bytecodeStream.cpp

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#include"interpreter/bytecodeStream.hpp"
#include"interpreter/bytecodes.hpp"
#include"runtime/handles.inline.hpp"

Bytecodes::Code RawBytecodeStream::raw_next_special(Bytecodes::Code code) {
assert(!is_last_bytecode(), "should have been checked");
// set next bytecode position
 address bcp = RawBytecodeStream::bcp();
 address end = method()->code_base() + end_bci();
int len = Bytecodes::raw_special_length_at(bcp, end);
// Very large tableswitch or lookupswitch size can cause _next_bci to overflow.
if (len <= 0 || (_bci > _end_bci - len) || (_bci - len >= _next_bci)) {
 code = Bytecodes::_illegal;
 } else {
 _next_bci += len;
// set attributes
 _is_wide = false;
// check for special (uncommon) cases
if (code == Bytecodes::_wide) {
if (bcp + 1 >= end) {
 code = Bytecodes::_illegal;
 } else {
 code = (Bytecodes::Code)bcp[1];
 _is_wide = true;
 }
 }
 }
 _raw_code = code;
return code;
}

BaseBytecodeStream::BaseBytecodeStream(const methodHandle& method) : _method(method) {
set_interval(0, _method->code_size());
 _is_raw = false;
}

#ifdef ASSERT
voidBaseBytecodeStream::assert_raw_index_size(int size) const {
if (raw_code() == Bytecodes::_invokedynamic && is_raw()) {
// in raw mode, pretend indy is "bJJ__"
assert(size == 2, "raw invokedynamic instruction has 2-byte index only");
 } else {
bytecode().assert_index_size(size, raw_code(), is_wide());
 }
}

voidBaseBytecodeStream::assert_raw_stream(bool want_raw) const {
if (want_raw) {
assert( is_raw(), "this function only works on raw streams");
 } else {
assert(!is_raw(), "this function only works on non-raw streams");
 }
}
#endif//ASSERT