jit: Stop emitting lifetime.end for LLVM 22.

Thomas Munro <tmunro@postgresql.org>

Commit: c00ea2b5b4f16496d0f8545266af0b9945e54800
Author: Thomas Munro <tmunro@postgresql.org>
Date: 2026-04-02T02:55:21Z
Releases: 15.18
jit: Stop emitting lifetime.end for LLVM 22.

The lifetime.end intrinsic can now only be used for stack memory
allocated with alloca[1][2][3].  We use it to tell LLVM about the
lifetime of function arguments/isnull values that we keep in palloc'd
memory, so that it can avoid spilling registers to memory.

We might need to rearrange things and put them on the stack, but that'll
take some research.  In the meantime, unbreak the build on LLVM 22.

[1] https://github.com/llvm/llvm-project/pull/149310
[2] https://llvm.org/docs/LangRef.html#llvm-lifetime-end-intrinsic
[3] https://llvm.org/docs/LangRef.html#i-alloca

Backpatch-through: 14
Reviewed-by: Matheus Alcantara <matheusssilv97@gmail.com> (earlier attempt)
Reviewed-by: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com> (earlier attempt)
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier attempt)
Discussion: https://postgr.es/m/CA%2BhUKGJTumad75o8Zao-LFseEbt%3DenbUFCM7LZVV%3Dc8yg2i7dg%40mail.gmail.com

Files

PathChange+/−
src/backend/jit/llvm/llvmjit_expr.c modified +8 −3

Discussion

  • LLVM 22 21 messages · 2026-01-03 → 2026-04-03