libexpr: remove Displacement field from ExprAttrs::AttrDef #14160
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Waste of 4 bytes; it can be calculated where it's needed. I also reordered the remaining fields to avoid padding
xokdvium
reviewed
Oct 5, 2025
| Hence we need __overrides.) */ | ||
| if (hasOverrides) { | ||
| Value * vOverrides = (*bindings.bindings)[overrides->second.displ].value; | ||
| Value * vOverrides = (*bindings.bindings)[std::distance(attrs.begin(), overrides)].value; |
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Accidental complexity jump here. Also can we add a bit more tests for __overrides feature?
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Isn't |
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You're both right. I didn't realize that's how |
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Motivation
Waste of 4 bytes (per attr definition, and there are a lot of attr definitions). It's just the offset into the
std::map, and can be calculated where it's needed usingstd::distance().I also reordered the remaining fields to avoid padding
Saves ~1% memory (~10MB)
Additional benefits:
AttrDefs to be mutable after parsing, which is useful for reworkingExprAttrsContext
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CC @xokdvium @NaN-git