Re: JIT compiling with LLVM v12.2 - Mailing list pgsql-hackers

Hi,

On 2018-03-22 16:09:51 +1300, Thomas Munro wrote:
> On Thu, Mar 22, 2018 at 1:36 PM, Thomas Munro
> <thomas.munro@enterprisedb.com> wrote:
> > I've now run out of things to complain about for now.  Nice work!
> 
> I jumped on a POWER8 box.  As expected, the same breakage occurs.  So
> I hacked LLVM 6.0 thusly:
> 
> diff --git a/lib/ExecutionEngine/Orc/IndirectionUtils.cpp
> b/lib/ExecutionEngine/Orc/IndirectionUtils.cpp
> index 68397be..08aa3a8 100644
> --- a/lib/ExecutionEngine/Orc/IndirectionUtils.cpp
> +++ b/lib/ExecutionEngine/Orc/IndirectionUtils.cpp
> @@ -54,7 +54,11 @@ createLocalCompileCallbackManager(const Triple &T,
>  std::function<std::unique_ptr<IndirectStubsManager>()>
>  createLocalIndirectStubsManagerBuilder(const Triple &T) {
>    switch (T.getArch()) {
> -    default: return nullptr;
> +    default:
> +      return [](){
> +        return llvm::make_unique<
> +                       orc::LocalIndirectStubsManager<orc::OrcGenericABI>>();
> +      };
> 
>      case Triple::aarch64:
>        return [](){

> I am not qualified to have an opinion on whether this is the correct
> fix for LLVM, but with this change our make check passes, indicating
> that things are otherwise looking good on this architecture.

Yea, that should do the trick, as long as one doesn't rely on indirect
stubs, which we don't.  Kinda wonder if we could hackfix this by putting
your definition of createLocalIndirectStubsManagerBuilder() into
something earlier on the search path...


> So I've now tested your branch on various combinations of:
> FreeBSD/amd64 (including with a weird CPU that lacks AVX),
> Debian/amd64, Debian/i386, Debian/arm64, RHEL/ppc64le, macOS/amd64,
> with LLVM 3.9, 4,0, 5.0, 6.0, with GCC and clang as the main compiler,
> with libstdc++ and libc++ as the C++ standard library.

Many thanks again.


> If I had access to one I'd try it on a big endian machine, but I
> don't.  Anyone?  The elephant in the room is Windows.  I'm not
> personally in the same room as that particular elephant, however.

Hah.  I'm not 100% sure I can MSVC project stuff done for this release,
TBH. Doing it via mingw shouldn't be much trouble. But I'm aiming for
fixing the project generation support too.


> FWIW, your branch doesn't build against LLVM master (future 7.0),
> because the shared module stuff is changing:
> 
> llvmjit.c: In function ‘llvm_compile_module’:
> llvmjit.c:544:4: error: unknown type name ‘LLVMSharedModuleRef’
>     LLVMSharedModuleRef smod;
>     ^
> llvmjit.c:546:4: warning: implicit declaration of function
> ‘LLVMOrcMakeSharedModule’ [-Wimplicit-function-declaration]
>     smod = LLVMOrcMakeSharedModule(context->module);
>     ^
> llvmjit.c:548:12: warning: passing argument 3 of
> ‘LLVMOrcAddEagerlyCompiledIR’ makes pointer from integer without a
> cast [enabled by default]
>             llvm_resolve_symbol, NULL))
>             ^
> In file included from llvmjit.c:31:0:
> /home/thomas.munro/build/llvm/debug/install/include/llvm-c/OrcBindings.h:99:1:
> note: expected ‘LLVMModuleRef’ but argument is of type ‘int’
>  LLVMOrcAddEagerlyCompiledIR(LLVMOrcJITStackRef JITStack,
>  ^
> llvmjit.c:552:4: warning: implicit declaration of function
> ‘LLVMOrcDisposeSharedModuleRef’ [-Wimplicit-function-declaration]
>     LLVMOrcDisposeSharedModuleRef(smod);

Yea, I guess we could add branches for that, but 7 just branched and is
a moving target, so I'm inclined to wait a bit.

Greetings,

Andres Freund