archive/jdk
1
0
Fork 0
mirror of https://github.com/openjdk/jdk.git synced 2025-08-26 14:24:46 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

6833129: specjvm98 fails with NullPointerException in the compiler with -XX:DeoptimizeALot

Browse source 
Developed a reexecute logic for the interpreter to reexecute the bytecode when deopt happens

Reviewed-by: kvn, never, jrose, twisti
This commit is contained in:
Changpeng Fang 2009-07-31 17:12:33 -07:00
parent f2ea22a547
commit ae00753bf7
29 changed files with 465 additions and 241 deletions
Download patch file Download diff file Expand all files Collapse all files

45
hotspot/src/share/vm/interpreter/templateInterpreter.cpp
View file

@ -605,28 +605,41 @@ void TemplateInterpreter::ignore_safepoints() {
}
}
// If deoptimization happens, this method returns the point where to continue in
// interpreter. For calls (invokexxxx, newxxxx) the continuation is at next
// bci and the top of stack is in eax/edx/FPU tos.
// For putfield/getfield, put/getstatic, the continuation is at the same
// bci and the TOS is on stack.
//------------------------------------------------------------------------------------------------------------------------
// Deoptimization support
// Note: deopt_entry(type, 0) means reexecute bytecode
// deopt_entry(type, length) means continue at next bytecode
// If deoptimization happens, this function returns the point of next bytecode to continue execution
address TemplateInterpreter::deopt_continue_after_entry(methodOop method, address bcp, int callee_parameters, bool is_top_frame) {
return AbstractInterpreter::deopt_continue_after_entry(method, bcp, callee_parameters, is_top_frame);
}
address TemplateInterpreter::continuation_for(methodOop method, address bcp, int callee_parameters, bool is_top_frame, bool& use_next_mdp) {
// If deoptimization happens, this function returns the point where the interpreter reexecutes
// the bytecode.
// Note: Bytecodes::_athrow (C1 only) and Bytecodes::_return are the special cases
// that do not return "Interpreter::deopt_entry(vtos, 0)"
address TemplateInterpreter::deopt_reexecute_entry(methodOop method, address bcp) {
assert(method->contains(bcp), "just checkin'");
Bytecodes::Code code = Bytecodes::java_code_at(bcp);
if (code == Bytecodes::_return) {
// This is used for deopt during registration of finalizers
// during Object.<init>. We simply need to resume execution at
// the standard return vtos bytecode to pop the frame normally.
// reexecuting the real bytecode would cause double registration
// of the finalizable object.
assert(is_top_frame, "must be on top");
return _normal_table.entry(Bytecodes::_return).entry(vtos);
// This is used for deopt during registration of finalizers
// during Object.<init>. We simply need to resume execution at
// the standard return vtos bytecode to pop the frame normally.
// reexecuting the real bytecode would cause double registration
// of the finalizable object.
return _normal_table.entry(Bytecodes::_return).entry(vtos);
} else {
return AbstractInterpreter::continuation_for(method, bcp, callee_parameters, is_top_frame, use_next_mdp);
return AbstractInterpreter::deopt_reexecute_entry(method, bcp);
}
}
// If deoptimization happens, the interpreter should reexecute this bytecode.
// This function mainly helps the compilers to set up the reexecute bit.
bool TemplateInterpreter::bytecode_should_reexecute(Bytecodes::Code code) {
if (code == Bytecodes::_return) {
//Yes, we consider Bytecodes::_return as a special case of reexecution
return true;
} else {
return AbstractInterpreter::bytecode_should_reexecute(code);
}
}