0007-Add-open-ended-comments.patch

[Maxim Kuvyrkov]

On 6/16/10 9:18 PM, Jeff Law wrote:
>> This patch adds several open-ended comments in gcse.c.  I'll be happy
>> if anyone can answer some of them, in which case I'll check in the
>> answers, rather than questions :).
>>
>> Thank you,
>>
> @@ -3431,7 +3431,9 @@ process_insert_insn (struct expr *expr)
>
> For PRE, we want to verify that the expr is either transparent
> or locally anticipatable in the target block. This check makes
> - no sense for code hoisting. */
> + no sense for code hoisting.
> + ??? We always call this function with (PRE == 0), which makes the checks
> + useless. */
> See pre_edge_insert and search for EDGE_ABNORMAL.
>
> That code went through several iterations and may no longer be
> necessary. So we really should extend the existing comment before the
> call to insert_insn_end_basic_block from pre_edge_insert.

I tried making pre_edge_insert to call insert_insn_end_basic_block with 
(pre == 1), and that failed with segmentation fault due to antloc being 
NULL.

Anyway, the attached patch removes unused checks.

OK to check in?

-- 
Maxim Kuvyrkov
CodeSourcery
maxim@codesourcery.com
(650) 331-3385 x724
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: 0009-Fix-call-to-insert_insn_end_basic_block.ChangeLog
URL: <http://gcc.gnu.org/pipermail/gcc-patches/attachments/20100623/08fe269b/attachment.ksh>
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: 0009-Fix-call-to-insert_insn_end_basic_block.patch
URL: <http://gcc.gnu.org/pipermail/gcc-patches/attachments/20100623/08fe269b/attachment-0001.ksh>