jvm 第5章 jvm 指令集和解释器

jvm 第5章 jvm 指令集和解释器

1，https://github.com/zxh0/jvmgo-book提供的源代码

package main import "fmt" import "jvmgo/ch05/classfile" import "jvmgo/ch05/instructions" import "jvmgo/ch05/instructions/base" import "jvmgo/ch05/rtda" func interpret(methodInfo *classfile.MemberInfo) { codeAttr := methodInfo.CodeAttribute() maxLocals := codeAttr.MaxLocals() maxStack := codeAttr.MaxStack() bytecode := codeAttr.Code() fmt.Printf("IMF code: %v\n",bytecode) thread := rtda.NewThread() frame := thread.NewFrame(maxLocals, maxStack) thread.PushFrame(frame) defer catchErr(frame) loop(thread, bytecode) } func catchErr(frame *rtda.Frame) { if r := recover(); r != nil { fmt.Printf("LocalVars:%v\n", frame.LocalVars()) fmt.Printf("OperandStack:%v\n", frame.OperandStack()) panic(r) } } func loop(thread *rtda.Thread, bytecode []byte) { frame := thread.PopFrame() reader := &base.BytecodeReader{} for { pc := frame.NextPC() thread.SetPC(pc) // decode reader.Reset(bytecode, pc) opcode := reader.ReadUint8() fmt.Printf("IMF opcode: %v\n",opcode) inst := instructions.NewInstruction(opcode) inst.FetchOperands(reader) frame.SetNextPC(reader.PC()) // execute fmt.Printf("pc:%2d inst:%T %v\n", pc, inst, inst) inst.Execute(frame) } }

2，写一个简单的java代码

package jvmgo.book.ch05; public class Ch05addTest {          public static void main(String[] args) {         int sum = 0;         for (int i = 1; i