Commit Graph

6 Commits

Author SHA1 Message Date
Benjamin Kramer
7d4253af16 Follow up to 168711: It's safe to base this analysis on the found compare, just return the value for the right predicate.
Thanks to Andy for catching this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168921 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-29 19:07:57 +00:00
Benjamin Kramer
b2a818f83b SCEV: Even if the latch terminator is foldable we can't deduce the result of an unrelated condition with it.
Fixes PR14432.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168711 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-27 18:16:32 +00:00
Dan Gohman
c056454ecf Remove the Expr member from IVUsers. Instead of remembering the expression,
just ask ScalarEvolution for it on demand. This helps IVUsers be more robust
in the case of expressions changing underneath it. This fixes PR6862.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101819 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-19 21:48:58 +00:00
Dan Gohman
931e345e76 Re-apply r101000, with a fix: Don't eliminate an icmp which is part of
the loop exit test. This usually doesn't come up for a variety of
reasons, but it isn't impossible, so make IndVarSimplify handle it
conservatively.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101008 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-12 02:21:50 +00:00
Dan Gohman
ac3b9cdf15 Revert 101000, which is breaking self-host builds.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101002 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-12 00:17:10 +00:00
Dan Gohman
3fddbb337d Teach IndVarSimplify how to eliminate comparisons involving induction
variables. For example, with code like this:

  for (i=0;i<n;++i)
    if (i<n)
      x[i] = 0;

IndVarSimplify will now recognize that i is always less than n inside
the loop, and eliminate the if.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101000 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-11 23:10:12 +00:00