[compiler] Introduce code stubs for string relational comparisons.

src/compiler/simplified-lowering.cc

 // 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.
 
 #include "src/compiler/simplified-lowering.h"
 
 #include <limits>
 
 #include "src/base/bits.h"
 #include "src/code-factory.h"
@@ skipping 1142 matching lines @@
               jsgraph_->isolate(), jsgraph_->zone(), callable.descriptor(), 0,
               flags, properties);
           node->InsertInput(jsgraph_->zone(), 0,
                             jsgraph_->HeapConstant(callable.code()));
           node->InsertInput(jsgraph_->zone(), 3, jsgraph_->NoContextConstant());
           NodeProperties::ChangeOp(node, jsgraph_->common()->Call(desc));
         }
         break;
       }
       case IrOpcode::kStringLessThan: {
-        VisitBinop(node, UseInfo::AnyTagged(), NodeOutputInfo::Bool());
-        if (lower()) lowering->DoStringLessThan(node);
+        VisitBinop(node, UseInfo::AnyTagged(), NodeOutputInfo::BoolTagged());
+        if (lower()) {
+          // StringLessThan(x, y) => Call(StringLessThanStub, x, y, no-context)
+          Operator::Properties properties = node->op()->properties();
+          Callable callable = CodeFactory::StringLessThan(jsgraph_->isolate());
+          CallDescriptor::Flags flags = CallDescriptor::kNoFlags;
+          CallDescriptor* desc = Linkage::GetStubCallDescriptor(
+              jsgraph_->isolate(), jsgraph_->zone(), callable.descriptor(), 0,
+              flags, properties);
+          node->InsertInput(jsgraph_->zone(), 0,
+                            jsgraph_->HeapConstant(callable.code()));
+          node->InsertInput(jsgraph_->zone(), 3, jsgraph_->NoContextConstant());
+          NodeProperties::ChangeOp(node, jsgraph_->common()->Call(desc));
+        }
         break;
       }
       case IrOpcode::kStringLessThanOrEqual: {
-        VisitBinop(node, UseInfo::AnyTagged(), NodeOutputInfo::Bool());
-        if (lower()) lowering->DoStringLessThanOrEqual(node);
+        VisitBinop(node, UseInfo::AnyTagged(), NodeOutputInfo::BoolTagged());
+        if (lower()) {
+          // StringLessThanOrEqual(x, y)
+          //   => Call(StringLessThanOrEqualStub, x, y, no-context)
+          Operator::Properties properties = node->op()->properties();
+          Callable callable =
+              CodeFactory::StringLessThanOrEqual(jsgraph_->isolate());
+          CallDescriptor::Flags flags = CallDescriptor::kNoFlags;
+          CallDescriptor* desc = Linkage::GetStubCallDescriptor(
+              jsgraph_->isolate(), jsgraph_->zone(), callable.descriptor(), 0,
+              flags, properties);
+          node->InsertInput(jsgraph_->zone(), 0,
+                            jsgraph_->HeapConstant(callable.code()));
+          node->InsertInput(jsgraph_->zone(), 3, jsgraph_->NoContextConstant());
+          NodeProperties::ChangeOp(node, jsgraph_->common()->Call(desc));
+        }
         break;
       }
       case IrOpcode::kAllocate: {
         ProcessInput(node, 0, UseInfo::AnyTagged());
         ProcessRemainingInputs(node, 1);
         SetOutput(node, NodeOutputInfo::AnyTagged());
         break;
       }
       case IrOpcode::kLoadField: {
         FieldAccess access = FieldAccessOf(node->op());
@@ skipping 423 matching lines @@
 }
 
 
 void SimplifiedLowering::DoStoreBuffer(Node* node) {
   DCHECK_EQ(IrOpcode::kStoreBuffer, node->opcode());
   MachineRepresentation const rep =
       BufferAccessOf(node->op()).machine_type().representation();
   NodeProperties::ChangeOp(node, machine()->CheckedStore(rep));
 }
 
-
-Node* SimplifiedLowering::StringComparison(Node* node) {
-  Operator::Properties properties = node->op()->properties();
-  Callable callable = CodeFactory::StringCompare(isolate());
-  CallDescriptor::Flags flags = CallDescriptor::kNoFlags;
-  CallDescriptor* desc = Linkage::GetStubCallDescriptor(
-      isolate(), zone(), callable.descriptor(), 0, flags, properties);
-  return graph()->NewNode(
-      common()->Call(desc), jsgraph()->HeapConstant(callable.code()),
-      NodeProperties::GetValueInput(node, 0),
-      NodeProperties::GetValueInput(node, 1), jsgraph()->NoContextConstant(),
-      NodeProperties::GetEffectInput(node),
-      NodeProperties::GetControlInput(node));
-}
-
-
 Node* SimplifiedLowering::Int32Div(Node* const node) {
   Int32BinopMatcher m(node);
   Node* const zero = jsgraph()->Int32Constant(0);
   Node* const minus_one = jsgraph()->Int32Constant(-1);
   Node* const lhs = m.left().node();
   Node* const rhs = m.right().node();
 
   if (m.right().Is(-1)) {
     return graph()->NewNode(machine()->Int32Sub(), zero, lhs);
   } else if (m.right().Is(0)) {
@@ skipping 242 matching lines @@
 void SimplifiedLowering::DoShift(Node* node, Operator const* op,
                                  Type* rhs_type) {
   Node* const rhs = NodeProperties::GetValueInput(node, 1);
   if (!rhs_type->Is(type_cache_.kZeroToThirtyOne)) {
     node->ReplaceInput(1, graph()->NewNode(machine()->Word32And(), rhs,
                                            jsgraph()->Int32Constant(0x1f)));
   }
   NodeProperties::ChangeOp(node, op);
 }
 
-
-namespace {
-
-void ReplaceEffectUses(Node* node, Node* replacement) {
-  // Requires distinguishing between value and effect edges.
-  DCHECK(replacement->op()->EffectOutputCount() > 0);
-  for (Edge edge : node->use_edges()) {
-    if (NodeProperties::IsEffectEdge(edge)) {
-      edge.UpdateTo(replacement);
-    } else {
-      DCHECK(NodeProperties::IsValueEdge(edge));
-    }
-  }
-}
-
-}  // namespace
-
-
-void SimplifiedLowering::DoStringLessThan(Node* node) {
-  Node* comparison = StringComparison(node);
-  ReplaceEffectUses(node, comparison);
-  node->ReplaceInput(0, comparison);
-  node->ReplaceInput(1, jsgraph()->SmiConstant(EQUAL));
-  node->TrimInputCount(2);
-  NodeProperties::ChangeOp(node, machine()->IntLessThan());
-}
-
-
-void SimplifiedLowering::DoStringLessThanOrEqual(Node* node) {
-  Node* comparison = StringComparison(node);
-  ReplaceEffectUses(node, comparison);
-  node->ReplaceInput(0, comparison);
-  node->ReplaceInput(1, jsgraph()->SmiConstant(EQUAL));
-  node->TrimInputCount(2);
-  NodeProperties::ChangeOp(node, machine()->IntLessThanOrEqual());
-}
-
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8