mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-12-15 04:30:12 +00:00
23aefe5e92
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83001 91177308-0d34-0410-b5e6-96231b3b80d8
19 lines
669 B
Plaintext
19 lines
669 B
Plaintext
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.
|
|
|
|
//===---------------------------------------------------------------------===//
|