Commit Graph

7 Commits

Author SHA1 Message Date
Peter Maydell
7e62609353 docs: Document decodetree named field syntax
Document the named field syntax that we want to implement for the
decodetree script.  This allows a field to be defined in terms of
some other field that the instruction pattern has already set, for
example:

   %sz_imm 10:3 sz:3 !function=expand_sz_imm

to allow a function to be passed both an immediate field from the
instruction and also a sz value which might have been specified by
the instruction pattern directly (sz=1, etc) rather than being a
simple field within the instruction.

Note that the restriction on not having the format referring to the
pattern and the pattern referring to the format simultaneously is a
restriction of the decoder generator rather than inherently being a
silly thing to do.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230523120447.728365-3-peter.maydell@linaro.org>
2023-05-30 10:55:39 -07:00
Richard Henderson
af93ccacc7 decodetree: Extend argument set syntax to allow types
Rather than force all structure members to be 'int',
allow the type of the member to be specified.

Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-05-01 11:45:35 -07:00
Richard Henderson
ffdfca6fac docs/devel: Document decodetree no-overlap groups
When support for this feature went in, the update to the
documentation was forgotten.

Fixes: 067e8b0f45
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20200803205708.315829-1-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-08-04 16:33:47 +01:00
Richard Henderson
94597b6146 decodetree: Allow !function with no input bits
Call this form a "parameter", returning a value extracted
from the DisasContext.

Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-08-19 08:03:41 -07:00
Richard Henderson
0eff2df4a2 decodetree: Allow grouping of overlapping patterns
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-03-12 09:46:58 -07:00
Richard Henderson
5d53b0f5d3 decodetree: Document the usefulness of argument sets
Reviewed-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-03-12 09:46:58 -07:00
Richard Henderson
3fdbf5d679 decodetree: Move documentation to docs/devel/decodetree.rst
One great big block comment isn't the best way to document
the syntax of a language.

Reviewed-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-03-12 09:46:58 -07:00