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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