Implement FinalizerEscape

aviatesk · Feb 1, 2022 · 4b8b6bf · 4b8b6bf
1 parent 2f4c945
commit 4b8b6bf
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Showing 2 changed files with 44 additions and 12 deletions.
diff --git a/src/EAUtils.jl b/src/EAUtils.jl
@@ -328,6 +328,9 @@ function get_name_color(x::EscapeInfo, symbol::Bool = false)
     elseif EA.has_return_escape(x)
         name = (getname(EA.ReturnEscape), "↑")
         color = EA.has_thrown_escape(x) ? :yellow : :blue
+    elseif EA.has_finalizer_escape(x)
+        name = (getname(EA.FinalizerEscape), "&")
+        color = EA.has_thrown_escape(x) ? :yellow : :blue
     else
         name = (nothing, "*")
         color = EA.has_thrown_escape(x) ? :yellow : :bold

diff --git a/src/EscapeAnalysis.jl b/src/EscapeAnalysis.jl
@@ -9,6 +9,7 @@ export
     has_arg_escape,
     has_return_escape,
     has_thrown_escape,
+    has_finalizer_escape,
     has_all_escape
 
 const _TOP_MOD = ccall(:jl_base_relative_to, Any, (Any,), EscapeAnalysis)::Module
@@ -122,6 +123,7 @@ struct EscapeInfo
     Analyzed::Bool
     ReturnEscape::Bool
     ThrownEscape::LivenessSet
+    FinalizerEscape::Bool
     AliasInfo #::Union{IndexableFields,IndexableElements,Unindexable,Bool}
     Liveness::LivenessSet
     # TODO: ArgEscape::Int
@@ -130,6 +132,7 @@ struct EscapeInfo
         Analyzed::Bool,
         ReturnEscape::Bool,
         ThrownEscape::LivenessSet,
+        FinalizerEscape::Bool,
         AliasInfo#=::Union{IndexableFields,IndexableElements,Unindexable,Bool}=#,
         Liveness::LivenessSet,
         )
@@ -138,6 +141,7 @@ struct EscapeInfo
             Analyzed,
             ReturnEscape,
             ThrownEscape,
+            FinalizerEscape,
             AliasInfo,
             Liveness,
             )
@@ -150,13 +154,15 @@ struct EscapeInfo
         Analyzed::Bool = x.Analyzed,
         ReturnEscape::Bool = x.ReturnEscape,
         ThrownEscape::LivenessSet = x.ThrownEscape,
+        FinalizerEscape::Bool = x.FinalizerEscape,
         Liveness::LivenessSet = x.Liveness,
         )
         @nospecialize AliasInfo
         return new(
             Analyzed,
             ReturnEscape,
             ThrownEscape,
+            FinalizerEscape,
             AliasInfo,
             Liveness,
             )
@@ -177,13 +183,14 @@ const TOP_LIVENESS = LivenessSet(-1:0)
 const ARG_LIVENESS = LivenessSet(0)
 
 # the constructors
-NotAnalyzed() = EscapeInfo(false, false, BOT_THROWN_ESCAPE, false, BOT_LIVENESS) # not formally part of the lattice
-NoEscape() = EscapeInfo(true, false, BOT_THROWN_ESCAPE, false, BOT_LIVENESS)
-ArgEscape() = EscapeInfo(true, false, BOT_THROWN_ESCAPE, true, ARG_LIVENESS)
-ReturnEscape(pc::Int) = EscapeInfo(true, true, BOT_THROWN_ESCAPE, false, LivenessSet(pc))
-AllReturnEscape() = EscapeInfo(true, true, BOT_THROWN_ESCAPE, false, TOP_LIVENESS)
-ThrownEscape(pc::Int) = EscapeInfo(true, false, LivenessSet(pc), false, BOT_LIVENESS)
-AllEscape() = EscapeInfo(true, true, TOP_THROWN_ESCAPE, true, TOP_LIVENESS)
+NotAnalyzed() = EscapeInfo(false, false, BOT_THROWN_ESCAPE, false, false, BOT_LIVENESS) # not formally part of the lattice
+NoEscape() = EscapeInfo(true, false, BOT_THROWN_ESCAPE, false, false, BOT_LIVENESS)
+ArgEscape() = EscapeInfo(true, false, BOT_THROWN_ESCAPE, false, true, ARG_LIVENESS)
+ReturnEscape(pc::Int) = EscapeInfo(true, true, BOT_THROWN_ESCAPE, false, false, LivenessSet(pc))
+AllReturnEscape() = EscapeInfo(true, true, BOT_THROWN_ESCAPE, false, false, TOP_LIVENESS)
+ThrownEscape(pc::Int) = EscapeInfo(true, false, LivenessSet(pc), false, false, BOT_LIVENESS)
+FinalizerEscape(pc::Int) = EscapeInfo(true, false, BOT_THROWN_ESCAPE, true, false, LivenessSet(pc))
+AllEscape() = EscapeInfo(true, true, TOP_THROWN_ESCAPE, true, true, TOP_LIVENESS)
 
 const ⊥, ⊤ = NotAnalyzed(), AllEscape()
 
@@ -193,7 +200,9 @@ has_arg_escape(x::EscapeInfo) = 0 in x.Liveness
 has_return_escape(x::EscapeInfo) = x.ReturnEscape
 has_return_escape(x::EscapeInfo, pc::Int) = x.ReturnEscape && (-1 ∈ x.Liveness || pc in x.Liveness)
 has_thrown_escape(x::EscapeInfo) = !isempty(x.ThrownEscape)
-has_thrown_escape(x::EscapeInfo, pc::Int) = -1 ∈ x.ThrownEscape  || pc in x.ThrownEscape
+has_thrown_escape(x::EscapeInfo, pc::Int) = -1 ∈ x.ThrownEscape || pc in x.ThrownEscape
+has_finalizer_escape(x::EscapeInfo) = x.FinalizerEscape
+has_finalizer_escape(x::EscapeInfo, pc::Int) = x.FinalizerEscape && (-1 ∈ x.Liveness || pc in x.Liveness)
 has_all_escape(x::EscapeInfo) = ⊤ ⊑ₑ x
 
 # utility lattice constructors
@@ -217,6 +226,7 @@ x::EscapeInfo == y::EscapeInfo = begin
     else
         xt == yt || return false
     end
+    x.FinalizerEscape === y.FinalizerEscape || return false
     xa, ya = x.AliasInfo, y.AliasInfo
     if isa(xa, Bool)
         xa === ya || return false
@@ -267,6 +277,7 @@ x::EscapeInfo ⊑ₑ y::EscapeInfo = begin
     elseif yt !== TOP_THROWN_ESCAPE
         xt ⊆ yt || return false
     end
+    x.FinalizerEscape ≤ y.FinalizerEscape || return false
     xa, ya = x.AliasInfo, y.AliasInfo
     if isa(xa, Bool)
         xa && ya !== true && return false
@@ -442,6 +453,7 @@ x::EscapeInfo ⊔ₑ y::EscapeInfo = begin
         x.Analyzed | y.Analyzed,
         x.ReturnEscape | y.ReturnEscape,
         ThrownEscape,
+        x.FinalizerEscape | y.FinalizerEscape,
         AliasInfo,
         Liveness,
         )
@@ -559,13 +571,14 @@ struct ArgEscapeInfo
     AllEscape::Bool
     ReturnEscape::Bool
     ThrownEscape::Bool
+    FinalizerEscape::Bool
     ArgAliasing::Union{Nothing,Vector{Int}}
 end
 
 function ArgEscapeInfo(x::EscapeInfo, ArgAliasing::Union{Nothing,Vector{Int}})
     x === ⊤ && return ArgEscapeInfo(true, true, true, nothing)
     ThrownEscape = isempty(x.ThrownEscape) ? false : true
-    return ArgEscapeInfo(false, x.ReturnEscape, ThrownEscape, ArgAliasing)
+    return ArgEscapeInfo(false, x.ReturnEscape, ThrownEscape, x.FinalizerEscape, ArgAliasing)
 end
 
 # when working outside of Core.Compiler, cache as much as information for later inspection and debugging
@@ -1435,10 +1448,10 @@ function escape_foreigncall!(astate::AnalysisState, pc::Int, args::Vector{Any})
         elseif is_array_isassigned(nn)
             escape_array_isassigned!(astate, pc, args)
             return
+        elseif is_finalizer(nn)
+            escape_finalizer!(astate, pc, args)
+            return
         end
-        # if nn === :jl_gc_add_finalizer_th
-        #     # TODO add `FinalizerEscape` ?
-        # end
     end
     # NOTE array allocations might have been proven as nothrow (https://github.com/JuliaLang/julia/pull/43565)
     nothrow = is_effect_free(astate.ir, pc)
@@ -1991,6 +2004,22 @@ function array_isassigned_nothrow(args::Vector{Any}, src::IRCode)
     return true
 end
 
+is_finalizer(name::Symbol) = name === :jl_gc_add_finalizer_th
+
+function escape_finalizer!(astate::AnalysisState, pc::Int, args::Vector{Any})
+    length(args) ≥ 6 || return add_fallback_changes!(astate, pc, args)
+    println("Finalizer escape!")
+    println(pc)
+    for arg in args
+        println(arg)
+    end
+    value = args[8]
+    func = args[9]
+    # TODO: We need to analyze func
+    add_escape_change!(astate, value, FinalizerEscape(pc))
+    add_liveness_changes!(astate, pc, args, 6)
+end
+
 # # COMBAK do we want to enable this (and also backport this to Base for array allocations?)
 # import Core.Compiler: Cint, svec
 # function validate_foreigncall_args(args::Vector{Any},