|
| 1 | +module SciMLJacobianOperators |
| 2 | + |
| 3 | +using ADTypes: ADTypes |
| 4 | +using ConcreteStructs: @concrete |
| 5 | +using ConstructionBase: ConstructionBase |
| 6 | +using DifferentiationInterface: DifferentiationInterface |
| 7 | +using FastClosures: @closure |
| 8 | +using SciMLBase: SciMLBase, AbstractNonlinearProblem, AbstractNonlinearFunction |
| 9 | +using SciMLOperators: AbstractSciMLOperator |
| 10 | +using Setfield: @set! |
| 11 | + |
| 12 | +const DI = DifferentiationInterface |
| 13 | +const True = Val(true) |
| 14 | +const False = Val(false) |
| 15 | + |
| 16 | +abstract type AbstractMode end |
| 17 | + |
| 18 | +struct VJP <: AbstractMode end |
| 19 | +struct JVP <: AbstractMode end |
| 20 | + |
| 21 | +flip_mode(::VJP) = JVP() |
| 22 | +flip_mode(::JVP) = VJP() |
| 23 | + |
| 24 | +@concrete struct JacobianOperator{iip, T <: Real} <: AbstractSciMLOperator{T} |
| 25 | + mode <: AbstractMode |
| 26 | + |
| 27 | + jvp_op |
| 28 | + vjp_op |
| 29 | + |
| 30 | + size |
| 31 | + jvp_extras |
| 32 | + vjp_extras |
| 33 | +end |
| 34 | + |
| 35 | +function ConstructionBase.constructorof(::Type{<:JacobianOperator{iip, T}}) where {iip, T} |
| 36 | + return JacobianOperator{iip, T} |
| 37 | +end |
| 38 | + |
| 39 | +Base.size(J::JacobianOperator) = J.size |
| 40 | +Base.size(J::JacobianOperator, d::Integer) = J.size[d] |
| 41 | + |
| 42 | +for op in (:adjoint, :transpose) |
| 43 | + @eval function Base.$(op)(operator::JacobianOperator) |
| 44 | + @set! operator.mode = flip_mode(operator.mode) |
| 45 | + return operator |
| 46 | + end |
| 47 | +end |
| 48 | + |
| 49 | +function JacobianOperator(prob::AbstractNonlinearProblem, fu, u; jvp_autodiff = nothing, |
| 50 | + vjp_autodiff = nothing, skip_vjp::Val = False, skip_jvp::Val = False) |
| 51 | + @assert !(skip_vjp === True && skip_jvp === True) "Cannot skip both vjp and jvp \ |
| 52 | + construction." |
| 53 | + f = prob.f |
| 54 | + iip = SciMLBase.isinplace(prob) |
| 55 | + T = promote_type(eltype(u), eltype(fu)) |
| 56 | + fₚ = SciMLBase.JacobianWrapper{iip}(f, prob.p) |
| 57 | + |
| 58 | + vjp_op, vjp_extras = prepare_vjp(skip_vjp, prob, f, u, fu; autodiff = vjp_autodiff) |
| 59 | + jvp_op, jvp_extras = prepare_jvp(skip_jvp, prob, f, u, fu; autodiff = jvp_autodiff) |
| 60 | + |
| 61 | + return JacobianOperator{iip, T}( |
| 62 | + JVP(), jvp_op, vjp_op, (length(fu), length(u)), jvp_extras, vjp_extras) |
| 63 | +end |
| 64 | + |
| 65 | +prepare_vjp(::Val{true}, args...; kwargs...) = nothing, nothing |
| 66 | + |
| 67 | +function prepare_vjp(::Val{false}, prob::AbstractNonlinearProblem, |
| 68 | + f::AbstractNonlinearFunction, u::Number, fu::Number; autodiff = nothing) |
| 69 | + return prepare_scalar_op(Val(false), prob, f, u, fu; autodiff) |
| 70 | +end |
| 71 | + |
| 72 | +function prepare_vjp(::Val{false}, prob::AbstractNonlinearProblem, |
| 73 | + f::AbstractNonlinearFunction, u, fu; autodiff = nothing) |
| 74 | + SciMLBase.has_vjp(f) && return f.vjp, nothing |
| 75 | + |
| 76 | + if autodiff === nothing && SciMLBase.has_jac(f) |
| 77 | + if SciMLBase.isinplace(f) |
| 78 | + vjp_extras = (; jac_cache = similar(u, eltype(fu), length(fu), length(u))) |
| 79 | + vjp_op = @closure (vJ, v, u, p, extras) -> begin |
| 80 | + f.jac(extras.jac_cache, u, p) |
| 81 | + mul!(vec(vJ), extras.jac_cache', vec(v)) |
| 82 | + return |
| 83 | + end |
| 84 | + return vjp_op, vjp_extras |
| 85 | + else |
| 86 | + vjp_op = @closure (v, u, p, _) -> reshape(f.jac(u, p)' * vec(v), size(u)) |
| 87 | + return vjp_op, nothing |
| 88 | + end |
| 89 | + end |
| 90 | + |
| 91 | + @assert autodiff!==nothing "`vjp_autodiff` must be provided if `f` doesn't have \ |
| 92 | + analytic `vjp` or `jac`." |
| 93 | + |
| 94 | + if ADTypes.mode(autodiff) isa ADTypes.ForwardMode |
| 95 | + @warn "AD Backend: $(autodiff) is a Forward Mode backend. Computing VJPs using \ |
| 96 | + this will be slow!" |
| 97 | + end |
| 98 | + |
| 99 | + # TODO: Once DI supports const params we can use `p` |
| 100 | + fₚ = SciMLBase.JacobianWrapper{SciMLBase.isinplace(f)}(f, prob.p) |
| 101 | + if SciMLBase.isinplace(f) |
| 102 | + fu_cache = copy(fu) |
| 103 | + v_fake = copy(fu) |
| 104 | + di_extras = DI.prepare_pullback(fₚ, fu_cache, autodiff, u, v_fake) |
| 105 | + vjp_op = @closure (vJ, v, u, p, extras) -> begin |
| 106 | + DI.pullback!( |
| 107 | + fₚ, extras.fu_cache, reshape(vJ, size(u)), autodiff, u, v, extras.di_extras) |
| 108 | + end |
| 109 | + return vjp_op, (; di_extras, fu_cache) |
| 110 | + else |
| 111 | + di_extras = DI.prepare_pullback(f, autodiff, u, fu) |
| 112 | + vjp_op = @closure (v, u, p, extras) -> begin |
| 113 | + return DI.pullback(f, autodiff, u, v, extras.di_extras) |
| 114 | + end |
| 115 | + return vjp_op, (; di_extras) |
| 116 | + end |
| 117 | +end |
| 118 | + |
| 119 | +prepare_jvp(skip::Val{true}, args...; kwargs...) = nothing, nothing |
| 120 | + |
| 121 | +function prepare_jvp(::Val{false}, prob::AbstractNonlinearProblem, |
| 122 | + f::AbstractNonlinearFunction, u::Number, fu::Number; autodiff = nothing) |
| 123 | + return prepare_scalar_op(Val(false), prob, f, u, fu; autodiff) |
| 124 | +end |
| 125 | + |
| 126 | +function prepare_jvp(::Val{false}, prob::AbstractNonlinearProblem, |
| 127 | + f::AbstractNonlinearFunction, u, fu; autodiff = nothing) |
| 128 | + SciMLBase.has_vjp(f) && return f.vjp, nothing |
| 129 | + |
| 130 | + if autodiff === nothing && SciMLBase.has_jac(f) |
| 131 | + if SciMLBase.isinplace(f) |
| 132 | + jvp_extras = (; jac_cache = similar(u, eltype(fu), length(fu), length(u))) |
| 133 | + jvp_op = @closure (Jv, v, u, p, extras) -> begin |
| 134 | + f.jac(extras.jac_cache, u, p) |
| 135 | + mul!(vec(Jv), extras.jac_cache, vec(v)) |
| 136 | + return |
| 137 | + end |
| 138 | + return jvp_op, jvp_extras |
| 139 | + else |
| 140 | + jvp_op = @closure (v, u, p, _) -> reshape(f.jac(u, p) * vec(v), size(u)) |
| 141 | + return jvp_op, nothing |
| 142 | + end |
| 143 | + end |
| 144 | + |
| 145 | + @assert autodiff!==nothing "`jvp_autodiff` must be provided if `f` doesn't have \ |
| 146 | + analytic `vjp` or `jac`." |
| 147 | + |
| 148 | + if ADTypes.mode(autodiff) isa ADTypes.ReverseMode |
| 149 | + @warn "AD Backend: $(autodiff) is a Reverse Mode backend. Computing JVPs using \ |
| 150 | + this will be slow!" |
| 151 | + end |
| 152 | + |
| 153 | + # TODO: Once DI supports const params we can use `p` |
| 154 | + fₚ = SciMLBase.JacobianWrapper{SciMLBase.isinplace(f)}(f, prob.p) |
| 155 | + if SciMLBase.isinplace(f) |
| 156 | + fu_cache = copy(fu) |
| 157 | + di_extras = DI.prepare_pushforward(fₚ, fu_cache, autodiff, u, u) |
| 158 | + jvp_op = @closure (Jv, v, u, p, extras) -> begin |
| 159 | + DI.pushforward!(fₚ, extras.fu_cache, reshape(Jv, size(extras.fu_cache)), |
| 160 | + autodiff, u, v, extras.di_extras) |
| 161 | + end |
| 162 | + return jvp_op, (; di_extras, fu_cache) |
| 163 | + else |
| 164 | + di_extras = DI.prepare_pushforward(f, autodiff, u, u) |
| 165 | + jvp_op = @closure (v, u, p, extras) -> begin |
| 166 | + return DI.pushforward(f, autodiff, u, v, extras.di_extras) |
| 167 | + end |
| 168 | + return jvp_op, (; di_extras) |
| 169 | + end |
| 170 | +end |
| 171 | + |
| 172 | +function prepare_scalar_op(::Val{false}, prob::AbstractNonlinearProblem, |
| 173 | + f::AbstractNonlinearFunction, u::Number, fu::Number; autodiff = nothing) |
| 174 | + SciMLBase.has_vjp(f) && return f.vjp, nothing |
| 175 | + SciMLBase.has_jvp(f) && return f.jvp, nothing |
| 176 | + SciMLBase.has_jac(f) && return @closure((v, u, p, _)->f.jac(u, p) * v), nothing |
| 177 | + |
| 178 | + @assert autodiff!==nothing "`autodiff` must be provided if `f` doesn't have \ |
| 179 | + analytic `vjp` or `jvp` or `jac`." |
| 180 | + # TODO: Once DI supports const params we can use `p` |
| 181 | + fₚ = Base.Fix2(f, prob.p) |
| 182 | + di_extras = DI.prepare_derivative(fₚ, autodiff, u) |
| 183 | + op = @closure (v, u, p, extras) -> begin |
| 184 | + return DI.derivative(fₚ, autodiff, u, extras.di_extras) * v |
| 185 | + end |
| 186 | + return op, (; di_extras) |
| 187 | +end |
| 188 | + |
| 189 | +function VecJacOperator(args...; autodiff = nothing, kwargs...) |
| 190 | + return JacobianOperator(args...; kwargs..., skip_jvp = True, vjp_autodiff = autodiff)' |
| 191 | +end |
| 192 | + |
| 193 | +function JacVecOperator(args...; autodiff = nothing, kwargs...) |
| 194 | + return JacobianOperator(args...; kwargs..., skip_vjp = True, jvp_autodiff = autodiff) |
| 195 | +end |
| 196 | + |
| 197 | +export JacobianOperator, VecJacOperator, JacVecOperator |
| 198 | + |
| 199 | +end |
0 commit comments