[PR debug/46782] Skip debug insns in try_forward_edges

[Alexandre Oliva]

On Dec  8, 2010, Richard Guenther <richard.guenther@gmail.com> wrote:

> On Wed, Dec 8, 2010 at 5:06 AM, Alexandre Oliva <aoliva@redhat.com> wrote:
>> At -O0, we merge blocks or not depending on locus information present at
>> the last insn in a block and the entry locus of the subsequent block.
>> We shouldn't use the locus of a debug insn for this compare, lest we may
>> end up not merging blocks that, with -g0, we would.
>> 
>> This seldom occurs in practice, since this patch is only active at -O0,
>> and -fvar-tracking is disabled by default at -O0, even if -g is enabled.
>> However, since it's possible to explicitly activate -fvar-tracking (and
>> -fvar-tracking-assignments), even at -O0, we shouldn't generate
>> different executable code if the user does this.
>> 
>> The patch below was regstrapped on x86_64-linux-gnu.  Ok to install?

> Ok.

A few tweaks were needed for 4.5.  Regstrapped on x86_64-linux-gnu,
along with the patch for PR 46576 (unchanged).  I'll apply both in the
4.5 branch if there aren't objections within 20 hours or so, so that the
bug reports can be closed.

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Alexandre Oliva, freedom fighter    http://FSFLA.org/~lxoliva/
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