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;
; 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
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