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IAR Embedded Workbench for Arm 9.70.x

‑‑use_optimized_variants

In this section:
Syntax
‑‑use_optimized_variants={no|auto|small|fast}
Parameters

no

Always uses the default variant with standard optimizations.

auto

Uses variants based on AEABI attributes that indicate the requested optimization goal:

If a module is compiled with -Ohs, and the DLIB library contains a fast variant of a function that is referenced in the module, that variant is used.

If all modules referencing a function are compiled with -Ohz, and the DLIB library contains a small variant of that function, that variant is used.

This is the default behavior of the linker.

small

Always uses a small variant (balances code size and execution speed, favoring size) if there is one in the DLIB library.

fast

Always uses a fast variant (maximum execution speed) if there is one in the DLIB library.

Description

Use this option to control the use of optimized variants of some DLIB library functions. (Some DLIB libraries delivered with the product contain optimized variants, such as a small integer division routing for Cortex-M0, or a fast strcpy implementation for cores that support the Thumb-2 ISA architecture.)

To see which variants that this option selected, inspect the list of redirects in the linker map file.

Caution

To set this option, use Project>Options>Linker>Extra Options.