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| 1 | namespace IR.Values is | |
| 2 | use TypeTyped = Semantic.Types.Typed; | |
| 3 | use Semantic.Types.Type; | |
| 4 | ||
| 5 | // Wraps the creation of a stateless delegate (a zero-capture, | |
| 6 | // ground function literal) so it is built at most once and reused. | |
| 7 | // The first evaluation allocates the delegate and stores it into a | |
| 8 | // static cache field; every later evaluation loads the cached one. | |
| 9 | // Behaviour matches `inner` exactly because the wrapped literal | |
| 10 | // captures nothing and carries no type arguments, so a single | |
| 11 | // instance is interchangeable everywhere it is used. | |
| 12 | // | |
| 13 | // ldsfld <cache> | |
| 14 | // dup | |
| 15 | // brtrue Lpresent | |
| 16 | // pop | |
| 17 | // <inner delegate-creation IL> | |
| 18 | // dup | |
| 19 | // stsfld <cache> | |
| 20 | // Lpresent: | |
| 21 | class MEMOIZED_DELEGATE: Value, TypeTyped is | |
| 22 | _inner: Value; | |
| 23 | _cache_reference: string; | |
| 24 | _type: Type; | |
| 25 | ||
| 26 | type: Type => _type; | |
| 27 | ||
| 28 | init(inner: Value, cache_reference: string, type: Type) is | |
| 29 | super.init(); | |
| 30 | ||
| 31 | _inner = inner; | |
| 32 | _cache_reference = cache_reference; | |
| 33 | _type = type; | |
| 34 | si | |
| 35 | ||
| 36 | referenced_function: Semantic.Symbols.Function? => _inner.referenced_function; | |
| 37 | ||
| 38 | // Stay live rather than freezing to a pre-rendered RAW: gen() | |
| 39 | // mints a fresh cache-hoist label per emit site, so a delegate | |
| 40 | // referenced from more than one place (notably a guarded | |
| 41 | // pipe-fusion's fused path AND its fallback, which both emit the | |
| 42 | // stage delegate) gets distinct labels instead of one baked into | |
| 43 | // a RAW and duplicated. | |
| 44 | freeze() -> Value => self; | |
| 45 | ||
| 46 | gen(context: IR.CONTEXT) is | |
| 47 | let present = IR.LABEL(); | |
| 48 | ||
| 49 | context.write_line("ldsfld {_cache_reference}"); | |
| 50 | context.write_line("dup"); | |
| 51 | context.write_line("brtrue {present}"); | |
| 52 | context.write_line("pop"); | |
| 53 | gen(_inner, context); | |
| 54 | context.write_line("dup"); | |
| 55 | context.write_line("stsfld {_cache_reference}"); | |
| 56 | context.write_line("{present}:"); | |
| 57 | si | |
| 58 | ||
| 59 | to_string() -> string => | |
| 60 | "memoized-delegate:[{_type}]({_inner})"; | |
| 61 | si | |
| 62 | si |