Tracking Issue for Coroutine Memory Usage

[jonas-schievink]

(old issue: #52924)

This issue tracks ideas for reducing the memory footprint of coroutines.

• Generator size: borrowed variables are assumed live across following yield points #59087 – Generator size: borrowed variables are assumed live across following yield points
• size_of_val in a generator can make the generator bigger #62321 – size_of_val in a generator can make the generator bigger
• Better greedy layout computation for generators #62575 – Better greedy layout computation for generators
• Copy trait defeats generator optimization #62952 – Copy trait defeats generator optimization
• Async fn doubles argument size #62958 – Async fn doubles argument size
• [codegen] Unnecessary panicking branches in resumption of infinite generator (stored in static variable) #66100 – [codegen] Unnecessary panicking branches in resumption of infinite generator (stored in static variable)
• Generators should use smaller discriminants #69815 – Generators should use smaller discriminants

Note that this issue is different from #69663, which tracks typesystem-level improvements regarding coroutines. This issue is purely about the code generation aspect.

[pnkfelix]

Visiting during T-compiler backlog bonanza. This isn't the same kind of "tracking issue" that we associated with the C-tracking-issue label (in terms of a specific feature being designed)

@rustbot label: +metabug -C-tracking-issue