Expand Julia's atomic modify pseudo-intrinsic - #945
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From Julia 1.13, codegen emits atomic modifications (e.g. `@atomic x.f += 1`) as calls to `julia.atomicmodify`, which Julia's pipeline expands after GC lowering with `ExpandAtomicModifyPass` (JuliaLang/julia#57010). Our pipeline didn't, so the call survived and failed validation as a call to an unknown function.
vchuravy
approved these changes
Sep 24, 2026
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Since Julia 1.13 (JuliaLang/julia#57010), codegen emits atomic modifications such as
@atomic x.f += 1as calls to thejulia.atomicmodifypseudo-intrinsic, which Julia's own pipeline expands after GC lowering withExpandAtomicModifyPass. GPUCompiler builds its own GC-lowering pipeline and didn't run that pass, so the call survived into the final IR. For GPU targets, validation rejects that as a call to an unknown function:This PR adds the pass right after the GC lowering, as Julia does. The new native test fails on 1.13 without the fix and passes with it; on 1.12 and 1.10 it passes either way. With this change, Metal.jl's atomics tests (including an
@atomicfield modification in a kernel, from JuliaGPU/Metal.jl#977) pass on 1.13.