kuba at gcc.gnu.org
Mon Nov 2 13:39:46 CST 2009
On Oct 12, 2009, at 2:27 AM, Chris Lattner wrote:
> On Oct 10, 2009, at 7:48 AM, Jakub Staszak wrote:
>> This patch fixes pr3707.
> Can you explain a little more what this does? What is the intuition
> behind disabling this optimization?
Oh, this patch is crap :( Sorry for this.
The problem is that we lack of optimization for case like:
%timeout.0 = phi i32 [ 2000, %loopto ], [ %timeout.0.ph,
Then something like "%reg<def> = MOV 2000" is inserted into loopto
block and executed every time. I haven't found any optimization which
can handle this and move instruction into some outer block.
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