target/arm: Make Thumb store insns UNDEF for Rn==1111
commit8196fe9d83d6519128b514f332418bae06513970
authorPeter Maydell <peter.maydell@linaro.org>
Thu, 8 Apr 2021 16:24:02 +0000 (8 17:24 +0100)
committerPeter Maydell <peter.maydell@linaro.org>
Fri, 30 Apr 2021 10:16:49 +0000 (30 11:16 +0100)
treeef7ba90be1eaed8a1a8aab69e6edde42bd0bb8be
parentbf559ee4025adaf9713e22def862d31f1db5994e
target/arm: Make Thumb store insns UNDEF for Rn==1111

The Arm ARM specifies that for Thumb encodings of the various plain
store insns, if the Rn field is 1111 then we must UNDEF.  This is
different from the Arm encodings, where this case is either
UNPREDICTABLE or has well-defined behaviour.  The exclusive stores,
store-release and STRD do not have this UNDEF case for any encoding.

Enforce the UNDEF for this case in the Thumb plain store insns.

Fixes: https://bugs.launchpad.net/qemu/+bug/1922887
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210408162402.5822-1-peter.maydell@linaro.org
target/arm/translate.c