34 lines
903 B
Markdown
34 lines
903 B
Markdown
# Code Generation
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## Data Representation
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Every type has a "handle". If a type is a simple primitive type such as i32 or
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f64, the handle is "by value", meaning that we pass around the value itself when
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we refer to a value of that type.
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If a type is a container, error union, maybe type, slice, or array, then its
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handle is a pointer, and everywhere we refer to a value of this type we refer to
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a pointer.
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Parameters and return values are always passed as handles.
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Error union types are represented as:
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struct {
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error: u32,
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payload: T,
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}
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Maybe types are represented as:
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struct {
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payload: T,
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is_non_null: u1,
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}
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## Data Optimizations
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Maybe pointer types are special: the 0x0 pointer value is used to represent a
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null pointer. Thus, instead of the struct above, maybe pointer types are
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represented as a `usize` in codegen and the handle is by value.
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