Optimize mr. X, X after some instructions.

For example, when ncg emits
    slw r9,r8,r5
    mr. r9,r9
then top simplifies the code to
    slw. r9,r8,r5
This commit is contained in:
George Koehler 2017-12-22 22:32:16 -05:00
parent c964eeddba
commit 5f2a7b260f
2 changed files with 29 additions and 9 deletions

View file

@ -348,7 +348,7 @@ INSTRUCTIONS
or GPR:wo, GPR:ro, GPR:ro.
mr GPR:wo, GPR:ro.
orX "or." GPR:wo:cc, GPR:ro, GPR:ro.
orX_readonly "or." GPR:ro:cc, GPR:ro, GPR:ro.
mrX_readonly "mr." GPR:ro:cc, GPR:ro.
orc GPR:wo, GPR:ro, GPR:ro.
ori GPR:wo, GPR:ro, CONST+LABEL_LO:ro.
oris GPR:wo, GPR:ro, CONST:ro.
@ -707,15 +707,12 @@ MOVES
TESTS
/* Given orX %1, %1, %1, ncgg says, "Instruction destroys %1,
* not allowed here". We use orX_readonly to trick ncgg.
*
* Using "or." and not "mr." because mach/powerpc/top/table
* was optimizing "or." and not "mr.".
/* Given "mrX %1, %1", ncgg would say, "Instruction destroys
* %1, not allowed here". We use mrX_readonly to trick ncgg.
*/
to test GPR
gen
orX_readonly %1, %1, %1
mrX_readonly %1, %1
STACKINGRULES

View file

@ -1,5 +1,5 @@
/* PowerPC desciptor table for ACK target optimizer */
/* PowerPC table for ACK target optimizer */
MAXOP 3;
LABEL_STARTER '.';
@ -16,10 +16,33 @@ X, Y, Z { TRUE };
addi RNZ, RNZ, 0 -> ;
addis RNZ, RNZ, 0 -> ;
or X, Y, Y -> mr X, Y ;
or. X, Y, Y -> mr. X, Y ;
mr X, X -> ;
fmr X, X -> ;
or X, Y, Z : or. X, X, X -> or. X, Y, Z ;
add X, Y, Z : mr. X, X -> add. X, Y, Z ;
and X, Y, Z : mr. X, X -> and. X, Y, Z ;
andc X, Y, Z : mr. X, X -> andc. X, Y, Z ;
divw X, Y, Z : mr. X, X -> divw. X, Y, Z ;
divwu X, Y, Z : mr. X, X -> divwu. X, Y, Z ;
extsb X, Y, Z : mr. X, X -> extsb. X, Y, Z ;
extsh X, Y, Z : mr. X, X -> extsh. X, Y, Z ;
eqv X, Y, Z : mr. X, X -> eqv. X, Y, Z ;
mullw X, Y, Z : mr. X, X -> mullw. X, Y, Z ;
nand X, Y, Z : mr. X, X -> nand. X, Y, Z ;
nor X, Y, Z : mr. X, X -> nor. X, Y, Z ;
or X, Y, Z : mr. X, X -> or. X, Y, Z ;
orc X, Y, Z : mr. X, X -> orc. X, Y, Z ;
slw X, Y, Z : mr. X, X -> slw. X, Y, Z ;
slwi X, Y, Z : mr. X, X -> slwi. X, Y, Z ;
subf X, Y, Z : mr. X, X -> subf. X, Y, Z ;
sraw X, Y, Z : mr. X, X -> sraw. X, Y, Z ;
srawi X, Y, Z : mr. X, X -> srawi. X, Y, Z ;
srw X, Y, Z : mr. X, X -> srw. X, Y, Z ;
srwi X, Y, Z : mr. X, X -> srwi. X, Y, Z ;
xor X, Y, Z : mr. X, X -> xor. X, Y, Z ;
b X : labdef X -> labdef X ;