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[design docs] Remove ILP32 Support #416

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14 changes: 7 additions & 7 deletions design-documents/pauthabi-tls.rst
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Original file line number Diff line number Diff line change
Expand Up @@ -28,11 +28,11 @@ TLS Dialect
The base ABI in `AAELF64`_ defines relocations for two TLS
dialects. The "traditional" dialect and the "descriptor" dialect. In
the traditional dialect global and local dynamic TLS use the
``R_<CLS>_TLSGD``, ``R_<CLS>_TLSLD`` prefixed relocations. These
create a pair of GOT entries relocated by ``R_<CLS>_TLS_DTPMOD`` and
``R_<CLS>_TLS_DTPREL``. In the "descriptor" dialect, global and local
dynamic TLS use the ``R_<CLS>_TLSDESC`` prefixed relocations. These
create a pair of GOT entries relocated by ``R_<CLS>_TLSDESC``. Local
``R_AARCH64_TLSGD``, ``R_AARCH64_TLSLD`` prefixed relocations. These
create a pair of GOT entries relocated by ``R_AARCH64_TLS_DTPMOD`` and
``R_AARCH64_TLS_DTPREL``. In the "descriptor" dialect, global and local
dynamic TLS use the ``R_AARCH64_TLSDESC`` prefixed relocations. These
create a pair of GOT entries relocated by ``R_AARCH64_TLSDESC``. Local
Exec and Initial Exec TLS are handled the same way in both dialects.

The `PAUTHABIELF64`_ only supports the descriptor based dialect,
Expand All @@ -58,13 +58,13 @@ At present there are AUTH variant static and dynamic relocations
defined for TLSDESC, but not for Initial Exec.

Local dynamic TLS does not use the GOT so it can be handled by the
``R_<CLS>_TLSLE`` prefixed relocations from the base ABI defined in
``R_AARCH64_TLSLE`` prefixed relocations from the base ABI defined in
`AAELF64`_.

The choice of which GOT entries to sign is a property of the
signing-schema for the platform. For example a signing-schema may only
sign GOT entries containing code-pointers, which would permit Initial
Exec TLS using the ``R_<CLS>_TLSIE`` prefixed relocations defined in
Exec TLS using the ``R_AARCH64_TLSIE`` prefixed relocations defined in
`AAELF64`_. Alternatively a signing-schema may sign all GOT entries,
which would require AUTH variant static and dynamic relocations to be
defined for Initial Exec.
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