Hi Richard,
在 2023/3/16 15:57, Richard Biener 写道:
> I'm not sure if careful constraints massaging like adding magic letters to
> alternatives with constants to pessimize them for LRA, making them
> more expensive than spilling the constant to a register but avoid
> secondary reloads with spilling
Hi Richard,
在 2023/3/16 18:36, Richard Biener 写道:
> On Thu, Mar 16, 2023 at 10:04 AM HAO CHEN GUI wrote:
>>
>> Hi Richard,
>>
>> 在 2023/3/16 15:57, Richard Biener 写道:
>>> So this is one way around the lack of CSE/PRE of constant operands. I'd
>>> argue that a better spot for this _might_ be LRA
On Thu, Mar 16, 2023 at 10:04 AM HAO CHEN GUI wrote:
>
> Hi Richard,
>
> 在 2023/3/16 15:57, Richard Biener 写道:
> > So this is one way around the lack of CSE/PRE of constant operands. I'd
> > argue that a better spot for this _might_ be LRA (split the constant out if
> > there's a free register av
Hi Richard,
在 2023/3/16 15:57, Richard Biener 写道:
> So this is one way around the lack of CSE/PRE of constant operands. I'd
> argue that a better spot for this _might_ be LRA (split the constant out if
> there's a free register available), postreload-[g]cse (CSE the constants) and
> then maybe cp
On Thu, Mar 16, 2023 at 6:35 AM HAO CHEN GUI via Gcc-patches
wrote:
>
> Hi,
> Currently, rs6000 directly expands to 2 insns if an integer constant is the
> second operand and it needs two insns. For example, addi/addis and ori/oris.
> It may not benefit when the constant is used for more than 2
Hi,
Currently, rs6000 directly expands to 2 insns if an integer constant is the
second operand and it needs two insns. For example, addi/addis and ori/oris.
It may not benefit when the constant is used for more than 2 times in an
extended basic block, just like the case in PR shows.
One possib
