This commit adds the ability to compile native modules for the RV64
platform, using "rv64imc" as its architecture name (eg.
"make ARCH=rv64imc" should build a RV64 natmod).
The rest of 64-bits relocations needed to build a native module are now
implemented, and all sample native modules build without errors or
warnings. The same Picolibc caveats on RV32 also apply on RV64, thus
the documentation was updated accordingly.
RV64 native modules are also built as part of the CI process, but not
yet executed as the QEMU port is not yet able to load and run them.
Signed-off-by: Alessandro Gatti <a.gatti@frob.it>
This commit provides the appropriate external symbol addresses to let
the "framebuf" example natmod build for the Xtensa platform.
On the ESP8266, integer division code isn't provided as part of
libgcc.a, libm.a, or libc.a, but it is instead provided by the ROM.
Regular builds inject the appropriate symbol addresses as part of the
linking process (see eagle.rom.addr.v6.ld), but natmods need this
information brought in from somewhere else.
Signed-off-by: Alessandro Gatti <a.gatti@frob.it>
