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heap snapshot: Count the array size on the _buffer_ not on the array. #3

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@ghost ghost commented Oct 15, 2021

This way we can still count the array size plus the buffer size separately...

But it has some weirdnesses: not all the arrays are getting a buffer edge added for some remaining mysterious reason, which means this is actually worse than before, because we lose some array sizes.

So i guess we should keep it without this code unless we can fix the buffer problem. And also i'm not sure how this will work yet for arrays that contain pointers.

@NHDaly NHDaly mentioned this pull request Oct 15, 2021
29 tasks
vilterp pushed a commit that referenced this pull request Oct 19, 2021
…tional` (JuliaLang#42434)

Otherwise, in rare cases, we may see this sort of weird behavior:
```julia
julia> @eval edgecase(_) = $(Core.Compiler.InterConditional(2, Int, Any))
edgecase (generic function with 1 method)

julia> code_typed((Any,)) do x
           edgecase(x) ? x : nothing
       end
1-element Vector{Any}:
 CodeInfo(
1 ─     goto #3 if not $(QuoteNode(Core.InterConditional(2, Int64, Any)))
2 ─     return x
3 ─     return Main.nothing
) => Any

julia> code_typed((Any,)) do x
           edgecase(x) ? x : nothing
       end
1-element Vector{Any}:
 CodeInfo(
1 ─      goto #3 if not $(QuoteNode(Core.InterConditional(2, Int64, Any)))
2 ─ %2 = π (x, Int64)
└──      return %2
3 ─      return Main.nothing
) => Union{Nothing, Int64}
```
vilterp pushed a commit that referenced this pull request Dec 1, 2021
This commit complements JuliaLang#39754 and JuliaLang#39305: implements a logic to use
constant-prop'ed results for inlining at union-split callsite.
Currently it works only for cases when constant-prop' succeeded for all
(union-split) signatures.

> example
```julia
julia> mutable struct X
           # NOTE in order to confuse `fieldtype_tfunc`, we need to have at least two fields with different types
           a::Union{Nothing, Int}
           b::Symbol
       end;

julia> code_typed((X, Union{Nothing,Int})) do x, a
           # this `setproperty` call would be union-split and constant-prop will happen for
           # each signature: inlining would fail if we don't use constant-prop'ed source
           # since the approximated inlining cost of `convert(fieldtype(X, sym), a)` would
           # end up very high if we don't propagate `sym::Const(:a)`
           x.a = a
           x
       end |> only |> first
```

> before this commit
```julia
CodeInfo(
1 ─ %1 = Base.setproperty!::typeof(setproperty!)
│   %2 = (isa)(a, Nothing)::Bool
└──      goto #3 if not %2
2 ─ %4 = π (a, Nothing)
│        invoke %1(_2::X, 🅰️:Symbol, %4::Nothing)::Any
└──      goto #6
3 ─ %7 = (isa)(a, Int64)::Bool
└──      goto #5 if not %7
4 ─ %9 = π (a, Int64)
│        invoke %1(_2::X, 🅰️:Symbol, %9::Int64)::Any
└──      goto #6
5 ─      Core.throw(ErrorException("fatal error in type inference (type bound)"))::Union{}
└──      unreachable
6 ┄      return x
)
```

> after this commit
```julia
CodeInfo(
1 ─ %1 = (isa)(a, Nothing)::Bool
└──      goto #3 if not %1
2 ─      Base.setfield!(x, :a, nothing)::Nothing
└──      goto #6
3 ─ %5 = (isa)(a, Int64)::Bool
└──      goto #5 if not %5
4 ─ %7 = π (a, Int64)
│        Base.setfield!(x, :a, %7)::Int64
└──      goto #6
5 ─      Core.throw(ErrorException("fatal error in type inference (type bound)"))::Union{}
└──      unreachable
6 ┄      return x
)
```
vilterp pushed a commit that referenced this pull request Dec 1, 2021
…43226)

In order to allow `Argument`s to be printed nicely.

> before
```julia
julia> code_typed((Float64,)) do x
           sin(x)
       end
1-element Vector{Any}:
 CodeInfo(
1 ─ %1 = invoke Main.sin(_2::Float64)::Float64
└──      return %1
) => Float64

julia> code_typed((Bool,Any,Any)) do c, x, y
           z = c ? x : y
           z
       end
1-element Vector{Any}:
 CodeInfo(
1 ─      goto #3 if not c
2 ─      goto #4
3 ─      nothing::Nothing
4 ┄ %4 = φ (#2 => _3, #3 => _4)::Any
└──      return %4
) => Any
```

> after
```julia
julia> code_typed((Float64,)) do x
           sin(x)
       end
1-element Vector{Any}:
 CodeInfo(
1 ─ %1 = invoke Main.sin(x::Float64)::Float64
└──      return %1
) => Float64

julia> code_typed((Bool,Any,Any)) do c, x, y
           z = c ? x : y
           z
       end
1-element Vector{Any}:
 CodeInfo(
1 ─      goto #3 if not c
2 ─      goto #4
3 ─      nothing::Nothing
4 ┄ %4 = φ (#2 => x, #3 => y)::Any
└──      return %4
) => Any
```
vilterp pushed a commit that referenced this pull request Dec 9, 2021
…split const-prop'ed sources

This commit complements JuliaLang#39754 and JuliaLang#39305: implements a logic to use
constant-prop'ed results for inlining at union-split callsite.
Currently it works only for cases when constant-prop' succeeded for all
(union-split) signatures.

> example
```julia
julia> mutable struct X
           # NOTE in order to confuse `fieldtype_tfunc`, we need to have at least two fields with different types
           a::Union{Nothing, Int}
           b::Symbol
       end;

julia> code_typed((X, Union{Nothing,Int})) do x, a
           # this `setproperty` call would be union-split and constant-prop will happen for
           # each signature: inlining would fail if we don't use constant-prop'ed source
           # since the approximated inlining cost of `convert(fieldtype(X, sym), a)` would
           # end up very high if we don't propagate `sym::Const(:a)`
           x.a = a
           x
       end |> only |> first
```

> before this commit
```julia
CodeInfo(
1 ─ %1 = Base.setproperty!::typeof(setproperty!)
│   %2 = (isa)(a, Nothing)::Bool
└──      goto #3 if not %2
2 ─ %4 = π (a, Nothing)
│        invoke %1(_2::X, 🅰️:Symbol, %4::Nothing)::Any
└──      goto #6
3 ─ %7 = (isa)(a, Int64)::Bool
└──      goto #5 if not %7
4 ─ %9 = π (a, Int64)
│        invoke %1(_2::X, 🅰️:Symbol, %9::Int64)::Any
└──      goto #6
5 ─      Core.throw(ErrorException("fatal error in type inference (type bound)"))::Union{}
└──      unreachable
6 ┄      return x
)
```

> after this commit
```julia
CodeInfo(
1 ─ %1 = (isa)(a, Nothing)::Bool
└──      goto #3 if not %1
2 ─      Base.setfield!(x, :a, nothing)::Nothing
└──      goto #6
3 ─ %5 = (isa)(a, Int64)::Bool
└──      goto #5 if not %5
4 ─ %7 = π (a, Int64)
│        Base.setfield!(x, :a, %7)::Int64
└──      goto #6
5 ─      Core.throw(ErrorException("fatal error in type inference (type bound)"))::Union{}
└──      unreachable
6 ┄      return x
)
```
vilterp pushed a commit that referenced this pull request Dec 9, 2021
…43226)

In order to allow `Argument`s to be printed nicely.

> before
```julia
julia> code_typed((Float64,)) do x
           sin(x)
       end
1-element Vector{Any}:
 CodeInfo(
1 ─ %1 = invoke Main.sin(_2::Float64)::Float64
└──      return %1
) => Float64

julia> code_typed((Bool,Any,Any)) do c, x, y
           z = c ? x : y
           z
       end
1-element Vector{Any}:
 CodeInfo(
1 ─      goto #3 if not c
2 ─      goto #4
3 ─      nothing::Nothing
4 ┄ %4 = φ (#2 => _3, #3 => _4)::Any
└──      return %4
) => Any
```

> after
```julia
julia> code_typed((Float64,)) do x
           sin(x)
       end
1-element Vector{Any}:
 CodeInfo(
1 ─ %1 = invoke Main.sin(x::Float64)::Float64
└──      return %1
) => Float64

julia> code_typed((Bool,Any,Any)) do c, x, y
           z = c ? x : y
           z
       end
1-element Vector{Any}:
 CodeInfo(
1 ─      goto #3 if not c
2 ─      goto #4
3 ─      nothing::Nothing
4 ┄ %4 = φ (#2 => x, #3 => y)::Any
└──      return %4
) => Any
```
@NHDaly NHDaly assigned NHDaly and unassigned NHDaly Dec 20, 2021
vilterp pushed a commit that referenced this pull request Feb 3, 2022
…43226)

In order to allow `Argument`s to be printed nicely.

> before
```julia
julia> code_typed((Float64,)) do x
           sin(x)
       end
1-element Vector{Any}:
 CodeInfo(
1 ─ %1 = invoke Main.sin(_2::Float64)::Float64
└──      return %1
) => Float64

julia> code_typed((Bool,Any,Any)) do c, x, y
           z = c ? x : y
           z
       end
1-element Vector{Any}:
 CodeInfo(
1 ─      goto #3 if not c
2 ─      goto #4
3 ─      nothing::Nothing
4 ┄ %4 = φ (#2 => _3, #3 => _4)::Any
└──      return %4
) => Any
```

> after
```julia
julia> code_typed((Float64,)) do x
           sin(x)
       end
1-element Vector{Any}:
 CodeInfo(
1 ─ %1 = invoke Main.sin(x::Float64)::Float64
└──      return %1
) => Float64

julia> code_typed((Bool,Any,Any)) do c, x, y
           z = c ? x : y
           z
       end
1-element Vector{Any}:
 CodeInfo(
1 ─      goto #3 if not c
2 ─      goto #4
3 ─      nothing::Nothing
4 ┄ %4 = φ (#2 => x, #3 => y)::Any
└──      return %4
) => Any
```
@vilterp vilterp changed the title Count the array size on the _buffer_ not on the array. heap snapshot: Count the array size on the _buffer_ not on the array. Feb 10, 2022
vilterp pushed a commit that referenced this pull request Nov 17, 2022
This commit implements a simple optimization within `sroa_mutables!` to
eliminate `isdefined` call by checking load-forwardability of the field.
This optimization may be especially useful to eliminate extra allocation
of `Core.Box` involved with a capturing closure, e.g.:
```julia
julia> callit(f, args...) = f(args...);

julia> function isdefined_elim()
           local arr::Vector{Any}
           callit() do
               arr = Any[]
           end
           return arr
       end;

julia> code_typed(isdefined_elim)
```
```diff
diff --git a/_master.jl b/_pr.jl
index 3aa40ba20e5..11eccf65f32 100644
--- a/_master.jl
+++ b/_pr.jl
@@ -1,15 +1,8 @@
 1-element Vector{Any}:
  CodeInfo(
-1 ─ %1  = Core.Box::Type{Core.Box}
-│   %2  = %new(%1)::Core.Box
-│   %3  = $(Expr(:foreigncall, :(:jl_alloc_array_1d), Vector{Any}, svec(Any, Int64), 0, :(:ccall), Vector{Any}, 0, 0))::Vector{Any}
-│         Core.setfield!(%2, :contents, %3)::Vector{Any}
-│   %5  = Core.isdefined(%2, :contents)::Bool
-└──       goto #3 if not %5
-2 ─       goto #4
-3 ─       $(Expr(:throw_undef_if_not, :arr, false))::Any
-4 ┄ %9  = Core.getfield(%2, :contents)::Any
-│         Core.typeassert(%9, Vector{Any})::Vector{Any}
-│   %11 = π (%9, Vector{Any})
-└──       return %11
+1 ─ %1 = $(Expr(:foreigncall, :(:jl_alloc_array_1d), Vector{Any}, svec(Any, Int64), 0, :(:ccall), Vector{Any}, 0, 0))::Vector{Any}
+└──      goto #3 if not true
+2 ─      goto #4
+3 ─      $(Expr(:throw_undef_if_not, :arr, false))::Any
+4 ┄      return %1
 ) => Vector{Any}
```
vilterp pushed a commit that referenced this pull request Nov 17, 2022
In JuliaLang#44635, we observe that occasionally a call to
`view(::SubArray, ::Colon, ...)` dispatches to the
wrong function. The post-inlining IR is in relevant part:

```
│   │ %8   = (isa)(I, Tuple{Colon, UnitRange{Int64}, SubArray{Int64, 2, UnitRange{Int64}, Tuple{Matrix{Int64}}, false}})::Bool
└───│        goto #3 if not %8
2 ──│ %10  = π (I, Tuple{Colon, UnitRange{Int64}, SubArray{Int64, 2, UnitRange{Int64}, Tuple{Matrix{Int64}}, false}})
│   │ @ indices.jl:324 within `to_indices` @ multidimensional.jl:859
│   │┌ @ multidimensional.jl:864 within `uncolon`
│   ││┌ @ indices.jl:351 within `Slice` @ indices.jl:351
│   │││ %11  = %new(Base.Slice{Base.OneTo{Int64}}, %7)::Base.Slice{Base.OneTo{Int64}}
│   │└└
│   │┌ @ essentials.jl:251 within `tail`
│   ││ %12  = Core.getfield(%10, 2)::UnitRange{Int64}
│   ││ %13  = Core.getfield(%10, 3)::SubArray{Int64, 2, UnitRange{Int64}, Tuple{Matrix{Int64}}, false}
│   │└
│   │ @ indices.jl:324 within `to_indices`
└───│        goto #5
    │ @ indices.jl:324 within `to_indices` @ indices.jl:333
    │┌ @ tuple.jl:29 within `getindex`
3 ──││ %15  = Base.getfield(I, 1, true)::Function
│   │└
│   │        invoke Base.to_index(A::SubArray{Int64, 3, Array{Int64, 3}, Tuple{Vector{Int64}, Base.Slice{Base.OneTo{Int64}}, UnitRange{Int64}}, false}, %15::Function)::Union{}
```

Here we expect the `isa` at `%8` to always be [1]. However,
we seemingly observe the result that the branch is not taken
and we instead end up in the fallback `to_index`, which (correctly)
complains that the colon should have been dereferenced to
an index.

After some investigation of the relevant rr trace, what turns out
to happen here is that the va tuple we compute in codegen gets
garbage collected before the call to `emit_isa`, causing a use-after-free
read, which happens to make `emit_isa` think that the isa condition
is impossible, causing it to fold the branch away.

The fix is to simply add the relevant GC root. It's a bit unfortunate that this
wasn't caught by the GC verifier. It would have in principle been capable of doing
so, but it is currently disabled for C++ sources. It would be worth revisiting
this in the future to see if it can't be made to work.

Fixes JuliaLang#44635.

[1] The specialization heuristics decided to widen `Colon` to `Function`,
which doesn't make much sense here, but regardless, it shouldn't
crash.
vilterp pushed a commit that referenced this pull request Nov 17, 2022
Follows up JuliaLang#44708 -- in that PR I missed the most obvious optimization
opportunity, i.e. we can safely eliminate `isdefined` checks when all
fields are defined at allocation site.
This change allows us to eliminate capturing closure constructions when
the body and callsite of capture closure is available within a optimized
frame, e.g.:
```julia
function abmult(r::Int, x0)
    if r < 0
        r = -r
    end
    f = x -> x * r
    return @inline f(x0)
end
```
```diff
diff --git a/_master.jl b/_pr.jl
index ea06d865b75..c38f221090f 100644
--- a/_master.jl
+++ b/_pr.jl
@@ -1,24 +1,19 @@
 julia> @code_typed abmult(-3, 3)
 CodeInfo(
-1 ── %1  = Core.Box::Type{Core.Box}
-│    %2  = %new(%1, r@_2)::Core.Box
-│    %3  = Core.isdefined(%2, :contents)::Bool
-└───       goto #3 if not %3
+1 ──       goto #3 if not true
 2 ──       goto #4
 3 ──       $(Expr(:throw_undef_if_not, :r, false))::Any
-4 ┄─ %7  = (r@_2 < 0)::Any
-└───       goto #9 if not %7
-5 ── %9  = Core.isdefined(%2, :contents)::Bool
-└───       goto #7 if not %9
+4 ┄─ %4  = (r@_2 < 0)::Any
+└───       goto #9 if not %4
+5 ──       goto #7 if not true
 6 ──       goto #8
 7 ──       $(Expr(:throw_undef_if_not, :r, false))::Any
-8 ┄─ %13 = -r@_2::Any
-9 ┄─ %14 = φ (#4 => r@_2, #8 => %13)::Any
-│    %15 = Core.isdefined(%2, :contents)::Bool
-└───       goto #11 if not %15
+8 ┄─ %9  = -r@_2::Any
+9 ┄─ %10 = φ (#4 => r@_2, #8 => %9)::Any
+└───       goto #11 if not true
 10 ─       goto #12
 11 ─       $(Expr(:throw_undef_if_not, :r, false))::Any
-12 ┄ %19 = (x0 * %14)::Any
+12 ┄ %14 = (x0 * %10)::Any
 └───       goto #13
-13 ─       return %19
+13 ─       return %14
 ) => Any
```
vilterp pushed a commit that referenced this pull request Nov 17, 2022
Currently the optimizer handles abstract callsite only when there is a
single dispatch candidate (in most cases), and so inlining and static-dispatch
are prohibited when the callsite is union-split (in other word, union-split
happens only when all the dispatch candidates are concrete).

However, there are certain patterns of code (most notably our Julia-level compiler code)
that inherently need to deal with abstract callsite.
The following example is taken from `Core.Compiler` utility:
```julia
julia> @inline isType(@nospecialize t) = isa(t, DataType) && t.name === Type.body.name
isType (generic function with 1 method)

julia> code_typed((Any,)) do x # abstract, but no union-split, successful inlining
           isType(x)
       end |> only
CodeInfo(
1 ─ %1 = (x isa Main.DataType)::Bool
└──      goto #3 if not %1
2 ─ %3 = π (x, DataType)
│   %4 = Base.getfield(%3, :name)::Core.TypeName
│   %5 = Base.getfield(Type{T}, :name)::Core.TypeName
│   %6 = (%4 === %5)::Bool
└──      goto #4
3 ─      goto #4
4 ┄ %9 = φ (#2 => %6, #3 => false)::Bool
└──      return %9
) => Bool

julia> code_typed((Union{Type,Nothing},)) do x # abstract, union-split, unsuccessful inlining
           isType(x)
       end |> only
CodeInfo(
1 ─ %1 = (isa)(x, Nothing)::Bool
└──      goto #3 if not %1
2 ─      goto #4
3 ─ %4 = Main.isType(x)::Bool
└──      goto #4
4 ┄ %6 = φ (#2 => false, #3 => %4)::Bool
└──      return %6
) => Bool
```
(note that this is a limitation of the inlining algorithm, and so any
user-provided hints like callsite inlining annotation doesn't help here)

This commit enables inlining and static dispatch for abstract union-split callsite.
The core idea here is that we can simulate our dispatch semantics by
generating `isa` checks in order of the specialities of dispatch candidates:
```julia
julia> code_typed((Union{Type,Nothing},)) do x # union-split, unsuccessful inlining
                  isType(x)
              end |> only
CodeInfo(
1 ─ %1  = (isa)(x, Nothing)::Bool
└──       goto #3 if not %1
2 ─       goto #9
3 ─ %4  = (isa)(x, Type)::Bool
└──       goto #8 if not %4
4 ─ %6  = π (x, Type)
│   %7  = (%6 isa Main.DataType)::Bool
└──       goto #6 if not %7
5 ─ %9  = π (%6, DataType)
│   %10 = Base.getfield(%9, :name)::Core.TypeName
│   %11 = Base.getfield(Type{T}, :name)::Core.TypeName
│   %12 = (%10 === %11)::Bool
└──       goto #7
6 ─       goto #7
7 ┄ %15 = φ (#5 => %12, #6 => false)::Bool
└──       goto #9
8 ─       Core.throw(ErrorException("fatal error in type inference (type bound)"))::Union{}
└──       unreachable
9 ┄ %19 = φ (#2 => false, #7 => %15)::Bool
└──       return %19
) => Bool
```

Inlining/static-dispatch of abstract union-split callsite will improve
the performance in such situations (and so this commit will improve the
latency of our JIT compilation). Especially, this commit helps us avoid
excessive specializations of `Core.Compiler` code by statically-resolving
`@nospecialize`d callsites, and as the result, the # of precompiled
statements is now reduced from  `2005` ([`master`](f782430)) to `1912` (this commit).

And also, as a side effect, the implementation of our inlining algorithm
gets much simplified now since we no longer need the previous special
handlings for abstract callsites.

One possible drawback would be increased code size.
This change seems to certainly increase the size of sysimage,
but I think these numbers are in an acceptable range:
> [`master`](f782430)
```
❯ du -shk usr/lib/julia/*
17604	usr/lib/julia/corecompiler.ji
194072	usr/lib/julia/sys-o.a
169424	usr/lib/julia/sys.dylib
23784	usr/lib/julia/sys.dylib.dSYM
103772	usr/lib/julia/sys.ji
```

> this commit
```
❯ du -shk usr/lib/julia/*
17512	usr/lib/julia/corecompiler.ji
195588	usr/lib/julia/sys-o.a
170908	usr/lib/julia/sys.dylib
23776	usr/lib/julia/sys.dylib.dSYM
105360	usr/lib/julia/sys.ji
```
vilterp pushed a commit that referenced this pull request Nov 17, 2022
…Lang#45790)

Currently the `@nospecialize`-d `push!(::Vector{Any}, ...)` can only
take a single item and we will end up with runtime dispatch when we try
to call it with multiple items:
```julia
julia> code_typed(push!, (Vector{Any}, Any))
1-element Vector{Any}:
 CodeInfo(
1 ─      $(Expr(:foreigncall, :(:jl_array_grow_end), Nothing, svec(Any, UInt64), 0, :(:ccall), Core.Argument(2), 0x0000000000000001, 0x0000000000000001))::Nothing
│   %2 = Base.arraylen(a)::Int64
│        Base.arrayset(true, a, item, %2)::Vector{Any}
└──      return a
) => Vector{Any}

julia> code_typed(push!, (Vector{Any}, Any, Any))
1-element Vector{Any}:
 CodeInfo(
1 ─ %1 = Base.append!(a, iter)::Vector{Any}
└──      return %1
) => Vector{Any}
```

This commit adds a new specialization that it can take arbitrary-length
items. Our compiler should still be able to optimize the single-input 
case as before via the dispatch mechanism.
```julia
julia> code_typed(push!, (Vector{Any}, Any))
1-element Vector{Any}:
 CodeInfo(
1 ─      $(Expr(:foreigncall, :(:jl_array_grow_end), Nothing, svec(Any, UInt64), 0, :(:ccall), Core.Argument(2), 0x0000000000000001, 0x0000000000000001))::Nothing
│   %2 = Base.arraylen(a)::Int64
│        Base.arrayset(true, a, item, %2)::Vector{Any}
└──      return a
) => Vector{Any}

julia> code_typed(push!, (Vector{Any}, Any, Any))
1-element Vector{Any}:
 CodeInfo(
1 ─ %1  = Base.arraylen(a)::Int64
│         $(Expr(:foreigncall, :(:jl_array_grow_end), Nothing, svec(Any, UInt64), 0, :(:ccall), Core.Argument(2), 0x0000000000000002, 0x0000000000000002))::Nothing
└──       goto #7 if not true
2 ┄ %4  = φ (#1 => 1, #6 => %14)::Int64
│   %5  = φ (#1 => 1, #6 => %15)::Int64
│   %6  = Base.getfield(x, %4, true)::Any
│   %7  = Base.add_int(%1, %4)::Int64
│         Base.arrayset(true, a, %6, %7)::Vector{Any}
│   %9  = (%5 === 2)::Bool
└──       goto #4 if not %9
3 ─       goto #5
4 ─ %12 = Base.add_int(%5, 1)::Int64
└──       goto #5
5 ┄ %14 = φ (#4 => %12)::Int64
│   %15 = φ (#4 => %12)::Int64
│   %16 = φ (#3 => true, #4 => false)::Bool
│   %17 = Base.not_int(%16)::Bool
└──       goto #7 if not %17
6 ─       goto #2
7 ┄       return a
) => Vector{Any}
```

This commit also adds the equivalent implementations for `pushfirst!`.
vilterp pushed a commit that referenced this pull request Nov 17, 2022
When calling `jl_error()` or `jl_errorf()`, we must check to see if we
are so early in the bringup process that it is dangerous to attempt to
construct a backtrace because the data structures used to provide line
information are not properly setup.

This can be easily triggered by running:

```
julia -C invalid
```

On an `i686-linux-gnu` build, this will hit the "Invalid CPU Name"
branch in `jitlayers.cpp`, which calls `jl_errorf()`.  This in turn
calls `jl_throw()`, which will eventually call `jl_DI_for_fptr` as part
of the backtrace printing process, which fails as the object maps are
not fully initialized.  See the below `gdb` stacktrace for details:

```
$ gdb -batch -ex 'r' -ex 'bt' --args ./julia -C invalid
...
fatal: error thrown and no exception handler available.
ErrorException("Invalid CPU name "invalid".")

Thread 1 "julia" received signal SIGSEGV, Segmentation fault.
0xf75bd665 in std::_Rb_tree<unsigned int, std::pair<unsigned int const, JITDebugInfoRegistry::ObjectInfo>, std::_Select1st<std::pair<unsigned int const, JITDebugInfoRegistry::ObjectInfo> >, std::greater<unsigned int>, std::allocator<std::pair<unsigned int const, JITDebugInfoRegistry::ObjectInfo> > >::lower_bound (__k=<optimized out>, this=0x248) at /usr/local/i686-linux-gnu/include/c++/9.1.0/bits/stl_tree.h:1277
1277    /usr/local/i686-linux-gnu/include/c++/9.1.0/bits/stl_tree.h: No such file or directory.
 #0  0xf75bd665 in std::_Rb_tree<unsigned int, std::pair<unsigned int const, JITDebugInfoRegistry::ObjectInfo>, std::_Select1st<std::pair<unsigned int const, JITDebugInfoRegistry::ObjectInfo> >, std::greater<unsigned int>, std::allocator<std::pair<unsigned int const, JITDebugInfoRegistry::ObjectInfo> > >::lower_bound (__k=<optimized out>, this=0x248) at /usr/local/i686-linux-gnu/include/c++/9.1.0/bits/stl_tree.h:1277
 #1  std::map<unsigned int, JITDebugInfoRegistry::ObjectInfo, std::greater<unsigned int>, std::allocator<std::pair<unsigned int const, JITDebugInfoRegistry::ObjectInfo> > >::lower_bound (__x=<optimized out>, this=0x248) at /usr/local/i686-linux-gnu/include/c++/9.1.0/bits/stl_map.h:1258
 #2  jl_DI_for_fptr (fptr=4155049385, symsize=symsize@entry=0xffffcfa8, slide=slide@entry=0xffffcfa0, Section=Section@entry=0xffffcfb8, context=context@entry=0xffffcf94) at /cache/build/default-amdci5-4/julialang/julia-master/src/debuginfo.cpp:1181
 #3  0xf75c056a in jl_getFunctionInfo_impl (frames_out=0xffffd03c, pointer=4155049385, skipC=0, noInline=0) at /cache/build/default-amdci5-4/julialang/julia-master/src/debuginfo.cpp:1210
 #4  0xf7a6ca98 in jl_print_native_codeloc (ip=4155049385) at /cache/build/default-amdci5-4/julialang/julia-master/src/stackwalk.c:636
 #5  0xf7a6cd54 in jl_print_bt_entry_codeloc (bt_entry=0xf0798018) at /cache/build/default-amdci5-4/julialang/julia-master/src/stackwalk.c:657
 #6  jlbacktrace () at /cache/build/default-amdci5-4/julialang/julia-master/src/stackwalk.c:1090
 #7  0xf7a3cd2b in ijl_no_exc_handler (e=0xf0794010) at /cache/build/default-amdci5-4/julialang/julia-master/src/task.c:605
 #8  0xf7a3d10a in throw_internal (ct=ct@entry=0xf070c010, exception=<optimized out>, exception@entry=0xf0794010) at /cache/build/default-amdci5-4/julialang/julia-master/src/task.c:638
 #9  0xf7a3d330 in ijl_throw (e=0xf0794010) at /cache/build/default-amdci5-4/julialang/julia-master/src/task.c:654
 #10 0xf7a905aa in ijl_errorf (fmt=fmt@entry=0xf7647cd4 "Invalid CPU name \"%s\".") at /cache/build/default-amdci5-4/julialang/julia-master/src/rtutils.c:77
 #11 0xf75a4b22 in (anonymous namespace)::createTargetMachine () at /cache/build/default-amdci5-4/julialang/julia-master/src/jitlayers.cpp:823
 #12 JuliaOJIT::JuliaOJIT (this=<optimized out>) at /cache/build/default-amdci5-4/julialang/julia-master/src/jitlayers.cpp:1044
 #13 0xf7531793 in jl_init_llvm () at /cache/build/default-amdci5-4/julialang/julia-master/src/codegen.cpp:8585
 #14 0xf75318a8 in jl_init_codegen_impl () at /cache/build/default-amdci5-4/julialang/julia-master/src/codegen.cpp:8648
 #15 0xf7a51a52 in jl_restore_system_image_from_stream (f=<optimized out>) at /cache/build/default-amdci5-4/julialang/julia-master/src/staticdata.c:2131
 #16 0xf7a55c03 in ijl_restore_system_image_data (buf=0xe859c1c0 <jl_system_image_data> "8'\031\003", len=125161105) at /cache/build/default-amdci5-4/julialang/julia-master/src/staticdata.c:2184
 #17 0xf7a55cf9 in jl_load_sysimg_so () at /cache/build/default-amdci5-4/julialang/julia-master/src/staticdata.c:424
 #18 ijl_restore_system_image (fname=0x80a0900 "/build/bk_download/julia-d78fdad601/lib/julia/sys.so") at /cache/build/default-amdci5-4/julialang/julia-master/src/staticdata.c:2157
 #19 0xf7a3bdfc in _finish_julia_init (rel=rel@entry=JL_IMAGE_JULIA_HOME, ct=<optimized out>, ptls=<optimized out>) at /cache/build/default-amdci5-4/julialang/julia-master/src/init.c:741
 #20 0xf7a3c8ac in julia_init (rel=<optimized out>) at /cache/build/default-amdci5-4/julialang/julia-master/src/init.c:728
 #21 0xf7a7f61d in jl_repl_entrypoint (argc=<optimized out>, argv=0xffffddf4) at /cache/build/default-amdci5-4/julialang/julia-master/src/jlapi.c:705
 #22 0x080490a7 in main (argc=3, argv=0xffffddf4) at /cache/build/default-amdci5-4/julialang/julia-master/cli/loader_exe.c:59
```

To prevent this, we simply avoid calling `jl_errorf` this early in the
process, punting the problem to a later PR that can update guard
conditions within `jl_error*`.
vilterp pushed a commit that referenced this pull request Nov 17, 2022
…cts (JuliaLang#46712)

Currently our inference isn't able to propagate `isa`-based type
constraint for cases like `isa(Type{<:...}, DataType)` since
`typeintersect` may return `Type` object itself when taking `Type`
object and `iskindtype`-object.

This case happens in the following kind of situation (motivated by the
discussion at <JuliaLang#46553 (comment)>):
```julia
julia> function isa_kindtype(T::Type{<:AbstractVector})
           if isa(T, DataType)
               # `T` here should be inferred as `DataType` rather than `Type{<:AbstractVector}`
               return T.name.name # should be inferred as ::Symbol
           end
           return nothing
       end
isa_kindtype (generic function with 1 method)

julia> only(code_typed(isa_kindtype; optimize=false))
CodeInfo(
1 ─ %1 = (T isa Main.DataType)::Bool
└──      goto #3 if not %1
2 ─ %3 = Base.getproperty(T, :name)::Any
│   %4 = Base.getproperty(%3, :name)::Any
└──      return %4
3 ─      return Main.nothing
) => Any
```

This commit improves the situation by adding a special casing for
abstract interpretation, rather than changing the behavior of
`typeintersect`.
vilterp pushed a commit that referenced this pull request Nov 18, 2022
When calling `jl_error()` or `jl_errorf()`, we must check to see if we
are so early in the bringup process that it is dangerous to attempt to
construct a backtrace because the data structures used to provide line
information are not properly setup.

This can be easily triggered by running:

```
julia -C invalid
```

On an `i686-linux-gnu` build, this will hit the "Invalid CPU Name"
branch in `jitlayers.cpp`, which calls `jl_errorf()`.  This in turn
calls `jl_throw()`, which will eventually call `jl_DI_for_fptr` as part
of the backtrace printing process, which fails as the object maps are
not fully initialized.  See the below `gdb` stacktrace for details:

```
$ gdb -batch -ex 'r' -ex 'bt' --args ./julia -C invalid
...
fatal: error thrown and no exception handler available.
ErrorException("Invalid CPU name "invalid".")

Thread 1 "julia" received signal SIGSEGV, Segmentation fault.
0xf75bd665 in std::_Rb_tree<unsigned int, std::pair<unsigned int const, JITDebugInfoRegistry::ObjectInfo>, std::_Select1st<std::pair<unsigned int const, JITDebugInfoRegistry::ObjectInfo> >, std::greater<unsigned int>, std::allocator<std::pair<unsigned int const, JITDebugInfoRegistry::ObjectInfo> > >::lower_bound (__k=<optimized out>, this=0x248) at /usr/local/i686-linux-gnu/include/c++/9.1.0/bits/stl_tree.h:1277
1277    /usr/local/i686-linux-gnu/include/c++/9.1.0/bits/stl_tree.h: No such file or directory.
 #0  0xf75bd665 in std::_Rb_tree<unsigned int, std::pair<unsigned int const, JITDebugInfoRegistry::ObjectInfo>, std::_Select1st<std::pair<unsigned int const, JITDebugInfoRegistry::ObjectInfo> >, std::greater<unsigned int>, std::allocator<std::pair<unsigned int const, JITDebugInfoRegistry::ObjectInfo> > >::lower_bound (__k=<optimized out>, this=0x248) at /usr/local/i686-linux-gnu/include/c++/9.1.0/bits/stl_tree.h:1277
 #1  std::map<unsigned int, JITDebugInfoRegistry::ObjectInfo, std::greater<unsigned int>, std::allocator<std::pair<unsigned int const, JITDebugInfoRegistry::ObjectInfo> > >::lower_bound (__x=<optimized out>, this=0x248) at /usr/local/i686-linux-gnu/include/c++/9.1.0/bits/stl_map.h:1258
 #2  jl_DI_for_fptr (fptr=4155049385, symsize=symsize@entry=0xffffcfa8, slide=slide@entry=0xffffcfa0, Section=Section@entry=0xffffcfb8, context=context@entry=0xffffcf94) at /cache/build/default-amdci5-4/julialang/julia-master/src/debuginfo.cpp:1181
 #3  0xf75c056a in jl_getFunctionInfo_impl (frames_out=0xffffd03c, pointer=4155049385, skipC=0, noInline=0) at /cache/build/default-amdci5-4/julialang/julia-master/src/debuginfo.cpp:1210
 #4  0xf7a6ca98 in jl_print_native_codeloc (ip=4155049385) at /cache/build/default-amdci5-4/julialang/julia-master/src/stackwalk.c:636
 #5  0xf7a6cd54 in jl_print_bt_entry_codeloc (bt_entry=0xf0798018) at /cache/build/default-amdci5-4/julialang/julia-master/src/stackwalk.c:657
 #6  jlbacktrace () at /cache/build/default-amdci5-4/julialang/julia-master/src/stackwalk.c:1090
 #7  0xf7a3cd2b in ijl_no_exc_handler (e=0xf0794010) at /cache/build/default-amdci5-4/julialang/julia-master/src/task.c:605
 #8  0xf7a3d10a in throw_internal (ct=ct@entry=0xf070c010, exception=<optimized out>, exception@entry=0xf0794010) at /cache/build/default-amdci5-4/julialang/julia-master/src/task.c:638
 #9  0xf7a3d330 in ijl_throw (e=0xf0794010) at /cache/build/default-amdci5-4/julialang/julia-master/src/task.c:654
 #10 0xf7a905aa in ijl_errorf (fmt=fmt@entry=0xf7647cd4 "Invalid CPU name \"%s\".") at /cache/build/default-amdci5-4/julialang/julia-master/src/rtutils.c:77
 #11 0xf75a4b22 in (anonymous namespace)::createTargetMachine () at /cache/build/default-amdci5-4/julialang/julia-master/src/jitlayers.cpp:823
 #12 JuliaOJIT::JuliaOJIT (this=<optimized out>) at /cache/build/default-amdci5-4/julialang/julia-master/src/jitlayers.cpp:1044
 #13 0xf7531793 in jl_init_llvm () at /cache/build/default-amdci5-4/julialang/julia-master/src/codegen.cpp:8585
 #14 0xf75318a8 in jl_init_codegen_impl () at /cache/build/default-amdci5-4/julialang/julia-master/src/codegen.cpp:8648
 #15 0xf7a51a52 in jl_restore_system_image_from_stream (f=<optimized out>) at /cache/build/default-amdci5-4/julialang/julia-master/src/staticdata.c:2131
 #16 0xf7a55c03 in ijl_restore_system_image_data (buf=0xe859c1c0 <jl_system_image_data> "8'\031\003", len=125161105) at /cache/build/default-amdci5-4/julialang/julia-master/src/staticdata.c:2184
 #17 0xf7a55cf9 in jl_load_sysimg_so () at /cache/build/default-amdci5-4/julialang/julia-master/src/staticdata.c:424
 #18 ijl_restore_system_image (fname=0x80a0900 "/build/bk_download/julia-d78fdad601/lib/julia/sys.so") at /cache/build/default-amdci5-4/julialang/julia-master/src/staticdata.c:2157
 #19 0xf7a3bdfc in _finish_julia_init (rel=rel@entry=JL_IMAGE_JULIA_HOME, ct=<optimized out>, ptls=<optimized out>) at /cache/build/default-amdci5-4/julialang/julia-master/src/init.c:741
 #20 0xf7a3c8ac in julia_init (rel=<optimized out>) at /cache/build/default-amdci5-4/julialang/julia-master/src/init.c:728
 #21 0xf7a7f61d in jl_repl_entrypoint (argc=<optimized out>, argv=0xffffddf4) at /cache/build/default-amdci5-4/julialang/julia-master/src/jlapi.c:705
 #22 0x080490a7 in main (argc=3, argv=0xffffddf4) at /cache/build/default-amdci5-4/julialang/julia-master/cli/loader_exe.c:59
```

To prevent this, we simply avoid calling `jl_errorf` this early in the
process, punting the problem to a later PR that can update guard
conditions within `jl_error*`.

(cherry picked from commit 21ab24e)
vilterp pushed a commit that referenced this pull request Jan 31, 2023
Add option to `jl_print_task_backtraces(bool)` to control whether or not to print DONE tasks (JuliaLang#47933)
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3 participants