[turbofan] Inline %_FixedArrayGet intrinsic.

Review URL: https://codereview.chromium.org/1223583003

Cr-Commit-Position: refs/heads/master@{#29438}

src/compiler/js-intrinsic-lowering.cc

@@ -86,6 +86,8 @@ Reduction JSIntrinsicLowering::Reduce(Node* node) {
       return ReduceValueOf(node);
     case Runtime::kInlineIsMinusZero:
       return ReduceIsMinusZero(node);
+    case Runtime::kInlineFixedArrayGet:
+      return ReduceFixedArrayGet(node);
     case Runtime::kInlineFixedArraySet:
       return ReduceFixedArraySet(node);
     case Runtime::kInlineGetTypeFeedbackVector:
@@ -447,6 +449,17 @@ Reduction JSIntrinsicLowering::ReduceIsMinusZero(Node* node) {
 }
 
 
+Reduction JSIntrinsicLowering::ReduceFixedArrayGet(Node* node) {
+  Node* base = node->InputAt(0);
+  Node* index = node->InputAt(1);
+  Node* effect = NodeProperties::GetEffectInput(node);
+  Node* control = NodeProperties::GetControlInput(node);
+  return Change(
+      node, simplified()->LoadElement(AccessBuilder::ForFixedArrayElement()),
+      base, index, effect, control);
+}
+
+
 Reduction JSIntrinsicLowering::ReduceFixedArraySet(Node* node) {
   Node* base = node->InputAt(0);
   Node* index = node->InputAt(1);
@@ -553,6 +566,19 @@ Reduction JSIntrinsicLowering::Change(Node* node, const Operator* op, Node* a,
 }
 
 
+Reduction JSIntrinsicLowering::Change(Node* node, const Operator* op, Node* a,
+                                      Node* b, Node* c, Node* d) {
+  node->set_op(op);
+  node->ReplaceInput(0, a);
+  node->ReplaceInput(1, b);
+  node->ReplaceInput(2, c);
+  node->ReplaceInput(3, d);
+  node->TrimInputCount(4);
+  RelaxControls(node);
+  return Changed(node);
+}
+
+
 Reduction JSIntrinsicLowering::ChangeToUndefined(Node* node, Node* effect) {
   ReplaceWithValue(node, jsgraph()->UndefinedConstant(), effect);
   return Changed(node);

src/compiler/js-intrinsic-lowering.h

@@ -53,6 +53,7 @@ class JSIntrinsicLowering final : public AdvancedReducer {
   Reduction ReduceStringGetLength(Node* node);
   Reduction ReduceUnLikely(Node* node, BranchHint hint);
   Reduction ReduceValueOf(Node* node);
+  Reduction ReduceFixedArrayGet(Node* node);
   Reduction ReduceFixedArraySet(Node* node);
   Reduction ReduceGetTypeFeedbackVector(Node* node);
   Reduction ReduceGetCallerJSFunction(Node* node);
@@ -62,6 +63,8 @@ class JSIntrinsicLowering final : public AdvancedReducer {
   Reduction Change(Node* node, const Operator* op);
   Reduction Change(Node* node, const Operator* op, Node* a, Node* b);
   Reduction Change(Node* node, const Operator* op, Node* a, Node* b, Node* c);
+  Reduction Change(Node* node, const Operator* op, Node* a, Node* b, Node* c,
+                   Node* d);
   Reduction ChangeToUndefined(Node* node, Node* effect = nullptr);
 
   Graph* graph() const;