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4 Lines ASM need help!
- Thread starter A380
- Start date
If I remember MIPS correctly...
-Shift-left t0 by 8 bits and store in t1
-Shift-left t0 by 2 bits and store in t2
t1 should now have 256 * t0 and t2 has 4 * t0
-Add t1 and t2 and store in t3
t3 now has 260 * t0
-Add t3 and t0 and store in t0
t0 now has 261 * t0's original value
-Shift-left t0 by 8 bits and store in t1
-Shift-left t0 by 2 bits and store in t2
t1 should now have 256 * t0 and t2 has 4 * t0
-Add t1 and t2 and store in t3
t3 now has 260 * t0
-Add t3 and t0 and store in t0
t0 now has 261 * t0's original value
- Joined
- Oct 31, 2001
The point of using shifts rather than multiplies is that they are faster than multiplies. Only problem is you can only use them to multiply by a base 2 number, iirc.
On x86 at least, a multiply is supposed to be a loop of addition. So it could use alot of cycles. While shifting is just shoving a few bits around.
On x86 at least, a multiply is supposed to be a loop of addition. So it could use alot of cycles. While shifting is just shoving a few bits around.
