if-conversion/HOT-COLD partitioning

[Christophe Lyon]

On 23 October 2012 19:45, Steven Bosscher <stevenb.gcc@gmail.com> wrote:
> Christophe wrote:
>> I think merge_blocks() should be modified to handle such cases;
>
> I think can_merge_blocks should be fixed. Blocks from different
> partitions should not be merged. See cfgrtl.c:rtl_can_merge_blocks and
> cfgrtl.c:cfg_layout_can_merge_blocks_p. Why are they not blocking
> these blocks from getting merged?
>

Well, both of these functions appear to check that the 2 blocks to
merge belong to the same partition, so it should be OK.

But not all calls to merge_blocks are guarded by if
(can_merge_block_p()), this is probably where the problem is?

Christophe.