Flux.jl/src/compiler/code.jl
2017-06-01 16:55:48 +01:00

95 lines
2.5 KiB
Julia

import DataFlow: cse
using MacroTools: @q
export @net
function graphdef(ex, params = [])
@capture(shortdef(ex), (args__,) -> body_)
body = @> body MacroTools.flatten liftloops graphm DataFlow.il
body = map(x -> x in params ? :(self.$x) : x, body)
return args, body
end
function makegraph(graph, args, params = [])
graph = prewalk(graph) do v
isconstant(v) && (i = findfirst(args, value(v[1]))) 0 ?
inputnode(i) :
v
end
graph = map(graph) do x
x isa Offset ?
:(Flux.Offset($(Expr(:quote, x.name)), $(x.n),
$(x.name in params ? :(self.$(x.name)) : x.name))) :
x
end
vertex(:(Flux.Frame(self)), graph)
end
function build_type(T, params)
@esc T
ex = quote
type $T <: Model
$(params...)
end
end
if any(x->isexpr(x, Symbol), params)
push!(ex.args,
:($T($(map(x->isexpr(x, Symbol) ? :($x::AArray) : x, params)...)) =
$T($(map(x->isexpr(x, Symbol) ? :(param($x)) : namify(x), params)...))))
end
ex
end
function deref_params(v)
map(v) do x
@capture(x, self.p_) ? :(Flux.state(self.$p)) : x
end
end
function build_forward(body, args)
iscyclic(body) && return :(error("Can't run forward pass on a cyclic graph"))
applylines(syntax(cse(deref_params(body))))
end
import Lazy: groupby
reifyparams(v::IVertex) = map(x -> x isa Param ? x.x : x, v)
# TODO: type hints for parameters
function process_type(ex)
@capture(ex, type T_ fs__ end)
@destruct [params = false || [],
funcs = true || []] = groupby(x->isexpr(x, :->, :function), fs)
@assert length(funcs) == 1
pnames = namify.(params)
args, body = graphdef(funcs[1], pnames)
self = esc(:self)
quote
$(build_type(T, params))
$(esc(:((self::$T)($(args...)) = $(build_forward(body, args)))))
$(esc(:(Flux.update!(self::$T, η)))) = ($(map(p -> :(update!($self.$p, η)), pnames)...);)
$(esc(:(Flux.graph(self::$T)))) = $(DataFlow.constructor(map(esc, makegraph(body, args, params))))
nothing
end
end
function process_anon(ex)
args, body = graphdef(ex)
:(Capacitor($(DataFlow.constructor(map(esc, makegraph(body, args)[1])))))
end
function process_def(ex)
# TODO: make a singleton net type
@capture(ex, f_(xs__) = body_)
:($(esc(f)) = @net $(esc(:(($(xs...),) -> $body))); nothing)
end
macro net(ex)
ex = shortdef(ex)
isexpr(ex, :type) ? process_type(ex) :
@capture(ex, (__,) -> _) ? process_anon(ex) :
@capture(ex, _(__) = _) ? process_def(ex) :
error("Unsupported model expression $ex")
end