This is the documentation for the latest (main) development branch of Zephyr. If you are looking for the documentation of previous releases, use the drop-down menu on the left and select the desired version.

CONFIG_ASSEMBLER_ISA_THUMB2

(No prompt – not directly user assignable.)

Type: bool

Help

This helper symbol specifies the default target instruction set for
the assembler.

When only the Thumb-2 ISA is supported (i.e. on Cortex-M cores), the
assembler must use the Thumb-2 instruction set.

When both the Thumb-2 and ARM ISAs are supported (i.e. on Cortex-A
and Cortex-R cores), the assembler must use the ARM instruction set
because the architecture assembly code makes use of the ARM
instructions.

Direct dependencies

!ISA_ARM && ARM

(Includes any dependencies from ifs and menus.)

Default

Kconfig definition

At arch/arm/core/aarch32/Kconfig:78

Included via Kconfig:8Kconfig.zephyr:37arch/Kconfig:12arch/arm/Kconfig:57

Menu path: (Top) → ARM Options

config ASSEMBLER_ISA_THUMB2
    bool
    default y if ISA_THUMB2 && !ISA_ARM
    depends on !ISA_ARM && ARM
    help
      This helper symbol specifies the default target instruction set for
      the assembler.

      When only the Thumb-2 ISA is supported (i.e. on Cortex-M cores), the
      assembler must use the Thumb-2 instruction set.

      When both the Thumb-2 and ARM ISAs are supported (i.e. on Cortex-A
      and Cortex-R cores), the assembler must use the ARM instruction set
      because the architecture assembly code makes use of the ARM
      instructions.

(The ‘depends on’ condition includes propagated dependencies from ifs and menus.)