Question for powerpc64 lib32 (powerpc) support: what ABI is the powerpc code supposed to be using?

[Mark Millard]

powerpc64 and powerpc have very different stack handling
rules for FreeBSD. As an example, powerpc does not require
red-zones for signal handling in the kernel but powerpc64
does.

For lib32 support, what ABI is the powerpc code supposed
to follow in the powerpc64 environment? What style of
stack handling (and related register usage) is supposed
to be in use? If it is distinct from powerpc native's
ABI, what documentation should be looked at for the ABI?

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Mark Millard
markmi at dsl-only.net