On Wed, 13 Oct 2021 00:00:22 GMT, Magnus Ihse Bursie <i...@openjdk.org> wrote:
> This patch expands the newly added system for hsdis backends to include LLVM. > > The actual code in hsdis-llvm.cpp is based heavily on the work by @luhenry, > as published in the never integrated PR > https://github.com/openjdk/jdk/pull/392. (I have basically just ripped out > the binutils-based part of it.) > > Unfortunately I have not been able to make this work properly on Windows. > With some additional flags I made it compile without complaints, but it > caused hotspot to segfault in `LoadLibrary` (!) in `os::dll_load` when I > tried to load the library. This is somewhat ironic, since the initial > implementation was created by Ludovic for the very purpose of using it on > Windows. > > The lack of Windows support in this patch does not mean it is impossible to > get it to work, just that I need to co-operate with someone who has more > experience of compiling LLVM on Windows, and/or are more eager to get this > combination to work. On 10/16/21 09:13, Magnus Ihse Bursie wrote: > @theRealAph We should not push broken code, and we should not break the > existing build of hsdis. I fully agree with this. I will not push this patch > until all reviewers are happy, so you don't need to worry about that. :) > > My initial plan was to get the unix platforms working in this push, and > tackle Windows later on, but it seems now that it's better to keep this PR > around for a bit longer instead, and fold Windows support into it as well. > (Which means I'll wait for Monica to return and being able to test and help > out.) > > I need to understand better why things are failing for you. Can you describe > a reproducer? Sure. Create a .hotspot_compiler file containing print java.lang.String::checkIndex then ./build/macosx-aarch64-server-fastdebug/jdk/bin/java -XX:+PrintAssembly -version GNU disassembly of java.lang.String::isLatin1 prints in full, ending thusly [Exception Handler] 0x000000010a72c340: mov x19, #0xdead // #57005 ; {no_reloc} 0x000000010a72c344: mov x2, #0xa // #10 0x000000010a72c348: mov x4, #0xdead // #57005 0x000000010a72c34c: mov x5, #0xdead // #57005 0x000000010a72c350: adrp x8, 0x000000010a1c3000 ; {runtime_call handle_exception_from_callee Runtime1 stub} 0x000000010a72c354: add x8, x8, #0x1c0 0x000000010a72c358: blr x8 0x000000010a72c35c: dcps1 #0xdeae 0x000000010a72c360: .inst 0x0995f68e ; undefined 0x000000010a72c364: udf #1 [Deopt Handler Code] 0x000000010a72c368: adr x30, 0x000000010a72c368 0x000000010a72c36c: adrp x8, 0x000000010a26c000 ; {runtime_call DeoptimizationBlob} 0x000000010a72c370: add x8, x8, #0xbc0 0x000000010a72c374: br x8 -------------------------------------------------------------------------------- LLVM disassembly dies at [Exception Handler] 0x000000010672c340: mov x19, #0xdead ; {no_reloc} 0x000000010672c344: mov x2, #0xa 0x000000010672c348: mov x4, #0xdead 0x000000010672c34c: mov x5, #0xdead 0x000000010672c350: adrp x8, #-5672960 ; {runtime_call handle_exception_from_callee Runtime1 stub} 0x000000010672c354: add x8, x8, #0x1c0 0x000000010672c358: blr x8 0x000000010672c35c: dcps1 #0xdeae 0x000000010672c360: -------------------------------------------------------------------------------- This is llvm 12.0.1 from homebrew. ------------- PR: https://git.openjdk.java.net/jdk/pull/5920
