21 lines
938 B
TeX
21 lines
938 B
TeX
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\section{Resource models}
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As we saw earlier in \qtodo{ref}, the behaviour of a CPU's backend can be,
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throughput-wise, characterized by the behaviour of its ports. Thus, a
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throughput model of the backend consists in a mapping of the ISA's instructions
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to execution ports of the backend, called a \emph{port mapping}.
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The mapping, however, is not direct: we also saw in \qtodo{ref} that
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instructions are themselves broken down into a number of \uops{}, which all
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have to be executed. Each of those \uops{} are then scheduled on one of the
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compatible execution ports of the CPU. A port mapping, thus, is actually a
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tripartite graph: a first layer mapping instructions to \uops{}, followed by a
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second layer mapping \uops{} to ports. In
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\autoref{fig:port_mapping_excerpt_skx_tri},
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\begin{figure}
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\centering
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%\includegraphics{../assets/imgs/30_palmed/p0156_tri}
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\includegraphics[width=0.2\textwidth]{hedgehog.jpg}
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\end{figure}
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