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Floating Point Support

Currently working

  • Basic Arithmetic
    • Add, Subtract, Multiply, Divide
  • Compare
    • ==, !=, <, ⇐, >, >= for ordered and unodered
  • Conversion between single and double precision
  • Conversion between FP and 32bit signed integer

Known Issues

  • IR not passing. There's an issue with FPtoSI where when the input FP is out of range of integer, LLVM would return 0x80000000 but Altera core returns 0x79999999. If the value is used in operation such as division, the result becomes completely off.
  • In some of the cores, using the constant 0 directly would fail (using variable containing 0 is fine)
  • Scheduler will not schedule FP instruction every cycle even when there is no dependency
floating_point_support.txt · Last modified: 2012/10/04 22:44 by xiryan