Skip to content

feat: support return type annotations for autodiff calls #1350

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Draft
wants to merge 2 commits into
base: main
Choose a base branch
from
Draft

feat: support return type annotations for autodiff calls #1350

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
14508ff
feat: support return type annotations for autodiff calls
avik-pal May 28, 2025
8a07ab4
test: return annotation with gradients
avik-pal May 29, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
20 changes: 17 additions & 3 deletions src/Enzyme.jl
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -243,6 +243,14 @@ function set_act!(inp, path, reverse, tostore; emptypath=false)
return nothing
end

function marked_const_along_path(res, path)
for p in path
res = traced_getfield(res, p)
res isa Enzyme.Const && return true
end
return res isa Enzyme.Const
end

function overload_autodiff(
::CMode, f::FA, ::Type{A}, args::Vararg{Enzyme.Annotation,Nargs}
) where {CMode<:Enzyme.Mode,FA<:Enzyme.Annotation,A<:Enzyme.Annotation,Nargs}
Expand Down Expand Up @@ -346,9 +354,15 @@ function overload_autodiff(
act = act_from_type(A, reverse, needs_primal(CMode))
push!(ret_activity, act)
if act == enzyme_out || act == enzyme_outnoneed
attr = MLIR.IR.DenseElementsAttribute(
fill(one(unwrapped_eltype(a)), size(a))
)
fill_value =
if marked_const_along_path(
result, TracedUtils.get_idx(a, resprefix)[2:end]
)
zero(unwrapped_eltype(a))
else
one(unwrapped_eltype(a))
end
attr = MLIR.IR.DenseElementsAttribute(fill(fill_value, size(a)))
cst = MLIR.IR.result(MLIR.Dialects.stablehlo.constant(; value=attr), 1)
push!(ad_inputs, cst)
end
Expand Down
20 changes: 20 additions & 0 deletions test/autodiff.jl
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -255,3 +255,23 @@ end
contains(repr(hlo), "stablehlo.rng_bit_generator")
end
end

function simple_grad_with_no_ret_annotation(x::AbstractArray{T}) where {T}
return sum(x; dims=1), sum(abs2, x)
end

function simple_grad_with_ret_annotation(x::AbstractArray{T}) where {T}
return Const(sum(x; dims=1)), sum(abs2, x)
end

@testset "return annotation" begin
x = Reactant.to_rarray(rand(Float32, 4, 4))

res1 = only(@jit(Enzyme.gradient(Reverse, simple_grad_with_no_ret_annotation, x)))

@test res1 ≈ (2 .* Array(x) .+ 1)

res2 = only(@jit(Enzyme.gradient(Reverse, simple_grad_with_ret_annotation, x)))

@test res2 ≈ (2 .* Array(x))
end
Loading