Recognize basic block entries in the flow graph.

runtime/vm/intermediate_language.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/intermediate_language.h"
 
 #include "vm/object.h"
 #include "vm/os.h"
 #include "vm/scopes.h"
 
@@ skipping 42 matching lines @@
 void TempValue::Print() const {
   OS::Print("t%d", index_);
 }
 
 
 void ConstantValue::Print() const {
   OS::Print("#%s", instance_.ToCString());
 }
 
 
-void Instruction::PrintGotoSuccessor(
-    Instruction* successor,
-    intptr_t instruction_index,
-    const GrowableArray<Instruction*>& instruction_list) const {
-  if ((instruction_index == 0) ||
-      (instruction_list[instruction_index - 1] != successor)) {
-    // Linear search of the instruction list for the successor's index.
-    for (intptr_t i = 0; i < instruction_list.length(); ++i) {
-      if (instruction_list[i] == successor) {
-        intptr_t instruction_number = instruction_list.length() - i;
-        OS::Print(" goto %d", instruction_number);
-        break;
-      }
-    }
+Instruction* DoInstr::Print() const {
+  OS::Print("    ");
+  computation_->Print();
+  return successor_;
+}
+
+
+Instruction* BindInstr::Print() const {
+  OS::Print("    t%d <-", temp_index_);
+  computation_->Print();
+  return successor_;
+}
+
+
+Instruction* ReturnInstr::Print() const {
+  OS::Print("    return ");
+  value_->Print();
+  return NULL;
+}
+
+
+Instruction* BranchInstr::Print() const {
+  OS::Print("    if ");
+  value_->Print();
+  OS::Print(" goto(%d, %d)", true_successor_->GetBlockNumber(),
+            false_successor_->GetBlockNumber());
+  return NULL;
+}
+
+
+Instruction* JoinEntryInstr::Print() const {
+  OS::Print("%2d: [join]", block_number_);
+  return successor_;
+}
+
+
+Instruction* TargetEntryInstr::Print() const {
+  OS::Print("%2d: [target]", block_number_);
+  return successor_;
+}
+
+
+void DoInstr::Postorder(GrowableArray<Instruction*>* block_entries) {
+  flip_mark();
+  if (successor_->mark() != mark()) successor_->Postorder(block_entries);
+}
+
+
+void BindInstr::Postorder(GrowableArray<Instruction*>* block_entries) {
+  flip_mark();
+  if (successor_->mark() != mark()) successor_->Postorder(block_entries);
+}
+
+
+void ReturnInstr::Postorder(GrowableArray<Instruction*>* block_entries) {
+  flip_mark();
+}
+
+
+void BranchInstr::Postorder(GrowableArray<Instruction*>* block_entries) {
+  flip_mark();
+  // Visit the false successor before the true successor so they appear in
+  // true/false order in reverse postorder.
+  if (false_successor_->mark() != mark()) {
+    false_successor_->Postorder(block_entries);
+  }
+  if (true_successor_->mark() != mark()) {
+    true_successor_->Postorder(block_entries);
   }
 }
 
 
-void DoInstr::Print(intptr_t instruction_index,
-                    const GrowableArray<Instruction*>& instruction_list) const {
-  computation_->Print();
-  PrintGotoSuccessor(successor_, instruction_index, instruction_list);
+void JoinEntryInstr::Postorder(GrowableArray<Instruction*>* block_entries) {
+  flip_mark();
+  if (successor_->mark() != mark()) successor_->Postorder(block_entries);
+  block_entries->Add(this);
 }
 
 
-void BindInstr::Print(
-    intptr_t instruction_index,
-    const GrowableArray<Instruction*>& instruction_list) const {
-  OS::Print("t%d <-", temp_index_);
-  computation_->Print();
-  PrintGotoSuccessor(successor_, instruction_index, instruction_list);
+void TargetEntryInstr::Postorder(GrowableArray<Instruction*>* block_entries) {
+  flip_mark();
+  if (successor_->mark() != mark()) successor_->Postorder(block_entries);
+  block_entries->Add(this);
 }
 
 
-void ReturnInstr::Print(
-    intptr_t instruction_index,
-    const GrowableArray<Instruction*>& instruction_list) const {
-  OS::Print("return ");
-  value_->Print();
-}
-
-
-void BranchInstr::Print(
-    intptr_t instruction_index,
-    const GrowableArray<Instruction*>& instruction_list) const {
-  OS::Print("if ");
-  value_->Print();
-  // Linear search for the instruction numbers of the successors.
-  intptr_t true_successor_number = -1;
-  intptr_t false_successor_number = -1;
-  for (intptr_t i = 0; i < instruction_list.length(); ++i) {
-    if (instruction_list[i] == true_successor_) {
-      true_successor_number = instruction_list.length() - i;
-      if (false_successor_number >= 0) break;
-    }
-    if (instruction_list[i] == false_successor_) {
-      false_successor_number = instruction_list.length() - i;
-      if (true_successor_number >= 0) break;
-    }
-  }
-  OS::Print(" goto(%d, %d)", true_successor_number, false_successor_number);
-}
-
-
-void JoinEntryInstr::Print(
-    intptr_t instruction_index,
-    const GrowableArray<Instruction*>& instruction_list) const {
-  OS::Print("[join]");
-  PrintGotoSuccessor(successor_, instruction_index, instruction_list);
-}
-
-
-void TargetEntryInstr::Print(
-    intptr_t instruction_index,
-    const GrowableArray<Instruction*>& instruction_list) const {
-  OS::Print("[target]");
-  PrintGotoSuccessor(successor_, instruction_index, instruction_list);
-}
-
-
-void DoInstr::Postorder(GrowableArray<Instruction*>* visited) {
-  flip_mark();
-  if (successor_->mark() != mark()) successor_->Postorder(visited);
-  visited->Add(this);
-}
-
-
-void BindInstr::Postorder(GrowableArray<Instruction*>* visited) {
-  flip_mark();
-  if (successor_->mark() != mark()) successor_->Postorder(visited);
-  visited->Add(this);
-}
-
-
-void ReturnInstr::Postorder(GrowableArray<Instruction*>* visited) {
-  flip_mark();
-  visited->Add(this);
-}
-
-
-void BranchInstr::Postorder(GrowableArray<Instruction*>* visited) {
-  flip_mark();
-  // Visit the false successor before the true successor so they appear in
-  // true/false order in reverse postorder.
-  if (false_successor_->mark() != mark()) {
-    false_successor_->Postorder(visited);
-  }
-  if (true_successor_->mark() != mark()) {
-    true_successor_->Postorder(visited);
-  }
-  visited->Add(this);
-}
-
-
-void JoinEntryInstr::Postorder(GrowableArray<Instruction*>* visited) {
-  flip_mark();
-  if (successor_->mark() != mark()) successor_->Postorder(visited);
-  visited->Add(this);
-}
-
-
-void TargetEntryInstr::Postorder(GrowableArray<Instruction*>* visited) {
-  flip_mark();
-  if (successor_->mark() != mark()) successor_->Postorder(visited);
-  visited->Add(this);
-}
-
-
 }  // namespace dart