The recently imported cloudabi_vdso_armv6_on_64bit.S should be the vDSO
for 32-bit processes when being run on FreeBSD/arm64. This vDSO ensures
that all system call arguments are padded to 64 bits, so that they can
be used by the kernel to call into most of the native implementations
directly.
Make armv7 as a new MACHINE_ARCH.
Copy all the places we do armv6 and add armv7 as basically an
alias. clang appears to generate code for armv7 by default. armv7 hard
float isn't supported by the the in-tree gcc, so it hasn't been
updated to have a new default.
Support armv7 as a new valid MACHINE_ARCH (and by extension
TARGET_ARCH).
Add armv7 to the universe build.
Differential Revision: https://reviews.freebsd.org/D12010
Now that all of the necessary bits for ARMv6 support for CloudABI have
been checked in, let's hook the kernel module up to the build and
document its existence.
When fixing this module to build on PC98, I actually broke the build on
ARM64. On PC98 we need to pull in the sources from the MACHINE_CPUARCH
(i386), but on ARM64 we need to use the MACHINE, as MACHINE_CPUARCH is
set to aarch64 instead of just arm64.
Where the cloudabi64 kernel can be used to execute 64-bit CloudABI
binaries, this one should be used for 32-bit binaries. Right now it
works on i386 and amd64.
