example, say we have two buckets; bucket #0 contains "foo";
// bucket #1 contains "bar" and "blah":
//
// symbol_table_size = 2;
// symbol_table[] = {
// &symbol_table[3]; // (a) start of bucket#0
// &symbol_table[4]; // (a) end of bucket#0/start of bucket#1
// &symbol_table[6]; // (b) end of bucket#1
// pointer to Symbol "foo"; // (c) item in bucket#0
// pointer to Symbol "bar"; // (c) item in bucket#1
// pointer to Symbol "blah"; // (c) item in bucket#1
// };
//
// Note that if RewriteROMConstantPool is enabled (the default),
// part (c) is actually stored inside the merged constant pool;
// parts (a) and (b) are written with special macros to point to
// the merged constant pool instead.
ReturnOop old_sym = ROM::symbol_for(s, hash_value, len);
if( old_sym ) {
return old_sym;
}
}
const juint mask = juint(length() - 1);
juint index = hash_value & mask;
const juint start = index;
SymbolDesc**base = (SymbolDesc**)base_address();
SymbolDesc* old;
if (0 < len && len <= 6) {
// Quicker search. This happens very frequently if a MIDlet is
// obfuscated -- many variables will have name length <= 6
//
// Note: this requires that the unused space in the SymbolDesc be filled
// with zeros.
union {
jushort shorts[4];
juint ints[2];
} blob;
blob.ints[0] = 0;
blob.ints[1] = 0;
blob.shorts[0] = (jushort)len;
jvm_memcpy(&blob.shorts[1], s, len);
const juint blob0 = blob.ints[0];
if( len <= 2 ) {
do {
old = base[index];
if( old == NULL ) break;
const juint *body = ((const juint*)old) + sizeof(OopDesc)/BytesPerWord;
if (blob0 == body[0]) {
return (ReturnOop)old;
}
index ++;
index &= mask;
// Do not rewrite as while( (index = (++index & mask)) != start );
// ADS compiler generates incorrect code.
} while( index != start );
} else {
const juint blob1 = blob.ints[1];
do {
old = base[index];
if( old == NULL ) break;
const juint *body = ((const juint*)old) + sizeof(OopDesc)/BytesPerWord;
if( blob0 == body[0] && blob1 == body[1] ) {
return (ReturnOop)old;
}
index ++;
index &= mask;
// Do not rewrite as while( (index = (++index & mask)) != start );
// ADS compiler generates incorrect code.
} while( index != start );
}
} else {
do {
old = base[index];
if( old == NULL ) break;
if( old->matches(s, len)) {
return (ReturnOop)old;
}
index ++;
index &= mask;
// Do not rewrite as while( (index = (++index & mask)) != start );
// ADS compiler generates incorrect code.
} while( index != start );
}
if (check_only) {
// The specified symbol is not found
return NULL;
} else {
if( old ) {
// We'd come to here if we're really out of memory
Throw::out_of_memory_error(JVM_SINGLE_ARG_THROW_0);
}
// Create a new Symbol of the specified value
UsingFastOops fast_oops;
Symbol::Fast new_symbol = Universe::new_symbol(byte_array, s, len
JVM_CHECK_0);
obj_at_put(index, &new_symbol);
int new_count = Task::current()->incr_symbol_table_count();
if (new_count > desired_max_symbol_count()) {
grow_and_replace_symbol_table();
}
return new_symbol.obj();
}
}
void set_line_number_table(OopDesc *value) {
obj_at_put(LINE_TABLE_INDEX, value);
}
