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dc967a97df
port it to the new pass manager. All this does is extract the inner "location" class used by AA into its own full fledged type. This seems *much* cleaner as MemoryDependence and soon MemorySSA also use this heavily, and it doesn't make much sense being inside the AA infrastructure. This will also make it much easier to break apart the AA infrastructure into something that stands on its own rather than using the analysis group design. There are a few places where this makes APIs not make sense -- they were taking an AliasAnalysis pointer just to build locations. I'll try to clean those up in follow-up commits. Differential Revision: http://reviews.llvm.org/D10228 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239003 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))
//===---------------------------------------------------------------------===//