There is a problem in loop cache analysis that the types of SCEV variables
`Coeff` and `ElemSize` in function `isConsecutive()` may not match. The
mismatch would cause SCEV failures when `Coeff` is multiplied with `ElemSize`.
The fix in this patch is to extend the type of both `Coeff` and `ElemSize` to
whichever is wider in those two variables. As a clean-up, duplicate calculations
of `Stride` in `computeRefCost()` is then removed.
Reviewed By: Meinersbur, #loopoptwg
Differential Revision: https://reviews.llvm.org/D128877
In some passes we need a valid number of cache line size to do analysis or
transformation, e.g., loop cache analysis and loop date prefetch. However,
for some backend targets, `TTIImpl->getCacheLineSize()` is not implemented
and hence 'TTI.getCacheLineSize()' would just return 0 which eventually might
produce invalid result.
In this patch we add a user-specified opt/llc option for cache line size.
If the option is specified by users we use the value supplied, otherwise we
fall-back to the default value obtained from `TTIImpl->->getCacheLineSize()`.
The powerpc target already has such an option, this patch generalizes
this option to TargetTransformInfo.cpp.
Reviewed By: bmahjour, #loopoptwg
Differential Revision: https://reviews.llvm.org/D127342
Congzhe Cao