| st[r -- _type] .type ≤ ty0, level⊆(str, str0), is_obj(str, r, st), ∀ str, ty0, st, str0. validrefs(str, acc, ty0, st) ∧ level⊆(str, str0) → validrefs(str0, acc, ty0, st), acc = [] ∨ mkfs(class, ty, fieldvar) ' ∈ instfields(st[r -- _type] .type .class) ∧ is_referencevalue(st[r -- mkfs(class, ty, fieldvar) ']) ∧ acc .first = st[r -- mkfs(class, ty, fieldvar) '] .refval ∧ validrefs(str, acc, ty, st) ⊦ r = jvmref, validrefs(str0, r ' + acc, ty0, st) |
⊦ is_obj(str, r, st) ∧ st[r -- _type] .type ≤ ty → ( validrefs(str, r ' + refs, ty, st) ↔ refs = [] ∨ (∃ fs. fs ' ∈ instfields(st[r -- _type] .type .class) ∧ is_referencevalue(st[r -- fs ']) ∧ refs .first = st[r -- fs '] .refval ∧ validrefs(str, refs, fs .type, st)))
is_obj(str0, r, st) ∧ st[r -- _type] .type ≤ ty0, st[r -- _type] .type ≤ ty0, level⊆(str, str0), is_obj(str, r, st), ∀ str, ty0, st, str0. validrefs(str, acc, ty0, st) ∧ level⊆(str, str0) → validrefs(str0, acc, ty0, st), acc = [] ∨ mkfs(class, ty, fieldvar) ' ∈ instfields(st[r -- _type] .type .class) ∧ is_referencevalue(st[r -- mkfs(class, ty, fieldvar) ']) ∧ acc .first = st[r -- mkfs(class, ty, fieldvar) '] .refval ∧ validrefs(str, acc, ty, st) ⊦ r = jvmref, acc = [] ∨ (∃ fs. fs ' ∈ instfields(st[r -- _type] .type .class) ∧ is_referencevalue(st[r -- fs ']) ∧ acc .first = st[r -- fs '] .refval ∧ validrefs(str0, acc, fs .type, st))
[[CONCRETESIMPRULES : ([CSIMPSEQ : ⊦ is_obj(str, r, st) ∧ level⊆(str, str0) → (¬ is_obj(str0, r, st) ↔ false)])], [EXTRATERMS : (st, ty0, acc, r, str0)]]