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b2ec2bd1f6
for VectorizeTree() API.This API uses it for proper mask computation to be used in shufflevector IR. The fix is to compute the mask for out of order memory accesses while building the vectorizable tree instead of actual vectorization of vectorizable tree. Reviewers: mkuper Differential Revision: https://reviews.llvm.org/D30159 Change-Id: Id1e287f073fa4959713ba545fa4254db5da8b40d git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296575 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))
//===---------------------------------------------------------------------===//