Implement UnalignedLoad and UnalignedStore in WASM using LoadByte/Shift/Or and StoreByte/Shift/And.

src/compiler/wasm-compiler.h

Index: src/compiler/wasm-compiler.h
diff --git a/src/compiler/wasm-compiler.h b/src/compiler/wasm-compiler.h
index ee7f521c9fc23d42b79a4a4f359d1e6e44a147b6..f9b490875758db5882043e709fd9d38be18d6e13 100644
--- a/src/compiler/wasm-compiler.h
+++ b/src/compiler/wasm-compiler.h
@@ -141,8 +141,10 @@ class WasmGraphBuilder {
   Node* LoadGlobal(uint32_t index);
   Node* StoreGlobal(uint32_t index, Node* val);
   Node* LoadMem(wasm::LocalType type, MachineType memtype, Node* index,
-                uint32_t offset, wasm::WasmCodePosition position);
-  Node* StoreMem(MachineType type, Node* index, uint32_t offset, Node* val,
+                uint32_t offset, uint32_t alignment,
+                wasm::WasmCodePosition position);
+  Node* StoreMem(MachineType type, Node* index, uint32_t offset,
+                 uint32_t alignment, Node* val,
                  wasm::WasmCodePosition position);
 
   static void PrintDebugName(Node* node);
@@ -193,6 +195,14 @@ class WasmGraphBuilder {
   void BoundsCheckMem(MachineType memtype, Node* index, uint32_t offset,
                       wasm::WasmCodePosition position);
 
+  MachineType GetTypeForUnalignedAccess(uint32_t alignment,
+                                        bool signExtend = false);
+
+  Node* BuildUnalignedLoad(wasm::LocalType type, MachineType memtype,
+                           Node* index, uint32_t offset, uint32_t alignment);
+  Node* BuildUnalignedStore(MachineType memtype, Node* index, uint32_t offset,
+                            uint32_t alignment, Node* val);
+
   Node* MaskShiftCount32(Node* node);
   Node* MaskShiftCount64(Node* node);