| Commit message (Collapse) | Author | Files | Lines |
|---|
|
Add some tests for various cases of named-field use, both ones that
should work and ones that should be diagnosed as errors.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230523120447.728365-7-peter.maydell@linaro.org>
|
|
Implement support for named fields, i.e. where one field is defined
in terms of another, rather than directly in terms of bits extracted
from the instruction.
The new method referenced_fields() on all the Field classes returns a
list of fields that this field references. This just passes through,
except for the new NamedField class.
We can then use referenced_fields() to:
* construct a list of 'dangling references' for a format or
pattern, which is the fields that the format/pattern uses but
doesn't define itself
* do a topological sort, so that we output "field = value"
assignments in an order that means that we assign a field before
we reference it in a subsequent assignment
* check when we output the code for a pattern whether we need to
fill in the format fields before or after the pattern fields, and
do other error checking
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230523120447.728365-6-peter.maydell@linaro.org>
|
|
To support named fields, we will need to be able to do a topological
sort (so that we ensure that we output the assignment to field A
before the assignment to field B if field B refers to field A by
name). The good news is that there is a tsort in the python standard
library; the bad news is that it was only added in Python 3.9.
To bridge the gap between our current minimum supported Python
version and 3.9, provide a local implementation that has the
same API as the stdlib version for the parts we care about.
In future when QEMU's minimum Python version requirement reaches
3.9 we can delete this code and replace it with an 'import' line.
The core of this implementation is based on
https://code.activestate.com/recipes/578272-topological-sort/
which is MIT-licensed.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230523120447.728365-5-peter.maydell@linaro.org>
|
|
To support referring to other named fields in field definitions, we
need to pass the str_extract() method a function which tells it how
to emit the code for a previously initialized named field. (In
Pattern::output_code() the other field will be "u.f_foo.field", and
in Format::output_extract() it is "a->field".)
Refactor the two callsites that currently do "output code to
initialize each field", and have them pass a lambda that defines how
to format the lvalue in each case. This is then used both in
emitting the LHS of the assignment and also passed down to
str_extract() as a new argument (unused at the moment, but will be
used in the following patch).
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230523120447.728365-4-peter.maydell@linaro.org>
|
|
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>
|
|
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
|
|
Nor report any PermissionError on remove.
The primary purpose is testing with -o /dev/null.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
|
|
Test err_pattern_group_empty.decode failed with exception:
Traceback (most recent call last):
File "./scripts/decodetree.py", line 1424, in <module> main()
File "./scripts/decodetree.py", line 1342, in main toppat.build_tree()
File "./scripts/decodetree.py", line 627, in build_tree
self.tree = self.__build_tree(self.pats, self.fixedbits,
File "./scripts/decodetree.py", line 607, in __build_tree
fb = i.fi |