This uses an int64_t-based fastpath for the common case and falls back to
SlowMPInt to handle the rare cases where larger numbers occur.
It uses `__builtin_*` for performance through the support in LLVM MathExtras.
Using this in the Presburger library results in a minor performance
*improvement* over any commit hash before sequence of patches
starting at d5e31cf38adfc2c240fb9717989792537cc9e819.
This was previously reverted in 1e10d35ea9c02e9b5694836fd3dcc0b9baf28b48 due
to a build failure; relanding now with an attempted fix.
Reviewed By: Groverkss, ftynse
Differential Revision: https://reviews.llvm.org/D128811
This uses an int64_t-based fastpath for the common case and falls back to
SlowMPInt to handle the rare cases where larger numbers occur.
It uses `__builtin_*` for performance through the support in LLVM MathExtras.
Using this in the Presburger library results in a minor performance
*improvement* over any commit hash before sequence of patches
starting at d5e31cf38adfc2c240fb9717989792537cc9e819.
Reviewed By: Groverkss, ftynse
Differential Revision: https://reviews.llvm.org/D128811
