[turbofan] Exhaustive switches for MachineRepresentation.

src/compiler/arm64/instruction-selector-arm64.cc

Index: src/compiler/arm64/instruction-selector-arm64.cc
diff --git a/src/compiler/arm64/instruction-selector-arm64.cc b/src/compiler/arm64/instruction-selector-arm64.cc
index ee2554dd10b3c1e3188990c11929f1558b8aff05..ca6569c7aa9f778e1a8a0fc6bc3adc624af2396b 100644
--- a/src/compiler/arm64/instruction-selector-arm64.cc
+++ b/src/compiler/arm64/instruction-selector-arm64.cc
@@ -342,7 +342,7 @@ void InstructionSelector::VisitLoad(Node* node) {
   Arm64OperandGenerator g(this);
   Node* base = node->InputAt(0);
   Node* index = node->InputAt(1);
-  ArchOpcode opcode;
+  ArchOpcode opcode = kArchNop;
   ImmediateMode immediate_mode = kNoImmediate;
   switch (load_rep.representation()) {
     case MachineRepresentation::kFloat32:
@@ -371,7 +371,7 @@ void InstructionSelector::VisitLoad(Node* node) {
       opcode = kArm64Ldr;
       immediate_mode = kLoadStoreImm64;
       break;
-    default:
+    case MachineRepresentation::kNone:
       UNREACHABLE();
       return;
   }
@@ -426,7 +426,7 @@ void InstructionSelector::VisitStore(Node* node) {
     code |= MiscField::encode(static_cast<int>(record_write_mode));
     Emit(code, 0, nullptr, input_count, inputs, temp_count, temps);
   } else {
-    ArchOpcode opcode;
+    ArchOpcode opcode = kArchNop;
     ImmediateMode immediate_mode = kNoImmediate;
     switch (rep) {
       case MachineRepresentation::kFloat32:
@@ -455,7 +455,7 @@ void InstructionSelector::VisitStore(Node* node) {
         opcode = kArm64Str;
         immediate_mode = kLoadStoreImm64;
         break;
-      default:
+      case MachineRepresentation::kNone:
         UNREACHABLE();
         return;
     }
@@ -476,7 +476,7 @@ void InstructionSelector::VisitCheckedLoad(Node* node) {
   Node* const buffer = node->InputAt(0);
   Node* const offset = node->InputAt(1);
   Node* const length = node->InputAt(2);
-  ArchOpcode opcode;
+  ArchOpcode opcode = kArchNop;
   switch (load_rep.representation()) {
     case MachineRepresentation::kWord8:
       opcode = load_rep.IsSigned() ? kCheckedLoadInt8 : kCheckedLoadUint8;
@@ -496,7 +496,9 @@ void InstructionSelector::VisitCheckedLoad(Node* node) {
     case MachineRepresentation::kFloat64:
       opcode = kCheckedLoadFloat64;
       break;
-    default:
+    case MachineRepresentation::kBit:     // Fall through.
+    case MachineRepresentation::kTagged:  // Fall through.
+    case MachineRepresentation::kNone:
       UNREACHABLE();
       return;
   }
@@ -512,7 +514,7 @@ void InstructionSelector::VisitCheckedStore(Node* node) {
   Node* const offset = node->InputAt(1);
   Node* const length = node->InputAt(2);
   Node* const value = node->InputAt(3);
-  ArchOpcode opcode;
+  ArchOpcode opcode = kArchNop;
   switch (rep) {
     case MachineRepresentation::kWord8:
       opcode = kCheckedStoreWord8;
@@ -532,7 +534,9 @@ void InstructionSelector::VisitCheckedStore(Node* node) {
     case MachineRepresentation::kFloat64:
       opcode = kCheckedStoreFloat64;
       break;
-    default:
+    case MachineRepresentation::kBit:     // Fall through.
+    case MachineRepresentation::kTagged:  // Fall through.
+    case MachineRepresentation::kNone:
       UNREACHABLE();
       return;
   }