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Debugging: edit breakpoints and watchpoints through BreakpointState. - #15185
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In order to prepare for record/replay and reversible debugging, we need a little more discipline about read-only vs. read-write access to the `Store`. The breakpoint/watchpoint state in the store is a logically separate thing that has more to do with execution strategy than the actual Wasm state (i.e., cannot affect Wasm state). Also, separately, breakpoints and watchpoints have a somewhat distributed API surface: breakpoints are edited via the existing `Store::edit_breakpoints` that returns a `BreakpointEdit` view struct, while watchpoints are edited via `Memory::debug_watch`. Watchpoints are really a kind of breakpoint (if you squint enough) and both should be managed in the same way. This PR introduces a `BreakpointState` view struct in the API returned from `Store::edit_breakpoints` that manages both breakpoints and watchpoints. This solves both problems: we can now treat `BreakpointState` as a thing that we can hand out mutably in future record/replay debug APIs (when the overall store is read-only), providing access to exactly and only the bit of execution-control state we want to be mutable.
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Nov 6, 2026
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In order to prepare for record/replay and reversible debugging, we need a little more discipline about read-only vs. read-write access to the
Store. The breakpoint/watchpoint state in the store is a logically separate thing that has more to do with execution strategy than the actual Wasm state (i.e., cannot affect Wasm state).Also, separately, breakpoints and watchpoints have a somewhat distributed API surface: breakpoints are edited via the existing
Store::edit_breakpointsthat returns aBreakpointEditview struct, while watchpoints are edited viaMemory::debug_watch. Watchpoints are really a kind of breakpoint (if you squint enough) and both should be managed in the same way.This PR introduces a
BreakpointStateview struct in the API returned fromStore::edit_breakpointsthat manages both breakpoints and watchpoints. This solves both problems: we can now treatBreakpointStateas a thing that we can hand out mutably in future record/replay debug APIs (when the overall store is read-only), providing access to exactly and only the bit of execution-control state we want to be mutable.