Debug API: switch DebugFrameCursor over to monomorphization on T, and provide AsContextMut.
#11873
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…nd provide `AsContextMut`. This permits use of ordinary store accessors, such as GC object accessors, while viewing the stack. In bytecodealliance#11835 and related discussion, we've concluded that (i) it is safe to provide this mutable access, including e.g. ability to do a GC, because debugger access comes only at points that are morally like hostcalls (right now, literally with a `Caller`, and eventually with debug yields); and (ii) we will need this in order to provide the full range of expected debugger functionality. Even before mutation-during-debugging comes into play, with the API before this change, it was not possible to read GC objects at all (because all accessors take a mutable store).
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…nd provide `AsContextMut`. (bytecodealliance#11873) * Debug API: switch `DebugFrameCursor` over to monomorphization on T, and provide `AsContextMut`. This permits use of ordinary store accessors, such as GC object accessors, while viewing the stack. In bytecodealliance#11835 and related discussion, we've concluded that (i) it is safe to provide this mutable access, including e.g. ability to do a GC, because debugger access comes only at points that are morally like hostcalls (right now, literally with a `Caller`, and eventually with debug yields); and (ii) we will need this in order to provide the full range of expected debugger functionality. Even before mutation-during-debugging comes into play, with the API before this change, it was not possible to read GC objects at all (because all accessors take a mutable store). * Review feedback. * Fix some disable-feature builds.
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This permits use of ordinary store accessors, such as GC object accessors, while viewing the stack. In #11835 and related discussion, we've concluded that (i) it is safe to provide this mutable access, including e.g. ability to do a GC, because debugger access comes only at points that are morally like hostcalls (right now, literally with a
Caller, and eventually with debug yields); and (ii) we will need this in order to provide the full range of expected debugger functionality. Even before mutation-during-debugging comes into play, with the API before this change, it was not possible to read GC objects at all (because all accessors take a mutable store).Closes #11835 (this addresses the broader question of access from the debugger, and it seems there wasn't a desire to actually refactor as that issue initially suggested).