PrintAssembly at runtime / to different target

[Stefan Reich]

Oh, now it seems to work, thanks. It does print the assembly BOTH on STDOUT
and in the XML log file. What's this affiliation the JVM has with STDOUT? :D

~/dev/jdk-13-src/jdk13/build/linux-x86_64-server-fastdebug/jdk/bin/java \
  -XX:+UnlockDiagnosticVMOptions \
  -XX:+PrintAssembly -XX:PrintAssemblyOptions=intel \
  -XX:LogFile=the.log \
  -cp ../javacpp.jar:. Dot >hotspot-intel.out

On Tue, 17 Sep 2019 at 00:21, Vitaly Davidovich <vitalyd at gmail.com> wrote:

> What if you specify -XX:LogFile=/path/to/file? It should then send output
> there.
>
> On Mon, Sep 16, 2019 at 12:35 PM Stefan Reich <
> stefan.reich.maker.of.eye at googlemail.com> wrote:
>
>> Oops, too many lines copied, please ignore. This is the actual log:
>>
>> root at vmd41736:~/dev/ii-assembly# java13-dbg -version
>> openjdk version "13-internal" 2019-09-17
>> OpenJDK Runtime Environment (fastdebug build
>> 13-internal+0-adhoc.root.jdk13)
>> OpenJDK 64-Bit Server VM (fastdebug build 13-internal+0-adhoc.root.jdk13,
>> mixed mode)
>> root at vmd41736:~/dev/ii-assembly# java13-dbg
>> -XX:+UnlockDiagnosticVMOptions
>> -XX:+LogCompilation -XX:+PrintAssembly -jar ~/.javax/x30.jar -noawt
>> 1025248
>> >hotspot.out
>> OpenJDK 64-Bit Server VM warning: PrintAssembly is enabled; turning on
>> DebugNonSafepoints to gain additional output
>> WARNING: An illegal reflective access operation has occurred
>> WARNING: Illegal reflective access by x30 (file:/root/.javax/x30.jar) to
>> method java.lang.Object.registerNatives()
>> WARNING: Please consider reporting this to the maintainers of x30
>> WARNING: Use --illegal-access=warn to enable warnings of further illegal
>> reflective access operations
>> WARNING: All illegal access operations will be denied in a future release
>> root at vmd41736:~/dev/ii-assembly# ls -ltrh
>> total 184M
>> -rw-r--r-- 1 root root  42M Sep 16 18:26 hotspot.out
>> -rw-r--r-- 1 root root  46M Sep 16 18:26 hotspot_pid15548.log
>> root at vmd41736:~/dev/ii-assembly# grep mov hotspot.out
>> hotspot_pid15548.log|head -5
>> hotspot.out: ;; move 0 -> 2
>> hotspot.out:000     movl    rscratch1, [j_rarg0 +
>> oopDesc::klass_offset_in_bytes()]
>> # compressed klass
>> hotspot.out: movq    rscratch1, poll_offset[r15_thread]
>> #polling_page_address
>> hotspot.out:000     movl    rscratch1, [j_rarg0 +
>> oopDesc::klass_offset_in_bytes()]
>> # compressed klass
>> hotspot.out:02c     movsbl  R10, [RSI + #20 (8-bit)] # byte ! Field:
>> java/lang/String.coder (constant)
>>
>> On Mon, 16 Sep 2019 at 18:31, Stefan Reich <
>> stefan.reich.maker.of.eye at googlemail.com> wrote:
>>
>> > Hmm. I built JDK 13 from Mercurial with fastdebug, and it always sends
>> > assembly output to tty.
>> >
>> > root at vmd41736:~/dev/ii-assembly# java13-dbg -version
>> > openjdk version "13-internal" 2019-09-17
>> > OpenJDK Runtime Environment (fastdebug build
>> > 13-internal+0-adhoc.root.jdk13)
>> > OpenJDK 64-Bit Server VM (fastdebug build
>> 13-internal+0-adhoc.root.jdk13,
>> > mixed mode)
>> > root at vmd41736:~/dev/ii-assembly# java13-dbg
>> > -XX:+UnlockDiagnosticVMOptions -XX:+LogCompilation -XX:+PrintAssembly
>> -jar
>> > ~/.javax/x30.jar -noawt 1025248 >ii-assembly.out
>> > OpenJDK 64-Bit Server VM warning: PrintAssembly is enabled; turning on
>> > DebugNonSafepoints to gain additional output
>> > WARNING: An illegal reflective access operation has occurred
>> > WARNING: Illegal reflective access by x30 (file:/root/.javax/x30.jar) to
>> > method java.lang.Object.registerNatives()
>> > WARNING: Please consider reporting this to the maintainers of x30
>> > WARNING: Use --illegal-access=warn to enable warnings of further illegal
>> > reflective access operations
>> > WARNING: All illegal access operations will be denied in a future
>> release
>> > root at vmd41736:~/dev/ii-assembly# java13-dbg
>> > -XX:+UnlockDiagnosticVMOptions -XX:+LogCompilation -XX:+PrintAssembly
>> -jar
>> > ~/.javax/x30.jar -noawt 1025248 >hotspot.out
>> > OpenJDK 64-Bit Server VM warning: PrintAssembly is enabled; turning on
>> > DebugNonSafepoints to gain additional output
>> > WARNING: An illegal reflective access operation has occurred
>> > WARNING: Illegal reflective access by x30 (file:/root/.javax/x30.jar) to
>> > method java.lang.Object.registerNatives()
>> > WARNING: Please consider reporting this to the maintainers of x30
>> > WARNING: Use --illegal-access=warn to enable warnings of further illegal
>> > reflective access operations
>> > WARNING: All illegal access operations will be denied in a future
>> release
>> > root at vmd41736:~/dev/ii-assembly# ls -ltrh
>> > total 184M
>> > -rw-r--r-- 1 root root  42M Sep 16 18:26 hotspot.out
>> > -rw-r--r-- 1 root root  46M Sep 16 18:26 hotspot_pid15548.log
>> > root at vmd41736:~/dev/ii-assembly# grep mov hotspot.out
>> > hotspot_pid15548.log|head -5
>> > hotspot.out: ;; move 0 -> 2
>> > hotspot.out:000     movl    rscratch1, [j_rarg0 +
>> > oopDesc::klass_offset_in_bytes()] # compressed klass
>> > hotspot.out: movq    rscratch1, poll_offset[r15_thread]
>> > #polling_page_address
>> > hotspot.out:000     movl    rscratch1, [j_rarg0 +
>> > oopDesc::klass_offset_in_bytes()] # compressed klass
>> > hotspot.out:02c     movsbl  R10, [RSI + #20 (8-bit)] # byte ! Field:
>> > java/lang/String.coder (constant)
>> >
>> > On Mon, 16 Sep 2019 at 18:24, Aleksey Shipilev <shade at redhat.com>
>> wrote:
>> >
>> >> On 9/16/19 6:18 PM, Stefan Reich wrote:
>> >> > How can I get assembly output in hotspot.log though? I only ever see
>> it
>> >> on STDOUT, even with
>> >> > LogCompilation enabled.
>> >>
>> >> LogCompilation has to include output that would otherwise would end up
>> on
>> >> tty. It would be captured
>> >> in <tty> there.
>> >>
>> >> JMH -prof perfasm does use LogCompilation to get disassembly like this:
>> >>
>> >>
>> http://hg.openjdk.java.net/code-tools/jmh/file/99d7b73cf1e3/jmh-core/src/main/java/org/openjdk/jmh/profile/AbstractPerfAsmProfiler.java#l239
>> >>
>> >> --
>> >> Thanks,
>> >> -Aleksey
>> >>
>> >>
>> >
>> > --
>> > Stefan Reich
>> > BotCompany.de // Java-based operating systems
>> >
>>
>>
>> --
>> Stefan Reich
>> BotCompany.de // Java-based operating systems
>>
> --
> Sent from my phone
>


-- 
Stefan Reich
BotCompany.de // Java-based operating systems