crucible-wasm: Adapt to new elem format in Wasm 2.0

This bumps the `haskell-wasm` commit to
SPY/haskell-wasm@de40134
and does the minimum amount of work needed to make `crucible-wasm` continue to
compile after these changes. For now, we do not implement full support for Wasm
2.0's new element segment features, as that would require a non-trivial amount
of work to support. See #1228.

crucible-wasm/src/Lang/Crucible/Wasm/Instantiate.hs

@@ -404,12 +404,18 @@ installElemSegment ::
   Wasm.ElemSegment ->
   InstM ()
 installElemSegment im es@Wasm.ElemSegment{ .. } =
-  do I32Val tblOff <- evalConst im offset
+  do (tableIndex, offset) <-
+       case mode of
+         Wasm.Active idx off -> pure (idx, off)
+         Wasm.Passive -> unimplemented "Passive element segments"
+         Wasm.Declarative -> unimplemented "Declarative element segments"
+     I32Val tblOff <- evalConst im offset
+     funcIndexes <- traverse evalConstFuncIndex elements
      st <- lift get
      debug "installing element segment"
      debug (show es)
      debug (show (instTableAddrs im))
-     case updStore (fromIntegral tblOff) st of
+     case updStore tableIndex funcIndexes (fromIntegral tblOff) st of
        Nothing  -> instErr ("failed to evaluate element segment: " <> TL.pack (show es))
        Just st' -> lift (put st')
 
@@ -418,8 +424,8 @@ installElemSegment im [email protected]{ .. } =
     do hdl <- Seq.lookup faddr (storeFuncs st)
        pure (updateFuncTable loc fty hdl ft)
 
-  updStore :: Int -> Store -> Maybe Store
-  updStore off st =
+  updStore :: Wasm.TableIndex -> [Wasm.FuncIndex] -> Int -> Store -> Maybe Store
+  updStore tableIndex funcIndexes off st =
     do (Wasm.TableType (Wasm.Limit lmin _) Wasm.FuncRef, addr) <- resolveTableIndex tableIndex im
        functab <- Seq.lookup addr (storeTables st)
        guard (toInteger off + toInteger (length funcIndexes) <= toInteger lmin)
@@ -463,6 +469,19 @@ evalConst i [Wasm.GetGlobal idx] =
 
 evalConst _ _ = instErr "expression not a constant!"
 
+-- | Evaluate a constant 'Wasm.Expression' that is expected to be a single
+-- 'Wasm.RefFunc' instruction, returning the underlying 'Wasm.FuncIndex'.
+-- Currently, this is only used when computing element segments.
+
+-- TODO: Ideally, we would merge this function with 'evalConst' above by adding
+-- references to functions as a first-class 'ConstantValue'. Doing so would
+-- require fixing https://github.com/GaloisInc/crucible/issues/1228 first,
+-- however.
+evalConstFuncIndex :: Wasm.Expression -> InstM Wasm.FuncIndex
+evalConstFuncIndex [Wasm.RefFunc fi] = pure fi
+evalConstFuncIndex e =
+  instErr $ "expression not a function index constant: " <> fromString (show e)
+
 bindImport :: Namespace -> ModuleInstance -> Wasm.Import -> InstM ExternalValue
 bindImport ns i Wasm.Import{ .. } =
   case namespaceLookup (Wasm.Ident sourceModule) name ns of