Update defuses based on DCE results

Compiler/src/ssair/passes.jl

@@ -1511,6 +1511,10 @@ function sroa_pass!(ir::IRCode, inlining::Union{Nothing,InliningState}=nothing)
             used_ssas[x.id] -= 1
         end
         ir = complete(compact)
+        # remove any use that has been optimized away by the DCE
+        for (intermediaries, defuse) in values(defuses)
+            filter!(x -> ir[SSAValue(x.idx)][:stmt] !== nothing, defuse.uses)
+        end
         sroa_mutables!(ir, defuses, used_ssas, lazydomtree, inlining)
         return ir
     else

Compiler/test/irpasses.jl

@@ -2030,3 +2030,19 @@ let code = Any[
     ir = Compiler.domsort_ssa!(ir, domtree)
     Compiler.verify_ir(ir)
 end
+
+# https://github.com/JuliaLang/julia/issues/57141
+# don't eliminate `setfield!` when the field is to be used
+let src = code_typed1(()) do
+        f = function ()
+            ref = Ref{Any}()
+            ref[] = 0
+            @assert isdefined(ref, :x)
+            inner() = ref[] + 1
+            (inner(), ref[])
+        end
+        first(f())
+    end
+    ex = src.code[2]
+    @test isexpr(ex, :call) && argextype(ex.args[1], src) === Const(setfield!)
+end