line 1: logb(0,0) = fff00000,0 (-2147483648)
line 2: logb(80000000,0) = fff00000,0 (-2147483648)
line 3: logb(3ff00000,0) = 0,0 (0)
line 4: logb(bff00000,0) = 0,0 (0)
line 5: logb(80000,0) = c08ff800,0 (-1023)
line 6: logb(0,80000000) = c0904c00,0 (-1043)
line 7: logb(0,1) = c090c800,0 (-1074)
line 8: logb(80000000,1) = c090c800,0 (-1074)
line 9: logb(7ff00000,0) = 7ff00000,0 (2147483647)
line 10: logb(fff00000,0) = 7ff00000,0 (2147483647)
line 11: logb(7ff00000,ffffffff) = 7ff00000,ffffffff (2147483647)
line 12: logb(fff80000,ffffffff) = fff80000,ffffffff (-2147483648)