reserve p,p1,p2,h for Instruction-Sequence of SCM+FSA;
reserve k, l, n for Nat,
  j for Integer,
  i,i1 for Instruction of SCM+FSA;
reserve s, s1, s2 for State of SCM+FSA,
  a for read-write Int-Location,
  b for Int-Location,
  I, J for MacroInstruction of SCM+FSA,
  Ig for good MacroInstruction of SCM+FSA,
  i, j, k, m, n for Nat;

theorem
  UsedILoc if=0(b, I, J) = {b} \/ UsedILoc I \/ UsedILoc J
proof
  set I5 = Stop SCM+FSA;
  set a = b;
  set I1 = a =0_goto  (card J + 3);
  set I3 = Goto  (card I + 1);
  thus UsedILoc if=0(a, I, J) = UsedILoc (I1 ";" J ";" I3 ";" I ";" I5)
    .= (UsedILoc (I1 ";" J ";" I3 ";" I)) \/ {} by Th3,SF_MASTR:27
    .= (UsedILoc (I1 ";" J ";" I3)) \/ UsedILoc I by SF_MASTR:27
    .= (UsedILoc (I1 ";" J)) \/ UsedILoc I3 \/ UsedILoc I by SF_MASTR:27
    .= (UsedILoc (I1 ";" J)) \/ {} \/ UsedILoc I by Th5
    .= UsedIntLoc I1 \/ UsedILoc J \/ UsedILoc I by SF_MASTR:29
    .= {a} \/ UsedILoc J \/ UsedILoc I by SF_MASTR:16
    .= {a} \/ UsedILoc I \/ UsedILoc J by XBOOLE_1:4;
end;
