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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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