Introspection and Reflection

AMDGPU.jl mirrors Julia's code_* reflection tools for GPU kernels, letting you inspect what a kernel lowers to at each compilation stage. This is the main way to debug performance and codegen issues — for example checking that a kernel stays type-stable or that a hot loop vectorizes.

Each @device_code_* macro wraps a kernel launch (@roc ...) and prints the corresponding representation instead of running it:

@device_code_lowered — lowered Julia IR.
@device_code_typed — type-inferred Julia IR (use this to spot type instabilities).
@device_code_warntype — type-inferred IR with instabilities highlighted.
@device_code_llvm — the generated LLVM IR.
@device_code_gcn — the final AMD GCN assembly.
@device_code — dump all of the above into a directory.

julia

using AMDGPU

function vadd!(c, a, b)
    i = workitemIdx().x
    c[i] = a[i] + b[i]
    return
end

a = AMDGPU.ones(Float32, 16); b = AMDGPU.ones(Float32, 16); c = similar(a)

@device_code_warntype @roc groupsize=16 vadd!(c, a, b)

The non-macro forms (AMDGPU.code_typed, AMDGPU.code_llvm, AMDGPU.code_gcn, …) take a function and a tuple of argument types directly, mirroring Base.code_typed and friends. These reflection tools are inherited from GPUCompiler.jl; see its documentation for the full set of options each macro accepts.

Introspection and Reflection ​

Introspection and Reflection