Add the infrastructure for building and invoking a decodetree decoder
for the AArch32 Neon encodings. At the moment the new decoder covers
nothing, so we always fall back to the existing hand-written decode.
We follow the same pattern we did for the VFP decodetree conversion
(commit 78e138bc1f
and following): code that deals
with Neon will be moving gradually out to translate-neon.vfp.inc,
which we #include into translate.c.
In order to share the decode files between A32 and T32, we
split Neon into 3 parts:
* data-processing
* load-store
* 'shared' encodings
The first two groups of instructions have similar but not identical
A32 and T32 encodings, so we need to manually transform the T32
encoding into the A32 one before calling the decoder; the third group
covers the Neon instructions which are identical in A32 and T32.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200430181003.21682-4-peter.maydell@linaro.org
30 lines
1.2 KiB
Plaintext
30 lines
1.2 KiB
Plaintext
# AArch32 Neon load/store instruction descriptions
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#
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# Copyright (c) 2020 Linaro, Ltd
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#
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# This library is free software; you can redistribute it and/or
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# modify it under the terms of the GNU Lesser General Public
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# License as published by the Free Software Foundation; either
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# version 2 of the License, or (at your option) any later version.
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#
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# This library is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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# Lesser General Public License for more details.
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#
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# You should have received a copy of the GNU Lesser General Public
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# License along with this library; if not, see <http://www.gnu.org/licenses/>.
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#
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# This file is processed by scripts/decodetree.py
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#
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# Encodings for Neon load/store instructions where the T32 encoding
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# is a simple transformation of the A32 encoding.
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# More specifically, this file covers instructions where the A32 encoding is
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# 0b1111_0100_xxx0_xxxx_xxxx_xxxx_xxxx_xxxx
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# and the T32 encoding is
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# 0b1111_1001_xxx0_xxxx_xxxx_xxxx_xxxx_xxxx
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# This file works on the A32 encoding only; calling code for T32 has to
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# transform the insn into the A32 version first.
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