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896f064a49
folding the code into the main Analysis library. There already wasn't much of a distinction between Analysis and IPA. A number of the passes in Analysis are actually IPA passes, and there doesn't seem to be any advantage to separating them. Moreover, it makes it hard to have interactions between analyses that are both local and interprocedural. In trying to make the Alias Analysis infrastructure work with the new pass manager, it becomes particularly awkward to navigate this split. I've tried to find all the places where we referenced this, but I may have missed some. I have also adjusted the C API to continue to be equivalently functional after this change. Differential Revision: http://reviews.llvm.org/D12075 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@245318 91177308-0d34-0410-b5e6-96231b3b80d8
Analysis Opportunities:
//===---------------------------------------------------------------------===//
In test/Transforms/LoopStrengthReduce/quadradic-exit-value.ll, the
ScalarEvolution expression for %r is this:
{1,+,3,+,2}<loop>
Outside the loop, this could be evaluated simply as (%n * %n), however
ScalarEvolution currently evaluates it as
(-2 + (2 * (trunc i65 (((zext i64 (-2 + %n) to i65) * (zext i64 (-1 + %n) to i65)) /u 2) to i64)) + (3 * %n))
In addition to being much more complicated, it involves i65 arithmetic,
which is very inefficient when expanded into code.
//===---------------------------------------------------------------------===//
In formatValue in test/CodeGen/X86/lsr-delayed-fold.ll,
ScalarEvolution is forming this expression:
((trunc i64 (-1 * %arg5) to i32) + (trunc i64 %arg5 to i32) + (-1 * (trunc i64 undef to i32)))
This could be folded to
(-1 * (trunc i64 undef to i32))
//===---------------------------------------------------------------------===//