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--multiply_latency=cycles

7.112 --multiply_latency=cycles

Tells the compiler the number of cycles used by the hardware multiplier.

Syntax

--multiply_latency=cycles
Where cycles is the number of cycles used.

Usage

Use this option to tell the compiler how many cycles the MUL instruction takes to use the multiplier block and related parts of the chip. Until finished, these parts of the chip cannot be used for another instruction and the result of the MUL is not available for any later instructions to use.
It is possible that a processor might have two or more multiplier options that are set for a given hardware implementation. For example, one implementation might be configured to take one cycle to execute. The other implementation might take 33 cycles to execute. This option lets you convey the correct number of cycles for a given processor.

Default

The default number of cycles used by the hardware multiplier is processor-specific. See the Technical Reference Manual for the processor architecture you are compiling for.

Example

--multiply_latency=33
Related information
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