optimizer: fix #42258, make sure to set ssaflags correctly (#42262)

Essentially, this PR adds missing `ssaflags` deletion of `type_annotate!`.
Built on top of #42260.

base/compiler/optimize.jl

@@ -85,7 +85,7 @@ mutable struct OptimizationState
         if nssavalues isa Int
             src.ssavaluetypes = Any[ Any for i = 1:nssavalues ]
         else
-            nssavalues = length(src.ssavaluetypes)
+            nssavalues = length(src.ssavaluetypes::Vector{Any})
         end
         nslots = length(src.slotflags)
         slottypes = src.slottypes

base/compiler/ssair/legacy.jl

@@ -29,9 +29,10 @@ function inflate_ir(ci::CodeInfo, sptypes::Vector{Any}, argtypes::Vector{Any})
             code[i] = stmt
         end
     end
-    ssavaluetypes = ci.ssavaluetypes
     nstmts = length(code)
-    ssavaluetypes = ci.ssavaluetypes isa Vector{Any} ? copy(ci.ssavaluetypes) : Any[ Any for i = 1:(ci.ssavaluetypes::Int) ]
+    ssavaluetypes = let ssavaluetypes = ci.ssavaluetypes
+        ssavaluetypes isa Vector{Any} ? copy(ssavaluetypes) : Any[ Any for i = 1:(ssavaluetypes::Int) ]
+    end
     stmts = InstructionStream(code, ssavaluetypes, Any[nothing for i = 1:nstmts], copy(ci.codelocs), copy(ci.ssaflags))
     ir = IRCode(stmts, cfg, collect(LineInfoNode, ci.linetable), argtypes, Any[], sptypes)
     return ir

base/compiler/ssair/slot2ssa.jl

@@ -177,13 +177,14 @@ function strip_trailing_junk!(ci::CodeInfo, code::Vector{Any}, info::Vector{Any}
     # Remove `nothing`s at the end, we don't handle them well
     # (we expect the last instruction to be a terminator)
     ssavaluetypes = ci.ssavaluetypes::Vector{Any}
+    (; codelocs, ssaflags) = ci
     for i = length(code):-1:1
         if code[i] !== nothing
             resize!(code, i)
             resize!(ssavaluetypes, i)
-            resize!(ci.codelocs, i)
+            resize!(codelocs, i)
             resize!(info, i)
-            resize!(ci.ssaflags, i)
+            resize!(ssaflags, i)
             break
         end
     end
@@ -193,9 +194,9 @@ function strip_trailing_junk!(ci::CodeInfo, code::Vector{Any}, info::Vector{Any}
     if !isa(term, GotoIfNot) && !isa(term, GotoNode) && !isa(term, ReturnNode)
         push!(code, ReturnNode())
         push!(ssavaluetypes, Union{})
-        push!(ci.codelocs, 0)
+        push!(codelocs, 0)
         push!(info, nothing)
-        push!(ci.ssaflags, IR_FLAG_NULL)
+        push!(ssaflags, IR_FLAG_NULL)
     end
     nothing
 end

base/compiler/typeinfer.jl

@@ -475,6 +475,7 @@ function finish(me::InferenceState, interp::AbstractInterpreter)
     end
     me.result.valid_worlds = me.valid_worlds
     me.result.result = me.bestguess
+    validate_code_in_debug_mode(me.linfo, me.src, "inferred")
     nothing
 end
 
@@ -666,6 +667,7 @@ function type_annotate!(sv::InferenceState, run_optimizer::Bool)
                 deleteat!(ssavaluetypes, i)
                 deleteat!(src.codelocs, i)
                 deleteat!(sv.stmt_info, i)
+                deleteat!(src.ssaflags, i)
                 nexpr -= 1
                 changemap[oldidx] = -1
                 continue

base/compiler/validation.jl

@@ -48,6 +48,7 @@ const EMPTY_SLOTNAMES = "slotnames field is empty"
 const SLOTFLAGS_MISMATCH = "length(slotnames) < length(slotflags)"
 const SSAVALUETYPES_MISMATCH = "not all SSAValues in AST have a type in ssavaluetypes"
 const SSAVALUETYPES_MISMATCH_UNINFERRED = "uninferred CodeInfo ssavaluetypes field does not equal the number of present SSAValues"
+const SSAFLAGS_MISMATCH = "not all SSAValues have a corresponding `ssaflags`"
 const NON_TOP_LEVEL_METHOD = "encountered `Expr` head `:method` in non-top-level code (i.e. `nargs` > 0)"
 const NON_TOP_LEVEL_GLOBAL = "encountered `Expr` head `:global` in non-top-level code (i.e. `nargs` > 0)"
 const SIGNATURE_NARGS_MISMATCH = "method signature does not match number of method arguments"
@@ -183,13 +184,16 @@ function validate_code!(errors::Vector{>:InvalidCodeError}, c::CodeInfo, is_top_
     nssavals = length(c.code)
     !is_top_level && nslotnames == 0 && push!(errors, InvalidCodeError(EMPTY_SLOTNAMES))
     nslotnames < nslotflags && push!(errors, InvalidCodeError(SLOTFLAGS_MISMATCH, (nslotnames, nslotflags)))
-    if c.inferred
-        nssavaluetypes = length(c.ssavaluetypes::Vector{Any})
+    ssavaluetypes = c.ssavaluetypes
+    if isa(ssavaluetypes, Vector{Any})
+        nssavaluetypes = length(ssavaluetypes)
         nssavaluetypes < nssavals && push!(errors, InvalidCodeError(SSAVALUETYPES_MISMATCH, (nssavals, nssavaluetypes)))
     else
-        ssavaluetypes = c.ssavaluetypes::Int
-        ssavaluetypes != nssavals && push!(errors, InvalidCodeError(SSAVALUETYPES_MISMATCH_UNINFERRED, (nssavals, ssavaluetypes)))
+        nssavaluetypes = ssavaluetypes::Int
+        nssavaluetypes ≠ nssavals && push!(errors, InvalidCodeError(SSAVALUETYPES_MISMATCH_UNINFERRED, (nssavals, nssavaluetypes)))
     end
+    nssaflags = length(c.ssaflags)
+    nssavals ≠ nssaflags && push!(errors, InvalidCodeError(SSAFLAGS_MISMATCH, (nssavals, nssaflags)))
     return errors
 end
 

test/compiler/ssair.jl

@@ -314,3 +314,23 @@ end
 # Issue #41975 - SSA conversion drops type check
 f_if_typecheck() = (if nothing; end; unsafe_load(Ptr{Int}(0)))
 @test_throws TypeError f_if_typecheck()
+
+@test let # https://github.com/JuliaLang/julia/issues/42258
+    code = quote
+        function foo()
+            a = @noinline rand(rand(0:10))
+            if isempty(a)
+                err = BoundsError(a)
+                throw(err)
+                return nothing
+            end
+            return a
+        end
+        code_typed(foo; optimize=true)
+
+        code_typed(Core.Compiler.setindex!, (Core.Compiler.UseRef,Core.Compiler.NewSSAValue); optimize=true)
+    end |> string
+    cmd = `$(Base.julia_cmd()) -g 2 -e $code`
+    stderr = IOBuffer()
+    success(pipeline(Cmd(cmd); stdout=stdout, stderr=stderr)) && isempty(String(take!(stderr)))
+end

test/compiler/validation.jl

@@ -105,6 +105,14 @@ end
     @test errors[1].kind === Core.Compiler.SSAVALUETYPES_MISMATCH_UNINFERRED
 end
 
+@testset "SSAFLAGS_MISMATCH" begin
+    c = copy(c0)
+    empty!(c.ssaflags)
+    errors = Core.Compiler.validate_code(c)
+    @test length(errors) == 1
+    @test errors[1].kind === Core.Compiler.SSAFLAGS_MISMATCH
+end
+
 @testset "SIGNATURE_NARGS_MISMATCH" begin
     old_sig = mi.def.sig
     mi.def.sig = Tuple{1,2}