Fix uninit r2 in divmod_u32u32_unsafe and divmod_s32s32_unsafe #2760
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andylinpersonal
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When the ``divmod_s32s32_unsafe`` and ``divmod_u32u32_unsafe`` is called without enabled ``PICO_DIVIDER_DISABLE_INTERRUPTS``, ``ldr r2, =SIO_BASE`` will be bypassed. Later access to ``SIO_DIV`` will crash. Fixes raspberrypi#2773 Signed-off-by: Andy Lin <andylinpersonal@gmail.com>
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Contributor
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good spot; i think i'd probably want to extract the unsafe variants into their own code/section (I doubt they are that ocmmonly used) to avoid the extra 2 cycles in the common divide code path |
Author
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Maybe it's useful when used inside RTOS. In those case we can delegate the saving stuff to context-switch code. |
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When the
divmod_s32s32_unsafeanddivmod_u32u32_unsafeis called without enabled
PICO_DIVIDER_DISABLE_INTERRUPTS,ldr r2, =SIO_BASEwill be bypassed. Later access toSIO_DIVwill crash.
Fixes #2773