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Re: [PATCH] Merging BB and user labels (tree level)


On Dec 29, 2004, at 5:12 PM, Jeffrey A Law wrote:

On Wed, 2004-12-29 at 16:35 -0500, Andrew Pinski wrote:
On Dec 29, 2004, at 3:59 PM, Jeffrey A Law wrote:

On Thu, 2004-12-16 at 23:46 -0500, Andrew Pinski wrote:
As much as I'd like to move forward with this patch, I think it is
broken.

Consider an unreferenced user label. 

Then why at -O2 I get the labels moved to the beginning of the BB
for the following testcase:
int i, d = 10, e = 10;
int main(void)
{
  L:
   i++;
  L1:
   i+=d;
  L2:
   i*=e;
}

I don't know offhand.  You've have to analyze why the two testcases
differ in their behavior.


Actually your testcase also does the same thing at -O2.
Now at -O1, they both keep the labels at the same spot as the source.

-- Pinski

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