From: Emanuele Giuseppe Esposito <e.emanuelegiuse...@gmail.com> Current documentation is not too clear on the GETPC usage. In particular, when used outside the top level helper function it causes unexpected behavior.
Signed-off-by: Emanuele Giuseppe Esposito <e.emanuelegiuse...@gmail.com> Message-id: 20201015095147.1691-1-e.emanuelegiuse...@gmail.com Reviewed-by: Peter Maydell <peter.mayd...@linaro.org> Signed-off-by: Peter Maydell <peter.mayd...@linaro.org> --- docs/devel/loads-stores.rst | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/docs/devel/loads-stores.rst b/docs/devel/loads-stores.rst index 9a944ef1af6..59c1225391c 100644 --- a/docs/devel/loads-stores.rst +++ b/docs/devel/loads-stores.rst @@ -93,7 +93,13 @@ guest CPU state in case of a guest CPU exception. This is passed to ``cpu_restore_state()``. Therefore the value should either be 0, to indicate that the guest CPU state is already synchronized, or the result of ``GETPC()`` from the top level ``HELPER(foo)`` -function, which is a return address into the generated code. +function, which is a return address into the generated code [#gpc]_. + +.. [#gpc] Note that ``GETPC()`` should be used with great care: calling + it in other functions that are *not* the top level + ``HELPER(foo)`` will cause unexpected behavior. Instead, the + value of ``GETPC()`` should be read from the helper and passed + if needed to the functions that the helper calls. Function names follow the pattern: -- 2.20.1
