JVM Java Virtual Machine and stacks -

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i have query interested in, full explanation though cannot find answers anywhere can explain me how jvm (java virtual machine) uses stacks , stack frames in order organise computations?

the java bytecode so-called stack-oriented programming language. model used lot of virtual machines - in contrast architecture of physical machines.

here example:

public static int foobar(int value) {     return value + 42; }

the java bytecode of method looks follows:

iload_0 bipush 42 iadd ireturn

these instructions not use registers. instead use stack computation:

  • push first argument onto stack.
  • push constant 42 onto stack.
  • pop 2 elements stack, add them , push result onto stack.
  • pop top element stack , return it.

it's same other java bytecode operations. there no registers can used. operations push and/or pop elements onto , stack.


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