Files
llvm/lib/Analysis
Chandler Carruth 2aaf7228e0 [TI removal] Make variables declared as TerminatorInst and initialized
by `getTerminator()` calls instead be declared as `Instruction`.

This is the biggest remaining chunk of the usage of `getTerminator()`
that insists on the narrow type and so is an easy batch of updates.
Several files saw more extensive updates where this would cascade to
requiring API updates within the file to use `Instruction` instead of
`TerminatorInst`. All of these were trivial in nature (pervasively using
`Instruction` instead just worked).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344502 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-15 10:04:59 +00:00
..
2016-08-25 01:29:55 +00:00
2018-07-30 19:41:25 +00:00
2018-05-14 12:53:11 +00:00
2018-07-30 19:41:25 +00:00
2018-07-30 19:41:25 +00:00
2018-08-30 18:37:18 +00:00
2018-07-22 20:04:42 +00:00

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))

//===---------------------------------------------------------------------===//