This patch changes the layout of DoubleAPFloat, and adjust all
operations to do either:
- (IEEEdouble, IEEEdouble) -> (uint64_t, uint64_t) -> PPCDoubleDoubleImpl, then run the old algorithm.
- Do the right thing directly.
- includes multiply, divide, remainder, mod, fusedMultiplyAdd, roundToIntegral, convertFromString, next, convertToInteger, convertFromAPInt, convertFromSignExtendedInteger, convertFromZeroExtendedInteger, convertToHexString, toString, getExactInverse.
- includes makeZero, makeLargest, makeSmallest, makeSmallestNormalized, compare, bitwiseIsEqual, bitcastToAPInt, isDenormal, isSmallest, isLargest, isInteger, ilogb, scalbn, frexp, hash_value, Profile.
I could split this into two patches, e.g. use
- for all operatoins first, then incrementally change some of them to
2). I didn't do that, because 1) involves code that converts data between
PPCDoubleDoubleImpl and (IEEEdouble, IEEEdouble) back and forth, and may
pessimize the compiler. Instead, I find easy functions and use
approach 2) for them directly.
Next step is to implement move multiply and divide from 1) to 2). I don't
have plans for other functions in 1).