search for: sextw_r

...s this: ********** REWRITING TWO-ADDR INSTRS ********** ********** Function: sext %reg1028<def> = sextb_r %reg1025<kill> prepend: %reg1028<def> = mov_rr %reg1025<kill> rewrite to: %reg1028<def> = sextb_r %reg1028 ... %reg1030<def> = sextw_r %reg1026<kill> prepend: %reg1030<def> = mov_rr %reg1026<kill> rewrite to: %reg1030<def> = sextw_r %reg1030 Because sextb_r and sextw_r have destination tied to source operands, TwoAddressInstructionPass thinks it needs a copy. However, since the sext...

...TWO-ADDR INSTRS ********** > ********** Function: sext > %reg1028<def> = sextb_r %reg1025<kill> > prepend: %reg1028<def> = mov_rr %reg1025<kill> > rewrite to: %reg1028<def> = sextb_r %reg1028 > ... > %reg1030<def> = sextw_r %reg1026<kill> > prepend: %reg1030<def> = mov_rr %reg1026<kill> > rewrite to: %reg1030<def> = sextw_r %reg1030 > > Because sextb_r and sextw_r have destination tied to source operands, > TwoAddressInstructionPass thinks it needs a copy....

On Apr 19, 2009, at 6:15 PM, Greg McGary wrote: > > Because sextb_r and sextw_r have destination tied to source operands, > TwoAddressInstructionPass thinks it needs a copy. However, since the > sext kills its source, the copy is unnecessary. Why does this happen? > Is TwoAddressInstructionPass relying on a later pass to notice this > and > transform it agai...

Dan Gohman wrote: > On Apr 19, 2009, at 6:15 PM, Greg McGary wrote: > >> Because sextb_r and sextw_r have destination tied to source operands, >> TwoAddressInstructionPass thinks it needs a copy. However, since the >> sext kills its source, the copy is unnecessary. Why does this happen? >> Is TwoAddressInstructionPass relying on a later pass to notice this >> and >&g...

On Apr 21, 2009, at 4:02 PM, Greg McGary wrote: > Dan Gohman wrote: >> On Apr 19, 2009, at 6:15 PM, Greg McGary wrote: >> >>> Because sextb_r and sextw_r have destination tied to source >>> operands, >>> TwoAddressInstructionPass thinks it needs a copy. However, since >>> the >>> sext kills its source, the copy is unnecessary. Why does this >>> happen? >>> Is TwoAddressInstructionPass rel...