mirror of https://gitee.com/openkylin/linux.git
39 lines
679 B
ArmAsm
39 lines
679 B
ArmAsm
|
;
|
||
|
|
; mulsi3 for H8/300H - based on Renesas SH implementation
|
||
|
|
;
|
||
|
|
; by Toshiyasu Morita
|
||
|
|
;
|
||
|
|
; Old code:
|
||
|
|
;
|
||
|
|
; 16b * 16b = 372 states (worst case)
|
||
|
|
; 32b * 32b = 724 states (worst case)
|
||
|
|
;
|
||
|
|
; New code:
|
||
|
|
;
|
||
|
|
; 16b * 16b = 48 states
|
||
|
|
; 16b * 32b = 72 states
|
||
|
|
; 32b * 32b = 92 states
|
||
|
|
;
|
||
|
|
|
||
|
|
.global __mulsi3
|
||
|
|
__mulsi3:
|
||
|
|
mov.w r1,r2 ; ( 2 states) b * d
|
||
|
|
mulxu r0,er2 ; (22 states)
|
||
|
|
|
||
|
|
mov.w e0,r3 ; ( 2 states) a * d
|
||
|
|
beq L_skip1 ; ( 4 states)
|
||
|
|
mulxu r1,er3 ; (22 states)
|
||
|
|
add.w r3,e2 ; ( 2 states)
|
||
|
|
|
||
|
|
L_skip1:
|
||
|
|
mov.w e1,r3 ; ( 2 states) c * b
|
||
|
|
beq L_skip2 ; ( 4 states)
|
||
|
|
mulxu r0,er3 ; (22 states)
|
||
|
|
add.w r3,e2 ; ( 2 states)
|
||
|
|
|
||
|
|
L_skip2:
|
||
|
|
mov.l er2,er0 ; ( 2 states)
|
||
|
|
rts ; (10 states)
|
||
|
|
|
||
|
|
.end
|