5.3.1 BranchPrediction parameters

This section describes the parameters for the BranchPrediction plug-in.

Each parameter is prefixed with BranchPrediction.BranchPrediction, for example:

BranchPrediction.BranchPrediction.bpstat-branchcount

Table 5-2 BranchPrediction parameters

Name Type Default value Allowed values Runtime Description
bpstat-branchcount int -0x1 0x0 - 0x7fffffffffffffff false The number of branch data to display. Set to -1 to display all branch instructions.
bpstat-pathfilename string - - false The path and filename of the branch statistics log, relative to the current directory. If you omit it, no log file is generated.
mispredict-latency int 0x8 0x0 - 0x7fffffffffffffff false

The number of instructions that are flushed for every misprediction.

It is equal to the pipeline length of the processor. For example, in a processor where the prefetch unit has three stages and the execution units have five stages, the pipeline length is eight. Therefore the mispredict-latency is eight clock cycles.

predictor-type string "CortexA53Predictor" See the note following the table. false The type of branch predictor to use.

Note:

predictor-type can be one of the following example branch predictors that Arm provides, or a user-defined one:

FixedDirectionPredictor
An example predictor that always takes a preset fixed direction.
BiModalPredictor
An example of a standard 2-bit strength predictor.
GSharePredictor
An example of a standard global history sharing predictor.
HybridPredictor
An example predictor that selects the majority result from the bimodal predictor, fixed-direction predictor, and a random predictor.
CortexA53Predictor
Cortex®‑A53 branch predictor. This is the default.
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