Commit d8f186aa4a ("arch: common: semihost: add semihosting
operations") encapsulated semihosting invocation in a per-arch
semihost_exec() function. There is a fixed register variable declaration
for the return value but this variable is not listed as an output
operand to respective inline assembly segments which is an error.
This is not reported as such by gcc and the generated code is still OK
in those particular instances but this is not guaranteed, and clang
does complain about such cases.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Add an API that utilizes the ARM semihosting mechanism to interact with
the host system when a device is being emulated or run under a debugger.
RISCV is implemented in terms of the ARM implementation, and therefore
the ARM definitions cross enough architectures to be defined 'common'.
Functionality is exposed as a separate API instead of syscall
implementations (`_lseek`, `_open`, etc) due to various quirks with
the ARM mechanisms that means function arguments are not standard.
For more information see:
https://developer.arm.com/documentation/dui0471/m/what-is-semihosting-
Signed-off-by: Jordan Yates <jordan.yates@data61.csiro.au>
impl
