JVM PC计数器和堆栈空间如何与JIT一起使用？

Question

When a Java method get JIT-compiled and start running the JIT-ed native code:

1. Is the stack space still the same with previous one which running in interpreter mode?
2. Does the PC counter still being updated when running in JIT mode? if so, how?

(Let's say we are using OpenJDK).

Answer 1

Is the stack space still the same with previous one which running in interpreter mode?

The call stack is the same. It doesn't rebuild the stack when JIT-ed code is swapped in.

The value stack however can be assigned to registers and thus not maintained in native code.

Does the PC counter still being updated when running in JIT mode? if so, how?

The CPU's PC counter is used in native mode. The virtual registers are notional in native optimised code.