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| author | Philippe Mathieu-Daudé <philmd@linaro.org> | 2024-04-30 13:10:19 +0200 |
|---|---|---|
| committer | Philippe Mathieu-Daudé <philmd@linaro.org> | 2024-05-03 17:33:26 +0200 |
| commit | e88a856efd1d3c3ffa8e53da4831eff8da290808 (patch) | |
| tree | fbede5a15ad64f42d37671df096e282168e7ea34 /host | |
| parent | c365e6b0705788866a65e7b8206bd4c5332595cd (diff) | |
| download | qemu-e88a856efd1d3c3ffa8e53da4831eff8da290808.zip qemu-e88a856efd1d3c3ffa8e53da4831eff8da290808.tar.gz qemu-e88a856efd1d3c3ffa8e53da4831eff8da290808.tar.bz2 | |
target/sh4: Fix SUBV opcode
The documentation says:
SUBV Rm, Rn Rn - Rm -> Rn, underflow -> T
The overflow / underflow can be calculated as:
T = ((Rn ^ Rm) & (Result ^ Rn)) >> 31
However we were using the incorrect:
T = ((Rn ^ Rm) & (Result ^ Rm)) >> 31
Fix by using the Rn register instead of Rm.
Add tests provided by Paul Cercueil.
Cc: qemu-stable@nongnu.org
Fixes: ad8d25a11f ("target-sh4: implement addv and subv using TCG")
Reported-by: Paul Cercueil <paul@crapouillou.net>
Suggested-by: Paul Cercueil <paul@crapouillou.net>
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2318
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Message-Id: <20240430163125.77430-3-philmd@linaro.org>
Diffstat (limited to 'host')
0 files changed, 0 insertions, 0 deletions