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#
# Various tests of integer arithmetic overflow
#
A = 2**62
print "A = 2**62"
unset overflow
print ""
print "unset overflow"
print "print A, A+A, -3*A"
print A, A+A, -3*A
set overflow
print ""
print "set overflow"
print "print A, A+A, -3*A"
print A, A+A, -3*A
set overflow NaN
print ""
print "set overflow NaN"
print "print A, A+A, -3*A"
print A, A+A, -3*A
print ""
print "==========================================="
print " difficult overflow detection for products "
print "==========================================="
print "set overflow"; set overflow; show overflow
B = (2**62-1) << 1
print "B = (2**62-1) << 1"
print "print B, B+1, B+2, B+3"
print B, B+1, B+2, B+3
print ""
print "B/3 = ", B/3
print "print 3074457345618258602 * 3 : ", 3074457345618258602 * 3, " Should be OK"
print "print 3074457345618258603 * 3 : ", 3074457345618258603 * 3, " Should overflow"
print ""
print "print (B-510), int(real(B-510))","\t", (B-510), int(real(B-510))
print "print (B-511), int(real(B-511))","\t", (B-511), int(real(B-511))
print ""
print "So any product > 9.22337203685477478e+18 "
print "may or may not have overflowed and needs additional tests"
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