Re: [PATCH 11/29] [arm] Reduce cost of insns that are simple reg-reg moves.

2019-10-22 Thread Richard Earnshaw (lists)
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

Re: [PATCH 11/29] [arm] Reduce cost of insns that are simple reg-reg moves.

2019-10-21 Thread Segher Boessenkool
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

Re: [PATCH 11/29] [arm] Reduce cost of insns that are simple reg-reg moves.

2019-10-21 Thread Richard Earnshaw (lists)
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

Re: [PATCH 11/29] [arm] Reduce cost of insns that are simple reg-reg moves.

2019-10-19 Thread Segher Boessenkool
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:

[PATCH 11/29] [arm] Reduce cost of insns that are simple reg-reg moves.

2019-10-18 Thread Richard Earnshaw
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