On 21/10/2019 16:46, Richard Earnshaw (lists) wrote:
On 19/10/2019 17:17, Segher Boessenkool wrote:
Yes, but combine should have removed the move in a 2->1 combination
already, if it is beneficial: both 18->7 and 7->22 should have combined
just fine. This also points to a potential target
On Mon, Oct 21, 2019 at 04:46:47PM +0100, Richard Earnshaw (lists) wrote:
> On 19/10/2019 17:17, Segher Boessenkool wrote:
> >Maybe we should simply disallow pseudo-to-pseudo (or even all) copies when
> >combining more than two insns, always? I'll experiment.
> For the 2-insn case we don't try a
On 19/10/2019 17:17, Segher Boessenkool wrote:
On Fri, Oct 18, 2019 at 08:48:42PM +0100, Richard Earnshaw wrote:
Consider this sequence during combine:
Trying 18, 7 -> 22:
18: r118:SI=r122:SI
REG_DEAD r122:SI
7: r114:SI=0x1-r118:SI-ltu(cc:CC_RSB,0)
REG_DEAD r118:SI
On Fri, Oct 18, 2019 at 08:48:42PM +0100, Richard Earnshaw wrote:
>
> Consider this sequence during combine:
>
> Trying 18, 7 -> 22:
>18: r118:SI=r122:SI
> REG_DEAD r122:SI
> 7: r114:SI=0x1-r118:SI-ltu(cc:CC_RSB,0)
> REG_DEAD r118:SI
> REG_DEAD cc:CC_RSB
>22:
Consider this sequence during combine:
Trying 18, 7 -> 22:
18: r118:SI=r122:SI
REG_DEAD r122:SI
7: r114:SI=0x1-r118:SI-ltu(cc:CC_RSB,0)
REG_DEAD r118:SI
REG_DEAD cc:CC_RSB
22: r1:SI=r114:SI
REG_DEAD r114:SI
Failed to match this instruction:
(set (reg:SI 1 r1 [+4