Visit the Optimized Code Map on first call rather than closure creation.

src/x64/builtins-x64.cc

Index: src/x64/builtins-x64.cc
diff --git a/src/x64/builtins-x64.cc b/src/x64/builtins-x64.cc
index dbd13289b7a525658aa545c16687714edab18dfe..38b4440863be77046f849022dccbcf667e3a3e3b 100644
--- a/src/x64/builtins-x64.cc
+++ b/src/x64/builtins-x64.cc
@@ -904,6 +904,134 @@ void Builtins::Generate_InterpreterEnterBytecodeDispatch(MacroAssembler* masm) {
 
 
 void Builtins::Generate_CompileLazy(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- rax : argument count (preserved for callee)
+  //  -- rdx : new target (preserved for callee)
+  //  -- rdi : target function (preserved for callee)
+  // -----------------------------------
+  // First lookup code, maybe we don't need to compile!
+  Label gotta_call_runtime;
+  Label maybe_call_runtime;
+  Label try_shared;
+  Label loop_top, loop_bottom;
+
+  Register closure = rdi;
+  Register map = r8;
+  Register index = r9;
+  __ movp(map, FieldOperand(closure, JSFunction::kSharedFunctionInfoOffset));
+  __ movp(map, FieldOperand(map, SharedFunctionInfo::kOptimizedCodeMapOffset));
+  __ SmiToInteger32(index, FieldOperand(map, FixedArray::kLengthOffset));
+  __ cmpl(index, Immediate(2));
+  __ j(less, &gotta_call_runtime);
+
+  // Find literals.
+  // r14 : native context
+  // r9  : length / index
+  // r8  : optimized code map
+  // rdx : new target
+  // rdi : closure
+  Register native_context = r14;
+  __ movp(native_context, NativeContextOperand());
+
+  __ bind(&loop_top);
+  // Native context match?
+  Register temp = r11;
+  __ movp(temp, FieldOperand(map, index, times_pointer_size,
+                             SharedFunctionInfo::kOffsetToPreviousContext));
+  __ movp(temp, FieldOperand(temp, WeakCell::kValueOffset));
+  __ cmpp(temp, native_context);
+  __ j(not_equal, &loop_bottom);
+  // OSR id set to none?
+  __ movp(temp, FieldOperand(map, index, times_pointer_size,
+                             SharedFunctionInfo::kOffsetToPreviousOsrAstId));
+  __ SmiToInteger32(temp, temp);
+  const int bailout_id = BailoutId::None().ToInt();
+  __ cmpl(temp, Immediate(bailout_id));
+  __ j(not_equal, &loop_bottom);
+  // Literals available?
+  __ movp(temp, FieldOperand(map, index, times_pointer_size,
+                             SharedFunctionInfo::kOffsetToPreviousLiterals));
+  __ movp(temp, FieldOperand(temp, WeakCell::kValueOffset));
+  __ JumpIfSmi(temp, &gotta_call_runtime);
+
+  // Save the literals in the closure.
+  __ movp(FieldOperand(closure, JSFunction::kLiteralsOffset), temp);
+  __ movp(r15, index);
+  __ RecordWriteField(closure, JSFunction::kLiteralsOffset, temp, r15,
+                      kDontSaveFPRegs, EMIT_REMEMBERED_SET, OMIT_SMI_CHECK);
+
+  // Code available?
+  Register entry = rcx;
+  __ movp(entry, FieldOperand(map, index, times_pointer_size,
+                              SharedFunctionInfo::kOffsetToPreviousCachedCode));
+  __ movp(entry, FieldOperand(entry, WeakCell::kValueOffset));
+  __ JumpIfSmi(entry, &maybe_call_runtime);
+
+  // Found literals and code. Get them into the closure and return.
+  __ leap(entry, FieldOperand(entry, Code::kHeaderSize));
+
+  Label install_optimized_code_and_tailcall;
+  __ bind(&install_optimized_code_and_tailcall);
+  __ movp(FieldOperand(closure, JSFunction::kCodeEntryOffset), entry);
+  __ RecordWriteCodeEntryField(closure, entry, r15);
+
+  // Link the closure into the optimized function list.
+  // rcx : code entry (entry)
+  // r14 : native context
+  // rdx : new target
+  // rdi : closure
+  __ movp(rbx,
+          ContextOperand(native_context, Context::OPTIMIZED_FUNCTIONS_LIST));
+  __ movp(FieldOperand(closure, JSFunction::kNextFunctionLinkOffset), rbx);
+  __ RecordWriteField(closure, JSFunction::kNextFunctionLinkOffset, rbx, r15,
+                      kDontSaveFPRegs, EMIT_REMEMBERED_SET, OMIT_SMI_CHECK);
+  const int function_list_offset =
+      Context::SlotOffset(Context::OPTIMIZED_FUNCTIONS_LIST);
+  __ movp(ContextOperand(native_context, Context::OPTIMIZED_FUNCTIONS_LIST),
+          closure);
+  // Save closure before the write barrier.
+  __ movp(rbx, closure);
+  __ RecordWriteContextSlot(native_context, function_list_offset, closure, r15,
+                            kDontSaveFPRegs);
+  __ movp(closure, rbx);
+  __ jmp(entry);
+
+  __ bind(&loop_bottom);
+  __ subl(index, Immediate(SharedFunctionInfo::kEntryLength));
+  __ cmpl(index, Immediate(1));
+  __ j(greater, &loop_top);
+
+  // We found neither literals nor code.
+  __ jmp(&gotta_call_runtime);
+
+  __ bind(&maybe_call_runtime);
+
+  // Last possibility. Check the context free optimized code map entry.
+  __ movp(entry, FieldOperand(map, FixedArray::kHeaderSize +
+                                       SharedFunctionInfo::kSharedCodeIndex));
+  __ movp(entry, FieldOperand(entry, WeakCell::kValueOffset));
+  __ JumpIfSmi(entry, &try_shared);
+
+  // Store code entry in the closure.
+  __ leap(entry, FieldOperand(entry, Code::kHeaderSize));
+  __ jmp(&install_optimized_code_and_tailcall);
+
+  __ bind(&try_shared);
+  // Is the full code valid?
+  __ movp(entry, FieldOperand(closure, JSFunction::kSharedFunctionInfoOffset));
+  __ movp(entry, FieldOperand(entry, SharedFunctionInfo::kCodeOffset));
+  __ movl(rbx, FieldOperand(entry, Code::kFlagsOffset));
+  __ andl(rbx, Immediate(Code::KindField::kMask));
+  __ shrl(rbx, Immediate(Code::KindField::kShift));
+  __ cmpl(rbx, Immediate(Code::BUILTIN));
+  __ j(equal, &gotta_call_runtime);
+  // Yes, install the full code.
+  __ leap(entry, FieldOperand(entry, Code::kHeaderSize));
+  __ movp(FieldOperand(closure, JSFunction::kCodeEntryOffset), entry);
+  __ RecordWriteCodeEntryField(closure, entry, r15);
+  __ jmp(entry);
+
+  __ bind(&gotta_call_runtime);
   GenerateTailCallToReturnedCode(masm, Runtime::kCompileLazy);
 }