1、下载hsdis-amd64.dylib工具
链接: https://pan.baidu.com/s/1Qpww4ysxMQXgdekiSuxdIA 密码: 1jva
2、将hsdis-amd64.dylib放到Jdk对应文件夹中
将工具放到
…/jdk1.8.0_181.jdk/Contents/Home/jre/lib/server/
3、使用hsdis-amd64.dylib工具
通过在执行java命令的时候增加配置参数,执行java文件的同时输出其汇编代码。
参数为:-server -Xcomp -XX:+UnlockDiagnosticVMOptions -XX:+PrintAssembly -XX:CompileCommand=compileonly
以代码V.java为例
public class V {
private static volatile int a_value;
public static void a_test(){
a_value = 1;
}
public static void main(String[] args) {
a_test();
System.out.println("aaaaa");
}
}
方法一 命令行执行
java -server -Xcomp -XX:+UnlockDiagnosticVMOptions -XX:+PrintAssembly -XX:CompileCommand=compileonly …/V.java
除了输出aaaaa外,还输出了汇编代码,代码非常多就是了。
如果觉得代码太多,可以针对某个方法进行汇编代码的输出。在XX:CompileCommand=compileonly后增加对应方法即可。
例如:… XX:CompileCommand=compileonly,*V.a_test()
该操作我没做命令行试过,我都是在ide里边配置的。
aaaaa
server jjleong$ java -server -Xcomp -XX:+UnlockDiagnosticVMOptions -XX:+PrintAssembly -XX:CompileCommand=compileonly .../V.java
Java HotSpot(TM) 64-Bit Server VM warning: PrintAssembly is enabled; turning on DebugNonSafepoints to gain additional output
CompileCommand: An error occurred during parsing
Line: compileonly
Error: Could not parse method pattern
Usage: '-XX:CompileCommand=command,"package/Class.method()"'
Use: '-XX:CompileCommand=help' for more information.
Compiled method (c1) 22 1 3 java.lang.invoke.MethodHandle::<clinit> (30 bytes)
total in heap [0x000000011a7cf010,0x000000011a7cf860] = 2128
relocation [0x000000011a7cf188,0x000000011a7cf208] = 128
main code [0x000000011a7cf220,0x000000011a7cf5a0] = 896
stub code [0x000000011a7cf5a0,0x000000011a7cf658] = 184
oops [0x000000011a7cf658,0x000000011a7cf668] = 16
metadata [0x000000011a7cf668,0x000000011a7cf678] = 16
scopes data [0x000000011a7cf678,0x000000011a7cf6f0] = 120
scopes pcs [0x000000011a7cf6f0,0x000000011a7cf840] = 336
dependencies [0x000000011a7cf840,0x000000011a7cf848] = 8
nul chk table [0x000000011a7cf848,0x000000011a7cf860] = 24
Loaded disassembler from hsdis-amd64.dylib
----------------------------------------------------------------------
java/lang/invoke/MethodHandle.<clinit>()V [0x000000011a7cf220, 0x000000011a7cf658] 1080 bytes
[Disassembling for mach='i386:x86-64']
[Entry Point]
[Verified Entry Point]
[Constants]
# {method} {0x00000008000a7400} '<clinit>' '()V' in 'java/lang/invoke/MethodHandle'
# [sp+0x60] (sp of caller)
0x000000011a7cf220: mov %eax,-0x14000(%rsp)
0x000000011a7cf227: push %rbp
0x000000011a7cf228: sub $0x50,%rsp
0x000000011a7cf22c: movabs $0x133245bf0,%rsi ; {metadata(method data for {method} {0x00000008000a7400} '<clinit>' '()V' in 'java/lang/invoke/MethodHandle')}
0x000000011a7cf236: mov 0x104(%rsi),%edi
0x000000011a7cf23c: add $0x8,%edi
0x000000011a7cf23f: mov %edi,0x104(%rsi)
0x000000011a7cf245: jmpq 0x000000011a7cf3ae ;*ldc {reexecute=0 rethrow=0 return_oop=0}
; - java.lang.invoke.MethodHandle::<clinit>@0 (line 440)
0x000000011a7cf24a: movabs $0x7bfe2fd18,%rsi ; {oop(a 'java/lang/Class'{0x00000007bfe2fd18} = 'java/lang/invoke/MethodHandle')}
0x000000011a7cf254: mov %rsi,%rdi
0x000000011a7cf257: movabs $0x133245bf0,%rbx ; {metadata(method data for {method} {0x00000008000a7400} '<clinit>' '()V' in 'java/lang/invoke/MethodHandle')}
0x000000011a7cf261: addq $0x1,0x140(%rbx)
0x000000011a7cf269: nopw 0x0(%rax,%rax,1)
0x000000011a7cf26f: callq 0x000000011a265900 ; ImmutableOopMap{}
;*invokevirtual desiredAssertionStatus {reexecute=0 rethrow=0 return_oop=0}
; - java.lang.invoke.MethodHandle::<clinit>@2 (line 440)
; {optimized virtual_call}
0x000000011a7cf274: cmp $0x0,%eax
0x000000011a7cf277: movabs $0x133245bf0,%rdx ; {metadata(method data for {method} {0x00000008000a7400} '<clinit>' '()V' in 'java/lang/invoke/MethodHandle')}
0x000000011a7cf281: movabs $0x178,%rcx
0x000000011a7cf28b: jne 0x000000011a7cf29b
0x000000011a7cf291: movabs $0x188,%rcx
0x000000011a7cf29b: mov (%rdx,%rcx,1),%rsi
0x000000011a7cf29f: lea 0x1(%rsi),%rsi
...
方法二 ide执行
以android studio为例,在Run Config里边配置VM options即可