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Re: 0005-Search-all-dominated-blocks-for-expressions-to-hoist.patch


On 06/30/10 09:26, Steven Bosscher wrote:
On Wed, Jun 30, 2010 at 5:11 PM, Jeff Law<law@redhat.com> wrote:
If there is a real issue here, the PRE approach is required for correctness.
  TRANSPOUT misses a boatload of stuff (Integer DIV/MOD, most FP operations,
etc).

What I'm struggling with is why we need this hair at all for hoisting since
we're not inserting on edges.
IIRC it has something to do with being unable to fixup the CFG if we
move a potentially throwing expression.
But there aren't any fixups to do -- the fixups are necessary when we insert on an abnormal edge. For hoisting that never happens.

jeff


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