minor fix on getfield_nothrow (#52083)

- fixed index of `order` when there are 5 arguments
- add type check for `boundscheck` argument

Author: aviatesk

base/compiler/tfuncs.jl

@@ -929,29 +929,31 @@ function getfield_boundscheck((; fargs, argtypes)::ArgInfo) # Symbol
     elseif length(argtypes) == 4
         fargs !== nothing && (farg = fargs[4])
         boundscheck = argtypes[4]
-        isvarargtype(boundscheck) && return :unknown
+        isvarargtype(boundscheck) && return :unsafe
         if widenconst(boundscheck) === Symbol
             return :on
         end
     elseif length(argtypes) == 5
         fargs !== nothing && (farg = fargs[5])
         boundscheck = argtypes[5]
     else
-        return :unknown
+        return :unsafe
     end
-    isvarargtype(boundscheck) && return :unknown
+    isvarargtype(boundscheck) && return :unsafe
     boundscheck = widenconditional(boundscheck)
     if widenconst(boundscheck) === Bool
         if isa(boundscheck, Const)
             return boundscheck.val::Bool ? :on : :off
         elseif farg !== nothing && isexpr(farg, :boundscheck)
             return :boundscheck
         end
+        return :unknown
     end
-    return :unknown
+    return :unsafe
 end
 
 function getfield_nothrow(𝕃::AbstractLattice, arginfo::ArgInfo, boundscheck::Symbol=getfield_boundscheck(arginfo))
+    boundscheck === :unsafe && return false
     (;argtypes) = arginfo
     ordering = Const(:not_atomic)
     if length(argtypes) == 4
@@ -960,7 +962,7 @@ function getfield_nothrow(𝕃::AbstractLattice, arginfo::ArgInfo, boundscheck::
             ordering = argtypes[4]
         end
     elseif length(argtypes) == 5
-        ordering = argtypes[5]
+        ordering = argtypes[4]
     elseif length(argtypes) != 3
         return false
     end

test/compiler/effects.jl

@@ -497,6 +497,25 @@ end |> Core.Compiler.is_nothrow
     getfield(t, i, false) # invalid name type
 end |> !Core.Compiler.is_nothrow
 
+@test Base.infer_effects((Some{Any},)) do some
+    getfield(some, 1, :not_atomic)
+end |> Core.Compiler.is_nothrow
+@test Base.infer_effects((Some{Any},)) do some
+    getfield(some, 1, :invalid_atomic_spec)
+end |> !Core.Compiler.is_nothrow
+@test Base.infer_effects((Some{Any},Bool)) do some, boundscheck
+    getfield(some, 1, boundscheck)
+end |> Core.Compiler.is_nothrow
+@test Base.infer_effects((Some{Any},Bool)) do some, boundscheck
+    getfield(some, 1, :not_atomic, boundscheck)
+end |> Core.Compiler.is_nothrow
+@test Base.infer_effects((Some{Any},Bool)) do some, boundscheck
+    getfield(some, 1, :invalid_atomic_spec, boundscheck)
+end |> !Core.Compiler.is_nothrow
+@test Base.infer_effects((Some{Any},Any)) do some, boundscheck
+    getfield(some, 1, :not_atomic, boundscheck)
+end |> !Core.Compiler.is_nothrow
+
 @test Core.Compiler.is_consistent(Base.infer_effects(setindex!, (Base.RefValue{Int}, Int)))
 
 # :inaccessiblememonly effect