Cycle Timings and Interlock Behavior

Table 14-9 Example multiply instruction cycle timing behavior (continued)

Example

Cycles

Early Reg

Late Reg

Result latency

instruction

 

 

 

 

 

 

 

 

 

SMLALD, SMLALDX

1

<Rn>, <Rm>

-

2, 2

 

 

 

 

 

SMLSLD, SMLSLDX

1

<Rn>, <Rm>

-

2, 2

 

 

 

 

 

UMAAL

2

<Rn>, <Rm>

<RdLo>, <RdHi>

3, 3

 

 

 

 

 

Note

Result Latency is one less if the result is used as the accumulate value for a subsequent multiply accumulate. This only applies if the result is the same width as the accumulate value, that is 32 or 64 bits.

ARM DDI 0363E

Copyright © 2009 ARM Limited. All rights reserved.

14-13

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