JIT: Add a simple store-forwarding optimization for structs returned in registers #86388
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…in registers In cases where we see a primitive store into a struct that is then returned in a register we can often optimize to just return the source of the store directly. This is especially important for physical promotion that creates this pattern a lot.
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Tagging subscribers to this area: @JulieLeeMSFT, @jakobbotsch Issue DetailsIn cases where we see a primitive store into a struct that is then returned in a register we can often optimize to just return the source of the store directly. This is especially important for physical promotion that creates this pattern a lot.
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There's not much reason to take this change when the structs that are actually returned in registers are typically promoted via old promotion anyway (where it is already supported through some retyping shenanigans). It's very visible from the diffs:
This is the kind of change we need to take if we want to invest in replacing old promotion with physical promotion entirely, but we're not quite there yet, so am going to close this. |
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In cases where we see a primitive store into a struct that is then returned in a register we can often optimize to just return the source of the store directly. This is especially important for physical promotion that creates this pattern a lot.