Fix another case of Miri unsoundness #11056
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This commit fixes another issue we've discovered in the wasip3 prototyping repository about a code pattern in wasm which Miri flags as un-sound. Specifically what happened was: * Invocation of WebAssembly went through `VMFuncRef::array_call` which takes a `&self` parameter. * Inside of WebAssembly though a `ref.func` instruction, or anything else that references the original exported function, will re-initialize the `VMFuncRef` which writes the `&self` up the stack, which is not sound. Fixing this required changing the signature of `array_call` from `&self` to `me: NonNull<VMFuncRef>`, and the signature was already `unsafe` so this is a new unsafe contract for that signature. In fixing this, however, it was discovered that a mistake was made in bytecodealliance#10943 where some internal functions for re-initializing a `VMFuncRef` relied on the previous signature of `&mut self` but that PR switche to `&self`. This PR corrects these signatures to `Pin<&mut Self>` and then plumbs around the necessary changes, notably causing some refactoring in component-related bits.
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This commit fixes another issue we've discovered in the wasip3 prototyping repository about a code pattern in wasm which Miri flags as un-sound. Specifically what happened was:
Invocation of WebAssembly went through
VMFuncRef::array_callwhich takes a&selfparameter.Inside of WebAssembly though a
ref.funcinstruction, or anything else that references the original exported function, will re-initialize theVMFuncRefwhich writes the&selfup the stack, which is not sound.Fixing this required changing the signature of
array_callfrom&selftome: NonNull<VMFuncRef>, and the signature was alreadyunsafeso this is a new unsafe contract for that signature.In fixing this, however, it was discovered that a mistake was made in #10943 where some internal functions for re-initializing a
VMFuncRefrelied on the previous signature of&mut selfbut that PR switche to&self. This PR corrects these signatures toPin<&mut Self>and then plumbs around the necessary changes, notably causing some refactoring in component-related bits.