[Turbofan] Introduce AllocateRaw node

In order to simplify and verify the TurboFan graph, we
need to wire allocations into the control chain after
effect control linearization.

Bug: v8:7002
Change-Id: I4c5956c8d16773d721482d46a0b407bee01a9597
Reviewed-on: https://chromium-review.googlesource.com/738139Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Michael Stanton <mvstanton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49209}

src/compiler/effect-control-linearizer.cc

@@ -893,6 +893,9 @@ bool EffectControlLinearizer::TryWireInStateEffect(Node* node,
     case IrOpcode::kCheckEqualsInternalizedString:
       LowerCheckEqualsInternalizedString(node, frame_state);
       break;
+    case IrOpcode::kAllocate:
+      result = LowerAllocate(node);
+      break;
     case IrOpcode::kCheckEqualsSymbol:
       LowerCheckEqualsSymbol(node, frame_state);
       break;
@@ -1981,6 +1984,13 @@ Node* EffectControlLinearizer::LowerCheckedTruncateTaggedToWord32(
   return done.PhiAt(0);
 }
 
+Node* EffectControlLinearizer::LowerAllocate(Node* node) {
+  Node* size = node->InputAt(0);
+  PretenureFlag pretenure = PretenureFlagOf(node->op());
+  Node* new_node = __ Allocate(pretenure, size);
+  return new_node;
+}
+
 Node* EffectControlLinearizer::LowerObjectIsArrayBufferView(Node* node) {
   Node* value = node->InputAt(0);
 

src/compiler/effect-control-linearizer.h

@@ -84,6 +84,7 @@ class V8_EXPORT_PRIVATE EffectControlLinearizer {
   Node* LowerTruncateTaggedToFloat64(Node* node);
   Node* LowerTruncateTaggedToWord32(Node* node);
   Node* LowerCheckedTruncateTaggedToWord32(Node* node, Node* frame_state);
+  Node* LowerAllocate(Node* node);
   Node* LowerObjectIsArrayBufferView(Node* node);
   Node* LowerObjectIsCallable(Node* node);
   Node* LowerObjectIsConstructor(Node* node);

src/compiler/graph-assembler.cc

@@ -97,8 +97,8 @@ Node* GraphAssembler::Projection(int index, Node* value) {
 }
 
 Node* GraphAssembler::Allocate(PretenureFlag pretenure, Node* size) {
-  return current_effect_ =
-             graph()->NewNode(simplified()->Allocate(Type::Any(), NOT_TENURED),
+  return current_control_ = current_effect_ =
+             graph()->NewNode(simplified()->AllocateRaw(Type::Any(), pretenure),
                               size, current_effect_, current_control_);
 }
 

src/compiler/memory-optimizer.cc

@@ -75,7 +75,11 @@ void MemoryOptimizer::VisitNode(Node* node, AllocationState const* state) {
   DCHECK_LT(0, node->op()->EffectInputCount());
   switch (node->opcode()) {
     case IrOpcode::kAllocate:
-      return VisitAllocate(node, state);
+      // Allocate nodes were purged from the graph in effect-control
+      // linearization.
+      UNREACHABLE();
+    case IrOpcode::kAllocateRaw:
+      return VisitAllocateRaw(node, state);
     case IrOpcode::kCall:
       return VisitCall(node, state);
     case IrOpcode::kCallWithCallerSavedRegisters:
@@ -110,8 +114,9 @@ void MemoryOptimizer::VisitNode(Node* node, AllocationState const* state) {
 
 #define __ gasm()->
 
-void MemoryOptimizer::VisitAllocate(Node* node, AllocationState const* state) {
-  DCHECK_EQ(IrOpcode::kAllocate, node->opcode());
+void MemoryOptimizer::VisitAllocateRaw(Node* node,
+                                       AllocationState const* state) {
+  DCHECK_EQ(IrOpcode::kAllocateRaw, node->opcode());
   Node* value;
   Node* size = node->InputAt(0);
   Node* effect = node->InputAt(1);
@@ -130,7 +135,7 @@ void MemoryOptimizer::VisitAllocate(Node* node, AllocationState const* state) {
       Node* const user = edge.from();
       if (user->opcode() == IrOpcode::kStoreField && edge.index() == 0) {
         Node* const child = user->InputAt(1);
-        if (child->opcode() == IrOpcode::kAllocate &&
+        if (child->opcode() == IrOpcode::kAllocateRaw &&
             PretenureFlagOf(child->op()) == NOT_TENURED) {
           NodeProperties::ChangeOp(child, node->op());
           break;
@@ -143,7 +148,7 @@ void MemoryOptimizer::VisitAllocate(Node* node, AllocationState const* state) {
       Node* const user = edge.from();
       if (user->opcode() == IrOpcode::kStoreField && edge.index() == 1) {
         Node* const parent = user->InputAt(0);
-        if (parent->opcode() == IrOpcode::kAllocate &&
+        if (parent->opcode() == IrOpcode::kAllocateRaw &&
             PretenureFlagOf(parent->op()) == TENURED) {
           pretenure = TENURED;
           break;
@@ -298,7 +303,6 @@ void MemoryOptimizer::VisitAllocate(Node* node, AllocationState const* state) {
 
   effect = __ ExtractCurrentEffect();
   control = __ ExtractCurrentControl();
-  USE(control);  // Floating control, dropped on the floor.
 
   // Replace all effect uses of {node} with the {effect}, enqueue the
   // effect uses for further processing, and replace all value uses of
@@ -307,9 +311,11 @@ void MemoryOptimizer::VisitAllocate(Node* node, AllocationState const* state) {
     if (NodeProperties::IsEffectEdge(edge)) {
       EnqueueUse(edge.from(), edge.index(), state);
       edge.UpdateTo(effect);
-    } else {
-      DCHECK(NodeProperties::IsValueEdge(edge));
+    } else if (NodeProperties::IsValueEdge(edge)) {
       edge.UpdateTo(value);
+    } else {
+      DCHECK(NodeProperties::IsControlEdge(edge));
+      edge.UpdateTo(control);
     }
   }
 

src/compiler/memory-optimizer.h

@@ -106,7 +106,7 @@ class MemoryOptimizer final {
   };
 
   void VisitNode(Node*, AllocationState const*);
-  void VisitAllocate(Node*, AllocationState const*);
+  void VisitAllocateRaw(Node*, AllocationState const*);
   void VisitCall(Node*, AllocationState const*);
   void VisitCallWithCallerSavedRegisters(Node*, AllocationState const*);
   void VisitLoadElement(Node*, AllocationState const*);

src/compiler/opcodes.h

@@ -346,6 +346,7 @@
   V(TypeOf)                             \
   V(ClassOf)                            \
   V(Allocate)                           \
+  V(AllocateRaw)                        \
   V(LoadFieldByIndex)                   \
   V(LoadField)                          \
   V(LoadElement)                        \

src/compiler/simplified-operator.cc

@@ -510,7 +510,8 @@ PretenureFlag PretenureFlagOf(const Operator* op) {
       op->opcode() == IrOpcode::kNewSmiOrObjectElements) {
     return OpParameter<PretenureFlag>(op);
   }
-  DCHECK_EQ(IrOpcode::kAllocate, op->opcode());
+  DCHECK(op->opcode() == IrOpcode::kAllocate ||
+         op->opcode() == IrOpcode::kAllocateRaw);
   return OpParameter<AllocateParameters>(op).pretenure();
 }
 
@@ -1208,6 +1209,14 @@ const Operator* SimplifiedOperatorBuilder::Allocate(Type* type,
       1, 1, 1, 1, 1, 0, AllocateParameters(type, pretenure));
 }
 
+const Operator* SimplifiedOperatorBuilder::AllocateRaw(
+    Type* type, PretenureFlag pretenure) {
+  return new (zone()) Operator1<AllocateParameters>(
+      IrOpcode::kAllocateRaw,
+      Operator::kNoDeopt | Operator::kNoThrow | Operator::kNoWrite,
+      "AllocateRaw", 1, 1, 1, 1, 1, 1, AllocateParameters(type, pretenure));
+}
+
 const Operator* SimplifiedOperatorBuilder::StringFromCodePoint(
     UnicodeEncoding encoding) {
   switch (encoding) {

src/compiler/simplified-operator.h

@@ -517,6 +517,8 @@ class V8_EXPORT_PRIVATE SimplifiedOperatorBuilder final
   const Operator* TransitionElementsKind(ElementsTransition transition);
 
   const Operator* Allocate(Type* type, PretenureFlag pretenure = NOT_TENURED);
+  const Operator* AllocateRaw(Type* type,
+                              PretenureFlag pretenure = NOT_TENURED);
 
   const Operator* LoadFieldByIndex();
   const Operator* LoadField(FieldAccess const&);

src/compiler/typer.cc

@@ -1941,6 +1941,8 @@ Type* Typer::Visitor::TypeAllocate(Node* node) {
   return AllocateTypeOf(node->op());
 }
 
+Type* Typer::Visitor::TypeAllocateRaw(Node* node) { UNREACHABLE(); }
+
 Type* Typer::Visitor::TypeLoadFieldByIndex(Node* node) {
   return Type::NonInternal();
 }

src/compiler/verifier.cc

@@ -1090,6 +1090,9 @@ void Verifier::Visitor::Check(Node* node) {
     case IrOpcode::kAllocate:
       CheckValueInputIs(node, 0, Type::PlainNumber());
       break;
+    case IrOpcode::kAllocateRaw:
+      // CheckValueInputIs(node, 0, Type::PlainNumber());
+      break;
     case IrOpcode::kEnsureWritableFastElements:
       CheckValueInputIs(node, 0, Type::Any());
       CheckValueInputIs(node, 1, Type::Internal());