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IAR Embedded Workbench for RISC-V 3.40.x

ISA Extensions

In this section:

The ISA Extensions options specify support for some of the extensions to the RISC-V ISA.

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Cache management

Enables code generation with support for one or more of the CMO extensions. Choose from:

Zicbom

Generates code for the standard extension Zicbom (cache block management operations).

Zicbop

Generates code for the standard extension Zicbop (cache block prefetch operations).

Zicboz

Generates code for the standard extension Zicboz (cache block zero operations).

Xeswincache

Generates code for the non-standard extension Xeswincache (cache management to the RISC-V ISA).

Andes extensions

Select the Xandesperf option to generate code with support for the AndeStar™ V5 Performance instruction set extension.

Select the Xcodense option to generate code with support for the AndeStar™ V5 CoDense instruction set extension for code size compaction.

Select the Exclude JAL instruction option to exclude all call instructions from being candidates for replacement with exec.it instructions. (When CoDense code size compaction is used, call instruction pairs are normally used as candidates for being replaced with exec.it instructions during optimization in the linker. In some applications this can result in bad use of the CoDense table.)

DSP

Selects which DSP extension or extension subsets to generate code for. Choose between:

None

Generates code without support for any of the extensions for digital signal processing.

Xandesdsp

Generates code with support for the AndeStar™ DSP instruction set extension.

Xeswindsp

Generates code with support for the Eswin DSP extension. This corresponds to version 0.9.11 of the P extension, although some instructions use the encoding of version 0.9.6.

Xxldsp (Nuclei)

Generates code with support for the Nuclei DSP extension. This corresponds to version 0.5.4 of the P extension and the Xxldsp custom instructions.

P

Generates code with support for the Zpn and Zbpbo subsets of the P instruction set extension. Use the dropdown menu to specify the version.

Select the Zpsfoperand option to generate code with support for all P extension subsets (that is, also for the Zpsfoperand subset).