On 03/31/2011 11:16 PM, Tom de Vries wrote:
> On 03/31/2011 08:52 PM, Jeff Law wrote:
> 
>> On 03/31/11 12:42, Tom de Vries wrote:
>>> Uses regnotes to analyze whether we can replace insn a by insn b, even
>>> if we cannot replace insn b by insn a. Uses this info in crossjumping.
> 
>> Shouldn't this be using single_set rather than digging through PATTERN,
>> then verifying both are SETs, etc.?
>>
>> Otherwise don't you miss most of the benefit on architectures where most
>> insns clobber the flags register in a PARALLEL with the SET?
> 
> I see what you mean about missing these insns currently.
> 
> I guess I will have to check that the non-SET part of the PARALLEL is
> identical between the 2 insns.
> 
> I'll update the patch to handle this case.

changes compared to previous posting:
- add ChangeLog.
- use single_set
- add equal_different_set_p and use it in can_replace_by

Retested on x86_64.

Thanks,
- Tom