Hexagon (target/hexagon) Use QEMU decodetree (16-bit instructions)

Section 10.3 of the Hexagon V73 Programmer's Reference Manual

A duplex is encoded as a 32-bit instruction with bits [15:14] set to

Hexagon (target/hexagon) Use QEMU decodetree (16-bit instructions)

Section 10.3 of the Hexagon V73 Programmer's Reference Manual

A duplex is encoded as a 32-bit instruction with bits [15:14] set to 00.
The sub-instructions that comprise a duplex are encoded as 13-bit fields
in the duplex.

Create a decoder for each subinstruction class (a, l1, l2, s1, s2).

Extend gen_trans_funcs.py to handle all instructions rather than
filter by instruction class.

There is a g_assert_not_reached() in decode_insns() in decode.c to
verify we never try to use the old decoder on 16-bit instructions.

Signed-off-by: Taylor Simpson <ltaylorsimpson@gmail.com>
Reviewed-by: Brian Cain <bcain@quicinc.com>
Message-Id: <20240115221443.365287-3-ltaylorsimpson@gmail.com>
Signed-off-by: Brian Cain <bcain@quicinc.com>

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Hexagon (target/hexagon) Use QEMU decodetree (32-bit instructions)

The Decodetree Specification can be found here
https://www.qemu.org/docs/master/devel/decodetree.html

Covers all 32-bit instructio

Hexagon (target/hexagon) Use QEMU decodetree (32-bit instructions)

The Decodetree Specification can be found here
https://www.qemu.org/docs/master/devel/decodetree.html

Covers all 32-bit instructions, including HVX

We generate separate decoders for each instruction class. The reason
will be more apparent in the next patch in this series.

We add 2 new scripts
gen_decodetree.py Generate the input to decodetree.py
gen_trans_funcs.py Generate the trans_* functions used by the
output of decodetree.py

Since the functions generated by decodetree.py take DisasContext * as an
argument, we add the argument to a couple of functions that didn't need
it previously. We also set the insn field in DisasContext during decode
because it is used by the trans_* functions.

There is a g_assert_not_reached() in decode_insns() in decode.c to
verify we never try to use the old decoder on 32-bit instructions

Signed-off-by: Taylor Simpson <ltaylorsimpson@gmail.com>
Reviewed-by: Brian Cain <bcain@quicinc.com>
Message-Id: <20240115221443.365287-2-ltaylorsimpson@gmail.com>
Signed-off-by: Brian Cain <bcain@quicinc.com>

show more ...