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

src/compiler/instruction-selector.h

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_COMPILER_INSTRUCTION_SELECTOR_H_
 #define V8_COMPILER_INSTRUCTION_SELECTOR_H_
 
 #include <map>
 
 #include "src/compiler/common-operator.h"
@@ skipping 121 matching lines @@
   }
 
   // Returns the features supported on the target platform.
   static Features SupportedFeatures() {
     return Features(CpuFeatures::SupportedFeatures());
   }
 
   // TODO(sigurds) This should take a CpuFeatures argument.
   static MachineOperatorBuilder::Flags SupportedMachineOperatorFlags();
 
+  static MachineOperatorBuilder::AlignmentRequirements AlignmentRequirements();
+
   // ===========================================================================
   // ============ Architecture-independent graph covering methods. =============
   // ===========================================================================
 
   // Used in pattern matching during code generation.
   // Check if {node} can be covered while generating code for the current
   // instruction. A node can be covered if the {user} of the node has the only
   // edge and the two are in the same basic block.
   bool CanCover(Node* user, Node* node) const;
 
@@ skipping 141 matching lines @@
   IntVector virtual_registers_;
   InstructionScheduler* scheduler_;
   Frame* frame_;
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_INSTRUCTION_SELECTOR_H_