Extension Instruction Specifications
3-35
(d) Note on the description of multiply-and-accumulate instructions and multiply-and-accumulate instructions or
multiply-and-accumulate instructions and quick multiplication instructions
When executing a multiply-and-accumulate instruction followed by another multiply-and-accumulate instruction
or a quick multiplication instruction, at least three cycles must be inserted between the instructions. However, no
problems are encountered in the case of the instruction combinations listed in the table, or when the value of the
multiply-and-accumulate operation overflow detect register MCVF is not used.
Preceding instruction Following instruction
MAC or MACH MAC or MACH
MACU or MACHU MACU or MACHU
MACB MACB
MACBU MACBU
This note applies to the following instructions (except in the case of the instruction combinations listed above):
<Multiply-and-accumulate instructions>
MAC instruction, MACH instruction, MACU instruction, MACHU instruction
MACB instruction, MACBU instruction,
<High-speed multiplication instructions>
MULQ instruction, MULQU instruction, MULQI instruction, MULQIU instruction