[turbofan] Don't allocate UnallocatedOperands in Zone memory during instruction selection

src/compiler/mips/instruction-selector-mips.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/base/bits.h"
 #include "src/compiler/instruction-selector-impl.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/node-properties.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
 #define TRACE_UNIMPL() \
   PrintF("UNIMPLEMENTED instr_sel: %s at line %d\n", __FUNCTION__, __LINE__)
 
 #define TRACE() PrintF("instr_sel: %s at line %d\n", __FUNCTION__, __LINE__)
 
 
 // Adds Mips-specific methods for generating InstructionOperands.
 class MipsOperandGenerator FINAL : public OperandGenerator {
  public:
   explicit MipsOperandGenerator(InstructionSelector* selector)
       : OperandGenerator(selector) {}
 
-  InstructionOperand* UseOperand(Node* node, InstructionCode opcode) {
+  InstructionOperand UseOperand(Node* node, InstructionCode opcode) {
     if (CanBeImmediate(node, opcode)) {
       return UseImmediate(node);
     }
     return UseRegister(node);
   }
 
   bool CanBeImmediate(Node* node, InstructionCode opcode) {
     Int32Matcher m(node);
     if (!m.HasValue()) return false;
     int32_t value = m.Value();
@@ skipping 47 matching lines @@
   selector->Emit(opcode, g.DefineAsRegister(node),
                  g.UseRegister(node->InputAt(0)),
                  g.UseOperand(node->InputAt(1), opcode));
 }
 
 
 static void VisitBinop(InstructionSelector* selector, Node* node,
                        InstructionCode opcode, FlagsContinuation* cont) {
   MipsOperandGenerator g(selector);
   Int32BinopMatcher m(node);
-  InstructionOperand* inputs[4];
+  InstructionOperand inputs[4];
   size_t input_count = 0;
-  InstructionOperand* outputs[2];
+  InstructionOperand outputs[2];
   size_t output_count = 0;
 
   inputs[input_count++] = g.UseRegister(m.left().node());
   inputs[input_count++] = g.UseOperand(m.right().node(), opcode);
 
   if (cont->IsBranch()) {
     inputs[input_count++] = g.Label(cont->true_block());
     inputs[input_count++] = g.Label(cont->false_block());
   }
 
@@ skipping 48 matching lines @@
       break;
     default:
       UNREACHABLE();
       return;
   }
 
   if (g.CanBeImmediate(index, opcode)) {
     Emit(opcode | AddressingModeField::encode(kMode_MRI),
          g.DefineAsRegister(node), g.UseRegister(base), g.UseImmediate(index));
   } else {
-    InstructionOperand* addr_reg = g.TempRegister();
+    InstructionOperand addr_reg = g.TempRegister();
     Emit(kMipsAdd | AddressingModeField::encode(kMode_None), addr_reg,
          g.UseRegister(index), g.UseRegister(base));
     // Emit desired load opcode, using temp addr_reg.
     Emit(opcode | AddressingModeField::encode(kMode_MRI),
          g.DefineAsRegister(node), addr_reg, g.TempImmediate(0));
   }
 }
 
 
 void InstructionSelector::VisitStore(Node* node) {
   MipsOperandGenerator g(this);
   Node* base = node->InputAt(0);
   Node* index = node->InputAt(1);
   Node* value = node->InputAt(2);
 
   StoreRepresentation store_rep = OpParameter<StoreRepresentation>(node);
   MachineType rep = RepresentationOf(store_rep.machine_type());
   if (store_rep.write_barrier_kind() == kFullWriteBarrier) {
     DCHECK(rep == kRepTagged);
     // TODO(dcarney): refactor RecordWrite function to take temp registers
     //                and pass them here instead of using fixed regs
     // TODO(dcarney): handle immediate indices.
-    InstructionOperand* temps[] = {g.TempRegister(t1), g.TempRegister(t2)};
-    Emit(kMipsStoreWriteBarrier, NULL, g.UseFixed(base, t0),
+    InstructionOperand temps[] = {g.TempRegister(t1), g.TempRegister(t2)};
+    Emit(kMipsStoreWriteBarrier, g.NoOutput(), g.UseFixed(base, t0),
          g.UseFixed(index, t1), g.UseFixed(value, t2), arraysize(temps), temps);
     return;
   }
   DCHECK_EQ(kNoWriteBarrier, store_rep.write_barrier_kind());
 
   ArchOpcode opcode;
   switch (rep) {
     case kRepFloat32:
       opcode = kMipsSwc1;
       break;
@@ skipping 10 matching lines @@
     case kRepTagged:  // Fall through.
     case kRepWord32:
       opcode = kMipsSw;
       break;
     default:
       UNREACHABLE();
       return;
   }
 
   if (g.CanBeImmediate(index, opcode)) {
-    Emit(opcode | AddressingModeField::encode(kMode_MRI), NULL,
+    Emit(opcode | AddressingModeField::encode(kMode_MRI), g.NoOutput(),
          g.UseRegister(base), g.UseImmediate(index), g.UseRegister(value));
   } else {
-    InstructionOperand* addr_reg = g.TempRegister();
+    InstructionOperand addr_reg = g.TempRegister();
     Emit(kMipsAdd | AddressingModeField::encode(kMode_None), addr_reg,
          g.UseRegister(index), g.UseRegister(base));
     // Emit desired store opcode, using temp addr_reg.
-    Emit(opcode | AddressingModeField::encode(kMode_MRI), NULL, addr_reg,
-         g.TempImmediate(0), g.UseRegister(value));
+    Emit(opcode | AddressingModeField::encode(kMode_MRI), g.NoOutput(),
+         addr_reg, g.TempImmediate(0), g.UseRegister(value));
   }
 }
 
 
 void InstructionSelector::VisitWord32And(Node* node) {
   VisitBinop(this, node, kMipsAnd);
 }
 
 
 void InstructionSelector::VisitWord32Or(Node* node) {
@@ skipping 44 matching lines @@
   Int32BinopMatcher m(node);
   if (m.right().HasValue() && m.right().Value() > 0) {
     int32_t value = m.right().Value();
     if (base::bits::IsPowerOfTwo32(value)) {
       Emit(kMipsShl | AddressingModeField::encode(kMode_None),
            g.DefineAsRegister(node), g.UseRegister(m.left().node()),
            g.TempImmediate(WhichPowerOf2(value)));
       return;
     }
     if (base::bits::IsPowerOfTwo32(value - 1)) {
-      InstructionOperand* temp = g.TempRegister();
+      InstructionOperand temp = g.TempRegister();
       Emit(kMipsShl | AddressingModeField::encode(kMode_None), temp,
            g.UseRegister(m.left().node()),
            g.TempImmediate(WhichPowerOf2(value - 1)));
       Emit(kMipsAdd | AddressingModeField::encode(kMode_None),
            g.DefineAsRegister(node), g.UseRegister(m.left().node()), temp);
       return;
     }
     if (base::bits::IsPowerOfTwo32(value + 1)) {
-      InstructionOperand* temp = g.TempRegister();
+      InstructionOperand temp = g.TempRegister();
       Emit(kMipsShl | AddressingModeField::encode(kMode_None), temp,
            g.UseRegister(m.left().node()),
            g.TempImmediate(WhichPowerOf2(value + 1)));
       Emit(kMipsSub | AddressingModeField::encode(kMode_None),
            g.DefineAsRegister(node), temp, g.UseRegister(m.left().node()));
       return;
     }
   }
   Emit(kMipsMul, g.DefineAsRegister(node), g.UseRegister(m.left().node()),
        g.UseRegister(m.right().node()));
@@ skipping 146 matching lines @@
         GetFrameStateDescriptor(node->InputAt(descriptor->InputCount()));
   }
 
   CallBuffer buffer(zone(), descriptor, frame_state_descriptor);
 
   // Compute InstructionOperands for inputs and outputs.
   InitializeCallBuffer(node, &buffer, true, false);
   // Possibly align stack here for functions.
   int push_count = buffer.pushed_nodes.size();
   if (push_count > 0) {
-    Emit(kMipsStackClaim | MiscField::encode(push_count), NULL);
+    Emit(kMipsStackClaim | MiscField::encode(push_count), g.NoOutput());
   }
   int slot = buffer.pushed_nodes.size() - 1;
   for (auto i = buffer.pushed_nodes.rbegin(); i != buffer.pushed_nodes.rend();
        ++i) {
-    Emit(kMipsStoreToStackSlot | MiscField::encode(slot), nullptr,
+    Emit(kMipsStoreToStackSlot | MiscField::encode(slot), g.NoOutput(),
          g.UseRegister(*i));
     slot--;
   }
 
   // Select the appropriate opcode based on the call type.
   InstructionCode opcode;
   switch (descriptor->kind()) {
     case CallDescriptor::kCallCodeObject: {
       opcode = kArchCallCodeObject;
       break;
     }
     case CallDescriptor::kCallJSFunction:
       opcode = kArchCallJSFunction;
       break;
     default:
       UNREACHABLE();
       return;
   }
   opcode |= MiscField::encode(descriptor->flags());
 
   // Emit the call instruction.
-  InstructionOperand** first_output =
+  InstructionOperand* first_output =
       buffer.outputs.size() > 0 ? &buffer.outputs.front() : NULL;
   Instruction* call_instr =
       Emit(opcode, buffer.outputs.size(), first_output,
            buffer.instruction_args.size(), &buffer.instruction_args.front());
   call_instr->MarkAsCall();
 }
 
 
 void InstructionSelector::VisitCheckedLoad(Node* node) {
   MachineType rep = RepresentationOf(OpParameter<MachineType>(node));
@@ skipping 16 matching lines @@
     case kRepFloat32:
       opcode = kCheckedLoadFloat32;
       break;
     case kRepFloat64:
       opcode = kCheckedLoadFloat64;
       break;
     default:
       UNREACHABLE();
       return;
   }
-  InstructionOperand* offset_operand = g.CanBeImmediate(offset, opcode)
-                                           ? g.UseImmediate(offset)
-                                           : g.UseRegister(offset);
+  InstructionOperand offset_operand = g.CanBeImmediate(offset, opcode)
+                                          ? g.UseImmediate(offset)
+                                          : g.UseRegister(offset);
 
-  InstructionOperand* length_operand =
-      (!g.CanBeImmediate(offset, opcode)) ? g.CanBeImmediate(length, opcode)
-      ? g.UseImmediate(length)
-      : g.UseRegister(length)
-      : g.UseRegister(length);
+  InstructionOperand length_operand = (!g.CanBeImmediate(offset, opcode))
+                                          ? g.CanBeImmediate(length, opcode)
+                                                ? g.UseImmediate(length)
+                                                : g.UseRegister(length)
+                                          : g.UseRegister(length);
 
   Emit(opcode | AddressingModeField::encode(kMode_MRI),
        g.DefineAsRegister(node), offset_operand, length_operand,
        g.UseRegister(buffer));
 }
 
 
 void InstructionSelector::VisitCheckedStore(Node* node) {
   MachineType rep = RepresentationOf(OpParameter<MachineType>(node));
   MipsOperandGenerator g(this);
@@ skipping 15 matching lines @@
     case kRepFloat32:
       opcode = kCheckedStoreFloat32;
       break;
     case kRepFloat64:
       opcode = kCheckedStoreFloat64;
       break;
     default:
       UNREACHABLE();
       return;
   }
-  InstructionOperand* offset_operand = g.CanBeImmediate(offset, opcode)
-                                           ? g.UseImmediate(offset)
-                                           : g.UseRegister(offset);
+  InstructionOperand offset_operand = g.CanBeImmediate(offset, opcode)
+                                          ? g.UseImmediate(offset)
+                                          : g.UseRegister(offset);
 
-  InstructionOperand* length_operand =
-      (!g.CanBeImmediate(offset, opcode)) ? g.CanBeImmediate(length, opcode)
-      ? g.UseImmediate(length)
-      : g.UseRegister(length)
-      : g.UseRegister(length);
+  InstructionOperand length_operand = (!g.CanBeImmediate(offset, opcode))
+                                          ? g.CanBeImmediate(length, opcode)
+                                                ? g.UseImmediate(length)
+                                                : g.UseRegister(length)
+                                          : g.UseRegister(length);
 
-  Emit(opcode | AddressingModeField::encode(kMode_MRI), nullptr, offset_operand,
-       length_operand, g.UseRegister(value), g.UseRegister(buffer));
+  Emit(opcode | AddressingModeField::encode(kMode_MRI), g.NoOutput(),
+       offset_operand, length_operand, g.UseRegister(value),
+       g.UseRegister(buffer));
 }
 
 
 namespace {
 
 // Shared routine for multiple compare operations.
 static void VisitCompare(InstructionSelector* selector, InstructionCode opcode,
-                         InstructionOperand* left, InstructionOperand* right,
+                         InstructionOperand left, InstructionOperand right,
                          FlagsContinuation* cont) {
   MipsOperandGenerator g(selector);
   opcode = cont->Encode(opcode);
   if (cont->IsBranch()) {
-    selector->Emit(opcode, NULL, left, right, g.Label(cont->true_block()),
+    selector->Emit(opcode, g.NoOutput(), left, right,
+                   g.Label(cont->true_block()),
                    g.Label(cont->false_block()))->MarkAsControl();
   } else {
     DCHECK(cont->IsSet());
     // TODO(plind): Revisit and test this path.
     selector->Emit(opcode, g.DefineAsRegister(cont->result()), left, right);
   }
 }
 
 
 // Shared routine for multiple float compare operations.
@@ skipping 106 matching lines @@
         return VisitWordCompare(selector, value, kMipsTst, cont, true);
       default:
         break;
     }
     break;
   }
 
   // Continuation could not be combined with a compare, emit compare against 0.
   MipsOperandGenerator g(selector);
   InstructionCode const opcode = cont->Encode(kMipsCmp);
-  InstructionOperand* const value_operand = g.UseRegister(value);
+  InstructionOperand const value_operand = g.UseRegister(value);
   if (cont->IsBranch()) {
-    selector->Emit(opcode, nullptr, value_operand, g.TempImmediate(0),
+    selector->Emit(opcode, g.NoOutput(), value_operand, g.TempImmediate(0),
                    g.Label(cont->true_block()),
                    g.Label(cont->false_block()))->MarkAsControl();
   } else {
     selector->Emit(opcode, g.DefineAsRegister(cont->result()), value_operand,
                    g.TempImmediate(0));
   }
 }
 
 
 void InstructionSelector::VisitBranch(Node* branch, BasicBlock* tbranch,
@@ skipping 82 matching lines @@
     return MachineOperatorBuilder::kFloat64Floor |
            MachineOperatorBuilder::kFloat64Ceil |
            MachineOperatorBuilder::kFloat64RoundTruncate;
   }
   return MachineOperatorBuilder::kNoFlags;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8