Add strong zero getters (#2427)

* Add strong zero getters

* more

* fix

* fix

* fix

* fix

* fix

* e2

* fixup

Author: wsmoses

Project.toml

@@ -1,7 +1,7 @@
 name = "Enzyme"
 uuid = "7da242da-08ed-463a-9acd-ee780be4f1d9"
 authors = ["William Moses <wmoses@mit.edu>", "Valentin Churavy <vchuravy@mit.edu>"]
-version = "0.13.47"
+version = "0.13.48"
 
 [deps]
 CEnum = "fa961155-64e5-5f13-b03f-caf6b980ea82"
@@ -39,7 +39,7 @@ EnzymeStaticArraysExt = "StaticArrays"
 BFloat16s = "0.2, 0.3, 0.4, 0.5"
 CEnum = "0.4, 0.5"
 ChainRulesCore = "1"
-EnzymeCore = "0.8.10"
+EnzymeCore = "0.8.11"
 Enzyme_jll = "0.0.181"
 GPUArraysCore = "0.1.6, 0.2"
 GPUCompiler = "1.3"

lib/EnzymeCore/Project.toml

@@ -1,7 +1,7 @@
 name = "EnzymeCore"
 uuid = "f151be2c-9106-41f4-ab19-57ee4f262869"
 authors = ["William Moses <wmoses@mit.edu>", "Valentin Churavy <vchuravy@mit.edu>"]
-version = "0.8.10"
+version = "0.8.11"
 
 [compat]
 Adapt = "3, 4"

lib/EnzymeCore/src/EnzymeCore.jl

@@ -258,7 +258,7 @@ Abstract type for which differentiation mode will be used.
 - `ABI`: what runtime [`ABI`](@ref) to use
 - `ErrIfFuncWritten`: whether to error when the function differentiated is a closure and written to.
 - `RuntimeActivity`: whether to enable runtime activity (default off). Runtime Activity is required is the differentiability of all mutable variables cannot be determined statically. For a deeper explanation see the [FAQ](@ref faq-runtime-activity)
-- `StrongZero`: whether to enforce that propagating a zero derivative input always ends up in zero derivative outputs. This is required to avoid nan's if one of the arguments may be infinite or nan. For a deeper explanation see the [FAQ](@ref faq-runtime-activity)
+- `StrongZero`: whether to enforce that propagating a zero derivative input always ends up in zero derivative outputs. This is required to avoid nan's if one of the arguments may be infinite or nan. For a deeper explanation see the [FAQ](@ref faq-strong-zero)
 
 !!! warning
     The type parameters of `Mode` are not part of the public API and can change without notice.
@@ -271,6 +271,24 @@ Abstract type for which differentiation mode will be used.
 """
 abstract type Mode{ABI, ErrIfFuncWritten, RuntimeActivity, StrongZero} end
 
+"""
+    runtime_activity(::Mode)
+    strong_zero(::Type{<:Mode})
+
+Returns whether the given mode has runtime activity set. For a deeper explanation of what strong zero is see the [FAQ](@ref faq-runtime-activity)
+"""
+runtime_activity(::Mode{<:Any, <:Any, RuntimeActivity}) where RuntimeActivity = RuntimeActivity
+runtime_activity(::Type{<:Mode{<:Any, <:Any, RuntimeActivity}}) where RuntimeActivity = RuntimeActivity
+
+"""
+    strong_zero(::Mode)
+    strong_zero(::Type{<:Mode})
+
+Returns whether the given mode has strong zero set. For a deeper explanation of what strong zero is see the [FAQ](@ref faq-strong-zero)
+"""
+strong_zero(::Mode{<:Any, <:Any, <:Any, StrongZero}) where StrongZero = StrongZero
+strong_zero(::Type{<:Mode{<:Any, <:Any, <:Any, StrongZero}}) where StrongZero = StrongZero
+
 """
     struct ReverseMode{
         ReturnPrimal,

lib/EnzymeCore/src/rules.jl

@@ -5,6 +5,7 @@ import EnzymeCore: Annotation, Const, Duplicated, Mode
 export RevConfig, RevConfigWidth
 export FwdConfig, FwdConfigWidth
 export AugmentedReturn
+import ..EnzymeCore: needs_primal
 export needs_primal, needs_shadow, width, overwritten, runtime_activity
 export primal_type, shadow_type, tape_type
 

src/Enzyme.jl

@@ -54,7 +54,10 @@ import EnzymeCore:
     clear_strong_zero,
     within_autodiff,
     WithPrimal,
-    NoPrimal
+    NoPrimal,
+    needs_primal,
+    runtime_activity,
+    strong_zero
 export Annotation,
     Const,
     Active,
@@ -75,7 +78,10 @@ export Annotation,
     clear_strong_zero,
     WithPrimal,
     NoPrimal,
-    within_autodiff
+    within_autodiff,
+    needs_primal,
+    runtime_activity,
+    strong_zero
 
 import EnzymeCore: BatchDuplicatedFunc
 export BatchDuplicatedFunc