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| H A D | ops_sse.h | diff bf30ad8cefeb3b199f5485c5d78f2801cd248264 Thu Aug 25 11:47:50 CDT 2022 Paolo Bonzini <pbonzini@redhat.com> target/i386: DPPS rounding fix
The DPPS (Dot Product) instruction is defined to first sum pairs of
intermediate results, then sum those values to get the final result.
i.e. (A+B)+(C+D)
We incrementally sum the results, i.e. ((A+B)+C)+D, which can result
in incorrect rouding.
For consistency, also change the variable names to the ones used
in the Intel SDM and implement DPPD following the manual.
Based on a patch by Paul Brook <paul@nowt.org>.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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