In commit 8f0a4b6a9b, we started to require L=0 for ppc32 to match what
The Programming Environments Manual say:
"For 32-bit implementations, the L field must be cleared, otherwise
the instruction form is invalid."
The stricter behavior, however, broke AROS boot on sam460ex, which is a
regression from 6.0. This patch partially reverts the change, raising
the exception only for CPUs known to require L=0 (e500 and e500mc) and
logging a guest error for other cases.
Both behaviors are acceptable by the PowerISA, which allows "the system
illegal instruction error handler to be invoked or yield boundedly
undefined results."
Reported-by: BALATON Zoltan <balaton@eik.bme.hu>
Fixes: 8f0a4b6a9b ("target/ppc: Move cmp/cmpi/cmpl/cmpli to decodetree")
Tested-by: BALATON Zoltan <balaton@eik.bme.hu>
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Message-Id: <20210720135507.2444635-1-matheus.ferst@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Additionally, REQUIRE_64BIT when L=1 to match what is specified in The
Programming Environments Manual:
"For 32-bit implementations, the L field must be cleared, otherwise the
instruction form is invalid."
Some CPUs are known to deviate from this specification by ignoring the
L bit [1]. The stricter behavior, however, can help users that test
software with qemu, making it more likely to detect bugs that would
otherwise be silent.
If deemed necessary, a future patch can adapt this behavior based on
the specific CPU model.
[1] The 601 manual is the only one I've found that explicitly states
that the L bit is ignored, but we also observe this behavior in a 7447A
v1.2.
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Message-Id: <20210601193528.2533031-15-matheus.ferst@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
[dwg: Corrected whitespace error]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
These are all connected by macros in the legacy decoding.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Message-Id: <20210601193528.2533031-9-matheus.ferst@eldorado.org.br>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
These are all connected by macros in the legacy decoding.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Message-Id: <20210601193528.2533031-7-matheus.ferst@eldorado.org.br>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The illegal suffix behavior matches what was observed in a
POWER10 DD2.0 machine.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Message-Id: <20210601193528.2533031-6-matheus.ferst@eldorado.org.br>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>