Merge pull request #21 from N5N3/N5N3-patch-3-1

N5 n3 patch 3 1

NEWS.md

@@ -58,6 +58,7 @@ Standard library changes
   constructing the range. ([#40382])
 * TCP socket objects now expose `closewrite` functionality and support half-open mode usage ([#40783]).
 * Intersect returns a result with the eltype of the type-promoted eltypes of the two inputs ([#41769]).
+* `Iterators.countfrom` now accepts any type that defines `+`. ([#37747])
 
 #### InteractiveUtils
 * A new macro `@time_imports` for reporting any time spent importing packages and their dependencies ([#41612])

base/broadcast.jl

@@ -1087,10 +1087,12 @@ broadcasted(::DefaultArrayStyle{1}, ::typeof(-), r::LinRange) = LinRange(-r.star
 # For #18336 we need to prevent promotion of the step type:
 broadcasted(::DefaultArrayStyle{1}, ::typeof(+), r::AbstractRange, x::Number) = range(first(r) + x, step=step(r), length=length(r))
 broadcasted(::DefaultArrayStyle{1}, ::typeof(+), x::Number, r::AbstractRange) = range(x + first(r), step=step(r), length=length(r))
-broadcasted(::DefaultArrayStyle{1}, ::typeof(+), r::OrdinalRange, x::Real) = range(first(r) + x, last(r) + x, step=step(r))
-broadcasted(::DefaultArrayStyle{1}, ::typeof(+), x::Real, r::Real) = range(x + first(r), x + last(r), step=step(r))
-broadcasted(::DefaultArrayStyle{1}, ::typeof(+), r::AbstractUnitRange, x::Real) = range(first(r) + x, last(r) + x)
-broadcasted(::DefaultArrayStyle{1}, ::typeof(+), x::Real, r::AbstractUnitRange) = range(x + first(r), x + last(r))
+broadcasted(::DefaultArrayStyle{1}, ::typeof(+), r::OrdinalRange, x::Integer) = range(first(r) + x, last(r) + x, step=step(r))
+broadcasted(::DefaultArrayStyle{1}, ::typeof(+), x::Integer, r::OrdinalRange) = range(x + first(r), x + last(r), step=step(r))
+broadcasted(::DefaultArrayStyle{1}, ::typeof(+), r::AbstractUnitRange, x::Integer) = range(first(r) + x, last(r) + x)
+broadcasted(::DefaultArrayStyle{1}, ::typeof(+), x::Integer, r::AbstractUnitRange) = range(x + first(r), x + last(r))
+broadcasted(::DefaultArrayStyle{1}, ::typeof(+), r::AbstractUnitRange, x::Real) = range(first(r) + x, length=length(r))
+broadcasted(::DefaultArrayStyle{1}, ::typeof(+), x::Real, r::AbstractUnitRange) = range(x + first(r), length=length(r))
 broadcasted(::DefaultArrayStyle{1}, ::typeof(+), r::StepRangeLen{T}, x::Number) where T =
     StepRangeLen{typeof(T(r.ref)+x)}(r.ref + x, r.step, length(r), r.offset)
 broadcasted(::DefaultArrayStyle{1}, ::typeof(+), x::Number, r::StepRangeLen{T}) where T =
@@ -1101,9 +1103,10 @@ broadcasted(::DefaultArrayStyle{1}, ::typeof(+), r1::AbstractRange, r2::Abstract
 
 broadcasted(::DefaultArrayStyle{1}, ::typeof(-), r::AbstractRange, x::Number) = range(first(r) - x, step=step(r), length=length(r))
 broadcasted(::DefaultArrayStyle{1}, ::typeof(-), x::Number, r::AbstractRange) = range(x - first(r), step=-step(r), length=length(r))
-broadcasted(::DefaultArrayStyle{1}, ::typeof(-), r::OrdinalRange, x::Real) = range(first(r) - x, last(r) - x, step=step(r))
-broadcasted(::DefaultArrayStyle{1}, ::typeof(-), x::Real, r::OrdinalRange) = range(x - first(r), x - last(r), step=-step(r))
-broadcasted(::DefaultArrayStyle{1}, ::typeof(-), r::AbstractUnitRange, x::Real) = range(first(r) - x, last(r) - x)
+broadcasted(::DefaultArrayStyle{1}, ::typeof(-), r::OrdinalRange, x::Integer) = range(first(r) - x, last(r) - x, step=step(r))
+broadcasted(::DefaultArrayStyle{1}, ::typeof(-), x::Integer, r::OrdinalRange) = range(x - first(r), x - last(r), step=-step(r))
+broadcasted(::DefaultArrayStyle{1}, ::typeof(-), r::AbstractUnitRange, x::Integer) = range(first(r) - x, last(r) - x)
+broadcasted(::DefaultArrayStyle{1}, ::typeof(-), r::AbstractUnitRange, x::Real) = range(first(r) - x, length=length(r))
 broadcasted(::DefaultArrayStyle{1}, ::typeof(-), r::StepRangeLen{T}, x::Number) where T =
     StepRangeLen{typeof(T(r.ref)-x)}(r.ref - x, r.step, length(r), r.offset)
 broadcasted(::DefaultArrayStyle{1}, ::typeof(-), x::Number, r::StepRangeLen{T}) where T =

base/compiler/ssair/ir.jl

@@ -1316,7 +1316,7 @@ function iterate(compact::IncrementalCompact, (idx, active_bb)::Tuple{Int, Int}=
         compact.result[old_result_idx][:inst]), (compact.idx, active_bb)
 end
 
-function maybe_erase_unused!(extra_worklist, compact, idx, callback = x->nothing)
+function maybe_erase_unused!(extra_worklist::Vector{Int}, compact::IncrementalCompact, idx::Int, callback = x::SSAValue->nothing)
     stmt = compact.result[idx][:inst]
     stmt === nothing && return false
     if compact_exprtype(compact, SSAValue(idx)) === Bottom

base/compiler/ssair/passes.jl

@@ -110,7 +110,8 @@ function compute_value_for_use(ir::IRCode, domtree::DomTree, allblocks::Vector{I
     end
 end
 
-function simple_walk(compact::IncrementalCompact, @nospecialize(defssa#=::AnySSAValue=#), pi_callback=(pi, idx)->false)
+function simple_walk(compact::IncrementalCompact, @nospecialize(defssa#=::AnySSAValue=#),
+                     callback = (@nospecialize(pi), @nospecialize(idx)) -> false)
     while true
         if isa(defssa, OldSSAValue)
             if already_inserted(compact, defssa)
@@ -124,7 +125,7 @@ function simple_walk(compact::IncrementalCompact, @nospecialize(defssa#=::AnySSA
         end
         def = compact[defssa]
         if isa(def, PiNode)
-            if pi_callback(def, defssa)
+            if callback(def, defssa)
                 return defssa
             end
             def = def.val
@@ -135,7 +136,7 @@ function simple_walk(compact::IncrementalCompact, @nospecialize(defssa#=::AnySSA
             end
             defssa = def
         elseif isa(def, AnySSAValue)
-            pi_callback(def, defssa)
+            callback(def, defssa)
             if isa(def, SSAValue)
                 is_old(compact, defssa) && (def = OldSSAValue(def.id))
             end
@@ -148,12 +149,15 @@ function simple_walk(compact::IncrementalCompact, @nospecialize(defssa#=::AnySSA
     end
 end
 
-function simple_walk_constraint(compact::IncrementalCompact, @nospecialize(defidx), @nospecialize(typeconstraint) = types(compact)[defidx])
+function simple_walk_constraint(compact::IncrementalCompact, @nospecialize(defssa#=::AnySSAValue=#),
+                                @nospecialize(typeconstraint) = types(compact)[defssa])
     callback = function (@nospecialize(pi), @nospecialize(idx))
-        isa(pi, PiNode) && (typeconstraint = typeintersect(typeconstraint, widenconst(pi.typ)))
+        if isa(pi, PiNode)
+            typeconstraint = typeintersect(typeconstraint, widenconst(pi.typ))
+        end
         return false
     end
-    def = simple_walk(compact, defidx, callback)
+    def = simple_walk(compact, defssa, callback)
     return Pair{Any, Any}(def, typeconstraint)
 end
 
@@ -273,8 +277,10 @@ function is_getfield_captures(@nospecialize(def), compact::IncrementalCompact)
     return oc ⊑ Core.OpaqueClosure
 end
 
-function lift_leaves(compact::IncrementalCompact, @nospecialize(stmt),
-        @nospecialize(result_t), field::Int, leaves::Vector{Any})
+# try to compute lifted values that can replace `getfield(x, field)` call
+# where `x` is an immutable struct that are defined at any of `leaves`
+function lift_leaves(compact::IncrementalCompact,
+                     @nospecialize(result_t), field::Int, leaves::Vector{Any})
     # For every leaf, the lifted value
     lifted_leaves = IdDict{Any, Any}()
     maybe_undef = false
@@ -396,13 +402,13 @@ function lift_leaves(compact::IncrementalCompact, @nospecialize(stmt),
         elseif isa(leaf, Union{Argument, Expr})
             return nothing
         end
-        !ismutable(leaf) || return nothing
+        ismutable(leaf) && return nothing
         isdefined(leaf, field) || return nothing
         val = getfield(leaf, field)
         is_inlineable_constant(val) || return nothing
         lifted_leaves[leaf_key] = RefValue{Any}(quoted(val))
     end
-    lifted_leaves, maybe_undef
+    return lifted_leaves, maybe_undef
 end
 
 make_MaybeUndef(@nospecialize(typ)) = isa(typ, MaybeUndef) ? typ : MaybeUndef(typ)
@@ -415,13 +421,11 @@ function lift_comparison!(compact::IncrementalCompact, idx::Int,
         typeconstraint = widenconst(c2)
         val = stmt.args[3]
     else
-        cmp = c2
+        cmp = c2::Const
         typeconstraint = widenconst(c1)
         val = stmt.args[2]
     end
 
-    is_type_only = isdefined(typeof(cmp), :instance)
-
     if isa(val, Union{OldSSAValue, SSAValue})
         val, typeconstraint = simple_walk_constraint(compact, val, typeconstraint)
     end
@@ -497,7 +501,7 @@ function perform_lifting!(compact::IncrementalCompact,
             if is_old(compact, old_node_ssa) && isa(val, SSAValue)
                 val = OldSSAValue(val.id)
             end
-            if isa(val, Union{NewSSAValue, SSAValue, OldSSAValue})
+            if isa(val, AnySSAValue)
                 val = simple_walk(compact, val)
             end
             if val in keys(lifted_leaves)
@@ -508,11 +512,12 @@ function perform_lifting!(compact::IncrementalCompact,
                     continue
                 end
                 lifted_val = lifted_val.x
-                if isa(lifted_val, Union{NewSSAValue, SSAValue, OldSSAValue})
-                    lifted_val = simple_walk(compact, lifted_val, (pi, idx)->true)
+                if isa(lifted_val, AnySSAValue)
+                    callback = (@nospecialize(pi), @nospecialize(idx)) -> true
+                    lifted_val = simple_walk(compact, lifted_val, callback)
                 end
                 push!(new_node.values, lifted_val)
-            elseif isa(val, Union{NewSSAValue, SSAValue, OldSSAValue}) && val in keys(reverse_mapping)
+            elseif isa(val, AnySSAValue) && val in keys(reverse_mapping)
                 push!(new_node.edges, edge)
                 push!(new_node.values, lifted_phis[reverse_mapping[val]].ssa)
             else
@@ -532,14 +537,31 @@ function perform_lifting!(compact::IncrementalCompact,
 
     if stmt_val in keys(lifted_leaves)
         stmt_val = lifted_leaves[stmt_val]
-    elseif isa(stmt_val, Union{NewSSAValue, SSAValue, OldSSAValue}) && stmt_val in keys(reverse_mapping)
+    elseif isa(stmt_val, AnySSAValue) && stmt_val in keys(reverse_mapping)
         stmt_val = RefValue{Any}(lifted_phis[reverse_mapping[stmt_val]].ssa)
     end
 
     return stmt_val
 end
 
-assertion_counter = 0
+"""
+    getfield_elim_pass!(ir::IRCode) -> newir::IRCode
+
+`getfield` elimination pass, a.k.a. Scalar Replacements of Aggregates optimization.
+
+This pass is based on a local alias analysis that collects field information by def-use chain walking.
+It looks for struct allocation sites ("definitions"), and `getfield` calls as well as
+`:foreigncall`s that preserve the structs ("usages"). If "definitions" have enough information,
+then this pass will replace corresponding usages with lifted values.
+`mutable struct`s require additional cares and need to be handled separately from immutables.
+For `mutable struct`s, `setfield!` calls account for "definitions" also, and the pass should
+give up the lifting conservatively when there are any "intermediate usages" that may escape
+the mutable struct (e.g. non-inlined generic function call that takes the mutable struct as
+its argument).
+
+In a case when all usages are fully eliminated, `struct` allocation may also be erased as
+a result of dead code elimination.
+"""
 function getfield_elim_pass!(ir::IRCode)
     compact = IncrementalCompact(ir)
     insertions = Vector{Any}()
@@ -554,7 +576,6 @@ function getfield_elim_pass!(ir::IRCode)
         result_t = compact_exprtype(compact, SSAValue(idx))
         is_getfield = is_setfield = false
         field_ordering = :unspecified
-        is_ccall = false
         # Step 1: Check whether the statement we're looking at is a getfield/setfield!
         if is_known_call(stmt, setfield!, compact)
             is_setfield = true
@@ -610,8 +631,8 @@ function getfield_elim_pass!(ir::IRCode)
             old_preserves = stmt.args[(6+nccallargs):end]
             for (pidx, preserved_arg) in enumerate(old_preserves)
                 isa(preserved_arg, SSAValue) || continue
-                let intermediaries = IdSet()
-                    callback = function(@nospecialize(pi), ssa::AnySSAValue)
+                let intermediaries = IdSet{Int}()
+                    callback = function (@nospecialize(pi), @nospecialize(ssa))
                         push!(intermediaries, ssa.id)
                         return false
                     end
@@ -670,8 +691,8 @@ function getfield_elim_pass!(ir::IRCode)
 
         if ismutabletype(struct_typ)
             isa(def, SSAValue) || continue
-            let intermediaries = IdSet()
-                callback = function(@nospecialize(pi), ssa::AnySSAValue)
+            let intermediaries = IdSet{Int}()
+                callback = function (@nospecialize(pi), @nospecialize(ssa))
                     push!(intermediaries, ssa.id)
                     return false
                 end
@@ -691,6 +712,8 @@ function getfield_elim_pass!(ir::IRCode)
             continue
         end
 
+        # perform SROA on immutable structs here on
+
         if isa(def, Union{OldSSAValue, SSAValue})
             def, typeconstraint = simple_walk_constraint(compact, def, typeconstraint)
         end
@@ -703,7 +726,7 @@ function getfield_elim_pass!(ir::IRCode)
         field = try_compute_fieldidx(struct_typ, field)
         field === nothing && continue
 
-        r = lift_leaves(compact, stmt, result_t, field, leaves)
+        r = lift_leaves(compact, result_t, field, leaves)
         r === nothing && continue
         lifted_leaves, any_undef = r
 
@@ -736,14 +759,13 @@ function getfield_elim_pass!(ir::IRCode)
             @assert val !== nothing
         end
 
-        global assertion_counter
-        assertion_counter::Int += 1
+        # global assertion_counter
+        # assertion_counter::Int += 1
         #insert_node_here!(compact, Expr(:assert_egal, Symbol(string("assert_egal_", assertion_counter)), SSAValue(idx), val), nothing, 0, true)
         #continue
         compact[idx] = val === nothing ? nothing : val.x
     end
 
-
     non_dce_finish!(compact)
     # Copy the use count, `simple_dce!` may modify it and for our predicate
     # below we need it consistent with the state of the IR here (after tracking
@@ -874,11 +896,12 @@ function getfield_elim_pass!(ir::IRCode)
     end
     ir
 end
+# assertion_counter = 0
 
 function adce_erase!(phi_uses::Vector{Int}, extra_worklist::Vector{Int}, compact::IncrementalCompact, idx::Int)
     # return whether this made a change
     if isa(compact.result[idx][:inst], PhiNode)
-        return maybe_erase_unused!(extra_worklist, compact, idx, val -> phi_uses[val.id] -= 1)
+        return maybe_erase_unused!(extra_worklist, compact, idx, val::SSAValue -> phi_uses[val.id] -= 1)
     else
         return maybe_erase_unused!(extra_worklist, compact, idx)
     end
@@ -893,7 +916,7 @@ function count_uses(@nospecialize(stmt), uses::Vector{Int})
     end
 end
 
-function mark_phi_cycles(compact::IncrementalCompact, safe_phis::BitSet, phi::Int)
+function mark_phi_cycles!(compact::IncrementalCompact, safe_phis::BitSet, phi::Int)
     worklist = Int[]
     push!(worklist, phi)
     while !isempty(worklist)
@@ -909,6 +932,11 @@ function mark_phi_cycles(compact::IncrementalCompact, safe_phis::BitSet, phi::In
     end
 end
 
+"""
+    adce_pass!(ir::IRCode) -> newir::IRCode
+
+Aggressive Dead Code Elimination pass to eliminate code.
+"""
 function adce_pass!(ir::IRCode)
     phi_uses = fill(0, length(ir.stmts) + length(ir.new_nodes))
     all_phis = Int[]
@@ -940,7 +968,7 @@ function adce_pass!(ir::IRCode)
         for phi in all_phis
             # Save any phi cycles that have non-phi uses
             if compact.used_ssas[phi] - phi_uses[phi] != 0
-                mark_phi_cycles(compact, safe_phis, phi)
+                mark_phi_cycles!(compact, safe_phis, phi)
             end
         end
         for phi in all_phis

base/compiler/ssair/verify.jl

@@ -202,6 +202,10 @@ function verify_ir(ir::IRCode, print::Bool=true)
                         @verify_error "SSAValue as assignment LHS"
                         error("")
                     end
+                    if stmt.args[2] isa GlobalRef
+                        # undefined GlobalRef as assignment RHS is OK
+                        continue
+                    end
                 elseif stmt.head === :gc_preserve_end
                     # We allow gc_preserve_end tokens to span across try/catch
                     # blocks, which isn't allowed for regular SSA values, so

base/compiler/typelimits.jl

@@ -377,26 +377,25 @@ function tmerge(@nospecialize(typea), @nospecialize(typeb))
         return Bool
     end
     # type-lattice for Const and PartialStruct wrappers
-    if (isa(typea, PartialStruct) || isa(typea, Const)) &&
-       (isa(typeb, PartialStruct) || isa(typeb, Const)) &&
-        widenconst(typea) === widenconst(typeb)
+    if ((isa(typea, PartialStruct) || isa(typea, Const)) &&
+        (isa(typeb, PartialStruct) || isa(typeb, Const)) &&
+        widenconst(typea) === widenconst(typeb))
 
-       typea_nfields = nfields_tfunc(typea)
-       typeb_nfields = nfields_tfunc(typeb)
-       if !isa(typea_nfields, Const) || !isa(typeb_nfields, Const) || typea_nfields.val !== typeb_nfields.val
+        typea_nfields = nfields_tfunc(typea)
+        typeb_nfields = nfields_tfunc(typeb)
+        if !isa(typea_nfields, Const) || !isa(typeb_nfields, Const) || typea_nfields.val !== typeb_nfields.val
             return widenconst(typea)
-       end
+        end
 
-       type_nfields = typea_nfields.val::Int
-       fields = Vector{Any}(undef, type_nfields)
-       anyconst = false
-       for i = 1:type_nfields
+        type_nfields = typea_nfields.val::Int
+        fields = Vector{Any}(undef, type_nfields)
+        anyconst = false
+        for i = 1:type_nfields
             fields[i] = tmerge(getfield_tfunc(typea, Const(i)),
                                getfield_tfunc(typeb, Const(i)))
             anyconst |= has_nontrivial_const_info(fields[i])
-       end
-       return anyconst ? PartialStruct(widenconst(typea), fields) :
-            widenconst(typea)
+        end
+        return anyconst ? PartialStruct(widenconst(typea), fields) : widenconst(typea)
     end
     if isa(typea, PartialOpaque) && isa(typeb, PartialOpaque) && widenconst(typea) == widenconst(typeb)
         if !(typea.source === typeb.source &&

base/iterators.jl

@@ -592,8 +592,8 @@ IteratorSize(::Type{<:Rest{I}}) where {I} = rest_iteratorsize(IteratorSize(I))
 
 # Count -- infinite counting
 
-struct Count{S<:Number}
-    start::S
+struct Count{T,S}
+    start::T
     step::S
 end
 
@@ -613,11 +613,13 @@ julia> for v in Iterators.countfrom(5, 2)
 9
 ```
 """
-countfrom(start::Number, step::Number) = Count(promote(start, step)...)
-countfrom(start::Number)               = Count(start, oneunit(start))
-countfrom()                            = Count(1, 1)
+countfrom(start::T, step::S) where {T,S} = Count{typeof(start+step),S}(start, step)
+countfrom(start::Number, step::Number)   = Count(promote(start, step)...)
+countfrom(start)                         = Count(start, oneunit(start))
+countfrom()                              = Count(1, 1)
 
-eltype(::Type{Count{S}}) where {S} = S
+
+eltype(::Type{Count{T,S}}) where {T,S} = T
 
 iterate(it::Count, state=it.start) = (state, state + it.step)