1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * version 2 for more details (a copy is included in the LICENSE file that
13  * accompanied this code).
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15  * You should have received a copy of the GNU General Public License version
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17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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24 
25 #include "precompiled.hpp"
26 #include "interpreter/bytecodeStream.hpp"
27 #include "interpreter/bytecodes.hpp"
28 #include "runtime/handles.inline.hpp"
29 
raw_next_special(Bytecodes::Code code)30 Bytecodes::Code RawBytecodeStream::raw_next_special(Bytecodes::Code code) {
31   assert(!is_last_bytecode(), "should have been checked");
32   // set next bytecode position
33   address bcp = RawBytecodeStream::bcp();
34   address end = method()->code_base() + end_bci();
35   int len = Bytecodes::raw_special_length_at(bcp, end);
36   // Very large tableswitch or lookupswitch size can cause _next_bci to overflow.
37   if (len <= 0 || (_bci > _end_bci - len) || (_bci - len >= _next_bci)) {
38     code = Bytecodes::_illegal;
39   } else {
40     _next_bci += len;
41     // set attributes
42     _is_wide = false;
43     // check for special (uncommon) cases
44     if (code == Bytecodes::_wide) {
45       if (bcp + 1 >= end) {
46         code = Bytecodes::_illegal;
47       } else {
48         code = (Bytecodes::Code)bcp[1];
49         _is_wide = true;
50       }
51     }
52   }
53   _raw_code = code;
54   return code;
55 }
56 
BaseBytecodeStream(const methodHandle & method)57 BaseBytecodeStream::BaseBytecodeStream(const methodHandle& method) : _method(method) {
58   set_interval(0, _method->code_size());
59   _is_raw = false;
60 }
61 
62 #ifdef ASSERT
assert_raw_index_size(int size) const63 void BaseBytecodeStream::assert_raw_index_size(int size) const {
64   if (raw_code() == Bytecodes::_invokedynamic && is_raw()) {
65     // in raw mode, pretend indy is "bJJ__"
66     assert(size == 2, "raw invokedynamic instruction has 2-byte index only");
67   } else {
68     bytecode().assert_index_size(size, raw_code(), is_wide());
69   }
70 }
71 
assert_raw_stream(bool want_raw) const72 void BaseBytecodeStream::assert_raw_stream(bool want_raw) const {
73   if (want_raw) {
74     assert( is_raw(), "this function only works on raw streams");
75   } else {
76     assert(!is_raw(), "this function only works on non-raw streams");
77   }
78 }
79 #endif //ASSERT
80