TP3/shell/tests/fixtures/t34_arith.pas

program t34;

{ t34 -- the operators no other fixture uses.

  Every one of `div', `mod', `and', `or', unary `-' and a variable `*' is
  emitted by this compiler and has never been executed by any test: t08 was
  the only fixture that multiplied and it multiplied two CONSTANTS, which
  BinOpEmit folds without emitting anything.  So `EmIDivAxCx', `EmXchgAxDx',
  `EmAndAxCx', `EmOrAxCx' and `EmNegAx' were all untested, and so is every
  instruction the Exec86 interpreter implements for them.

  The operands are deliberately VARIABLES, for the same reason: with two
  constants `p div q' folds at compile time and the runtime never runs.

  The four sign combinations of div and mod are the point.  Pascal's `div'
  truncates toward zero and `mod' takes the sign of the dividend:

       a div b = truncation of a/b toward zero
       a mod b = a - b * (a div b)

  so -17 div 5 = -3 and -17 mod 5 = -2, where a floor-division machine would
  answer -4 and 1.  ISO Modula-2, which Exec86 is written in, has Euclidean
  DIV/MOD (measured: (-7) MOD 2 = 1, 7 MOD (-2) = 1), so the interpreter has
  to convert; these eight lines are what says whether it converts the right
  way.

  `not' is absent here on purpose: it has its own fixture, t35_not, which
  is where the boolean/int split in TPSRC9 neglevel is checked. }

var
  p : integer;
  q : integer;
begin
  p := 17;
  q := 5;
  writeln (p * q);
  writeln (p + q);
  writeln (p - q);
  writeln (p div q);
  writeln (p mod q);
  writeln (-p);
  writeln ((p > q) and (q > p));
  writeln ((p > q) or (q > p));
  p := -17;
  q := 5;
  writeln (p div q);
  writeln (p mod q);
  writeln (-p);
  p := 17;
  q := -5;
  writeln (p div q);
  writeln (p mod q);
  p := -17;
  q := -5;
  writeln (p div q);
  writeln (p mod q)
end.