Remove obsolete support for an experimental multipass compiler.

src/cfg.cc

Index: src/cfg.cc
===================================================================
--- src/cfg.cc	(revision 2994)
+++ src/cfg.cc	(working copy)
@@ -1,758 +0,0 @@
-// Copyright 2009 the V8 project authors. All rights reserved.
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-//       notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-//       copyright notice, this list of conditions and the following
-//       disclaimer in the documentation and/or other materials provided
-//       with the distribution.
-//     * Neither the name of Google Inc. nor the names of its
-//       contributors may be used to endorse or promote products derived
-//       from this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#include "v8.h"
-
-#include "bootstrapper.h"
-#include "cfg.h"
-#include "scopeinfo.h"
-#include "scopes.h"
-
-namespace v8 {
-namespace internal {
-
-
-CfgGlobals* CfgGlobals::top_ = NULL;
-
-
-CfgGlobals::CfgGlobals(FunctionLiteral* fun)
-    : global_fun_(fun),
-      global_exit_(new ExitNode()),
-      nowhere_(new Nowhere()),
-#ifdef DEBUG
-      node_counter_(0),
-      temp_counter_(0),
-#endif
-      previous_(top_) {
-  top_ = this;
-}
-
-
-#define BAILOUT(reason)                         \
-  do { return NULL; } while (false)
-
-Cfg* Cfg::Build() {
-  FunctionLiteral* fun = CfgGlobals::current()->fun();
-  if (fun->scope()->num_heap_slots() > 0) {
-    BAILOUT("function has context slots");
-  }
-  if (fun->scope()->num_stack_slots() > kBitsPerPointer) {
-    BAILOUT("function has too many locals");
-  }
-  if (fun->scope()->num_parameters() > kBitsPerPointer - 1) {
-    BAILOUT("function has too many parameters");
-  }
-  if (fun->scope()->arguments() != NULL) {
-    BAILOUT("function uses .arguments");
-  }
-
-  ZoneList<Statement*>* body = fun->body();
-  if (body->is_empty()) {
-    BAILOUT("empty function body");
-  }
-
-  StatementCfgBuilder builder;
-  builder.VisitStatements(body);
-  Cfg* graph = builder.graph();
-  if (graph == NULL) {
-    BAILOUT("unsupported statement type");
-  }
-  if (graph->is_empty()) {
-    BAILOUT("function body produces empty cfg");
-  }
-  if (graph->has_exit()) {
-    BAILOUT("control path without explicit return");
-  }
-  graph->PrependEntryNode();
-  return graph;
-}
-
-#undef BAILOUT
-
-
-void Cfg::PrependEntryNode() {
-  ASSERT(!is_empty());
-  entry_ = new EntryNode(InstructionBlock::cast(entry()));
-}
-
-
-void Cfg::Append(Instruction* instr) {
-  ASSERT(is_empty() || has_exit());
-  if (is_empty()) {
-    entry_ = exit_ = new InstructionBlock();
-  }
-  InstructionBlock::cast(exit_)->Append(instr);
-}
-
-
-void Cfg::AppendReturnInstruction(Value* value) {
-  Append(new ReturnInstr(value));
-  ExitNode* global_exit = CfgGlobals::current()->exit();
-  InstructionBlock::cast(exit_)->set_successor(global_exit);
-  exit_ = NULL;
-}
-
-
-void Cfg::Concatenate(Cfg* other) {
-  ASSERT(is_empty() || has_exit());
-  if (other->is_empty()) return;
-
-  if (is_empty()) {
-    entry_ = other->entry();
-    exit_ = other->exit();
-  } else {
-    // We have a pair of nonempty fragments and this has an available exit.
-    // Destructively glue the fragments together.
-    InstructionBlock* first = InstructionBlock::cast(exit_);
-    InstructionBlock* second = InstructionBlock::cast(other->entry());
-    first->instructions()->AddAll(*second->instructions());
-    if (second->successor() != NULL) {
-      first->set_successor(second->successor());
-      exit_ = other->exit();
-    }
-  }
-}
-
-
-void InstructionBlock::Unmark() {
-  if (is_marked_) {
-    is_marked_ = false;
-    successor_->Unmark();
-  }
-}
-
-
-void EntryNode::Unmark() {
-  if (is_marked_) {
-    is_marked_ = false;
-    successor_->Unmark();
-  }
-}
-
-
-void ExitNode::Unmark() {
-  is_marked_ = false;
-}
-
-
-Handle<Code> Cfg::Compile(Handle<Script> script) {
-  const int kInitialBufferSize = 4 * KB;
-  MacroAssembler* masm = new MacroAssembler(NULL, kInitialBufferSize);
-  entry()->Compile(masm);
-  entry()->Unmark();
-  CodeDesc desc;
-  masm->GetCode(&desc);
-  FunctionLiteral* fun = CfgGlobals::current()->fun();
-  ZoneScopeInfo info(fun->scope());
-  InLoopFlag in_loop = fun->loop_nesting() ? IN_LOOP : NOT_IN_LOOP;
-  Code::Flags flags = Code::ComputeFlags(Code::FUNCTION, in_loop);
-  Handle<Code> code = Factory::NewCode(desc, &info, flags, masm->CodeObject());
-
-  // Add unresolved entries in the code to the fixup list.
-  Bootstrapper::AddFixup(*code, masm);
-
-#ifdef ENABLE_DISASSEMBLER
-  if (FLAG_print_code) {
-    // Print the source code if available.
-    if (!script->IsUndefined() && !script->source()->IsUndefined()) {
-      PrintF("--- Raw source ---\n");
-      StringInputBuffer stream(String::cast(script->source()));
-      stream.Seek(fun->start_position());
-      // fun->end_position() points to the last character in the
-      // stream. We need to compensate by adding one to calculate the
-      // length.
-      int source_len = fun->end_position() - fun->start_position() + 1;
-      for (int i = 0; i < source_len; i++) {
-        if (stream.has_more()) PrintF("%c", stream.GetNext());
-      }
-      PrintF("\n\n");
-    }
-    PrintF("--- Code ---\n");
-    code->Disassemble(*fun->name()->ToCString());
-  }
-#endif
-
-  return code;
-}
-
-
-void ZeroOperandInstruction::FastAllocate(TempLocation* temp) {
-  temp->set_where(TempLocation::STACK);
-}
-
-
-void OneOperandInstruction::FastAllocate(TempLocation* temp) {
-  temp->set_where((temp == value_)
-                  ? TempLocation::ACCUMULATOR
-                  : TempLocation::STACK);
-}
-
-
-void TwoOperandInstruction::FastAllocate(TempLocation* temp) {
-  temp->set_where((temp == value0_ || temp == value1_)
-                  ? TempLocation::ACCUMULATOR
-                  : TempLocation::STACK);
-}
-
-
-void PositionInstr::Compile(MacroAssembler* masm) {
-  if (FLAG_debug_info && pos_ != RelocInfo::kNoPosition) {
-    masm->RecordStatementPosition(pos_);
-    masm->RecordPosition(pos_);
-  }
-}
-
-
-void MoveInstr::Compile(MacroAssembler* masm) {
-  location()->Move(masm, value());
-}
-
-
-// The expression builder should not be used for declarations or statements.
-void ExpressionCfgBuilder::VisitDeclaration(Declaration* decl) {
-  UNREACHABLE();
-}
-
-#define DEFINE_VISIT(type)                                              \
-  void ExpressionCfgBuilder::Visit##type(type* stmt) { UNREACHABLE(); }
-STATEMENT_NODE_LIST(DEFINE_VISIT)
-#undef DEFINE_VISIT
-
-
-// Macros (temporarily) handling unsupported expression types.
-#define BAILOUT(reason)                         \
-  do {                                          \
-    graph_ = NULL;                              \
-    return;                                     \
-  } while (false)
-
-void ExpressionCfgBuilder::VisitFunctionLiteral(FunctionLiteral* expr) {
-  BAILOUT("FunctionLiteral");
-}
-
-
-void ExpressionCfgBuilder::VisitFunctionBoilerplateLiteral(
-    FunctionBoilerplateLiteral* expr) {
-  BAILOUT("FunctionBoilerplateLiteral");
-}
-
-
-void ExpressionCfgBuilder::VisitConditional(Conditional* expr) {
-  BAILOUT("Conditional");
-}
-
-
-void ExpressionCfgBuilder::VisitSlot(Slot* expr) {
-  BAILOUT("Slot");
-}
-
-
-void ExpressionCfgBuilder::VisitVariableProxy(VariableProxy* expr) {
-  Expression* rewrite = expr->var()->rewrite();
-  if (rewrite == NULL || rewrite->AsSlot() == NULL) {
-    BAILOUT("unsupported variable (not a slot)");
-  }
-  Slot* slot = rewrite->AsSlot();
-  if (slot->type() != Slot::PARAMETER && slot->type() != Slot::LOCAL) {
-    BAILOUT("unsupported slot type (not a parameter or local)");
-  }
-  // Ignore the passed destination.
-  value_ = new SlotLocation(slot->type(), slot->index());
-}
-
-
-void ExpressionCfgBuilder::VisitLiteral(Literal* expr) {
-  // Ignore the passed destination.
-  value_ = new Constant(expr->handle());
-}
-
-
-void ExpressionCfgBuilder::VisitRegExpLiteral(RegExpLiteral* expr) {
-  BAILOUT("RegExpLiteral");
-}
-
-
-void ExpressionCfgBuilder::VisitObjectLiteral(ObjectLiteral* expr) {
-  BAILOUT("ObjectLiteral");
-}
-
-
-void ExpressionCfgBuilder::VisitArrayLiteral(ArrayLiteral* expr) {
-  BAILOUT("ArrayLiteral");
-}
-
-
-void ExpressionCfgBuilder::VisitCatchExtensionObject(
-    CatchExtensionObject* expr) {
-  BAILOUT("CatchExtensionObject");
-}
-
-
-void ExpressionCfgBuilder::VisitAssignment(Assignment* expr) {
-  if (expr->op() != Token::ASSIGN && expr->op() != Token::INIT_VAR) {
-    BAILOUT("unsupported compound assignment");
-  }
-  Expression* lhs = expr->target();
-  if (lhs->AsProperty() != NULL) {
-    BAILOUT("unsupported property assignment");
-  }
-
-  Variable* var = lhs->AsVariableProxy()->AsVariable();
-  if (var == NULL) {
-    BAILOUT("unsupported invalid left-hand side");
-  }
-  if (var->is_global()) {
-    BAILOUT("unsupported global variable");
-  }
-  Slot* slot = var->slot();
-  ASSERT(slot != NULL);
-  if (slot->type() != Slot::PARAMETER && slot->type() != Slot::LOCAL) {
-    BAILOUT("unsupported slot lhs (not a parameter or local)");
-  }
-
-  // Parameter and local slot assignments.
-  ExpressionCfgBuilder builder;
-  SlotLocation* loc = new SlotLocation(slot->type(), slot->index());
-  builder.Build(expr->value(), loc);
-  if (builder.graph() == NULL) {
-    BAILOUT("unsupported expression in assignment");
-  }
-  // If the expression did not come back in the slot location, append
-  // a move to the CFG.
-  graph_ = builder.graph();
-  if (builder.value() != loc) {
-    graph()->Append(new MoveInstr(loc, builder.value()));
-  }
-  // Record the assignment.
-  assigned_vars_.AddElement(loc);
-  // Ignore the destination passed to us.
-  value_ = loc;
-}
-
-
-void ExpressionCfgBuilder::VisitThrow(Throw* expr) {
-  BAILOUT("Throw");
-}
-
-
-void ExpressionCfgBuilder::VisitProperty(Property* expr) {
-  ExpressionCfgBuilder object, key;
-  object.Build(expr->obj(), NULL);
-  if (object.graph() == NULL) {
-    BAILOUT("unsupported object subexpression in propload");
-  }
-  key.Build(expr->key(), NULL);
-  if (key.graph() == NULL) {
-    BAILOUT("unsupported key subexpression in propload");
-  }
-
-  if (destination_ == NULL) destination_ = new TempLocation();
-
-  graph_ = object.graph();
-  // Insert a move to a fresh temporary if the object value is in a slot
-  // that's assigned in the key.
-  Location* temp = NULL;
-  if (object.value()->is_slot() &&
-      key.assigned_vars()->Contains(SlotLocation::cast(object.value()))) {
-    temp = new TempLocation();
-    graph()->Append(new MoveInstr(temp, object.value()));
-  }
-  graph()->Concatenate(key.graph());
-  graph()->Append(new PropLoadInstr(destination_,
-                                    temp == NULL ? object.value() : temp,
-                                    key.value()));
-
-  assigned_vars_ = *object.assigned_vars();
-  assigned_vars()->Union(key.assigned_vars());
-
-  value_ = destination_;
-}
-
-
-void ExpressionCfgBuilder::VisitCall(Call* expr) {
-  BAILOUT("Call");
-}
-
-
-void ExpressionCfgBuilder::VisitCallNew(CallNew* expr) {
-  BAILOUT("CallNew");
-}
-
-
-void ExpressionCfgBuilder::VisitCallRuntime(CallRuntime* expr) {
-  BAILOUT("CallRuntime");
-}
-
-
-void ExpressionCfgBuilder::VisitUnaryOperation(UnaryOperation* expr) {
-  BAILOUT("UnaryOperation");
-}
-
-
-void ExpressionCfgBuilder::VisitCountOperation(CountOperation* expr) {
-  BAILOUT("CountOperation");
-}
-
-
-void ExpressionCfgBuilder::VisitBinaryOperation(BinaryOperation* expr) {
-  Token::Value op = expr->op();
-  switch (op) {
-    case Token::COMMA:
-    case Token::OR:
-    case Token::AND:
-      BAILOUT("unsupported binary operation");
-
-    case Token::BIT_OR:
-    case Token::BIT_XOR:
-    case Token::BIT_AND:
-    case Token::SHL:
-    case Token::SAR:
-    case Token::SHR:
-    case Token::ADD:
-    case Token::SUB:
-    case Token::MUL:
-    case Token::DIV:
-    case Token::MOD: {
-      ExpressionCfgBuilder left, right;
-      left.Build(expr->left(), NULL);
-      if (left.graph() == NULL) {
-        BAILOUT("unsupported left subexpression in binop");
-      }
-      right.Build(expr->right(), NULL);
-      if (right.graph() == NULL) {
-        BAILOUT("unsupported right subexpression in binop");
-      }
-
-      if (destination_ == NULL) destination_ = new TempLocation();
-
-      graph_ = left.graph();
-      // Insert a move to a fresh temporary if the left value is in a
-      // slot that's assigned on the right.
-      Location* temp = NULL;
-      if (left.value()->is_slot() &&
-          right.assigned_vars()->Contains(SlotLocation::cast(left.value()))) {
-        temp = new TempLocation();
-        graph()->Append(new MoveInstr(temp, left.value()));
-      }
-      graph()->Concatenate(right.graph());
-      graph()->Append(new BinaryOpInstr(destination_, op,
-                                        temp == NULL ? left.value() : temp,
-                                        right.value()));
-
-      assigned_vars_ = *left.assigned_vars();
-      assigned_vars()->Union(right.assigned_vars());
-
-      value_ = destination_;
-      return;
-    }
-
-    default:
-      UNREACHABLE();
-  }
-}
-
-
-void ExpressionCfgBuilder::VisitCompareOperation(CompareOperation* expr) {
-  BAILOUT("CompareOperation");
-}
-
-
-void ExpressionCfgBuilder::VisitThisFunction(ThisFunction* expr) {
-  BAILOUT("ThisFunction");
-}
-
-#undef BAILOUT
-
-
-// Macros (temporarily) handling unsupported statement types.
-#define BAILOUT(reason)                         \
-  do {                                          \
-    graph_ = NULL;                              \
-    return;                                     \
-  } while (false)
-
-#define CHECK_BAILOUT()                         \
-  if (graph() == NULL) { return; } else {}
-
-void StatementCfgBuilder::VisitStatements(ZoneList<Statement*>* stmts) {
-  for (int i = 0, len = stmts->length(); i < len; i++) {
-    Visit(stmts->at(i));
-    CHECK_BAILOUT();
-    if (!graph()->has_exit()) return;
-  }
-}
-
-
-// The statement builder should not be used for declarations or expressions.
-void StatementCfgBuilder::VisitDeclaration(Declaration* decl) { UNREACHABLE(); }
-
-#define DEFINE_VISIT(type)                                      \
-  void StatementCfgBuilder::Visit##type(type* expr) { UNREACHABLE(); }
-EXPRESSION_NODE_LIST(DEFINE_VISIT)
-#undef DEFINE_VISIT
-
-
-void StatementCfgBuilder::VisitBlock(Block* stmt) {
-  VisitStatements(stmt->statements());
-}
-
-
-void StatementCfgBuilder::VisitExpressionStatement(ExpressionStatement* stmt) {
-  ExpressionCfgBuilder builder;
-  builder.Build(stmt->expression(), CfgGlobals::current()->nowhere());
-  if (builder.graph() == NULL) {
-    BAILOUT("unsupported expression in expression statement");
-  }
-  graph()->Append(new PositionInstr(stmt->statement_pos()));
-  graph()->Concatenate(builder.graph());
-}
-
-
-void StatementCfgBuilder::VisitEmptyStatement(EmptyStatement* stmt) {
-  // Nothing to do.
-}
-
-
-void StatementCfgBuilder::VisitIfStatement(IfStatement* stmt) {
-  BAILOUT("IfStatement");
-}
-
-
-void StatementCfgBuilder::VisitContinueStatement(ContinueStatement* stmt) {
-  BAILOUT("ContinueStatement");
-}
-
-
-void StatementCfgBuilder::VisitBreakStatement(BreakStatement* stmt) {
-  BAILOUT("BreakStatement");
-}
-
-
-void StatementCfgBuilder::VisitReturnStatement(ReturnStatement* stmt) {
-  ExpressionCfgBuilder builder;
-  builder.Build(stmt->expression(), NULL);
-  if (builder.graph() == NULL) {
-    BAILOUT("unsupported expression in return statement");
-  }
-
-  graph()->Append(new PositionInstr(stmt->statement_pos()));
-  graph()->Concatenate(builder.graph());
-  graph()->AppendReturnInstruction(builder.value());
-}
-
-
-void StatementCfgBuilder::VisitWithEnterStatement(WithEnterStatement* stmt) {
-  BAILOUT("WithEnterStatement");
-}
-
-
-void StatementCfgBuilder::VisitWithExitStatement(WithExitStatement* stmt) {
-  BAILOUT("WithExitStatement");
-}
-
-
-void StatementCfgBuilder::VisitSwitchStatement(SwitchStatement* stmt) {
-  BAILOUT("SwitchStatement");
-}
-
-
-void StatementCfgBuilder::VisitLoopStatement(LoopStatement* stmt) {
-  BAILOUT("LoopStatement");
-}
-
-
-void StatementCfgBuilder::VisitForInStatement(ForInStatement* stmt) {
-  BAILOUT("ForInStatement");
-}
-
-
-void StatementCfgBuilder::VisitTryCatch(TryCatch* stmt) {
-  BAILOUT("TryCatch");
-}
-
-
-void StatementCfgBuilder::VisitTryFinally(TryFinally* stmt) {
-  BAILOUT("TryFinally");
-}
-
-
-void StatementCfgBuilder::VisitDebuggerStatement(DebuggerStatement* stmt) {
-  BAILOUT("DebuggerStatement");
-}
-
-
-#ifdef DEBUG
-// CFG printing support (via depth-first, preorder block traversal).
-
-void Cfg::Print() {
-  entry_->Print();
-  entry_->Unmark();
-}
-
-
-void Constant::Print() {
-  PrintF("Constant ");
-  handle_->Print();
-}
-
-
-void Nowhere::Print() {
-  PrintF("Nowhere");
-}
-
-
-void SlotLocation::Print() {
-  PrintF("Slot ");
-  switch (type_) {
-    case Slot::PARAMETER:
-      PrintF("(PARAMETER, %d)", index_);
-      break;
-    case Slot::LOCAL:
-      PrintF("(LOCAL, %d)", index_);
-      break;
-    default:
-      UNREACHABLE();
-  }
-}
-
-
-void TempLocation::Print() {
-  PrintF("Temp %d", number());
-}
-
-
-void OneOperandInstruction::Print() {
-  PrintF("(");
-  location()->Print();
-  PrintF(", ");
-  value_->Print();
-  PrintF(")");
-}
-
-
-void TwoOperandInstruction::Print() {
-  PrintF("(");
-  location()->Print();
-  PrintF(", ");
-  value0_->Print();
-  PrintF(", ");
-  value1_->Print();
-  PrintF(")");
-}
-
-
-void MoveInstr::Print() {
-  PrintF("Move              ");
-  OneOperandInstruction::Print();
-  PrintF("\n");
-}
-
-
-void PropLoadInstr::Print() {
-  PrintF("PropLoad          ");
-  TwoOperandInstruction::Print();
-  PrintF("\n");
-}
-
-
-void BinaryOpInstr::Print() {
-  switch (op()) {
-    case Token::OR:
-      // Two character operand.
-      PrintF("BinaryOp[OR]      ");
-      break;
-    case Token::AND:
-    case Token::SHL:
-    case Token::SAR:
-    case Token::SHR:
-    case Token::ADD:
-    case Token::SUB:
-    case Token::MUL:
-    case Token::DIV:
-    case Token::MOD:
-      // Three character operands.
-      PrintF("BinaryOp[%s]     ", Token::Name(op()));
-      break;
-    case Token::COMMA:
-      // Five character operand.
-      PrintF("BinaryOp[COMMA]   ");
-      break;
-    case Token::BIT_OR:
-      // Six character operand.
-      PrintF("BinaryOp[BIT_OR]  ");
-      break;
-    case Token::BIT_XOR:
-    case Token::BIT_AND:
-      // Seven character operands.
-      PrintF("BinaryOp[%s] ", Token::Name(op()));
-      break;
-    default:
-      UNREACHABLE();
-  }
-  TwoOperandInstruction::Print();
-  PrintF("\n");
-}
-
-
-void ReturnInstr::Print() {
-  PrintF("Return            ");
-  OneOperandInstruction::Print();
-  PrintF("\n");
-}
-
-
-void InstructionBlock::Print() {
-  if (!is_marked_) {
-    is_marked_ = true;
-    PrintF("L%d:\n", number());
-    for (int i = 0, len = instructions_.length(); i < len; i++) {
-      instructions_[i]->Print();
-    }
-    PrintF("Goto              L%d\n\n", successor_->number());
-    successor_->Print();
-  }
-}
-
-
-void EntryNode::Print() {
-  if (!is_marked_) {
-    is_marked_ = true;
-    successor_->Print();
-  }
-}
-
-
-void ExitNode::Print() {
-  if (!is_marked_) {
-    is_marked_ = true;
-    PrintF("L%d:\nExit\n\n", number());
-  }
-}
-
-#endif  // DEBUG
-
-} }  // namespace v8::internal