Horton

Re: JIT compiling with LLVM v10.0

Thomas Munro <thomas.munro@enterprisedb.com>

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From: Thomas Munro <thomas.munro@enterprisedb.com>
To: Andres Freund <andres@anarazel.de>
Cc: Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2018-02-07T22:50:17Z
Lists: pgsql-hackers 
On Thu, Feb 8, 2018 at 3:54 AM, Andres Freund <andres@anarazel.de> wrote:
> I've pushed v10.0. The big (and pretty painful to make) change is that
> now all the LLVM specific code lives in src/backend/jit/llvm, which is
> built as a shared library which is loaded on demand.
>
> The layout is now as follows:
>
> src/backend/jit/jit.c:
>     Part of JITing always linked into the server. Supports loading the
>     LLVM using JIT library.
>
> src/backend/jit/llvm/
> Infrastructure:
>  llvmjit.c:
>     General code generation and optimization infrastructure
>  llvmjit_error.cpp, llvmjit_wrap.cpp:
>     Error / backward compat wrappers
>  llvmjit_inline.cpp:
>     Cross module inlining support
> Code-Gen:
>   llvmjit_expr.c
>     Expression compilation
>   llvmjit_deform.c
>     Deform compilation

You are asking LLVM to dlopen(""), which doesn't work on my not-Linux,
explaining the errors I reported in the older thread.  The portable
way to dlopen the main binary is dlopen(NULL), so I think you need to
pass NULL in to LLVMLoadLibraryPermanently(), even though that isn't
really clear from any LLVM documentation I've looked at.

diff --git a/src/backend/jit/llvm/llvmjit.c b/src/backend/jit/llvm/llvmjit.c
index a1bc6449f7..874bddf81e 100644
--- a/src/backend/jit/llvm/llvmjit.c
+++ b/src/backend/jit/llvm/llvmjit.c
@@ -443,7 +443,7 @@ llvm_session_initialize(void)
        cpu = NULL;

        /* force symbols in main binary to be loaded */
-       LLVMLoadLibraryPermanently("");
+       LLVMLoadLibraryPermanently(NULL);

        llvm_opt0_orc = LLVMOrcCreateInstance(llvm_opt0_targetmachine);
        llvm_opt3_orc = LLVMOrcCreateInstance(llvm_opt3_targetmachine);

-- 
Thomas Munro
http://www.enterprisedb.com

Commits

  1. Improve JIT docs.

  2. Add documentation for the JIT feature.

  3. Add EXPLAIN support for JIT.

  4. Add inlining support to LLVM JIT provider.

  5. JIT tuple deforming in LLVM JIT provider.

  6. Add FIELDNO_* macro designating offset into structs required for JIT.

  7. Add expression compilation support to LLVM JIT provider.

  8. Expand list of synchronized types and functions in LLVM JIT provider.

  9. Add helpers for emitting LLVM IR.

  10. Basic planner and executor integration for JIT.

  11. Debugging and profiling support for LLVM JIT provider.

  12. Support for optimizing and emitting code in LLVM JIT provider.

  13. Add file containing extensions of the LLVM C API.

  14. Basic JIT provider and error handling infrastructure.

  15. Add configure infrastructure (--with-llvm) to enable LLVM support.

  16. Add C++ support to configure.

  17. Add PGAC_PROG_VARCC_VARFLAGS_OPT autoconf macro.

  18. Fix VM buffer pin management in heap_lock_updated_tuple_rec().

  19. Allow tupleslots to have a fixed tupledesc, use in executor nodes.

  20. Expression evaluation based aggregate transition invocation.

  21. Perform slot validity checks in a separate pass over expression.

  22. Rely on executor utils to build targetlist for DML RETURNING.

  23. Refer to OS X as "macOS", except for the port name which is still "darwin".