[RFA][PATCH][PR middle-end/59285] BARRIERS and merged blocks
Wed Jan 8 05:54:00 GMT 2014
On 01/07/14 01:08, Steven Bosscher wrote:
> On Tuesday, January 7, 2014, Jeff Law wrote:
> On 12/24/13 13:19, Steven Bosscher wrote:
> For GCC 4.10
> we should define what behavior should result from
> (Should it trap? Can it be optimized away after a while to avoid
> unnecessary conditional jumps? ...) but for the moment it seems
> IMHO to only optimize this in the cond_exec case and to do so
> the rules of the control flow graph.
> This problem can (and should) be addressed independently of a review
> of the __builtin_unreachable semantics.
> Something like the patch below, tested with a cross-compiler for
> What do you think of this approach?
> PR middle-end/59285
> * ifcvt. (cond_exec_find_if_block): Do not try to
> if-convert an empty
> basic block without successors due to builtin_unreachable.
> I still prefer my most recent patch.
Thanks. One more P1 off the list :-)
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