[turbofan] Add support for deferred code.

src/compiler/code-generator.cc

Index: src/compiler/code-generator.cc
diff --git a/src/compiler/code-generator.cc b/src/compiler/code-generator.cc
index 5b3a2db086fcd51309843af177bec8e44701e051..4f278fdcd5a4a5f2fb581f96f8481b7673de2d02 100644
--- a/src/compiler/code-generator.cc
+++ b/src/compiler/code-generator.cc
@@ -44,10 +44,20 @@ Handle<Code> CodeGenerator::GenerateCode() {
   info->set_prologue_offset(masm()->pc_offset());
   AssemblePrologue();
 
-  // Assemble all instructions.
-  for (InstructionSequence::const_iterator i = code()->begin();
-       i != code()->end(); ++i) {
-    AssembleInstruction(*i);
+  // Assemble all non-deferred instructions.
+  for (auto const block : code()->instruction_blocks()) {
+    if (block->IsDeferred()) continue;
+    for (int i = block->code_start(); i < block->code_end(); ++i) {
+      AssembleInstruction(code()->InstructionAt(i));
+    }
+  }
+
+  // Assemble all deferred instructions.
+  for (auto const block : code()->instruction_blocks()) {
+    if (!block->IsDeferred()) continue;
+    for (int i = block->code_start(); i < block->code_end(); ++i) {
+      AssembleInstruction(code()->InstructionAt(i));
+    }
   }
 
   FinishCode(masm());
@@ -83,6 +93,12 @@ Handle<Code> CodeGenerator::GenerateCode() {
 }
 
 
+bool CodeGenerator::IsNextInAssemblyOrder(BasicBlock::RpoNumber block) const {
+  return code()->InstructionBlockAt(current_block_)->ao_number().IsNext(
+      code()->InstructionBlockAt(block)->ao_number());
+}
+
+
 void CodeGenerator::RecordSafepoint(PointerMap* pointers, Safepoint::Kind kind,
                                     int arguments,
                                     Safepoint::DeoptMode deopt_mode) {