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Side-quest in the gcc/m88k work: on 88100, the DIV instruction is expensive (38 cycles). It is a bit less expensive on the 88110 (18 cycles), but still a heavy cost compared to other instructions.

Gcc has logic to try and replace a divide by a constant, by a multiplication by its inverse in a Z/2**NZ ring if a proper N can be found. In other words, instead of dividing, it will multiply by a large number, and shift the result to the right by 32 bits.

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