Before falling back to softfloat FMA, we do not restore the original
values of inputs A and C. Fix it.
This bug was caught by running gcc's testsuite on RISC-V qemu.
Note that this change gives a small perf increase for fp-bench:
Host: Intel(R) Core(TM) i7-4790K CPU @ 4.00GHz
Command: perf stat -r 3 taskset -c 0 ./fp-bench -o mulAdd -p $prec
- $prec = single:
- before:
101.71 MFlops
102.18 MFlops
100.96 MFlops
- after:
103.63 MFlops
103.05 MFlops
102.96 MFlops
- $prec = double:
- before:
173.10 MFlops
173.93 MFlops
172.11 MFlops
- after:
178.49 MFlops
178.88 MFlops
178.66 MFlops
Signed-off-by: Kito Cheng <kito.cheng@gmail.com>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <20190322204320.17777-1-cota@braap.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
896f51fbfa