Commit Graph

4 Commits

Author SHA1 Message Date
Dan Gohman e637ff5e9a 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.

llvm-svn: 101819
2010-04-19 21:48:58 +00:00
Dan Gohman fa5ad797e3 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.

llvm-svn: 101008
2010-04-12 02:21:50 +00:00
Dan Gohman c0f1efaf8d Revert 101000, which is breaking self-host builds.
llvm-svn: 101002
2010-04-12 00:17:10 +00:00
Dan Gohman af4ab1b681 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.

llvm-svn: 101000
2010-04-11 23:10:12 +00:00