Cycle Timings and Interlock Behavior

 

Table 14-1 Definition of cycle timing terms (continued)

 

 

Term

Description

 

 

Early Reg

The specified registers are required at the start of the Ex1 stage. Add one cycle to the Result Latency

 

of the instruction producing this register.

 

 

Very Early Reg

The specified registers are required at the start of the Iss stage. Add two cycles to the Result Latency

 

of the instruction producing this register, or one cycle if the instruction producing this register is an LDM,

 

LDR, LDRD, LDREX, or LDRT. The lower Result Latency does not apply if this register is the base register of

 

the load instruction producing this register, or if the load instruction is an LDRB, LDRBT, LDRH, LDRSB, or

 

LDRSH.

 

 

Interlock

There is a data dependency between two instructions in the pipeline, resulting in the Iss stage being

 

stalled until the processor resolves the dependency.

 

 

14.1.5Assembler language syntax

The syntax used throughout this chapter is unified assembler and the timings apply to ARM and Thumb instructions.

ARM DDI 0363E

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ARM R4F, r1p3 manual Assembler language syntax