[interpreter] Introduce bytecode generation pipeline.

src/interpreter/bytecode-pipeline.cc

+// Copyright 2015 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/interpreter/bytecode-pipeline.h"
+
+#include <iomanip>
+#include "src/interpreter/source-position-table.h"
+
+namespace v8 {
+namespace internal {
+namespace interpreter {
+
+void BytecodeSourceInfo::Update(const BytecodeSourceInfo& entry) {
+  DCHECK(entry.is_valid());
+  if (!is_valid() || (entry.is_statement() && !is_statement()) ||
+      (entry.is_statement() && is_statement() &&
+       entry.source_position() > source_position())) {
+    // Position is updated if any of the following conditions are met:
+    //   (1) there is no existing position.
+    //   (2) the incoming position is a statement and the current position
+    //       is an expression.
+    //   (3) the existing position is a statement and the incoming
+    //       statement has a later source position.
+    // Condition 3 is needed for the first statement in a function which
+    // may end up with later statement positions being added during bytecode
+    // generation.
+    source_position_ = entry.source_position_;
+    is_statement_ = entry.is_statement_;
+  }
+}
+
+BytecodeNode::BytecodeNode(Bytecode bytecode) {
+  DCHECK_EQ(Bytecodes::NumberOfOperands(bytecode), 0);
+  bytecode_ = bytecode;
+  operand_scale_ = OperandScale::kSingle;
+}
+
+BytecodeNode::BytecodeNode(Bytecode bytecode, uint32_t operand0,
+                           OperandScale operand_scale) {
+  DCHECK_EQ(Bytecodes::NumberOfOperands(bytecode), 1);
+  bytecode_ = bytecode;
+  operands_[0] = operand0;
+  operand_scale_ = operand_scale;
+}
+
+BytecodeNode::BytecodeNode(Bytecode bytecode, uint32_t operand0,
+                           uint32_t operand1, OperandScale operand_scale) {
+  DCHECK_EQ(Bytecodes::NumberOfOperands(bytecode), 2);
+  bytecode_ = bytecode;
+  operands_[0] = operand0;
+  operands_[1] = operand1;
+  operand_scale_ = operand_scale;
+}
+
+BytecodeNode::BytecodeNode(Bytecode bytecode, uint32_t operand0,
+                           uint32_t operand1, uint32_t operand2,
+                           OperandScale operand_scale) {
+  DCHECK_EQ(Bytecodes::NumberOfOperands(bytecode), 3);
+  bytecode_ = bytecode;
+  operands_[0] = operand0;
+  operands_[1] = operand1;
+  operands_[2] = operand2;
+  operand_scale_ = operand_scale;
+}
+
+BytecodeNode::BytecodeNode(Bytecode bytecode, uint32_t operand0,
+                           uint32_t operand1, uint32_t operand2,
+                           uint32_t operand3, OperandScale operand_scale) {
+  DCHECK_EQ(Bytecodes::NumberOfOperands(bytecode), 4);
+  bytecode_ = bytecode;
+  operands_[0] = operand0;
+  operands_[1] = operand1;
+  operands_[2] = operand2;
+  operands_[3] = operand3;
+  operand_scale_ = operand_scale;
+}
+
+void BytecodeNode::set_bytecode(Bytecode bytecode) {
+  DCHECK_EQ(Bytecodes::NumberOfOperands(bytecode), 0);
+  bytecode_ = bytecode;
+  operand_scale_ = OperandScale::kSingle;
+}
+
+void BytecodeNode::set_bytecode(Bytecode bytecode, uint32_t operand0,
+                                OperandScale operand_scale) {
+  DCHECK_EQ(Bytecodes::NumberOfOperands(bytecode), 1);
+  bytecode_ = bytecode;
+  operands_[0] = operand0;
+  operand_scale_ = operand_scale;
+}
+
+size_t BytecodeNode::Size() const {
+  size_t size = Bytecodes::Size(bytecode_, operand_scale_);
+  if (Bytecodes::OperandScaleRequiresPrefixBytecode(operand_scale_)) {
+    size += 1;
+  }
+  return size;
+}
+
+void BytecodeNode::Print(std::ostream& os) const {
+#ifdef DEBUG
+  std::ios saved_state(nullptr);
+  saved_state.copyfmt(os);
+
+  os << Bytecodes::ToString(bytecode_);
+  if (Bytecodes::OperandScaleRequiresPrefixBytecode(operand_scale_)) {
+    Bytecode scale_prefix =
+        Bytecodes::OperandScaleToPrefixBytecode(operand_scale_);
+    os << '.' << Bytecodes::ToString(scale_prefix);
+  }
+
+  for (int i = 0; i < operand_count(); ++i) {
+    os << ' ' << std::setw(8) << std::setfill('0') << std::hex << operands_[i];
+  }
+  os.copyfmt(saved_state);
+
+  if (source_info_.is_valid()) {
+    os << source_info_;
+  }
+  os << '\n';
+#else
+  os << static_cast<const void*>(this);
+#endif  // DEBUG
+}
+
+void BytecodeNode::Clone(const BytecodeNode* const other) {
+  memcpy(this, other, sizeof(*other));
+}
+
+bool BytecodeNode::operator==(const BytecodeNode& other) const {
+  if (this == &other) {
+    return true;
+  } else if (this->bytecode() != other.bytecode() ||
+             this->source_info() != other.source_info()) {
+    return false;
+  } else {
+    for (int i = 0; i < this->operand_count(); ++i) {
+      if (this->operand(i) != other.operand(i)) {
+        return false;
+      }
+    }
+  }
+  return true;
+}
+
+std::ostream& operator<<(std::ostream& os, const BytecodeNode& node) {
+  node.Print(os);
+  return os;
+}
+
+std::ostream& operator<<(std::ostream& os, const BytecodeSourceInfo& info) {
+  if (info.is_valid()) {
+    char description = info.is_statement() ? 'S' : 'E';
+    os << info.source_position() << ' ' << description << '>';
+  }
+  return os;
+}
+
+}  // namespace interpreter
+}  // namespace internal
+}  // namespace v8